US1970530A - Hydraulic actuating mechanism - Google Patents

Description

. Aug. 14, 1934.

n. H. was-r I HYDRAULIC ACTUATING MECHANISM 7 Sheets-Sheet '1 Filed Nov. 11, 1930 22 a JazzaZiZ wa Aug. 14, 1934.

D. H. WEST HYDRAULIC ACTUATING MECHANISM Filed Nov. 11, 1930 7 Sheets-Sheet 2 jazaid E r Aug. 14, 1934. n. H. WEST HYDRAULIC ACTUATING MECHANISM '7 Sheets-Sheet 3 Filed Nov. 11, 1930 7 Sheets-Sheet 4 J7??? ar' Filed Nov. 11, 1930 Q h A Aug. 14, 1934.

1:. H. WEST HYDRAULIC ACTUATING MECHANISM 7 Sheets-Sheet 5 Filed Nov. 11, 19:50

7 Sheets-She 6 .Zkzgfan D.I1.VVEE?T Filed Nov. 11, 1950 flwzaid 72? Ma?!" Aug. 14, 1934.

HYDRAULIC ACTUATING MECHANISM &

Aug. 14,1934. 0. H. WEST HYDRAULIC ACTUATING MECHANISM Filed Nov. 11, 1930 7 Sheets-Sheet 7 55 unison with the cylinder block 14. Thecasing Patented Aug. 14, 1934 UNITED STATES PATENT OFFICE 1; Claims.

This invention relates to mechanism by which a reciprocated member may be hydraulically actuated at different selected speeds.

' I It is the object of my invention to provide improved mechanism for such purposes which includes a constant delivery pump which may be set for two predetermined rates of discharge and which also includes a low pressure pump having a delivery automatically varied to maintain constant pressure.

My invention also relates to means for connecting these pumps in various combinations to the mechanism to be driven, so that said mechanism may be actuated at different selected speeds.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in which Fig. 1 is an end elevation of my improved hydraulic mechanism;

Fig. 2 is a sectional side elevation, taken along the line 22 in Fig. 1;

Fig. 3 is a diagrammatic view'ol! the control devices for my improved hydraulic mechanism, and

Figs. 4, 5, 6 and '1 are views similar to Fig. 3 but showing diilferent conditions of operation.

Referring particularly to Figs. 1 and 2, my improved hydraulic apparatus includes pumping mechanism assembled within a casing 10. A drive shaft 12 is rotated from any convenient source of power and is mounted in an antifriction bearing 13 supported by a side wall of the casing 10.

A multiple plunger rotary pump is actuated by the shaft 12 and comprises a cylinder block 14 fixed to the end of the shaft 12 and rotatable upon a stationary port member 15 extending inward from the second side wall of the casing 10. An anti-friction bearing 16 may be provided between the cylinder block 14 and a reduced projecting portion 1'1 of the port member 15.

The block 14 has a plurality of cylinders 20 in which pistons 21 are slidably mounted. These pistons 21 are actuated by links 22 having spherical heads 23 mounted in bearings in a rotatable member 25. The rotatable member 25 is mounted on an anti-friction bearing 26, which in turn is mounted in a casing 2'1.

The member 25 is connected by pivot pins to the driving shaft 12, so that it rotates in 27, however, is held from rotation and is positioned at an oblique angle to the axis of the shalt 12. Consequently the pistons 21 will be 60 pushed into and withdrawn from the cylinders 20 as the cylinders and pistons rotate in unison about the axis of the shalt 12. The intake 01 the low pressure pump is indicated at 33 (Figs. 1 and 3) and the discharge or outlet is indicated at 34.

Stops 35 and 36 (Fig. 2) limit the rocking movement of the casing 2'7 which is normally maintained in contact with the stop 35, as shown in Fig. 2, by a relatively heavy spring 38 acting against a fixed abutment 39 and connected by a link 40 to an ear 41 projecting upwardly from the casing 2'71 A similar ear 42 at the opposite or lower side of the casing is connected by a link 43 to a plunger 44 slidable in a cylinder 45 in the casing 10'. This cylinder is at all times connected by a pipe 46 to the delivery side of the low pressure pump, as clearly indicated in Figs. 1 and 3. 1

Consequently the delivery pressure of the low pressure pump acts continuously against the piston or plunger 44. If this pressure exceeds a predetermined amount, it will overcome the spring 38 and will rock the casing 27 toward a position perpendicular to the axis of the shaft 12, thus reducing the strokeof the pump pistons 21 and correspondingly reducing the rate of delivery or discharge of the pump.

The stop '36 acts merely to limit such ratereducing movement of the casing 27 by the plunger 44, so that a certain minimum discharge is continuously maintained.

A high pressure pump is mounted in the upper part ofthe casing, where a second drive shaft 50 is rotatably supported and isconnected by sprockets 51 and 52 and a silent chain 53 to the lower drive shaft 12. A multiple plunger pump is mounted concentric with the upper drive shaft 50 and is actuated thereby, the pump being essentially similar in construction to the low pressure pump previously. described. The plungers of the high pressure pump are provided with pistons of substantially reduced size, so that the capacity of the high pressure pump is much less than that of the low pressure pump.

The casing 55 of the high pressure pump is provided with ears. 56 and 57 and one car 56 is.

connected by a link 58 to a plunger 53 slidable in a cylinder 60 in the casing 10. Inward sliding movement of the plunger 59 is adiustably limited by a stop screw 61. The second car 57 is similarly connected by a link 62 to a. plunger 63 slidable in a cylinder 64 and provided with an adjustable stop screw 65.

The discharge outlet of the high pressure pump is indicated at 66in Figs. 1 and 3 and the intake of the pump is indicated at. 67. It will be noted that the high pressure intake 67 is directly connected to the low pressure discharge 34 by a pipe 68 3) so that the two pumps work in series. The upper control cylinder so ls connected by a pipe '10 (Fig. 3) to certain valve mechanism tobe described and the lower control cylinder 64 is similarly connected ,nected to the exhaust pipe 94 by which the fluid is returned to the suction intake 33 of the to the valve mechanism through a pipe 71.

If excess pressure is applied through the pipe to the control chamber 60, the plunger 59 will be pushed outward and the plunger 63 will move inward until the plunger 63 engages the stop screw 65, thus rocking the casing 55 to its position of greatest inclination and giving the high pressure pump its predetermined maximum discharge capacity.

Ii,- on the other hand, excess pressure is appliedthrough the pipe 71 to the control chamber 64, the plunger 63 is forced outward and the plungerv 59 inward until the plunger 59 engages the stop screw 61, with the. casing 55 at its smallest angle of displacement, in which position the high pressure pump will operate at its lowest predetermined discharge capacity.

The mechanism to be operated by the pumps above described may -be of any desired type and is indicated in the drawings simply as a piston is provided with spaced pistons 78, 79, 80, 81- and 82. The valve rod may be actuated manually or in any other convenient manner and an indicator 83 may be connected to one end thereof, positioned to cooperate with certain insignia on an.

index plate 84.

The low pressure discharge outlet 34 is connected by a pipe 85 to an annular port in the wall of the cylinder 76. The high pressure discharge opening 66 is similarly connected by a pipe 86 to a similar annular port 87 in the wall of the cylinder 76. The port 87 is connected by aby-pass 88 to a second annular port 89, also in the wall of the cylinder 76. The pipes 70, 72 and 73 previously described are similarly connected to annular ports of the cylinder 76 and the pipe 71 is connected to an annular port 90, which in turn is connected by a by-pass 91 to an additionalannular port 92.

An exhaust passage 93 extends alongside the cylinder 76 and is connected toa series of exhaust ports, as clearly indicated in the drawings. The passage 93 is also connected to an exhaust or return pipe 94 by which the exhaust fluid is returned to a tank and thence to the suction inlet 33 of the low pressure pump.

7 Rapid approach ation is asfollows: The low pressure pump dethrough the pipe 86 to thesame portion 01' the cylinder'76, thus increasing the amount of fluid delivered to the operating cylinder.

The discharge end of the cylinder 71 is connected through the pipe 73 to the space between the pistons 81 and 82 and thence through an open port to the discharge passage '93. con- In the position shown in Fig. 3, fluid at low pressure is conducted through the passage 96 and port 97 to the cylinder space between the;

pistons 79 and and thence through the pipe 70 to the control chamber 60 of the high pressure pump. At the same time, the control chamv ber 64 is connected through thepipe 71 and port to the space between the pistons 78 and 79 and thence to the exhaust passage 93.

As there is thus low pressure in the chamber 60, while the chamber 64 is connected to the exhaust, the casing 55 will be moved to the position of maximum delivery indicated in Fig. 2.

Intermediate speed In Fig. 4, I have indicated the position of the parts when operating the piston 70 in the direction of the arrow a. at an intermediate or #1 speed. Under these conditions, the low pressure delivery pipe 85 is closed by the 'piston 81 but the high" pressure delivery pipe 86 is still connected to the feed pipe 72 at the left hand end of the cylinder 71' while the pipe 73 remains connected to the exhaust. Furthermore, the connections to the high pressure control cylinders 60 and 64 remainunchanged, so that under these conditions the low pressure pump acts in series with the high pressure pump but the rate of delivery is that of the high pressure pump at its maximum setting.

The discharge of the low pressure pump also acts through the pipe 46 against the piston 44 (Fig. 2) andthus moves the rocking casing 27 toward neutral "position until the discharge of the low pressure pump is just sufiicient to supply the high pressure pump. The rocking casing is automatically maintained at this setting by the balanced action of the piston 44 against the spring 38.

z Slow speed movement In Fig." 5 I have indicated the setting of the valve mechanism for the slow feed or #2 movement of the piston 70 in thedirection of the arrow (1. The low pressure delivery pipe 85 is still closed by the piston 81 and the high pressure pipe 86 is still connected through the feed pipe 72 to the left hand end of the cylinder 71", while the pipe 73 and right hand end remains connected to the exhaust. h

It will be noted, however, that the port 97 of the branch passage 96 from the low pressure pump is now closed by the piston 80, while the port 98 previously closed by the piston 78 is now open. Consequently low pressure will be applied through the pipe 71 to the lower control chamber 64, while the upper control chamber 60 is connected through the pipe 70 to the exhaust. Consequently the casing 55 will be rocked to-its position of least inclination, -and-- the rate of discharge of the high pressure pump will be at a minimum. Consequently the piston 7.0 will be given a very slow speed operating movement. The discharge of the low pressure pump will be maintained at the point justsufflcient-to-supply the high pressure pump at its minimum discharge through the balanced action of the piston 44 and spring 38 as previously described.

, Neutral position In'.Fig.6,' I haveindicated a position of the. parts such that the piston '70 will be held without movement in either direction. The pipe '72 from the left hand end of the cylinder '71 is now connected to the space between the pistons 80 ,and 81, for which space there is neither entrance nor exit in this setting of the valve mechanism. v

The low pressure supply pipe 85 is blocked or: by the piston 81 but the high pressure supply pipe 86 is connected through the by-pass 88 to the space between the pistons 81 and 82 and thence to theexhaust. The pipe 73 is also open 'to this same cylinder space but no flow of fluid will take placeinto the right hand end of the cylinder 71, as the high pressure pump, being directly connected to the exhaust, cannot build up any pressure. Furthermore the fluid in the left hand portion of the cylinder cannot be forced out, as the pipe '72 connects to a closed cylinder space. Consequently the piston 70 will'remain in fixed or neutralized position.

It may be further notedthat in this position 'the high pressure-control'pipes 70 and '71 are both closed so that the high pressure pump remains set for low volume delivery.

Rapid return movement nects to the cylinder space between the pistons furthermore so that a 81-and 82 and thence through the feed pipe l3 to the right hand end of the cylinder 71. At the same time the high pressure delivery pipe 86 is connected through the by-pass 88 ,to the same cylinder space between the pistons 81 and 82.

The left hand end of thecylinder 71'- is connected through the pipe '12 to the space between the pistons 80 and 81 and thence to the ex- -haust. The high pressure control pipe is blocked off by the piston and the branch connection 96 is connected-through the by-pass 91 to the control pipe 71, so that-the high pressure pump continues to operate at minimum discharge.

' Conclusion I Having described the details of construction and the various methods of operation of my improved hydraulic mechanism, it will be evident that I have provided a construction comprising a low pressure pump automatically controlled to deliver a large volume of fluid at a predetermined pressure, and a high pressure pump automatically controlled to deliver fluid at either one of two predetermined rates of discharge.

.1 have also provided control mechanism by which the pumps may be variably connected .to the mechanism to be operated, so that the actuated element may be given a rapid approach movement; so that the high pressure pump may operate at maximum predetermined capacity for an intermediate working speed; so thatthe high pressure pump may operate at a lower prede termined capacity tor a slow working speed; so that the driven mechanism may be maintained without ,movement in a desired position: and rapid return movement maybe obtained.

Having thus described my invention and the advantages thereof, 1 do not wish to be limited to the details herein disclosed,"otherwi'se than as set forth in the claims, but what I claim is:-

1. A pumping system adapted to deliver fluid to a receiver, said system comprising, a low pressure pump, a high pressure pump, means tocause said high pressure pump to deliver liquid ata. high or a low predetermined rate, connections between said pumps and said-receiver, and control valve mechanism effective in different operative positions to operatively connect said pumps in difierent combinations with said receiver and to selectively determine the rate of delivery of the high pressure pump.

2. A pumping system adapted to deliver fluid to a receiver, said system comprising, a .low pressure pump, a high pressure pump-means to cause said high pressure pump to deliver liquid.

at a high or a low predetermined rate, connections between said pumps and said receiver, and

control valve mechanism effective in difierent operative positions to .operatively connect said pumps withsaid receiver so that liquid will be delivered to said receiyer jointly by'said low pressure pump and by said high pressure pump at its higher rate of delivery, or by said high pressure pump only at its high or its low rate of delivery.

3. A pumping system adapted to deliver fluid to a receiver, said system comprising, a low pressure pump, a high pressure pump, means to cause said high pressure pump to deliver liquid at ahigh or a low predetermined rate, connections between both of said-pumps and said receiver, and control valve mechanism eflective in diiferent operative positions to operatively connect said pumps with said receiver so that liquid will be delivered to said receiver by said high pressure pump only at its high or its low rate of delivery, at the same time causing the low pressure pump to operate at reduced capacity in series with said high pressure pump, or so that said pumps will deliver in parallel to said receiver.

4. The combinationdn a pumping system as set forth in claim 2, in which the rate-controlling means for the highpressure pump is op-.- erated throughhydraulic connections from 'said control valve mechanism.

ling means forthe high pressure pump is operated in both directions through hydraulic econ'nections from said control valve mechanism.

6. A pumping system adapted to deliver fluid 5. The combination in a pumping system as set forth in claim 2. in which the rate-controlat its higher rate oi. delivery, or by said high pressure pump only at its high or its low rate of delivery, and means to vary the discharge of said low pressure pump livery pressure.

. DONALD E. WEST.

to maintain constant de-

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