JP6997597B2 - Oil pump - Google Patents

Description

The present invention relates to a technical field of an oil pump having an outer rotor and an inner rotor that are rotated relative to the pump housing.

Hydraulic oil is supplied to various hydraulic mechanisms operated by hydraulic pressure such as a clutch mechanism, a brake mechanism, and a transmission mechanism in a vehicle for smooth operation and protection. Hydraulic oil is supplied to such a hydraulic mechanism from an oil pump via a line pressure circuit, and hydraulic oil is sucked into the oil pump from an oil tank.

There are two types of oil pumps in which an inner rotor having external teeth and an outer rotor having internal teeth are rotatably supported with respect to the case body in an eccentric state. In this type of oil pump, a suction port and a discharge port are formed in the case body of the pump housing, and the volume of the space formed as a pump chamber between the inner rotor and the outer rotor is the rotation of the inner rotor and the outer rotor. As a result, the pressure in the pump chamber is changed so that the hydraulic oil is sucked from the suction port and the hydraulic oil is discharged from the discharge port.

In such an oil pump, as described above, the pressure in the pump chamber is changed to suck the hydraulic oil from the suction port and discharge the hydraulic oil from the discharge port. Therefore, the pump is pumped in the compression process of the pump chamber. As the pressure in the chamber rises, the drive torque for rotating the inner rotor and the outer rotor increases, which may cause drive loss.

Therefore, in the conventional oil pump, a supply passage for flowing excess hydraulic oil and a pocket portion communicating with the supply passage are formed in the case body, and excess hydraulic oil is supplied from the supply passage when the pump rotation speed increases. Some are configured to flow in the pocket portion and generate auxiliary power for the driving torque by the hydraulic oil flowing in the pocket portion (see, for example, Patent Document 1).

Jitsukaisho 64-36584

By the way, in the oil pump described in Patent Document 1, a rotor groove for a closed pressure leak is formed in the outer rotor, and the hydraulic oil supplied to the pocket portion is configured to flow from the rotor groove to the pump chamber. ing.

Therefore, the hydraulic oil flowing from the rotor groove to the pump chamber may increase the pressure in the pump chamber and increase the drive torque, or the flow state from the pocket to the pump chamber may become unstable depending on the pressure in the pump chamber. There is.

Therefore, it is an object of the present invention to reduce the drive loss while ensuring a stable flow state of the hydraulic oil.

The oil pump according to the present invention has a supply groove for supplying hydraulic oil on the outer peripheral portion and has a rotatable outer rotor, a rotatable inner rotor inside the outer rotor, and a suction port for sucking hydraulic oil. A pump housing having a discharge port for discharging hydraulic oil sucked from the suction port to a line pressure circuit, a support recess for rotatably supporting the outer rotor and the inner rotor, and the outer peripheral surface of the outer rotor are separated from each other. The pump housing is provided with a sliding member that is movable in the contacting direction, is urged in the direction approaching the outer peripheral surface, and receives the pressure of the hydraulic oil supplied to the supply groove, and flows into the line pressure circuit in the pump housing. A supply path for flowing a part of the hydraulic oil to the supply groove and a discharge path for discharging the hydraulic oil supplied to the supply groove are formed, and the supply groove is operated to be flowed to the line pressure circuit. Hydraulic oil is supplied from the supply path according to the amount of oil, and the sliding member is slid on the outer peripheral surface as the outer rotor rotates, and the sliding member is projected into the supply groove. Auxiliary power in the rotational direction is applied to the outer rotor by the hydraulic oil supplied to the supply groove.

As a result, the hydraulic oil supplied to the supply groove imparts auxiliary power in the rotational direction to the outer rotor, and the hydraulic oil supplied to the supply groove and imparting auxiliary power to the outer rotor is discharged from the discharge path.

Secondly, in the above-mentioned oil pump according to the present invention, a pressurized passage communicating with the supply passage is formed in the pump housing, and the sliding member is flown by the hydraulic oil flowing in the pressurized passage. It is desirable to be urged in a direction approaching the outer peripheral surface.

As a result, the sliding member is urged in the direction in contact with the outer peripheral surface of the outer rotor by the hydraulic oil flowing in the pressurized path, so that a dedicated member for urging the sliding member is not required.

Thirdly, in the oil pump according to the present invention described above, it is desirable to provide an urging spring that urges the sliding member in a direction approaching the outer peripheral surface.

As a result, the sliding member is urged in the direction in contact with the outer peripheral surface of the outer rotor by the urging spring, so that the sliding member is urged regardless of the pressure of the hydraulic oil.

Fourth, in the oil pump according to the present invention described above, an assist circuit is provided which is communicated with the line pressure circuit and the supply path, and the hydraulic oil is flowed toward the lubricating portion by being communicated with the line pressure circuit. A lubricating pressure circuit is provided, and a line pressure return valve that opens and closes according to the pressure of the hydraulic oil flowing in the lubricating pressure circuit is connected to the assist circuit, and the pressure of the hydraulic oil flowing in the lubricating pressure circuit is connected. It is desirable that a part of the hydraulic oil flowing in the line pressure circuit is flowed from the assist circuit toward the supply groove by opening the line pressure return valve when the pressure is set to a certain level or higher.

As a result, the hydraulic oil is supplied from the assist circuit to the supply groove according to the pressure of the hydraulic oil flowing in the lubrication pressure circuit, so that the excess hydraulic oil imparts auxiliary power to the outer rotor.

Fifth, in the oil pump according to the present invention described above, it is desirable that a plurality of supply grooves are formed so as to be separated in the circumferential direction.

As a result, when the outer rotor rotates, hydraulic oil is sequentially supplied to the plurality of supply grooves, and rotational force is applied to the outer rotor.

Sixth, in the oil pump according to the present invention described above, it is desirable that a check valve for regulating the flow of hydraulic oil toward the supply groove is arranged in the discharge passage.

This prevents the backflow of hydraulic oil flowing from the supply groove to the discharge path by the check valve.

Seventh, in the above-mentioned oil pump according to the present invention, it is desirable that the hydraulic oil flowing in the discharge passage is flowed toward the oil tank.

As a result, the hydraulic oil that flows from the supply groove to the discharge path and is discharged to the outside of the oil pump is flowed to the oil tank.

According to the present invention, the hydraulic oil supplied to the supply groove imparts auxiliary power in the rotation direction to the outer rotor, and the hydraulic oil supplied to the supply groove and imparting auxiliary power to the outer rotor is discharged from the discharge path. Therefore, it is possible to reduce the drive loss while ensuring a stable flow state of the hydraulic oil.

2 to 9 show an embodiment of the oil pump of the present invention, and this figure is an exploded perspective view of the oil pump. It is a perspective view of a rotor unit. It is sectional drawing which shows a part of an oil pump. It is a schematic diagram which shows the flow circuit and the like. It is a schematic diagram which shows the state which the hydraulic oil is not supplied to the supply groove. It is a schematic diagram which shows the state which the hydraulic oil is supplied to the supply groove. It is sectional drawing which shows the state which the hydraulic pressure of hydraulic oil is applied to the outer rotor. It is sectional drawing which shows the state which the hydraulic oil is discharged from a supply groove. It is sectional drawing which shows the structure which the sliding member was urged by the urging spring.

Hereinafter, embodiments for carrying out the oil pump of the present invention will be described with reference to the accompanying drawings.

In the following description, the direction of the rotation axis of the oil pump is defined as the vertical direction, and the vertical, front, rear, left, and right directions are shown. However, the directions shown below, up, down, front, back, left, and right are for convenience of explanation, and the implementation of the present invention is not limited to these directions.

<Oil pump configuration>
The oil pump 1 has an outer rotor 2, an inner rotor 3, and a pump housing 4 (see FIGS. 1 and 2).

The outer rotor 2 is formed in a cylindrical shape that is penetrated vertically, and the internal space is formed as an arrangement hole 2a. Internal teeth 2b, 2b, ... Are provided on the inner peripheral portion of the outer rotor 2.

Supply grooves 5, 5, ... Opened outward are formed on the outer peripheral portion of the outer rotor 2 at equal intervals in the circumferential direction (see FIGS. 1 to 3). Therefore, the outer peripheral surface 6 of the outer rotor 2 is a portion where the supply grooves 5, 5, ... Are not formed, and the outwardly convex arcuate curved surface portions 7, 7, ... And the supply groove 5, ... Groove forming portions 8, 8, ... Which are the portions where 5, ... Are formed are alternately formed.

The groove forming portion 8 has a vertical surface 8a substantially orthogonal to the curved surface portion 7, an intermediate surface 8b oriented substantially in the radial direction of the outer rotor 2 and substantially orthogonal to the vertical surface 8a, and outward as separated from the intermediate surface 8b. The inclined surface 8c that is displaced to is continuously formed in order.

The inner rotor 3 is rotatably arranged in the arrangement hole 2a of the outer rotor 2 and has a coupling hole 3a that is vertically penetrated in the central portion. External teeth 3b, 3b, ... Are provided on the outer peripheral portion of the inner rotor 3. The number of outer teeth 3b, 3b, ... Of the inner rotor 3 is one less than the number of internal teeth 2b, 2b, ... Of the outer rotor 2.

The shaft 9 is coupled to the inner rotor 3 in a state of being inserted into the coupling hole 3a. The shaft 9 is rotated in the axial direction by the driving force of a driving source (not shown).

The inner rotor 3 is arranged in the arrangement hole 2a in a state of being eccentric with respect to the outer rotor 2. The rotor unit 10 is composed of the outer rotor 2 and the inner rotor 3.

The pump housing 4 is configured by connecting the case 11 and the cover 12 at the top and bottom.

The case 11 is formed with a circular support recess 13 opened upward. The curvature of the peripheral surface 14 forming the support recess 13 is substantially the same as the curvature of the curved surfaces 7, 7, ... On the outer peripheral surface 6 of the outer rotor 2.

In the case 11, a shaft insertion hole 16 penetrated up and down is formed in the central portion of the bottom surface portion 15 forming the support recess 13. In the case 11, a suction port 17 and a discharge port 18 opened upward are formed on the bottom surface portion 15, respectively. The suction port 17 and the discharge port 18 are formed so as to be separated from each other in the circumferential direction.

The case 11 is formed with a suction hole 19 and a discharge hole 20 which are opened upward on opposite sides of the support recess 13. The suction hole 19 communicates with the suction port 17 inside the case 11, and the discharge hole 20 communicates with the discharge port 18 inside the case 11.

A supply path 21 through which hydraulic oil flows is formed in the case 11 (see FIG. 3). One end of the supply path 21 is opened in the peripheral surface 14 forming the support recess 13. A pressurization path 22 communicating with the supply path 21 is formed in the case 11, and one end of the pressurization path 22 is opened to the peripheral surface 14 and the other end is communicated with the supply path 21.

A sliding member 23 is movably supported on one end side of the pressurization path 22. The sliding member 23 is formed in a plate shape or a shaft shape, and is movable with respect to the pressurization path 22 in a state where a part thereof can protrude into the support recess 13. The sliding member 23 has an end portion 23a on the side protruding from the support recess 13 formed in an outwardly convex curved surface shape. The sliding member 23 is urged in the direction of protruding into the support recess 13 by the hydraulic oil flowing into the pressurized passage 22 through the supply passage 21.

A discharge path 24 is formed in the case 11. One end of the discharge path 24 is opened in the peripheral surface 14 forming the support recess 13. A check valve 25 is arranged in the middle portion of the discharge path 24. The check valve 25 has an on-off rod 25a and a spring member 25b, and the on-off rod 25a is urged by the spring member 25b in a direction of closing the discharge path 24.

One end of the air vent hole 26 is communicated with the case 11 in the space where the check valve 25 is arranged. The other end of the air bleeding hole 26 is opened on the outer surface of the case 11. The space in which the check valve 25 is arranged is opened to the atmosphere by the air vent hole 26, and a stable moving state of the on-off rod 25a is ensured.

An insertion hole 27 is formed in a substantially central portion of the cover 12. The cover 12 is formed with a suction hole 28 and a discharge hole 29 which are vertically penetrated on opposite sides of the insertion hole 27, respectively.

The cover 12 is coupled to the case 11 from above in a state where the outer rotor 2 and the inner rotor 3 are arranged in the support recess 13. In a state where the cover 12 is coupled to the case 11, the shaft 9 is inserted into the shaft insertion hole 16 of the case 11, the coupling hole 3a of the inner rotor 3, and the insertion hole 27 of the cover 12, and is fixed to the coupling hole 3a. Therefore, the shaft 9 is rotated integrally with the inner rotor 3 with respect to the pump housing 4. At this time, the inner teeth 2b, 2b, ... Of the outer rotor 2 and the outer teeth 3b, 3b, ... Of the inner rotor 3 are repeatedly meshed with and separated from each other, and the rotational force of the inner rotor 3 is applied to the outer rotor 2. Granted, the outer rotor 2 is rotated with respect to the pump housing 4 at a rotation speed different from that of the inner rotor 3.

In a state where the cover 12 is coupled to the case 11, the suction hole 28 of the cover 12 and the suction hole 19 of the case 11 are communicated vertically, and the suction hole 28 and the suction hole 19 form a suction path 30 for hydraulic oil. Further, in a state where the cover 12 is coupled to the case 11, the discharge hole 29 of the cover 12 and the discharge hole 20 of the case 11 are communicated vertically, and the discharge hole 29 and the discharge hole 20 form a hydraulic oil discharge path 31. Ru.

When the outer rotor 2 and the inner rotor 3 are arranged in the support recess 13, the case 11 and the cover 12 are coupled to each other by the outer rotor 2, the inner rotor 3, the bottom surface portion 15 of the case 11, and the lower surface of the cover 12. A plurality of spaces are formed, and each of these spaces is referred to as a pump chamber 32, 32, ....

<Operation of oil pump>
In the oil pump 1 configured as described above, the hydraulic oil is sucked from the suction passage 30, and the sucked hydraulic oil is flowed from the suction port 17 to the pump chambers 32, 32, .... At this time, the outer rotor 2 and the inner rotor 3 are rotated in the same direction at different rotation speeds, and the pump chambers 32, 32, ... Repeat the expansion and contraction of the volume. By repeatedly expanding and contracting the volumes of the pump chambers 32, 32, ..., The pressure of the hydraulic oil flowing into the pump chambers 32, 32, ... Is changed, and the hydraulic oil is discharged from the discharge port 18. The hydraulic oil is flown into the passage 31 and the flowed hydraulic oil is discharged from the discharge passage 31.

<Structure of hydraulic oil flow circuit, etc.>
Next, a configuration of a hydraulic oil flow circuit or the like sucked into the oil pump 1 or discharged from the oil pump 1 will be described (see FIG. 4).

As the flow circuit, the suction circuit 40 that sucks the hydraulic oil 50 into the oil pump 1, the line pressure circuit 41 through which the hydraulic oil 50 discharged from the oil pump 1 flows, and the hydraulic oil 50 are supplied to the lubricating portion 100. A lubrication pressure circuit 42, an assist circuit 43 for applying auxiliary power to the outer rotor 2, and a discharge circuit 44 for discharging the hydraulic oil 50 supplied from the assist circuit to the oil pump 1 are provided.

The suction circuit 40 is an oil passage that communicates with the suction passage 30 of the oil pump 1 and causes the hydraulic oil 50 flowing from the oil tank 200 to flow toward the suction passage 30.

The line pressure circuit 41 is communicated with the discharge path 31 of the oil pump 1, and the hydraulic oil 50 discharged from the discharge path 31 flows toward, for example, a hydraulic mechanism 300 such as a clutch mechanism, a brake mechanism, or a transmission mechanism. Is. The line pressure circuit 41 is provided with a first branch path 41a and a second branch path 41b.

A line pressure adjusting valve 45 is connected to the first branch path 41a. The line pressure adjusting valve 45 has a function of adjusting the pressure of the hydraulic oil 50 flowing through the line pressure circuit 41. A line pressure return valve 46 is connected to the second branch passage 41b.

The first branch path 41a communicates with the lubrication pressure circuit 42 via the line pressure adjusting valve 45. Therefore, the amount of oil of the hydraulic oil 50 flowing in the lubrication pressure circuit 42 is controlled by the line pressure adjusting valve 45.

The lubrication pressure circuit 42 is an oil passage for flowing the hydraulic oil 50 toward the lubrication portion 100 of various gear mechanisms, rotation mechanisms, engine parts, and the like. An orifice 47 is connected to the lubrication pressure circuit 42, and the amount of oil of the hydraulic oil 50 flowing from the lubrication pressure circuit 42 toward the lubrication portion 100 is limited by the orifice 47.

The lubrication pressure circuit 42 is provided with a return branch path 42a on the upstream side of the orifice 47, and the return branch path 42a is communicated with the line pressure return valve 46.

The assist circuit 43 communicates with the line pressure return valve 46 and the supply path 21 of the oil pump 1. Therefore, when the hydraulic oil 50 is flowed in the assist circuit 43, the flowed hydraulic oil 50 is supplied to the supply grooves 5, 5, ... Of the outer rotor 2 via the supply path 21 and is supplied to the pressurization path 22. Is flowed to.

The discharge circuit 44 communicates with the discharge path 24 of the oil pump 1.

<Operation of flow circuit, etc.>
In the above configuration, when the rotor unit 10 of the oil pump 1 is in a low rotation state, the amount of oil of the hydraulic oil 50 flowing in the line pressure circuit 41 and the lubrication pressure circuit 42 is small, and the lubrication pressure in the lubrication pressure circuit 42 is high. It has been made smaller. In this case, the line pressure return valve 46 is closed, and the line pressure return valve 46 is in a state where the flow from the second branch path 41b to the assist circuit 43 is not performed (see FIG. 5). Therefore, the hydraulic oil 50 is not supplied from the supply path 21 to the supply grooves 5, 5, ... Of the outer rotor 2.

On the other hand, when the rotor unit 10 of the oil pump 1 is in a high rotation state, the amount of oil of the hydraulic oil 50 flowing in the line pressure circuit 41 and the lubrication pressure circuit 42 increases, and the lubrication pressure in the lubrication pressure circuit 42 becomes high. Has been done. In this case, the line pressure return valve 46 is opened from the closed state by the lubrication pressure, and the second branch path 41b and the assist circuit 43 are communicated with each other by the line pressure return valve 46 (see FIG. 6).

When the second branch path 41b and the assist circuit 43 are communicated with each other, the hydraulic oil 50 flows from the line pressure circuit 41 to the assist circuit 43, and the hydraulic oil 50 flowed to the assist circuit 43 flows from the supply path 21 to the outer rotor 2. It is sequentially supplied to the supply grooves 5, 5, ... The hydraulic oil 50 is supplied between the sliding member 23 of the supply groove 5 and the vertical surface 8a in the rotation direction S (see FIG. 3) of the outer rotor 2.

When the hydraulic oil 50 is supplied to the supply groove 5 in this way, hydraulic pressure is applied to each surface of the groove forming portion 8 and the surface of the sliding member 23 on the vertical surface 8a side, and the hydraulic oil of the pressurized passage 22 is applied. The end portion 23a of the sliding member 23 urged by the 50 is slid in order to the groove forming portion 8 and the curved surface portion 7 of the outer rotor 2, and the hydraulic pressure of the hydraulic oil 50 acts as an auxiliary power for the rotation of the outer rotor 2. (See FIG. 7).

Therefore, the rotor unit 10 is rotated in the rotation direction by the driving force of the driving source transmitted via the shaft 9 and the hydraulic auxiliary power of the hydraulic oil 50 supplied from the line pressure circuit 41 via the assist circuit 43 and the supply path 21. It is rotated to S.

As described above, in the oil pump 1, the pump housing 4 is formed with a pressurized passage 22 communicating with the supply passage 21, and the sliding member 23 is formed on the outer peripheral surface by the hydraulic oil 50 flowing in the pressurized passage 22. It is being urged in the direction of approaching 6.

Therefore, since the sliding member 23 is urged in the direction in contact with the outer peripheral surface 6 of the outer rotor 2 by the hydraulic oil 50 flowing in the pressurization path 22, a dedicated member for urging the sliding member 23 is provided. It is not necessary, and the sliding member 23 can be reliably urged after reducing the number of parts.

When the supply groove 5 to which the hydraulic oil 50 is supplied reaches the position corresponding to the discharge path 24 by the rotation of the outer rotor 2, the hydraulic oil 50 supplied to the supply groove 5 flows into the discharge path 24 (FIG. 8). reference). When the hydraulic oil 50 flows from the supply groove 5 to the discharge passage 24, the check valve 25 is opened by the hydraulic pressure of the hydraulic oil 50 flowing in the discharge passage 24, and the hydraulic oil 50 flows from the discharge passage 24 to the discharge circuit 44. Through, for example, the oil is flowed toward the oil tank 200.

When the hydraulic oil 50 does not flow from the supply groove 5 to the discharge path 24, the check valve 25 prevents the hydraulic oil 50 from flowing back from the discharge circuit 44 to the supply groove 5 (see FIG. 7). ).

<Others>
The above shows an example in which the sliding member 23 is urged by the hydraulic oil 50 flowing into the pressurized passage 22 through the supply passage 21, but the sliding member 23 is urged by the urging spring 48. (See FIG. 9).

For example, the pressurization path 22 is not formed in the case 11, the arrangement space 49 opened in the support recess 13 is formed in the case 11, the urging spring 48 is arranged in the arrangement space 49, and the sliding member. The 23 may be configured to be urged by the urging spring 48 in a state where the 23 can protrude into the support recess 13.

With this configuration, the sliding member 23 is urged by the urging spring 48 in the direction in contact with the outer peripheral surface 6 of the outer rotor 2, so that the sliding member 23 is attached regardless of the pressure of the hydraulic oil 50. The sliding member 23 can be reliably urged regardless of the pressure of the hydraulic oil 50 that is urged and supplied to the supply grooves 5, 5, ....

<Summary>
As described above, in the oil pump 1, a sliding member 23 that receives the pressure of the hydraulic oil 50 supplied to the supply groove 5 is provided, and a supply path 21 and a discharge path 24 are formed in the pump housing 4. The hydraulic oil 50 is supplied from the supply path 21 to the supply groove 5 according to the amount of oil of the hydraulic oil 50 flowing in the line pressure circuit 41, and the sliding member 23 is attached to the outer peripheral surface 6 as the outer rotor 2 rotates. Auxiliary power in the rotation direction is applied to the outer rotor 2 by the hydraulic oil 50 supplied to the supply groove 5 while being slid.

Therefore, the hydraulic oil 50 supplied to the supply groove 5 imparts auxiliary power in the rotational direction to the outer rotor 2, and the hydraulic oil 50 supplied to the supply groove 5 and imparts auxiliary power to the outer rotor 2 is discharged. Since it is discharged from 24, it is possible to reduce the drive loss while ensuring a stable flow state of the hydraulic oil 50.

Further, a line pressure return valve 46 that opens and closes according to the pressure of the hydraulic oil 50 flowing in the lubricating pressure circuit 42 is connected to the assist circuit 43, and the pressure of the hydraulic oil 50 flowing in the lubricating pressure circuit 42 is constant. When the above is done, a part of the hydraulic oil 50 flowing in the line pressure circuit 41 is flowed from the assist circuit 43 toward the supply groove 5 by opening the line pressure return valve 46.

Therefore, the hydraulic oil 50 is supplied from the assist circuit 43 to the supply groove 5 according to the pressure of the hydraulic oil 50 flowing in the lubrication pressure circuit 42, so that the excess hydraulic oil 50 imparts auxiliary power to the outer rotor 2. It is possible to reduce the drive loss of the oil pump 1 while ensuring the high operating efficiency of the hydraulic oil 50.

Further, since a plurality of supply grooves 5, 5, ... Are formed apart from each other in the circumferential direction, the hydraulic oil 50 is sequentially supplied to the plurality of supply grooves 5, 5, ... When the outer rotor 2 rotates. A rotational force is applied to the outer rotor 2, and auxiliary power can be intermittently applied when the outer rotor 2 is rotated.

Furthermore, since the check valve 25 that regulates the flow of the hydraulic oil 50 toward the supply groove 5 is arranged in the discharge path 24, the check valve 25 causes the flow from the supply groove 5 to the discharge path 24. The backflow of the oil 50 is prevented, and the hydraulic oil 50 flowing in the discharge path 24 can be reliably discharged to the outside of the oil pump 1 to prevent a decrease in the auxiliary power for the outer rotor 2.

In addition, since the hydraulic oil 50 flowing in the discharge passage 24 flows toward the oil tank 200, the hydraulic oil 50 that flows from the supply groove 5 into the discharge passage 24 and is discharged to the outside of the oil pump 1 is in the oil tank. It is flowed to 200, and the utilization efficiency of the hydraulic oil 50 can be improved.

1 ... Oil pump, 2 ... Outer rotor, 3 ... Inner rotor, 4 ... Pump housing, 5 ... Supply groove, 6 ... Outer surface, 13 ... Support recess, 17 ... Suction port, 18 ... Discharge port, 21 ... Supply path, 22 ... Pressurization path, 23 ... Sliding member, 24 ... Discharge path, 25 ... Check valve, 41 ... Line pressure circuit, 42 ... Lubrication pressure circuit, 43 ... Assist circuit, 44 ... Discharge circuit, 46 ... Line pressure return Valve, 200 ... oil tank, 48 ... urging spring

Claims (7)

An outer rotor that has a supply groove for supplying hydraulic oil to the outer circumference and is rotatable,
An inner rotor that can rotate inside the outer rotor and
A pump housing having a suction port for sucking hydraulic oil, a discharge port for discharging hydraulic oil sucked from the suction port to a line pressure circuit, and a support recess for rotatably supporting the outer rotor and the inner rotor, respectively.
It is provided with a sliding member that is movable in a direction that separates from and contacts the outer peripheral surface of the outer rotor, is urged in a direction that approaches the outer peripheral surface, and receives the pressure of hydraulic oil supplied to the supply groove.
The pump housing is formed with a supply path for flowing a part of the hydraulic oil flowing in the line pressure circuit into the supply groove and a discharge path for discharging the hydraulic oil supplied to the supply groove.
The hydraulic oil is supplied to the supply groove from the supply path according to the amount of hydraulic oil flowing in the line pressure circuit.
The sliding member is slid on the outer peripheral surface with the rotation of the outer rotor, and the sliding member is projected into the supply groove and the hydraulic oil supplied to the supply groove causes the outer rotor to rotate in the rotational direction. An oil pump that is given auxiliary power. A pressurization path communicating with the supply path is formed in the pump housing.
The oil pump according to claim 1, wherein the sliding member is urged in a direction approaching the outer peripheral surface by hydraulic oil flowing in the pressurized path. The oil pump according to claim 1, wherein an urging spring is provided to urge the sliding member in a direction approaching the outer peripheral surface. An assist circuit that communicates with the line pressure circuit and the supply path is provided.
A lubrication pressure circuit that communicates with the line pressure circuit and allows hydraulic oil to flow toward the lubrication section is provided.
A line pressure return valve that opens and closes according to the pressure of the hydraulic oil flowing in the lubricating pressure circuit is connected to the assist circuit.
When the pressure of the hydraulic oil flowing in the lubricating pressure circuit becomes a certain level or higher, the line pressure return valve is opened, so that a part of the hydraulic oil flowing in the line pressure circuit is said from the assist circuit. The oil pump according to claim 1, which is flown toward a supply groove. The oil pump according to claim 1, claim 2, claim 3 or claim 4, wherein a plurality of supply grooves are formed apart from each other in the circumferential direction. The oil pump according to claim 1, claim 2, claim 3, claim 4 or claim 5, wherein a check valve for regulating the flow of hydraulic oil toward the supply groove is arranged in the discharge passage. The oil pump according to claim 1, claim 2, claim 3, claim 4, claim 5 or claim 6, wherein the hydraulic oil flowing in the discharge passage is flown toward the oil tank.

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