CN110537021B

CN110537021B - Vane pump

Info

Publication number: CN110537021B
Application number: CN201880026175.6A
Authority: CN
Inventors: 下口保; 大后富男
Original assignee: Fujiko Corp
Current assignee: Fujiko Corp
Priority date: 2017-04-22
Filing date: 2018-04-17
Publication date: 2021-04-30
Anticipated expiration: 2038-04-17
Also published as: CN110537021A; WO2018194042A1; JP6773991B2; JPWO2018194042A1

Abstract

Provided is a vane pump which can discharge two types of pressure oil, namely high pressure oil and low pressure oil, and can be started quickly. The vane pump is provided with: a pump body (2) having a suction port (30); a stator (3); a rotor (4); a plurality of blades (6); a1 st side plate (7) which is arranged on one end surface side of the stator (3) and on which oil is discharged; a2 nd side plate (8) which is arranged on the other end surface side of the stator (3) and on which oil is sucked; and a pump cover (10) having two oil discharge ports (40, 41) and joined to the pump body (2), wherein a pair of back pressure grooves (70, 71, 80, 81) are formed on the rotor (4) side of the 1 st and 2 nd side plates (7, 8), and the back pressure groove (70) is provided with a1 st back pressure groove (70A), a2 nd back pressure groove (70B) having a shorter groove length than the 1 st back pressure groove, and a3 rd back pressure groove (70C) having the narrowest groove width and connecting the two back pressure grooves (70A, 70B).

Description

Vane pump

Technical Field

The present invention relates to a balanced vane pump for controlling a clutch of an automatic transmission mounted in an automobile or an industrial vehicle by controlling inflow and outflow of oil.

Background

Conventionally, in a vane pump used in an automatic transmission of an automobile, a vane positioned above a rotating shaft (rotor) when an engine is stopped is accommodated in a vane groove on the outer periphery of the rotor due to its own weight.

Further, the vane located below the rotor extends downward from the vane groove and contacts the stator located on the outer periphery of the vane.

Therefore, when the rotor starts to rotate (when the vane pump is started), it takes a certain time until the vanes once accommodated in the vane grooves are again protruded from the rotor after the vanes are accommodated in the vane grooves again in association with the rotation of the rotor.

As a result, the vane pump does not function as a pump (does not generate pressure) until the vanes project toward the outer periphery of the rotor, and therefore, the start-up of the vane pump is delayed.

Also, in the case where the ambient temperature is relatively warm, the viscosity of the oil is relatively low, and therefore, even if the rotor starts to rotate, the blades are relatively easily protruded from the rotor.

However, in a low-temperature environment such as winter, the viscosity of the oil increases, and the viscous resistance between the vane and the oil also increases, so that the protrusion of the vane from the rotor is slowed as a result, and it takes time until a desired pressure is generated as compared with the case of a warm environment.

Therefore, patent document 1 discloses the following: the plurality of back pressure grooves are provided on the end surface of the side plate constituting the vane pump, and the plurality of back pressure grooves are connected to each other by the communication groove, whereby the vane dropped into the vane groove of the rotor at the time of starting the pump is rapidly protruded, whereby the startability of the pump can be improved.

Patent document 1: japanese laid-open patent publication No. 2012 and 092654

Disclosure of Invention

Problems to be solved by the invention

In the vane pump disclosed in patent document 1, since all the back pressure grooves provided in the end surface of the side plate are connected by the communication groove, even if a plurality of discharge ports are provided in the interior, if the discharge port of the vane pump is only one, the discharge pressure of the vane pump is finally at a single level.

However, when the vane pump is applied to a transmission for an automobile, pressure oil of both high pressure and low pressure (two levels) is required.

In this case, in the vane pump disclosed in patent document 1, since the discharge pressure is one level, another device such as a distribution valve for dividing the oil pressure into two levels of high pressure and low pressure is further required.

Accordingly, an object of the present invention is to provide a vane pump which can discharge two types of pressure oil, high pressure and low pressure, by using only 1 vane pump and can be started up quickly.

Means for solving the problems

In order to solve the above problem, the present invention is a vane pump including at least: a pump body having a suction port; a stator accommodated in the recess of the pump body; a rotor housed in the stator and having a plurality of blade grooves radially formed on an outer circumferential surface thereof; a plurality of vanes fitted into the plurality of vane grooves; a1 st side plate disposed on one end surface side of the stator and on an oil discharge port side; a2 nd side plate disposed on the other end surface side of the stator and on the oil suction port side; and a pump cover having two oil discharge ports and covering an opening portion of the recess of the pump body, wherein a pair of independent back pressure grooves are formed on the rotor side of the 1 st side plate and the 2 nd side plate.

Here, the plurality of blades are attached so as to be able to enter and exit toward the stator in a state of being fitted into the blade grooves, respectively.

And, this backpressure groove has: 1 st back pressure groove; the 2 nd back pressure groove is shorter than the 1 st back pressure groove in length; and a3 rd back pressure groove connecting the 1 st back pressure groove and the 2 nd back pressure groove, and having a groove width narrower than the 1 st back pressure groove and the 2 nd back pressure groove.

Further, the 2 nd back pressure groove of the 1 st side plate is provided with a hole portion penetrating from the rotor side of the 1 st side plate to the opposite (reverse) side of the rotor.

The 2 nd back pressure groove of the 1 st side plate may be connected to a high pressure chamber formed by a concave portion provided in the pump cover and the 1 st side plate via the hole portion.

Further, the groove depth of the 1 st back pressure groove may be made deeper as approaching the 3 rd back pressure groove.

Effects of the invention

According to the vane pump of the present invention, it is possible to discharge both high-pressure and low-pressure oil in a single body without additional hydraulic equipment such as a distribution valve.

Further, the effect is exhibited that the vane pump can be started quickly even in an environment of extremely low temperature (-30 ℃ C. or lower) where the viscosity of oil is the lowest.

Drawings

Fig. 1 is a sectional view showing a vane pump 1 according to an embodiment of the present invention.

Fig. 2 is an X-X sectional view of the vane pump 1 in fig. 1.

Fig. 3 is a Y-Y sectional view of the vane pump 1 in fig. 1.

Fig. 4 is a plan view of the 1 st side plate 7 shown in fig. 1 on the rotor 4 side.

Fig. 5 is a plan view of the side of the 1 st side plate 7 shown in fig. 1 opposite to the rotor 4.

Fig. 6 is an enlarged view of the back pressure groove 70 of the 1 st side plate 7 shown in fig. 4.

Fig. 7 is a plan view of the 2 nd side plate 8 shown in fig. 1 on the rotor 4 side.

Fig. 8 is a plan view of the side of the 2 nd side plate 8 shown in fig. 1, which is opposite to the rotor 4.

Fig. 9 is an enlarged view of the back pressure groove 80 of the 2 nd side plate 8 shown in fig. 7.

Fig. 10 is a schematic diagram showing the overall configuration of a performance testing apparatus 200 used in the examples.

FIG. 11 is a graph showing the results of a performance test using the product of the present invention in examples.

Fig. 12 is a graph showing the results of a performance test using a conventional product in the example.

Description of the reference numerals

1. 201 vane pump

2 Pump body

3 stator

4 rotor

5 blade groove

6 blade

7 the 1 st side plate

8 nd 2 nd side plate

9 shaft

10 pump cover

20 pump body recess

30 suction inlet

40. 41 discharge port

50. Hole part of 51 st side plate 1

60. 61 high pressure chamber

70. 71 back pressure groove of 1 st side plate

No. 1 back pressure groove of No. 1

side plate

70A, 71A

No. 2 back pressure groove of No. 1 side plate of 70B, 71B

No. 3 back pressure groove of 70C, 71C No. 1 side plate

72 1 st suction port of 1 st side plate

73 No. 2 suction port of No. 1 side plate

76 No. 1 discharge port of No. 1 side plate

77 No. 2 ejection port of No. 1 side plate

80. Back pressure groove of 81 nd 2 nd side plate

No. 1 back pressure groove of No. 2 side plates of 80A and 81A

No. 2 back pressure groove of No. 2 side plates of 80B and 81B

No. 3 back pressure groove of No. 2 side plates of 80C, 81C

82 st suction port of 2 nd side plate

83 2 nd suction port of 2 nd side plate

86 No. 1 storage groove of No. 2 side plate

87 nd side plate 2 nd storage groove

100. 101 pump cover recess

200 performance test device

210 oil pan

220 motor

230 revolution meter

240 pressure valve

250 pressure transducer

261-264 oil circuit

270 thermostatic chamber

The groove length of the 1 st to 3 rd back pressure grooves of the 1 st side plate of la to lc

Groove length of 1 st to 3 rd back pressure grooves of fa-fc 2 nd side plate

Imaginary center of O1 side 1 plate

Imaginary center of O2 side plate 2

Detailed Description

An example of an embodiment of the present invention will be described with reference to the drawings.

Fig. 1 is a sectional view of a vane pump 1 as an example of an embodiment of the present invention, fig. 2 is an X-X sectional view of the vane pump 1 in fig. 1, and fig. 3 is a Y-Y sectional view of the vane pump 1 in fig. 1.

As shown in fig. 1 to 3, the vane pump 1 is roughly composed of a pump body 2 and a pump cover 10.

The oil is sucked into the vane pump 1 from a suction port 30 provided at one portion of the pump body 2, and the oil in the vane pump 1 is discharged (discharged) from

discharge ports

40 and 41 provided at two portions of the pump cover 10.

As shown in fig. 1, the vane pump 1 is attached with a shaft 9 so as to penetrate a hole in the center of the rotor 4 and a hole in the center of the pump cover 10.

As shown in fig. 2 and 3, the annular stator 3 is housed inside the pump body 2 (the concave portion 20) in a nested manner, and the rotor 4 is housed inside the stator 3 in a nested manner.

A plurality of

vane grooves

5, 5 are radially provided on the outer peripheral surface of the rotor 4, and a plurality of

vanes

6, 6 are fitted into the

respective vane grooves

5, 5 so as to be able to move in and out in the radial direction of the rotor 4.

Each of the vanes 6 moves rotationally while moving in and out of the stator 3 along the inside thereof in accordance with the rotation of the rotor 4.

As shown in fig. 1, a1 st side plate 7 and a2 nd side plate 8 having a substantially circular disk shape are disposed on both end surfaces of the stator 3 so as to sandwich the rotor 4 from both sides.

As shown in fig. 1 to 3, the 1 st side plate 7 is disposed on one end surface side of the stator 3 and the rotor 4 and at a position close to the

discharge ports

40 and 41, and the 2 nd side plate 8 is disposed on the other end surface side of the stator 3 and the rotor 4 and at a position close to the suction port 30.

As shown in fig. 1, the space defined by the

concave portions

100 and 101 of the pump cover 10 and the 1 st side plate 7 is referred to as a high-

pressure chamber

60 and 61.

The oil flowing from the suction port 30 into the vane pump 1 is pressurized by the high-

pressure chambers

60 and 61 and is delivered in the direction of the

discharge ports

40 and 41.

Next, a mode of the 1 st side plate 7 will be described with reference to the drawings.

Fig. 4 is a plan view of the 1 st side plate 7 shown in fig. 1 viewed from the rotor 4 side, and fig. 5 is a plan view of the 1 st side plate 7 shown in fig. 1 viewed from the side (pump cover 10 side) opposite to the rotor 4.

As shown in fig. 4, a1 st suction port 72 and a2 nd suction port 73 are formed in an end surface of the 1 st side plate 7 disposed on the rotor 4 side, and the 1 st suction port 72 and the 2 nd suction port 73 feed oil in the direction of the rotor 4 after the oil is sucked into the vane pump 1 through the suction port 30 shown in fig. 1.

Further, the 1 st discharge port 76 and the 2 nd discharge port 77 for conveying the oil flowing out of the rotor 4 in the directions of the two

discharge ports

40 and 41 are also formed in the end surface of the 1 st side plate 7 disposed on the rotor 4 side.

As shown in fig. 4, a pair of

back pressure grooves

70 and 71 are provided in an arc shape so as to face each other around a central hole portion through which the shaft 9 passes, on the end surface of the 1 st side plate 7 disposed on the rotor 4 side.

The

back pressure grooves

70 and 71 are formed substantially by the 1 st back

pressure grooves

70A and 71A, the 2 nd back

pressure grooves

70B and 71B, and the 3 rd back

pressure grooves

70C and 71C.

Fig. 6 shows an enlarged view of the back pressure groove 70 provided in the end surface of the 1 st side plate 7.

As shown in fig. 6, the groove length la of the 1 st back pressure groove 70A is longest among the 1 st to 3 rd back pressure grooves 70A to 70C provided in the 1 st side plate 7.

In addition, the groove depth (distance from the surface of the 1 st side plate 7 to the groove bottom) of the 1 st back pressure groove 70A gradually becomes deeper as it approaches the 3 rd back pressure groove 70C.

As shown in fig. 4 and 6, the 2 nd back pressure groove 70B is a back pressure groove connected to the 1 st back pressure groove 70A via a3 rd back pressure groove 70C described later.

As shown in fig. 6, the groove length lb of the 2 nd back pressure groove 70B is shorter than the groove length la of the 1 st back pressure groove 70A.

The 2 nd back pressure groove 70B includes a hole portion 50 that connects both surfaces (the rotor 4 side and the pump cover 10 side) of the 1 st side plate 7.

As shown in fig. 4 and 6, the 3 rd back pressure groove 70C is a back pressure groove connecting the 1 st back pressure groove 70A and the 2 nd back pressure groove 70B.

The groove length lc of the 3 rd back pressure groove 70C is shortest among the 1 st to 3 rd back pressure grooves 70A to 70C.

The groove width of the 3 rd back pressure groove 70C is the narrowest among the 1 st to 3 rd back pressure grooves 70A to 70C.

Here, the 3 rd back pressure groove 70C is a back pressure groove for throttling the flow of the oil when the oil moves from the 1 st back pressure groove 70A to the 2 nd back pressure groove 70B.

As one of the modes, the groove width of the 3 rd back pressure groove 70C is made narrower than the other back pressure grooves.

Therefore, other forms may be used as long as the flow rate can be temporarily throttled.

In the present application, as shown in fig. 6, the groove lengths la to lc of the 1 st to 3 rd back pressure grooves 70A to 70C are lengths (arc lengths) of arcs formed by connecting the virtual center O1 of the 1 st side plate 7 and both end portions of the back pressure grooves 70A to 70C.

The above description relates to the structure of the back pressure groove 70, but the arrangement relationship, the groove length, and the like of the 1 st back pressure groove 71A, the 2 nd back pressure groove 71B, and the 3 rd back pressure groove 71C forming the other back pressure groove 71 are also the same.

As shown in fig. 5, the above-described 1

st discharge port

76 and 2 nd discharge port 77 are formed in the end surface of the 1 st side plate 7 disposed on the pump cover 10 side.

That is, the 1 st discharge port 76 and the 2 nd discharge port 77 are provided in the 1 st side plate 7 so as to penetrate both surfaces (the rotor 4 side and the pump cover 10 side) of the 1 st side plate 7, similarly to the above-described

holes

50 and 51.

Next, a mode of the 2 nd side plate 8 will be described with reference to the drawings.

Fig. 7 is a plan view of the 2 nd side plate 8 shown in fig. 1 viewed from the rotor 4 side, and fig. 8 is a plan view of the 2 nd side plate 8 shown in fig. 1 viewed from the side opposite to the rotor 4 (the suction port 30 side).

First, after oil is sucked into the vane pump 1 through the suction port 30 shown in fig. 1, the 1 st suction port 82 and the 2 nd suction port 83 which feed the oil in the direction of the rotor 4 are provided in the 2 nd side plate 8 as shown in fig. 7 and 8.

As shown in fig. 7, a1 st storage groove 86 and a2 nd storage groove 87 for storing a certain amount of oil inside the vane pump 1 are formed in the end surface of the 2 nd side plate 8 disposed on the rotor 4 side.

As shown in fig. 7, a pair of

back pressure grooves

80, 81 are provided in an arc shape so as to face each other around a central hole portion through which the shaft 9 passes, on an end surface of the 2 nd side plate 8 disposed on the rotor 4 side.

The

back pressure grooves

80 and 81 are formed by 1 st back

pressure grooves

80A and 81A, 2 nd back

pressure grooves

80B and 81B, and 3 rd back

pressure grooves

80C and 81C, respectively. Fig. 9 is an enlarged view of the back pressure groove 80 of the 2 nd side plate 8 shown in fig. 7.

As shown in fig. 9, the groove length fa of the 1 st back pressure groove 80A is longest among the 1 st to 3 rd back pressure grooves 80A to 80C provided in the 2 nd side plate 8.

In addition, the groove depth (distance from the surface of the 2 nd side plate 8 to the groove bottom) of the 1 st back pressure groove 80A gradually becomes deeper as it approaches the 3 rd back pressure groove 80C.

As shown in fig. 7 and 9, the 2 nd back pressure groove 80B is a back pressure groove connected to the 1 st back pressure groove 80A via a3 rd back pressure groove 80C described later.

The groove length fb of the 2 nd back pressure groove 80B is shorter than the groove length fa of the 1 st back pressure groove 80A.

As shown in fig. 7 and 9, the 3 rd back pressure groove 80C is a back pressure groove connecting the 1 st back pressure groove 80A and the 2 nd back pressure groove 80B described above.

The groove length fc of the 3 rd back pressure groove 80C is shortest among the 1 st to 3 rd back pressure grooves 80A to 80C.

The groove width of the 3 rd back pressure groove 80C is the narrowest among the 1 st to 3 rd back pressure grooves 80A to 80C.

Here, as shown in fig. 9, the groove lengths fa to fc of the 1 st to 3 rd back pressure grooves 80A to 80C are lengths (arc lengths) of arcs formed by connecting the virtual center O2 of the 2 nd side plate 8 and both end portions of the back pressure grooves 80A to 80C.

The above description relates to the configuration of the back pressure groove 80, but the arrangement relationship, the groove length, and the like of the 1 st back pressure groove 81A, the 2 nd back pressure groove 81B, and the 3 rd back pressure groove 81C forming the other back pressure groove 81 are also the same.

The operation of the vane pump according to the present invention will be described with reference to the above embodiments.

The vane pump 1 of the present invention rotates the rotor 4 by rotating the shaft 9 shown in fig. 2 and 3, and the plurality of

vanes

6, 6 rotate while moving in and out along the vane grooves 5, respectively, thereby sucking oil from the suction port 30 and discharging oil from the

discharge ports

40, 41.

The oil sucked into the vane pump 1 from the suction port 30 enters the periphery of the rotor 4 and the vanes 6 through the 1 st and 2

nd suction ports

72 and 73 of the 1 st side plate 7, the 1 st and 2

nd suction ports

82 and 83 of the 2 nd side plate 8, and the like.

When oil entering the plurality of

vane grooves

5 and 5 provided on the outer periphery of the rotor 4 moves from the 2 nd side plate 8 side to the 1 st side plate 7 side, the oil also enters the rotor 4 side.

That is, the movement of the oil from the vane groove 5 to the rotor 4 side acts in a direction in which the vane 6 projects outward of the rotor 4.

On the other hand, when the rotation of the shaft 9 is further advanced, the blades 6 are accommodated in the blade grooves 5 of the rotor 4 along the shape of the inner circumferential surface of the stator 3.

At this time, the oil present around the rotor 4 also enters the vane grooves 5 of the rotor 4.

The oil that has entered the vane grooves 5 is collected in the back pressure grooves of the two side plates (the 1 st side plate 7 and the 2 nd side plate 8) disposed on both sides of the rotor 4.

For example, the oil collected in the back pressure groove 70 of the 1 st side plate 7 is first collected in the 1 st back pressure groove 70A.

Here, when the rotation of the shaft 9 is counterclockwise in the paper surface of fig. 2, the plurality of

vanes

6 and 6 are accommodated in the vane grooves 5 of the rotor 4, and therefore, the oil located in the 1 st back pressure groove 70A moves in the direction of the 2 nd back pressure groove 70B by the pressure thereof.

The oil in the 1 st back pressure groove 70A passes through the 3 rd back pressure groove 70C having the narrowest groove width before moving to the 2 nd back pressure groove 70B.

Therefore, the movement of the oil collected in the 1 st back pressure groove 70A is temporarily throttled by the 3 rd back pressure groove 70C before moving in the direction of the 2 nd back pressure groove 70B.

As a result, most of the oil collected in the 1 st back pressure groove 70A moves in the direction of the vane grooves 5 of the rotor 4, and only the remaining oil that has not moved to the vane grooves 5 moves to the 2 nd back pressure groove 70B through the 3 rd back pressure groove 70C.

The oil in the other 1 st back pressure groove 71A also moves in the same direction to the vane groove 5 and the 2 nd back pressure groove 71B.

The same applies to the movement of oil collected in the

back pressure grooves

80 and 81 of the 2 nd side plate 8.

As described above, since most of the oil collected in the 1 st back

pressure grooves

70A and 71A of the 1 st side plate 7 and the 1 st back

pressure grooves

80A and 81A of the 2 nd side plate 8 moves toward the vane grooves 5 of the rotor 4, the pressure of the oil moving from the 1 st back

pressure grooves

70A, 71A, 80A, and 81A toward the vane grooves 5 becomes higher than the pressure of the oil entering from the periphery of the rotor 4 toward the vane grooves 5, and the vanes 6 can be easily extended from the vane grooves 5 in the outer diameter direction.

Therefore, with the above-described configuration of the back pressure groove provided on the side plate constituting the vane pump of the present invention, the projection of the vane from the vane groove can be easily performed.

As a result, the hydraulic pressure can be generated quickly when the vane pump is started.

As shown in fig. 4 to 9, the vane pump of the present invention is provided with back pressure grooves provided in the two side plates, respectively.

In particular, as described above, the

holes

50 and 51 connected from the rotor 4 side to the side opposite to the rotor 4 (the pump cover 10 side) are provided in the 2 nd back

pressure grooves

70B and 71B of the 1 st side plate 7 provided on the

ejection port

40 and 41 sides of the two locations, respectively.

These

holes

50 and 51 are connected to high-

pressure chambers

60 and 61 formed between the 1 st side plate 7 and the pump cover 10, and these high-

pressure chambers

60 and 61 are connected to two

discharge ports

40 and 41, respectively.

That is, the oil in the 2 nd back

pressure grooves

70B, 71B of the 1 st side plate 7 is discharged from the two

discharge ports

40, 41 through the

respective holes

50, 51 and the

high pressure chambers

60, 61.

As described above, in the vane pump of the present invention, the back pressure grooves provided in the side plate are formed as a pair of independent grooves, and the oil passages from the back pressure grooves to the discharge ports are also provided separately.

Thus, two kinds of pressure oil, high pressure and low pressure, can be supplied by 1 vane pump.

Example 1

The performance test of the vane pump in this embodiment will be described with reference to the drawings.

The performance test was conducted for the purpose of confirming the starting performance of the vane pump in an extremely low temperature (-30 ℃) environment using the vane pump of the present invention (hereinafter referred to as "the present invention product") and a conventional vane pump (hereinafter referred to as "the conventional product").

Fig. 10 shows the overall configuration of a performance testing apparatus 200 used for the performance test.

First, the vane pump of the present invention was used for the performance test in the manner shown in fig. 1 to 9.

In contrast, the conventional product uses the (1 st and 2 nd) side plates having the 1 st back

pressure grooves

70A, 71A, 80A, 81A and the 2 nd back

pressure grooves

70B, 71B, 80B, 81B integrated with each other without providing the 3 rd back

pressure grooves

70C, 71C, 80C, 81C of the 1 st side plate 7 shown in fig. 4 and the 2 nd back pressure grooves 8 shown in fig. 7.

The other constituent elements are the same as those of the present invention.

Next, the performance testing apparatus 200 is constituted by the motor 220, the pressure valve 240, and the like in addition to the vane pump 201, and these mechanical components are connected to each other through oil passages 261 to 264.

By the rotation of the shaft of the motor 220, the oil in the oil pan 210 is sucked into the vane pump 201 through the oil passage 261.

The rotation speed of the shaft of the motor 220 can be measured by a rotation meter 230 provided to the shaft.

The oil sucked into the vane pump 201 is discharged from the

discharge ports

40 and 41 shown in fig. 2, and is sent to the pressure valve 240 through the

oil passages

262 and 263.

The pressure (oil pressure) of the oil in the performance testing apparatus 200 is adjusted by the degree of opening and closing of the pressure valve 240.

The oil flowing out of the pressure valve 240 finally returns to the oil pan 210 via an oil passage 264.

As shown in fig. 10, the entire set of mechanical components such as the vane pump 201, the motor 220, and the pressure valve 240 are all housed in the thermostatic chamber 270, and the test environment (test temperature) can be freely adjusted.

The performance testing apparatus 200 is also provided with a power supply for the motor 220, electric wiring lines for controlling the rotation meter 230 and the pressure transducer 250, various measuring devices for measuring the rotation speed of the motor 220 and the oil pressures of the oil passages 261 to 264, and the like, which are not shown.

Next, a test method for the performance test will be described.

The motor 220 was rotated in a state where the temperature in the thermostatic chamber 270 of the performance test apparatus 200 shown in fig. 10 was set to 25 ℃, and oil was supplied to the vane pump 201.

At the same time, the pressure (discharge pressure) of the oil from the vane pump 201 is set to 1.8MPa by the pressure valve 240.

After a predetermined time has elapsed in this state, the motor 220 is stopped, and the supply of oil to the vane pump 201 is stopped.

Then, the temperature in the thermostatic chamber 270 was changed to-30 ℃ and the whole set of mechanical components such as the vane pump 201 was maintained in this state for 8 hours.

After 8 hours have elapsed since the temperature in thermostatic chamber 270 reached-30 ℃, motor 220 was started at 200rpm and held for 1.5 seconds.

Thereafter, the rotation speed of the motor 220 is changed from 200rpm to 1800 rpm.

In the performance test, the change in pressure (discharge pressure) of the oil discharged from the vane pump 201 within about 12 seconds from the start of the motor 220 at 200rpm was measured over time using the pressure transducer 250 and a measuring device (not shown).

Hereinafter, the results of performance tests of the vane pumps using the product of the present invention and the conventional product will be described with reference to the drawings.

Fig. 11 shows the results (graph) of the performance test using the product of the present invention, and fig. 12 shows the results (graph) of the performance test using the conventional product.

In both fig. 11 and 12, the horizontal axis of the graph showing the test results indicates the elapsed time (unit: seconds) from the start of the motor 220 at a rotation speed of 200rpm, the right vertical axis indicates the rotation speed (unit: rpm) of the motor 220 measured by the tachometer 230 shown in fig. 10, and the left vertical axis indicates the pressure (unit: MPa) of the oil discharged from the vane pump 201 measured by the pressure converter 250 shown in fig. 10.

The horizontal axis of the two figures shows the time at which the motor starts to start (0 second) as a starting point.

In the graphs of fig. 11 and 12, the time period from when the motor is started and the rotation speed reaches 200rpm to when 1.5 seconds elapses is divided into a1 and B1, the time until the oil is confirmed to be ejected from the vane pump is divided into a2 and B2, and the time until the oil pressure reaches the maximum value (maximum pressure) is divided into A3 and B3.

In the performance test using the product of the present invention, first, as a preparatory operation, as shown in fig. 11, the motor was started, and after about 0.5 second, the rotation speed reached 200rpm, and the state was maintained for 1.5 seconds (interval a1 shown in fig. 11).

Thereafter, the rotation speed of the motor was changed from 200rpm to 1800 rpm.

When the rotation speed of the motor was changed to 1800rpm, the vane pump of the present invention confirmed that: at the moment (after 0.046 seconds: interval a2 shown in fig. 11), the oil pressure rises (the pressure of the oil rises).

After about 0.6 seconds from the oil pressure increase by the vane pump, it was confirmed that: the oil pressure reached a maximum (about 4.2MPa) (interval a3 shown in fig. 11), after which the oil pressure dropped to about 1.7MPa and maintained that pressure.

In contrast, in the performance test using the conventional product, as in the case of the performance test using the product of the present invention, as shown in fig. 12, after the motor was held for 1.5 seconds from when the rotation speed of the motor reached 200rpm (B1 interval shown in fig. 12), the rotation speed of the motor was changed from 200rpm to 1800 rpm.

When the rotation speed of the motor was changed to 1800rpm, it was confirmed from the conventional product that: after about 4.6 seconds from the change of the rotation speed of the motor (B2 interval shown in fig. 12), the oil pressure rises.

After confirming that the oil pressure by the vane pump reached the maximum value (about 5MPa) after about 0.2 seconds from the rise of the oil pressure (B3 interval shown in fig. 12), the oil pressure was reduced to about 1.7MPa and maintained as in the performance test results of the product of the present invention.

Based on the above test results, the starting performance of the vane pump in an extremely low temperature (-30 ℃) use environment was compared, and in the conventional vane pump (conventional product), it took about 4.6 seconds from the time when the oil was supplied by the rotation of the motor to the time when the oil discharge was started (until the vane pump was started).

On the other hand, in the vane pump of the present invention, it was confirmed that: the oil is instantaneously discharged to the outside of the vane pump from the time of receiving the supply of the oil through the suction port, that is, the vane pump is instantaneously started as the rotation speed of the motor increases.

Industrial applicability

The vane pump of the present invention can control a plurality of discharge pressures, and is excellent in startability, and therefore can be used for various vane pumps.

Claims

1. A vane pump at least comprises: a pump body having a suction port; a stator housed in the recess of the pump body; a rotor housed in the stator and having a plurality of blade grooves radially formed on an outer circumferential surface thereof; a plurality of vanes fitted into the plurality of vane grooves; a1 st side plate disposed on one end surface side of the stator and on an outlet port side; a2 nd side plate disposed on the other end surface side of the stator and on the side of the suction port; and a pump cover having the ejection ports at two locations and covering an opening portion of the recess of the pump body,

a pair of independent back pressure grooves are formed on the side of the 1 st side plate and the 2 nd side plate where the rotor is located,

the back pressure groove has:

1 st back pressure groove;

the 2 nd back pressure groove, the groove length is shorter than said 1 st back pressure groove; and

a3 rd back pressure groove connecting the 1 st back pressure groove and the 2 nd back pressure groove and having a groove width narrower than the 1 st back pressure groove and the 2 nd back pressure groove,

the 2 nd back pressure groove of the 1 st side plate has a hole portion penetrating from the side of the 1 st side plate where the rotor is located to the opposite side of the rotor,

the 2 nd back pressure groove of the 1 st side plate is connected to a high pressure chamber formed by a concave portion provided in the pump cover and the 1 st side plate via the hole portion.

2. Vane pump according to claim 1,

the groove depth of the 1 st back pressure groove becomes deeper as approaching the 3 rd back pressure groove.