Hydraulic Circuit

Abstract

The present invention addresses the problem of suppressing an increase in pressure in a hydraulic circuit. In order to solve this problem, this hydraulic circuit has: a first oil path that links to a discharge port of a first oil pump; a second oil path that links to a discharge port of a second oil pump; a hydraulic control circuit in which a first regulator valve is disposed downstream of a confluence point of the first oil path and the second oil path; a third oil path that connects a suction port of the first oil pump and a strainer; a check valve that is provided to the third oil path and restricts movement of oil toward the strainer side; and a relief valve that is provided to the third oil path and discharges oil in the third oil path to the outside when the pressure in the third oil path exceeds a reference pressure.

Description

[Technical field]

[0001] The present invention relates to a hydraulic circuit. [Background technology]

[0002] Patent Document 1 discloses a hydraulic oil supply device for a vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-165516 A Summary of the Invention

[0004] In the hydraulic oil supply device, a mechanical oil pump and an electric oil pump pressurize the oil drawn in through a strainer. The pressurized oil is discharged from the discharge ports of the mechanical oil pump and the electric oil pump and supplied to the hydraulic control device. The discharge port of the mechanical oil pump is connected to the hydraulic control device via a first suction pipe, which is connected to a second suction pipe that is connected to the discharge port of the electric oil pump. The first suction pipe and the second suction pipe are provided with check valves for preventing backflow of oil to the mechanical oil pump and the electric oil pump, respectively.

[0005] In this type of hydraulic oil supply device, when the mechanical oil pump (mecha oil pump) is driven and the pressure in the first suction pipe increases, there is a possibility that oil (hydraulic oil) will leak from the check valve to the electric oil pump (electric oil pump) side. If the electric oil pump does not have a mechanism for releasing pressure, the pressure in the circuit connecting the electric oil pump and the strainer will rise, which may cause a gap to appear in the seal at the connection with the circuit, resulting in a leakage of hydraulic oil.

[0006] Therefore, in a drive unit (power transmission unit) equipped with two pumps of this type, it is necessary to suppress the pressure rise in the hydraulic circuit.

[0007] One aspect of the present invention is a first oil passage communicating with a discharge port of the first oil pump; a second oil passage communicating with a discharge port of the second oil pump; a hydraulic control circuit in which a first pressure regulating valve is disposed downstream of a junction of the first oil passage and the second oil passage; a third oil passage connecting a suction port of the first oil pump and a strainer; A hydraulic circuit having a check valve provided in the third oil passage and restricting movement of oil toward the strainer, The invention further comprises a relief valve that is provided in the third oil passage and that discharges the oil in the third oil passage to the outside when the pressure in the third oil passage exceeds a reference pressure.

[0008] According to one aspect of the present invention, a pressure increase in a hydraulic circuit can be suppressed. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing a schematic configuration of a power transmission device. [Diagram 2] FIG. 2 is a view of the case seen from the second cover side. [Diagram 3] FIG. 3 is a schematic cross-sectional view of the housing taken along line AA in FIG. [Figure 4] FIG. 4 is a schematic cross-sectional view of the housing taken along line AA in FIG. [Diagram 5] FIG. 5 is a perspective view of the strainer as viewed from above the upper case side. [Figure 6] FIG. 6 is a diagram illustrating a support structure for the mechanical oil pump in the partition portion. [Figure 7] FIG. 7 is a view of the storage section as seen from the front side of the vehicle. [Figure 8] FIG. 8 is a schematic diagram of a hydraulic circuit. [Figure 9] FIG. 9 is a schematic cross-sectional view of the housing for explaining the third oil passage. [Figure 10] FIG. 10 is a schematic cross-sectional view of the housing for explaining the first oil passage. [Figure 11] FIG. 11 is a schematic cross-sectional view of the housing for explaining the second oil passage. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First, the definitions of terms used in this specification will be explained. The power transmission device is a device that has at least a power transmission mechanism, and the power transmission mechanism is, for example, at least one of a gear mechanism, a differential gear mechanism, and a reduction mechanism. In the following embodiments, an example is given in which the power transmission device has the function of transmitting the output rotation of the engine, but the power transmission device may be one that transmits the output rotation of at least one of the engine and a motor (rotating electric machine).

[0011] "Axial direction" refers to the axial direction of the rotation shaft of a component constituting the power transmission device. "Radial direction" refers to the direction perpendicular to the rotation shaft of a component constituting the power transmission device. The component is, for example, a motor, a gear mechanism, a differential gear mechanism, etc.

[0012] "Vertical placement" of a control valve means that, in the case of a control valve having a basic configuration in which a separator plate is sandwiched between valve bodies, the valve bodies of the control valve are stacked in a horizontal direction based on the installation state of the power transmission device on the vehicle. The "horizontal direction" here does not mean a horizontal direction in the strict sense, but also includes cases where the stacking direction is inclined relative to the horizontal line.

[0013] Furthermore, "vertically mounted" of the control valve means that the control valve is arranged so that the multiple pressure regulating valves within the control valve are aligned in the direction of a vertical line VL based on the installation state of the power transmission device on the vehicle. "Lined up in the vertical line VL" means that the pressure regulating valves in the control valve are arranged with their positions staggered along the vertical line VL. In this case, the pressure regulating valves do not need to be arranged with their positions completely staggered along the vertical line VL. It also includes the case where the pressure regulating valves are arranged in the vertical line VL with a partial overlap with each other when viewed from the horizontal line.

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a hydraulic circuit according to the present invention will be described by taking as an example a case in which the hydraulic circuit is applied to a power transmission device for a vehicle. FIG. 1 is a schematic diagram illustrating a general configuration of a power transmission device 1 mounted on a vehicle V. As shown in FIG.

[0015] As shown in FIG. 1, a housing HS of the power transmission device 1 is composed of a case 6, a first cover 7, a second cover 8, and a third cover 9. The housing HS accommodates a torque converter T / C, a forward / reverse switching mechanism 2, a variator 3, a reduction gear mechanism 4, a differential gear 5, an electric oil pump EOP, a mechanical oil pump MOP, a control valve CV, a strainer 10, etc. Here, the torque converter T / C, the forward / reverse switching mechanism 2, the variator 3, the reduction gear mechanism 4, and the differential gear 5 are components of the power transmission mechanism.

[0016] In the power transmission device 1, the output rotation of an engine ENG (drive source) is input to a forward / reverse switching mechanism 2 via a torque converter T / C. The rotation input to the forward / reverse switching mechanism 2 is input to a primary pulley 31 of the variator 3 in a forward or reverse rotation.

[0017] In the variator 3, the winding radius of the belt 30 around the primary pulley 31 and the secondary pulley 32 is changed, so that the rotation input to the primary pulley 31 is changed in speed at a desired gear ratio and output from the output shaft 33 of the secondary pulley 32.

[0018] The output rotation of the secondary pulley 32 is input to a differential device 5 (differential gear mechanism) via a reduction gear mechanism 4, and then transmitted to the drive wheels WH, WH via left and right drive shafts 55A, 55B.

[0019] The reduction mechanism 4 has an output gear 41 , an idler gear 42 , a reduction gear 43 , and a final gear 45 . The output gear 41 rotates integrally with the output shaft 33 of the secondary pulley 32 . The idler gear 42 is meshed with the output gear 41 so as to be capable of transmitting rotation. The idler gear 42 rotates integrally with an idler shaft 44. A reduction gear 43 having a smaller diameter than the idler gear 42 is provided on the idler shaft 44. The reduction gear 43 is meshed with a final gear 45 fixed to the outer periphery of a differential case 50 of the differential device 5 so as to be capable of transmitting rotation.

[0020] In the power transmission device 1, the forward / reverse switching mechanism 2, the torque converter T / C, and the output shaft of the engine ENG are arranged coaxially (concentrically) on the rotation axis X1 (first shaft) of the primary pulley 31. The output shaft 33 of the secondary pulley 32 and an output gear 41 are coaxially arranged on a rotation axis X2 (second shaft) of the secondary pulley 32. The idler gear 42 and the reduction gear 43 are coaxially arranged on a common rotation axis X3. The final gear 45 and the drive shafts 55A, 55B are arranged coaxially on a common rotation axis X4. In the power transmission device 1, these rotation axes X1 to X4 are set in a positional relationship in which they are parallel to one another. Hereinafter, these rotation axes X1 to X4 will be collectively referred to as the rotation axis X of the power transmission device 1 (power transmission mechanism) as necessary.

[0021] FIG. 2 is a schematic diagram showing the case 6 as viewed from the second cover 8 side. 2, the strainer 10 and the mechanical oil pump MOP are omitted, and only the area around the connection parts 625 and 627 provided in the partition part 62 is shown. Furthermore, in the enlarged view of FIG. 2, in order to make the position of the opening 620 easier to understand, the area of ​​the opening 620 is shown with cross hatching.

[0022] As shown in FIG. 2, the case 6 has a cylindrical peripheral wall portion 61 and a partition wall portion 62. 1, the partition 62 divides the space inside the peripheral wall 61 into two in the direction of the rotation axis X1. One side of the partition 62 in the direction of the rotation axis X1 is a first chamber S1, and the other side is a third chamber S3. In the case 6, the opening on the first chamber S1 side is sealed by the second cover 8 (torque converter cover) to form a closed first chamber S1. The opening on the third chamber S3 side is sealed by the first cover 7 (side cover) to form a closed third chamber S3. The first chamber S1 accommodates the forward / reverse switching mechanism 2, the reduction mechanism 4, and the differential gear 5. The third chamber S3 accommodates the variator 3.

[0023] In the case 6, a storage section 68 that forms the second chamber S2 is provided on the outer periphery of the peripheral wall section 61 on the vehicle front side. The storage section 68 is provided with an opening facing the vehicle front side. The opening of the storage section 68 is sealed with the third cover 9 to form a closed second chamber S2. The control valve CV and the electric oil pump EOP are disposed in the second chamber S2.

[0024] As shown in Fig. 1, the control valve CV has a basic structure in which a separate plate 940 is sandwiched between valve bodies 941, 941. A hydraulic control circuit 95 (described later) (see Fig. 8) is formed inside the control valve CV. The hydraulic control circuit 95 is provided with a solenoid that is driven based on commands from a control device (not shown), a pressure regulating valve SP (spool valve) that operates based on signal pressure generated by the solenoid, and an oil passage.

[0025] 2, the partition wall 62 of the case 6 is provided in a range that crosses the rotation axes (rotation axes X1 to X4) of the power transmission mechanism. The partition wall 62 is provided in a direction that is approximately perpendicular to the rotation axes (rotation axes X1 to X4).

[0026] The partition wall 62 is provided with through holes 621 , 622 , 624 and a support hole 623 . The through hole 621 is formed around the rotation axis X1. A support wall portion 631 surrounding the through hole 621 rotatably supports the input shaft 34 (see FIG. 1) of the primary pulley 31. A piston (not shown) of the forward / reverse switching mechanism 2 and friction plates (forward clutch, reverse brake) are housed inside a peripheral wall 641 that surrounds the support wall 631.

[0027] The through hole 622 is formed centered on the rotation axis X2. A peripheral wall portion 632 surrounding the through hole 622 supports the output shaft 33 (see FIG. 1) of the secondary pulley 32 for rotation. The support hole 623 is a bottomed hole formed around the rotation axis X3. A peripheral wall portion 633 surrounding the support hole 623 supports the idler shaft 44 (see FIG. 1) rotatably.

[0028] The through hole 624 is formed centered on the rotation axis X4. A support wall portion 634 surrounding the through hole 624 rotatably supports the differential case 50 (see FIG. 1) of the differential device 5. In this manner, partition portion 62 functions as a support wall for input shaft 34 of primary pulley 31, output shaft 33 of secondary pulley 32, idler shaft 44, and differential case 50.

[0029] In the case 6, an area on the vehicle front side of the support wall portion 634 and below the peripheral wall portion 641 serves as an accommodating portion 67 for the strainer 10 and the mechanical oil pump MOP. The storage portion 67 is located in the lower portion inside the case 6 (housing HS). Therefore, the storage portion 67 stores oil OL used for driving and cooling the components of the power transmission mechanism.

[0030] Fig. 3 is a schematic cross-sectional view of the housing HS taken along line AA in Fig. 2. In Fig. 3, the connection between the strainer 10 and the partition wall portion 62 is shown. 3, the accommodation portion 67 is a bottomed space with an opening facing the first chamber S1 side (the right side in FIG. 3). The accommodation portion 67 is formed in the lower part of the case 6 in a range that crosses the direction of the rotation axis X1 of the power transmission device 1 below the peripheral wall portion 641 in which the forward / reverse switching mechanism 2 is housed.

[0031] An opening 620 penetrating the partition 62 in the direction of the rotation axis X1 is formed in the lower part of the partition 62. The first chamber S1 and the third chamber S3 in the case 6 communicate with each other via this opening 620.

[0032] In the accommodation section 67, a connection section 625 of the strainer 10 is provided below the peripheral wall section 641. The connection section 625 is a cylindrical section with a connection port 625a facing the second cover 8 side (the first chamber S1 side). At the rear side of the connection section 625, the oil passage 231 opens.

[0033] 2, oil passage 231 extends linearly within partition portion 62 in a direction away from opening 620. Oil passage 231 is connected to electric oil pump EOP housed in housing portion 68 via oil passage 232 (see FIG. 9) in case 6. Here, oil passage 231 and oil passage 232 constitute a third oil passage, which will be described later.

[0034] 2, in the housing portion 67, a connection portion 627 for connecting to the mechanical oil pump MOP is provided below the oil passage 231. A connection port 627a of the connection portion 627 opens in the same direction as the connection port 625a of the connection portion 625. The connection port 627a of the connection portion 627 is connected to the oil passage 22 provided in the partition portion 62. The oil passage 22 extends below the oil passage 231 toward the housing portion 68 (to the right in the figure) along the oil passage 231. The oil passage 22 is connected to a control valve CV (see FIG. 11) installed in the housing portion 68. Here, the oil passage 22 constitutes a second oil passage on the case 6 side, which will be described later.

[0035] Fig. 4 is a schematic cross-sectional view of the housing HS taken along line AA in Fig. 3. Fig. 4 also shows the arrangement of the strainer 10 and the mechanical oil pump MOP in the housing portion 67. FIG. 5 is a perspective view of the strainer 10 as viewed from above the upper case 11 side.

[0036] As shown in FIGS. 3 and 4, the strainer 10 has a basic configuration in which a filter 19 is disposed in a space S10 formed between the upper case 11 and the lower case 12.

[0037] As shown in Fig. 5, a first connection part 15 is provided on one side part 11a of the upper case 11. The first connection part 15 is a cylindrical member having an oil drainage path 151 therein. A second connection part 16 is provided on the base side of the first connection part 15. As shown in Fig. 3, the second connection part 16 is in the form of a bottomed cylinder having an oil OL drainage path 161 therein.

[0038] The first connection portion 15 and the second connection portion 16 are provided in a direction such that the opening directions of the discharge paths 151, 161 are perpendicular to each other. The discharge passage 161 in the second connection portion 16 and the discharge passage 151 in the first connection portion 15 communicate with the space S10 inside the strainer 10.

[0039] 5, upper case 11 is provided with a recess 17 recessed toward lower case 12 in a region located on an extension of discharge passage 161 in second connection portion 16. Therefore, as shown in FIG 3, check valve 18 can be inserted into discharge passage 161 from the side of strainer 10 without interfering with upper case 11.

[0040] As shown in FIG. 3, the check valve 18 has a cylindrical main body 180 and a valve body 186 . One longitudinal end 180a of the main body 180 is fitted into the discharge passage 161 on the strainer 10 side. The other longitudinal end 180b of the main body 180 is fitted into the connection portion 625 on the partition wall 62 side. Grooves 181, 181 are provided on the outer periphery of one end 180a side of the main body 180 and the outer periphery of the other end 180b side. Seal rings S, S are fitted into the grooves 181, 181, respectively. The seal ring S on the one end 180a side seals the gap between the outer periphery of the main body 180 and the inner periphery of the discharge path 161. The seal ring S on the other end 180b seals the gap between the outer periphery of the main body 180 and the inner periphery of the connection port 625a of the connection part 625. The main body 180 of the check valve 18 also functions as a connecting member that connects the strainer 10 and the connecting portion 625 on the partition wall portion 62 side.

[0041] A valve body 186 is provided inside the main body 180 so as to be displaceable in the direction of an axis X18 (left and right direction in the figure). The axis X18 is a straight line along the longitudinal direction of the main body 180. The axis X18 is also a straight line along the assembly direction of the strainer 10 relative to the partition portion 62.

[0042] A ring-shaped wall portion 182 is provided at one end 180a in the longitudinal direction of the main body portion 180. A through hole 182a is provided at the center of the wall portion 182, penetrating the wall portion 182 in the thickness direction. A support tube 183 is provided at the other end 180b in the longitudinal direction of the main body 180. The support tube 183 is arranged concentrically with the main body 180. The support tube 183 is supported by support beams 184 extending from the inner periphery of the main body 180. A plurality of support beams 184 are provided at intervals in the circumferential direction about the axis X18 of the main body 180. The space between adjacent support beams 184, 184 in the circumferential direction about the axis X18 is an opening 185 through which oil OL can pass.

[0043] A shaft portion 187 of a valve body 186 is inserted into the support cylinder 183 from the direction of the axis X18. The valve body 186 is provided with an abutment portion 188 at one end of a shaft portion 187, the abutment portion 188 having a larger diameter than the shaft portion 187. A spring Sp is fitted onto the shaft portion 187. One end of the spring Sp abuts against the abutment portion 188 from the direction of the axis X18. The other end of the spring Sp abuts against the support tube 183 from the direction of the axis X18. The spring Sp is positioned by the support tube 183. The spring Sp biases the abutment portion 188 of the valve body 186 toward the wall portion 182 (to the right in the figure). The abutment portion 188 of the valve body 186 abuts against the wall portion 182 by the biasing force of the spring Sp. A through hole 182a in the center of the wall portion 182 is closed by the abutment portion 188.

[0044] In the power transmission device 1, when the electric oil pump EOP is driven, oil stored in the lower part of the housing HS is sucked in through the strainer 10. The valve body 186 is displaced in a direction away from the wall portion 182 by the negative pressure generated by driving the electric oil pump EOP. This unseals the through hole 182a, and the oil OL sucked in through the strainer 10 is sucked into the oil passage 231 through the through hole 182a. The sucked oil OL is then finally supplied to the electric oil pump EOP.

[0045] 4, the strainer 10 is assembled to the mechanical oil pump MOP by inserting the tip 15a side of the first connection portion 15 into a connection port 120 on the mechanical oil pump MOP side. The mechanical oil pump MOP is adapted to be assembled to the partition portion 62, and the strainer 10 is supported by the partition portion 62 via the mechanical oil pump MOP.

[0046] 6 is a diagram illustrating the support structure of the mechanical oil pump MOP in the partition portion 62. This Fig. 6 is a schematic cross-sectional view of the mechanical oil pump MOP taken along the line AA in Fig. 4. As shown in FIG. 6, a positioning projection 150 and a discharge port 140 for the oil OL are provided at a portion of the mechanical oil pump MOP facing the partition wall portion 62. In the partition wall 62, an insertion hole 630 and a connection portion 627 are formed on the surface facing the mechanical oil pump MOP.

[0047] The mechanical oil pump MOP is positioned at a predetermined position on the partition wall portion 62 by inserting the protrusion 150 into the insertion hole 630 of the partition wall portion 62. In this state, the mechanical oil pump MOP is fixed to the partition wall portion 62 by a bolt (not shown). When the mechanical oil pump MOP is fixed to the partition wall portion 62, the discharge port 140 of the mechanical oil pump MOP is disposed at a position facing the connection portion 627 on the partition wall portion 62 side, and the discharge port 140 and the connection portion 627 are communicated with each other. The connection portion 627 is connected to the oil passage 22 inside the partition wall portion 62. Therefore, the oil OL discharged from the discharge port 140 of the mechanical oil pump MOP is supplied into the oil passage 22 through the connection portion 627. The oil OL supplied to the oil passage 22 is supplied to the control valve CV inside the accommodation portion 68 (see FIG. 11).

[0048] When the mechanical oil pump MOP is fixed to the partition wall portion 62, the second connection portion 16 of the strainer 10 is connected to the connection portion 625 on the partition wall portion 62 side via the check valve 18 at approximately the same time. In this state, the strainer 10 has a first connection part 15 supported by the mechanical oil pump MOP, and a second connection part 16 attached to the partition part 62 via a check valve 18 (main body part 180) inserted into the second connection part 16.

[0049] Fig. 7 is a view of the accommodation portion 68 as viewed from the front side of the vehicle. In Fig. 7, the second chamber S2 as viewed from the front side of the vehicle is shown typically together with other components of the housing HS (the case 6, the first cover 7, and the second cover 8). The area of ​​the joint portion 683 located on the front side of the page is shown with cross-hatching. The exterior of the control valve CV and the exterior of the electric oil pump EOP are also shown typically.

[0050] 7, the housing 68 has a peripheral wall 681 surrounding the entire outer periphery of the second chamber S2 when viewed from the front side of the vehicle. An inner wall 682 of the peripheral wall 681 has an area overlapping with the first chamber S1, which serves as a partition wall separating the second chamber S2 from the first chamber S1. An end face of the peripheral wall 681 on the front side of the drawing forms a joint 683 with the third cover 9.

[0051] 1, the storage portion 68 is oriented along the rotation axis X of the power transmission device 1. The storage portion 68 is formed to have a range in the direction of the rotation axis X (left-right direction in the figure) that extends from a region adjacent to the peripheral wall portion 61 of the case 6 to the side of the first cover 7.

[0052] In the accommodation portion 68 (second chamber S2), the control valve CV is arranged vertically with the stacking direction of the valve bodies 941, 941 oriented along the vehicle front-rear direction (up-down direction on the paper surface). 7, the control valve CV is vertically oriented in the second chamber S2 so as to satisfy the following conditions: (a) multiple pressure regulating valves SP (spool valves) in the control valve CV are aligned along a vertical line VL (up-down direction) based on the installation state of the power transmission device 1 on the vehicle V, and (b) the direction Xp of the forward and backward movement of the pressure regulating valves SP (spool valves) is oriented along the horizontal line.

[0053] This allows the control valve CV to be disposed vertically in the second chamber S2 while not hindering the back and forth movement of the pressure regulating valve SP (spool valve). This prevents the second chamber S2 from becoming large in the front-rear direction of the vehicle.

[0054] 7, the control valve CV is provided with a discharge port 96 for the oil OL. The oil OL drained from each pressure regulating valve SP is discharged from the discharge port 96. Therefore, the oil OL discharged from the discharge port 96 is stored in the second chamber S2 that houses the control valve CV. In the second chamber S2, a communication hole 94 opens to a lower part of the area of ​​the wall portion 682 overlapping with the first chamber S1. An opening 950 is provided in an upper part of the area of ​​the wall portion 682 overlapping with the first chamber S1. The communication hole 94 and the opening 950 respectively connect the first chamber S1 and the second chamber S2. Therefore, the oil OL in the second chamber S2 is returned to the first chamber S1 through the communication hole 94.

[0055] In the second chamber S2, the control valve CV and the electric oil pump EOP are arranged side by side in the direction of the rotation axis X (left and right direction in FIG. 7). When viewed from the front side of the vehicle, the control valve CV is provided in a positional relationship where it overlaps with the first chamber S1. When viewed from the front side of the vehicle, the electric oil pump EOP is provided in a positional relationship where it overlaps with the third chamber S3.

[0056] The electric oil pump EOP has a discharge port 71 for oil OL and a suction port 72 for oil OL at a portion facing the wall portion 682 on the rear side of the page. The suction port 72 communicates with a connection portion 625 with the strainer 10 via an oil passage 23 (see FIG. 9) provided in the wall portion 682 . The discharge port 71 communicates with a connection port 97 for a control valve CV via an oil passage 21 (see FIG. 10) provided in the wall portion 682.

[0057] FIG. 8 is a schematic diagram of the hydraulic circuit 20 of the power transmission device 1. As shown in FIG. 9 is a schematic cross-sectional view of the housing HS for explaining the third oil passage, which corresponds to a cross-section of the housing HS taken along line BB in FIG. 10 is a schematic cross-sectional view of the housing HS for explaining the first oil passage, which corresponds to a cross-section of the housing HS taken along line CC in FIG. 11 is a schematic cross-sectional view of the housing HS for explaining the second oil passage, which corresponds to a cross-section of the housing HS taken along line DD in FIG.

[0058] As shown in Fig. 8, the hydraulic circuit 20 of the power transmission device 1 includes one mechanical oil pump MOP and one electric oil pump EOP. These oil pumps (the mechanical oil pump MOP and the electric oil pump EOP) suck oil OL stored in the lower part of the housing HS (the first chamber S1 and the third chamber S3) through a common strainer 10. The sucked oil OL is pressurized and then supplied to a hydraulic control circuit 95 in the control valve CV. In the following description, when there is no particular distinction between the mechanical oil pump MOP and the electric oil pump EOP, they will simply be referred to as "oil pump OP."

[0059] The hydraulic circuit 20 further has a first oil passage (oil passage 21, first connecting passage 901), a second oil passage (oil passage 22, second connecting passage 902), a third oil passage (oil passage 23, third connecting passage 903), and a hydraulic control circuit 95. The first oil passage and the second oil passage join at a joining point P in the control valve CV.

[0060] As shown in FIG. 8, the first oil passage is made up of an oil passage 21 on the case 6 side (wall portion 682, partition portion 62) and a first connection passage 901 on the control valve CV side. The oil passage 21 is an oil passage that connects a discharge port 71 of the electric oil pump EOP (first oil pump) and a connection port 97 with the control valve CV. As shown in FIG. 10, oil passage 21 is made up of oil passage 211 extending linearly within partition portion 62 and oil passage 212 extending linearly within wall portion 682 . The oil passage 211 is a blind hole formed in a direction perpendicular to the rotation axis Xm of the mechanical oil pump MOP. The base end of the oil passage 211 is a connection port 97 that opens into the second chamber S2. The oil passage 212 is a blind hole formed in a direction along the rotation axis Xm. Here, the rotation axis Xm is parallel to the rotation axis X of the power transmission device 1. A base end 212a of the oil passage 212 is sealed by a plug PL. A tip end 212b of the oil passage 212 intersects with the oil passage 211 inside the partition wall portion 62. Here, the blind hole refers to a dead-end hole that is open at the base end and not open at the tip end.

[0061] In the control valve CV, a connection portion 911 of a first connection passage 901 opens at a portion facing the connection port 97 of the oil passage 211 . The connection portion 911 is a bottomed hole formed with an opening facing the wall portion 682. The connection portion 911 is formed with an inner diameter D911 larger than the inner diameter D211 of the oil passage 211.

[0062] A valve body 915 is provided at the connection portion 911. The valve body 915 is composed of a cylindrical shaft portion 916 and a contact portion 917 provided at one end of the shaft portion 916. The shaft portion 916 is supported by a cylindrical support portion 912 provided on the connection portion 911 so as to be movable in the direction of an axis X91 along the opening direction of the oil passage 211. A spring Sp is fitted around the support portion 912 and the shaft portion 916. The valve body 915 is biased toward the wall portion 682 by the biasing force of the spring Sp.

[0063] The contact portion 917 is formed with an outer diameter larger than that of the oil passage 211. When the contact portion 917 contacts the wall portion 682, the contact portion 917 is held in a state pressed against the outer circumferential edge surrounding the opening of the oil passage 211 by the biasing force of the spring Sp. In this state, the contact portion 917 is in metal-to-metal contact with the wall portion 682, blocking communication between the oil passage 211 and the first connection passage 901 on the hydraulic control circuit 95 side.

[0064] When the electric oil pump EOP is driven, the valve body 915 is pushed by the oil OL supplied from the oil passage 211 and displaced in a direction away from the wall portion 682. This unseals the oil passage 211, and the oil OL supplied from the electric oil pump EOP side is supplied to the line pressure regulating valve 951 (see FIG. 8) side through the first connection passage 901 in the control valve CV.

[0065] Here, a first connection passage 901 through which the oil OL from the electric oil pump EOP flows merges, between a connection portion 911 and the line pressure regulating valve 951, with a second connection passage 902 through which the oil OL from the mechanical oil pump MOP flows. Therefore, when the mechanical oil pump MOP is driven, the oil OL flows from the second connection passage 902 through the first connection passage 901 into the connection portion 911. Here, when the electric oil pump EOP is not driven, the valve body 915 seals the opening of the oil passage 211, so that the inflow of oil OL into the oil passage 211 on the electric oil pump EOP side is restricted.

[0066] As shown in FIG. 8, the second oil passage is made up of oil passage 22 on the case 6 side (wall portion 682, partition portion 62) and a second connection passage 902 on the control valve CV side. The oil passage 22 is an oil passage that connects a discharge port 140 of a mechanical oil pump MOP (second oil pump) and a connection port 98 with the control valve CV. 11, the oil passage 22 extends linearly within the partition wall portion 62. The oil passage 22 is a blind hole formed in a direction perpendicular to the rotation axis Xm of the mechanical oil pump MOP. The base end of the oil passage 22 is a connection port 98 that opens into the second chamber S2.

[0067] In the control valve CV, a connection portion 921 of a second connection passage 902 opens at a portion facing the connection port 98 of the oil passage 22 . The connecting portion 921 is a bottomed hole formed with an opening facing the wall portion 682. The connecting portion 921 is formed with an inner diameter D921 larger than the inner diameter D221 of the oil passage 22. A valve body 925 is provided at the connection portion 921. The valve body 925 is composed of a cylindrical shaft portion 926 and a contact portion 927 provided at one end of the shaft portion 926. The shaft portion 926 is supported by a cylindrical support portion 922 provided on the connection portion 921 so as to be movable in the direction of an axis X92 along the opening direction of the oil passage 22. A spring Sp is fitted around the support portion 922 and the shaft portion 926. The valve body 925 is biased toward the wall portion 682 by the biasing force of the spring Sp.

[0068] The contact portion 927 is formed with an outer diameter larger than the oil passage 22. When the contact portion 927 contacts the wall portion 682, the contact portion 927 is held in a state pressed against the outer circumferential edge surrounding the opening of the oil passage 22 by the biasing force of the spring Sp. In this state, the contact portion 927 is in metal-to-metal contact with the wall portion 682, blocking communication between the oil passage 22 and the second connection passage 902 on the hydraulic control circuit 95 side.

[0069] When the mechanical oil pump MOP is driven, the valve body 925 is pushed by the oil OL supplied from the oil passage 22 and displaced in a direction away from the wall portion 682. This unseals the oil passage 22, and the oil OL supplied from the mechanical oil pump MOP side is supplied to the line pressure regulating valve 951 (see FIG. 8) side through the second connection passage 902 in the control valve CV.

[0070] Here, the second connection passage 902 through which the oil OL from the mechanical oil pump MOP flows merges, between the connection portion 921 and the line pressure regulating valve 951, with the first connection passage 901 through which the oil OL from the electric oil pump EOP flows. Therefore, when the electric oil pump EOP is driven, the oil OL flows from the first connection passage 901 through the second connection passage 902 into the connection portion 921. Here, when the mechanical oil pump MOP is not driven, the valve body 925 seals the opening of the oil passage 22, so that the inflow of oil OL into the oil passage 22 on the electric oil pump EOP side is restricted.

[0071] In this manner, in the control valve CV, a check valve 91 is provided at a connection portion of the first connection passage 901 with the oil passage 21 (oil passage 211). Furthermore, a check valve 92 is provided at a connection portion of the second connection passage 902 with the oil passage 22. The first connection passage 901 and the second connection passage 902 are oil passages provided within the control valve CV, and constitute a part of the hydraulic control circuit 95 within the control valve CV. 8, an oil passage 904 beyond a junction P of the first connection passage 901 and the second connection passage 902 is connected to a line pressure regulating valve 951. In the oil passage 904, an oil passage 905 that is connected to another regulating valve is connected between the junction P and the line pressure regulating valve 951.

[0072] A hydraulic control circuit 95 in the control valve CV adjusts the operating hydraulic pressure of the power transmission mechanism (forward / reverse switching mechanism 2, variator 3, etc.) from the hydraulic pressure generated by the oil pump OP. The line pressure regulating valve 951 is a regulating valve to which the oil OL is first supplied in the hydraulic control circuit 95. The line pressure regulating valve 951 adjusts the amount of oil OL drained from the line pressure regulating valve 951, thereby adjusting the hydraulic pressure (line pressure) supplied to other regulating valves to which the oil passage 905 is connected. An oil passage 906 extending from an oil OL discharge port 96 is connected to a drain port of the line pressure regulating valve 951. The oil OL discharged from the line pressure regulating valve 951 passes through the oil passage 906 and is discharged from the discharge port 96 into the second chamber S2. A third connection passage 903 is connected to this oil passage 906. Therefore, oil OL discharged from the relief valve 80 of the oil passage 23 is supplied to the oil passage 906 through the third connection passage 903.

[0073] As shown in FIG. 8, the third oil passage is made up of oil passage 23 on the case 6 (wall portion 682, partition portion 62) side and a third connection passage 903 on the control valve CV side. The oil passage 23 connects the suction port 72 of the electric oil pump EOP (first oil pump) and the strainer 10. As shown in FIG. 9, oil passage 23 is made up of oil passage 231 extending linearly within partition portion 62 and oil passage 232 extending linearly within wall portion 682 . The oil passage 231 is a blind hole formed in a direction perpendicular to the rotation axis Xm of the mechanical oil pump MOP. The base end of the oil passage 231 is a connection port 99 that opens into the second chamber S2. The oil passage 232 is a blind hole formed in a direction along the rotation axis Xm of the mechanical oil pump MOP. An opening on the side of a base end 232a of the oil passage 232 is sealed by a plug PL. A tip end 232b of the oil passage 232 intersects with the oil passage 231 inside the partition wall portion 62. In the oil passage 231, the portion on the connection port 99 side of the region where the oil passage 231 and the oil passage 232 intersect is a branch passage 231'.

[0074] In the control valve CV, a connection portion 931 of a third connection passage 903 opens at a portion facing the connection port 99 (branch passage 231') of the oil passage 231. In the region of the branch passage 231' in the oil passage 231, a relief valve 80 is inserted into the connection port 99. The relief valve 80 has a base 81 that fits inside the connection port 99. The base 81 has a small diameter portion 811 and a large diameter portion 812. A wall portion 82 is provided in the small diameter portion 811 on the side opposite the large diameter portion 812. The base 81 is formed into a bottomed cylindrical shape whose small diameter portion 811 side is closed by the wall portion 82. A through hole 82a is provided in the wall portion 82. The through hole 82a penetrates the wall portion 82 in the thickness direction, and allows the oil passage 231 and the space S80 inside the base portion 81 to communicate with each other.

[0075] A support member 83 for the spring Sp is inserted into the area inside the large diameter portion 812 in the space S80. The support member 83 is positioned by a snap ring 84 that engages with the inner periphery of the large diameter portion 812 , and movement in a direction away from the small diameter portion 811 is restricted by the snap ring 84 . One end of the spring Sp abuts against the surface of the support member 83 on the side of the small diameter portion 811. The other end of the spring Sp abuts against the ball B. The ball B is pressed against the wall portion 82 by the biasing force of the spring Sp, and the through hole 82a provided in the wall portion 82 is sealed by the ball B. An outlet 83a is provided in the center of the support member 83. The outlet 83a connects the space S80 in which the ball B is accommodated and the connection portion 931. A seal ring S is fitted onto the outer periphery of the large diameter portion 812. The seal ring S seals the gap between the outer periphery of the large diameter portion 812 and the inner periphery of the connection port 99.

[0076] In the relief valve 80, when the pressure in the oil passage 23 (oil passage 231) becomes equal to or higher than the reference pressure, the ball B compresses the spring Sp and moves in a direction away from the wall portion 82. This releases the ball B from sealing the through hole 82a, and the oil OL in the oil passage 23 is discharged from the discharge port 83a of the relief valve 80 to the third connection passage 903 on the control valve CV side. As described above, the third connection passage 903 communicates with the oil passage 906 that connects the drain port of the line pressure regulating valve 951 and the discharge port 96 for the oil OL (see FIG. 8). Therefore, the oil OL discharged from the relief valve 80 to the third connecting passage 903 is finally discharged from the outlet 96 of the control valve CV into the second chamber S2 (see FIG. 7).

[0077] As shown in Figure 7, in case 6, connection port 99 of oil passage 23, connection port 97 of oil passage 21 described above, and connection port 98 of oil passage 22 described above are arranged side by side in the vertical direction in the area of ​​wall portion 682 that overlaps with partition portion 62. These connection ports 97, 98, 99 are provided in a positional relationship so as to overlap with the control valve CV. Therefore, almost simultaneously with the installation of the control valve CV in the second chamber S2, the connections between the connection ports 97, 98, 99 and the respective connection paths (901, 902, 903) on the control valve CV side are completed.

[0078] The operation of the hydraulic circuit 20 will now be described. In the hydraulic circuit 20, when the electric oil pump EOP is not driven, the valve body 915 of the check valve 91 seals the opening of the oil passage 211 (see FIG. 10 ). Therefore, the inflow of the oil OL into the oil passage 211 (oil passage 21) on the electric oil pump EOP side is restricted. When the mechanical oil pump MOP is driven in this state, the valve element 925 (see FIG. 11) of the check valve 92 is pushed by the oil OL supplied from the oil passage 22 and displaced in a direction away from the wall portion 682. This unseals the oil passage 22, and the oil OL supplied from the mechanical oil pump MOP side is supplied to the line pressure regulating valve 951 (see FIG. 8) side through the oil passage 22 and the second connection passage 902 inside the control valve CV.

[0079] As described above, the second connection passage 902 merges with the first connection passage 901 inside the hydraulic control circuit 95. Therefore, when the mechanical oil pump MOP is driven, the oil OL also flows into the connection part 911 (see FIG. 10) in which the check valve 91 is provided. Then, the pressure inside the connection part 911 increases due to the inflowing oil. Here, the abutment part 917 of the valve body 915 of the check valve 91 is in metal-to-metal contact with the wall part 682. Therefore, when the pressure inside the connection part 911 increases, the oil OL may flow into the oil passage 21 through the contact interface between the abutment part 917 and the wall part 682. In such a case, the pressure of the oil OL in the oil passage 21 between the check valve 91 and the electric oil pump EOP increases.

[0080] Here, if the electric oil pump EOP to which the oil passage 21 is connected does not have a mechanism for releasing the internal pressure to the outside, when the pressure of the oil OL in the oil passage 21 increases, the pressure of the oil OL in the oil passage 23 will also increase. The oil passage 23 connects the electric oil pump EOP and the strainer 10, and a check valve 18 is provided between the oil passage 23 and the strainer 10 (see FIG. 9). Therefore, a pressure increase in the oil passage 21 caused by the inflow of the oil OL from the control valve CV side causes a pressure increase of the oil OL in the oil passage 23.

[0081] In this embodiment, the oil passage 231 constituting the oil passage 23 has a connection port 99 that opens to the surface of the wall portion 682 on the second chamber S2 side. The relief valve 80 is provided in this connection port 99. Therefore, when the pressure in the oil passage 23 exceeds the reference pressure, the oil OL is discharged from the relief valve 80 to the third connection passage 903 on the control valve CV side. This prevents the oil OL in the oil passage 23 from reaching or exceeding the reference pressure.

[0082] Here, if the connection port 99 is not provided with the relief valve 80 and is closed with a plug, the pressure in the oil passage 23 acts on the check valve 18 on the strainer 10 side. 3, the check valve 18 has the other end 180b side of the cylindrical main body 180 fitted inside the connection part 625 on the partition wall 62 side. A seal ring S fitted onto the outer periphery of the other end 180b of the main body 180 seals the gap between the outer periphery of the main body 180 and the inner periphery of the connection port 625a of the connection part 625.

[0083] When the pressure of the oil OL in the oil passage 23 (oil passage 231) increases, pressure acts on the seal ring S provided on the outer periphery of the other end 180b side of the main body 180. Then, a biasing force acts on the seal ring S toward one end 18a side (right side in the figure) of the main body 180. As a result, the seal ring S may fall off from the recessed groove 181. When the seal ring S falls off to the position shown by the imaginary line in the figure, the gap between the outer periphery of the main body 180 and the inner periphery of the connection port 625a is opened. When the electric oil pump EOP is driven in this state, air may be sucked in through the opened gap.

[0084] As described above, in this embodiment, the oil passage 23 (oil passage 231) is provided with the relief valve 80 that discharges the oil OL in the oil passage 23 to the outside when the pressure in the oil passage 23 exceeds the reference pressure. This reduces the possibility that the excessive pressure will affect the check valve 18 on the strainer 10 side. This reduces the possibility that the sealing performance of the check valve 18 on the strainer 10 side will be affected.

[0085] As described above, the hydraulic circuit 20 according to this embodiment has the following configuration. (1) The hydraulic circuit 20 includes: a first oil passage (oil passage 21, first connection passage 901) communicating with a discharge port 71 of an electric oil pump EOP (first oil pump); a second oil passage (oil passage 22, second connection passage 902) communicating with a discharge port 140 of a mechanical oil pump MOP (second oil pump); a hydraulic control circuit 95 in which a line pressure regulating valve 951 (first pressure regulating valve) is disposed downstream of a junction P of a first oil passage (first connection passage 901) and a second oil passage (second connection passage 902); an oil passage 23 (third oil passage) connecting the suction port 72 of the electric oil pump EOP and the strainer 10; a check valve 18 that is provided in the oil passage 23 and that restricts the movement of the oil OL toward the strainer 10; The oil passage 23 has a relief valve 80 that is provided in the oil passage 23 and that discharges the oil OL in the oil passage 23 to the outside when the pressure in the oil passage 23 exceeds a reference pressure.

[0086] With this configuration, when the pressure in oil passage 23 exceeds the reference pressure, oil OL in oil passage 23 is discharged to the outside through relief valve 80, thereby suppressing pressure rise in the oil passages (oil passage 23, oil passage 21) on the electric oil pump EOP side.

[0087] (2) The hydraulic circuit 20 has a partition wall 62 (support wall) that supports the strainer 10 . The partition wall portion 62 is provided with an oil passage 23 (third oil passage) and a connection port 625a communicating with the oil passage 23. The check valve 18 has a main body portion 180 that functions as a connecting member that is fitted into the connection port 625a to connect the strainer 10 and the oil passage 23. A seal ring S that seals the gap between the inner periphery of the connection port 625a and the outer periphery of the main body 180 is fitted onto the outer periphery of the main body 180.

[0088] If the relief valve 80 is not provided, when the pressure in the oil passage 23 increases, the seal ring S may be turned over by the pressure, causing a gap to form between the outer periphery of the main body 180 and the inner periphery of the connection port 625a. If the electric oil pump EOP is driven in this state, air may be sucked in through the resulting gap, causing the discharge pressure of the electric oil pump EOP to become unstable. As described above, by providing the relief valve 80 in the oil passage 23, the oil OL in the oil passage 23 can be discharged and the pressure in the oil passage 23 can be reduced before the pressure reaches a level that would cause the seal ring S to turn over and create a gap. This reduces the possibility that a gap will occur between the outer periphery of the main body 180 and the inner periphery of the connection port 625a, causing instability in the discharge pressure of the electric oil pump EOP.

[0089] (3) The hydraulic circuit 20 has a control valve CV having a hydraulic control circuit 95 therein. The first oil passage is made up of an oil passage 21 on the partition wall portion 62 side (oil passage on the support wall side) and a first connection passage 901 on the control valve CV side (oil passage on the control valve side). At the connection between the oil passage 21 and the first connection passage 901, a check valve 91 (first check valve) that restricts the movement of the oil OL toward the electric oil pump EOP is provided.

[0090] Since the first oil passage (first connection passage 901) and the second oil passage (second connection passage 902) merge inside the control valve CV, when the mechanical oil pump MOP is driven, the pressure of the oil OL toward the electric oil pump EOP acts on the check valve 91. Therefore, a check valve 91 is provided to restrict the movement of the oil OL toward the electric oil pump EOP side, but if the pressure of the oil OL toward the electric oil pump EOP side increases, there is a possibility that the oil OL will enter the oil passage 21. In such a case, the pressure on the electric oil pump EOP side becomes higher than that of the check valve 91. As described above, the relief valve 80 is provided in the oil passage 23 connected to the suction port 72 of the electric oil pump EOP, so that the pressure on the oil passage 23 side can be prevented from becoming higher than the reference pressure.

[0091] (4) The partition portion 62 (support wall) has a wall portion 682 (partition wall) that separates the first chamber S1 in which the strainer 10 is disposed and the second chamber S2 in which the control valve CV is disposed. The control valve CV is mounted in the wall 682 . The oil passage 21 on the partition wall portion 62 (support wall portion) side opens into a portion of the wall portion 682 facing the control valve CV.

[0092] With this configuration, the oil passage 21 on the wall portion 682 side and the first connection passage 901 on the control valve CV side can be connected in the shortest distance. Also, since the oil passage 21 opens to the joint surface of the wall portion 682 with the control valve CV, leakage of oil OL from the connection portion between the oil passage 21 and the first connection passage 901 can be suppressed.

[0093] (5) The check valve 91 has a valve body 915 having a contact portion 917 with a diameter larger than the opening diameter (inner diameter D211) of the oil passage 211 on the partition portion 62 side. The valve body 915 is displaceable in the direction of the axis X91 along the opening direction of the oil passage 21 (oil passage 211).

[0094] The contact portion 917 of the valve body 915 comes into metal-to-metal contact with the periphery surrounding the opening of the oil passage 211 in the wall portion 682 , thereby blocking communication between the oil passage 21 (oil passage 211 ) and the first connection passage 901 . Therefore, when the pressure on the first connection passage 901 side increases, there is a possibility that oil OL will flow into the oil passage 21 (oil passage 211) through the contact interface between the abutment portion 917 and the wall portion 682. In such a case, the pressure rises not only in the oil passage 21 between the check valve 91 and the electric oil pump EOP, but also in the oil passage 23 connecting the electric oil pump EOP and the strainer 10. As described above, when the pressure in the oil passage 23 exceeds the reference pressure, the relief valve 80 discharges the oil OL in the oil passage 23 to the outside, thereby preventing the pressure in the oil passages 21, 23 from rising above the reference pressure. Thus, by setting the reference pressure to a pressure lower than the pressure at which the seal ring S of the check valve 18 turns over and creates a gap, it is possible to reduce the possibility that the pressure in the oil passages 21, 23 will become too high and create a gap between the outer periphery of the main body 180 of the check valve 18 and the inner periphery of the connection port 625a.

[0095] (6) The oil passage 23 (third oil passage) has a region on the wall portion 682 side from the intersection of the oil passage 231 and the oil passage 232, which becomes a branch passage 231' that opens to the surface of the wall portion 682 (partition wall) on the second chamber S2 side. The relief valve 80 is provided in the region of the branch passage 231 ′ of the oil passage 231 .

[0096] With this configuration, by inserting the relief valve 80 into the branch passage 231' that opens into the second chamber S2, the relief valve 80 can be disposed without impeding the movement of the oil OL between the strainer 10 and the electric oil pump EOP.

[0097] (7) The outlet port 83a of the relief valve 80 is connected to an oil passage 906 that constitutes a drain circuit via a third connection passage 903 in the control valve CV.

[0098] The oil OL discharged from the discharge port 83a is used to take in the oil OL from the strainer 10. Therefore, the drain port 96 of the oil OL in the drain circuit is opened at a position suitable for the oil OL to return to the strainer 10. Therefore, by connecting the drain port 83a of the relief valve 80 to the drain circuit, the oil OL discharged from the relief valve 80 can be discharged to a position suitable for the oil OL to return to the strainer 10. As a result, when the hydraulic circuit 20 is used in a power transmission device 1 for a vehicle, the amount of oil OL stored in the housing HS of the power transmission device 1 can be reduced. Therefore, improvements in fuel efficiency and electricity consumption of a vehicle equipped with the power transmission device 1 can be expected.

[0099] (I) The second oil passage is made up of the oil passage 22 on the partition wall portion 62 (support wall) side and the second connection passage 902 on the control valve CV side. At the connection between the oil passage 22 and the second connection passage 902, a check valve 92 (second check valve) is provided to restrict the movement of the oil OL toward the mechanical oil pump MOP. The check valve 92 has a valve body 925 having a contact portion 927 with a diameter larger than the opening of the oil passage 22 that opens into the wall portion 682 . The valve body 925 is displaceable in the direction of the axis X92 along the opening direction of the oil passage 22.

[0100] The contact portion 927 of the valve body 925 comes into metal-to-metal contact with the periphery surrounding the opening of the oil passage 22 in the wall portion 682 , thereby blocking communication between the oil passage 22 and the second connection passage 902 . Therefore, even if the electric oil pump EOP is driven while the mechanical oil pump MOP is not driven, the oil OL that has flowed from the first connection passage 901 side into the second connection passage 902 can be prevented from flowing into the oil passage 22.

[0101] (II) When viewed from the vehicle front side of the power transmission device 1, the connection port 97 of oil passage 21, the connection port 98 of oil passage 22, and the connection port 99 of oil passage 23 are arranged in a vertical line in the area of ​​wall portion 682 that overlaps with partition portion 62 (see Figure 7). In the wall portion 682, the connection ports 97, 98, and 99 are disposed in a positional relationship in which they overlap the control valve CV.

[0102] The area of ​​wall 682 that overlaps with partition 62 is an area of ​​high rigidity in case 6. By opening connection ports 97, 98 in this area, stability can be ensured when valve bodies 915, 925 are brought into contact with the periphery of the opening of connection ports 97, 98. This allows the opening of connection ports 97, 98 to be reliably closed by valve bodies 915, 925. Furthermore, the installation of the control valve CV in the second chamber S2 and the connection of each connection path on the control valve CV side (the first connection path 901, the second connection path 902, the third connection path 903) to the connection ports 97, 98, 99 can be completed simultaneously.

[0103] In the above-described embodiment, the connection port 99 on the base end side of the oil passage 231 is open at a position opposite the control valve CV, and the oil OL discharged from the relief valve 80 provided in the connection port 99 is discharged to the third connection passage 903 on the control valve CV side. The oil OL discharged from the relief valve 80 may be discharged directly into the second chamber S2 that houses the control valve CV, or into the first chamber S1.

[0104] In the above-described embodiment, as shown in FIG. 7, when viewed from the vehicle front side of the power transmission device 1, the connection port 97 of the oil passage 21, the connection port 98 of the oil passage 22, and the connection port 99 of the oil passage 23 are arranged side by side in the vertical direction in the area of ​​the wall portion 682 that overlaps with the partition portion 62. These connection ports 97, 98, 99 do not necessarily need to be arranged side by side in the vertical direction in the region overlapping with the partition wall portion 62. They can be appropriately changed according to the arrangement of the connection passages on the control valve CV side.

[0105] In the above embodiment, the power transmission device 1 transmits the rotation of the engine ENG to the drive wheels WH, WH, but the power transmission device 1 may transmit the rotation of at least one of the engine ENG and a motor (rotating electric machine) to the drive wheels WH, WH. For example, the power transmission device 1 may be of a one-motor, two-clutch type (a type in which a motor is disposed between the engine ENG and the power transmission device, a first clutch is disposed between the engine ENG and the motor, and a second clutch is disposed within the power transmission device 1). In the above embodiment, the power transmission device 1 has a speed change function, but the power transmission device may not have a speed change function and may simply decelerate (or may increase) the speed. In the case where the power transmission device does not have a speed change function and is configured to reduce the speed of the motor and transmit the rotation to the drive wheels WH, WH, a hydraulic control circuit for supplying oil OL for cooling the motor and oil OL for lubricating the reduction mechanism is disposed in the second chamber S2 together with the electric oil pump EOP. In the above embodiment, the control unit of the power transmission device 1 has a control valve CV, but in the case where the power transmission device 1 does not have a speed change mechanism and the drive source is a motor (rotary electric) instead of an engine ENG, the control unit may have an inverter or the like for driving and controlling the motor. The present invention can be applied to things other than vehicles.

[0106] Although the embodiment of the present invention has been described above, the above embodiment is merely one application example of the present invention, and the technical scope of the present invention is not limited to the specific configuration of the above embodiment. Appropriate modifications are possible within the scope of the technical concept of the invention. [Explanation of symbols]

[0107] 6: Case 10: Strainer 18: Check valve 20: Hydraulic circuit 21: Oil passage (1st oil passage: Oil passage on the support wall side) 22: Oil road (2nd oil road) 23: Oil road (3rd oil road) 62: Partition wall (support wall) 71:Discharge port 72: Intake port 80: Relief valve 91: Check valve (first check valve) 95: Hydraulic control circuit 99: Connection port (relief valve outlet) 140:Discharge port 180: Main body (connecting member) 211: Oil passage (2nd oil passage: Oil passage on the support wall side) 212: Oil road (1st oil road) 231: Oil road (3rd oil road) 231: Branch road (third oil route) 232: Oil road (3rd oil road) 625a: Connection port 682: Wall (compartment wall) 901: First connection passage (first oil passage: oil passage on the control valve side) 902: Second connection passage (second oil passage) 906: Oil passage (drain circuit) 917: Contact part 951: Line pressure regulator (first regulator) CV: Control valve EOP: Electric oil pump (first oil pump) MOP: Mechanical oil pump (second oil pump) OL: Oil P: Confluence point S: Seal ring S1: Room 1 S2: 2nd room

Claims

1. a first oil passage communicating with a discharge port of the first oil pump; a second oil passage communicating with a discharge port of the second oil pump; a hydraulic control circuit in which a first pressure regulating valve is disposed downstream of a junction of the first oil passage and the second oil passage; a third oil passage connecting a suction port of the first oil pump and a strainer; A hydraulic circuit having a check valve provided in the third oil passage and restricting movement of oil toward the strainer, a hydraulic circuit having a relief valve provided in the third oil passage and configured to discharge oil in the third oil passage to the outside when the pressure in the third oil passage exceeds a reference pressure.

2. In claim 1, A support wall is provided to support the strainer. The support wall is provided with the third oil passage and a connection port communicating with the third oil passage, The check valve has a connection member that is fitted into the connection port to connect the strainer and the third oil passage, A hydraulic circuit, wherein a seal ring is fitted onto the outer periphery of the connection member to seal a gap between the outer periphery of the connection port and the inner periphery of the connection member.

3. In claim 2, A control valve having the hydraulic control circuit therein, The first oil passage is composed of an oil passage on the support wall side and an oil passage on the control valve side, a first check valve is provided at a connection between the oil passage on the support wall side and the oil passage on the control valve side, the hydraulic circuit;

4. In claim 3, the support wall has a partition wall that partitions a first chamber in which the strainer is disposed and a second chamber in which the control valve is disposed, The control valve is attached to the partition wall, A hydraulic circuit, wherein the oil passage on the support wall side opens to a portion of the partition wall facing the control valve.

5. In claim 4, the first check valve has a valve body having a diameter larger than an opening diameter of the oil passage on the support wall side, The valve body is displaceable in a direction toward an opening of the oil passage on the support wall side.

6. In claim 4, The third oil passage has a branch passage that opens into the partition wall, The relief valve is provided in the branch path.

7. In any one of claims 1 to 6, The outlet of the relief valve is connected to a drain circuit.

Images