WO2018194042A1

WO2018194042A1 - Vane pump

Info

Publication number: WO2018194042A1
Application number: PCT/JP2018/015787
Authority: WO
Inventors: 保下口; 富男大后
Original assignee: 株式会社不二越
Priority date: 2017-04-22
Filing date: 2018-04-17
Publication date: 2018-10-25
Also published as: CN110537021A; JPWO2018194042A1; JP6773991B2; CN110537021B

Abstract

Provided is a vane pump capable of ejecting two types of pressure oil of high pressure and low pressure and performing a quick start. The vane pump is provided with: a pump body (2) including a suction inlet (30); a cam ring (3); a rotor (4); a plurality of vanes (6); a first side plate (7) disposed on an oil ejection side which is on one end surface side of the cam ring (3); a second side plate (8) disposed on an oil suction side which is on an another end surface side of the cam ring (3); and a pump cover (10) which includes oil ejection openings (40, 41) at two locations and which is joined to the pump body (2). A pair of back pressure grooves (70, 71, 80, 81) are formed on the rotor (4) side of the first and second side plates (7, 8). The back pressure groove (70) is provided with a first back pressure groove (70A), a second back pressure groove (70B) having a shorter groove length, and a third back pressure groove (70C) connecting the two back pressure grooves (70A, 70B) and having the smallest groove width.

Description

Vane pump

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

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

Further, the vane positioned below the rotor protrudes downward from the vane groove and is in contact with the cam ring on the outer periphery of the vane.
For this reason, when the rotor starts rotating (when the vane pump starts), the vane is accommodated in the vane groove again as the rotor rotates, and then the vane once stored in the vane groove is fixed until the vane jumps out of the rotor again. It takes time.
As a result, since the vane does not act as a pump (no pressure is generated) until it jumps out of the rotor, the start of the vane pump is delayed.

Furthermore, when the ambient temperature is relatively warm, the viscosity of the oil is relatively low, so that the vane is relatively easy to jump out of the rotor even if the rotor starts rotating.
However, in a low temperature atmosphere such as in winter, the viscosity of the oil increases and the viscosity resistance between the vane and the oil also increases. As a result, the vane jumps out of the rotor, which is slower than in a warm atmosphere. It takes time to generate pressure.

Therefore, in Patent Document 1, a 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 a communication groove, so that the pump falls into the vane groove of the rotor when the pump is started. It is disclosed that the startability of the pump can be improved by allowing the vane that has come out to jump out quickly.

Japanese Laid-Open Patent Publication No. 2012-092654

In the vane pump disclosed in Patent Document 1, since all the back pressure grooves provided on the end surface of the side plate are connected by communication grooves, even if there are a plurality of discharge ports inside, the discharge port of the vane pump is 1 If it is only a place, the discharge pressure as a vane pump will finally be 1 level.

However, when the vane pump is applied to an automotive transmission, two types (two levels) of high pressure and low pressure oil are required.
In this case, since the vane pump disclosed in Patent Document 1 has a discharge pressure of one level, a separate device such as a distribution valve that divides the oil pressure into two levels of high pressure and low pressure is further required.

Therefore, an object of the present invention is to provide a vane pump that discharges two types of high-pressure and low-pressure oil with only one vane pump, and quickly starts the vane pump.

In order to solve the problems described above, the present invention includes at least a pump body having an oil suction port, a cam ring accommodated in a recess of the pump body, and a plurality of vanes on the outer peripheral surface accommodated in the cam ring. A rotor having grooves formed radially, a plurality of vanes fitted in the plurality of vane grooves, a first side plate disposed on one end face side of the cam ring and on the oil discharge port side, and the cam ring In a vane pump comprising: a second side plate disposed on the oil suction port side on the other end surface side; and a pump cover having two oil discharge ports and covering an opening portion of a recess of the pump body. A pair of independent back pressure grooves are formed on the rotor side of the first and second side plates.
Here, the plurality of vanes are attached so as to be able to go in and out toward the cam ring while being fitted in the vane grooves.

And the back pressure groove connects the first back pressure groove, the second back pressure groove whose groove length is shorter than the first back pressure groove, the first back pressure groove and the second back pressure groove, The third back pressure groove has a narrower width than the first back pressure groove and the second back pressure groove.

The second back pressure groove of the first side plate is provided with a hole penetrating from the rotor side of the first side plate to the opposite (reverse) side of the rotor.
The 2nd back pressure groove of the 1st side plate can also be constituted so that it may connect with the high pressure room formed from the crevice provided in the pump cover and the 1st side plate via this hole.
Further, the depth of the first back pressure groove may be increased as it approaches the third back pressure groove.

According to the vane pump of the present invention, two types of high-pressure and low-pressure oil can be discharged alone without the need for a separate hydraulic device such as a distribution valve.
In addition, there is an effect that the vane pump can be started quickly even in an extremely low temperature (−30 ° C. or lower) atmosphere where the viscosity of the oil is the lowest.

It is sectional drawing of the vane pump 1 which shows one Embodiment of this invention. FIG. 2 is a cross-sectional view of the vane pump 1 in FIG. 1 taken along line XX. FIG. 2 is a cross-sectional view of the vane pump 1 in FIG. 1 taken along line YY. It is a top view by the side of the rotor 4 of the 1st side plate 7 shown in FIG. It is a top view by the side of the non-rotor 4 of the 1st side plate 7 shown in FIG. It is an enlarged view of the back pressure groove 70 of the 1st side plate 7 shown in FIG. It is a top view by the side of the rotor 4 of the 2nd side plate 8 shown in FIG. FIG. 4 is a plan view of the second side plate 8 shown in FIG. 1 on the side opposite to the rotor 4. FIG. 8 is an enlarged view of a back pressure groove 80 of the second side plate 8 shown in FIG. 7. It is a schematic diagram which shows the whole structure of the performance test apparatus 200 used in the Example. It is a graph which shows the result of the performance test using this invention goods in the Example. It is a graph which shows the result of the performance test using the conventional product in the Example.

1,201 Vane pump 2 Pump body 3 Cam ring 4 Rotor 5 Vane groove 6 Vane 7 First side plate 8 Second side plate 9 Shaft 10 Pump cover 20 Recess 30 of pump

body Suction port

40, 41

Discharge port

50, 51 First

side Plate holes

60, 61

High pressure chambers

70, 71

Back pressure grooves

70A, 71A of the first side plate First

back pressure grooves

70B, 71B of the first side plate Second

back pressure grooves

70C, 71C of the first side plate First side plate third back pressure groove 72 First side plate first suction port 73 First side plate second suction port 76 First side plate first discharge port 77 First side plate second discharge port 80 81th Side plate

back pressure grooves

80A, 81A Second side plate first

back pressure grooves

80B, 81B Second side plate second

back pressure grooves

80C, 81C Second side plate third back pressure grooves 82 Second side plate The first suction port 83 of the second side plate The second suction port 86 of the second side plate The first storage groove 87 of the second side plate The

second storage groove

100, 101 of the second side plate The recess 200 of the pump cover Performance test apparatus 210 Oil pan 220 Motor 230 Tachometer 240 Pressure valve 250 Pressure transducers 261 to 264 Oil passage 270 Constant temperature chamber la to lc Groove lengths fa to fc of the first side plate of the first side plate First to third of the second side plate Groove length O1 of the third back pressure groove Virtual center O2 of the first side plate Virtual center of the second side plate

An example of an embodiment of the present invention will be described with reference to the drawings.
1 is a cross-sectional view of a vane pump 1 as an example of an embodiment of the present invention, FIG. 2 is a cross-sectional view of the vane pump 1 in FIG. 1 taken along line XX, and FIG. 3 is a cross-sectional view of the vane pump 1 in FIG. Respectively.

As shown in FIGS. 1 to 3, the vane pump 1 is roughly composed of a pump body 2 and a pump cover 10.
Oil is drawn into the vane pump 1 from one suction port 30 provided in the pump body 2, and the oil inside the vane pump 1 is discharged (discharged) from the two

discharge ports

40 and 41 provided in the pump cover 10. .
As shown in FIG. 1, the vane pump 1 is attached with a shaft 9 that penetrates through a central hole of the rotor 4 and a hole provided in the center of the pump cover 10.

As shown in FIGS. 2 and 3, the ring-shaped cam ring 3 and the rotor 4 are nested in the cam ring 3 inside the pump body 2.
A plurality of

vane grooves

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

vanes

6, 6 are fitted in the

respective vane grooves

5, 5 so that they can enter and exit in the radial direction of the rotor 4. It is.
As the rotor 4 rotates, each vane 6 rotates and moves along the inside of the cam ring 3 while entering and exiting the cam ring.

Moreover, as shown in FIG. 1, the substantially side-shaped 1st side plate 7 and the 2nd side plate 8 are arrange | positioned at the both end surfaces of the cam ring 3 in the form which pinches | interposes the rotor 4 from both sides.
As shown in FIGS. 1 to 3, the first side plate 7 is disposed on one end face side of the cam ring 3 and the rotor 4 and at a position near the

discharge ports

40 and 41, and on the other end face side of the cam ring 3 and the rotor 4. The second side plates 8 are arranged at positions close to the suction port 30.

Further, the space defined by the

recesses

100 and 101 of the pump cover 10 and the first side plate 7 is a space called

high pressure chambers

60 and 61 as shown in FIG.
Oil that has flowed into the vane pump 1 from the suction port 30 is sent in the direction of the

discharge ports

40 and 41 while being pressurized in the high-

pressure chambers

60 and 61.

Next, the form of the 1st side plate 7 is demonstrated using drawing.
4 is a plan view seen from the rotor 4 side of the first side plate 7 shown in FIG. 1, and FIG. 5 is a plan view seen from the side opposite to the rotor 4 (pump cover 10 side) of the first side plate 7 shown in FIG. Indicates.

As shown in FIG. 4, oil is sucked into the vane pump 1 into the end surface of the first side plate 7 disposed on the rotor 4 side through the suction port 30 shown in FIG. A first suction port 72 and a second suction port 73 are formed.
And the 1st discharge port 76 and the 2nd discharge port 77 which send the oil which came out of the rotor 4 to the direction of the two

discharge ports

40 and 41 are also formed in the end surface of the 1st side plate 7 arrange | positioned at the rotor 4 side. ing.

A pair of

back pressure grooves

70 and 71 are formed on the end surface of the first side plate 7 disposed on the rotor 4 side so as to face each other around a central hole through which the shaft 9 passes as shown in FIG. It is provided in an arc shape.
Each of the

back pressure grooves

70 and 71 is broadly formed by first

back pressure grooves

70A and 71A, second

back pressure grooves

70B and 71B, and third

back pressure grooves

70C and 71C.
An enlarged view of the back pressure groove 70 provided on the end face of the first side plate 7 is shown in FIG.

The groove length la of the first back pressure groove 70A is the longest among the first to third back pressure grooves 70A to 70C provided in the first side plate 7 as shown in FIG.
Further, the groove depth (the distance from the surface of the first side plate 7 to the groove bottom) of the first back pressure groove 70A gradually increases as it approaches the third back pressure groove 70C.

As shown in FIGS. 4 and 6, the second back pressure groove 70 B is a back pressure groove connected to the first back pressure groove 70 A via a third back pressure groove 70 C described later.
Further, the groove length lb of the second back pressure groove 70B is shorter than the groove length la of the first back pressure groove 70A as shown in FIG.
Furthermore, the second back pressure groove 70 B is provided with holes 50 that connect both surfaces (the rotor 4 side and the pump cover 10 side) of the first side plate 7.

As shown in FIGS. 4 and 6, the third back pressure groove 70C is a back pressure groove that connects the first back pressure groove 70A and the second back pressure groove 70B described above.
The groove length lc of the third back pressure groove 70C is the shortest among the first to third back pressure grooves 70A to 70C.
The groove width of the third back pressure groove 70C is the narrowest among the first to third back pressure grooves 70A to 70C.
Here, the third back pressure groove 70C is for narrowing the flow of oil when it moves from the first back pressure groove 70A to the second back pressure groove 70B.
As one of the means, the groove width of the third back pressure groove 70C is made narrower than others.
Therefore, other means may be used once the flow rate can be reduced.

In the present application, the groove lengths la to lc of the first to third back pressure grooves 70A to 70C are equal to the virtual center O1 of the first side plate 7 and both end portions of the back pressure grooves 70A to 70C as shown in FIG. It is assumed that the length of the arc formed by connecting (arc length).

The above description relates to the configuration of the back pressure groove 70. However, the arrangement of the first back pressure groove 71A, the second back pressure groove 71B, and the third back pressure groove 71C that form the other back pressure groove 71 is described. The same applies to the relationship and groove length.

As shown in FIG. 5, the first discharge port 76 and the second discharge port 77 described above are formed on the end surface of the first side plate 7 disposed on the pump cover 10 side.
That is, the 1st discharge port 76 and the 2nd discharge port 77 are the 1st side in the form which penetrates both surfaces (the rotor 4 side and the pump cover 10 side) of the 1st side plate 7 similarly to the above-mentioned

hole parts

50 and 51. It is provided on the plate 7.

Next, the form of the second side plate 8 will be described with reference to the drawings.
7 is a plan view seen from the rotor 4 side of the second side plate 8 shown in FIG. 1, and FIG. 8 is a plan view seen from the side opposite to the rotor 4 (the suction port 30 side) of the second side plate 8 shown in FIG. Respectively.

First, a first suction port 82 and a second suction port 83 that send oil in the direction of the rotor 4 after oil is sucked into the vane pump 1 through the suction port 30 shown in FIG. 1 are shown in FIGS. 7 and 8. In this way, the second side plate 8 is provided.
A first storage groove 86 and a second storage groove 87 for storing a certain amount of oil inside the vane pump 1 are formed on the end face of the second side plate 8 disposed on the rotor 4 side, as shown in FIG.

In addition, a pair of

back pressure grooves

80 and 81 are formed on the end surface of the second side plate 8 disposed on the rotor 4 side so as to face each other around the central hole through which the shaft 9 passes as shown in FIG. It is provided in an arc shape.
Each

back pressure groove

80, 81 is formed of a first

back pressure groove

80A, 81A, a second

back pressure groove

80B, 81B, and a third

back pressure groove

80C, 81C. An enlarged view of the back pressure groove 80 of the second side plate 8 shown in FIG. 7 is shown in FIG.

The groove length fa of the first back pressure groove 80A is the longest among the first to third back pressure grooves 80A to 80C provided in the second side plate 8 as shown in FIG.
Further, the groove depth (the distance from the surface of the second side plate 8 to the groove bottom) of the first back pressure groove 80A gradually increases as it approaches the third back pressure groove 80C.

The second back pressure groove 80B is a back pressure groove connected to the first back pressure groove 80A via a third back pressure groove 80C described later as shown in FIGS.
Further, the groove length fb of the second back pressure groove 80B is shorter than the groove length fa of the first back pressure groove 80A.

The third back pressure groove 80C is a back pressure groove that connects the first back pressure groove 80A and the second back pressure groove 80B described above as shown in FIGS.
The groove length fc of the third back pressure groove 80C is the shortest among the first to third back pressure grooves 80A to 80C.
The groove width of the third back pressure groove 80C is the narrowest among the first to third back pressure grooves 80A to 80C.

Here, the groove lengths fa to fc of the first to third back pressure grooves 80A to 80C are the virtual center O2 of the second side plate 8 and both ends of the back pressure grooves 80A to 80C as shown in FIG. It is assumed that the length of the arc formed by connecting (arc length).

Further, the above description relates to the configuration of the back pressure groove 80, but the arrangement relationship of the first back pressure groove 81A, the second back pressure groove 81B, and the third back pressure groove 81C that form the other back pressure groove 81. The same applies to the groove length and the like.

Based on the above embodiment, the effect | action of the vane pump of this invention is demonstrated using drawing.
In the vane pump 1 of the present invention, when the shaft 9 shown in FIGS. 2 and 3 rotates, the rotor 4 rotates, and the plurality of

vanes

6 and 6 rotate while moving in and out along the

vane grooves

5 and 5, respectively. Then, the oil is sucked from the suction port 30 and discharged from the

discharge ports

40 and 41.

The oil sucked into the vane pump 1 from the suction port 30 passes through the first and

second suction ports

72 and 73 of the first side plate 7 and the first and

second suction ports

82 and 83 of the second side plate 8. Then, it enters the periphery of the rotor 4 and the vane 6.

When the oil that has entered the plurality of

vane grooves

5 and 5 provided on the outer periphery of the rotor 4 moves from the second side plate 8 side to the first side plate 7 side, it also enters the rotor 4 side at the same time.
That is, the movement of the oil from the vane groove 5 to the rotor 4 side acts as an action in a direction in which the vane 6 jumps out of the rotor 4.

In contrast, when the rotation of the shaft 9 further proceeds, the vane 6 acts in the direction in which the vane 6 is accommodated in the vane groove 5 of the rotor 4 along the shape of the inner peripheral surface of the cam ring 3.
At this time, oil existing around the rotor 4 also enters the vane groove 5 of the rotor 4.
The oil that has entered the vane groove 5 is concentrated in the back pressure grooves of the two side plates (first side plate 7 and second side plate 8) disposed on both sides of the rotor 4.

For example, the oil concentrated in the back pressure groove 70 of the first side plate 7 first concentrates in the first back pressure groove 70A.
Here, when the rotation of the shaft 9 is counterclockwise on the paper surface of FIG. 2, the oil in the first back pressure groove 70 A is accommodated in the vane groove 5 of the rotor 4 because the plurality of

vanes

6 and 6 are accommodated in the rotor 4. The pressure moves toward the second back pressure groove 70B.

The oil in the first back pressure groove 70A passes through the third back pressure groove 70C having the narrowest groove width before moving to the second back pressure groove 70B.
Therefore, the movement of the oil concentrated in the first back pressure groove 70A is once narrowed by the third back pressure groove 70C before moving in the direction of the second back pressure groove 70B.
As a result, most of the oil concentrated in the first back pressure groove 70A moves in the direction of the vane groove 5 of the rotor 4, and only the remaining oil that has not moved to the vane groove 5 becomes the third back pressure groove 70C. Is moved to the second back pressure groove 70B.

The oil in the other first back pressure groove 71A also moves in the same manner toward the vane groove 5 and the second back pressure groove 71B.
The same applies to the movement of the oil concentrated in the

back pressure grooves

80 and 81 of the second side plate 8.

From the above, most of the oil concentrated in the first

back pressure grooves

70A, 71A of the first side plate 7 and the first

back pressure grooves

80A, 81A of the second side plate 8 is transferred to the vane grooves 5 of the rotor 4. Since it moves, the pressure of the oil moved from the first

back pressure grooves

70A, 71A, 80A, 81A to the vane groove 5 becomes higher than the pressure of the oil entering from the periphery of the rotor 4 into the vane groove 5, The vane 6 can be easily ejected from the vane groove 5 in the outer diameter direction.

Therefore, the vane can be easily ejected from the vane groove by the structure of the back pressure groove provided on the side plate constituting the vane pump of the present invention.
As a result, it is possible to quickly generate hydraulic pressure when the vane pump is started.

In addition, the vane pump of the present invention has the back pressure grooves provided in the two side plates separately and independently as shown in FIGS.
In particular, the second

back pressure grooves

70B and 71B of the first side plate 7 installed on the two

discharge ports

40 and 41 are provided from the rotor 4 side to the counter rotor 4 side (pump cover 10 side) as described above. Connecting

holes

50 and 51 are provided, respectively.

These

holes

50 and 51 are connected to high-

pressure chambers

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

pressure chambers

60 and 61 each have two discharge ports. 40, 41.
That is, the oil in the second

back pressure grooves

70B and 71B of the first side plate 7 is discharged from the two

discharge ports

40 and 41 through the

respective hole portions

50 and 51 and the

high pressure chambers

60 and 61. The

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 ones, and the oil passages from the back pressure grooves to the discharge ports are also provided separately.
Thereby, two types of high pressure and low pressure oil can be supplied by one unit.

The performance test of the vane pump in the present embodiment will be described with reference to the drawings.
This performance test was performed using a vane pump according to the present invention (hereinafter referred to as “the product of the present invention”) and a conventional vane pump (hereinafter referred to as a “conventional product”) in a very low temperature (−30 ° C.) atmosphere. The purpose was to confirm.
FIG. 10 shows the overall configuration of the performance test apparatus 200 used in this performance test.

First, the product of the present invention used in this performance test was a vane pump having the configuration shown in FIGS.
In contrast, the conventional product does not have the third

back pressure grooves

70C, 71C, 80C, 81C of the first side plate 7 shown in FIG. 4 and the second side plate 8 shown in FIG. The (first and second) side plates having the form of back pressure grooves in which 70A, 71A, 80A, 81A and second

back pressure grooves

70B, 71B, 80B, 81B are integrated were used.
Other components are the same as those of the present invention.

Next, the performance test apparatus 200 includes a motor 220, a pressure valve 240, and the like in addition to the vane pump 201, and these equipments are connected to each other via oil passages 261 to 264.
As the shaft of the motor 220 rotates, 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 tachometer 230 installed on the shaft.

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

discharge ports

40 and 41 shown in FIG. 2 and sent to the pressure valve 240 through the

oil passages

262 and 263.
The oil pressure (hydraulic pressure) of the performance test apparatus 200 is adjusted according to the degree of opening and closing of the pressure valve 240.
The oil coming out of the pressure valve 240 is finally returned to the oil pan 210 through the oil passage 264.

Further, the complete set of equipment such as the vane pump 201, the motor 220, and the pressure valve 240 is housed in a temperature-controlled room 270 as shown in FIG. 10, and the test atmosphere (test temperature) can be freely adjusted. Yes.

The performance test apparatus 200 includes a power supply for the motor 220 (not shown), electrical wiring for controlling the tachometer 230 and the pressure converter 250, various measurements for measuring the rotation speed of the motor 220 and the oil pressures of the oil passages 261 to 264. Equipment etc. are also provided.

Next, a test method for this performance test will be described.
The oil is supplied to the vane pump 201 by rotating the motor 220 with the temperature in the temperature-controlled room 270 of the performance test apparatus 200 shown in FIG.
At the same time, the pressure (discharge pressure) of oil from the vane pump 201 is set to 1.8 MPa by the pressure valve 240.

After a certain time has passed in this state, the motor 220 is stopped and the supply of oil to the vane pump 201 is stopped.
Thereafter, the temperature in the temperature-controlled room 270 is changed to −30 ° C., and a set of equipment such as the vane pump 201 is held in that state for 8 hours.

After 8 hours have passed since the temperature in the temperature-controlled room 270 reached −30 ° C., the motor 220 is started at a rotation speed of 200 rpm and held for 1.5 seconds.
Thereafter, the rotation speed of the motor 220 is changed from 200 rpm to 1800 rpm.
In this performance test, the change in the pressure (discharge pressure) of the oil discharged from the vane pump 201 in about 12 seconds after the motor 220 is started at 200 rpm is measured over time using the pressure converter 250 and a measuring device (not shown). It was measured.

The performance test results using the vane pumps of the present invention and the conventional product will be described below with reference to the drawings.
FIG. 11 shows the result (graph) of the performance test using the product of the present invention, and FIG. 12 shows the result (graph) of the performance test using the conventional product.

In the graphs showing the test results, the horizontal axis represents the elapsed time (unit: second) since the rotation speed of the motor 220 was started at 200 rpm in both FIG. 11 and FIG. 12, and the right vertical axis is shown in FIG. The rotation speed (unit: rpm) of the motor 220 measured by the tachometer 230, and the left vertical axis respectively represent the pressure (unit: MPa) of oil discharged from the vane pump 201 measured by the pressure converter 250 shown in FIG. ing.
The horizontal axis in both drawings represents the time when the motor starts to start (0 seconds).

Further, in the graphs of FIG. 11 and FIG. 12, the time zone from when the motor starts up until the rotation speed reaches 200 rpm until 1.5 seconds elapses is confirmed as A1, B1, and then the oil discharge from the vane pump is confirmed. The time until the oil pressure reached the maximum value (maximum pressure) was classified as A3 and B3.

In the performance test using the product of the present invention, first, as shown in FIG. 11, as a preparatory operation, the motor was started and about 0.5 seconds later, the rotation speed reached 200 rpm, and the state was maintained for 1.5 seconds (FIG. 11). A1 section shown in FIG.
Thereafter, the rotation speed of the motor was changed from 200 rpm to 1800 rpm.

When the rotation speed of the motor was changed to 1800 rpm, the pressure increase of the oil (pressure increase due to oil) was confirmed instantaneously (after 0.046 seconds: section A2 shown in FIG. 11) from the vane pump of the present invention.
About 0.6 seconds after the pressure increase of the oil by the vane pump is confirmed, the oil pressure reaches the maximum value (about 4.2 MPa) (A3 section shown in FIG. 11), and then the oil pressure is about 1.7 MPa. It was confirmed that the pressure was maintained.

On the other hand, in the performance test using the conventional product, as shown in FIG. 12, as in the case of the performance test using the product of the present invention, after the motor rotation speed reaches 200 rpm, it is held for 1.5 seconds. (B1 section shown in FIG. 12), the rotation speed of the motor was changed from 200 rpm to 1800 rpm.

When the motor rotation speed was changed to 1800 rpm, pressure increase of the oil was confirmed about 4.6 seconds after the motor rotation speed change from the conventional product (B2 section shown in FIG. 12).
About 0.2 seconds after the pressure increase of the oil by the vane pump is confirmed (B3 section shown in FIG. 12), the oil pressure reaches the maximum value (about 5 MPa), and thereafter the performance test result of the product of the present invention is the same. The oil pressure dropped to about 1.7 MPa, and the pressure was maintained.

Based on the above test results, comparing the starting performance of the vane pump in an extremely low temperature (-30 ° C) usage environment, the conventional vane pump (conventional product) receives oil as the motor rotates and then discharges the oil. It took about 4.6 seconds until the operation started (until the vane pump started).

On the other hand, in the vane pump of the present invention, the oil is instantaneously discharged to the outside of the vane pump after receiving the supply of the oil via the suction port, that is, the vane pump may be instantaneously started as the number of rotations of the motor increases. confirmed.

Since the vane pump according to the present invention can control a plurality of discharge pressures and has excellent startability, it can be used for a vane pump for various purposes.

Claims

At least a pump body having a suction port, a cam ring housed in a recess of the pump body, a rotor housed in the cam ring and having a plurality of vane grooves formed radially on the outer circumferential surface, and the plurality A plurality of vanes fitted in the vane grooves, a first side plate disposed on one end surface side of the cam ring and on the discharge port side, and on the other end surface side of the cam ring on the suction port side. A vane pump comprising: a second side plate that is arranged; and a pump cover that has two discharge ports and covers an opening portion of the recess of the pump body,
A pair of independent back pressure grooves are formed on the rotor side of the first and second side plates,
The back pressure groove includes a first back pressure groove,
A second back pressure groove having a groove length shorter than the first back pressure groove;
The first back pressure groove and the second back pressure groove are connected, and the first back pressure groove and the third back pressure groove are narrower than the second back pressure groove. Vane pump characterized by
The second back pressure groove of the first side plate has a hole penetrating from the rotor side of the first side plate to the opposite side of the rotor,
2. The vane pump according to claim 1, wherein the vane pump is connected to a high-pressure chamber formed by a recess provided in the pump cover and the first side plate through the hole.
The vane pump according to claim 1 or 2, wherein a groove depth of the first back pressure groove becomes deeper as it approaches the third back pressure groove.