JP2013154827A - Driving force transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving force transmission device can reducing cost by reducing power consumption during switching of a driving state and during front/rear torque distribution in a four-wheel driving state.SOLUTION: A driving force transmission device 1 includes: a housing 12 and an inner shaft 13 which are disposed in a second driving force intermitting part 4 and are mutually and relatively rotatable; and a pump device including a pump 50 for synchronization which is operated by relative rotation of the housing 12 and the inner shaft 13, and a pump 33 for torque distribution which is operated by relative rotation of a propeller shaft 2 and a vehicle body side. In the pump device, the pump 50 for synchronization and the pump 33 for torque distribution impart discharge pressure for operating a multiple plate clutch 8 interposed between the housing 12 and the inner shaft 13 to a piston 9.

Description

  The present invention relates to a driving force transmission device in a four-wheel drive vehicle.

  Some conventional driving force transmission devices are mounted on a four-wheel drive vehicle that can be switched from a four-wheel drive state to a two-wheel drive state and from a two-wheel drive state to a four-wheel drive state (see, for example, Patent Document 1). ).

  This type of driving force transmission device includes a first driving force interrupting portion that connects the driving source side and the propeller shaft in an intermittent manner, and a second driving that connects the propeller shaft and the rear wheel side axle shaft in an intermittent manner. And a power interrupter.

  The first driving force interrupting portion is disposed between the front differential and the propeller shaft, and is entirely constituted by a dog clutch. In the front differential, the front differential case is connected to the drive source side, and the side gear is connected to each front wheel side axle shaft. The propeller shaft is connected to the differential case of the rear differential via a first driving force interrupting portion.

  The second driving force interrupting portion includes a first rotating member and a second rotating member, and is disposed between the rear differential and one rear wheel side axle shaft. In the rear differential, one side gear is connected to one rear wheel axle shaft through a second driving force interrupting portion, and the other side gear is connected to the other rear wheel axle shaft.

  In the driving force transmission device configured as described above, the front differential and the propeller shaft are connected via the first driving force interrupting portion during four-wheel drive. Further, the propeller shaft and the one rear wheel side axle shaft are connected to each other via the rear differential and the second driving force intermittent portion, and the propeller shaft and the other rear wheel side axle shaft are connected to each other via the rear differential. On the other hand, during two-wheel drive, the connection between the front differential and the propeller shaft is released, and the connection between the propeller shaft and one rear wheel axle shaft is released.

JP2011-79421A

  However, according to the driving force transmission device disclosed in Patent Document 1, since the electric pump is used as the driving source of the second driving force interrupting unit, when switching between the two-wheel driving state and the four-wheel driving state (in the driving state) There is a problem that power is consumed and the cost is increased when switching the front and rear torque in the four-wheel drive state during switching.

  Accordingly, an object of the present invention is to provide a driving force transmission device that can reduce power consumption at the time of switching the driving state and at the time of front-rear torque distribution in the four-wheel driving state, thereby reducing the cost. There is.

  In order to achieve the above object, the present invention provides the driving force transmission devices (1) to (5).

(1) To achieve the above object, the present invention receives a driving force of a driving source in a four-wheel drive vehicle and transmits it from the main driving wheel side to the auxiliary driving wheel side, and the driving force transmission A shaft and the drive source side are connected in an intermittent manner, and are arranged on the auxiliary driving wheel side of the first driving force interrupting portion, the first driving force interrupting portion arranged on the main driving wheel side, A second driving force interrupting portion that connects the driving force transmission shaft and the auxiliary driving wheel side; and at least one of the second driving force interrupting portion and the first driving force interrupting portion. A pair of rotating members that are rotatable relative to each other, a first pump that operates by relative rotation of the pair of rotating members, and a second that operates by relative rotation of the driving force transmission shaft and the vehicle body side. A pump device having a pump, wherein the pump device is the first device. Driving force transmission device for imparting to the piston a discharge pressure of the pump and the second pump actuates the clutch interposed between the pair of rotary members.

(2) In the driving force transmission device according to (1) above, in the pump device, the flow rate of hydraulic oil corresponding to the discharge pressure is controlled by a flow control valve.

(3) In the driving force transmission device according to (1), the pair of rotating members are connected to one rotating member on the driving force transmitting shaft side and the other rotating member to the auxiliary driving wheel side. The driving force transmission device according to claim 1.

(4) In the driving force transmission device according to (3), the pair of rotating members may be a pair of auxiliary driving wheels on the auxiliary driving wheel side between the one rotating member and the driving force transmission shaft. A differential that distributes the driving force is interposed.

(5) In the driving force transmission device according to (1) or (2), the pump device includes the first pump between the pair of rotating members, and the second pump serving as the driving force transmission shaft. Between the vehicle body and the vehicle body.

  According to the present invention, it is possible to reduce the power consumption when switching the driving state and when distributing the front-rear torque in the four-wheel driving state, and it is possible to reduce the cost.

The top view shown in order to demonstrate the outline of the vehicle by which the driving force transmission apparatus which concerns on embodiment of this invention is mounted. Sectional drawing shown in order to demonstrate the 2nd driving force interruption part in the driving force transmission apparatus which concerns on embodiment of this invention. The hydraulic circuit diagram shown in order to demonstrate the pump apparatus of the driving force transmission apparatus which concerns on embodiment of this invention.

[Embodiment]
FIG. 1 schematically shows a four-wheel drive vehicle. As shown in FIG. 1, a four-wheel drive vehicle 101 includes a driving force transmission device 1, an engine 102, a transmission 103, a pair of front wheels 104L and 104R as main drive wheels, and a pair of rear wheels 105L and 105R as auxiliary drive wheels. It has.

  The driving force transmission device 1 is disposed along with a front differential 106 and a rear differential 107 on a driving force transmission path from the transmission 103 side to the rear wheel side in the four-wheel drive vehicle 101, and a vehicle body (not shown) of the four-wheel drive vehicle 101. ).

  The driving force transmission device 1 includes a propeller shaft (driving force transmission shaft) 2, a first driving force interrupting portion 3, and a second driving force interrupting portion 4, and the four-wheel drive vehicle 101 is in a four-wheel drive state. Can be switched to a two-wheel drive state, and the two-wheel drive state can be switched to a four-wheel drive state. Details of the driving force transmission device 1 will be described later.

  The front differential 106 can rotate a pair of side gears 109L and 109R connected to the front wheel axle shafts 108L and 108R, a pair of pinion gears 110 that mesh with the pair of side gears 109L and 109R at right angles to each other, and a pair of pinion gears 110. And a pair of pinion gears 110, a gear support member 130, and a front differential case 111 that houses a pair of side gears 109 L and 109 R, between the transmission 103 and the first driving force interrupting portion 3. Has been placed.

  The rear differential 107 rotates a pair of side gears 113L and 113R connected to the rear wheel axle shafts 112L and 112R, a pair of pinion gears 114 meshed with the pair of side gears 113L and 113R at right angles to each other, and a pair of pinion gears 114. A gear support member 115 and a rear differential case 116 that accommodates the gear support member 115, the pair of pinion gears 114, and the pair of side gears 113L and 113R are provided to support the propeller shaft 2 and the rear axle shafts 112L and 112R. Arranged between. The rear differential case 116 is rotatably supported in a differential carrier 40 (described later) via tapered roller bearings 117 and 118.

  The engine 102 drives the pair of front wheels 104L and 104R by outputting a driving force to the pair of front wheel axle shafts 108L and 108R via the transmission 103 and the front differential 106.

  The engine 102 outputs the driving force to the rear wheel side axle shaft 112R via the transmission 103, the first driving force interrupting section 3, the propeller shaft 2 and the rear differential 107, so that the rear wheel 105R is transmitted to the rear wheel 105R. , The driving force is output to the rear wheel side axle shaft 112L via the first driving force interrupting portion 3, the propeller shaft 2, the rear differential 107 and the second driving force interrupting portion 4, thereby causing the other rear wheel 105L to be output respectively. To drive.

[Overall configuration of the driving force transmission device 1]
FIG. 2 shows a driving force transmission device. FIG. 3 shows a hydraulic circuit. As shown in FIGS. 1 and 2, the driving force transmission device 1 includes a propeller shaft 2, a first driving force interrupting unit 3, and a second driving force interrupting unit 4, and an ECU (Electronic Control) for a vehicle as a control unit. Unit) 5 is added to the general configuration.

(Configuration of propeller shaft 2)
The propeller shaft 2 includes a plurality of shaft portions 20 (only the lower shaft portion is illustrated) and a connecting portion 21, and is disposed between the first driving force interrupting portion 3 and the second driving force interrupting portion 4. Yes. The propeller shaft 2 is configured to receive the driving force of the engine 102 from the front differential case 111 and transmit it from the front wheels 104L, 104R side to the rear wheels 105L, 105R side. A front wheel side gear mechanism 6 including a drive pinion 60 and a ring gear 61 that mesh with each other is disposed at the front wheel side end of the propeller shaft 2. A gear mechanism 7 including a drive pinion 70 and a ring gear 71 that mesh with each other is disposed at the rear wheel side end of the propeller shaft 2.

  The shaft portion 20 is rotatably supported in the differential carrier 40 via tapered roller bearings 30 and 31.

  The connecting portion 21 is attached to the outer peripheral surface of the shaft portion 20 through the shaft portion 20, and is entirely formed of a bottomless cylindrical member with a hook. A cover member 32 that closes the upper opening of the differential carrier 40 is attached to the outer peripheral surface of the connecting portion 21. Further, a torque distribution pump (second pump) 33 interposed between the outer peripheral surface of the connecting portion 21 and the inner peripheral surface of the differential carrier 40 is disposed.

  The torque distribution pump 33 is composed of, for example, a trochoid pump having two inner and outer gears 330 and 331 and a pair of side plates 332 and 333, and is connected to a torque distribution hydraulic circuit A. The torque distribution pump 33 is operated by relative rotation of the gears 330 and 331 (rotation of the gear 330 in the present embodiment), and applies a discharge pressure for operating the multi-plate clutch 8 to the piston 9. It is configured.

  One gear 330 is attached to the outer peripheral surface of the coupling portion 21 in the propeller shaft 2 and is entirely formed of an external gear having a trochoidal tooth shape.

  The other gear 331 is arranged on the outer periphery of one gear 330 with its center axis decentered relative to its center axis, and is attached to the inner peripheral surface of the differential carrier 40, and the entire gear 331 meshes with one gear 330. It is formed by a tooth-shaped internal gear.

  The pair of side plates 332 and 333 oppose each other via one gear 330 and the other gear 331, and are disposed between the outer peripheral surface of the coupling portion 21 and the inner peripheral surface of the differential carrier 40 in the propeller shaft 2. . The pair of side plates 332 and 333 are configured to seal a pump space (not shown) formed between one gear 330 and the other gear 331. One (lower) side plate 332 is provided with a suction port 332a, and the other side plate 333 is provided with a discharge port 333a that communicates with the pump space. Movement of the other side plate 333 on the opposite side to the one side plate 332 is restricted by a retaining ring 119.

  As shown in FIG. 3, in the torque distribution hydraulic circuit A, a plurality of circuit components connected to a concave hole 180 a (described later) functioning as a cylinder are arranged together with a torque distribution pump 33. The circuit parts include, for example, a tank 34 that stores hydraulic oil, a check valve 35 that prevents the hydraulic oil from flowing from the tank 34 side to the discharge side of the torque distribution pump 33, and a hydraulic circuit A for torque distribution. And a flow rate control valve 37 for controlling the flow rate of the hydraulic fluid corresponding to the discharge pressure of the torque distribution pump 33. In the torque distribution hydraulic circuit A, the check valve 35 is near the discharge side of the torque distribution pump 33, the relief valve 36 is downstream of the check valve 35, and the flow control valve 37 is downstream of the relief valve 36. Each is arranged. The torque distribution hydraulic circuit A is configured to supply hydraulic oil to the concave hole 180a by the operation of the torque distribution pump 33 by the relative rotation of the propeller shaft 2 and the differential carrier 40.

(Configuration of the first driving force interrupting section 3)
As shown in FIG. 1, the first driving force interrupting section 3 is formed of, for example, a dog clutch, is disposed on the front wheels 104 </ b> L and 104 </ b> R side of the four-wheel drive vehicle 101, and is connected to the ECU 5 via the actuator 55. And the 1st driving force interruption part 3 is comprised so that the propeller shaft 2 and the front differential case 111 may be connected intermittently.

(Configuration of the second driving force interrupting section 4)
As shown in FIG. 2, the second driving force interrupting portion 4 has a multi-plate clutch 8, is disposed on the rear wheels 105 </ b> L and 105 </ b> R side of the four-wheel drive vehicle 101, and is accommodated in the differential carrier 40. Yes.

  The second driving force interrupting section 4 is configured to connect the propeller shaft 2 (shown in FIG. 1) and the rear wheel side axle shaft 112L (shown in FIG. 1) in an intermittent manner. That is, the rear wheel side axle shaft 112L and the propeller shaft 2 are connected with the second driving force interrupting portion 4 interposed therebetween. The rear wheel side axle shaft 112R and the propeller shaft 2 are connected without the second driving force interrupting portion 4 interposed.

  As a result, at the time of connection by the second driving force interrupting portion 4, the rear wheel side axle shaft 112 </ b> L and the propeller shaft 2, and the rear wheel side axle shaft 112 </ b> R and the propeller shaft 2 are both connected via the gear mechanism 7 and the rear differential 107. Connected to transmit torque. On the other hand, when the connection by the second driving force transmission unit 4 is released, the connection between the rear wheel side axle shaft 112L and the propeller shaft 2 is cut off, but the rear wheel side axle shaft 112R and the propeller shaft 2 are connected to each other by a gear mechanism. 7 and the rear differential 107 remain connected.

  The differential carrier 40 includes first to third carrier elements 400 to 402 that house the components of the driving force transmission device 1 and is mounted on the vehicle body of a four-wheel drive vehicle 101 (shown in FIG. 1).

  The first carrier element 400 opens forward and to the left of the four-wheel drive vehicle 101 and is disposed on one axial side of the differential carrier 40 (right in FIG. 2). The first carrier element 400 is configured to accommodate a part of the propeller shaft 2 and the rear differential 107 therein. The first carrier element 400 is provided with a shaft insertion hole 400a through which the rear wheel side axle shaft 112R is inserted. A seal mechanism 38 interposed between the outer peripheral surface of the rear wheel axle shaft 112R is disposed on the inner peripheral surface of the shaft insertion hole 400a. In addition, a seal mechanism 39 interposed between the outer peripheral surface of the connecting portion 21 of the propeller shaft 2 is disposed on the inner peripheral surface of the upper opening portion of the first carrier element 400.

  The second carrier element 401 closes one side opening of the third carrier element 402 and is arranged on the other side in the axial direction of the differential carrier 40 (left side in FIG. 2). The second carrier element 401 is provided with a shaft insertion hole 401a through which the rear wheel side axle shaft 112L is inserted. On the inner peripheral surface of the second carrier element 401, a seal mechanism 41 interposed between the outer peripheral surface of the rear wheel axle shaft 112L is disposed.

  The third carrier element 402 is disposed between the first carrier element 400 and the second carrier element 401 and is disposed at the intermediate portion in the axial direction of the differential carrier 40. The third carrier element 402 is configured to accommodate a part of the multi-plate clutch 8, the housing 12 and the inner shaft 13. On the inner peripheral surface of the third carrier element 402, a seal mechanism 42 interposed between the outer peripheral surface of the housing 12 (front housing 18) is disposed.

  The multi-plate clutch 8 comprises a friction type main clutch having a plurality of inner clutch plates 80 and a plurality of outer clutch plates 81, and is formed between the housing 12 as one rotating member and the inner shaft 13 as the other rotating member. Is arranged. The multi-plate clutch 8 frictionally engages the inner and outer clutch plates adjacent to each other out of the inner clutch plate 80 and the outer clutch plate 81, and also releases the frictional engagement to connect the housing 12 and the inner shaft 13 together. It is configured to be connected so as to be intermittent (torque transmission).

  The inner clutch plates 80 and the outer clutch plates 81 are alternately arranged along the rotation axis O, and are entirely formed by an annular friction plate.

  The inner clutch plate 80 has a straight spline fitting portion 80a on its inner periphery, and the straight spline fitting portion 80a is fitted to the straight spline fitting portion 130a of the cylindrical portion 13a (inner shaft 13) to form an inner shaft. 13 is connected so as not to be relatively rotatable and relatively movable.

  The inner clutch plate at the end of the rear differential side among the plurality of inner clutch plates 80 functions as an input portion of the multi-plate clutch 8 and is pressed from the piston 9 (described later) to the outer clutch plate 81 side via the pressing member 17. When the force P is received, the multi-plate clutch 8 side (the direction in which the inner clutch plate 80 and the outer clutch plate 81 are frictionally engaged with each other) is moved by the movement in the pressing direction.

  The outer clutch plate 81 has a straight spline fitting portion 81 a on the outer peripheral portion thereof, and the straight spline fitting portion 81 a is fitted to a straight spline fitting portion 190 a (described later) of the rear housing 19 to rotate relative to the housing 12. It is impossible and relative movement is connected.

  The housing 12 includes a front housing 18 and a rear housing 19 and is rotatably supported in the differential carrier 40 via a ball bearing 43 on the axis (rotational axis O) of the rear wheel axle shaft 112L (shown in FIG. 1). And connected to the side gear 113L by spline fitting.

  The front housing 18 has body portions 18a to 18c having different outer diameters, and is disposed on one side in the axial direction of the housing 12 (right side in FIG. 2), and the whole is open to the rear housing 19 side. It is formed by a bottom cylindrical member. Further, the front housing 18 is connected to the rear housing 19 so as not to be relatively rotatable by spline fitting, and the movement of the front housing 18 is restricted by retaining rings 44 and 45 in the axial direction of the rear housing 19. The outer diameter of the trunk portion 18a is the largest dimension (maximum outer diameter), the outer diameter of the trunk portion 18b is the smallest dimension (minimum outer diameter), and the outer diameter of the trunk portion 18c is the outer diameter of the trunk portion 18a. The dimension (intermediate outer diameter) is set between the outer diameter of the portion 18b.

  The body portion 18 a has a recessed hole 180 a that is sealed by the piston 9, and is disposed on the rear housing 19 side of the front housing 18.

  The body portion 18b is disposed on the side of the rear differential 107 of the front housing 18, and is connected to the side gear 113L by spline fitting, and is entirely formed by a stepped round shaft member.

  The body portion 18c has an oil passage 180c and a recessed hole 181c, and is disposed between the body portion 18a and the body portion 18b at an intermediate portion in the axial direction of the front housing 18.

  The oil passage 180c communicates with the concave hole 180a of the body portion 18a and is connected to the hydraulic circuit A for torque distribution and the hydraulic circuit B for synchronization.

  The concave hole 181c is formed by a cylindrical space that opens to the multi-plate clutch 8 side. An annular convex portion 182c that protrudes toward the multi-plate clutch 8 is provided on the opening periphery of the concave hole 181c. On the outer periphery of the convex portion 182c, a spring receiving member 46 is disposed on the multi-plate clutch 8 side, and a piston 9 is disposed on the rear differential 107 side.

  The spring receiving member 46 has a flange 46a on the outer peripheral surface, is attached to the outer peripheral surface of the convex portion 182c by a retaining ring 47, and is entirely formed of a cylindrical member through which the convex portion 182c is inserted.

  The piston 9 has a cylindrical pressure applying portion 9a that applies the discharge pressure of the torque distributing pump 33 and the synchronizing pump 50 to the pressing member 17, and is located between the spring receiving member 44 and the bottom surface of the concave hole 180a. The whole is formed by the annular member which inserts the convex part 182c. An annular seal member 48 that can slide on the inner peripheral surface of the concave hole 180a is provided on the outer peripheral edge of the piston 9, and an annular seal that can slide on the outer peripheral surface of the convex portion 182c on the inner peripheral edge of the piston 9. Each member 49 is attached. The piston 9 causes the inner peripheral surface of the concave hole 180a and the outer peripheral surface of the convex portion 182c to move in the direction of the rotation axis O by supplying hydraulic oil to the concave hole 180a by the operation of the torque distribution pump 33 or the synchro pump 50. It is configured to slide. The flow rate of the hydraulic oil supplied to the concave hole 180a corresponds to the discharge pressure of the torque distribution pump 33 or the synchro pump 50, and is controlled by the flow control valve based on the set pressure. On the multi-plate clutch 8 side of the piston 9, a plurality of return springs 100 that are interposed between the flange 46 a of the spring receiving member 46 and are arranged in parallel at equal intervals around the outer periphery of the convex portion 182 c of the front housing 18 are arranged. Has been.

  The synchro pump 50 is composed of, for example, a trochoid pump having two internal and external gears 500 and 501 and a pair of side plates 502 and 503 (the side plate 502 is the front housing 18), and is disposed in the concave hole 181c and is a hydraulic pressure for synchro. Connected to circuit B. The sync pump 50 is configured to operate by the relative rotation of the gears 500 and 501, and apply a discharge pressure for operating the multi-plate clutch 8 to the piston 9. The synchronizing pump 50 constitutes the pump device of the present invention together with the torque distribution pump 33.

  One gear 500 is attached to the outer peripheral surface of the inner shaft 13 (shaft portion 13d), and is entirely formed of an external gear having a trochoidal tooth shape.

  The other gear 501 is arranged on the outer periphery of one gear 500 with its center axis decentered relative to its center axis, and is attached to the inner peripheral surface of the body portion 18c, and the entire gear 501 meshes with the one gear 500 as a whole. It is formed by a tooth-shaped internal gear.

  The pair of side plates 502 and 503 face each other via one gear 500 and the other gear 501 and are disposed between the outer peripheral surface of the inner shaft 13 and the inner peripheral surface of the recessed hole 180c. The pair of side plates 502 and 503 are configured to seal a pump space (not shown) formed between one gear 500 and the other gear 501. One side plate 502, that is, the front housing 18 (body portion 18c) is provided with a suction port 502a and a discharge port 502b in communication with the pump space. The other side plate 503 is restricted by the retaining ring 120 from moving to the opposite side of the one side plate 502.

  As shown in FIG. 3, in the synchronizing hydraulic circuit B, a plurality of circuit components connected to the recessed hole 180 a functioning as a cylinder are arranged together with the synchronizing pump 50. The circuit parts include, for example, a tank 34 that stores hydraulic oil, a check valve 51 that blocks the flow of hydraulic oil from the tank 34 side to the discharge side of the sync pump 50, and a surplus hydraulic circuit B for sync. A relief valve 36 for returning the working oil to the tank 34 and a flow rate control valve 37 for controlling the flow rate of the working oil corresponding to the discharge pressure of the synchro pump 50. The synchronizing hydraulic circuit B is configured to supply hydraulic oil to the concave hole 180 a by the operation of the synchronizing pump 50 by the relative rotation of the front housing 18 and the inner shaft 13.

  As shown in FIG. 2, the rear housing 19 is disposed on the other side in the axial direction of the housing 12 (left side in FIG. 2), and is accommodated in the differential carrier 40, and the bottom is open to the front housing 18 as a whole. It is formed by a cylindrical member. The rear housing 19 is configured to rotate around the rotation axis O together with the front housing 18. The rear housing 19 is provided with three holes 19a to 19c having different inner diameters. The inner diameter of the hole 19a is the largest dimension (maximum inner diameter), the inner diameter of the hole 19b is the smallest dimension (minimum inner diameter), and the inner diameter of the hole 19c is the inner diameter of the hole 19a and the inner diameter of the hole 19b. The dimension between them (intermediate inner diameter) is set.

  The hole 19a is adjacent to the concave hole 180a via the piston 9, and is disposed on one axial side of the rear housing 19 (right side in FIG. 2). A straight spline fitting portion 190a that is spline fitted to the straight spline fitting portion 81a of the outer clutch plate 81 and the straight spline fitting portion 17a of the pressing member 17 is provided on the inner peripheral surface of the hole 19a.

  The hole 19b is inserted through the inner shaft 13 and is disposed on the other axial side of the rear housing 19 (left side in FIG. 2).

  The hole portion 19 c communicates with both the hole portions 19 a and 19 b and is disposed at an intermediate portion in the axial direction of the rear housing 19.

  The inner shaft 13 has three cylindrical portions 13 a to 13 c having different outer diameters, and a shaft portion 13 d that is continuous with the cylindrical portions 13 a to 13 c, and is disposed on the rotation axis O of the housing 12. The ball bearing 52 and the needle roller bearing 53 are rotatably supported, and the whole is formed by a bottomless cylindrical member that opens on both sides in the axial direction. In the cylindrical portions 13a to 13c, the outer diameter of the cylindrical portion 13a is the maximum dimension (maximum outer diameter), the outer diameter of the cylindrical portion 13b is the minimum dimension (minimum outer diameter), and the outer diameter of the cylindrical portion 13c is cylindrical. The dimension (intermediate outer diameter) is set between the outer diameter of the portion 13a and the outer diameter of the cylindrical portion 13b. The outer diameter of the shaft portion 13d is set to be smaller than the outer diameter of the cylindrical portions 13a to 13c. And the inner shaft 13 is comprised so that the front-end | tip part of the rear-wheel side axle shaft 112L (shown in FIG. 1) may be inserted and accommodated in the opening part. The rear-wheel-side axle shaft 112L is secured to the inner shaft 13 by a retaining ring 54 and is connected to the inner shaft 13 so as not to be relatively rotatable by spline fitting.

  The cylindrical portion 13a having the maximum outer diameter is disposed between the cylindrical portion 13b having the minimum outer diameter and the cylindrical portion 13c having the intermediate outer diameter. A straight spline fitting portion 130 a corresponding to the straight spline fitting portion 80 a of the inner clutch plate 80 is provided on the outer peripheral surface of the cylindrical portion 13 a having the maximum outer diameter.

  The cylindrical portion 13b having the smallest outer diameter has an outer circumferential surface facing the inner circumferential surface of the convex portion 182c via the needle roller bearing 53, and is interposed between the cylindrical portion 13a having the largest outer diameter and the shaft portion 13d. Are arranged.

  The intermediate outer diameter cylindrical portion 13c has an outer peripheral surface facing the inner peripheral surface of the hole portion 19c via a ball bearing 52, and is disposed on the other axial side of the inner shaft 13 (left side in FIG. 2). Yes.

  The shaft portion 13d is disposed on one side in the axial direction of the inner shaft 13 (right side in FIG. 2), and is accommodated in the concave hole 181c. A synchro pump 50 is disposed on the outer periphery of the shaft portion 13d.

(Configuration of ECU 5)
As shown in FIG. 1, the ECU 5 is mounted on the vehicle body of the four-wheel drive vehicle 101 and is connected to the actuator 55 of the first driving force interrupting portion 3 and the actuator 56 of the second driving force interrupting portion 4. . The ECU 5 is connected to a rotation sensor 15 that detects the rotation speed of the front differential case 111 and a rotation sensor 16 that detects the rotation speed of the propeller shaft 2.

The actuator 55 is disposed on the vehicle body of the four-wheel drive vehicle 101. The actuator 55 receives the control signals S ₁ and S ₅ from the ECU ₅ and applies a driving force for operating the first driving force interrupting portion 3 (dog clutch) to the first driving force interrupting portion 3. It is configured. Thereby, the differential case 111 of the front differential 106 and the ring gear 61 of the gear mechanism 6 are intermittently connected.

The actuator 56 is disposed on the vehicle body of the four-wheel drive vehicle 101 in the same manner as the actuator 55 of the first driving force interrupting section 3. Then, the actuator 56 receives the control signals S ₂ and S ₆ from the ECU 5, generates a driving force corresponding to the flow rate of the hydraulic oil supplied to the concave hole 180 a (cylinder), and applies it to the flow rate control valve 37. It is configured. Thereby, in the flow rate control valve 37, the flow rate of the hydraulic oil supplied into the concave hole 180a is set to a flow rate corresponding to the hydraulic pressure that becomes the pressing force P to the piston 9 set in advance.

Then, ECU 5 inputs the output signal S ₄ from the output signal S ₃ and the rotation sensor 16 from the rotation sensor 15 from the two-wheel drive mode of the four-wheel-drive vehicle 101 when switching to the four-wheel drive state, the second drive The control signals S ₁ and S ₂ for executing the connection by the force interrupting section 4 in advance of the connection by the first driving force interrupting section 3 are sent to the actuator 55 and the second driving force interrupting section of the first driving force interrupting section 3, respectively. 4 actuator 56 is configured to output. The control signals S ₁ and S ₂ are output from the ECU 5 after performing calculations according to a program using data stored in advance and input data. The input data includes signals such as wheel speed and steering angle of each wheel.

Further, the ECU 5 cancels the connection by the second driving force interrupting unit 4 when the four-wheel driving vehicle 101 is traveling from the four-wheel driving state to the two-wheel driving state. Control signals S ₅ and S ₆ for execution prior to release are output to the actuator 55 of the first driving force interrupting unit 3 and the actuator 56 of the second driving force interrupting unit 4, respectively. ing. The control signals S ₅ and S ₆ are output from the ECU 5 after performing an operation according to a program using previously stored data and the input data. The input data includes signals such as wheel speed and steering angle of each wheel.

[Operation of Driving Force Transmission Device 1]
Next, the operation of the driving force transmission apparatus shown in the first embodiment will be described with reference to FIGS.

  In FIG. 1, during the two-wheel drive of the four-wheel drive vehicle 101, the rotational driving force of the engine 102 is transmitted to the front differential 106 via the transmission 103, and further from the front differential 106 via the pair of front wheel axle shafts 108L and 108R. The power is transmitted to the pair of front wheels 104L and 104R, and the pair of front wheels 104L and 104R are rotationally driven.

  In this case, in FIG. 2, the connection by the first driving force interrupting portion 3 is released, and the propeller shaft 2 is in a non-rotating state. In this state, since the rear wheels 105L and 105R are rotated as driven wheels as the four-wheel drive vehicle 101 travels, the housing 12 and the inner shaft 13 rotate relative to each other, and the sync pump 50 is operating. .

  Therefore, the hydraulic oil in the tank 34 is sucked into the pump space portion from the suction port 502a by the pumping action by the operation of the synchro pump 50, flows through the pump space portion, and is discharged from the discharge port 502b to the hydraulic circuit B for synchronization. It is. The hydraulic oil discharged from the sync pump 50 passes through the check valve 51 and is supplied into the concave hole 180a.

  Here, the flow rate (hydraulic pressure) of the hydraulic oil supplied into the recessed hole 180a is gradually increased by the flow rate control of the flow rate control valve 37 based on the control of the ECU 5, and the piston 9 is moved to the multi-plate clutch 8 side (the inner clutch plate 80 and the inner clutch plate 80). When the outer clutch plate 81 is moved in a direction in which the outer clutch plate 81 is frictionally engaged with each other, the inner clutch plate 80 and the outer clutch plate 81 of the multi-plate clutch 8 are frictionally engaged, and the second driving force interrupting portion 4 is connected. Executed. Accordingly, the rotational torque of the rear wheels 105L and 105R is transmitted to the propeller shaft 2, and the propeller shaft 2 rotates. When the discharge pressure of the hydraulic oil discharged from the synchro pump 50 exceeds the set pressure, the hydraulic oil having a flow rate corresponding to the excess hydraulic pressure passes through the relief valve 36 and is returned to the tank 34.

  Next, the rotation sensor 15 detects the rotation speed of the front differential case 111 and the rotation sensor 16 detects the rotation speed of the propeller shaft 2, and the ECU 5 confirms that the difference between these rotation speeds is “a predetermined threshold value”. And the connection by the 1st driving force interruption part 3 is performed.

  Thereby, switching from the two-wheel drive state to the four-wheel drive state is performed while the four-wheel drive vehicle 101 is traveling.

  On the other hand, at the time of switching from the four-wheel drive state to the two-wheel drive state while the four-wheel drive vehicle 101 is traveling, since the connection by the first driving force interrupting section 3 is performed, the propeller shaft 2 is in a rotating state. In this state, the torque distribution pump 33 is operating by the relative rotation of the propeller shaft 2 and the differential carrier 40.

  For this reason, hydraulic oil in the tank 34 is sucked into the pump space portion from the suction port 332a by the pumping action by the operation of the torque distribution pump 33, flows through the pump space portion, and the torque distribution hydraulic circuit A from the discharge port 333a. Vomited. The hydraulic oil discharged from the torque distribution pump 33 passes through the check valve 35 and is supplied into the concave hole 180a.

  Here, the flow rate (hydraulic pressure) of the hydraulic oil supplied into the recessed hole 180a is gradually decreased by the flow rate control of the flow rate control valve 37 based on the control of the ECU 5, and the piston 9 is opposite to the multi-plate clutch 8 side (inner clutch). (The direction in which the friction engagement between the plate 80 and the outer clutch plate 81 is released) is released, the friction engagement between the inner clutch plate 80 and the outer clutch plate 81 of the multi-plate clutch 8 is released, and the second drive Release of the connection by the force interrupting unit 4 is executed. Accordingly, torque transmission from the propeller shaft 2 to the rear wheel axle shafts 112L and 112R is interrupted. Thereafter, the release of the connection by the first driving force interrupting unit 3 is executed. When the discharge pressure of the hydraulic oil discharged from the torque distribution pump 33 exceeds the set pressure, the hydraulic oil having a flow rate corresponding to the excess hydraulic pressure passes through the relief valve 36 and is returned to the tank 34.

  Thus, switching from the four-wheel drive state to the two-wheel drive state during the traveling of the four-wheel drive vehicle 101 is performed.

  Further, in the four-wheel drive state of the four-wheel drive vehicle 101, the flow rate (hydraulic pressure) of the hydraulic oil supplied into the concave hole 180a is increased or decreased by the flow rate control of the flow rate control valve 37 based on the control of the ECU 5, and the piston 9 is increased. When moved to the plate clutch 8 side or the opposite side, the frictional engagement force between the inner clutch plate 80 and the outer clutch plate 81 of the multi-plate clutch 8 is varied. Thereby, the drive torque of the engine 102 is distributed to the front wheels 104L, 104R side and the rear wheels 105L, 105R side.

[Effect of the embodiment]
According to the embodiment described above, the following effects can be obtained.

  Since an electric pump is not used as the drive source of the second driving force interrupting section 4, it is possible to reduce power consumption when switching the driving state and when distributing the front-rear torque in the four-wheel driving state, thereby reducing the cost. Can be planned.

  As mentioned above, although the driving force transmission device of the present invention has been described based on the above embodiment, the present invention is not limited to the above embodiment, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

(1) In the above embodiment, the case where the synchro pump 50 is operated by the relative rotation of the housing 12 (front housing 18) and the inner shaft 13 has been described, but the present invention is not limited to this, and the four-wheel As two members having a rotational difference when the driving vehicle 101 is driven by two wheels, for example, a sync pump may be operated by relative rotation of a differential carrier and an axle shaft.

(2) Although the case where the synchro pump 50 as the first pump is a non-electric pump has been described in the above embodiment, the present invention is not limited to this, and the electric pump or the electromagnetic pump is used as the sync pump. Even if a driving mechanism such as a clutch is used, since the torque distribution pump is provided, a large driving force is not required, so that the intended purpose of reducing the cost can be achieved.

(3) In the above embodiment, the case where the driving force transmission device 1 is configured by arranging the housing 12 and the inner shaft 13 in the second driving force interrupting portion 4 has been described, but the present invention is limited to this. The driving force transmission device is configured by arranging the housing and the inner shaft in the first driving force interrupting portion, or the housing and the inner shaft in the first driving force interrupting portion and the second driving force interrupting portion, respectively. May be. That is, in short, the present invention provides a driving force transmission device by arranging a pair of rotating members that can rotate relative to each other in at least one of the first driving force interrupting portion and the second driving force interrupting portion. It may be configured.

  DESCRIPTION OF SYMBOLS 1 ... Driving force transmission apparatus, 2 ... Propeller shaft, 20 ... Shaft part, 21 ... Connection part, 3 ... 1st driving force interruption part, 4 ... 2nd driving force interruption part, 5 ... ECU, 6 ... Gear mechanism , 60 ... Drive pinion, 61 ... Ring gear, 7 ... Gear mechanism, 70 ... Drive pinion, 71 ... Ring gear, 8 ... Multi-plate clutch, 80 ... Inner clutch plate, 80a ... Straight spline fitting part, 81 ... Outer clutch plate, DESCRIPTION OF SYMBOLS 9 ... Piston, 9a ... Pressure application part, 12 ... Housing, 13 ... Inner shaft, 13a-13c ... trunk | drum, 13d ... Shaft part, 15, 16 ... Rotation sensor, 17 ... Pushing member, 17a ... Straight spline fitting part , 18 ... front housing, 18a ... trunk, 180a ... concave hole, 18b ... trunk, 18c ... trunk, 180c oil passage, 181c ... concave hole, 182c Projection, 19 ... rear housing, 19a ... hole, 190a ... straight spline fitting part, 19b, 19c ... hole, 30, 31 ... tapered roller bearing, 32 ... cover member, 33 ... pump for torque distribution, 330 331 ... Gears, 332 ... Side plate, 332a ... Suction port, 333 ... Side plate, 333a ... Discharge port, 34 ... Tank, 35 ... Check valve, 36 ... Relief valve, 37 ... Flow control valve, 38, 39 ... Sealing mechanism, 40 ... differential carrier, 400 ... first carrier element, 400a ... shaft insertion hole, 401 ... second carrier element, 401a ... shaft insertion hole, 402 ... third carrier element, 41, 42 ... sealing mechanism, 43 ... Ball bearing, 44, 45 ... retaining ring, 46 ... spring receiving member, 46a ... flange, 47 ... retaining ring, 48, 49 ... sealing member 50 ... Synchro pump, 51 ... Check valve, 52 ... Ball bearing, 53 ... Needle roller bearing, 54 ... Retaining ring, 500, 501 ... Gear, 502 ... Side plate (body 18c of front housing 18), 502a ... Suction port 502b ... discharge port 503 ... side plate 55, 56 ... actuator, 100 ... return spring, 101 ... four-wheel drive vehicle, 102 ... engine, 103 ... transmission, 104L, 104R ... front wheel, 105L, 105R ... rear Wheel 106, front differential, 107 rear differential, 108L, 108R front axle shaft 109L, 109R side gear 110 pinion gear 111 front differential case 112L, 112R rear axle shaft 113L 113R Side gear, 114 ... Pinion gear, 115 ... Pinion gear support member, 116 ... Rear differential case, 117, 118 ... Tapered roller bearing, 119, 120 ... Retaining ring, 130 ... Gear support member, A ... Hydraulic circuit for torque distribution, B ... Hydraulic circuit for synchro , O ... rotation axis

Claims (5)

A driving force transmission shaft that receives driving force of a driving source in a four-wheel drive vehicle and transmits the driving force from the main driving wheel side to the auxiliary driving wheel side;
The driving force transmission shaft and the driving source side are connected so as to be intermittent, and a first driving force interrupting portion disposed on the main driving wheel side;
A second driving force interrupting portion that is disposed on the auxiliary driving wheel side of the first driving force interrupting portion and connects the driving force transmission shaft and the auxiliary driving wheel side;
A pair of rotating members that are arranged in at least one of the second driving force interrupting portion and the first driving force interrupting portion and are rotatable relative to each other;
A first pump that operates by relative rotation of the pair of rotating members, and a pump device that has a second pump that operates by relative rotation of the driving force transmission shaft and the vehicle body side,
The said pump apparatus gives the discharge pressure for operating the clutch which said 1st pump and said 2nd pump interpose between said pair of rotation members to a piston. Driving force transmission apparatus.   The driving force transmission device according to claim 1, wherein the pump device has a flow rate of hydraulic oil corresponding to the discharge pressure controlled by a flow rate control valve.   2. The driving force transmission device according to claim 1, wherein one of the pair of rotating members is connected to the driving force transmitting shaft side and the other rotating member is connected to the auxiliary driving wheel side.   The pair of rotating members is arranged such that a differential for distributing the driving force to the pair of auxiliary driving wheels on the auxiliary driving wheel side is interposed between the one rotating member and the driving force transmission shaft. Item 4. The driving force transmission device according to Item 3.   2. The pump device according to claim 1, wherein the first pump is disposed between the pair of rotating members, and the second pump is disposed between the driving force transmission shaft and the vehicle body side. 2. The driving force transmission device according to 2.

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