Drive device

Abstract

The invention provides a drive device capable of maintaining the estimation accuracy of the temperature of a clutch part without complicating the structure of a housing. A drive device (1) is provided with: a housing (3) that accommodates lubricating oil; a pair of rotating members (5, 7) accommodated in the housing (3) so as to be capable of rotating relative to each other; a clutch unit (9) that clutches power transmitted between the pair of rotating members (5, 7); and a driver (11) housed in the housing (3) and having an electric element (39) for operating the clutch unit (9), the electric element (39) being provided with a temperature sensor (13) for detecting the temperature inside the housing (3).

Description

Technical Field

[0001] This invention relates to a driving device. Background Technology

[0002] A known drive device includes a housing for containing lubricating oil, a gearbox comprising a pair of rotating parts rotatably housed within the housing, and a side gear. It also includes a clutch portion for engaging and disengaging power transmitted between the gearbox and the side gear. Furthermore, it includes a driver housed within the housing, and has an electromagnetic coil serving as an electrical element for actuating the clutch portion. (See Patent Document 1).

[0003] In this drive unit, the electromagnetic coil is electrically connected to a controller that controls the energization of the electromagnetic coil via a lead extending to the outside of the housing. In such a drive unit, the engagement / disengagement state of the clutch is controlled by the energization state of the electromagnetic coil controlled by the controller.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2004-2211899 Summary of the Invention

[0007] Technical issues

[0008] However, in the drive device described in Patent Document 1, the temperature of the clutch is measured, and the clutch engagement state is controlled based on the temperature of the clutch, thereby stabilizing the clutch engagement characteristics. However, since the clutch is a rotating component, a temperature sensor electrically connected to the controller via leads cannot be directly disposed in the clutch.

[0009] Therefore, temperature sensors are positioned on the surface near the clutch portion outside the housing, which is a stationary component, or in the lubricating oil reservoir inside the housing, to estimate the temperature of the clutch portion. However, when the temperature sensor is positioned outside the housing, the placement is sometimes limited by surrounding components, and ensuring sufficient space for the temperature sensor complicates the housing structure. Furthermore, the temperature estimation accuracy of the clutch portion inside the housing is lower when the surface temperature is outside the housing. On the other hand, when the temperature sensor is positioned in the lubricating oil reservoir inside the housing, it is necessary to consider the lubrication environment of the lubricating oil, or to provide a structure for extending new leads on the housing.

[0010] This invention was made in view of the problems existing in the prior art. The object of this invention is to provide a drive device that can maintain the estimated accuracy of the temperature of the clutch without complicating the structure of the housing.

[0011] Technical solution

[0012] The drive device of this embodiment includes: a housing containing lubricating oil; a pair of rotating parts rotatably housed in the housing; a clutch that engages power transmitted between the pair of rotating parts; and a drive housed in the housing and having an electrical component that actuates the clutch, wherein the electrical component is provided with a temperature sensor that detects the temperature inside the housing.

[0013] The effects of the invention

[0014] According to the present invention, a drive device is provided that can maintain the estimated accuracy of the temperature of the clutch without complicating the structure of the housing. Attached Figure Description

[0015] Figure 1 This is a cross-sectional view of the drive device according to the first embodiment.

[0016] Figure 2 This is a cross-sectional view of the drive device according to the second embodiment.

[0017] Figure Labels

[0018] 1, 101: Drive unit; 3: Housing; 5: First rotating component; 7: Second rotating component; 9, 105: Clutch; 11, 107: Driver; 13, 109: Temperature sensor; 39, 139: Electrical component; 41, 141: Electric motor; 55, 149: Stator; 57, 151: Rotor; 111: Differential gearbox (rotating component); 119: Side gear (rotating component); L: Oil level. Detailed Implementation

[0019] The driving device of this embodiment will now be described in detail with reference to the accompanying drawings. Furthermore, the dimensions in the drawings are exaggerated for ease of explanation and may sometimes differ from the actual scale.

[0020] (First embodiment)

[0021] will utilize Figure 1 The first embodiment will be described.

[0022] like Figure 1As shown, the drive unit 1 of this embodiment is, for example, disposed between the input-side mechanism and the output-side mechanism in the power transmission path of the vehicle. The drive unit 1 has a clutch 9 that disengages the driving force transmitted from the input-side mechanism to the output-side mechanism. When the clutch 9 is engaged, the drive unit 1 can transmit the driving force from the input-side mechanism to the output-side mechanism. On the other hand, when the clutch 9 is disengaged, the drive unit 1 cuts off the transmission of the driving force from the input-side mechanism to the output-side mechanism.

[0023] like Figure 1 As shown, the drive unit 1 includes a housing 3, a first rotating component 5 and a second rotating component 7 as a pair of rotating components, a clutch 9, a driver 11, and a temperature sensor 13.

[0024] The housing 3 is a stationary component fixed to the vehicle and consists of multiple segmented parts. These segmented parts are secured by multiple bolts, thereby forming an internal space to accommodate each component. The housing 3 contains lubricating oil that lubricates and cools the sliding parts of the components or the meshing parts of gears.

[0025] The first rotating component 5 is shaped like a shaft, with the portion protruding from the outer casing 3 being solid and the portion inside the outer casing 3 being hollow. The first rotating component 5 is rotatably supported on the outer casing 3 via a bearing 15. A sealing component 17 is disposed radially between the first rotating component 5 and the outer casing 3 to divide the interior and exterior of the outer casing 3.

[0026] A spline-shaped connecting portion 19 is formed on the outer periphery of the portion of the housing 3 of the first rotating member 5 that is rotatably connected integrally with the mechanism on the input side. The first rotating member 5 receives driving force from the mechanism on the input side via the connecting portion 19 and transmits the driving force to the second rotating member 7 via the clutch portion 9.

[0027] The second rotating member 7 is formed as an axis parallel to the axis of the first rotating member 5, and is partially open on the outer side of the housing 3 and partially closed inside the housing 3, forming a hollow structure. The second rotating member 7 is rotatably supported on the housing 3 via a bearing 21, and is rotatably supported relative to the first rotating member 5 via a bearing 23. A sealing member 25 is disposed radially between the second rotating member 7 and the housing 3 to divide the interior and exterior of the housing 3.

[0028] A spline-shaped connecting portion 27 is formed on the inner circumference of the second rotating member 7, which is integrally and rotatably connected to the mechanism on the output side. The second rotating member 7 transmits the driving force transmitted via the clutch portion 9 to the mechanism on the output side via the connecting portion 27.

[0029] The clutch section 9 includes a clutch hub 29, a clutch housing 31, and multiple clutch plates.

[0030] The clutch hub 29 is cylindrical and disposed on the outer periphery of the first rotating member 5. The clutch hub 29 is fixed to the end of the first rotating member 5 by means of welding or other joining methods, thereby being rotatably fixed integrally with the first rotating member 5. A spline-shaped engagement portion is formed on the outer periphery of the clutch hub 29.

[0031] The clutch housing 31 is formed as a bottomed cylindrical shape, and the cylindrical portion is disposed on the outer peripheral side of the clutch hub 29. In the clutch housing 31, the portion forming the bottom is formed by a component continuous with the outer periphery of the second rotating component 7 and rotates integrally with the second rotating component 7. A thrust bearing 33 is disposed between the clutch housing 31 and the outer housing 3 along the axial direction. This thrust bearing 33 allows rotation of the clutch housing 31 and receives axial movement of the clutch housing 31. A spline-shaped engagement portion is formed on the inner periphery of the clutch housing 31.

[0032] The clutch plates consist of multiple inner clutch plates and multiple outer clutch plates. The multiple inner clutch plates are axially movable and can be rotatably engaged with the first rotating member 5 in the engagement portion of the clutch hub 29. The multiple outer clutch plates are arranged alternately axially relative to the multiple inner clutch plates, and are axially movable and can be rotatably engaged with the second rotating member 7 in the engagement portion of the clutch housing 31.

[0033] The clutch portion 9, which has multiple clutch plates, is a control-type friction clutch that can perform intermediate control of the transmitted torque through sliding friction. At the ends of the multiple clutch plates, there are pressing plates that can move axially and are integrally rotatably engaged with the engaging portion of the clutch housing 31. By operating the drive 11, the pressing plates move axially to press the multiple clutch plates.

[0034] The drive 11 has a cam mechanism 35, a speed change mechanism 37, and an electric motor 41 as an electrical component 39.

[0035] The cam mechanism 35 is a ball cam mechanism that converts the rotational force generated by the speed change mechanism 37 into an axial operating force. The cam mechanism 35 includes a fixed ring 43, a cam ring 45, and a cam ball 47.

[0036] The fixed ring 43 is prevented from rotating by the housing 3 via a locking portion on its outer periphery, and its axial movement is restricted. The cam ring 45 is axially opposed to the fixed ring 43 and is axially movable and rotatable. A thrust bearing 49 is disposed between the cam ring 45 and the pressing plate of the clutch 9 in the axial direction. This thrust bearing 49 allows relative rotation between the cam ring 45 and the pressing plate of the clutch 9 and transmits the axial movement of the cam ring 45 to the pressing plate. Multiple cam surfaces are formed circumferentially on the opposing surfaces of the fixed ring 43 and the cam ring 45 in the axial direction.

[0037] Cam balls 47 are respectively disposed between multiple cam surfaces of the fixed ring 43 and the cam ring 45. The cam balls 47 cause a rotational difference between the fixed ring 43 and the cam ring 45 through the rotation of the cam ring 45, thereby generating a cam thrust that moves the cam ring 45 in the connection direction of the clutch part 9.

[0038] The speed change mechanism 37 is a planetary gear mechanism that reduces the rotation speed of the electric motor 41. The speed change mechanism 37 includes a gear portion formed on the inner circumference of the fixed ring 43, a gear portion formed on the inner circumference of the cam ring 45, a planetary gear 51, and a planet carrier 53.

[0039] The number of teeth on planetary gear 51 is different from the number of teeth on the gear portion of fixed ring 43 and the gear portion of cam ring 45, and planetary gear 51 meshes with the gear portion of fixed ring 43 and the gear portion of cam ring 45. Planetary carrier 53 rotatably supports planetary gear 51. Planetary carrier 53 is integrally mounted with rotor 57 of electric motor 41 and rotates integrally with rotor 57 as rotor 57 rotates. Speed ​​change mechanism 37 reduces the rotation from electric motor 41, causing cam ring 45 of cam mechanism 35 to rotate.

[0040] The electric motor 41 has a stator 55 and a rotor 57.

[0041] The stator 55 is formed in a ring shape and includes a magnetic core and an electromagnetic coil. The magnetic core is made of magnetic material, and multiple magnetic cores are arranged circumferentially and prevented from rotating by the housing 3. The electromagnetic coil is wound around the outer periphery of the multiple magnetic cores a predetermined number of times and generates an axial magnetic flux when energized. Leads (not shown) extending from the housing 3 to the outside are electrically connected to the ends of the electromagnetic coils. The leads are electrically connected to a controller (not shown) that controls the operation of various mechanisms mounted on the vehicle.

[0042] The rotor 57 is made of magnetic material and is formed in a ring shape. The rotor 57 is restricted from axial movement relative to the housing 3 by a limiting portion formed on its outer periphery, and its inner periphery is rotatably supported relative to the first rotating member 5 via a bearing 59. The rotor 57 is axially opposed to the stator 55 through a small gap allowing magnetic flux to pass through. Furthermore, to increase the magnetic flux transmission area, multiple protrusions are formed on the axially opposed surfaces of the rotor 57 and stator 55 in a radially staggered arrangement. The rotor 57 rotates using magnetic flux generated by energizing the electromagnetic coils of the stator 55.

[0043] In such a drive 11, in the electric motor 41, current controlled by a controller is energized to the electromagnetic coil of the stator 55 according to the desired tightening torque obtained at the clutch 9. By energizing the electromagnetic coil of the stator 55, the rotor 57 rotates, is decelerated by the transmission mechanism 37, and is transmitted to the cam mechanism 35. In the cam mechanism 35, the cam ring 45 rotates due to the rotation from the transmission mechanism 37, creating a rotational difference between the fixed ring 43 and the cam ring 45. Due to this rotational difference between the fixed ring 43 and the cam ring 45, the cam ball 47 moves circumferentially between the cam surfaces. The movement of the cam ball 47 generates an axial cam thrust, causing the cam ring 45 to move along the connection direction of the clutch 9. The movement of the cam ring 45 presses multiple clutch plates via a press plate, and the clutch 9 engages. The engagement of the clutch 9 allows power transmission between the first rotating component 5 and the second rotating component 7.

[0044] Temperature sensor 13 is disposed inside the housing 3 within the stator 55 of the electric motor 41, which is an electrical component 39. Alternatively, temperature sensor 13 can be disposed on the stator 55 side; for example, it can be disposed on the mounting portion of the stator 55 fixed to the housing 3. By disposing of temperature sensor 13 on the stator 55 side, it can be treated as a sub-component of the driver 11, improving assemblability. Furthermore, temperature sensor 13 can be disposed, for example, on the mounting portion of the housing 3 that fixes the stator 55. A lead (not shown) extending to the outside of the housing 3 is electrically connected to temperature sensor 13. The lead is electrically connected to the controller.

[0045] Temperature sensor 13 detects the internal temperature of housing 3 and outputs it to controller. The controller estimates the temperature of clutch 9 based on the temperature detected by temperature sensor 13, and controls the energization of the electromagnetic coil according to the temperature of clutch 9. In estimating the temperature of clutch 9 by the controller, placing temperature sensor 13 inside housing 3 significantly improves estimation accuracy compared to placing temperature sensor 13 on the external surface of housing 3.

[0046] The leads of the temperature sensor 13 converge with the leads of the electromagnetic coil and are led out from the lead-out portion provided in the housing 3 to the outside of the housing 3. Therefore, there is no need to reconfigure the structure of the housing 3 to lead out the temperature sensor 13, and the structure of the housing 3 is not complicated. In addition, by providing the temperature sensor 13 on the electrical component 39 disposed inside the housing 3, there is no need to consider the lubrication environment of the lubricating oil as when the temperature sensor 13 is reconfigured in the lubricating oil reservoir.

[0047] The temperature sensor 13 is disposed below the oil level L of the lubricating oil inside the housing 3. By disposing the temperature sensor 13 below the oil level L, the temperature sensor 13 is disposed within the lubricating oil. Therefore, the temperature sensor 13 can more accurately detect the temperature of the lubricating oil, and can further improve the estimation accuracy of the temperature of the clutch 9.

[0048] Temperature sensor 13 is disposed on the outside of stator 55, outside of the fixing part of stator 55, and outside of the fixing part of housing 3, for example, exposed inside housing 3. Temperature sensor 13 exposed inside housing 3 is an oil-resistant temperature sensor that can come into contact with lubricating oil. Because temperature sensor 13 comes into contact with lubricating oil, the temperature of lubricating oil can be detected more accurately, and the estimation accuracy of the temperature of clutch 9 can be further improved.

[0049] Here, the temperature sensor 13 can be disposed inside the stator 55, the fixing part of the stator 55, or the fixing part of the housing 3, on the stator 55 side, for example, without being exposed inside the housing 3. Since the temperature sensor 13 is not exposed inside the housing 3, it cannot come into contact with lubricating oil. Therefore, the temperature sensor 13 does not need to be oil-resistant, which reduces its cost. Furthermore, because the temperature sensor 13 is disposed inside the stator 55 side, it will not interfere with surrounding components, and its durability can be improved.

[0050] This drive unit 1 includes a housing 3 for containing lubricating oil, and a first rotating member 5 and a second rotating member 7, which are rotatably housed in the housing 3 as a pair of rotating components. It also includes a clutch 9 for engaging and disengaging the power transmitted between the first rotating member 5 and the second rotating member 7, and a driver 11 housed in the housing 3 and equipped with an electrical component 39 for actuating the clutch 9. Furthermore, the electrical component 39 is equipped with a temperature sensor 13 for detecting the temperature inside the housing 3.

[0051] Since the temperature sensor 13 is housed within the electrical component 39 housed in the housing 3, it is positioned inside the housing 3. Therefore, compared to the case where the temperature sensor 13 is positioned on the outer surface of the housing 3, the accuracy of temperature estimation for the clutch 9 can be significantly improved. Furthermore, by positioning the temperature sensor 13 within the electrical component 39, the leads of the temperature sensor 13 and the leads of the electrical component 39 can be converged and led out from the housing 3 to the outside. Therefore, there is no need to restructure the housing 3 to route the leads of the temperature sensor 13, thus avoiding complicating the structure of the housing 3. In addition, by positioning the temperature sensor 13 within the electrical component 39 housed inside the housing 3, the lubrication environment of the lubricating oil does not need to be considered as when the temperature sensor 13 is repositioned within the lubricating oil reservoir.

[0052] Therefore, in such a drive device 1, the structure of the housing 3 is not complicated, and the estimated accuracy of the temperature of the clutch 9 can be maintained.

[0053] In addition, the electrical component 39 is composed of an electric motor 41, which has a stator 55 fixed to the housing 3 and a rotor 57 that rotates by energizing the stator 55. Furthermore, a temperature sensor 13 is provided on the stator 55 side.

[0054] By placing the temperature sensor 13 on the stator 55 side, the temperature sensor 13 can be treated as a component of the driver 11, which improves assemblability.

[0055] In addition, the temperature sensor 13 is positioned below the oil level L of the lubricating oil.

[0056] Therefore, by arranging a temperature sensor 13 in the lubricating oil, the temperature sensor 13 can detect the temperature of the lubricating oil more accurately and further improve the estimation accuracy of the temperature of the clutch 9.

[0057] In addition, the temperature sensor 13 can be configured to contact the lubricating oil.

[0058] Therefore, since the temperature sensor 13 is in contact with the lubricating oil, the temperature of the lubricating oil can be detected more accurately, and the estimation accuracy of the temperature of the clutch 9 can be further improved.

[0059] In addition, the temperature sensor 13 is disposed inside the stator 55 side so that it cannot come into contact with the lubricating oil.

[0060] Therefore, the temperature sensor 13 does not need to be oil-resistant, which reduces the cost of the temperature sensor 13. In addition, since the temperature sensor 13 is disposed inside the stator 55, the temperature sensor 13 will not interfere with surrounding components, and the durability of the temperature sensor 13 can be improved.

[0061] (Second embodiment)

[0062] will utilize Figure 2 The second embodiment will be described.

[0063] like Figure 2As shown, the drive unit 101 in this embodiment is, for example, a differential device disposed between the left and right gears in the power transmission path of a vehicle. While outputting driving force from the drive source to the left and right wheel sides, the drive unit 101 allows for a rotational difference between the left and right wheels when a rotational difference occurs. The drive unit 101 has a clutch portion 105 that engages and disengages the differential between the left and right wheels. When the clutch portion 105 is engaged, the drive unit 101 locks the differential between the left and right wheels. Conversely, when the clutch portion 105 is disengaged, the drive unit 101 unlocks the differential between the left and right wheels.

[0064] like Figure 2 As shown, the drive unit 101 includes a housing (not shown), a differential mechanism 103, a clutch 105, a driver 107, and a temperature sensor 109.

[0065] Although not shown, the housing is a stationary component fixed to the vehicle and, for example, consists of multiple segmented parts. These segmented parts are secured by multiple bolts or other fastening methods, thereby forming an internal space that accommodates each component. The housing contains lubricating oil that lubricates and cools the sliding parts of the components or the meshing parts of gears.

[0066] The differential mechanism 103 includes a differential housing 111, a pinion shaft 113, a pinion 115, and a pair of side gears 117 and 119. In addition, the pair of rotating parts are the differential housing 111 and the side gears 119.

[0067] The differential case 111 is rotatably supported on the outer periphery of the protrusions 121 and 123 formed on both axial sides via bearings (not shown). A flange 125 is formed within the differential case 111 to hold a ring gear (not shown). The ring gear, fixed to the flange 125, meshes with, for example, a power transmission gear (not shown) that transmits driving force from a drive source, and rotates the differential case 111 by being driven by the input driving force. The differential case 111 houses a pinion shaft 113, a pinion 115, a pair of side gears 117 and 119, etc.

[0068] The pinion shaft 113 has one long pinion shaft and two short pinion shafts. The two ends of the long pinion shaft engage with holes formed in the differential housing 111 and are integrally driven to rotate with the differential housing 111. One end of the short pinion shaft engages with a hole formed in the middle of the long pinion shaft, and the other end engages with a hole formed in the differential housing 111, and is prevented from falling off by a pin; it is integrally driven to rotate with the differential housing 111. Pinions 115 are respectively supported on the outer end sides of the pinion shaft 113.

[0069] Multiple (four in this case) pinions 115 are arranged at equal intervals along the circumference of the differential housing 111. Each pinion 115 is supported on the end side of a pinion shaft 113 and revolves around the differential housing 111. When a rotational difference occurs between the meshing pair of side gears 117 and 119, the pinions 115 are rotatably supported on the pinion shaft 113 in a rotationally driven manner. The pinions 115 transmit the driving force input to the differential housing 111 to the pair of side gears 117 and 119.

[0070] A pair of side gears 117 and 119 are rotatably housed within a differential housing 111. The side gears 117 and 119 mesh with a pinion 115. Spline-shaped output sections 127 and 129, which output the driving force transmitted to the side gears 117 and 119, are provided on the inner circumference of the pair of side gears 117 and 119. For example, a pair of output shafts (not shown) integrally rotatably connected to the left and right wheels are integrally rotatably connected to the output sections 127 and 129.

[0071] In this differential mechanism 103, the differential of a pair of side gears 117, 119 is locked by the connection of the clutch 105, and the driving force transmitted to the pair of side gears 117, 119 is evenly output to the left and right wheels. Thus, the drive unit 101, which has a clutch 105 that enables the differential clutch of the differential mechanism 103, has a differential locking function.

[0072] The clutch part 105 is located between the side gear 119 and the clutch component 131.

[0073] The clutch component 131 is formed in an annular shape, and its base, formed by a single component connected circumferentially, is axially movable between the wall of the differential housing 111 and the back side of the side gear 119. An engagement portion 133 is provided on the wall side of the differential housing 111 of the clutch component 131, capable of rotatably engaging with the differential housing 111, and a clutch portion 105 is provided on the back side of the side gear 119 of the clutch component 131.

[0074] The engaging portion 133 consists of a plurality of protrusions evenly spaced circumferentially at the base of the clutch component 131, and a plurality of holes evenly spaced circumferentially at the wall of the differential housing 111 extending axially. By engaging the protrusions and holes in the rotational direction, the clutch component 131 is prevented from rotating by the differential housing 111, allowing the clutch component 131 and the differential housing 111 to rotate as a unit.

[0075] The engaging portion 133 is provided with a cam that moves the clutch component 131 along the connection direction of the clutch portion 105. The cam is a cam surface with the same inclination angle formed on opposing surfaces on both sides of the protrusion and the bore. When the clutch component 131 moves along the connection direction of the clutch portion 105 and a rotational engagement occurs in the clutch portion 105, the cam surfaces engage due to the rotation of the differential housing 111. Due to the engagement of the cam surfaces, the clutch component 131 moves further along the engagement direction of the clutch portion 105, and the connection of the clutch portion 105 is strengthened.

[0076] The clutch portion 105 is provided axially between the clutch component 131 and the back side of the side gear 119, and multiple clutch portions are meshing teeth formed circumferentially on the clutch component 131 and the side gear 119 respectively and meshing with each other. In the clutch portion 105, the clutch component 131 and the side gear 119 can be integrally connected by the meshing of their meshing teeth, that is, the differential housing 111 and the side gear 119 can be integrally rotatably connected, and the differential mechanism 103 is locked.

[0077] On the other hand, a force-applying member 135 is provided axially between the clutch component 131 and the back side of the side gear 119, and radially inside the clutch portion 105, and a force is always applied to the clutch component 131 in the disengagement direction of the clutch portion 105. Through the force-applying member 135, the clutch component 131 moves in the disengagement direction of the clutch portion 105, the engagement of the clutch portion 105 is released, and the differential of the differential mechanism 103 becomes unlocked. The engagement / disengagement state of the clutch portion 105 is controlled by the drive 107.

[0078] The driver 107 includes a conversion mechanism 137 and an electric motor 141 as an electrical component 139.

[0079] The conversion mechanism 137 is a cam mechanism that converts the rotational force of the electric motor 141 into an axial operating force. The conversion mechanism 137 includes a cam ring 143.

[0080] The cam ring 143 is formed in an annular shape, and its outer surface is an axially inclined cam surface. The cam ring 143 has multiple pressing portions that abut against the axial end face of the protrusion of the clutch component 131. The cam surface of the cam ring 143 engages with the rotor 151 of the electric motor 141, and moves in the connection direction of the clutch portion 105 due to the rotation of the rotor 151. The movement of the cam ring 143 presses the clutch component 131 via the pressing portions, causing the clutch component 131 to move in the connection direction of the clutch portion 105 against the force applied by the force-applying member 135, thereby engaging the clutch portion 105. Furthermore, rollers or similar components that promote the axial movement of the cam ring 143 can be provided between the cam ring 143 and the cam surface of the rotor 151.

[0081] An electric motor 141 is housed within a motor housing 145 located on the outer periphery of a protrusion 123 in a differential housing 111. The motor housing 145 has an axially opening clutch component 131, and an integrally formed engagement portion 147 on its outer periphery engages with the housing, thereby preventing rotation by the housing. The electric motor 141 includes a stator 149 and a rotor 151.

[0082] The stator 149 is formed in a ring shape and includes a magnetic core and an electromagnetic coil. The magnetic core is made of magnetic material, and multiple magnetic cores are arranged circumferentially and fixed to the motor housing 145. The electromagnetic coil is wound around the outer periphery of the multiple magnetic cores a predetermined number of times and generates an axial magnetic flux by energizing them. Leads 153 extending to the outside of the motor housing 145 are electrically connected to the ends of the electromagnetic coils. The leads 153 extending from the motor housing 145 are led to the outside of the housing and electrically connected to a controller (not shown) that controls the operation of various mechanisms mounted on the vehicle.

[0083] The rotor 151 is made of magnetic material and formed in a ring shape. The rotor 151 is rotatably disposed inside the motor housing 145. The rotor 151 is axially opposed to the stator 149 through a small gap allowing magnetic flux to pass through. Furthermore, to increase the magnetic flux transmission area, multiple protrusions are formed on the axially opposed surfaces of the rotor 151 and stator 149 in a radially staggered arrangement. The rotor 151 rotates using magnetic flux generated by energizing the electromagnetic coils of the stator 149.

[0084] When the clutch 105 is engaged, the drive 107 energizes the electromagnetic coil of the stator 149 to rotate the rotor 151. The rotation of the rotor 151 causes the conversion mechanism 137 to move the cam ring 143 toward the engagement direction of the clutch 105. This movement of the cam ring 143 presses the clutch component 131 via the pressing part, causing the clutch component 131 to move toward the engagement direction of the clutch 105 against the force applied by the force-applying member 135, thus engaging the clutch 105. The engagement of the clutch 105 allows the differential box 111 and the side gear 119 to rotate as a unit, and the differential mechanism 103 is locked.

[0085] On the other hand, when the drive 107 disengages the clutch 105, it stops energizing the electromagnetic coil of the stator 149. Since energizing the electromagnetic coil stops, the clutch component 131 moves in the disengagement direction of the clutch 105 via the force application component 135, thus disengaging the clutch 105. Disengaging the clutch 105 allows the differential housing 111 and the side gear 119 to rotate relative to each other, and the differential mechanism 103 becomes unlocked.

[0086] Temperature sensor 109 is disposed inside the housing in the stator 149 of electric motor 141, which is an electrical component 139. Alternatively, temperature sensor 109 can be disposed on the stator 149 side; for example, it can be disposed on the motor housing 145 where the stator 149 is fixed. By disposing of temperature sensor 109 on the stator 149 side, it can be treated as a component of driver 107, improving assemblability. Furthermore, temperature sensor 109 can be disposed, for example, near the lead-out portion of the lead wire 153 extending from the motor housing 145 to the outer housing. The lead wire (not shown) extending to the outer housing is electrically connected to temperature sensor 109. The lead wire is electrically connected to the controller.

[0087] Temperature sensor 109 detects the internal temperature of the housing and outputs it to the controller. The controller estimates the temperature of clutch 105 based on the temperature detected by temperature sensor 109, and controls the energization of the electromagnetic coil according to the temperature of clutch 105. In estimating the temperature of clutch 105 by the controller, the estimation accuracy can be significantly improved compared to the case where temperature sensor 109 is arranged inside the housing.

[0088] The leads of the temperature sensor 109 converge with the leads 153 of the electromagnetic coil and are led out from the lead-out portion provided in the housing to the outside of the housing. Therefore, there is no need to rearrange the structure of the housing to lead out the temperature sensor 109, and the structure of the housing is not complicated. In addition, by providing the temperature sensor 109 on the electrical component 139 disposed inside the housing, there is no need to consider the lubrication environment of the lubricating oil as when the temperature sensor 109 is repositioned in the lubricating oil reservoir.

[0089] The temperature sensor 109 is disposed below the oil level L of the lubricating oil inside the housing. By disposing the temperature sensor 109 below the oil level L, the temperature sensor 109 is disposed within the lubricating oil. Therefore, the temperature sensor 109 can more accurately detect the temperature of the lubricating oil, and the estimation accuracy of the temperature of the clutch 105 can be further improved.

[0090] Temperature sensor 109 is disposed on the outside of motor housing 145, for example, exposed inside the housing on the stator 149 side. Temperature sensor 109 exposed inside the housing is an oil-resistant temperature sensor that can come into contact with lubricating oil. Because temperature sensor 109 is in contact with lubricating oil, the temperature of the lubricating oil can be detected more accurately, and the estimation accuracy of the temperature of clutch 105 can be further improved.

[0091] Here, the temperature sensor 109 can also be disposed inside the stator 149 or the motor housing 145 on the stator 149 side, for example, without being exposed inside the housing. The temperature sensor 109, not exposed inside the housing, cannot come into contact with lubricating oil. Therefore, the temperature sensor 109 does not need to be oil-resistant, which reduces its cost. Furthermore, since the temperature sensor 109 is disposed inside the stator 149 side, it will not interfere with surrounding components, improving its durability.

[0092] The drive unit 101 includes a housing for containing lubricating oil, and a differential housing 111 and a side gear 119, which are rotatably housed within the housing as a pair of rotating components. It also includes a clutch unit 105 for engaging and disengaging power transmitted between the differential housing 111 and the side gear 119, and a driver 107 housed within the housing and equipped with an electrical component 139 for actuating the clutch unit 105. Furthermore, the electrical component 139 is equipped with a temperature sensor 109 for detecting the temperature inside the housing.

[0093] Since the temperature sensor 109 is housed within the electrical component 139, which is housed in the housing, it is positioned inside the housing. Therefore, compared to positioning the temperature sensor 109 on the outer surface of the housing, the accuracy of temperature estimation for the clutch portion 105 can be significantly improved. Furthermore, by positioning the temperature sensor 109 within the electrical component 139, the leads of the temperature sensor 109 and the leads 153 of the electrical component 139 can be converged and led out from the housing to the outside. Therefore, there is no need to restructure the housing to route the leads of the temperature sensor 109, thus avoiding structural complexity. In addition, by positioning the temperature sensor 109 within the electrical component 139, which is located inside the housing, the lubrication environment of the lubricating oil does not need to be considered as if the temperature sensor 109 were repositioned within the lubricating oil reservoir.

[0094] Therefore, in such a drive device 101, the structure of the housing is not complicated, and the estimated accuracy of the temperature of the clutch 105 can be maintained.

[0095] Additionally, the electrical component 139 comprises an electric motor 141, which has a stator 149 fixed to the housing and a rotor 151 that rotates by energizing the stator 149. Furthermore, a temperature sensor 109 is located on the stator 149 side.

[0096] By placing the temperature sensor 109 on the stator 149 side, the temperature sensor 109 can be treated as a component of the driver 107, which improves assemblability.

[0097] In addition, the temperature sensor 109 is positioned below the oil level L of the lubricating oil.

[0098] Therefore, by arranging a temperature sensor 109 in the lubricating oil, the temperature sensor 109 can accurately detect the temperature of the lubricating oil and further improve the estimation accuracy of the temperature of the clutch 105.

[0099] In addition, the temperature sensor 109 can be configured to contact the lubricating oil.

[0100] Therefore, since the temperature sensor 109 is in contact with the lubricating oil, the temperature of the lubricating oil can be detected more accurately, and the estimation accuracy of the temperature of the clutch 105 can be further improved.

[0101] In addition, the temperature sensor 109 is disposed inside the stator 149 side so that it cannot come into contact with the lubricating oil.

[0102] Therefore, the temperature sensor 109 does not need to be oil-resistant, which reduces the cost of the temperature sensor 109. In addition, since the temperature sensor 109 is disposed inside the stator 149, the temperature sensor 109 will not interfere with surrounding components, which improves the durability of the temperature sensor 109.

[0103] Although this embodiment has been described above, it is not limited thereto, and various modifications can be made within the scope of the spirit of this embodiment.

[0104] For example, although the electrical component here is an electric motor, it is not limited to this; the electrical component can be any type of component, such as an electromagnet.

[0105] In addition, the pair of rotating parts is not limited to the above. For example, the housing and inner housing of a free-running differential can be used as a pair of rotating parts, and the pair of rotating parts can be of any type.

Claims

1. A driving device, characterized in that, have: The outer casing, which contains the lubricating oil; A pair of rotating components, which are rotatably housed in the housing; A clutch that engages or disengages the power transmitted between the pair of rotating components; as well as A drive, housed in the housing, has an electrical component that actuates the clutch, and the electrical component is provided with a temperature sensor that detects the temperature inside the housing.

2. The driving device according to claim 1, characterized in that, The electrical component comprises an electric motor having a stator fixed to the housing and a rotor that rotates by energizing the stator. The temperature sensor is located on the stator side.

3. The driving device according to claim 1 or 2, characterized in that, The temperature sensor is positioned below the surface of the lubricating oil.

4. The driving device according to claim 1 or 2, characterized in that, The temperature sensor is configured to come into contact with the lubricating oil.

5. The driving device according to claim 2, characterized in that, The temperature sensor is disposed inside the stator side in a manner that prevents it from contacting the lubricating oil.

Images