JP2503065B2 - Electric pump - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electric pump for pumping oil or the like, and more particularly to a pump in which a radial load is applied to an output shaft.

[Conventional technology]

Conventionally, an electric pump in which a plunger operates in a radial direction of an output shaft is known.

In this type, the motor unit is first assembled, and then the motor unit and the pump unit are connected to each other, and the output shaft is supported by bearings provided on both end surfaces of the motor housing.

[Problems to be Solved by the Invention]

In the above configuration, there is a problem that the distance between the two bearings becomes long and the output shaft is easily bent by the pump load.

In addition, the load applied to the output shaft also acts on the bearing on the side opposite to the pump part, so it is necessary to use high-strength members for the motor yoke and end frame of the motor part. There is a problem that you cannot do it.

Further, it is necessary to process the motor yoke and the end frame to which the bearing is attached with high precision, and also the high precision is required for coupling the motor and the pump, so that the machining process is complicated and the workability is poor.

The present invention is intended to solve the above problems, and an object thereof is to prevent the deflection of the output shaft, reduce the size and weight of the motor portion, and simplify the machining process.

[Means for solving the problem]

The present invention relates to a pump housing provided with a pump portion for pumping a fluid, an output shaft provided with a pump driver for driving the pump portion at one end side, and an output shaft fixed to the pump housing for the previous term. A motor unit provided on the other end side of the shaft, and by driving the output shaft by the motor unit,
In an electric pump that pumps fluid by the pump section, in the pump housing, two bearings that rotatably support one end side of the output shaft with the pump driving body interposed therebetween are provided, and the other end side of the output shaft is provided. The technical means is adopted so that the bearing is not supported by the bearing.

[Action]

According to the above configuration, since two bearings are provided in the pump housing with the pump driver interposed therebetween, the distance between the bearings is extremely short, the pump load is distributed to these bearings, and the deflection of the output shaft is reduced. .

Further, the motor side output shaft end opposite to the pump part is not supported by the bearings, and it is not necessary to form the motor yoke and the end frame as high-strength members, so that the size and weight of the motor can be reduced. Further, the high-precision machining of the motor yoke and the end frame can be simplified, and the workability is improved.

〔Example〕

The present invention will be described below with reference to the embodiments shown in the drawings. First
In the figure, reference numeral 10 denotes a pump housing which is formed into a substantially cylindrical shape by aluminum die casting or the like, and has a suction hole 12 for oil to be pumped and a discharge hole 14 for oil. Further, the pump housing 10 is provided with a plurality of pump portions 16 in the radial direction thereof. The pump portion 16 includes a plunger support 18 provided on the pump housing 10 and the support.
A plunger 20 reciprocatingly provided in 18 and having a flow path in the center, a coil spring 22 for pressing the plunger 20,
Balls 24 and 26 that make up the check valve, coil springs 28 and 30,
The spring holder 32, the plurality of O-rings for sealing, and the plug member 34 are included, but the detailed structure thereof is publicly known, and thus the description thereof is omitted.

Next, the motor section will be described. The motor unit 40 is configured as a magnet type DC motor, and includes an output shaft 42, a flat rotor 44 provided on the output shaft 42, and a commutator 46 provided on the right end side of the output shaft 42 in the figure. There is.

Further, the motor unit 40 is fixed to the end face of the motor yoke 48, the cylindrical motor yoke 48 fixed to the pump housing 10, the arc-shaped magnet 50 fixed inside the motor yoke 48 so as to face the rotor 44. Holding plate 52, this holding plate 52
A brush 54 provided so as to slidably contact the commutator 46,
An end frame 56 and a rubber waterproof cover 58, which are fixed by caulking so as to cover the end surface of the motor yoke 48, are provided.

Here, the pump housing 10 is formed with a circular step portion 60, and the motor yoke 48 is fitted into the step portion 60 via an O-ring 62. An eccentric cam (pump drive body) 64 for driving the plunger 20 is fixed to the output shaft 42 by press fitting at the left end of the output shaft 42 in the drawing. A small bearing 66 and a large bearing 68 on the right side are fixed to the output shaft 42 by press fitting.

The eccentric cam 64 has a needle bearing structure,
The bearings 66, 68 have a ball bearing structure, are provided in a central hole 70 having a stepped diameter in the pump housing 10, and a washer 72 restricts movement of the pump housing 10 in the axial direction. This washer 72 is the second
As shown in the figure, the protrusion 10a of the pump housing 10 is partially caulked, and the pump housing 1 is
Fixed to 0. It is also preferable to insert a wave washer between the left end surface of the bearing 66 in the drawing and the pump housing.

Next, the assembly sequence of the motor unit will be described with reference to FIGS. 3 and 4. Here, the pump housing 10 also serves as a motor housing, and the motor portion is assembled to the pump housing 10.

First, the small bearing 66, the eccentric cam 64, and the large bearing 68 are inserted into the center hole 70 of the pump housing 10 in this order, and the washer 72 is fixed.

Next, as shown in FIG. 4, the inner ring of the bearing 66 is supported by a jig 80 having a through hole in the center, and the bearing 66, 66 is supported by a rod-shaped jig 82 inserted into the through hole of the jig 80. 68, the eccentric cam 64 is positioned, and the output shaft 42 is mounted on the bearings 66, 68,
Press into the eccentric cam 64.

Next, the motor yoke 48 is fixed to the pump housing 10, the holding plate 52 is fixed to the motor yoke 48 together with the brush 54, and the end frame 56 is fixed to the motor yoke 48 by caulking.

As described above, since the parts of the motor section are assembled in the pump housing 10 from one direction so that the parts are assembled, the workability of assembling the motor is improved.

Next, the operation will be described. In the motor section, a current from a power source (not shown) is supplied to the rotor 44 via the brush 54 and the commutator 46 to rotate the rotor. This allows
The output shaft 42 rotates and the eccentric cam 64 rotates. Eccentric cam 64
The blanker 20 that is in contact with the reciprocating body reciprocates in the radial direction, and the reciprocating movement causes the oil to be sucked from the suction hole 12.
It is discharged from the discharge hole 14.

At this time, a considerable pump load is applied to the output shaft 42 via the eccentric cam 64, but this is received by the bearings 66, 68 arranged on both sides of the eccentric cam 64, and the deflection of the output shaft 42 is reduced. Also, because of this, the pump load is
Is not transmitted to the motor side end portion (right side in the figure) 42a, and the right end 42a is not supported by the bearing at all, the motor yoke 48 and the end frame 56 do not need to be high-strength members, and the motor portion is small.・ Lighter weight is possible.The eccentric cam 64 and the output shaft 42 are the pump housing.
This structure is directly attached to the structure 10. This structure improves the positional accuracy of the pump portion and the output shaft 42, and can reduce the accuracy of the motor yoke 48 and the end frame 56, thus simplifying the machining process.

Although the pump portion is of the plunger type in the above embodiment, it may be a radial pump of another type.

〔The invention's effect〕

As described above, according to the present invention, the output shaft is less likely to bend, the size and weight of the motor unit can be reduced, the machining process can be simplified, and the workability can be improved.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an embodiment of the present invention, FIG. 2 is a view taken along the line AA of FIG. 1, and FIGS. 3 and 4 show the motor section shown in FIG. It is an assembly lineblock diagram showing an assembling method. 10 …… Pump housing, 16 …… Pump section, 20 …… Plunger, 40 …… Motor section, 42 …… Output shaft, 42a …… End section, 64…
… Eccentric cam, 66,68 …… Bearing.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiaki Ito 1-1 Showa-cho, Kariya city, Aichi Japan Denso Co., Ltd. (72) Inventor Taizo Abe 1-1-1 Showa-cho, Kariya city, Aichi Nippon Denso Co., Ltd. (72) Inventor Susumu Hashimoto 390 Umeda, Kosai City, Shizuoka Prefecture Asmo Co., Ltd. (72) Inventor Kazuyuki Hashimoto 390 Umeda, Kosai City, Shizuoka Prefecture Asmo Co., Ltd. (56) References , U)

Claims (1)

(57) [Claims] 1. A pump housing provided with a pump section for pumping a fluid, an output shaft provided with a pump driver for driving the pump section at one end side, and a pump housing fixed to the pump housing. An electric pump comprising: a motor section provided on the other end side of the output shaft, wherein the pump section drives the output shaft by the motor section to pump fluid through the pump housing. An electric pump having two bearings that rotatably support one end side of the output shaft and does not support the other end side of the output shaft by a bearing.