DE102008037665A1 - variable displacement - Google Patents

Abstract

A variable displacement pump (1) comprises a drive is formed; Wings (32) received through the slots (31); a cam ring (4) which can become eccentric and cooperate with the rotor (3) and vanes (32) to define the pumping chambers; Suction ports (62, 121) and discharge ports (63, 122) opened to the pump chambers; a seal member (50) for dividing a space on an outer peripheral surface of the cam ring (4) into first and second fluid pressure chambers; a metering orifice (110, 24a, 111) formed on a discharge duct (22) connected to the discharge port (63, 122); and a pressure control section (7) that controls a pressure built up in the first or second fluid pressure chambers. The pressure control section (7) comprises a high-pressure chamber in which an upstream pressure of the metering orifice (110, 24a, 111) is established, a medium-pressure chamber in which a downstream pressure of the metering orifice (110, 24a, 111) is established, and a Low pressure chamber which is connected to a reservoir. The vane pump further includes a bleed valve (80) to discharge the downstream pressure of the metering orifice (110, 24a, 111) to the reservoir; and a variable metering mechanism (100) that at least limits a portion of the metering orifice (110, 24a, 111) when the drain valve (80) is opened.

Description

The The present invention relates to a variable displacement pump, in particular to a variable displacement pump for a power steering device.

The Japanese Published Patent Application No. 2003-21076 discloses an earlier developed variable displacement pump. In this technique, the vane pump includes a drain valve disposed within a control valve. This discharge valve serves to discharge a discharge side pressure into a reservoir when the discharge side pressure becomes higher than or equal to a predetermined pressure.

If however, in the above technique, an economy is attempted of fuel consumption by reducing a discharge amount of Working fluid from the drain valve by means of a constriction of a Pilot or control panel to improve, the drain valve is due vibrate a vibration of the working fluid itself, which is caused when the working fluid through the pilot aperture goes through. When using the drainage amount a damper aperture is reduced instead of the pilot aperture, To avoid this vibration, the working fluid escapes from an annular region of the control valve.

consequently a pressure difference of the valve is reduced, so that a control or control flow rate increased at high pressure state becomes. As a result, a pump load is increased, thus one Reversing effect to reduce fuel consumption by the reduction of the discharge amount of the working fluid is obtained. This problem has occurred.

It is therefore an object of the present invention, a variable displacement pump to reduce the amount of discharge and to suppress the Increase in pump load is designed to increase cost-effectiveness to improve fuel economy. The solution of this The object is achieved by the features of the independent claims 1, 12, 15 and 19, respectively. The subclaims have advantageous Further developments of the invention to the content.

According to one Aspect of the present invention is a variable displacement vane pump comprising: a pump body; a drive shaft rotatable by the pump body is supported; a rotor inside the pump body is arranged and rotatably driven by the drive shaft is where the rotor with a plurality of slots that are separated from each other are spaced in the circumferential direction of the rotor is formed; a plurality of wings; taken up by the slits are thus, away from the slots and into the slots to be mobile; a cam ring in an annular Form formed and arranged inside the pump body is to allow the cam ring with respect the drive shaft to be eccentric, wherein the cam ring with the rotor and the wings cooperate to a plurality of pump chambers on an inner peripheral side of the cam ring define; a first plate member and a second plate member, which are arranged on the two axial sides of the cam ring; a suction port on one side of at least either the first plate member or second plate member arranged and open at least to one of the plurality of pump chambers is; a discharge opening on one side of at least arranged either the first plate member or second plate member and open at least to one of the plurality of pump chambers is; a sealing element that is on an outer Circumference side of the cam ring is arranged, wherein the sealing element a space on an outer peripheral surface the cam ring in a first fluid pressure chamber and a second fluid pressure chamber divides, wherein a flow rate of the Working fluid coming from the discharge port is increased, when the cam ring for first fluid pressure chamber moves, with the flow rate the working fluid coming from the discharge opening is lowered, when the cam ring to the second Fluid pressure chamber moves; an orifice plate that open a discharge line is formed, which communicates with the discharge opening connected is; a pressure control area that controls pressure, in the first fluid pressure chamber or second Fluid pressure chamber is constructed, wherein the pressure control range a high pressure chamber in which an upstream one Pressure of the measuring diaphragm is built up, a middle pressure chamber, in which is a downstream pressure of the metering orifice is built, and a low-pressure chamber, which is connected to a reservoir for storing the working fluid is connected; a drain valve located between a downstream Side of the metering and the reservoir arranged is, wherein the drain valve opened by receiving a pressure that is greater than or equal to a predetermined one Level is, and thereby the downstream pressure the measuring orifice drains to the reservoir; and one variable measuring mechanism, which has a cross-sectional area the opening area of the orifice plate is at least limited, when the drain valve is open.

According to another aspect of the present invention there is provided a variable displacement vane pump comprising: a pump body; a drive shaft passing through the pump body is rotatably supported; a rotor disposed within the pump body and rotatably driven by the drive shaft, the rotor being formed with a plurality of slots spaced from each other in the circumferential direction of the rotor; a plurality of wings; which are received by the slots so as to be movable away from the slots and into the slots; a cam ring formed in an annular shape and disposed within the pump body to allow the cam ring to become eccentric with respect to the drive shaft, the cam ring cooperating with the rotor and the vanes to form a plurality of pump chambers on an inner peripheral side of the pump To define cam ring; a first plate member and a second plate member disposed on the two axial sides of the cam ring; a suction port disposed on one side of at least one of the first plate member and the second plate member and opened to at least one of the plurality of pump chambers; a discharge port disposed on one side of at least one of the first plate member and the second plate member and opened to at least one of the plurality of pump chambers; a seal member disposed on an outer peripheral side of the cam ring, the seal member dividing a space on an outer peripheral surface of the cam ring into a first fluid pressure chamber and a second fluid pressure chamber, thereby increasing a flow rate of the working fluid discharged from the discharge port; when the cam ring moves to the first fluid pressure chamber, wherein the flow rate of the working fluid discharged from the discharge port is reduced as the cam ring moves to the second fluid pressure chamber; a metering orifice formed on a discharge duct connected to the discharge port; a pressure control section that controls a pressure built up in the first fluid pressure chamber or the second fluid pressure chamber, the pressure control section constructs a high pressure chamber in which an upstream pressure of the metering orifice is established, a middle pressure chamber in which a downstream pressure of the metering orifice is established; and a low-pressure chamber connected to a reservoir for storing the working fluid; a drain valve disposed between a downstream side of the metering orifice and the reservoir, the drain valve being opened by receiving a pressure greater than or equal to a predetermined level, thereby draining the downstream pressure of the metering orifice to the reservoir; and a variable metering mechanism that limits a cross-sectional area of the opening area of the metering orifice when a discharge pressure on a downstream side of the discharge opening is greater than or equal to a predetermined pressure.

According to another aspect of the present invention there is provided a variable displacement vane pump comprising: a pump body; a drive shaft rotatably supported by the pump body; a rotor disposed within the pump body and rotatably driven by the drive shaft, the rotor being formed with a plurality of slots spaced from each other in the circumferential direction of the rotor; a plurality of wings; which are received by the slots so as to be movable away from the slots and into the slots; a cam ring formed in an annular shape and disposed within the pump body to allow the cam ring to become eccentric with respect to the drive shaft, the cam ring cooperating with the rotor and the vanes to form a plurality of pump chambers on an inner peripheral side of the pump To define cam ring; a first plate member and a second plate member disposed on the two axial sides of the cam ring; a suction port disposed on one side of at least one of the first plate member and the second plate member and opened to at least one of the plurality of pump chambers; a discharge port disposed on a side of at least one of the first plate member and the second plate member and opened to at least one of the plurality of pump chambers; a seal member disposed on an outer peripheral side of the cam ring, the seal member dividing a space on an outer peripheral surface of the cam ring into a first fluid pressure chamber and a second fluid pressure chamber, thereby increasing a flow rate of the working fluid discharged from the discharge port; when the cam ring moves to the first fluid pressure chamber, wherein the flow rate of the working fluid discharged from the discharge port is reduced as the cam ring moves to the second fluid pressure chamber; a metering orifice formed on a discharge duct connected to the discharge port; a pressure control section that controls a pressure built up in the first fluid pressure chamber or the second fluid pressure chamber, the pressure control section constructs a high pressure chamber in which an upstream pressure of the metering orifice is established, a middle pressure chamber in which a downstream pressure of the metering orifice is established; and a low-pressure chamber connected to a reservoir for storing the working fluid; a drain valve located between a downstream side of the meter and the reservoir is arranged, wherein the drain valve is opened by receiving a pressure which is greater than or equal to a predetermined level, and thereby derives the downstream pressure of the metering orifice to the reservoir; and a variable metering mechanism that limits a cross-sectional area of the orifice portion of the metering orifice to a greater extent when the eccentricity of the cam ring becomes smaller when the dumping valve is open.

According to one Another aspect of the present invention is a variable displacement vane pump comprising: a pump body; a drive shaft rotatable by the pump body is supported; a rotor inside the pump body is arranged and rotatably driven by the drive shaft is, wherein the rotor with a plurality of slots, of are spaced apart in the circumferential direction of the rotor formed is; a plurality of wings; through the slots are absorbed, thus away from the slots and into the slots to be mobile; a cam ring in an annular Mold is formed and disposed within the pump body, to allow the cam ring, with respect to the To be eccentric drive shaft, wherein the cam ring with the Rotor and the wings cooperates to a plurality of Pump chambers on an inner peripheral side of the cam ring to define; a first plate member and a second plate member, which are arranged on the two axial sides of the cam ring; a suction port on one side of at least either the first plate member or second plate member arranged and open at least to one of the plurality of pump chambers is; a discharge opening on one side of at least arranged either the first plate member or second plate member and open at least to one of the plurality of pump chambers is; a sealing element that is on an outer Circumference side of the cam ring is arranged, wherein the sealing element a space on an outer peripheral surface the cam ring in a first fluid pressure chamber and a second fluid pressure chamber divides, wherein a flow rate of the Working fluid coming from the discharge port is increased, when the cam ring for first fluid pressure chamber moves, with the flow rate the working fluid coming from the discharge opening is lowered, when the cam ring to the second Fluid pressure chamber moves; an orifice plate that open a discharge line is formed, which communicates with the discharge opening connected is; a pressure control area that controls pressure, in the first fluid pressure chamber or second Fluid pressure chamber is constructed, wherein the pressure control range a high pressure chamber in which an upstream one Pressure of the measuring diaphragm is built up, a middle pressure chamber, in which is a downstream pressure of the metering orifice is built, and a low-pressure chamber, which is connected to a reservoir connected to store the working fluid has; a fluid pressure sensor, one from the discharge port discharged pressure detected; a drain valve to the downstream Derive pressure of the orifice plate to the reservoir, and a pressure-using device to one of the discharge port to apply applied pressure; and a variable measuring mechanism, around a cross-sectional area of the flow line of the metering orifice the base of an output signal of the fluid pressure sensor to limit.

Further Details, advantages and features of the present invention result from the following description of exemplary embodiments the attached drawing. It shows:

1 a cross-sectional view of a vane pump in a first embodiment according to the present invention, which was taken in the axial direction of the vane pump.

2 a cross-sectional view of the vane pump in the first embodiment, which was taken in the radial direction of the vane pump (at a maximum swing position).

3 an enlarged cross-sectional view in the vicinity of a variable measuring mechanism.

4 a view illustrating the relationship between an opening area of the metering orifice and a swing amount of the cam ring.

5 a view illustrating an example in which a minimally protected area of the metering orifice is provided as a separate opening.

6 an enlarged view of 5 ,

7 a view illustrating an example in which the metering orifice is provided as a plurality of round openings.

8th a view illustrating an example in which a damping diaphragm is provided outside a first housing.

9 10 is a view illustrating an example in which a piston reciprocating in response to the vibration of the cam ring is formed with the metering orifice.

10 a cross-sectional view of a Flü Gelpumpe in a second embodiment according to the present invention, which was taken in the axial direction of the vane pump.

11 a cross-sectional view of the vane pump in the second embodiment, which was taken in the radial direction of the vane pump.

12 a view illustrating an example in which a coil is provided as an electromagnetic valve in the second embodiment.

13 a view illustrating an example in which a drain valve is provided outside of a housing in the second embodiment.

14 11 is a view illustrating an example in which a shape of the spool is changed so that the spool is operated by using a purge pressure generated on the downstream side of the purge valve in the second embodiment.

15 an enlarged view of 14 ,

It Reference is made to the drawing for a better understanding to enable the present invention. Verstellflügelpumpen according to the present invention will be hereinafter based on the embodiments of the present invention explained in the drawing.

First Embodiment

[Overview of the vane pump]

A first embodiment according to the present invention will now be explained. 1 is a cross-sectional view of a vane pump 1 in the first embodiment, in the axial direction of the vane pump 1 has been recorded. 2 is a cross-sectional view of the vane pump 1 in the radial direction of the vane pump 1 has been recorded. 2 represents the state in which a cam ring 4 was moved to its maximum negative position with respect to the y-axis (maximum eccentric amount). In 2 Oc denotes a center of the cam ring 4 , and O _R a center of a drive shaft 2 ,

The x-axis is considered the axial direction of the drive shaft 2 , and defines a positive direction of the x-axis as the direction in which the drive shaft 2 in the first and second housings 11 and 12 is used. In addition, the y-axis becomes an axial direction of a spring 91 (please refer 2 ) for regulating a vibration (oscillation) of the cam ring 4 Are defined. A negative direction of the y-axis is defined as the direction in which the spring 91 the cam ring 4 spans or tenses. The z-axis is defined as an axis that is orthogonal to the x and y axes, and a positive direction of the z-axis is defined as the direction to the inlet port IN.

The wing pump 1 includes the drive shaft 2 , Rotor 3 , Cam ring 4 , Adapter ring or fitting ring 5 and pump body 10 , The drive shaft 2 is connected by a pulley to a motor. The drive shaft 2 gets through the pump body 10 rotatably supported and rotates integrally with the rotor 3 ,

An outer peripheral portion of the rotor 3 is with a plurality of slots 31 designed as axial grooves. The majority of the slots 31 are in the rotor 3 radially fixed, and from each other in the circumferential direction of the rotor 3 spaced. A grand piano 32 is in every slot 31 used or is absorbed by him to the wing 32 to allow in the radial direction of the rotor 3 to rise or fall. That is, every wing 32 can be in the outer and inner direction of the slot 31 move. Every slot 31 is constantly with a back pressure chamber 33 connected to a radial inner end of the slot 31 is provided and which is acted upon by a fluid pressure. This fluid pressure tightens the wing 32 outward in the radial direction.

The pump body 10 includes a first housing 11 and a second housing 12 (corresponding to a first plate member according to the present invention). The first case 11 is like a bowl with a bottom 11a shaped and opened in the positive direction of the x-axis. A printing plate 6 (corresponds to a second plate member according to the present invention) in the form of a circular disc is on the bottom portion 11a of the first housing 11 arranged. That is, the first housing 11 takes the pressure plate 6 on the floor area 11a on. The first case 11 includes a pump element receiving area 11b on the inner peripheral portion of the first housing 11 , The pump element receiving area 11b takes the adapter ring 5 , Cam ring 4 and rotor 3 on which adjacent to the pressure plate 6 are arranged in the positive direction of the x-axis.

The second housing 12 lies on the adapter ring 5 , Cam ring 4 and rotor 3 liquid-tight from the positive side of the x-axis. The adapter ring 5 , Cam ring 4 and rotor 3 be through the pressure plate 6 and the second housing 12 supported, thus between the pressure plate 6 and the second housing 12 to be arranged in sandwich form.

A suction opening 62 and a tax office voltage 63 are in a plane 61 the positive x axis side of the printing plate 6 intended. Similar are a suction port 121 and a discharge opening 122 on a surface 120 the negative x-axis side of the second housing 12 intended. The intake openings 62 and 121 are connected to the inlet port IN. The discharge openings 63 and 122 are connected to an outlet port OUT. The suction and discharge openings 62 . 63 . 121 and 122 lead and give the working fluid to a pump chamber B to (from), between the rotor 3 and the cam ring 4 is trained. The inlet port IN is through a fluid line 7a with a control valve or control valve 7 connected.

The adapter ring 5 is a substantially elliptical annular member having a major axis along the y-axis and a minor axis along the z-axis. The outer peripheral side (ie, radial outside) of the adapter ring 5 is through the inner peripheral surface of the first housing 11 enclosed, and the inner peripheral side (ie radial inner side) of the adapter ring 5 encloses or takes the cam ring 4 on. The adapter ring 5 is through a pen 40 upon rotation with respect to the first housing 11 limited so that in fact within the first housing 11 at the time of drive operation of the vane pump 1 to turn.

The cam ring 4 is an annular member having a substantially complete roundness (ie, almost perfect circle). An outer diameter of the cam ring 4 is substantially equal to the minor axis of the elliptical bore of the adapter ring 5 , Because the cam ring 4 within the substantially elliptical adapter ring 5 is received, a fluid pressure chamber "A" between an inner peripheral surface 53 of the adapter ring 5 and an outer peripheral surface of the cam ring 4 educated. The cam ring 4 can be in the direction of the y-axis within the adapter ring 5 be swung.

As in 2 is shown, a sealing element 50 in a positive z-axis aligned end portion of the inner circumferential surface 53 of the adapter ring 5 intended. On the other hand, the adapter ring 5 supported by a support surface N on an end portion oriented in the negative z-axis. In particular, the sealing element 50 in the most advanced position of the inner circumferential surface 53 of the adapter ring 5 in the positive direction of the z-axis, and the support surface N in the most advanced position of the inner circumferential surface 53 of the adapter ring 5 arranged in the negative direction of the z-axis. The cam ring 4 is swingable via a swing fulcrum, which is set on the support surface N. The cam ring 4 is in contact with the support surface N and becomes on the support surface N of the adapter ring 5 supported vibratable in the negative direction of the z-axis.

A pen 40 (A second sealing element) is provided in the support surface N. The pencil 40 and the sealing element 50 interact with each other to move the fluid pressure chamber "A" through the cam ring 4 and the adapter ring 5 is defined to be divided into a first fluid pressure chamber A1 and a second fluid pressure chamber A2. That is, because the first fluid pressure chamber A1 of the second fluid pressure chamber A2 by means of the pin 40 and sealing element 50 is separated, the first fluid pressure chamber A1 on the negative side of the y-axis and the second fluid pressure chamber A2 on the positive side of the y-axis is formed.

Because the cam ring 4 by swinging on the support surface N swings, the volume capacities of the respective fluid pressure chambers A1 and A2 are changed. As in 2 is shown, the support surface N with the ξ-axis parallel, which by rotating the y-axis around an origin point of the coordinate system in the clockwise direction of 2 is defined. That is, the support surface N is inclined in the positive direction of the z-axis, and thereby a positive side of the y-axis of the support surface N at a higher positive position of the z-axis than a negative side of the y-axis Support surface N arranged. Consequently, the noise ring tends 4 to swing in the negative direction of the y-axis because of the inclined support surface N.

An outer diameter of the rotor 3 is smaller than a diameter of an inner circumference (area) 41 of the cam ring 4 , The rotor 3 is within a central bore of the cam ring 4 arranged. The rotor 3 is arranged so as to prevent the outer circumference of the rotor 3 on the inner circumference 41 of the cam ring 4 abuts, even if the oscillating movement of the cam ring 4 a relative position between the rotor 3 and cam ring 4 changed.

When the cam ring 4 to its swinging position in the farthest negative direction of the y-axis, a distance L (radial distance of a pumping chamber By-) between the inner periphery becomes 41 of the cam ring 4 and the outer circumference of the rotor 3 on the negative side of the y-axis maximum. On the other hand, when the cam ring 4 to its swinging position in the farthest positive direction of the y-axis, the distance L on the positive side of the y-axis becomes maximum.

Every wing 32 has a radial length greater than a maximum value of the distance L (radial distance). Therefore, each wing remains 32 in the state where a radial inner portion of the wing 32 in the corresponding slot 31 turned sets or was recorded and a radial outer area of the wing 32 is with the inner circumference 41 of the cam ring 4 regardless of the relative position between the rotor 3 and cam ring 4 , As a result, the back pressure will always be from each back pressure chamber 33 on the respective wing 32 applied, leaving the wing 32 in fluid-tight contact with the inner periphery 41 of the cam ring 4 is.

This creates a space between the rotor 3 and cam ring 4 into the pump chambers B through the wings 32 divided adjacent to each other in the circumferential direction of the cam ring 4 and rotors 3 are arranged. Each through the adjacent wings 32 trained pump chamber B is always maintained liquid-tight. That is, the cam ring 4 acts with the rotor 3 and wings 32 together to the pump chambers B on the inner peripheral side of the cam ring 4 A volume of each pump chamber B changes according to the rotation of the rotor 3 in the case where the cam ring 4 and rotor 3 in eccentric relation to each other as a result of the vibration of the cam ring 4 are positioned.

The intake openings 62 and 121 and discharge openings 63 and 122 , each in the printing plate 6 and the second housing 12 As mentioned above, are along the outer circumference of the rotor 3 educated. The intake openings 62 and 121 are open to a region (some chambers) of the plurality of pump chambers B, in which the volume of the pump chamber B with the rotation of the rotor 3 increases, as in 2 shown. In addition, the discharge openings 63 and 122 open to a region (some chambers) of the plurality of pump chambers B, in which the volume of the pump chamber with the rotation of the rotor 3 decreases. The supply and discharge of working fluid through these openings 62 . 63 . 121 and 122 performed by changing the volume of each pump chamber B.

The adapter ring 5 has a radial through hole 51 at an end portion thereof in the positive direction of the y-axis. In addition, the first housing has 11 a closure element insertion opening 114 at an end portion thereof in the positive direction of the y-axis. A closure element 90 , which is formed like a shell with bottom, is in the closure element insertion opening 114 used, and serves the first and second housings 11 and 12 maintain liquid-tight against the exterior thereof.

A feather 91 becomes radially inside an inner periphery of the shutter member 90 (ie in an inner bore of the closure element 90 ) and is stretchable and compressible in the y-axis direction. The feather 91 extends through the radial through hole 51 of the adapter ring 5 and lies on the cam ring 4 at. This tenses the spring 91 the cam ring 4 in the negative direction of the y-axis.

The feather 91 tenses the cam ring 4 in the negative direction of the y-axis, namely in the direction in front, the amount of swinging motion of the cam ring 4 causes it to become maximum (maximum eccentricity). This biasing force of the spring 91 serves to stabilize the oscillating position of the cam ring 4 at the time of starting the vane pump 1 during which the fluid pressure becomes unstable. That is, the spring 91 serves to stabilize the flow rate of the working fluid at the time of start-up of the vane pump 1 is to be delivered.

[Control valve]

The control valve 7 (corresponding to a pressure control range according to the present invention) is a mechanical valve operated based on the discharge and suction pressures. The first case 11 is with a valve receiving opening 115 formed in a positive region of the z-axis of the first housing 11 is arranged. The control valve 7 is in the valve receiving opening 115 recorded or arranged. This control valve 7 includes a coil 71 and a spring 72 , In the radial inside of the coil 71 , which is formed in a tubular shape with bottom, is a drain valve 80 arranged.

(Kitchen sink)

The sink 71 is a hollow cylindrical (tubular) member having a closed end, namely its bottom portion 71a , The floor area 71a is at one end of the coil 71 arranged in the negative direction of the y-axis. At another end of the coil 71 in the positive direction of the y-axis, namely in the open area 71b the coil 71 , tenses the spring 72 the sink 71 in the negative direction of the y-axis. In addition, an outer circumference of the coil includes 71 a sealing area 71c fluid-tight with an inner circumferential surface of the valve receiving opening 115 is in contact.

The opening area 71b is also in fluid-tight contact with the inner peripheral surface of the valve receiving opening 115 , Therefore, the coil shares 71 the valve receiving opening 115 in three chambers, namely a high pressure chamber CH, medium pressure chamber C _M and low pressure chamber C _L , which are all sealed from each other. The high-pressure chamber C _H becomes on the negative side of the y-axis of the coil 71 educated. The medium pressure chamber C _M is on the positive side of the y-axis of the coil 71 educated. The low-pressure chamber C _L becomes on the outer circumferential surface of the coil 71 and between the sealing area 71c and opening area 71b formed (that is, the outer peripheral portion of the coil 71 is from the sealing area 71c , Opening area 71b and first housing 11 enclosed).

The valve receiving opening 115 is through a fluid line 113 and a through hole 52 connected to the first fluid pressure chamber A1. The first case 11 is with this fluid line 113 educated. The through hole 52 is a radial through hole in the adapter ring 5 is provided. The sealing area 71c the coil 71 is located at the position that the fluid line 113 closes when the spring 72 not compressed.

When the coil 71 moves in the positive direction of the y-axis, therefore, the liquid line 113 connected to the high pressure chamber C _H , so that a high pressure in the first fluid pressure chamber A1 is established. On the other hand, when the coil 71 moving in the negative direction of the y-axis, the liquid line 113 connected to the low pressure chamber C _L , so that a low pressure in the first fluid pressure chamber A1 is established.

A negative area of the y axis of the high pressure chamber C _H is through a pilot aperture 300 and a liquid line 21 with the discharge openings 63 and 122 connected. The low-pressure chamber C _L is through the liquid line 7a connected to the inlet port IN. This fluid line 7a is at a higher positive position than the sealing area 71c provided with respect to the y-axis, and therefore not connected to the high-pressure chamber C _H.

The medium-pressure chamber C _M is through a fluid line 116 and a damping shutter 200. connected to the second fluid pressure chamber A2. In addition, the second fluid pressure chamber A2 through a metering orifice 110 with a delivery line 22 and the discharge openings 63 and 122 connected. The measuring aperture 110 is in the printing plate 6 intended. Consequently, the liquid pressures of the high-pressure chamber C _H and the medium-pressure chamber C _M correspond to an upstream (liquid) pressure and a downstream pressure of the metering orifice, respectively 110 , A pressure difference between the upstream pressure and the downstream pressure is a flow rate (flow rate) of the metering orifice 110 proportional.

[Vibration of the cam ring]

A fluid control pressure of the control valve 7 is through the fluid line 113 and through hole 52 constructed in the first fluid pressure chamber A1. In addition, the downstream pressure of the metering orifice becomes 110 constructed in the second fluid pressure chamber A2.

According to an increase in the discharge pressure, the liquid pressure difference becomes the metering orifice 110 greater, so that the pressure difference between the high-pressure chamber C _H , with the upstream side of the metering orifice 110 is connected, and the medium-pressure chamber C _M , with the downstream side of the orifice plate 110 is connected, also gets bigger. This pressure difference moves the coil 71 of the control valve 7 in the positive direction of the y-axis against the biasing force of the spring 72 , Thereby, the first fluid pressure chamber A1 is connected to the high pressure chamber C _H , so that a high pressure Ph is established in the first fluid pressure chamber A1.

In the meantime, the downstream pressure of the orifice becomes 110 in the second fluid pressure chamber A2, which is connected to the medium-pressure chamber C _M constructed. Thereby, the pressure difference between the first and second fluid pressure chambers A1 and A2 is effected (becomes larger). This pressure difference oscillates the cam ring 4 in the positive direction of the y-axis against the biasing force of the spring 91 ,

Consequently, the pump chamber By-, which is located on the negative side of the y-axis, reduced in size, so that an amount of the working fluid, which in the discharge openings 63 and 122 is pushed (pressed), is reduced. Meanwhile, a pump chamber By + disposed on the positive side of the y-axis is increased, so that an amount of the working liquid that flows to the suction ports 62 and 121 is pushed back (returned) is increased. Thus, a pump discharge amount (discharge amount) is reduced, and thereby the pressure difference of the metering orifice 110 reduces, so as to reduce the pressure difference between the high pressure chamber C _H and medium pressure chamber C _N.

Consequently, the coil is 71 unable, the biasing force of the spring 72 stand, and thereby moves in the negative direction of the y-axis. Then, the communication between the first fluid pressure chamber A1 and the high-pressure chamber C _{H is} shut off, so that the fluid pressure of the first fluid pressure chamber A1 is reduced. Consequently, the pressure difference between the first fluid pressure chamber A1 and the second fluid pressure chamber A2 is reduced, and that in the positive y-axis aligned force caused by this pressure difference becomes with the biasing force of the spring 91 balanced (or equalized). This will cause the oscillation of the cam ring 4 stopped.

As explained above, the pressure difference represents the metering orifice 110 and the biasing forces of the springs 72 and 91 the position of the cam ring 4 so as to always maintain a constant discharge rate (discharge amount). In the event that an opening area of the metering orifice 110 is small, the pressure difference becomes large. In the case that the opening area of the metering orifice 110 is large, the pressure difference becomes small.

(Discharge valve)

The drain valve 80 includes a valve body 81 , Valve seat 82 , Valve ball 83 and spring 84 , One end of the spring 84 is with the floor area 71a the coil 71 firmly connected. The feather 84 clamps the valve body 81 in the positive direction of the y-axis. This is the valve body 81 with the valve ball 83 in contact, and cocking the valve seat 82 in the positive direction of the y-axis through this valve ball 83 in front.

An outer peripheral surface of the positive y-axis-aligned end portion 81a of the valve body 81 is liquid-tight with an inner circumferential surface of the coil 71 in contact. Therefore, the valve body acts 81 with the inner circumference of the coil 71 together to define a first liquid chamber D1. The sink 71 is with a first radial bore 71d coming from the outer circumference of the coil 71 is provided, trained. The first radial hole 71d connects the inner circumferential surface of the coil 71 with the outer peripheral surface of the coil 71 to an interior of the coil 71 with an outside space of the coil 71 connect to.

When the spring 84 the drain valve 80 in the widest expanded state (ie, when the spring 84 extended to its greatest extent), becomes the first radial bore 71d at a higher negative position with respect to the y-axis than the end region 81a of the valve body 81 arranged. At this time, the first radial bore connects 71d the low pressure chamber C _L with the first liquid chamber D1. When the valve body 81 moved in the negative direction of the y-axis, the first radial bore 71d closed.

The valve seat 82 includes a through hole 82a formed in the y-axis direction. On a negative side of the y-axis of this through hole 82a becomes the through hole 82a through the valve ball 83 between the through hole 82a and valve body 81 is provided, closed or locked. A positive area of the y-axis of the valve seat 82 is the medium pressure chamber C _M opposite. The outer circumference of the valve seat 82 is on the inner circumference of the coil 71 fixed by means of interference fit, and thereby a second liquid chamber D2 between the valve body 81 and valve seat 82 educated.

Because the through hole 82a in the valve seat 82 is provided in the y-axis direction, a mean pressure Pm through the through hole 82a at the valve ball 83 applied in the negative direction of the y-axis. When the mean pressure Pm within the medium-pressure chamber C _M increases, the valve ball becomes 83 in the negative direction of the y-axis against the biasing force of the spring 84 pressed. This will cause the valve ball 83 from the through hole 82a dissolved (removed), so that the medium-pressure chamber C _{M is} connected to the low-pressure chamber C _L. Thus, a discharge state is achieved in which the medium pressure Pm through the liquid line 7a is derived to the inlet port IN.

(Vibration of the cam ring at the time of draining)

Because the liquid line 116 and damping aperture 200. are provided upstream of the medium-pressure chamber C _M , the fluid pressure of the medium-pressure chamber C _{M is} reduced at the time of the Ablasszustandes. As a result, the pressure difference between the medium-pressure chamber C _M and high-pressure chamber C _H becomes larger, so that the coil 71 in the positive direction of the y-axis by holding against the biasing force of the spring 72 emotional.

Thereafter, the first fluid pressure chamber A1 is connected to the high-pressure chamber C _H. Because of the high pressure, the cam ring 4 swung in the positive direction of the y-axis, so that the discharge flow rate is reduced. Because of the reduction in the discharge flow rate, the pressure difference becomes the metering orifice 110 reduces, so that the pressure difference between the medium pressure chamber C _M and high pressure chamber C _{H is} reduced. Thereby, the pressure Ph of the high-pressure chamber C _H is unable, the biasing force of the spring 72 withstand, so that the coil 71 moved in the negative direction of the y-axis.

Thereby, the connection between the high-pressure chamber C _H and the first fluid pressure chamber A1 is blocked and the pressure of the first fluid pressure chamber A1 is reduced. Here, the force directed in the positive y-axis, which is from the first fluid pressure chamber A1 on the cam ring 4 is applied, reduced, so that the vibration of the cam ring 4 stops. Thus, the discharge amount is reduced.

As a result, the pressure difference between the upstream and downstream sides of the metering orifice 110 reduced. That is, the increase in this pressure difference between the upstream and downstream sides is corrected, so that the pump discharge amount is maintained at a predetermined flow rate. At the discharge state, therefore, an excess flow quantity (quantity) by the vibration of the cam ring becomes 4 reduced, so as to improve the effect.

(Metering)

3 Fig. 10 is an enlarged cross-sectional view near a variable measuring (throttling) mechanism 100 , The measuring aperture 110 is a long (and narrow) bore that runs along the circumferential direction of the vane pump 1 is trained. An opening area of the metering orifice 110 is due to the y-axis aligned vibration of the cam ring 4 changed.

That the metering orifice 110 defining slot is created to cause a main (longer) axis of the metering orifice 110 deviates slightly from the z-axis direction. That is, the main axis of the orifice plate 110 is from a tangent of the cam ring 4 inclined, which is perpendicular to an imaginary line passing through a center of the main axis of the orifice plate 110 and center Oc of the cam ring 4 passes. An area 111 of the end zone of the measuring orifice in the negative z-axis 110 is not closed by the cam ring, even if the cam ring 4 in the positive direction the y-axis swings to its greatest extent, as in 3 shown. Therefore, the orifice plate is 110 always to the second fluid pressure chamber A2 at least through the minimum protected area 111 open. That is, the minimum protected area 111 that does not go through the cam ring 4 is always connected to the second fluid pressure chamber A2 in combination.

When the cam ring 4 Swings in the positive direction of the y-axis, the opening area of the orifice becomes 110 partly through the cam ring 4 closed around the opening area of the metering orifice 110 to reduce. When the cam ring 4 reaches its position farthest in the positive direction of the y-axis, the orifice becomes 110 closed, except for a single area (minimum protected area 111 ). This variable measuring mechanism 100 , which changes the area of the flow line, is through the metering orifice 110 and cam ring 4 reached.

Because the opening area of the metering orifice 110 in the form of a long narrow bore (elliptical slot) in the circumferential direction of the cam ring 4 is extended, is provided, the metering orifice 110 gradually closed after the cam ring is swung through a predetermined angle. Therefore, the orifice plate becomes 110 not at the time of a non-discharge state where the discharge amount is constant, closed or limited. Thereby, it is suppressed that the control of the discharge amount by the change of the pressure difference between the upstream and downstream sides of the metering orifice 110 being affected. This facilitates performing tuning of the discharge amount control.

Because also the opening area in the metering orifice 110 like an elongated hole having the larger circumferential width than the radial width thereof as mentioned above, the opening area of the metering orifice may be formed 110 short term according to a degree (displacement) of the vibration of the cam ring 4 be reduced.

[Flüssigkeitsdruckbeaufschlagung the first and second fluid pressure chambers]

The discharge pressure is through the on the liquid line 21 provided pilot panel 300 limited, and then applied to the high pressure chamber C _H , thus the coil 71 to bias in the positive direction of the y-axis. This will move the coil 71 in the positive direction of the y-axis, so that the high-pressure chamber CH with the liquid line 113 connected is. Consequently, the pressure PH of the high-pressure chamber C _{H is established} in the first fluid pressure chamber A1. The discharge pressure is also on the discharge line 22 applied, and thereafter in the second fluid pressure chamber A2 by the restriction by the orifice 110 constructed as in 2 shown.

Because the fluid pressure of the second fluid pressure chamber A2 is applied to a fluid pressure receiving passage (which is connected to a pressure applying device) outside the vane pump 1 is arranged, the diaphragm pressure difference occurs in proportion to the flow rate of the metering orifice 110 on. As a result, the mean pressure Pm of the medium-pressure chamber C _M , downstream of the metering orifice 110 is arranged smaller than the pressure Ph of the high-pressure chamber C _H , upstream of the metering orifice 110 is arranged. Consequently, the second fluid pressure chamber A2 has a lower pressure than that of the first fluid pressure chamber A1, so that the cam ring 4 vibrates in the positive direction of the y-axis.

When the cam ring 4 oscillates; decreases the pump discharge quantity and the pressure difference of the flow rate from the metering orifice 110 is reduced. This will change the pressure difference between the high-pressure chamber C _H and the medium-pressure chamber C _{M is} reduced, so that the biasing force of the spring 72 the sink 71 moved in y-axis direction. Thereby, the pressure applied to the first fluid pressure chamber A1 is reduced, so that the vibration of the cam ring 4 is stopped. Thus, the predetermined discharge amount is achieved.

The outer peripheral side of the cam ring 4 takes the pressures of the first and second fluid pressure chambers A1 and A2, and the inner peripheral side of the cam ring 4 the discharge pressure in the negative direction of the y-axis and also in the negative direction of the z-axis. The vibration of the cam ring 4 is stopped at a position that nullifies a balance between these pressures.

In the case that the discharge amount due to the reduction of the pressure difference of the metering orifice 110 becomes smaller, the pressure Ph within the high-pressure chamber C _{H is also} reduced. This will make the coil 71 in the negative direction of the y-axis by the biasing force of the spring 72 moves, so that the low-pressure chamber C _L with the liquid line 113 is connected. Thereby, a low pressure PI is established in the first fluid pressure chamber A1, so that the fluid pressure becomes lower in the first fluid pressure chamber A1 than in the second fluid pressure chamber A2. Consequently, the cam ring returns 4 back in the negative direction of the y-axis. Thus, the pressure difference of the metering orifice becomes 110 constant to reach or maintain the predetermined flow rate.

[Reduction of the delivery amount during the discharge condition]

4 is a view showing a relationship between the opening area of the metering orifice 110 and the amount of vibration of the cam ring 4 (the position of the cam ring by its swinging motion) represents. In the case where the amount of vibration of the cam ring 4 is within a normal scope; becomes the metering orifice 110 not through the cam ring 4 closed, and that remains the opening area of the metering orifice 110 constant throughout the open state. Consequently, the discharge amount becomes a constant flow rate by the movement of the spool 71 , Vibration of the cam ring 4 and pressure difference of the metering orifice 110 maintained.

In the case of the Ablasszustandes, where the pressure of the medium-pressure chamber C _M through the drain valve 80 and the fluid line 7a is derived to the inlet port IN, the pressure of the medium-pressure chamber C _M due to the existence of the liquid line 7a and pilot aperture 300 reduced.

Thereby, the pressure Ph of the high pressure chamber C _H becomes larger than the pressure Pm of the medium pressure chamber C _M , so that the pressure P1 of the first fluid pressure chamber A1 connected to the high pressure chamber C _H becomes larger than the pressure P2 of the second fluid pressure chamber A2 is connected to the medium pressure chamber CM. Consequently, the cam ring vibrates 4 in the positive direction of the y-axis, so that the discharge amount is reduced. In this discharge state, here, the swing amount (ie, the displacement in the positive direction of the y-axis) of the cam ring becomes 4 further increased, as mentioned above.

Because the cam ring 4 moves in the positive direction of the y-axis, the opening area of the orifice becomes 110 reduced. Because the opening area of the metering orifice 110 is reduced, the pressure difference between both sides of the metering orifice 110 elevated. Consequently, the pressure difference between the high-pressure chamber C _H and the medium-pressure chamber C _{M is also} increased. Therefore, the coil moves 71 in the positive direction of the y-axis, so that the high pressure chamber C _{H is} connected to the first fluid pressure chamber A1. Because the pressure P1 of the first fluid pressure chamber A1 increases, the cam ring vibrates 4 further in the positive direction of the y-axis, so that the discharge amount is further reduced.

As explained above, at the time of the discharge state, the excess amount of the working liquid discharged from the medium-pressure chamber C _M to the inlet port IN is reduced by restricting the flow rate to the medium-pressure chamber C _M. Thus, the discharge amount of the working fluid during the discharge state is reduced, thus improving the economy of fuel consumption.

In this embodiment, the vibration of the cam ring changes 4 the cross-sectional area of the flow line (the opening area of the orifice plate 110 ), and thereby the discharge amount of the working fluid is reduced. Thereby, the discharge amount of the working fluid is linked with the change in the cross-sectional area of the flow passage using the simple arrangement.

By providing the pilot aperture 300 will also move in the positive direction of the y-axis of the cam ring 4 facilitates, so that narrowing or reducing the opening area of the metering orifice 110 is simplified. Thereby, the discharge amount of the working fluid at the time of the discharge is further reduced. Here, the discharge state can be judged accurately or by detecting the movement (position) of the cam ring oriented in the positive y-axis 4 be recognized.

In the event that the pilot aperture 300 is further limited, it is foreseeable that the pressure Pm of the medium-pressure chamber C _{M will be} even easier to reduce at the time of Ablasszustandes, and thereby the oscillation amount of the cam ring 4 makes it bigger to further reduce excess flow. However, in this case it is to be feared that a vibration of the valve ball 83 at the discharge state, the pressure Pm of the medium-pressure chamber C _M can fluctuate, so that the coil 71 and the cam ring 4 vibrates. This is to be feared that a vibration of the discharge pressure is effected.

Thereby, in this embodiment according to the present invention, the arrangement using the metering orifice is used 110 reduced at the time of Ablasszustandes. According to this arrangement, the narrowing (narrowing) of the pilot aperture 300 be set relatively moderate. In this embodiment, the excess flow rate is reduced without causing the vibration of the liquid pressure.

By providing the attenuation panel 200. will also cause a vibration of the coil 71 , which is caused due to the discharge pressure, and also suppresses the liquid pressure vibration at the time of the discharge state, so that the control valve 7 is constantly in operation, resulting in a stable oscillation of the cam ring 4 leads.

[Arrangements and effects according to the first embodiment]

• (1) The variable displacement pump in the first embodiment includes the metering orifice 110 on the delivery line 22 that with the discharge openings 63 and 122 is connected, is formed; the control valve 7 controlling the pressure established in the first fluid pressure chamber A1 or the second fluid pressure chamber A2, wherein the control valve 7 the high-pressure chamber C _H , in which the upstream pressure of the metering orifice 110 is constructed, the medium pressure chamber C _M , in which the downstream pressure of the metering orifice 110 is constructed, and the low-pressure chamber C _L , which is connected to the reservoir RSV for storing the working fluid comprises; the drain valve 80 located between the downstream side of the orifice plate 110 and the reservoir RSV is provided, wherein the drain valve 80 by opening a pressure greater than or equal to a predetermined level and thereby the downstream pressure of the metering orifice 110 to the reservoir RSV derived; and the variable measuring mechanism 100 , which is the cross-sectional area of the opening area (flow line) of the metering orifice 110 at least limited if the drain valve 80 is open. Consequently, it is possible that the flow through the orifice plate 110 is reduced at the time of draining, leaving the cam ring 4 is swung. Thereby, the excess amount of liquid, which is derived from the medium-pressure chamber C _M to the inlet port IN, reduced. Thus, the excess flow rate can be steadily reduced without generating the fluid pressure vibration. Thereby, the increase in the pump load can be suppressed while the discharge amount is reduced, thereby improving the fuel economy.
• (2) The cam ring 4 vibrates to gradually increase the opening area of the metering orifice 110 and therefore becomes the variable measuring mechanism 100 through the measuring aperture 110 and the cam ring 4 receive. Further, the opening area of the metering orifice becomes 110 in the axial end surface of the first plate member 12 or second plate element 6 educated. Consequently, the reduction of the discharge flow rate of the working fluid with the change of the cross-sectional area of the flow passage at the discharge state can be linked with the application of the simple arrangement.
• (3) The variable measuring mechanism 100 limited gradually the opening area of the metering orifice 110 after the cam ring 4 is swinging to its position at a predetermined angle. Consequently, the orifice plate becomes 110 at the time of the non-discharge state in which the discharge amount is constant, locked or limited. This suppresses the control of the discharge amount by changing the pressure difference between the upstream and downstream sides of the metering orifice 110 being affected. Thereby, the execution of tuning the control of the discharge amount can be facilitated.
• (4) The circumferential width of the opening area of the metering orifice 110 is greater than the radial width thereof. Consequently, the range of the orifice plate 110 for the amount of vibration of the cam ring 4 be clearly limited, thus greatly reducing the excess flow rate.
• (5) The opening area of the metering orifice 110 is formed in an elliptical shape or slot shape. Consequently, the area of the measuring probe 110 be significantly limited for the vibration amount of the cam ring, thus greatly reducing the excess flow rate.
• (6) The variable displacement pump further includes a pilot diaphragm 300 which is provided on the line which the discharge openings 63 and 122 connects to the high pressure chamber C _H. Consequently, the discharge state based on the Schwingbe movement of the cam ring 4 be set exactly.
• (7) The variable displacement pump further includes the damping orifice 200. , which is provided on the line, which the metering orifice 110 connects to the medium pressure chamber CM. Consequently, the stability of the control valve 7 be improved at the time of discharge.

Further modified examples according to the first embodiment are explained below.

[First Modified Example According to the first embodiment]

5 and 6 An example is where the minimum protected area 111 the measuring aperture 110 is provided as a separate hole (another hole). Although the main axis of the metering orifice 110 (ie, the longer axis of the cross-section of the orifice plate 110 ) is tilted from the z-axis in the above-mentioned example of the first embodiment, the metering orifice becomes 110 formed in the first modified example of the first embodiment as a slot (slot) with the main axis parallel to the z-axis. In the first modified example, the hole (another hole) is used separately on the positive side of the y-axis of the metering orifice 110 is formed as a minimum protected area 111 ,

The measuring aperture 110 is completely closed when the cam ring 4 reaches its highest positive oscillatory position with respect to the y-axis, and is completely closed at the position indicated by a dashed line alternately with a long and two short dashes 6 is shown. On the other hand, the minimum protected area becomes 111 disposed at a position regardless of the swinging position of the cam ring 4 not closed. This will make the main (longer) axis of the metering orifice 110 provided parallel to the z-axis, so that a manufacturing process of the metering orifice 110 can be simplified.

[Second Modified Example According to the first embodiment]

7 represents an example in which the orifice plate 110 is provided as a plurality of bores, each having a substantially complete roundness. As a result, a sufficient opening area as well as a shape rigidity near the opening area of the metering orifice can be provided 110 be guaranteed.

[Third Modified Example According to the first embodiment]

8th FIG. 4 illustrates an example that further modifies the first modified example discussed above such that the attenuation aperture 200. outside the adapter ring 5 is provided. In the third modified example becomes a liquid line 23 connecting the second fluid pressure chamber A2 to the medium pressure chamber C _M , outside the first housing 11 provided, and this fluid line 23 with the attenuation panel 200. educated.

[Fourth Modified Example According to the first embodiment]

9 represents an example in which a piston 92 that is in response to the vibration of the cam ring 4 moved back and forth, is provided, and this piston 92 with the measuring aperture 110 is trained. The piston 92 is on the negative side of the y-axis of the closure element 90 and on the positive side of the y-axis of the cam ring 4 arranged. The piston 92 is a circular tubular (hollow cylindrical) element with bottom. The bottom area of the piston 92 lies on the cam ring 4 in the negative direction of the y-axis.

An outer circumferential surface of the piston 92 is in the closure element insertion opening 114 slidable and liquid-tight used. As a result, the piston acts 92 with the closure element 90 together to define a third fluid chamber D3. An inner circumference of the closure element 90 comes with an opening area 22a the delivery line 22 that with the discharge openings 63 and 122 is connected, trained. Thereby, the discharge pressure is built up in the third liquid chamber D3 and acts with the spring 91 together to the piston 92 to bias in the negative direction of the y-axis. Consequently, the cam ring 4 in the negative direction of the y-axis through the piston 92 by means of the biasing force of the spring 91 and the pressure of the third fluid pressure chamber D3 biased.

A tubular portion of the piston 92 is formed with small (through) bores, each of them forming an inner circumferential surface of the piston 92 with an outer circumferential surface of the piston 92 combines. These small holes are called orifice plate 110 used. The piston 92 is through the cam ring 4 in the positive direction of the y-axis according to the positive y-axis aligned vibration of the cam ring 4 and thereby moves in the positive direction of the y-axis against the pressures of the spring 91 and third fluid chamber D3.

• (8) Die Verstellflügelpumpe gemäß der ersten Ausführungsform umfasst ferner den Kolben 92, der sich als Antwort auf die Schwingung des Nockenrings 4 bewegt; und die Messblende 110 wird im Kolben 92 ausgebildet. Folglich wird die Undichtigkeit der Messblende 110 relativ klein, so dass die Genauigkeit bei der Steuerung der Mengenmessung (Reduzierung) verbessert werden kann.

When the piston 92 moves in the positive direction of the y-axis, the piston 92 firmly in the closure element insertion opening 114 used (recessed). This will make the metering orifice 110 through (the inner surface of) the shutter insertion hole 114 closed. Thus, the variable measuring mechanism becomes 100 created in the fourth modified example. Consequently, the discharge amount of the working liquid at the time of the discharge state is reduced in a similar manner to the non-modified example of the first embodiment. Because in this fourth modified example the orifice plate 110 through the closure element insertion opening 114 is closed, a leak in the metering orifice 110 relatively low, so that an accuracy in the control of the quantity measurement (reduction) is improved.

• (8) The variable displacement pump according to the first embodiment further includes the piston 92 that is in response to the vibration of the cam ring 4 emotional; and the measuring aperture 110 is in the piston 92 educated. Consequently, the leakage of the metering aperture becomes 110 relatively small, so that the accuracy in the control of the quantity measurement (reduction) can be improved.

Second Embodiment

A second embodiment according to the present invention will now be explained. A base assembly of the second embodiment is similar to the first embodiment. Although the on the delivery line 22 intended opening area as a measuring aperture 110 is used in the first embodiment, corresponds to a region of the flow line changing coil 400 the measuring aperture 110 in the second embodiment as a different point from the first embodiment.

10 is a cross-sectional view of a vane pump 1 according to the second embodiment, in the axial direction of the vane pump 1 has been recorded. 11 is a cross-sectional view of the vane pump 1 in the axial direction of the vane pump 1 has been recorded. Because the cross section of 11 from the cross section ( 2 ) received in the axial direction in the first embodiment is different, becomes only a part of the control valve 7 in 11 shown. The first case 11 is with a coil receiving opening 117 formed in parallel with the valve receiving opening 115 for the control valve 7 is arranged. The sink 400 is in the bobbin receiving opening 117 built-in or added.

The sink 400 includes step areas 423 and 425 at both end regions of the coil 400 in the y-axis direction. The sink 400 further comprises a recess area 424 in a substantially central region of the coil 400 , This recess area 424 is in the entire outer circumference (ie everywhere) of the coil 400 educated. There are also sealing areas 421 and 422 on the outer peripheral surface of the coil 400 on the y-axis facing both sides of the recess area 424 intended. As a result, the spool receiving opening becomes 117 divided into three chambers, namely in a first coil fluid chamber 411 , second coil fluid chamber 412 and third coil fluid chamber 413 , which are sealed against each other liquid-tight.

A feather 401 is in the first coil fluid chamber 411 intended. One end of the spring 401 is with the step area 423 engaged at the negative area of the y-axis of the coil 400 is arranged, and another end of the spring 401 is at the negative end portion of the y-axis of the coil receiving opening 117 fixed. This will make the coil 400 biased in the positive direction of the y-axis. The first coil fluid chamber 411 is connected to the inlet port IN, and thereby the suction pressure in the first coil fluid chamber 411 built up. The first coil fluid chamber 411 is also through the fluid line 7a with the lower pressure chamber C _{L of} the control valve 7 connected.

The second coil fluid chamber 412 and third coil fluid chamber 413 are connected to the outlet port OUT. Thereby, the discharge pressure in the second coil fluid chamber becomes 412 and third coil fluid chamber 413 built so that the coil 400 is biased in the negative direction of the y-axis. The outlet port OUT is with the discharge ports 63 and 122 and the medium pressure chamber Cm connected by liquid lines (not shown).

The second fluid pressure chamber A2 is through a fluid line 24 with the coil receiving opening 117 connected. An opening area 24a the liquid line 24 leading to the coil receiving opening 117 is open, overlap with the recess area 424 in the z-axis direction in a normal state where a sufficient pressure difference is not applied to the spool 400 is applied, provided. In particular, the y-axis positions of both ends of the opening area are 24a the same as the y-axis positions of the two ends of the recess area 424 in normal condition. Consequently, the liquid line 24 through the recess area 424 connected to the outlet port OUT in the normal state.

As the discharge pressure becomes higher and reaches the discharge pressure, the spool moves 400 in the negative direction of the y-axis against the leader by virtue of the spring 401 , This will be the opening area 24a gradually closed or through the sealing area 422 the coil 400 bounded on the positive side of the y-axis of the recess area 424 is arranged. Consequently, the area of the flow passage between the second fluid pressure chamber A2 and the outlet port OUT is reduced (corresponding to the boundary of the metering orifice 110 in the first embodiment), so that the (approximate) pressure difference between the second fluid pressure chamber A2 and the outlet port OUT is effected. This pressure difference moves the control valve 7 so that the pressure Ph of the high pressure chamber C _H in the first fluid pressure chamber A1 is established.

Thereby, the cam ring is swung in the positive direction of the y-axis, so that the discharge rate (discharge amount) and the discharge pressure are reduced. Consequently, the surplus discharge pressure at the time of discharge is reduced in a similar manner as in the first embodiment. The preload force of the spring 401 is set to limit the opening area 24a to start when the discharge pressure is greater than or equal to a predetermined value. Therefore, in this second embodiment, the variable measuring mechanism becomes 100 created using a suitable arrangement. In addition, the excess flow rate is reliably reduced at the time of the discharge pressure.

[Arrangements and effects according to the second embodiment]

• (1) The variable displacement pump in the second embodiment includes the variable metering mechanism 100 , which is the cross-sectional area of the opening area (flow line) of the metering orifice 24a limited when the discharge pressure on the downstream side of the discharge openings 63 and 122 is greater than or equal to a predetermined pressure. Consequently, similar effects as in the first embodiment can be achieved.
• (2) The variable measuring mechanism 100 gets through the coil 400 get the opening area of the metering orifice 24a by the movement according to the measuring aperture 24a controllably changes. Consequently, the variable measuring mechanism 100 easily created.

Further modified examples according to the second embodiment are explained below.

[First Modified Example According to the second embodiment]

12 represents an example in which the coil 400 is provided as an electromagnetic (solenoid) valve. In the non-modified example of the second embodiment explained above, the coil is 400 a mechanical valve that moves based on the delivery pressure. On the other hand, in a first modified example of the second embodiment, the coil becomes 400 created by the electromagnetic valve and with an electromagnetic actuator 500 connected. There will also be a pressure sensor 510 provided for detecting the pressure of the outlet port OUT. The electromagnetic actuator 500 is based on the detected values of the pressure sensor 510 driven, and thereby the opening area 24a limited or locked (according to the orifice plate 110 in the first embodiment, that is, according to the metering orifice according to the present invention). Thus, the variable measuring mechanism becomes 100 receive.

(Arrangements and effects according to the first modified example of the second embodiment)

• (3) The variable measuring mechanism 100 is through the fluid pressure sensor 510 receiving the discharge pressure and the electromagnetic valve based on the detected signal of the liquid pressure sensor 510 is opened. Consequently, a degree of freedom in design and tuning accuracy can be improved because the area of the flow line is due to the movement of the coil 400 is changed electromagnetically.

[Second Modified Example According to the second embodiment]

13 FIG. 14 illustrates an example that further modifies the above-explained first modified example of the second embodiment in such a manner that the purge valve 80 outside the case 11 is provided. In the second modified example of the second embodiment, the purge valve 80 through a fluid line 27 with the second coil fluid chamber 412 the coil 400 and the medium pressure chamber C _M connected. The drain valve 80 is also connected to a reservoir RSV. The drain valve 800 allows only one flow from the liquid line 27 to the reservoir RSV, namely the flow in one direction only.

The second coil fluid chamber 412 the coil 400 is through a fluid line 26 with the discharge openings 63 and 122 connected. In addition, the first coil fluid chamber 411 through a fluid line 28 connected to the inlet port IN.

Because the drain valve 80 outside the control valve 7 is arranged and no aperture between rule the medium pressure chamber C _M and the liquid line 27 is present, the reduction of the pressure of the medium-pressure chamber C _{M is} not reduced due to a narrow shape of the aperture at the time of the Ablasszustandes. This will cause the oscillation of the cam ring 4 suppressed.

In the second modified example of the second embodiment, when the detected value of the pressure sensor 510 reaches the discharge pressure becomes the electromagnetic actuator 500 driven to the coil 400 to move and thereby the liquid line 27 to limit (according to the limiting of the orifice plate 110 in the first embodiment). This will cause the cam ring 4 swinging, so that the excess flow rate is reduced. This eliminates the need for the control valve 7 operate at the discharge condition using the discharge pressure. Thus, the problem also arises with respect to the vibration of the control valve 7 avoided.

[Third Modified Example According to the second embodiment]

14 and 15 represent an example in which the shape of the coil 400 in a way that changes the coil 400 using a bleed pressure that is on a downstream side of the bleed valve 80 is generated, is operated. In a third modified example of the second embodiment, a liquid line 30 on the negative side (end) of the y-axis of the coil 400 provided as in 15 shown. Through this fluid line 30 becomes the coil 400 with the downstream side of the drain valve 80 connected. The feather 401 becomes within the third coil fluid chamber 413 provided, and spans the coil 400 in the negative direction of the y-axis.

In this third modified example, the coil forms 400 a fourth coil fluid chamber 414 within the coil receiving opening 117 in addition to the first to third coil fluid chambers 411 to 413 , Therefore, a volume of the first coil fluid chamber 411 smaller than that of the unmodified example of the second embodiment.

The fourth coil fluid chamber 414 is between the first and second coil fluid chamber 411 and 412 arranged, and through a liquid line 29 connected to the inlet port IN. In addition, the fourth coil fluid chamber 414 with the third coil fluid chamber 413 through a shaft center hole 430 located in a shaft center region of the coil 400 is formed, so that the suction pressure in the third coil fluid chamber 413 is built.

Consequently, when the downstream pressure of the drain valve 80 grows big, the coil moves 400 in the positive direction of the y-axis against the biasing force, so that the opening area of the opening area 24a the liquid line 24 is reduced. Thus, in a similar manner as in the non-modified example of the second embodiment, the surplus discharge pressure at the time of discharge is reduced, and the variable measuring mechanism 100 created using a suitable arrangement. Because also the coil 400 using the pressure on the downstream side of the drain valve 80 is driven, the discharge state is judged or recognized more accurately.

(Arrangements and effects according to the third modified example of the second embodiment)

• (4) The variable measuring mechanism 100 changes the area of the opening area (liquid line) based on the downstream pressure of the drain valve 80 , Consequently, the discharge state can be detected more accurately.
• (5) The variable measuring mechanism 100 gets through the coil 400 which controllably changes the opening area by the float. Consequently, the variable measuring mechanism 100 easily created.

Other Embodiments

Even though the invention with respect to certain embodiments the invention has been described above, the invention is not limited to the embodiments described above. Variations and variants of the embodiments described above appear to the average expert in the light of the above Teaching.

This application is based on the Japanese Patent Application No. 2007-212854 , filed on August 17, 2007. The entire contents of this Japanese patent application are hereby incorporated by reference.

Of the Scope of the invention is with respect to the following claims Are defined.

In summary, the following can be stated:
A variable displacement pump 1 includes a drive shaft 2 ; a rotor 3 that with slits 31 is trained; wing 32 passing through the slots 31 are included; a cam ring 4 that can become eccentric and with the rotor 3 and wings 32 together interacts to define the pump chambers; suction 62 . 121 and discharge openings 63 . 122 which are open to the Pumpenkammem; a sealing element 50 to a space on an outer peripheral surface of the cam ring 4 to divide into first and second fluid pressure chambers; an orifice plate 110 . 24a . 111 on a dispensing line 22 is formed with the discharge opening 63 . 122 connected is; and a pressure control area 7 controlling a pressure built up in the first or second fluid pressure chamber. The pressure control area 7 includes a high-pressure chamber in which an upstream pressure of the metering orifice 110 . 24a . 111 is built, a medium-pressure chamber in which a downstream pressure of the metering orifice 110 . 24a . 111 is constructed, and a low pressure chamber which is connected to a reservoir. The vane pump further includes a drain valve 80 to the downstream pressure of the metering orifice 110 . 24a . 111 drain to the reservoir; and a variable measuring mechanism 100 , which is an area of the orifice plate 110 . 24a . 111 at least limited if the drain valve 80 is open.

1

variable displacement

2

drive shaft

3

rotor

4

cam ring

5

adapter ring or fitting ring

6

printing plate or second plate element

7

control valve or control valve

10

pump body

11

first casing

11a

floor area

11b

Pump element receiving area

12

second casing

21 22, 23, 24, 7a, 26 to 30

 liquid line

22

delivery pipe

22a

opening area

24a

opening area

31

slot

32

wing

33

Back pressure chamber

40

pen

41

inner scope

50

sealing element

51

radial Through Hole

52

Through Hole

53

peripheral surface

61, 120

area

62 121

suction

63 122

discharge opening

71

Kitchen sink

71a

floor area

71b

opening area

71c

sealing area

71d

radial drilling

72

feather

80

drain valve

81

valve body

81a

end

82

valve seat

82a

Through Hole

83

valve ball

84

feather

90

closure element

91

feather

92

piston

100

measuring mechanism

110 24a, 111

orifice

111

Area or minimal protected area

113 116

liquid line

114

Plug-member insertion

115

Valve installation hole

117

Spool installation hole

200

damping orifice

300

pilot orifice

400

Kitchen sink

401

feather

411

First Spool fluid chamber

412

Second Spool fluid chamber

413

third Spool fluid chamber

414

Fourth Spool fluid chamber

421 422

sealing area

423, 425

step region

424

recess portion

430

Shaft center hole

500

electromagnetic actuator

510

pressure sensor

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - JP 2003-21076 [0002]
• - JP 2007-212854 [0117]

Claims (20)

Variable displacement vane pump comprising: - a pump body ( 10 ); A drive shaft ( 2 ) passing through the pump body ( 10 ) is supported rotatably; A rotor ( 3 ) inside the pump body ( 10 ) is arranged and by the drive shaft ( 2 ) is rotatably driven, wherein the rotor ( 3 ) with a plurality of slots ( 31 ) separated from each other in the circumferential direction of the rotor ( 3 ) is formed, is formed; A plurality of wings ( 32 ); through the slots ( 31 ) so as to be separated from the slots ( 31 ) away and into the slots ( 31 ) to be mobile; A cam ring ( 4 ) formed in an annular shape and within the pump body ( 10 ) is arranged to the cam ring ( 4 ), with respect to the drive shaft ( 2 ) eccentric, wherein the cam ring ( 4 ) with the rotor ( 3 ) and the wings ( 32 ) cooperates to a plurality of pump chambers (B) on an inner peripheral side of the cam ring ( 4 ) define; A first plate element ( 12 ) and a second plate element ( 6 ), which on the two axial sides of the cam ring ( 4 ) are arranged; A suction opening ( 62 . 121 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A discharge opening ( 63 . 122 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A sealing element ( 50 ), which on an outer peripheral side of the cam ring ( 4 ), wherein the sealing element ( 50 ) a space on an outer peripheral surface of the cam ring (FIG. 4 ) in a first fluid pressure chamber (A1) and a second fluid pressure chamber (A2) divides, wherein a flow rate of the working fluid, the voltage from the Ausgaböff ( 63 . 122 ) is increased, when the cam ring ( 4 ) to the first fluid pressure chamber (A1), wherein the flow rate of the working fluid coming from the discharge port (A1) 63 . 122 ) is reduced, when the cam ring ( 4 ) is moved to the second fluid pressure chamber (A2); - an orifice plate ( 110 . 24a . 111 ) located on a delivery line ( 22 ) is formed with the discharge opening ( 63 . 122 ) connected is; A pressure control area ( 7 ) controlling a pressure built up in the first fluid pressure chamber (A1) or the second fluid pressure chamber (A2), the pressure control range (FIG. 7 ) Comprises: - a high-pressure chamber (C _H ), in which an upstream pressure of the metering orifice (C _H ) 110 . 24a . 111 ), - a medium pressure chamber (C _M ), in which a downstream pressure of the orifice ( 110 . 24a . 111 ), and a low pressure chamber (C _L ) connected to a reservoir (RSV) for storing the working fluid; - a drain valve ( 80 ) located between a downstream side of the orifice plate ( 110 . 24a . 111 ) and the reservoir (RSV) is arranged, wherein the drain valve ( 80 ) is opened by receiving a pressure which is greater than or equal to a predetermined level, and thereby the downstream pressure of the orifice plate ( 110 . 24a . 111 ) to the reservoir (RSV); and a variable measuring mechanism ( 100 ), which has a cross-sectional area of the opening area of the metering orifice ( 110 . 24a ) is at least limited when the drain valve ( 80 ) is open. Variable displacement pump according to claim 1, wherein - the cam ring ( 4 ) so as to gradually increase the opening area of the metering orifice ( 110 ), whereby the variable measuring mechanism ( 100 ) through the measuring aperture ( 110 ) and the cam ring ( 4 ) is received; and - the metering orifice ( 110 ) has the opening area formed in an axial end face of the first plate member (Fig. 12 ) or second plate element ( 6 ) is trained. Variable displacement pump according to claim 2, wherein - the variable measuring mechanism ( 100 ) the opening area of the metering orifice ( 110 ) is gradually limited after the cam ring ( 4 ) is swung to its position at a predetermined angle. Variable displacement pump according to claim 2, wherein - a circumferential width of the opening area of the metering orifice ( 110 ) is greater than a radial width thereof. Variable displacement pump according to claim 4, wherein - the opening area of the metering orifice ( 110 ) is formed in an elliptical shape or slot shape. Variable displacement pump according to claim 4, wherein - the measuring diaphragm ( 110 ) a plurality of openings ( 110 . 111 ) having. Variable displacement pump according to claim 2, further comprising: - a pilot diaphragm ( 300 ) on a line ( 21 ) is arranged, which the discharge opening ( 63 . 122 ) connects to the high pressure chamber (C _H ). Variable displacement pump according to claim 2, the further comprising: - a damping diaphragm ( 200. ) on a line ( 116 ) is arranged, which the orifice plate ( 110 ) connects to the medium pressure chamber (C _M ). Variable displacement pump according to claim 1, wherein - the variable displacement pump further comprises a piston ( 92 ) in response to a vibration of the cam ring ( 4 ) emotional; and - the metering orifice ( 110 ) in the piston ( 92 ) is trained. Variable displacement pump according to claim 1, wherein - the variable measuring mechanism ( 100 ) the area of the opening area of the metering orifice ( 24a ) on the basis of a downstream pressure of the drain valve ( 80 ) changed. Variable displacement pump according to claim 10, wherein - the variable measuring mechanism ( 100 ) through a coil ( 400 ), which covers the area of the opening area of the metering orifice ( 24a ) by the movement with respect to the metering orifice ( 24a ) controllably changed. Variable displacement vane pump comprising: - a pump body ( 10 ); A drive shaft ( 2 ) passing through the pump body ( 10 ) is supported rotatably; A rotor ( 3 ) inside the pump body ( 10 ) is arranged and by the drive shaft ( 2 ) is rotatably driven, wherein the rotor ( 3 ) with a plurality of slots ( 31 ) separated from each other in the circumferential direction of the rotor ( 3 ) is formed, is formed; A plurality of wings ( 32 ); through the slots ( 31 ) so as to be separated from the slots ( 31 ) away and into the slots ( 31 ) to be mobile; A cam ring ( 4 ) formed in an annular shape and within the pump body ( 10 ) is arranged to the cam ring ( 4 ), with respect to the drive shaft ( 2 ) eccentric, wherein the cam ring ( 4 ) with the rotor ( 3 ) and the wings ( 32 ) cooperates to a plurality of pump chambers (B) on an inner peripheral side of the cam ring ( 4 ) define; A first plate element ( 12 ) and a second plate element ( 6 ), which on the two axial sides of the cam ring ( 4 ) are arranged; A suction opening ( 62 . 121 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A discharge opening ( 63 . 122 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A sealing element ( 50 ), which on an outer peripheral side of the cam ring ( 4 ), wherein the sealing element ( 50 ) divides a space on an outer peripheral surface of the cam ring (4) into a first fluid pressure chamber (A1) and a second fluid pressure chamber (A2), wherein a flow rate of the working fluid discharged from the discharge port ( 63 . 122 ) is increased, when the cam ring ( 4 ) to the first fluid pressure chamber (A1), wherein the flow rate of the working fluid coming from the discharge port (A1) 63 . 122 ) is reduced, when the cam ring ( 4 ) is moved to the second fluid pressure chamber (A2); - an orifice plate ( 110 . 24a . 111 ) located on a delivery line ( 22 ) is formed with the discharge opening ( 63 . 122 ) connected is; A pressure control area ( 7 ) controlling a pressure built up in the first fluid pressure chamber (A1) or the second fluid pressure chamber (A2), the pressure control range (FIG. 7 ) Comprises: - a high-pressure chamber (C _H ), in which an upstream pressure of the metering orifice (C _H ) 110 . 24a . 111 ), - a medium pressure chamber (C _M ), in which a downstream pressure of the orifice ( 110 . 24a . 111 ), and a low pressure chamber (C _L ) connected to a reservoir (RSV) for storing the working fluid; - a drain valve ( 80 ) located between a downstream side of the orifice plate ( 110 . 24a . 111 ) and the reservoir (RSV) is arranged, wherein the drain valve ( 80 ) is opened by receiving a pressure which is greater than or equal to a predetermined level, and thereby the downstream pressure of the orifice plate ( 110 . 24a . 111 ) to the reservoir (RSV); and a variable measuring mechanism ( 100 ), which has a cross-sectional area of the opening area of the metering orifice ( 110 . 24a ) is limited when a discharge pressure on a downstream side of the discharge opening ( 63 . 122 ) is greater than or equal to a predetermined pressure. Variable displacement pump according to claim 12, wherein - the variable measuring mechanism ( 100 ) by a liquid pressure sensor ( 510 ) coming from the discharge opening ( 63 . 122 ) and an electromagnetic valve ( 400 . 500 ) based on a detected signal from the fluid pressure sensor ( 510 ) is received. Variable displacement pump according to claim 12, where - the variable measuring mechanism ( 100 ) through a coil ( 400 ), which covers the area of the opening area of the metering orifice ( 24a ) by the movement with respect to the metering orifice ( 24a ) controllably changed. Variable displacement vane pump comprising: - a pump body ( 10 ); A drive shaft ( 2 ) passing through the pump body ( 10 ) is supported rotatably; A rotor ( 3 ) inside the pump body ( 10 ) is arranged and by the drive shaft ( 2 ) is rotatably driven, wherein the rotor ( 3 ) with a plurality of slots ( 31 ) separated from each other in the circumferential direction of the rotor ( 3 ) is formed, is formed; A plurality of wings ( 32 ); through the slots ( 31 ) so as to be separated from the slots ( 31 ) away and into the slots ( 31 ) to be mobile; A cam ring ( 4 ) formed in an annular shape and within the pump body ( 10 ) is arranged to the cam ring ( 4 ), with respect to the drive shaft ( 2 ) eccentric, wherein the cam ring ( 4 ) with the rotor ( 3 ) and the wings ( 32 ) cooperates to a plurality of pump chambers (B) on an inner peripheral side of the cam ring ( 4 ) define; A first plate element ( 12 ) and a second plate element ( 6 ), which on the two axial sides of the cam ring ( 4 ) are arranged; A suction opening ( 62 . 121 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A discharge opening ( 63 . 122 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A sealing element ( 50 ), which on an outer peripheral side of the cam ring ( 4 ), wherein the sealing element ( 50 ) a space on an outer peripheral surface of the cam ring (FIG. 4 ) into a first fluid pressure chamber (A1) and a second fluid pressure chamber (A2), wherein a flow rate of the working fluid discharged from the discharge port (A1) 63 . 122 ) is increased, when the cam ring ( 4 ) to the first fluid pressure chamber (A1), wherein the flow rate of the working fluid coming from the discharge port (A1) 63 . 122 ) is reduced, when the cam ring ( 4 ) is moved to the second fluid pressure chamber (A2); - an orifice plate ( 110 . 24a . 111 ) located on a delivery line ( 22 ) is formed with the discharge opening ( 63 . 122 ) connected is; A pressure control area ( 7 ) controlling a pressure built up in the first fluid pressure chamber (A1) or the second fluid pressure chamber (A2), the pressure control range (FIG. 7 ) Comprises: - a high-pressure chamber (C _H ), in which an upstream pressure of the metering orifice (C _H ) 110 . 24a . 111 ), - a medium pressure chamber (C _M ), in which a downstream pressure of the orifice ( 110 . 24a . 111 ), and a low pressure chamber (C _L ) connected to a reservoir (RSV) for storing the working fluid; - a drain valve ( 80 ) located between a downstream side of the orifice plate ( 110 . 24a . 111 ) and the reservoir (RSV) is arranged, wherein the drain valve ( 80 ) is opened by receiving a pressure which is greater than or equal to a predetermined level, and thereby the downstream pressure of the orifice plate ( 110 . 24a . 111 ) to the reservoir (RSV); and a variable measuring mechanism ( 100 ), which has a cross-sectional area of the opening area of the metering orifice ( 110 . 24a ) is limited to a greater extent when the eccentricity of the cam ring ( 4 ) becomes smaller when the drain valve ( 80 ) is open. Variable displacement vane pump according to claim 15, wherein - the cam ring ( 4 ) oscillates, in order thus to open the aperture area of the measuring aperture ( 110 ), whereby the variable measuring mechanism ( 100 ) through the measuring aperture ( 110 ) and the cam ring ( 4 ) is received; and - the metering orifice ( 110 ) has the opening area formed in an axial end face of the first plate member (Fig. 12 ) or second plate element ( 6 ) is trained. Variable displacement pump according to claim 15, wherein - the variable measuring mechanism ( 100 ) the opening area of the metering orifice ( 110 . 24a ) is gradually limited after the cam ring ( 4 ) is swung to its position at a predetermined angle. Variable displacement pump according to claim 15, further comprising: - a pilot diaphragm ( 300 ) on a line ( 21 ) is arranged, which the discharge opening ( 63 . 122 ) connects to the high pressure chamber (C _H ). Variable displacement vane pump comprising: - a pump body ( 10 ); A drive shaft ( 2 ) passing through the pump body ( 10 ) is supported rotatably; A rotor ( 3 ) inside the pump body ( 10 ) is arranged and by the drive shaft ( 2 ) is rotatably driven, wherein the rotor ( 3 ) with a plurality of slots ( 31 ) separated from each other in the circumferential direction of the rotor ( 3 ) is formed, is formed; A plurality of wings ( 32 ); through the slots ( 31 ) so as to be separated from the slots ( 31 ) away and into the slots ( 31 ) to be mobile; A cam ring ( 4 ) formed in an annular shape and within the pump body ( 10 ) is arranged to the cam ring ( 4 ), with respect to the drive shaft ( 2 ) eccentric, wherein the cam ring ( 4 ) with the rotor ( 3 ) and the wings ( 32 ) cooperates to a plurality of pump chambers (B) on an inner peripheral side of the cam ring ( 4 ) define; A first plate element ( 12 ) and a second plate element ( 6 ), which on the two axial sides of the cam ring ( 4 ) are arranged; A suction opening ( 62 . 121 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A discharge opening ( 63 . 122 ) located on one side of at least one of the first plate elements ( 12 ) or second plate element ( 6 ) and opened to at least one of the plurality of pump chambers (B); A sealing element ( 50 ), which on an outer peripheral side of the cam ring ( 4 ), wherein the sealing element ( 50 ) a space on an outer peripheral surface of the cam ring (FIG. 4 ) into a first fluid pressure chamber (A1) and a second fluid pressure chamber (A2), wherein a flow rate of the working fluid discharged from the discharge port (A1) 63 . 122 ) is increased, when the cam ring ( 4 ) to the first fluid pressure chamber (A1), wherein the flow rate of the working fluid coming from the discharge port (A1) 63 . 122 ) is reduced, when the cam ring ( 4 ) is moved to the second fluid pressure chamber (A2); - an orifice plate ( 24a ) located on a delivery line ( 22 ) is formed with the discharge opening ( 63 . 122 ) connected is; A pressure control area ( 7 ) controlling a pressure built up in the first fluid pressure chamber (A1) or the second fluid pressure chamber (A2), the pressure control range (FIG. 7 ) Comprises: - a high-pressure chamber (C _H ), in which an upstream pressure of the metering orifice (C _H ) 24a ), - a medium pressure chamber (C _M ), in which a downstream pressure of the orifice ( 24a ), and a low pressure chamber (C _L ) connected to a reservoir (RSV) for storing the working fluid; A fluid pressure sensor ( 510 ), one from the delivery port ( 63 . 122 ) detected pressure detected; - a drain valve ( 80 ), the downstream pressure of the orifice plate ( 24a ) to the reservoir (RSV), and using a pressure to move the device from the discharge port ( 63 . 122 ) to apply applied pressure; and a variable measuring mechanism ( 100 ) to a cross-sectional area of the flow line of the orifice plate ( 24a ) based on an output signal of the fluid pressure sensor ( 510 ) to limit. Variable displacement pump according to claim 19, wherein - the variable measuring mechanism ( 100 ) by an electromagnetic valve ( 400 . 500 ) based on the output of the fluid pressure sensor ( 510 ) is opened.