unit

Abstract

Operate the oil pump efficiently. [Solution] The unit includes an oil pump, a differential gear having a differential case having a nozzle connected downstream of the oil pump, a window portion through which oil is supplied from the nozzle, and a wall portion adjacent to the window portion, and a valve that stops the supply of oil from the nozzle when the nozzle and the wall portion face each other during rotation of the differential case.

Description

Technical Field

[0001] The present invention relates to a unit.

Background Art

[0002] Patent Document 1 discloses a configuration in which oil is supplied from a nozzle to a window provided in a differential case.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The oil supply from the nozzle is performed using an oil pump. Therefore, it is required to efficiently operate the oil pump.

Means for Solving the Problems

[0005] The unit according to an aspect of the present invention includes an oil pump, a nozzle connected downstream of the oil pump, a differential gear having a differential case having a window portion to which oil is supplied from the nozzle, and a wall portion adjacent to the window portion, and a valve that stops the supply of oil from the nozzle when the nozzle and the wall portion face each other during rotation of the differential case.

Effects of the Invention

[0006] According to an aspect of the present invention, the oil pump can be efficiently operated.

Brief Description of the Drawings

[0007] [Figure 1] Figure 1 is a schematic diagram showing the general configuration of the unit. [Figure 2] Figure 2 is a diagram illustrating the differential gear. [Figure 3] Figure 3 is a diagram illustrating the differential gear. [Figure 4] Figure 4 is a diagram illustrating a valve. [Figure 5] Figure 5 is a diagram illustrating a valve. [Figure 6] Figure 6 is a diagram illustrating a valve. [Figure 7] Figure 7 is a diagram illustrating a valve. [Figure 8] Figure 8 is a diagram illustrating the operation of the valve. [Figure 9] Figure 9 is a diagram illustrating the unit related to Modification Example 1. [Figure 10] Figure 10 is a diagram illustrating the unit related to Modification Example 1. [Figure 11] Figure 11 is a diagram illustrating the unit related to Modification Example 2.

[0008] First, the definitions of terms used in this specification will be explained. A "unit" is also called a "motor unit," "power transmission device," etc. A motor unit is a unit that has at least a motor. A power transmission device is a device that has at least a power transmission mechanism, and the power transmission mechanism is, for example, a gear mechanism and / or a differential gear mechanism. A unit that has a motor and a power transmission mechanism belongs to both the concepts of a motor unit and a power transmission device.

[0009] A "housing" is a component that houses the motor, gears, and inverter. A housing consists of one or more cases.

[0010] A "motor" is a rotating electric machine that has both electric motor and / or generator functions.

[0011] When it is stated that element B (such as a component or a part) is connected to element A (such as a component or a part), element B (such as a component or a part) is connected downstream of element A, or element B (such as a component or a part) is connected upstream of element A, it means that element A and element B are connected in a power-transmittable manner. The power input side is upstream and the power output side is downstream. Also, element A and element B may be connected via other elements (such as a clutch or other gear mechanisms).

[0012] "Overlap in a predetermined direction view" means that a plurality of elements are arranged in a predetermined direction, and is synonymous with the case of being described as "overlap in a predetermined direction". The "predetermined direction" is, for example, the axial direction, the radial direction, the gravitational direction, the vehicle traveling direction (the vehicle forward direction, the vehicle backward direction), etc. When it is illustrated on the drawing that a plurality of elements (such as components or parts) are arranged in a predetermined direction, in the description of the specification, it may be regarded that there is a sentence explaining that they overlap in the predetermined direction view.

[0013] "Not overlapping in a predetermined direction view" and "offset in a predetermined direction view" mean that a plurality of elements are not arranged in a predetermined direction, and are synonymous with the case of being described as "not overlapping in a predetermined direction" and "offset in a predetermined direction". The "predetermined direction" is, for example, the axial direction, the radial direction, the gravitational direction, the vehicle traveling direction (the vehicle forward direction, the vehicle backward direction), etc. When it is illustrated on the drawing that a plurality of elements (such as components or parts) are not arranged in a predetermined direction, in the description of the specification, it may be regarded that there is a sentence explaining that they do not overlap in the predetermined direction view.

[0014] "In the specified direction view, element A (component, part, etc.) is located between element B (component, part, etc.) and element C (component, part, etc.)" means that when observed from the specified direction, it can be observed that element A is between element B and element C. The "specified direction" is, for example, the axial direction, the radial direction, the gravitational direction, the vehicle traveling direction (vehicle forward direction, vehicle reverse direction), etc. For example, when element B, element A, and element C are arranged in this order along the axial direction, it can be said that in the radial direction view, element A is located between element B and element C. On the drawing, when it is illustrated that element A is between element B and element C in the specified direction view, it may be regarded that there is a sentence in the description of the specification explaining that element A is between element B and element C in the specified direction view.

[0015] In the axial direction view, when two elements (components, parts, etc.) overlap, the two elements are coaxial.

[0016] The "axial direction" means the axial direction of the rotation axis of the components constituting the unit. The "radial direction" means the direction perpendicular to the rotation axis of the components constituting the unit. The components are, for example, a motor, a gear mechanism, a differential gear mechanism, etc.

[0017] Hereinafter, this embodiment will be described. In this embodiment, the unit 1 mounted on the vehicle will be described as an example. FIG. 1 is a schematic diagram showing a schematic configuration of the unit 1. FIG. 2 is a diagram for explaining the differential gear 6. FIG. 2 is a perspective view of the differential gear 6 as viewed from the rear side of the vehicle. FIG. 3 is a diagram for explaining the differential gear 6. FIG. 3 is an enlarged view around the differential gear 6 in FIG. 1.

[0018] Here, "vertical direction" in the drawings refers to the direction of the vertical line VL, relative to the state in which Unit 1 is mounted on the vehicle. Therefore, when it is written as "upper side," it means the "upper side" in the direction of the vertical line VL, and when it is written as "lower side," it means the "lower side" in the direction of the vertical line VL. Also, "front-rear direction" refers to the front-rear direction of the vehicle, relative to the state in which Unit 1 is mounted on the vehicle. Therefore, when it is written as "front side," it means the "front side" in the front-rear direction, and when it is written as "rear side," it means the "rear side" in the front-rear direction.

[0019] As shown in Figure 1, unit 1 has a housing HS that houses the motor 2 and the power transmission mechanism 3. The housing HS consists of a motor case 11 that houses the motor 2 and a gear case 12 that houses the power transmission mechanism 3.

[0020] In unit 1, the rotational driving force of motor 2 is transmitted to power transmission mechanism 3. Power transmission mechanism 3 includes an input shaft 4 that rotates integrally with motor 2, an intermediate shaft 5 that transmits the rotation of input shaft 4 to differential gear 6, and drive shafts 7 (7A, 7B) that output the rotation of differential gear 6 to the left and right drive wheels WH, WH.

[0021] The input shaft 4 has a shaft 40 that is mounted coaxially with the motor shaft 20 of the motor 2, and an input gear 41 formed on the outer circumference of the shaft 40. The shaft 40 is spline-fitted with the motor shaft 20 and rotates together with the motor shaft 20 around the rotation axis X1.

[0022] The intermediate shaft 5 consists of a shaft 50 that runs along a rotation axis X2 parallel to the rotation axis X1, and two gears with different outer diameters (a large-diameter gear 51 and a small-diameter gear 52). The large-diameter gear 51 and the small-diameter gear 52 are located on the outer circumference of the shaft 50 and rotate together with the shaft 50 around the rotation axis X2.

[0023] In the direction of the rotation axis X2, the large-diameter gear 51 is located closer to the motor 2 than the small-diameter gear 52. The large-diameter gear 51 of the intermediate shaft 5 meshes with the input gear 41 of the input shaft 4. The small-diameter gear 52 of the intermediate shaft 5 meshes with the final gear 61 of the differential gear 6.

[0024] The final gear 61 is fixed to the outer circumference of the differential case 60 and rotates integrally with the differential case 60 around the rotation axis X3. The rotation axis X3 is parallel to the rotation axes X1 and X2. The differential case 60 is connected to the drive shafts 7 (7A, 7B) via a pair of bevel gears 62, 62 and a pair of side gears 63, 63. A pinion mate shaft 64, supported by the differential case 60, is inserted through the pair of bevel gears 62, 62. Therefore, the drive shafts 7 (7A, 7B) rotate together with the final gear 61 around the rotation axis X3.

[0025] In unit 1, the motor shaft 20 and the rotation axis X1 of the input shaft 4, the rotation axis X2 of the intermediate shaft 5, and the rotation axis X3 of the differential gear 6 are arranged in this order from the front to the rear of the vehicle.

[0026] These rotating shafts X1 to X3 are oriented along the width of the vehicle. In the following, these rotating shafts X1 to X3 will be collectively referred to as rotating shaft X, as needed.

[0027] The motor case 11 has a support wall portion 111 surrounding the rotating shaft X1. The support wall portion 111 is oriented along the rotating shaft X1. The motor 2 is housed inside the support wall portion 111. The gear case 12 is joined to the front surface 111a of the support wall portion 111 with bolts (not shown).

[0028] The support wall 111 is provided with a wall portion 112 that extends inward between the motor 2 and the power transmission mechanism 3. The wall portion 112 is oriented perpendicular to the rotation axis X1. The space formed inside the motor case 11 and the gear case 12 is divided into two by a wall 112. The space on the motor 2 side from the wall 112 (upper side in the figure) is the motor chamber Sa that houses the motor 2. The space on the power transmission mechanism 3 side from the wall 112 (lower side in the figure) is the gear chamber Sb that houses the power transmission mechanism 3.

[0029] In the wall portion 112, a cylindrical wall portion 113 is provided in the region where the rotation axis X1 intersects, surrounding the rotation axis X1. A bearing Bm is provided on the inner circumference of the cylindrical wall portion 113 on the motor chamber Sa side. The motor shaft 20 is supported by the cylindrical wall portion 113 via the bearing Bm. A bearing B4 is provided on the inner circumference of the cylindrical wall portion 113 on the gear chamber Sb side. The shaft 40 of the input shaft 4 is supported by the cylindrical wall portion 113 via the bearing B4.

[0030] On the side of the wall portion 112 facing the power transmission mechanism 3 (lower side in the figure), a cylindrical wall portion 114 is provided behind the rotating shaft X1. The cylindrical wall portion 114 is cylindrical in shape and surrounds the rotating shaft X2. A bearing B5 is provided on the inner circumference of the cylindrical wall portion 114. The bearing B5 supports the shaft 50 of the intermediate shaft 5.

[0031] The motor case 11 has a wall portion 15 that protrudes rearward from the support wall portion 111 on the rear side (left side in the figure) of the vehicle. The wall portion 15 has a side wall 151 that protrudes from the outer circumference of the support wall portion 111 toward the rear side of the vehicle, and a peripheral wall 152 that surrounds the rear end of the side wall 151. The side wall 151 is provided in a direction perpendicular to the rotation axis X3. The peripheral wall 152 is provided in a direction along the rotation axis X3.

[0032] In the side wall 151, a cylindrical differential case support portion 153 is provided in the region where the rotation axis X3 intersects. The support cylinder 601 of the differential case 60 penetrates the differential case support portion 153 in the direction of the rotation axis X3.

[0033] A bearing B6 is supported on the inner circumference of the differential case support portion 153. The support cylinder 601 of the differential case 60 is supported by the differential case support portion 153 via the bearing B6.

[0034] The tip surface 152a of the peripheral wall 152 is flush with the tip surface 111a of the support wall portion 111. The gear case 12 is joined to the tip surface 152a of the peripheral wall 152 by bolts (not shown).

[0035] The gear case 12 has a bottom wall portion 120 provided in a direction perpendicular to the rotation axes X1 to X3, and a peripheral wall portion 121 that surrounds the outer edge of the bottom wall portion 120 over its entire circumference. The bottom wall portion 120 is provided with a bulging wall portion 16 that bulges away from the motor case 11 in the region where the rotating shaft X3 intersects. The bulging wall portion 16 is formed by enlarging a portion of the gear case 12 in order to accommodate the differential case 60 of the differential gear 6.

[0036] The front end surface 121a of the peripheral wall portion 121 is joined to the front end surface 111a of the support wall portion 111 in the front region in the vehicle's longitudinal direction (the region on the right in Figure 1), and to the rear region (the region on the left in Figure 1) is joined to the front end surface 152a of the peripheral wall 152 of the wall portion 15.

[0037] In the bottom wall portion 120, a bearing B4 is provided in the region where the rotating shafts X1 intersect. The bearing B4 supports the shaft 40 of the input shaft 4. As a result, the input shaft 4 is supported at both ends in the direction of the rotation axis X1 by the motor case 11 and the gear case 12, and is provided to be rotatable around the rotation axis X1.

[0038] In the bottom wall portion 120, a bearing B5 is provided in the region where the rotating shafts X2 intersect. The bearing B5 supports the shaft 50 of the intermediate shaft 5. As a result, the intermediate shaft 5 is supported at both ends in the direction of the rotation axis X2 by the motor case 11 side and the gear case 12 side, and is provided to be rotatable around the rotation axis X2.

[0039] The bulging wall portion 16 accommodates the area in the differential case 60 to which the drive shaft 7B is connected. The bulging wall portion 16 is connected to the bottom wall portion 120 and includes a cylindrical wall portion 161 surrounding the differential case 60, a cylindrical differential case support portion 163 surrounding the support cylinder 602 of the differential case 60, and a connecting wall portion 162 connecting the cylindrical wall portion 161 and the differential case support portion 163.

[0040] The connecting wall portion 162 has a tapered shape that decreases in diameter from the cylindrical wall portion 161 toward the differential case support portion 163. A bearing B6 is supported on the inner circumference of the differential case support portion 163. The support cylinder 602 of the differential case 60 is supported by the differential case support portion 163 via the bearing B6. As a result, the differential case 60 is supported at both ends in the direction of the rotation axis X3 by the motor case 11 side and the gear case 12 side, and is provided to be rotatable around the rotation axis X3.

[0041] Drive shafts 7A and 7B are inserted through the inner circumferences of the support cylinders 601 and 602 of the differential case 60. The rotation of the differential case 60 is transmitted to the drive shafts 7A and 7B via the bevel gear 62 and the side gear 63. Therefore, in conjunction with the rotation of the differential case 60, the drive shafts 7A and 7B also rotate around the rotation axis X3.

[0042] Motor 2 includes a motor shaft 20, a cylindrical rotor 21 fitted onto the motor shaft 20, and a stator 22 that surrounds the outer circumference of the rotor 21 at intervals. The stator 22 is inserted into the inner circumference of the support wall 111.

[0043] Bearing Bm is externally fitted to the motor shaft 20. Although not shown in the diagram, bearing Bm is provided at both ends of the motor shaft 20 in the direction of the rotation axis X1. The motor shaft 20 is rotatably supported by the motor case 11 via bearing Bm.

[0044] When power is supplied to the stator 22 of motor 2, a magnetic field is generated around the stator 22. This causes the rotor 21 and motor shaft 20 to rotate around the rotation axis X1, driving motor 2. The rotation of the motor shaft 20 is transmitted in the order of the input shaft 4, intermediate shaft 5, and differential gear 6 of the power transmission mechanism 3, and is finally output from the drive shafts 7A and 7B.

[0045] As shown in Figure 2, the differential case 60 has a window portion 65 that connects the inside and outside of the differential case 60, and a wall portion 66 that connects the support cylinder 602 and the final gear 61. The window portion 65 and the wall portion 66 are arranged alternately at approximately 90° intervals in the circumferential direction around the rotation axis X3.

[0046] As shown in Figure 3, when viewed from the radial direction of the rotation axis X3, a portion of the bevel gear 62, side gear 63, and pinion mate shaft 64 of the differential gear 6 is exposed through the window 65 of the differential case 60.

[0047] As shown in Figure 1, Unit 1 includes an electric oil pump EOP (oil pump) and a strainer ST. The oil OL in the housing HS is drawn in and pressurized by the electric oil pump EOP. At this time, the oil OL in the housing HS is filtered by the strainer ST.

[0048] The oil OL, pressurized by the electric oil pump EOP, is supplied to each part of unit 1. For example, a portion of the oil OL pressurized by the electric oil pump EOP is supplied to the motor 2 through an oil passage (not shown) to cool the stator 22. Another portion of the oil OL is supplied to each bearing Bm, B4-B6 through an oil passage (not shown) to lubricate them. A portion of the oil OL is also supplied to the differential gear 6 through an oil passage 165 (described later) to lubricate the bevel gear 62, side gear 63, and pinion mate shaft 64.

[0049] Increasing the number of oil supply points will increase the required oil supply volume, which will result in higher power consumption for the electric oil pump (EOP).

[0050] Here, oil OL is discharged to the differential gear 6 from the outer diameter side of the differential case 60. During rotation of the differential case 60, there are times when the oil OL discharged from the outer diameter side passes through the window portion 65 and reaches the inside of the differential case 60 (see Figure 4), and times when it is blocked by the wall portion 66 and does not reach the inside of the differential case 60 (see Figure 5).

[0051] Consequently, of the oil OL supplied from the electric oil pump EOP to the differential gear 6, the portion that is shielded by the wall 66 is wasted and does not contribute to the lubrication of the bevel gear 62, side gear 63, and pinion mate shaft 64. In other words, the power consumption of the electric oil pump EOP is wasted because it is driven to supply this wasted oil OL.

[0052] Therefore, in order to reduce the power consumption of the electric oil pump EOP, the unit 1 according to this embodiment has a valve 8 that controls the timing of the oil OL discharged toward the differential gear 6.

[0053] Figure 4 is a diagram illustrating valve 8. Figure 4 is a schematic diagram of cross-section AA in Figure 3. Figure 5 is a diagram illustrating valve 8. Figure 5 shows the differential gear 6 shown in Figure 4 rotated 90° around the rotation axis X3. Figure 6 is a diagram illustrating valve 8. Figure 6 is an enlarged view of area B in Figure 3. Figure 7 is a diagram illustrating valve 8. Figure 7 is a schematic diagram of cross-section AA in Figure 6.

[0054] As shown in Figure 4, the cylindrical wall portion 161 of the bulging wall portion 16 surrounds the differential case 60 around its entire circumference. An oil passage 165 is formed between the inner circumferential surface 161a and the outer circumferential surface 161b of the cylindrical wall portion 161. The oil passage 165 is provided to cross the front side of the differential case 60 in the vertical direction.

[0055] An intake hole 166 is connected to the lower end of the oil passage 165. The intake hole 166 is oriented along the vertical direction. The intake hole 166 opens into the outer circumferential surface 161b of the cylindrical wall portion 161. The intake hole 166 is connected to the electric oil pump EOP via piping Ha.

[0056] A discharge hole 167 (nozzle) is connected to the upper end of the oil passage 165. The discharge hole 167 is connected downstream of the electric oil pump EOP. The discharge hole 167 is located in the region where the vertical line VL passing through the rotation axis X3 intersects. The discharge hole 167 opens into the inner circumferential surface 161a of the cylindrical wall portion 161.

[0057] The oil OL, pressurized by the electric oil pump EOP, is delivered through piping Ha from the intake hole 166 to the oil passage 165. The oil OL in the oil passage 165 flows from the lower end to the upper end of the oil passage 165, and is then discharged from the discharge hole 167 toward the differential case 60.

[0058] A valve 8 is provided between the lower and upper ends of the oil passage 165. The flow of oil OL in the oil passage 165 is switched between permitted and restricted by the valve 8. The valve 8 includes a valve body 82 positioned to cross the oil passage 165, a spring 83 that provides a biasing force to the valve body 82, and a case portion 80 that houses the valve body 82 and the spring 83.

[0059] The case portion 80 is a part of the cylindrical wall portion 161 that has been thickened. The case portion 80 protrudes from the outer circumferential surface 161b of the cylindrical wall portion 161 along the direction of the diameter line Lr passing through the rotation axis X3. The diameter line Lr is perpendicular to the vertical line VL.

[0060] The case portion 80 is provided with a housing hole 85 for housing the valve body 82 and the spring 83. The housing hole 85 is oriented along the diameter line Lr. The housing hole 85 connects the front surface 80a of the case portion 80 to the oil passage 165.

[0061] As shown in Figure 6, the housing hole 85 has a hole diameter D2 that is larger than the hole diameter D1 of the oil passage 165 (D2 > D1). As shown in Figure 7, the housing hole 85 has a first region 851 that penetrates the case portion 80 and a second region 852 that connects the first region 851 with the oil passage 165.

[0062] The second region 852 is formed in a hemispherical shape that crosses the oil passage 165 in the direction of the diameter line Lr and is recessed away from the first region 851. The radius of curvature of the second region 852 is approximately consistent with the radius of curvature of the head 820 of the valve body 82, which will be described later.

[0063] A lid portion 81 is joined to the front surface 80a of the case portion 80. The lid portion 81 is fixed to the case portion 80 by bolts (not shown). As a result, the housing hole 85 is closed by the lid portion 81.

[0064] As shown in Figure 7, within the housing hole 85, the valve body 82 and the spring 83 are arranged along the diameter line Lr. In the direction of the diameter line Lr, the spring 83 is positioned between the valve body 82 and the cover portion 81. In this state, the spring 83 applies a biasing force to the valve body 82 in a direction away from the cover portion 81. As shown in Figure 4, the circumferential angular range from the valve body 82 to the discharge hole 167, viewed from the rotation axis X3, is 90°.

[0065] As shown in Figure 6, the valve body 82 has a spherical head 820 and a rod-shaped driven link 821 integrally formed with the head 820. The head 820 has a diameter that substantially matches the hole diameter D2 of the housing hole 85. Therefore, the head 820 also has a larger diameter than the hole diameter D1 of the oil passage 165.

[0066] As shown in Figure 7, the driven link 821 is positioned along the diameter line Lr. The driven link 821 is located on the opposite side of the spring 83 when viewed from the head 820. As shown in Figure 6, the width W of the driven link 821 in the direction of the rotation axis X3 is smaller than the bore diameter D1 of the oil passage 165 (W <D1)。

[0067] As shown in Figure 7, the cylindrical wall portion 161 is provided with a communication hole 169 that connects the inner circumferential surface 161a with the second region 852 of the housing hole 85. The communication hole 169 is provided in the region of the cylindrical wall portion 161 that intersects with the diameter line Lr. The valve body 82 has its head 820 housed in the housing hole 85, with the driven link 821 passing through the communication hole 169. The tip of the driven link 821 protrudes into the gear chamber Sb.

[0068] A guide roller 823 is provided at the tip of the driven link 821. The guide roller 823 is supported by the driven link 821 so as to be rotatable around a rotation axis Xa parallel to the rotation axis X3. The guide roller 823 can be, for example, a known cam follower.

[0069] In valve 8, the valve body 82, spring 83, and cover portion 81 are arranged in this order from the inner diameter side to the outer diameter side in the direction of the diameter line Lr. In valve body 82, the guide roller 823, driven link 821, and head portion 820 are arranged in this order from the inner diameter side to the outer diameter side in the direction of the diameter line Lr.

[0070] When an external force (see rightward arrow in the figure) is applied to the guide roller 823 from the gear chamber Sb side toward the outer diameter in the direction of the diameter line Lr, the head 820 moves toward the outer diameter via the driven link 821 that supports the guide roller 823, compressing the spring 83 between it and the cover 81. As a result, the head 820 is positioned offset from the oil passage 165, and the valve body 82 opens. This allows the flow of oil OL in the oil passage 165 to be permitted (see Figure 4).

[0071] Furthermore, when no external force is acting on the guide roller 823 from the gear chamber Sb side, the biasing force of the spring 83 maintains the head 820 in contact with the second region 852 of the housing hole 85. As a result, the head 820 is positioned to overlap with the oil passage 165, and the valve body 82 closes. This restricts the flow of oil OL in the oil passage 165 (see Figure 5).

[0072] In this embodiment, a cam portion 67 for applying an external force to the valve body 82 of the valve 8 is provided in the differential case 60. As shown in Figure 2, the differential case 60 is provided with a cam portion 67 on the outer circumference of the wall portion 66. The cam portion 67 is a single rib provided in a direction along the circumferential direction around the rotation axis X3.

[0073] As shown in Figure 3, the cam portion 67 is provided on one wall portion 66 and the other wall portion 66 on either side of the window portion 65 in the circumferential direction around the rotation axis X3. The cam portion 67 is positioned to overlap with the valve 8 in the radial direction of the rotation axis X3. As shown in Figure 6, the protrusion height H of the cam portion 67 from the wall portion 66 is set to be greater than the hole diameter D1 of the oil passage 165 (H>D1).

[0074] As shown in Figures 4 and 5, when viewed from the direction of the rotation axis X3, the wall portion 66 and the cam portion 67 form an arc shape surrounding the rotation axis X3. The cam portion 67 is provided along the entire length of the wall portion 66 in the circumferential direction around the rotation axis X3. When the differential case 60 rotates, the cam portion 67 and the window portion 65 alternately face the valve body 82 of the valve 8.

[0075] In the circumferential direction around the rotation axis X3, one end 67a and the other end 67b of the cam portion 67 are flat surfaces along straight lines Lm1 and Lm2 parallel to the diameter line Lr. The outer circumferential surface 67c of the cam portion 67 is a curved surface along a virtual circle Im1 centered on the rotation axis X3. The angular range θ from one end 67a to the other end 67b of the cam portion 67 in the circumferential direction is approximately consistent with the angular range from the valve body 82 to the discharge hole 167 (θ ≈ 90°).

[0076] Therefore, when the valve body 82 faces the cam portion 67, the discharge hole 167 of the oil passage 165 faces the window portion 65 (see Figure 4). Also, when the valve body 82 faces the window portion 65, the discharge hole 167 of the oil passage 165 faces the cam portion 67 (wall portion 66) (see Figure 5).

[0077] As shown in Figure 5, when the valve body 82 is facing the window portion 65, the biasing force of the spring 83 presses the head portion 820 against the second region 852 of the housing hole 85, blocking the oil passage 165. In this state, the guide roller 823 is located within the ring-shaped region R through which the cam portion 67 passes. Therefore, the cam portion 67 periodically contacts the guide roller 823.

[0078] For example, when a vehicle equipped with unit 1 is moving forward, the differential case 60 rotates in one direction (clockwise CW, see Figure 2) around the rotation axis X3. In the following explanation, the operation of the valve 8 will be described using the case where the differential case 60 rotates clockwise (CW) around the rotation axis X3 as an example.

[0079] Figure 8 illustrates the operation of valve 8 when the vehicle is moving forward. Figures 8(a) to (d) sequentially show the process by which the valve body 82 of valve 8 opens and closes in conjunction with the rotation of the differential case 60.

[0080] As shown in Figure 8(a), when the differential case 60 rotates, the cam portion 67 approaches the valve body 82 of the valve 8 from above, and one end 67a comes into contact with the guide roller 823. In conjunction with this, the window portion 65 faces the discharge hole 167.

[0081] At the position where one end 67a of the cam portion 67 contacts the guide roller 823, the one end 67a is inclined to be positioned upward as it approaches the outer peripheral surface 67c. Therefore, as the differential case 60 rotates, one end 67a of the cam portion 67 presses the guide roller 823 outward against the biasing force of the spring 83 (see the rightward arrow in the figure). As a result, an external force acts on the valve body 82 in the direction toward the outer diameter.

[0082] The guide roller 823 moves toward the outer diameter while rotating around the rotation axis Xa (see Figure 7). The head 820 moves toward the outer diameter (opens the valve) while compressing the spring 83 via the driven link 821 that supports the guide roller 823. As a result, the head 820 moves away from the oil passage 165, allowing the flow of oil OL in the oil passage 165 to be permitted, and the discharge of oil OL from the discharge hole 167 toward the window 65 begins.

[0083] As shown in Figure 8(b), as the differential case 60 rotates further, the guide roller 823 of the valve body 82 rides up onto the outer circumferential surface 67c of the cam portion 67. The window portion 65 remains facing the discharge hole 167. The position where the guide roller 823 rides onto the outer circumferential surface 67c of the cam portion 67 is the position where the head portion 820 is furthest from the oil passage 165. In other words, the protrusion height H of the cam portion 67 (see Figure 6) corresponds to the stroke amount of the valve body 82.

[0084] As described above, the protruding height H of the cam portion 67 is set to be greater than the hole diameter D1 of the oil passage 165 (H>D1, see Figure 6). Therefore, when the guide roller 823 rides onto the outer circumferential surface 67c of the cam portion 67, the head portion 820 is completely offset from the oil passage 165. As a result, while the guide roller 823 rides on the outer circumferential surface 67c of the cam portion 67, the cam portion 67 presses the valve body 82 outward with a constant force. Therefore, oil OL is stably discharged from the discharge hole 167 to the window portion 65, lubricating the bevel gear 62 and the like.

[0085] As shown in Figure 8(c), as the differential case 60 rotates further, the guide roller 823 of the valve body 82 moves from the outer circumferential surface 67c of the cam portion 67 to the other end 67b.

[0086] At the point where the other end 67b of the cam portion 67 and the guide roller 823 come into contact, the other end 67b is inclined to be positioned upward as it moves toward the inner diameter. Therefore, as the differential case 60 rotates, the guide roller 823 is pushed back toward the inner diameter by the biasing force of the spring 83, while coming into contact with the other end 67b of the cam portion 67 (see leftward arrow in the figure). The guide roller 823 moves toward the inner diameter while rotating around the rotation axis Xa (see Figure 7).

[0087] As a result, the head 820 of the valve body 82 moves closer to the oil passage 165, narrowing the cross-sectional area of ​​the oil passage 165 and reducing the amount of oil OL supplied from the discharge hole 167 to the window 65.

[0088] As shown in Figure 8(d), when the differential case 60 rotates further, the valve body 82 detaches from the other end 67b of the cam portion 67 and faces the window portion 65. In conjunction with this, the discharge hole 167 faces the cam portion 67 (wall portion 66).

[0089] When the valve body 82 is facing the window portion 65, no external force acts on the valve body 82 in the direction toward the outer diameter from the differential case 60; only the biasing force of the spring 83 acts on it. As a result, the head portion 820 of the valve body 82 is pressed against the second region 852 of the housing hole 85 (the valve is closed). As a result, the oil passage 165 becomes blocked by the head 820, restricting the flow of oil OL in the oil passage 165, and stopping the discharge of oil OL from the discharge hole 167.

[0090] Therefore, the valve 8 is designed to reliably switch between supplying and stopping the supply of oil OL in conjunction with the movement of the cam portion 67 (wall portion 66).

[0091] Subsequently, the valve body 82 repeatedly contacts and disengages from the cam portion 67 in conjunction with the rotation of the differential case 60. In this embodiment, oil OL is discharged twice from the discharge hole 167 for each rotation of the differential case 60.

[0092] Therefore, by providing the valve 8, it is possible to control the discharge (supply) of oil OL so that when the discharge hole 167 and the wall portion 66 are facing each other during the rotation of the differential case 60, the discharge (supply) of oil OL is stopped, and when the discharge hole 167 and the window portion 65 are facing each other, the discharge of oil OL is performed.

[0093] In this way, by intermittently discharging oil OL toward the differential case 60, the discharge of unnecessary oil OL that does not contribute to lubrication can be reduced. For example, as shown in Figure 1, when oil OL is not being discharged to the differential case 60, the electric oil pump EOP only needs to provide enough driving force to supply oil OL to the motor 2 and each bearing Bm, B4 to B6. In this case, the load on the electric oil pump EOP is reduced compared to when oil OL is supplied to all of the differential gear 6, motor 2, and bearings Bm, B4-B6. Therefore, the power consumption of the electric oil pump EOP is reduced, and more efficient operation can be achieved.

[0094] In this embodiment, an electric oil pump (EOP) was used as an example, but this can also be applied to an oil pump driven by the rotation of a motor 2 (see Figure 1) (a mechanical oil pump). The intrinsic discharge volume of a mechanical oil pump is proportional to the pump drive torque (the drive torque of motor 2). By reducing the discharge of unnecessary oil (OL) in a mechanical oil pump and decreasing the intrinsic discharge volume, the load on motor 2 can be reduced. This reduces the power consumption of motor 2.

[0095] The following are examples of Unit 1 in a certain aspect of the present invention. (1) Unit 1 is Electric oil pump EOP (oil pump), The discharge hole 167 (nozzle) of the oil passage 165 connected downstream of the electric oil pump EOP, A differential gear 6 having a differential case 60 having a window portion 65 through which oil OL is supplied from a discharge hole 167, and a wall portion 66 adjacent to the window portion 65, The differential case 60 includes a valve 8 that stops the supply of oil OL from the discharge hole 167 when the discharge hole 167 and the wall portion 66 face each other during rotation of the differential case 60.

[0096] When oil OL is discharged when the discharge hole 167 and the wall portion 66 are facing each other, the oil OL is repelled by the wall portion 66. In this case, the power consumption (energy) required to operate the electric oil pump EOP is wasted. Therefore, by configuring it as described above and stopping the supply of oil OL when the discharge hole 167 faces the wall portion 66, the power consumption of the electric oil pump EOP can be reduced and efficient operation can be achieved.

[0097] (2) The valve 8 is configured to open when the wall portion 66 and the valve 8 face each other, allowing oil to be supplied from the electric oil pump EOP to the discharge hole 167. Valve 8 is configured to close when the window 65 and valve 8 face each other, thereby stopping the supply of oil from the electric oil pump EOP to the discharge hole 167.

[0098] With this configuration, the supply and stop of oil OL can be switched in conjunction with the movement of the wall section 66 and the window section 65. Therefore, the electric oil pump EOP can be operated more efficiently.

[0099] (3) The valve 8 has a valve body 82 that opens and closes the oil passage 165 and a spring 83 that provides a biasing force to the valve body 82. The differential case 60 has a cam portion 67 on the outer circumference of the wall portion 66. When the valve body 82 faces the cam portion 67 of the wall portion 66, it is pressed by the cam portion 67, compressing the spring 83 and opening the valve. When the valve body 82 faces the window portion 65, it closes due to the biasing force of the spring 83.

[0100] With this configuration, the supply and cessation of oil OL can be reliably switched in conjunction with the movement of the cam portion 67 (wall portion 66).

[0101] (Variation 1) In the valve 8 according to the embodiment described above, a mechanism was illustrated in which the valve is opened by pressing the valve body 82 with the cam portion 67. However, the mechanism for opening the valve 8 is not limited to the embodiment described above. For example, a mechanism that opens the valve using the repulsive force of a magnet may also be used.

[0102] Figure 9 is a diagram illustrating unit 1A according to modified example 1. Figure 10 is a diagram illustrating unit 1A according to modification 1. Figure 10 shows the differential gear 6A shown in Figure 9 rotated 90° around the rotation axis X3. In the following description, components similar to those in the embodiment will be denoted by the same reference numerals, and detailed explanations will be omitted.

[0103] As shown in Figure 9, the valve 8A of unit 1A according to modified example 1 has a valve body 82A made of a spherical magnet. The valve body 82A is housed in the housing hole 85 with the north pole region 82N facing inward and the south pole region 82S facing outward. The south pole region of the valve 8A is fixed to the tip of a spring 83, for example, by welding. In the housing hole 85, the spring 83 is provided between the valve body 82A and the cover portion 81.

[0104] Furthermore, in the differential case 60A of unit 1A according to modification 1, ribs 68 are provided on the outer circumference of the wall portion 66. Viewed from the direction of the rotation axis X3, the wall portion 66 and the rib 68 form an arc shape surrounding the rotation axis X3. The rib 68 is provided along the entire length of the wall portion 66 in the circumferential direction around the rotation axis X3. Therefore, when the differential case 60A rotates, the rib 68 and the window portion 65 alternately face the valve body 82A of the valve 8A.

[0105] The rib 68 is made of magnets. The rib 68 is fixed to the outer circumference of the wall portion 66 with the north pole region 68N facing outwards and the south pole region 68S facing inwards. Therefore, when the rib 68 is positioned opposite the valve body 82A, the north pole side region 68N of the rib 68 and the north pole side region 82N of the valve body 82A come into close proximity to each other.

[0106] In this case, a repulsive force acts on the valve body 82A in a direction that is opposed to the magnetic force of the rib 68 (see the rightward arrow in the figure). The valve body 82A moves outward (opens) while compressing the spring 83 due to the repulsive force. As a result, the valve body 82A moves away from the oil passage 165, allowing the flow of oil OL in the oil passage 165 to be permitted, and the discharge of oil OL from the discharge hole 167 toward the window 65 begins.

[0107] Furthermore, as shown in Figure 10, when the valve body 82A is facing the window portion 65, no repulsive force acts on the valve body 82A, and only the biasing force of the spring 83 acts on it. As a result, the valve body 82A is pressed against the second region 852 of the housing hole 85 (closed). As a result, the oil passage 165 is blocked by the valve body 82A, restricting the flow of oil OL in the oil passage 165. This stops the discharge of oil OL from the discharge hole 167. Therefore, the valve 8A is designed to reliably switch between supplying and stopping the supply of oil OL in conjunction with the movement of the rib 68 (wall portion 66).

[0108] In Modification Example 1, the case where the north poles (82N, 68N) of the valve body 82A and the rib 68 face each other is illustrated, but the invention is not limited to this embodiment. The south poles (82S, 68S) of the valve body 82A and the rib 68 may face each other.

[0109] The unit 1A relating to the modified example 1 has the following configuration. (4) The valve 8A has a valve body 82A that opens and closes the oil passage 165 and a spring 83 that provides a biasing force to the valve body 82A. The differential case 60A has ribs 68 on the outer circumference of the wall portion 66. The valve body 82A and rib 68 are made of magnets. When the valve body 82A of valve 8A faces the rib 68 of the wall portion 66, it repels the magnetic force of the rib 68 and opens. When the valve body 82A of valve 8A faces the window portion 65, it closes due to the biasing force of the spring 83.

[0110] With this configuration, the supply and cessation of oil OL can be reliably switched in conjunction with the movement of the wall portion 66.

[0111] (Modification 2) In the embodiments and modification 1 described above, valves 8 and 8A are illustrated as being opened by applying an external force to the valve bodies 82 and 82A from the wall portion 66 side of the differential case 60. However, the invention is not limited to these embodiments. For example, valve 8B may be opened by electronic control.

[0112] Figure 11 is a diagram illustrating unit 1B related to modified example 2. As shown in Figure 11, in the differential gear 6B of unit 1B according to the modified example 2, the differential case 60B can be made in which the cam portion 67 (see Figure 4) and rib 68 (see Figure 9) are not provided on the wall portion 66.

[0113] Furthermore, the oil passage 165A of unit 1B is positioned above the diameter line Lr, oriented along a straight line Lp parallel to the diameter line Lr. An electric oil pump EOP is connected to one end of the oil passage 165A, and a discharge hole 167 is connected to the other end.

[0114] The valve 8B of unit 1B includes a sensor 86 that detects the rotation of the differential case 60B, a solenoid valve 87 that opens and closes the oil passage 165A, and a control unit 88 that receives signals from the sensor 86 and controls the drive of the solenoid valve 87.

[0115] The sensor 86 is provided on the cylindrical wall portion 161 surrounding the differential case 60B. The sensor 86 is exposed on the inner circumferential surface 161a of the cylindrical wall portion 161 at the position where the diameter lines Lr intersect. The sensor 86 can be, for example, a known Hall sensor.

[0116] When the wall portion 66 is positioned opposite the sensor 86, the magnetic field of the Hall element (not shown) of the sensor 86 changes. The sensor 86 detects the rotation of the differential case 60B from the change in the magnetic field of the Hall element and transmits the detection result to the control unit 88.

[0117] The control unit 88 includes a processing unit 881 that processes information from the sensor 86 and a command unit 882 that commands the opening and closing of the solenoid valve 87. The processing unit 881 receives a signal from the sensor 86 and obtains the following information. (a) The wall portion 66 of the differential case 60B is positioned opposite the sensor 86, and the window portion 65 is positioned opposite the discharge hole 167. (b) Rotational speed of differential case 60B (number of times the wall portion 66 crosses the sensor 86)

[0118] The command unit 882 is electrically connected to the solenoid valve 87. Based on the information (a) and (b) obtained by the processing unit 881, the command unit 882 commands the opening and closing of the solenoid valve 87.

[0119] Here, the command unit 882 can open and close the solenoid valve 87 each time the wall portion 66 crosses the sensor 86, based solely on the information in (a). That is, similar to the embodiment and modification 1 described above, oil OL can be discharged twice for each rotation of the differential case 60B.

[0120] However, when valve 8B is controlled electronically to open, the opening and closing cycle of solenoid valve 87 may lag behind the rotational cycle of differential case 60B. Therefore, the command unit 882 can combine the information from (a) and the information from (b) to delay the opening and closing cycle of the solenoid valve 87 with respect to the rotational cycle of the differential case 60B. For example, the control unit 882 can open the solenoid valve 87 once when the differential case 60B rotates three (or more) times. This makes it possible to operate the electric oil pump (EOP) more efficiently while implementing smooth electronic control.

[0121] Furthermore, when the vehicle is moving in a straight line, there is no difference in rotation between the left and right drive wheels WH (see Figure 1), so the frequency of supplying oil OL to the bevel gear 62, side gear 63, and pinion mate shaft 64 may be relatively low. Therefore, by electronically controlling valve 8B, the frequency of opening of solenoid valve 87 can be controlled according to the driving conditions. For example, when the vehicle is moving straight, the solenoid valve 87 can be opened once for every 100 rotations of the differential case 60B, and when the vehicle is turning, the solenoid valve 87 can be opened once for every 3 rotations of the differential case 60B. Furthermore, whether the vehicle is moving straight or turning can be determined from known steering sensors, etc. The command unit 882 of the control unit 88 can combine the information (a) and (b) identified by the processing unit 881 with the information obtained from the steering sensors to set the frequency of opening the solenoid valve 87 in more detail. This makes it possible to achieve both reduced power consumption and improved lubrication performance in the electric oil pump (EOP).

[0122] The unit 1B relating to the modified example 2 has the following configuration. (5) The valve 8B includes a sensor 86 that detects the rotation of the differential case 60B, and a control unit 88 that opens and closes the solenoid valve 87 based on the detection result of the sensor 86. The control unit 88 opens the solenoid valve 87 to supply oil OL to the window portion 65 once for each of the multiple rotations of the differential case 60B.

[0123] For example, when electronically controlling valve 8B to open solenoid valve 87, the opening and closing cycle of solenoid valve 87 may lag behind the rotational cycle of differential case 60B. Therefore, by configuring it as described above and delaying the opening and closing cycle of the solenoid valve 87 relative to the rotation cycle of the differential case 60B, it becomes possible to operate the electric oil pump EOP more efficiently while performing smooth electronic control.

[0124] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments shown. It can be modified as appropriate within the scope of the technical idea of ​​the invention. [Explanation of Symbols]

[0125] 1, 1A, 1B: Unit 6: Differential Gear 8, 8A, 8B: Valves 12: Gear Case 16:Bulging wall part 60, 60A, 60B: Differential Case 62: Bevel gear 63: Side gear 64: Pinion Mate Shaft 65: Window section 66:Wall 67: Cam section 67a: one end 67b: Other end 67c: Outer surface 68: Rib 81: Lid part 82, 82A: Valve body 83: Spring 85: Enclosure hole 86: Sensor 87: Solenoid valve 88: Control Unit 161: Cylinder wall 161a: Inner surface 165: Oil road 167: Discharge hole (nozzle) 820: Head 821: dependent clause 823: Guide roller EOP: Electric Oil Pump OL: Oil X, X1, X2, X3: Rotation axis

Claims

1. oil pump and A nozzle connected downstream of the oil pump, A differential gear having a differential case having a window portion through which oil is supplied from the nozzle, and a wall portion adjacent to the window portion, A unit comprising: a valve that stops the supply of oil from the nozzle when the nozzle and the wall face each other during the rotation of the differential case.

2. In claim 1, The valve is configured to open when the wall portion and the valve face each other, thereby allowing oil to be supplied from the oil pump to the nozzle.

3. In claim 2, The valve is a unit that opens when pressed against the wall.

4. In claim 2, The valve is a unit that opens in repulsion from the magnetic force on the wall side.

5. In claim 1, The valve is a unit that opens to supply oil to the window once for each multiple rotations of the differential case.

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