Oil pressure circuit

Abstract

The present invention addresses the problem of suppressing a pressure increase in a hydraulic circuit. In order to solve the problem, a hydraulic circuit is provided with: a first oil passage that communicates with a discharge port of a 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 confluence point 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 filter; a check valve that is provided in the third oil passage and that restricts the movement of oil to the filter side; and a relief valve that is provided in the third oil passage and discharges oil in the third oil passage to the outside when the pressure in the third oil passage exceeds a reference pressure.

Description

Technical Field

[0001] The invention relates to an oil pressure circuit. Background Art

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

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-165516 SUMMARY OF THE INVENTION

[0006] In the hydraulic oil supply device, the mechanical oil pump and the electric oil pump pressurize the oil sucked in through the filter. 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.

[0007] The discharge port of the mechanical oil pump is connected to the hydraulic control device via a first suction pipe. The first suction pipe is connected to a second suction pipe connected to the discharge port of the electric oil pump.

[0008] Check valves for preventing oil from flowing back to the mechanical oil pump and the electric oil pump are provided in the first suction pipe and the second suction pipe, respectively.

[0009] Problems to be solved by the invention

[0010] In such a hydraulic oil supply device, when the mechanical oil pump (mechanical oil pump) is driven and the pressure in the first suction pipe increases, oil (hydraulic oil) may leak from the check valve to the electric oil pump (electric oil pump) side.

[0011] When the electric oil pump does not have a mechanism for releasing pressure, the pressure in the circuit connecting the electric oil pump and the filter will rise. In this way, a gap will be generated in the sealing portion provided at the connection portion with the circuit, and leakage of the working oil may occur.

[0012] Therefore, in such a drive device (power transmission device) including two pumps, it is required to suppress the pressure increase in the hydraulic circuit. Summary of the invention

[0014] A hydraulic circuit according to one aspect of the present invention comprises:

[0015] a first oil passage, which is in communication with a discharge port of the first oil pump;

[0016] a second oil passage, which is in communication with a discharge port of a second oil pump;

[0017] an oil pressure control circuit, wherein a first pressure regulating valve is arranged downstream of a confluence point of the first oil circuit and the second oil circuit;

[0018] a third oil circuit, which connects the suction port of the first oil pump and the filter;

[0019] a check valve, which is provided in the third oil passage and restricts the movement of oil toward the filter side,

[0020] in,

[0021] The oil pressure circuit also has:

[0022] The relief valve is provided in the third oil passage and discharges the oil in the third oil passage to the outside when the pressure in the third oil passage exceeds a reference pressure.

[0023] Effects of the Invention

[0024] According to one aspect of the present invention, it is possible to suppress a pressure increase in the hydraulic circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram showing a schematic structure of a power transmission device.

[0026] Figure 2 This is a diagram of the housing as viewed from the second cover side.

[0027] Figure 3 is a schematic representation of the Figure 2 A cross-sectional view of the housing cut along line AA.

[0028] Figure 4 is a schematic representation of the Figure 3 The cross-section of the shell is shown along line AA.

[0029] Figure 5 This is a perspective view of the filter viewed from above the upper case side.

[0030] Figure 6 It is a diagram for explaining the supporting structure of the mechanical oil pump of the partition wall portion.

[0031] Figure 7 This is a diagram showing the storage portion as viewed from the front side of the vehicle.

[0032] Figure 8 This is a schematic diagram of the hydraulic circuit.

[0033] Fig. 9 This is a diagram schematically showing a cross section of the casing in order to explain the third oil passage.

[0034] Fig.10 This is a diagram schematically showing a cross section of the casing in order to explain the first oil passage.

[0035] Fig.11 This is a diagram schematically showing a cross section of the casing in order to explain the second oil passage. DETAILED DESCRIPTION

[0036] First, the definitions of terms used in this specification are explained.

[0037] The power transmission device is a device having 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 speed reduction mechanism.

[0038] In the following embodiments, an example is given in which the power transmission device has a function of transmitting the output rotation of the engine, but the power transmission device may be any device as long as it transmits the output rotation of at least one of the engine and the electric motor (rotating electric machine).

[0039] “Axial direction” refers to the axial direction of the rotation axis of a component constituting the power transmission device. “Radial direction” refers to the direction orthogonal to the rotation axis of a component constituting the power transmission device. Examples of the component are a motor, a gear mechanism, a differential gear mechanism, and the like.

[0040] The "vertical arrangement" of the control valve means that, in the case of a control valve having a basic structure in which a partition is sandwiched between valve bodies, the valve bodies of the control valve are stacked in a horizontal direction based on the state in which the power transmission device is installed on the vehicle. Here, "horizontal direction" does not mean a strictly horizontal direction, but also includes a case where the stacking direction is inclined relative to the horizontal line.

[0041] Furthermore, “vertical arrangement” of the control valve refers to arranging the control valve in such a direction that a plurality of pressure regulating valves in the control valve are aligned in the direction of a vertical line VL based on a state in which the power transmission device is installed on a vehicle.

[0042] "Arranging a plurality of pressure regulating valves in the direction of the vertical line VL" means that the pressure regulating valves in the control valve are arranged at positions staggered in the direction of the vertical line VL. In this case, the plurality of pressure regulating valves do not need to be arranged at positions completely staggered in the direction of the vertical line VL. This also includes the case where each pressure regulating valve has a range that partially overlaps with other pressure regulating valves when viewed from the horizontal line direction and is arranged in the direction of the vertical line VL.

[0043] Hereinafter, a case where an embodiment of a hydraulic circuit according to the present invention is applied to a hydraulic circuit of a power transmission device for a vehicle will be described as an example.

[0044] Figure 1 1 is a schematic diagram for explaining a schematic structure of a power transmission device 1 mounted on a vehicle V. FIG.

[0045] like Figure 1As shown, the 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 .

[0046] The housing HS contains the torque converter T / C, the forward / reverse switching mechanism 2, the speed change mechanism 3, the speed reduction mechanism 4, the differential device 5, the electric oil pump EOP, the mechanical oil pump MOP, the control valve CV, the filter 10 and the like.

[0047] Here, the torque converter T / C, the forward / reverse switching mechanism 2, the speed change mechanism 3, the speed reduction mechanism 4, and the differential device 5 are components of the power transmission mechanism.

[0048] In the power transmission device 1 , the output rotation of the engine ENG (driving source) is input to the forward / reverse travel switching mechanism 2 via the torque converter T / C.

[0049] The rotation input to the forward / reverse travel switching mechanism 2 is input to the primary pulley 31 of the speed change mechanism 3 in the form of clockwise rotation or counterclockwise rotation.

[0050] In the speed change mechanism 3 , by changing the winding radius of the belt 30 on the primary pulley 31 and the secondary pulley 32 , the rotation input to the primary pulley 31 is speed-changed at a desired speed ratio and then output from the output shaft 33 of the secondary pulley 32 .

[0051] The output rotation of the secondary pulley 32 is input to the differential device 5 (differential gear mechanism) via the speed reduction mechanism 4 , and then transmitted to the drive wheels WH, WH via the left and right drive shafts 55A, 55B.

[0052] The speed reduction mechanism 4 includes an output gear 41 , an idler gear 42 , a speed reduction gear 43 , and a final gear 45 .

[0053] The output gear 41 rotates integrally with the output shaft 33 of the secondary pulley 32 .

[0054] The idler gear 42 is meshed with the output gear 41 so as to transmit rotation. The idler gear 42 rotates integrally with the idler shaft 44. The idler shaft 44 is provided with a reduction gear 43 having a smaller diameter than the idler gear 42. The reduction gear 43 is meshed with a final gear 45 fixed to the outer periphery of the differential case 50 of the differential device 5 so as to transmit rotation.

[0055] 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 coaxially (concentrically) arranged on the rotation axis X1 (first axis) of the primary pulley 31 .

[0056] The output shaft 33 of the secondary pulley 32 and the output gear 41 are coaxially arranged on the rotation axis X2 (second axis) of the secondary pulley 32 .

[0057] The idler gear 42 and the reduction gear 43 are coaxially arranged on a common rotation axis X3.

[0058] The final gear 45 and the drive shafts 55A and 55B are coaxially arranged on a common rotation axis X4. In the power transmission device 1, these rotation axes X1 to X4 are set to be parallel to each other. Hereinafter, these rotation axes X1 to X4 are also collectively referred to as the rotation axis X of the power transmission device 1 (power transmission mechanism) as needed.

[0059] Figure 2 This is a schematic diagram showing a state where the housing 6 is viewed from the second cover 8 side.

[0060] In addition, Figure 2 In the enlarged view of FIG. 1 , the filter 10 and the mechanical oil pump MOP are omitted, and the connection parts 625 and 627 provided in the partition wall part 62 are shown. Figure 2 In the enlarged view of FIG. 6 , in order to facilitate the determination of the position of the opening 620 , the area of ​​the opening 620 is marked with cross hatching lines.

[0061] like Figure 2 As shown, the housing 6 has a cylindrical peripheral wall portion 61 and a partition wall portion 62 .

[0062] like Figure 1 As shown, the partition wall 62 divides the space inside the peripheral wall 61 into two in the direction of the rotation axis X1. One side of the partition wall 62 in the direction of the rotation axis X1 is the first chamber S1, and the other side is the third chamber S3.

[0063] In the housing 6, the opening of the first chamber S1 is sealed by the second cover 8 (torque converter cover), thereby forming a closed first chamber S1. The opening of the third chamber S3 is sealed by the first cover 7 (side cover), thereby forming a closed third chamber S3.

[0064] The first chamber S1 accommodates the forward / reverse switching mechanism 2, the speed reduction mechanism 4, and the differential device 5. The speed change mechanism 3 is accommodated in the third chamber S3.

[0065] The housing 6 has a storage portion 68 forming the second chamber S2 on the outer periphery of the peripheral wall portion 61 on the vehicle front side. The storage portion 68 is provided with an opening toward the vehicle front side. The opening of the storage portion 68 is sealed by the third cover 9, thereby forming a closed second chamber S2.

[0066] A control valve CV and an electric oil pump EOP are arranged in the second chamber S2.

[0067] like Figure 1 As shown in FIG. 1 , the control valve CV has a basic structure in which a partition plate 940 is sandwiched between valve bodies 941, 941. A hydraulic control circuit 95 (see FIG. 1 ) described later is formed inside the control valve CV. Figure 8The hydraulic control circuit 95 includes a solenoid driven based on a command from a control device (not shown), a pressure regulating valve SP (spool valve) actuated by a signal pressure generated by the solenoid, and an oil passage.

[0068] like Figure 2 As shown, the partition wall portion 62 of the case 6 is provided in a range that crosses the rotation axis (rotation axis X1 to rotation axis X4) of the power transmission mechanism. The partition wall portion 62 is provided in a direction that is substantially orthogonal to the rotation axis (rotation axis X1 to rotation axis X4).

[0069] The partition wall portion 62 is provided with through holes 621 , 622 , 624 and a support hole 623 .

[0070] The through hole 621 is formed around the rotation axis X1. Figure 1 ) is rotatably supported by a supporting wall portion 631 surrounding the through hole 621.

[0071] A piston (not shown) and friction plates (forward clutch, reverse brake) of the forward / reverse switching mechanism 2 are accommodated inside the peripheral wall portion 641 surrounding the support wall portion 631 .

[0072] The through hole 622 is formed with the rotation axis X2 as the center.

[0073] The output shaft 33 (see Figure 1 ) is rotatably supported by a peripheral wall portion 632 surrounding the through hole 622.

[0074] The support hole 623 is a bottomed hole formed around the rotation axis X3.

[0075] Idler shaft 44 (refer to Figure 1 ) is rotatably supported by a peripheral wall portion 633 surrounding the support hole 623.

[0076] The through hole 624 is formed with the rotation axis X4 as the center.

[0077] The differential case 50 of the differential device 5 (see Figure 1 ) is rotatably supported by a supporting wall portion 634 surrounding the through hole 624.

[0078] In this way, the partition wall portion 62 functions as a support wall for the input shaft 34 of the primary pulley 31 , the output shaft 33 of the secondary pulley 32 , the idler shaft 44 , and the differential case 50 .

[0079] In the case 6 , a region on the vehicle front side relative to the support wall portion 634 and a region below the peripheral wall portion 641 serves as a housing portion 67 for the filter 10 and the mechanical oil pump MOP.

[0080] The storage portion 67 is located at the lower portion of the housing 6 (housing HS). Therefore, in the storage portion 67, oil OL for driving and cooling the components of the power transmission mechanism is stored.

[0081] Figure 3 is a schematic representation of the Figure 2 The cross-section of the housing HS is shown in FIG. Figure 3 , the connection method between the filter 10 and the partition wall portion 62 is shown.

[0082] like Figure 3 As shown, the storage portion 67 is open toward the first chamber S1 side ( Figure 3 In the lower part of the housing 6, a storage portion 67 is formed in a range that crosses the lower part of the peripheral wall portion 641 that stores the forward / reverse travel switching mechanism 2 in the direction of the rotation axis X1 of the power transmission device 1.

[0083] An opening 620 that penetrates the partition wall 62 in the direction of the rotation axis X1 is formed at the lower portion of the partition wall 62. The first chamber S1 and the third chamber S3 in the housing 6 communicate with each other through the opening 620.

[0084] The housing portion 67 has a connection portion 625 of the filter 10 provided below the peripheral wall portion 641. The connection portion 625 is a cylindrical portion with a connection port 625a facing the second cover 8 (first chamber S1). The oil passage 231 is opened inside the connection portion 625.

[0085] like Figure 2 As shown, the oil passage 231 extends linearly in the partition wall 62 in a direction away from the opening 620. The oil passage 231 passes through the oil passage 232 in the housing 6 (see Fig. 9 ) is connected to the electric oil pump EOP housed in the housing portion 68. Here, the oil passage 231 and the oil passage 232 constitute a third oil passage described later.

[0086] like Figure 2 As shown, in the housing portion 67, a connection portion 627 for the mechanical oil pump MOP is provided on the lower side of the oil passage 231. The 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 communicates with the oil passage 22 provided in the partition wall portion 62.

[0087] The oil passage 22 extends along the oil passage 231 below the oil passage 231 toward the housing portion 68 (right side in the figure). The oil passage 22 is connected to the control valve CV (see FIG. 1 ) provided in the housing portion 68. Fig.11 Here, the oil passage 22 constitutes a second oil passage on the housing 6 side described later.

[0088] Figure 4is a schematic representation of the Figure 3 The cross-section of the housing HS is shown in FIG. Figure 4 , the arrangement of the filter 10 and the mechanical oil pump MOP in the housing portion 67 is schematically shown.

[0089] Figure 5 This is a perspective view of the filter 10 as viewed from above the upper case 11 side.

[0090] like Figure 3 and Figure 4 As shown, the filter 10 has a basic structure in which a filter 19 is arranged in a space S10 formed between an upper case 11 and a lower case 12 .

[0091] like Figure 5 As shown in FIG. 1 , a first connection portion 15 is provided on one side portion 11a of the upper housing 11. The first connection portion 15 is a tubular member having an oil discharge passage 151 inside. A second connection portion 16 is provided on the root side of the first connection portion 15. Figure 3 As shown, the second connection portion 16 is formed in a bottomed cylindrical shape having a discharge path 161 for the oil OL inside.

[0092] 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 and 161 are orthogonal to each other.

[0093] The discharge path 161 in the second connection portion 16 and the discharge path 151 in the first connection portion 15 communicate with the space S10 inside the filter 10 .

[0094] like Figure 5 As shown in FIG. 1 , in the upper housing 11, a recess 17 is provided in the region located on the extension line of the discharge path 161 in the second connection portion 16, which is recessed toward the lower housing 12. Figure 3 As shown, the check valve 18 can be inserted into the discharge path 161 from the side of the filter 10 without interfering with the upper case 11 .

[0095] like Figure 3 As shown, the check valve 18 includes a cylindrical body portion 180 and a valve element 186 .

[0096] The main body 180 has one end 180a in the longitudinal direction fitted inside the exhaust passage 161 on the filter 10 side. The main body 180 has the other end 180b in the longitudinal direction fitted inside the connection portion 625 on the partition wall 62 side.

[0097] Grooves 181, 181 are provided on the outer periphery of one end 180a side and the outer periphery of the other end 180b side of the main body 180. Seal rings S, S are respectively fitted externally in the grooves 181, 181. 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 portion 625.

[0098] The main body 180 of the check valve 18 also functions as a connection member that connects the filter 10 and the connection portion 625 on the partition wall portion 62 side.

[0099] The valve element 186 is provided inside the body 180 so as to be displaceable along the axis X18 (left-right direction in the figure). The axis X18 is a straight line along the length direction of the body 180. The axis X18 is also a straight line along the assembly direction of the filter 10 with respect to the partition wall 62.

[0100] The main body 180 is provided with an annular wall portion 182 at one end portion 180a in the longitudinal direction. A through hole 182a penetrating the wall portion 182 in the thickness direction is provided at the center of the wall portion 182.

[0101] The main body 180 is provided with a support cylinder 183 at the other end 180b in the longitudinal direction. The support cylinder 183 is arranged concentrically with the main body 180. The support cylinder 183 is supported by a support beam 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 around the axis X18 of the main body 180. An opening 185 through which the oil OL can pass is formed between the support beams 184, 184 adjacent to each other in the circumferential direction around the axis X18.

[0102] The shaft portion 187 of the valve core 186 is inserted into the support cylinder 183 from the axis X18 direction.

[0103] The valve core 186 is provided with an abutment portion 188 having a larger diameter than the shaft portion 187 at one end of the shaft portion 187. A spring Sp is externally inserted on the shaft portion 187. One end of the spring Sp abuts against the abutment portion 188 from the axis X18 direction. The other end of the spring Sp abuts against the support cylinder 183 from the axis X18 direction. The spring Sp is positioned by the support cylinder 183. The spring Sp applies force to the abutment portion 188 of the valve core 186 toward the wall portion 182 side (the right side in the figure). The abutment portion 188 of the valve core 186 abuts against the wall portion 182 under the force of the spring Sp. The through hole 182a in the center of the wall portion 182 is closed by the abutment portion 188.

[0104] In the power transmission device 1, when the electric oil pump EOP is driven, the oil stored in the lower part of the housing HS is sucked in through the filter 10. The valve core 186 is displaced in a direction away from the wall portion 182 by the negative pressure generated by the driving of the electric oil pump EOP. As a result, the seal of the through hole 182a is released, and the oil OL sucked in through the filter 10 is sucked into the oil path 231 through the through hole 182a. Then, the sucked oil OL is finally supplied to the electric oil pump EOP.

[0105] like Figure 4 As shown, the filter 10 is assembled to the mechanical oil pump MOP by inserting the front end 15a of the first connection portion 15 into the connection port 120 on the mechanical oil pump MOP side. The mechanical oil pump MOP is assembled to the partition wall portion 62, and the filter 10 is supported by the partition wall portion 62 via the mechanical oil pump MOP.

[0106] Figure 6 62 is a diagram for explaining the support structure of the mechanical oil pump MOP in the partition wall portion 62. Figure 6 Schematically shows the Figure 4 The cross section after the AA line cuts off the mechanical oil pump MOP.

[0107] like Figure 6 As shown, a positioning projection 150 and an oil OL discharge port 140 are provided at a portion of the mechanical oil pump MOP that faces the partition wall portion 62 .

[0108] The partition wall portion 62 has an insertion hole 630 and a connection portion 627 opened on a surface facing the mechanical oil pump MOP.

[0109] 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 bolts (not shown).

[0110] When the mechanical oil pump MOP is fixed to the partition wall 62, the discharge port 140 of the mechanical oil pump MOP is arranged at a position opposite to the connection portion 627 on the partition wall 62 side, and the discharge port 140 is connected to the connection portion 627. The connection portion 627 is connected to the oil path 22 in the partition wall 62. Therefore, the oil OL discharged from the discharge port 140 of the mechanical oil pump MOP is supplied to the oil path 22 through the connection portion 627. The oil OL supplied to the oil path 22 is supplied to the control valve CV in the storage portion 68 (refer to Fig.11 ).

[0111] When the mechanical oil pump MOP is fixed to the partition wall portion 62 , substantially simultaneously, the second connection portion 16 of the filter 10 is connected to the connection portion 625 on the partition wall portion 62 side via the check valve 18 .

[0112] In this state, the first connection portion 15 of the filter 10 is supported by the mechanical oil pump MOP, and the second connection portion 16 is attached to the partition wall portion 62 via the check valve 18 (main body portion 180 ) inserted into the second connection portion 16 .

[0113] Figure 7 This is a view of the storage portion 68 as viewed from the front side of the vehicle. Figure 7 , the second chamber S2 viewed from the front side of the vehicle is schematically shown together with other structural elements of the housing HS (housing 6, first cover 7, second cover 8). In addition, the area of ​​the joint 683 located on the front side of the paper is indicated by cross hatching. In addition, the appearance of the control valve CV and the appearance of the electric oil pump EOP are schematically shown.

[0114] like Figure 7 As shown in FIG. 1 , when viewed from the front side of the vehicle, the storage portion 68 has a peripheral wall portion 681 that surrounds the outer periphery of the second chamber S2 over the entire periphery. The area of ​​the inner wall portion 682 of the peripheral wall portion 681 that overlaps with the first chamber S1 also serves as a partition wall that divides the second chamber S2 and the first chamber S1. The end surface of the peripheral wall portion 681 on the front side of the paper surface serves as a joint portion 683 with the third cover 9.

[0115] like Figure 1 As shown, the housing portion 68 is provided along the rotation axis X of the power transmission device 1. The housing portion 68 is formed to have a range extending from a region adjacent to the peripheral wall portion 61 of the case 6 to the side of the first cover 7 in the rotation axis X direction (left-right direction in the figure).

[0116] In the housing portion 68 (second chamber S2 ), the control valve CV is longitudinally provided such that the stacking direction of the valve bodies 941 , 941 is along the front-rear direction of the vehicle (the up-down direction of the paper).

[0117] Therefore, if Figure 7 As shown, in the second chamber S2, the control valve CV is longitudinally arranged in a manner to satisfy the following conditions: (a) a plurality of pressure regulating valves SP (sliding valves) in the control valve CV are arranged in the direction of a vertical line VL (up and down direction) based on the state in which the power transmission device 1 is installed on the vehicle V; and (b) the forward and backward movement direction Xp of the pressure regulating valve SP (sliding valve) is along the horizontal line direction.

[0118] Thus, the control valve CV is disposed longitudinally in the second chamber S2 without hindering the forward and backward movement of the pressure regulating valve SP (spool valve). Therefore, the second chamber S2 is not enlarged in the vehicle front-rear direction.

[0119] like Figure 7 As shown in FIG. 1 , the control valve CV is provided with a discharge port 96 for the oil OL. The oil OL discharged from each pressure regulating valve SP is discharged from the discharge port 96 .

[0120] Therefore, the oil OL discharged from the discharge port 96 is stored in the second chamber S2 that accommodates the control valve CV.

[0121] In the second chamber S2, a communication hole 94 is opened at the lower portion of the region of the wall portion 682 overlapping with the first chamber S1. In addition, an opening 950 is provided at the upper portion of the region of the wall portion 682 overlapping with the first chamber S1.

[0122] The communication hole 94 and the opening 950 communicate with each other in the first chamber S1 and the second chamber S2 , respectively. Therefore, the oil OL in the second chamber S2 returns to the first chamber S1 through the communication hole 94 .

[0123] In the second chamber S2, the control valve CV and the electric oil pump EOP are arranged along the direction of the rotation axis X ( Figure 7 When viewed from the front side of the vehicle, the control valve CV is arranged in a positional relationship overlapping with the first chamber S1. When viewed from the front side of the vehicle, the electric oil pump EOP is arranged in a positional relationship overlapping with the third chamber S3.

[0124] The electric oil pump EOP has a discharge port 71 for the oil OL and a suction port 72 for the oil OL at a portion facing the wall portion 682 on the back side of the paper.

[0125] The suction port 72 is connected to the oil passage 23 (see Fig. 9 ) is connected to the connection portion 625 of the filter 10.

[0126] The discharge port 71 is connected to the oil passage 21 (see Fig.10 ) is connected to the connection port 97 of the control valve CV.

[0127] Figure 8 It is a schematic configuration diagram of the hydraulic circuit 20 of the power transmission device 1 .

[0128] Fig. 9 2 is a diagram schematically showing a cross section of the housing HS for explaining the third oil passage. Fig. 9 Equivalent to along Figure 2 The cross section of the shell HS is cut along line BB.

[0129] Fig.10 1 is a diagram schematically showing a cross section of the housing HS for explaining the first oil passage. Fig.10 Equivalent to Figure 2 The cross section of the shell HS is cut along the CC line.

[0130] Fig.11 2 is a diagram schematically showing a cross section of the housing HS for explaining the second oil passage. Fig.11 Equivalent to following Figure 2The cross section of the housing HS is cut along the DD line.

[0131] like Figure 8 As shown, the hydraulic circuit 20 of the power transmission device 1 is provided with a mechanical oil pump MOP and an electric oil pump EOP. These oil pumps (mechanical oil pump MOP and electric oil pump EOP) suck the oil OL stored in the lower part of the housing HS (first chamber S1, third chamber S3) through a common filter 10. The sucked oil OL is pressurized and supplied to the hydraulic control circuit 95 in the control valve CV.

[0132] In the following description, when the mechanical oil pump MOP and the electric oil pump EOP are not particularly distinguished, they are simply referred to as “oil pump OP”.

[0133] The hydraulic circuit 20 further includes a first oil circuit (oil circuit 21, first connecting passage 901), a second oil circuit (oil circuit 22, second connecting passage 902), a third oil circuit (oil circuit 23, third connecting passage 903), and a hydraulic control circuit 95. The first oil circuit and the second oil circuit merge at a confluence point P in the control valve CV.

[0134] like Figure 8 As shown, the first oil passage is composed of the oil passage 21 on the case 6 side (the wall portion 682 and the partition wall portion 62 ) and the first connecting passage 901 on the control valve CV side.

[0135] 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 to the control valve CV.

[0136] like Fig.10 As shown, the oil passage 21 is composed of an oil passage 211 extending linearly in the partition wall portion 62 and an oil passage 212 extending linearly in the wall portion 682 .

[0137] 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 serves as a connection port 97 that opens to the second chamber S2.

[0138] 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 .

[0139] The base end 212 a of the oil passage 212 is sealed by the plug PL. The front end 212 b of the oil passage 212 intersects with the oil passage 211 in the partition wall portion 62 .

[0140] Here, the blind hole refers to a hole that is blocked at the front and has an open base end but no open front end.

[0141] In the control valve CV, a connection portion 911 of the first connection passage 901 opens at a portion of the oil passage 211 that faces the connection port 97 .

[0142] The connection portion 911 is a bottomed hole formed with its 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.

[0143] The connecting portion 911 is provided with a valve body 915. 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.

[0144] 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 the axis X91 along the opening direction of the oil passage 211 .

[0145] A spring Sp is externally inserted into the support portion 912 and the shaft portion 916. The valve element 915 is urged toward the wall portion 682 by the urging force of the spring Sp.

[0146] The contact portion 917 is formed with a larger outer diameter than the oil passage 211. When the contact portion 917 contacts the wall portion 682, the contact portion 917 is held in a state of being pressed against the outer peripheral edge surrounding the opening of the oil passage 211 by the urging force of the spring Sp.

[0147] In this state, the contact portion 917 contacts the wall portion 682 in a metallic contact state, thereby blocking the communication between the oil passage 211 and the first connection passage 901 on the hydraulic control circuit 95 side.

[0148] When the electric oil pump EOP is driven, the valve core 915 is pushed by the oil OL supplied from the oil path 211 and displaced in a direction away from the wall portion 682. As a result, the seal of the oil path 211 is released, and the oil OL supplied from the electric oil pump EOP side is supplied to the line pressure (main pressure) regulating valve 951 (see Figure 8 )side.

[0149] Here, the first connection passage 901 through which the oil OL from the electric oil pump EOP flows merges with the second connection passage 902 through which the oil OL from the mechanical oil pump MOP flows between the connection portion 911 and the line pressure regulating valve 951 .

[0150] 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 .

[0151] Here, when the electric oil pump EOP is not driven, since the valve element 915 seals the opening of the oil passage 211 , the inflow of the oil OL into the oil passage 211 on the electric oil pump EOP side is restricted.

[0152] like Figure 8 As shown, the second oil passage is composed of the oil passage 22 on the case 6 side (the wall portion 682 and the partition wall portion 62) and the second connecting passage 902 on the control valve CV side.

[0153] The oil passage 22 is an oil passage that connects a discharge port 140 of the mechanical oil pump MOP (second oil pump) and a connection port 98 to the control valve CV.

[0154] like Fig.11 As shown, the oil passage 22 is an oil passage extending linearly in 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 opened to the second chamber S2.

[0155] In the control valve CV, a connection portion 921 of the second connection passage 902 opens at a portion facing the connection port 98 of the oil passage 22 .

[0156] The connection portion 921 is a bottomed hole formed with its opening facing the wall portion 682. The connection portion 921 is formed with an inner diameter D921 larger than the inner diameter D221 of the oil passage 22.

[0157] The connecting portion 921 is provided with a valve element 925. The valve element 925 is composed of a cylindrical shaft portion 926 and a contact portion 927 provided at one end of the shaft portion 926.

[0158] 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 the axis X92 along the opening direction of the oil passage 22 .

[0159] A spring Sp is externally inserted into the support portion 922 and the shaft portion 926. The valve body 925 is urged toward the wall portion 682 by the urging force of the spring Sp.

[0160] The contact portion 927 is formed with a larger outer diameter than the oil passage 22. When the contact portion 927 contacts the wall portion 682, the contact portion 927 is held pressed against the outer peripheral edge surrounding the opening of the oil passage 22 by the urging force of the spring Sp.

[0161] In this state, the contact portion 927 contacts the wall portion 682 in a metallic contact state, thereby blocking the communication between the oil passage 22 and the second connection passage 902 on the hydraulic control circuit 95 side.

[0162] When the mechanical oil pump MOP is driven, the valve core 925 is pushed by the oil OL supplied from the oil passage 22 and displaced in a direction away from the wall portion 682. As a result, the seal of the oil passage 22 is released, and the oil OL supplied from the mechanical oil pump MOP side is supplied to the line pressure regulating valve 951 (see Figure 8 )side.

[0163] Here, the second connection passage 902 through which the oil OL from the mechanical oil pump MOP flows merges with the first connection passage 901 through which the oil OL from the electric oil pump EOP flows, between the connection portion 921 and the line pressure regulating valve 951 .

[0164] 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 .

[0165] Here, when the mechanical oil pump MOP is not driven, the valve element 925 seals the opening of the oil passage 22 , so that the inflow of the oil OL into the oil passage 22 on the electric oil pump EOP side is restricted.

[0166] Thus, in the control valve CV, the check valve 91 is provided at the connection portion of the first connection passage 901 with the oil passage 21 (oil passage 211 ). Furthermore, the check valve 92 is provided at the connection portion of the second connection passage 902 with the oil passage 22 .

[0167] The first connection passage 901 and the second connection passage 902 are oil passages provided in the control valve CV, and constitute a part of the hydraulic control circuit 95 in the control valve CV.

[0168] like Figure 8 As shown, the oil passage 904 before the confluence point P of the first connection passage 901 and the second connection passage 902 is connected to the line pressure regulating valve 951. In the oil passage 904, between the confluence point P and the line pressure regulating valve 951, an oil passage 905 connected to another pressure regulating valve is connected.

[0169] The hydraulic control circuit 95 in the control valve CV regulates the operating oil pressure of the power transmission mechanism (the forward / reverse switching mechanism 2 , the speed change mechanism 3 , etc.) according to the oil pressure generated by the oil pump OP.

[0170] The line pressure regulating valve 951 is the first pressure regulating valve to which the oil OL is supplied in the hydraulic control circuit 95. The line pressure regulating valve 951 adjusts the oil pressure (line pressure) supplied to other pressure regulating valves connected to the oil path 905 by adjusting the discharge amount of the oil OL in the line pressure regulating valve 951.

[0171] An oil passage 906 extending from the discharge port 96 of the oil OL is connected to the discharge 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.

[0172] The third connection passage 903 is connected to the oil passage 906 . Therefore, the 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 .

[0173] like Figure 8As shown, the third oil passage is composed of the oil passage 23 on the case 6 (wall portion 682, partition wall portion 62) side and the third connecting passage 903 on the control valve CV side.

[0174] The oil passage 23 is an oil passage that connects the suction port 72 of the electric oil pump EOP (first oil pump) and the filter 10 .

[0175] like Fig. 9 As shown, the oil passage 23 is composed of an oil passage 231 extending linearly in the partition wall portion 62 and an oil passage 232 extending linearly in the wall portion 682 .

[0176] 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 serves as a connection port 99 that opens to the second chamber S2.

[0177] The oil passage 232 is a blind hole formed in a direction along the rotation axis Xm of the mechanical oil pump MOP.

[0178] The opening on the base end 232 a side of the oil passage 232 is sealed by a plug PL. The front end 232 b of the oil passage 232 intersects with the oil passage 231 in the partition wall portion 62 .

[0179] In the oil passage 231 , a region where the oil passage 231 and the oil passage 232 intersect on the connection port 99 side becomes a branch passage 231 ′.

[0180] In the control valve CV, a connection portion 931 of the third connection passage 903 opens at a portion facing the connection port 99 (branch passage 231 ′) of the oil passage 231 .

[0181] In the region of the branch passage 231' in the oil passage 231, a relief valve 80 is inserted and arranged at the portion of the connection port 99. The relief valve 80 has a base 81 embedded in the connection port 99. The base 81 has a small diameter portion 811 and a large diameter portion 812. In the small diameter portion 811, a wall portion 82 is provided on the opposite side of the large diameter portion 812. The base 81 is formed in a bottomed cylindrical shape with the small diameter portion 811 side closed by the wall portion 82.

[0182] 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 in the base portion 81 to communicate with each other.

[0183] A support member 83 of the spring Sp is inserted into a region inside the large diameter portion 812 in the space S80.

[0184] 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 .

[0185] One end of the spring Sp contacts the surface of the small diameter portion 811 of the support member 83. The other end of the spring Sp contacts the ball B. The ball B is pressed against the wall 82 by the urging force of the spring Sp, and the through hole 82a provided in the wall 82 is sealed by the ball B.

[0186] A discharge port 83a is provided at the center of the support member 83. The discharge port 83a allows the space S80 in which the spherical body B is accommodated to communicate with the connection portion 931.

[0187] A seal ring S is fitted around the outer periphery of the large diameter portion 812 . The seal ring S seals a gap between the outer periphery of the large diameter portion 812 and the inner periphery of the connection port 99 .

[0188] In the relief valve 80, when the pressure in the oil passage 23 (oil passage 231) reaches or exceeds the reference pressure, the ball B compresses the spring Sp and moves in a direction away from the wall portion 82. As a result, the sealing of the through hole 82a by the ball B is released, 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.

[0189] As described above, the third connection passage 903 communicates with the oil passage 906 that connects the discharge port of the line pressure regulating valve 951 and the discharge port 96 of the oil OL (see Figure 8 ).

[0190] Therefore, the oil OL discharged from the relief valve 80 to the third connection passage 903 is finally discharged from the discharge port 96 of the control valve CV into the second chamber S2 (see Figure 7 ).

[0191] like Figure 7 As shown, in the housing 6 , the connection port 99 of the oil passage 23 , the connection port 97 of the oil passage 21 , and the connection port 98 of the oil passage 22 are arranged side by side in the vertical direction in a region of the wall portion 682 that overlaps with the partition wall portion 62 .

[0192] These connection ports 97 , 98 , 99 are provided in a positional relationship overlapping with the control valve CV.

[0193] Therefore, when the control valve CV is almost set to the second chamber S2, the connection ports 97, 98, 99 and the connection passages (901, 902, 903) on the control valve CV side are connected.

[0194] Next, the operation of the hydraulic circuit 20 will be described.

[0195] In the hydraulic circuit 20, when the electric oil pump EOP is not driven, the valve element 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.

[0196] In this state, when the mechanical oil pump MOP is driven, the valve element 925 (see Fig.11 ) is pushed by the oil OL supplied from the oil passage 22 and displaced in the direction away from the wall portion 682. As a result, the seal of the oil passage 22 is released, and the oil OL supplied from the mechanical oil pump MOP side is supplied to the line pressure regulating valve 951 (see Figure 8 )side.

[0197] As described above, the second connection passage 902 merges with the first connection passage 901 in the hydraulic control circuit 95. Therefore, when the mechanical oil pump MOP is driven, the oil OL also flows into the connection portion 911 (see Fig.10 )Inside.

[0198] Thus, the pressure in the connection portion 911 increases due to the inflowing oil. Here, the abutment portion 917 of the valve core 915 of the check valve 91 contacts the wall portion 682 in a metal contact state. Therefore, when the pressure in the connection portion 911 increases, the oil OL may flow into the oil path 21 through the contact interface between the abutment portion 917 and the wall portion 682. In this case, the pressure of the oil OL in the oil path 21 between the check valve 91 and the electric oil pump EOP increases.

[0199] Here, if the electric oil pump EOP connected to the oil passage 21 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 also increases.

[0200] The oil circuit 23 connects the electric oil pump EOP and the filter 10, and a check valve 18 is provided between the oil circuit 23 and the filter 10 (see Fig. 9 ).

[0201] Therefore, the pressure increase of the oil passage 21 due to the inflow of the oil OL from the control valve CV side causes the pressure increase of the oil OL in the oil passage 23 .

[0202] In the present embodiment, the oil passage 231 constituting the oil passage 23 has a connection port 99 opened to the surface on the second chamber S2 side of the wall portion 682. The relief valve 80 is provided in the connection port 99.

[0203] 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 exceeding the reference pressure.

[0204] Here, when the connection port 99 is closed with a plug without providing the relief valve 80 in the connection port 99 , the pressure in the oil passage 23 acts on the check valve 18 on the filter 10 side.

[0205] like Figure 3 As shown, the check valve 18 has the other end 180b of the cylindrical main body 180 embedded in the connecting portion 625 on the side of the partition wall 62. In addition, a seal ring S embedded in 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 connecting port 625a of the connecting portion 625.

[0206] When the pressure of the oil OL in the oil circuit 23 (oil circuit 231) becomes high, the pressure acts on the sealing ring S provided on the outer periphery of the other end 180b side of the main body 180. As a result, a force acts on the sealing ring S toward the one end 18a side (the right side in the figure) of the main body 180. As a result, the sealing ring S may fall off from the groove 181. When the sealing 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 connecting port 625a is released. In this state, if the electric oil pump EOP is driven, air may be sucked in from the released gap.

[0207] As described above, in the present embodiment, the relief valve 80 is provided in the oil passage 23 (oil passage 231), and 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. Therefore, the possibility that the excessive pressure affects the check valve 18 on the filter 10 side can be reduced. Thus, the possibility that the sealing performance of the check valve 18 on the filter 10 side is affected can be suppressed.

[0208] As described above, the hydraulic circuit 20 of the present embodiment has the following structure.

[0209] (1) The hydraulic circuit 20 has:

[0210] A first oil passage (the oil passage 21 , the first connecting passage 901 ) communicating with the discharge port 71 of the electric oil pump EOP (the first oil pump);

[0211] A second oil passage (the oil passage 22 , the second connecting passage 902 ) communicating with the discharge port 140 of the mechanical oil pump MOP (the second oil pump);

[0212] An oil pressure control circuit 95 having a line pressure regulating valve 951 (first pressure regulating valve) is arranged downstream of a confluence point P of the first oil passage (first connecting passage 901) and the second oil passage (second connecting passage 902);

[0213] An oil passage 23 (third oil passage) connecting the suction port 72 of the electric oil pump EOP and the filter 10;

[0214] A check valve 18 provided in the oil passage 23 and restricting the oil OL from moving toward the filter 10 side;

[0215] The relief valve 80 is provided in the oil passage 23 and discharges the oil OL in the oil passage 23 to the outside when the pressure in the oil passage 23 exceeds a reference pressure.

[0216] With this configuration, when the pressure in the oil passage 23 exceeds the reference pressure, the oil OL in the oil passage 23 is discharged to the outside from the relief valve 80 , thereby suppressing a pressure increase in the oil passage (the oil passage 23 , the oil passage 21 ) on the electric oil pump EOP side.

[0217] (2) The hydraulic circuit 20 includes the partition wall portion 62 (support wall) that supports the filter 10 .

[0218] The partition wall portion 62 is provided with an oil passage 23 (third oil passage) and a connection port 625 a communicating with the oil passage 23 .

[0219] The check valve 18 has a main body portion 180 that is fitted into the connection port 625 a and functions as a connection member that allows the filter 10 and the oil passage 23 to communicate with each other.

[0220] A seal ring S is fitted on the outer periphery of the main body 180 to seal a gap between the inner periphery of the connection port 625 a and the outer periphery of the main body 180 .

[0221] In the case where the relief valve 80 is not provided, when the pressure in the oil passage 23 increases, the seal ring S rolls up under the pressure, and a gap may be generated 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 is sucked from the generated gap, and the discharge pressure of the electric oil pump EOP may be unstable.

[0222] 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 before the pressure reaches a level at which the seal ring S turns over and a gap is generated, thereby reducing the pressure in the oil passage 23 .

[0223] This can reduce the possibility that a gap is generated between the outer periphery of the main body 180 and the inner periphery of the connection port 625 a and the discharge pressure of the electric oil pump EOP becomes unstable.

[0224] (3) The hydraulic circuit 20 includes the control valve CV having the hydraulic control circuit 95 therein.

[0225] The first oil passage is composed of the oil passage 21 on the partition wall portion 62 side (the oil passage on the support wall side) and the first connecting passage 901 on the control valve CV side (the oil passage on the control valve side).

[0226] A check valve 91 (first check valve) that restricts the oil OL from moving toward the electric oil pump EOP is provided at a connection portion between the oil passage 21 and the first connection passage 901 .

[0227] Since the first oil passage (first connecting passage 901 ) and the second oil passage (second connecting passage 902 ) merge in 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 .

[0228] Therefore, although the check valve 91 is provided to restrict the movement of the oil OL toward the electric oil pump EOP, if the pressure of the oil OL toward the electric oil pump EOP increases, the oil OL may enter the oil passage 21. In this case, the pressure on the electric oil pump EOP side is higher than the check valve 91.

[0229] As described above, since the relief valve 80 is provided in the oil passage 23 connected to the suction port 72 of the electric oil pump EOP, it is possible to prevent the pressure on the oil passage 23 side from increasing to a reference pressure or more.

[0230] (4) The partition wall portion 62 (support wall) includes the wall portion 682 (partition wall) that partitions the first chamber S1 in which the filter 10 is arranged and the second chamber S2 in which the control valve CV is arranged.

[0231] The control valve CV is mounted on the wall portion 682 .

[0232] The oil passage 21 on the partition wall portion 62 (support wall portion) side opens at a portion of the wall portion 682 that faces the control valve CV.

[0233] 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 at the shortest distance. In addition, by opening the oil passage 21 on the joint surface of the control valve CV of the wall portion 682, leakage of oil OL from the connection portion between the oil passage 21 and the first connection passage 901 can be suppressed.

[0234] (5) The check valve 91 includes the valve element 915 having the contact portion 917 having a diameter larger than the opening diameter (inner diameter D211 ) of the oil passage 211 on the partition wall portion 62 side.

[0235] The valve element 915 is displaceable in the direction of the axis X91 along the opening direction of the oil passage 21 (oil passage 211 ).

[0236] The abutment portion 917 of the valve element 915 contacts the peripheral edge of the wall portion 682 surrounding the opening of the oil passage 211 in a metallic contact state, thereby blocking the communication between the oil passage 21 (oil passage 211 ) and the first connection passage 901 .

[0237] Therefore, when the pressure on the first connection passage 901 side becomes high, the oil OL may flow into the oil passage 21 (oil passage 211 ) through the contact interface between the abutment portion 917 and the wall portion 682 .

[0238] In this case, the pressure in not only the oil passage 21 between the check valve 91 and the electric oil pump EOP but also the oil passage 23 connecting the electric oil pump EOP and the filter 10 increases.

[0239] 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 and 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 a gap is generated, the possibility of the pressure in the oil passages 21 and 23 becoming too high and generating 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 can be reduced.

[0240] (6) In the oil passage 23 (third oil passage), a region of the oil passage 231 closer to the wall portion 682 than the intersection with the oil passage 232 forms a branch passage 231 ′ that opens to the surface of the wall portion 682 (partitioning wall) on the second chamber S2 side.

[0241] The relief valve 80 is provided in a region of the branch passage 231 ′ of the oil passage 231 .

[0242] According to this structure, by inserting the relief valve 80 into the branch passage 231 ′ opened to the second chamber S2 , the relief valve 80 can be arranged without hindering the movement of the oil OL between the filter 10 and the electric oil pump EOP.

[0243] (7) The discharge port 83a of the relief valve 80 is connected to the oil passage 906 constituting the drain circuit via the third connection passage 903 in the control valve CV.

[0244] The oil OL discharged from the discharge port 83 a is used to take in the oil OL from the filter 10 .

[0245] Therefore, the discharge port 96 of the oil OL of the discharge circuit opens at a position suitable for returning the oil OL to the filter 10. Therefore, by connecting the discharge port 83a of the relief valve 80 to the discharge circuit, the oil OL discharged from the relief valve 80 can be discharged to a position suitable for returning the oil OL to the filter 10. Therefore, when the hydraulic circuit 20 is applied to the power transmission device 1 for a vehicle, the amount of the oil OL stored in the housing HS of the power transmission device 1 can be suppressed. Therefore, it can be expected that the fuel consumption rate and the power consumption rate of the vehicle equipped with the power transmission device 1 will be improved.

[0246] (I) The second oil passage is composed of the oil passage 22 on the partition wall portion 62 (support wall) side and the second connecting passage 902 on the control valve CV side.

[0247] A check valve 92 (second check valve) that restricts the oil OL from moving toward the mechanical oil pump MOP is provided at a connection portion between the oil passage 22 and the second connection passage 902 .

[0248] The check valve 92 includes a valve element 925 having an abutment portion 927 having a larger diameter than the opening of the oil passage 22 opened to the wall portion 682 .

[0249] The valve core 925 is displaceable in the direction of the axis X92 along the opening direction of the oil passage 22 .

[0250] The abutment portion 927 of the valve element 925 contacts the peripheral edge of the wall portion 682 surrounding the opening of the oil passage 22 in a metallic contact state, thereby blocking the communication between the oil passage 22 and the second connection passage 902 .

[0251] Therefore, when the mechanical oil pump MOP is not driven, even if the electric oil pump EOP is driven, the oil OL flowing into the second connecting passage 902 from the first connecting passage 901 side can be prevented from flowing into the oil passage 22 .

[0252] (II) 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 region of the wall portion 682 that overlaps with the partition wall portion 62 (see Figure 7 ).

[0253] In the wall portion 682 , the connection ports 97 , 98 , 99 are arranged in a positional relationship overlapping with the control valve CV.

[0254] The area of ​​the wall portion 682 that overlaps the partition portion 62 is a relatively rigid area of ​​the housing 6. When the connection ports 97 and 98 are opened in this area, stability can be ensured when the valve cores 915 and 925 are brought into contact with the peripheral edges of the openings of the connection ports 97 and 98. Thus, the connection ports 97 and 98 openings can be reliably closed by the valve cores 915 and 925.

[0255] Furthermore, the installation of the control valve CV in the second chamber S2 and the connection of the connection passages (the first connection passage 901 , the second connection passage 902 , and the third connection passage 903 ) on the control valve CV side with the connection ports 97 , 98 , and 99 can be completed simultaneously.

[0256] In the above embodiment, the connection port 99 on the base end side of the oil passage 231 is opened at a position opposite to the control valve CV, and the oil OL discharged from the relief valve 80 provided at the connection port 99 is discharged to the third connection passage 903 on the control valve CV side.

[0257] The oil OL discharged from the relief valve 80 may be directly discharged into the second chamber S2 or the first chamber S1 that accommodates the control valve CV.

[0258] In the above embodiment, if Figure 7, the example shows a case where 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 region of the wall portion 682 overlapping the partition wall portion 62 , as viewed from the vehicle front side of the power transmission device 1 .

[0259] 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 changed as appropriate depending on the arrangement of the connection path on the control valve CV side.

[0260] In the above embodiment, the case where the power transmission device 1 transmits the rotation of the engine ENG to the drive wheels WH, WH is exemplified, but the power transmission device 1 may also transmit the rotation of at least one of the engine ENG and the electric motor (rotating electric machine) to the drive wheels WH, WH. For example, the power transmission device may be a single-motor, dual-clutch type (a method in which an electric motor is arranged between the engine ENG and the power transmission device, a first clutch is arranged between the engine ENG and the electric motor, and a second clutch is arranged in the power transmission device 1).

[0261] In addition, in the above-mentioned embodiment, the case where the power transmission device 1 has a speed change function is illustrated, but the power transmission mechanism may not have a speed change function, but simply decelerates (or speeds up). In the case where the power transmission device does not have a speed change function, and the power transmission device is a structure that decelerates the rotation of the motor and transmits it to the drive wheels WH, WH, the oil pressure control circuit for supplying the oil OL for cooling the motor and the oil OL for lubricating the speed reduction mechanism is arranged in the storage chamber S3 together with the electric oil pump EOP. In addition, in the above-mentioned embodiment, the case where the control unit of the power transmission device 1 has a control valve CV is illustrated, but the power transmission device 1 may also be a control unit having an inverter or the like that drives and controls the motor when the driving source is not the engine ENG but the motor (rotating electric machine).

[0262] Furthermore, the present invention can also be applied to objects other than vehicles.

[0263] The embodiment of the present invention has been described above, but the above embodiment is only an application example of the present invention and does not mean that the technical scope of the present invention is limited to the specific structure of the above embodiment. It can be appropriately changed within the scope of the technical idea of ​​the invention.

[0264] Explanation of symbols

[0265] 6: Shell

[0266] 10: Filter

[0267] 18: Check valve

[0268] 20: Hydraulic circuit

[0269] 21: Oil passage (first oil passage: oil passage on the supporting wall side)

[0270] 22: Oil circuit (second oil circuit)

[0271] 23: Oil circuit (the third oil circuit)

[0272] 62: Partition wall (support wall)

[0273] 71: Exhaust port

[0274] 72: Suction port

[0275] 80: Relief valve

[0276] 91: Check valve (first check valve)

[0277] 95: Hydraulic control circuit

[0278] 99: Connection port (discharge port of the relief valve)

[0279] 140: Exhaust port

[0280] 180: Main body (connecting part)

[0281] 211: Oil passage (second oil passage: oil passage on the supporting wall side)

[0282] 212: Oil circuit (first oil circuit)

[0283] 231: Oil circuit (the third oil circuit)

[0284] 231: Branch road (third oil road)

[0285] 232: Oil circuit (the third oil circuit)

[0286] 625a: Connector

[0287] 682: Wall (dividing wall)

[0288] 901: First connecting path (first oil path: oil path on the control valve side)

[0289] 902: Second connecting passage (second oil passage)

[0290] 906: Oil circuit (discharge circuit)

[0291] 917: Contact Department

[0292] 951: Line pressure regulating valve (first pressure regulating valve)

[0293] CV: Control Valve

[0294] EOP: Electric oil pump (first oil pump)

[0295] MOP: Mechanical oil pump (second oil pump)

[0296] OL: Oil

[0297] P: Confluence point

[0298] S: Sealing ring

[0299] S1: First Room

[0300] S2: Second Chamber

Claims

1. A hydraulic circuit having: a first oil passage, which is in communication with a discharge port of the first oil pump; a second oil passage, which is in communication with a discharge port of a second oil pump; an oil pressure control circuit, wherein a first pressure regulating valve is arranged downstream of a confluence point of the first oil circuit and the second oil circuit; a third oil circuit, connecting the suction port of the first oil pump and a filter; A check valve is provided in the third oil passage and restricts the movement of oil to the filter side, wherein: The oil pressure circuit also has: The relief valve is provided in the third oil passage and discharges the oil in the third oil passage to the outside when the pressure in the third oil passage exceeds a reference pressure.

2. The hydraulic circuit according to claim 1, wherein: having a supporting wall for supporting the filter, The supporting wall is provided with the third oil passage and a connection port communicating with the third oil passage. The check valve has a connecting component embedded in the connecting port and connecting the filter and the third oil passage. A seal ring is fitted on the outer periphery of the connecting member to seal a gap between the connecting member and the inner periphery of the connecting port.

3. The hydraulic circuit according to claim 2, wherein: A control valve having the oil pressure control circuit inside. The first oil passage is composed of the oil passage on the support wall side and the oil passage on the control valve side. A first check valve is provided at a connection portion between the oil passage on the support wall side and the oil passage on the control valve side.

4. The hydraulic circuit according to claim 3, wherein: The support wall has a partition wall that partitions a first chamber and a second chamber, the filter is disposed in the first chamber, and the control valve is disposed in the second chamber. The control valve is installed on the partition wall. The oil passage on the support wall side opens at a portion of the partition wall facing the control valve.

5. The hydraulic circuit according to claim 4, wherein: The first check valve includes a valve element having a diameter larger than an opening diameter of the oil passage on the support wall side, and the valve element is displaceable in an opening direction of the oil passage on the support wall side.

6. The hydraulic circuit according to claim 4, wherein: The third oil passage has a branch passage opening toward the partition wall. The overflow valve is arranged on the branch path.

7. The hydraulic circuit according to any one of claims 1 to 6, wherein: The discharge port of the relief valve is communicated with the discharge circuit.

Images