JP6225680B2 - Driving force transmission control device - Google Patents

Description

  The present invention relates to a driving force transmission control device that transmits a driving force between rotating members.

  2. Description of the Related Art Conventionally, there is known a driving force interrupting device that is mounted on a four-wheel driving vehicle that can switch between a four-wheel driving state and a two-wheel driving state, and that can intermittently transmit driving force between rotating members (for example, Patent Documents). 1).

  A driving force transmission device described in Patent Document 1 includes an electromagnetic coil that generates magnetic force, an inner shaft that rotates by receiving a driving force from a driving source of a vehicle, and a clutch that is connected to driving wheels and can rotate relative to the inner shaft. A housing, an inner clutch plate coupled to the inner shaft so as not to rotate relative to the clutch housing, an outer clutch plate coupled to the clutch housing so as not to rotate relative to the clutch housing, and a ring lamp coupled to the inner shaft so as not to rotate relative to the inner shaft but move axially. And have. A dog clutch is formed in each of the clutch housing and the ring ramp, and the clutch housing and the inner shaft are connected to each other so as to transmit torque by meshing the dog clutch. Lubricating oil for lubricating frictional sliding between the inner clutch plate and the outer clutch plate is enclosed in the clutch housing.

  When switching from the two-wheel drive state to the four-wheel drive state, the ring ramp is moved to the clutch housing side by the magnetic force generated by the electromagnetic coil, and the inner clutch plate and the outer clutch plate are frictionally engaged with each other. The rotation of the inner shaft and the rotation of the inner shaft are synchronized. Thereafter, the magnetic force is increased and the ring ramp is further moved in the axial direction toward the clutch housing, whereby the dog clutch is engaged and the driving force is transmitted from the inner shaft to the clutch housing.

  When switching from the four-wheel drive state to the two-wheel drive state, the energization of the electromagnetic coil is cut off, so that the ring lamp moves to the opposite side of the clutch housing, the dog clutch is disengaged, and the driving force is reduced. Transmission is interrupted.

JP 2010-25170 A

  By the way, the viscosity of the lubricating oil that lubricates sliding between members increases with a decrease in temperature. As described in Patent Document 1, when a driving force interrupting device in which lubricating oil is interposed between clutch plates is used for transmission of driving force in a vehicle, the lubricating oil is used, for example, when starting an engine in a cold region. The drag torque increases due to the viscosity of the lubricating oil when the temperature of the oil is low, which may lead to deterioration of fuel consumption. Further, when a large gap is formed between the clutch plates in order to reduce drag torque, the responsiveness at the time of transition from the driving force cutoff state to the transmission state is lowered.

  Therefore, an object of the present invention is to provide a driving force transmission control device that can suppress the generation of drag torque when the temperature of the lubricating oil is low while suppressing a decrease in responsiveness.

  In order to achieve the above object, the present invention is a driving force transmission control device capable of switching between a connected state and a non-connected state in which the first rotating member and the second rotating member are connected so as to transmit torque, A second engagement portion that meshes with a first engagement portion provided on the first rotation member, and a second friction portion that frictionally slides on a first friction portion provided on the first rotation member. A moving member coupled to the rotating member so as to be axially movable and relatively non-rotatable, at least a part of the first rotating member and the second rotating member, and the moving member, the first friction portion And a housing enclosing lubricating oil interposed between the second friction portion, an electromagnetic coil that is held in the yoke and generates a magnetic force by energization, a control unit that controls energization to the electromagnetic coil, Axial movement to the yoke side by magnetic force And a positioning mechanism capable of positioning the moving member at a plurality of positions in the axial direction in response to axial movement of the armature, the positioning mechanism including the first meshing portion and the second meshing The moving member at a first position where the first and second friction portions slide, and a plurality of positions between the first position and the second position. The controller can position the moving member such that the lower the temperature of the lubricating oil, the wider the distance between the first friction part and the second friction part in the disconnected state. A driving force transmission control device for positioning is provided.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the drag torque in case the temperature of lubricating oil is low temperature can be suppressed, suppressing the fall of responsiveness.

It is a schematic block diagram which shows the example of a schematic structure of the four-wheel drive vehicle which concerns on embodiment. It is sectional drawing of the driving force transmission apparatus which concerns on embodiment of this invention. It is a perspective view which shows an armature. It is a perspective view which shows the some latching | locking part provided in the 2nd housing member. It is a top view which shows a cam member. The cam member is shown, (a) is a plan view of the cam member, (b) is a perspective view showing a part of the cam member. (A)-(d) is a schematic diagram of the cam member shown in order to demonstrate operation | movement of a positioning mechanism, the press protrusion of an armature, and a latching | locking part. (A)-(d) is a schematic diagram of the cam member, the armature pressing protrusion, and the locking portion shown to explain the operation of the positioning mechanism when the driving force transmission device transitions from the unconnected state to the connected state. It is. It is a flowchart which shows the specific example of the process at the time of transfering from a four-wheel drive state to a two-wheel drive state. It is a flowchart which shows the specific example of the process at the time of transfering from a two-wheel drive state to a four-wheel drive state. It is a schematic diagram for demonstrating operation | movement with a positioning mechanism and a 1st friction member and a 2nd friction member. It is an enlarged view of a storage part and its peripheral part. It is a front view which shows a storage part. (A) shows a cross-sectional view of the driving force transmission device when the storage portion stores the lubricating oil, and (b) shows a cross section of the driving force transmission device when the storage portion allows the lubricating oil to flow out. FIG.

[Embodiment]
FIG. 1 is a configuration diagram showing an outline of a four-wheel drive vehicle equipped with a driving force transmission control device according to a first embodiment of the present invention.

(Configuration of four-wheel drive vehicle 200)
The four-wheel drive vehicle 200 includes a driving force transmission system 201, a driving force transmission control device 2 having a driving force transmission device 1 and a control device 9, an engine 202 as a driving source, a transmission 203, and main driving wheels. Front wheels 204L and 204R, and rear wheels 205L and 205R as auxiliary drive wheels. In FIG. 1, the letter “L” in the code indicates the left side with respect to the forward direction of the four-wheel drive vehicle 200, and the letter “R” indicates the right side with respect to the forward direction of the four-wheel drive vehicle 200.

  The driving force transmission system 201 includes a front wheel side driving force transmission system 201A, a rear wheel side driving force transmission system 201B, and a propeller shaft 20 that connects the front wheel side driving force transmission system 201A and the rear wheel side driving force transmission system 201B. The four-wheel drive vehicle 200 is configured to be switchable from the four-wheel drive state to the two-wheel drive state and from the two-wheel drive state to the four-wheel drive state. The driving force transmission system 201 is disposed along with the front differential 21 and the rear differential 22 on a driving force transmission path from the transmission 203 side of the four-wheel drive vehicle 200 to the rear wheels 205L and 205R.

  A front wheel side gear mechanism 26 including a drive pinion 261 and a ring gear 262 that mesh with each other is disposed at the end of the propeller shaft 20 on the front wheels 204L and 204R side. A rear wheel side gear mechanism 27 including a drive pinion 271 and a ring gear 272 that mesh with each other is disposed at the end of the propeller shaft 20 on the rear wheels 205L and 105R side.

  The front wheel side driving force transmission system 201 </ b> A includes the front differential 21 and the driving force interrupting device 23, and is disposed on the front wheels 204 </ b> L and 204 </ b> R side of the propeller shaft 20. The front differential 21 includes side gears 211L and 211R, a pair of pinion gears 212, a gear support member 213 that rotatably supports the pair of pinion gears 212, and a front differential case 214 that houses the side gears 211L and 211R and the pair of pinion gears 212. And connected to the transmission 203. The side gear 211L is connected to the axle shaft 24L on the front wheel 204L side, and the side gear 211R is connected to the axle shaft 24R on the front wheel 204R side. The pair of pinion gears 212 mesh with the side gears 211L and 211R with their gear axes orthogonal to each other.

  The driving force interrupting device 23 includes a dog clutch having a first spline tooth portion 231, a second spline tooth portion 232, and a sleeve 233. The driving force interrupting device 23 is disposed on the front wheels 204L and 204R side of the four-wheel drive vehicle 200, and the sleeve 233 can be moved forward and backward by an actuator (not shown). The first spline tooth portion 231 is connected to the front differential case 214 and the second spline tooth portion 232 is connected to the ring gear 262 so as not to rotate. The sleeve 233 is connected to the first spline tooth portion 231 and the second spline tooth portion 232 so that the spline can be fitted. With this configuration, the driving force interrupting device 23 connects the propeller shaft 20 and the front differential case 214 via the front wheel side gear mechanism 26 so that they can be intermittently connected.

  The rear wheel side driving force transmission system 201B includes a torque coupling 28 capable of continuously adjusting the transmission torque, the rear differential 22, and the driving force transmission device 1, and includes the propeller shaft 20 on the rear wheels 205L and 205R side. Is arranged. The torque coupling 28 can adjust the torque transmitted from the propeller shaft 20 to the rear differential 22 via the rear wheel side gear mechanism 27, and includes a clutch housing 281 that rotates integrally with the propeller shaft 20, An inner shaft 282 that rotates coaxially with the drive pinion 271, a multi-plate clutch 283 disposed between the clutch housing 281 and the inner shaft 282, and a pusher that presses the multi-plate clutch in accordance with the supplied current. And a pressing mechanism 284 that generates pressure.

  The rear differential 22 houses side gears 221L and 221R, a pair of pinion gears 222, a gear support member 223 that rotatably supports the pair of pinion gears 222, the side gears 221L and 221R, and the pair of pinion gears 222, and is integrated with the ring gear 272. A rotating rear differential case 224; The pair of pinion gears 222 mesh with the side gears 221L and 221R with their gear axes orthogonal to each other. The side gear 221L is connected to the axle shaft 100L on the rear wheel 205L side, and the side gear 221R is connected to the axle shaft 100R on the rear wheel 205R side via the driving force transmission device 1.

  The driving force transmission device 1 can connect and disconnect the side gear 221R of the rear differential 22 and the axle shaft 100R on the rear wheel 205R side. When the connection between the side gear 221R of the rear differential 22 and the axle shaft 100R on the rear wheel 205R side is cut off, the driving force of the engine 202 is not transmitted to the rear wheel 205R, and the side gears 221L and 221R of the rear differential 22 and a pair of When the pinion gear 222 idles, the driving force is not transmitted to the rear wheel 205L, and the two-wheel driving state in which the driving force of the engine 202 is transmitted only to the front wheels 204L and 204R is established.

  On the other hand, when the side gear 221R of the rear differential 22 and the axle shaft 100R on the rear wheel 205R side are connected, the driving force of the engine 202 is transmitted to the rear wheel 205R and the rear wheel via the side gear 221L of the rear differential 22 is connected. The driving force is also transmitted to 205L. Thereby, the four-wheel drive vehicle 200 will be in a four-wheel drive state.

  In the two-wheel drive state, the driving force transmission in the driving force transmission device 1 is interrupted, and the driving force in the driving force interrupting device 23 is also interrupted. As a result, when the four-wheel drive vehicle 200 travels in a two-wheel drive state, the rotation of the propeller shaft 20 stops, and the unillustrated bearing, front wheel side gear mechanism 26 and the like that support the rotation of the propeller shaft 20 are used. Rotational resistance is suppressed and fuel efficiency is improved.

  When shifting from the two-wheel drive state to the four-wheel drive state, the rear wheel 205R is first connected via the drive force transmission device 1 and the torque coupling 28 while the transmission of the drive force in the drive force interrupting device 23 is cut off. Is transmitted from the rear differential 22 to the propeller shaft 20. At this time, the torque transmitted to the propeller shaft 20 is a relatively small torque that can rotate the propeller shaft 20 that has been stopped. When the propeller shaft 20 rotates and the rotation of the first spline tooth portion 231 and the second spline tooth portion 232 of the driving force interrupting device 23 is synchronized, both the spline tooth portions are connected by the sleeve 233. As a result, the driving force of the engine 202 can be transmitted to the rear wheel side driving force transmission system 201B via the propeller shaft 20.

  The control device 9 includes a storage unit 91 including storage elements such as a ROM (Read Only Memory) and a RAM (Random Access Memory), a CPU (Central Processing Unit) that operates according to a program stored in the storage unit 91, and the like. And a current output circuit 93 that supplies a current corresponding to the command value obtained by the arithmetic processing of the control unit 92 to an electromagnetic coil 3 (to be described later) of the driving force transmission device 1. The controller 92 controls the driving force transmission device 1 by turning on and off the current output from the current output circuit 93. The control device 9 also has a configuration for controlling the torque coupling 28. However, since this configuration is the same as a known one, the description thereof is omitted.

(Configuration of the driving force transmission device 1)
FIG. 2 is a cross-sectional view showing the driving force transmission device 1 and its periphery. FIG. 3 is an enlarged view of a main part of FIG.

  In the driving force transmission device 1, torque can be transmitted between the first rotating member 11 connected to the side gear 221R of the rear differential 22 so as not to be relatively rotatable and the second rotating member 12 connected to the axle shaft 100R so as not to be relatively rotatable. Can be switched between a connected state connected to each other and a non-connected state where torque transmission between the first rotating member 11 and the second rotating member 12 is interrupted. In FIG. 2, the connected state is shown above the rotation axis O, and the unconnected state is shown below the rotation axis O.

  The first rotating member 11 and the second rotating member 12 share the rotation axis O and are supported by the housing 10 so as to be relatively rotatable on the same axis. The first rotating member 11 has a spline fitting portion 110f (shown in FIG. 3), which will be described later, as a first engagement portion, and a first friction portion 111b (shown in FIG. 3), which will be described later, as a first friction portion. Is provided.

  As shown in FIG. 2, the driving force transmission device 1 includes a housing 10, a meshing member 14 having a spline fitting portion 142 a as a second meshing portion that meshes with the spline fitting portion 110 f of the first rotating member 11, and a first meshing member 14. The second friction member 17 having the second friction portion 172 that frictionally slides on the first friction portion 111b of the one-rotation member 11, the electromagnetic coil 3 that generates a magnetic force when energized, and the axial movement by the magnetic force of the electromagnetic coil 3 The armature 4, the positioning mechanism 1A capable of positioning the meshing member 14 and the second friction member 17 at a plurality of positions in the axial direction in response to the axial movement of the armature 4, and the lubricating oil L enclosed in the housing 10 And a storage part 7 for storing a part thereof.

  The meshing member 14 and the second friction member 17 are connected to the second rotating member 12 so as to be movable in the axial direction and not relatively rotatable. The meshing member 14 and the second friction member 17 are integrally moved along the rotation axis O. The meshing member 14 and the second friction member 17 are one aspect of the “moving member” of the present invention. The meshing member 14 and the second friction member 17 may be configured as an integral member.

  The housing 10 includes a first housing member 101 and a second housing member 102, and the first housing member 101 and the second housing member 102 are mutually connected by a plurality of bolts 103 (only one bolt 103 is shown in FIG. 2). It is fixed to. The housing 10 houses at least a part of the first rotating member 11 and the second rotating member 12, the meshing member 14, the second friction member 17, the armature 4, and the electromagnetic coil 3. Between the housing 10 and the 1st rotation member 11 and the 2nd rotation member 12, it interposes between the 1st friction member 111 and the 2nd friction member 17 which are mentioned later, and lubricates the lubricous sliding between these members Oil L is enclosed.

  The first rotating member 11 is rotatably supported by a ball bearing 71 disposed between the first rotating member 11 and the first housing member 101. The first rotating member 11 includes a main body 110 formed in a shaft shape, and a first friction member 111 connected to the main body 110 so as to be axially movable and relatively rotatable. The first friction member 111 is connected to one end of the main body 110, and the other end of the main body 110 is connected to the side gear 221 </ b> R of the rear differential 22 so as not to be relatively rotatable.

  The main body 110 includes a shaft portion 110a supported by the ball bearing 71, a projecting portion 110b formed by projecting radially outward from the end portion of the shaft portion 110a, and an end portion on the outer diameter side of the projecting portion 110b. A cylindrical portion 110c extending toward the second rotating member 12 along the rotational axis O, a spline fitting portion 110d formed on the outer periphery of the cylindrical portion 110c, and along the rotational axis O from the end of the cylindrical portion 110c. Furthermore, it has integrally the flange part 110e formed protruding to the 2nd rotation member 12 side, and the spline fitting part 110f formed in the inner periphery of the flange part 110e.

  As shown in FIG. 3, the first friction member 111 includes an annular flange portion 111 a that is externally fitted to the cylindrical portion 110 c of the main body portion 110 and projects outward in the radial direction of the cylindrical portion 110 c, and an outer side of the flange portion 111 a. The first friction part 111b is formed integrally extending from the end on the radial side toward the second rotating member 12 in the axial direction.

  A spline fitting portion 111c that is spline fitted to the spline fitting portion 110d in the cylindrical portion 110c of the first rotating member 11 is formed on the inner periphery of the flange portion 111a. Accordingly, the first friction member 111 is connected to the main body 110 so as to be movable in the axial direction and relatively rotatable.

  A first friction surface 111d that faces the outer peripheral surface 110g of the flange 110e of the main body 110 is formed on the inner periphery of the first friction portion 111b. The first friction surface 111d is a tapered surface inclined in the axial direction so that its inner diameter gradually increases toward the second rotating member 12 in the axial direction.

  The first friction member 111 is pressed in the axial direction toward the second rotating member 12 by an elastic body 113 fitted on the cylindrical portion 110c of the main body 110. The elastic body 113 includes a plurality of disc springs 113a disposed between the pressing member 112 coupled to the outer periphery of the cylindrical portion 110c at the end opposite to the flange portion 111a and the flange portion 111a of the first friction member 111. It is constituted by. In addition, you may comprise the elastic body 113 with a coil spring, for example. The first friction member 111 receives a pressing force in the axial direction from the elastic body 113, is pressed against the second friction member 17, which will be described later, and frictionally slides with the second friction portion 17.

  The second rotating member 12 includes a cylindrical portion 120 formed with an insertion hole 12a through which an axle shaft 100R inserted from an opening 102a formed in the second housing member 102 is inserted, and an outer periphery formed on the outer periphery of the cylindrical portion 120. A spline fitting portion 121 (shown in FIG. 3) and an inner peripheral spline fitting portion 122 (shown in FIG. 3) formed on the inner circumference of the cylindrical portion 120 are integrally provided. The second rotating member 12 and the axle shaft 100R cannot be rotated relative to each other by the spline fitting between the spline fitting portion 100a formed on the outer periphery of the axle shaft 100R and the inner circumferential spline fitting portion 122 of the second rotating member 12. The relative movement in the axial direction is regulated by the snap ring 100b. A seal member 100c seals between the outer peripheral surface of the axle shaft 100R and the inner surface of the opening 102a of the second housing member 102.

  The second rotating member 12 is supported by a ball bearing 72 in which an end small diameter portion 120 b provided at an end portion on the first rotating member 11 side in the axial direction is disposed inside the cylindrical portion 110 c of the first rotating member 11. The other end small diameter portion 120 c provided at the end of the second housing member 102 on the opening 102 a side is supported by a ball bearing 73 disposed between the second housing member 102. Between one end small diameter part 120b and the other end small diameter part 120c, a large diameter part 120a having a larger outer diameter than the one end small diameter part 120b and the other end small diameter part 120c is formed.

  As shown in FIG. 3, the meshing member 14 includes a cylindrical inner cylindrical portion 141, and a bottom portion 143 formed by projecting in the radial direction from the end of the inner cylindrical portion 141 on the second rotating member 12 side in the axial direction. The outer cylindrical portion 142 is formed integrally with the bottom portion 143 so as to extend from the outer diameter side end portion of the bottom portion 143 toward the first rotating member 11 in the axial direction.

  A spline fitting portion 141 a that is spline-fitted to the outer peripheral spline fitting portion 121 of the second rotating member 12 is formed on the inner circumference of the inner cylindrical portion 141. Accordingly, the meshing member 14 is connected to the second rotating member 12 so as to be movable in the axial direction but not to be relatively rotatable.

  Between the inner cylinder part 141 and the outer cylinder part 142, an accommodation hole 14a for accommodating the urging member 15 having elasticity is formed. The urging member 15 is made of, for example, a coil spring, and is disposed between the bottom of the accommodation hole 14 a and the annular receiving member 16 that is spline-fitted to the outer peripheral spline fitting portion 121 of the second rotating member 12. . Movement of the receiving member 16 in a direction away from the meshing member 14 is restricted by a ball bearing 72. The urging member 15 has one end in the axial direction in contact with the receiving member 16 and the other end in the axial direction is in contact with the pressed surface 14b at the bottom of the accommodation hole 14a. The meshing member 14 is always pressed toward the second friction member 17 in the axial direction by the biasing force of the biasing member 15.

  A spline fitting portion 142 a is formed on the outer periphery of the outer cylindrical portion 142. Further, the outer peripheral surface 142b of the outer cylinder portion 142 is opposed to the inner peripheral surface 172b of the second friction portion 172 in the second friction member 17 with a gap.

  When the spline fitting portion 142a is engaged with the spline fitting portion 110f of the first rotating member 11 by the axial movement of the engaging member 14, the first rotating member 11 and the second rotating member 12 are torqued via the engaging member 14. It is connected so that it can be transmitted.

  The second friction member 17 includes a flange portion 171 in contact with an end surface 14c opposite to the axially pressed surface 14b in the bottom portion 143 of the meshing member 14, and a radially outward end portion of the flange portion 171. And a second friction portion 172 formed to extend toward the first rotating member 11 in the direction. The meshing member 14 and the second friction member 17 are always in contact with each other by the urging force of the urging member 15 toward the first rotating member 11 in the axial direction.

  A spline fitting portion 171 a that is spline fitted with the outer circumferential spline fitting portion 121 of the second rotating member 12 is formed on the inner circumference of the flange portion 171. Accordingly, the second friction member 17 is connected to the first rotating member 11 so as to be movable in the axial direction and not relatively rotatable.

  A second friction surface 172 a that frictionally slides with the first friction surface 111 d of the first rotating member 11 is formed on the outer periphery of the second friction portion 172. The second friction surface 172a in the second friction portion 172 is a tapered surface inclined in the axial direction so that the outer diameter gradually becomes smaller toward the first rotating member 11 in the axial direction. The first friction surface 111d and the second friction surface 172a are formed to be parallel to each other, and the second friction member 17 moves to the first rotating member 11 side by the axial movement of the cam member 5 described later. In this case, the second friction surface 172a of the second rotating member 12 is pressed against the first friction surface 111d of the first rotating member 11 and frictionally slides. The cam member 5 moves the second friction member 17 and the meshing member 14 in the axial direction in response to the axial movement of the armature 4 that receives the magnetic force generated by energization of the electromagnetic coil 3.

  As shown in FIG. 2, the electromagnetic coil 3 is formed by winding a winding 32 through which a current supplied from a current output circuit 93 of the control device 9 flows around a bobbin 31 made of resin. The electromagnetic coil 3 is held by an annular yoke 30 made of a ferromagnetic material such as iron, and the yoke 30 is supported by the second housing member 102. The yoke 30 is formed with a plurality of hole portions 30a into which the cylindrical pins 300 arranged so as to be parallel to the rotation axis O are fitted, and one end portion of the pin 300 is inserted into the hole portion 30a. . The second housing member 102 is formed with a plurality of holes 102b into which the other ends of the pins 300 are fitted. Energization of the electromagnetic coil 3 is controlled by the control unit 92 of the control device 9.

  FIG. 4 is a perspective view showing the armature 4. The armature 4 has an annular plate-like main body 40 in which a through hole 4a through which the first rotating member 11 is inserted is formed at the center, and a plurality of ( In this embodiment, six pressing projections 41 are integrally provided. In the main body 40, pin insertion holes 4b through which a plurality of pins 300 (shown in FIG. 1) are inserted are formed around the through hole 4a at a plurality of locations (four locations in the present embodiment). The pressing protrusion 41 has an opposing surface 41a that opposes axial end surfaces 51a to 54a in first to fourth locked portions 51 to 54 of the cam member 5 to be described later, in the thickness direction of the main body 40 (in the rotational axis O). It is formed as an inclined surface inclined with respect to (parallel direction).

  As shown in FIG. 2, the armature 4 is elastically pressed in a direction away from the yoke 30 by a disc spring 301 disposed between the main body 40 and the yoke 30. When the electromagnetic coil 3 is not energized, the armature 4 abuts against the receiving portion 102c of the second housing member 102 by the pressing force of the disc spring 301. When the electromagnetic coil 3 is energized, the armature 4 is attracted to the yoke 30 by the magnetic force. It is done. Further, the rotation of the armature 4 relative to the second housing member 102 and the yoke 30 is restricted by a plurality of pins 300 inserted into the pin insertion holes 4b. Accordingly, the armature 4 moves while being guided by the plurality of pins 300 between the position A in contact with the receiving portion 102 c of the second housing member 102 and the position B in proximity to the yoke 30.

  The positioning mechanism 1A has a first position where the spline fitting portion 110f of the first rotating member 11 and the spline fitting portion 142a of the meshing member 14 mesh with each other, the first friction surface 111d of the first friction member 111 and the second friction member 172. The meshing member 14 and the second friction member 17 can be positioned at a second position where the second friction surface 172a slides and a plurality of positions between the first position and the second position.

  The spline fitting portion 110f of the first rotating member 11 and the spline fitting portion 142a of the meshing member 14 mesh only when the meshing member 14 is positioned at the first position, and the meshing member 14 is positioned at the second position. When the engagement member 14 is positioned at a position between the first position and the second position, the spline fitting portion 110f of the first rotating member 11 and the spline fitting portion 142a of the engagement member 14 Is released.

  Further, the positioning mechanism 1A includes a locking portion 19 (shown in FIG. 2) provided in the second housing member 102 that is not axially movable with respect to the second rotating member 12 and is not relatively rotatable with respect to the armature 4. A cylindrical cam member 5 in which a plurality of locked portions (first to sixth locked portions 51 to 56 described later) locked to the locking portion 19 at different positions in the axial direction are formed. The locking portion 19 is configured to lock other locked portions having different axial positions among the plurality of locked portions in response to the axial movement of the armature 4. The cam member 5 moves in the axial direction together with the second friction member 17 and the meshing member 14. Details of the operation of the positioning mechanism 1A will be described later.

  The cam member 5 is externally fitted to the large-diameter portion 120 a in the cylindrical portion 120 of the second rotating member 12. The cam member 5 is fitted in the cylindrical portion 120 of the second rotating member 12 so as to be axially movable and relatively rotatable with respect to the second rotating member 12. A rolling bearing 6 is arranged between the second friction member 17 and the cam member 5. In this embodiment, the rolling bearing 6 is a needle thrust roller bearing. The second friction member 17 is disposed closer to the first rotating member 11 than the rolling bearing 6, and the cam member 5 is disposed closer to the locking portion 19 than the rolling bearing 6.

  The cam member 5 receives the pressing force of the urging member 15 as an urging force in the axial direction from the meshing member 14 and the second friction member 17 to the side of the plurality of locking portions 19 via the rolling bearing 6. In the present embodiment, the plurality of locking portions 19 are provided integrally with the second housing member 102, but the plurality of locking portions 19 may be separate from the second housing member 102.

  FIG. 5 is a perspective view showing a plurality of locking portions 19 provided in the second housing member 102.

  The second housing member 102 is formed with a through hole 102d through which the second rotating member 12 is inserted, and the plurality of locking portions 19 protrude from the inner peripheral surface of the through hole 102d toward the first rotating member 11 side. And it protrudes to the cam member 5 side along the rotation axis O. The plurality of locking portions 19 are provided at equal intervals along the circumferential direction of the through hole 102 d, and the number thereof is the same as the number of the pressing protrusions 41 of the armature 4. Similarly to the opposing surface 41 a of the pressing protrusion 41 of the armature 4, the locking portion 19 has a tip end surface 19 a that opposes axial end surfaces 51 a to 56 a in locked portions 51 to 56 of the cam member 5 described later. It is formed as an inclined surface inclined with respect to a direction parallel to O.

  FIG. 6 shows the cam member 5, (a) is a plan view of the cam member 5 viewed from the side of the plurality of locking portions 19 along the rotation axis O, and (b) is a perspective view showing a part of the cam member 5. FIG.

  The cam member 5 is formed with a plurality of locked portions that are locked to the locking portion 19 at different positions in the axial direction, adjacent to each other in the circumferential direction. In the present embodiment, the plurality of locked portions include first to sixth locked portions 51 to 56. Six sets of these first to sixth locked portions 51 to 56 are formed along the circumferential direction at the end opposite to the base end surface 5a with which the rolling bearing 6 abuts.

  The first to sixth locked portions 51 to 56 in each set are adjacent to the first locked portion 51 when the cam member 5 is viewed clockwise from the direction of the rotation axis O. The second locked portion 52 is formed, the third locked portion 53 is formed adjacent to the second locked portion 52, and the fourth locked portion 53 is adjacent to the third locked portion 53. A locking part 54 is formed, a fifth locked part 55 is formed adjacent to the fourth locked part 54, and a sixth locked part is adjacent to the fifth locked part 55. A portion 56 is formed. A wall portion 57 protruding in the axial direction is formed at the end of the sixth locked portion 56 opposite to the fifth locked portion 55.

  The first to sixth locked portions 51 to 56 are different from each other in the axial direction of the cam member 5, and the second locked portion 52 is closer to the base end surface 5 a than the first locked portion 51. The third locked portion 53 is further away from the base end surface 5 a than the second locked portion 52. Similarly, the fourth locked portion 54, the fifth locked portion 55, and the sixth locked portion 56 are formed so as to be sequentially separated from the base end surface 5a.

  The axial end surfaces 51 a to 56 a of the first to sixth locked portions 51 to 56 are inclined with respect to the circumferential direction of the cam member 5. More specifically, the axial end surface 51a of the first locked portion 51 is inclined so that the end on the second locked portion 52 side approaches the base end surface 5a, and the second locked portion The axial end surface 52a of 52 is inclined so that the end on the third locked portion 53 side is closer to the base end surface 5a, and the axial end surface 53a of the third locked portion 53 is the fourth locked surface. The end portion on the side of the portion 54 is inclined so as to approach the base end surface 5a, and the end surface 54a in the axial direction of the fourth locked portion 54 is closer to the base end surface 5a on the end portion on the fifth locked portion 55 side. The axial end surface 55a of the fifth locked portion 55 is inclined so that the end on the sixth locked portion 56 side is closer to the base end surface 5a. The axial end surface 56a is inclined so as to approach the base end surface 5a toward the end on the wall 57 side.

  The wall 57 has an axial end surface 57a inclined in the same direction as the axial end surfaces 51a to 56a. Further, the wall portion 57 has one side surface 57 b in the circumferential direction facing the sixth locked portion 56.

  The opposing surface 41a of the pressing projection 41 of the armature 4 and the distal end surface 19a of the locking portion 19 abut on the axial end surfaces 51a to 56a of the first to sixth locked portions 51 to 56. The facing surface 41a of the armature 4 is in contact with the radially outer portion of the cam member 5 on the axial end surfaces 51a to 56a, and the distal end surface 19a of the locking portion 19 is the diameter of the cam member 5 on the axial end surfaces 51a to 56a. It abuts against the inner part in the direction. The cam member 5 receives an urging force in the axial direction by which the axial end surfaces 51 a to 56 a are pressed against the pressing protrusion 41 and the locking portion 19 of the armature 4 by the urging member 15.

  When the locking portion 19 locks the first locked portion 51, the distance between the distal end surface 19a and the proximal end surface 5a of the locking portion 19 is the shortest. Moreover, when the latching | locking part 19 latches the 6th to-be-latched part 56, the space | interval of the front end surface 19a of the latching | locking part 19 and the base end surface 5a becomes the longest.

  When the locking portion 19 locks the first locked portion 51, the spline fitting portion 142 a of the meshing member 14 is a flange portion of the first rotating member 11 as shown above the rotation axis O in FIG. 2. 110e completely engages with the spline fitting portion 110f. In a state where the locking portion 19 locks the second locked portion 52, the spline fitting portion 142 a of the meshing member 14 is a part of the spline fitting portion 110 f in the flange portion 110 e of the first rotating member 11. Will be engaged. That is, the position of the meshing member 14 when the locking part 19 is locked to the first locked part 51 or the second locking part 52 corresponds to the first position in the positioning mechanism 1A described above.

  When the locking part 19 locks the third to sixth locked parts 53 to 56, the spline fitting part 110 f in the spline fitting part 142 a of the meshing member 14 and the flange part 110 e of the second rotating member 12. Is in a released state. Further, when the locking portion 19 locks the sixth locked portion 56, the second friction surface 172a of the second friction member 17 is the first friction member 17 as shown below the rotation axis O in FIG. The friction member 111 is pressed against the first friction surface 111d to be in a state of friction sliding. That is, the position of the meshing member 14 when the locking portion 19 locks the sixth locked portion 56 corresponds to the second position in the positioning mechanism 1A.

(Operation of positioning mechanism 1A)
Next, the operation of the positioning mechanism 1A will be described with reference to FIGS.

  7A to 7D are schematic views showing a state in which the cam member 5 is viewed from the outer side in the radial direction together with the pressing protrusion 41 and the locking portion 19 of the armature 4. FIG. 8 is a schematic diagram of the cam member 5, the pressing protrusion 41 of the armature 4, and the locking portion 19 for explaining the operation of the positioning mechanism 1 </ b> A when the driving force transmission device 1 shifts from the non-connected state to the connected state. FIG.

  FIG. 7A shows a first state in which the locking portion 19 locks the first locked portion 51 and the armature 4 is at the position A. In this first state, the urging force of the urging member 15 causes the axial end surface 51 a of the first locked portion 51 to be pressed against the distal end surface 19 a of the locking portion 19, and the facing surface of the pressing protrusion 41 of the armature 4. It faces 41a. Further, the locking portion 19 abuts on the circumferential side surface 51b of the first locked portion 51, and the pressing protrusion 41 of the armature 4 is axially spaced from the side surface 51b in the circumferential direction of the cam member 5 in the axial direction end surface 51a. Opposite to. A side surface 51 b of the first locked portion 51 is a step surface formed between the first locked portion 51 and the second locked portion 52, and is parallel to the axial direction of the cam member 5. It is a flat surface. In the first locked portion 51, the angle formed between the axial end surface 51a and the side surface 51b is an acute angle.

  FIG. 7B shows a second state where the electromagnetic coil 3 is energized and the armature 4 is moved to the position B from the first state shown in FIG. In the armature 4, the opposing surface 41 a of the pressing protrusion 41 abuts on the axial end surface 51 a during the transition from the first state to the second state, and the pressing protrusion 41 presses the cam member 5 toward the meshing member 14. Further, in this second state, the state in which the locking portion 19 is in contact with the side surface 51b of the first locked portion 51 is released, and the cam member 5 is the axial end surface of the first locked portion 51. By sliding between 51a and the opposed surface 41a of the pressing projection 41 of the armature 4, the first predetermined angle rotates in the arrow X direction. By the rotation of the cam member 5, the side surface 51 b of the first locked portion 51 comes into contact with the side surface 41 b of the pressing protrusion 41 of the armature 4.

That is, the armature 4 moves the cam member 5 to the meshing member 14 side by moving the cam member 5 to the meshing member 14 side by performing a pushing operation of pushing the cam member 5 to the meshing member 14 side by moving in the axial direction from the position A to the position B. Is rotated by a first predetermined angle. The first predetermined angle is an angle corresponding to the distance d ₁ of the gap between the pressing projection 41 of the armature 4 shown in FIG. 7 (a) and the side surface 51b of the first engaged portion 51.

  When the armature 4 is at the position B, the distal end surface 19a of the locking portion 19 is opposed to the axial end surface 52a with a gap between it and the second locked portion 52. That is, when the armature 4 moves to the position B, the cam member 5 rotates by the first predetermined angle, the pressing protrusion 41 contacts the side surface 51b, and the tip surface 19a of the locking portion 19 is the first locked portion 51. It faces a part of the axial end surface 52a of the second locked portion 52 adjacent to the second locked portion 52.

  FIG. 7C shows a third state in which the energization of the electromagnetic coil 3 is interrupted and the armature 4 is returning from the position B to the position A. In the third state, the front end surface 19 a of the locking portion 19 abuts on the axial end surface 52 a of the second locked portion 52. A rotational force in the direction of arrow X acts on the cam member 5 due to the contact between the distal end surface 19a of the locking portion 19 and the axial end surface 52a of the second locked portion 52. Is restricted by the contact between the side surface 41 b of the pressing projection 41 of the armature 4 and the side surface 51 b of the first locked portion 51.

7D, the armature 4 returns to the position A, and the cam member 5 rotates in the arrow X direction until the side surface 19b of the second locking portion 52 contacts the side surface 19b of the locking portion 19. The fourth state is shown. In this fourth state, the cam member 5 receives the urging force of the urging member 15 and slides between the axial end surface 52a of the second locked portion 52 of the cam member 5 and the distal end surface 19a of the locking portion 19. 5 rotates with respect to the locking portion 19 by a second predetermined angle. Thereby, the locking part 19 locks the second locked part 52. The second predetermined angle is an angle corresponding to the distance d ₂ between the side surface 52b and the engaging portion 19 of the second engaged portion 52 in the third state shown in FIG. 7 (c). That is, the movement of the armature 4 from the position B to the position A further rotates the cam member 5 by the second predetermined angle, so that the locking portion 19 is adjacent to the first locked portion 51 and the second locked portion 52. Lock.

  In the positioning mechanism 1 </ b> A, the armature 4 reciprocates a plurality of times between the position A and the position B, so that the cam member 5 moves the meshing member 14 in the axial direction against the biasing force of the biasing member 15. In the present embodiment, since the cam member 5 has six locked portions (first to sixth locked portions 51 to 56) formed in a step shape, energization to the electromagnetic coil 3 and energization interruption are performed. Is performed five times, and the armature 4 reciprocates between the position A and the position B five times, so that the locking portion 19 locks the first locked portion 51 to the sixth locked portion 56. The cam member 5 is rotated to the position where it is locked.

As shown in FIG. 7 (a), the distance from the base end surface 5a to the axial end face 51a of the first engaged portion 51 and d _3, the axial direction from the proximal end surface 5a sixth engaged portion 56 When the distance to the end face 56a and d _4, the distance d ₄ is longer than the distance d _3, the cam member 5 moves forward and backward the distance d ₄ and the distance in the axial direction in a range corresponding to a difference between the d ₃ .

  When the locking portion 19 locks the sixth locked portion 56 and the meshing member 14 is in the second position, the second friction surface 172 a of the second friction member 17 is the first friction member 111. The friction surface 111d is pressed in the axial direction. In this case, the elastic body 113 is compressed in the axial direction, and the first friction surface 111 d of the first friction member 111 and the second friction surface 172 a of the second friction member 17 are pressed against each other by the restoring force of the elastic body 113. Thereby, when the 1st rotation member 11 and the 2nd rotation member 12 are rotating relatively with a rotational speed difference, the difference between the rotation speed of the 1st rotation member 11 and the rotation speed of the 2nd rotation member 12 is obtained. The frictional force (friction torque) between the first friction surface 111d and the second friction surface 172a gradually decreases. And the rotation of the 1st rotation member 11 and the rotation of the 2nd rotation member 12 synchronize with this frictional force.

  FIG. 8 shows a state in which the locking portion 19 shifts from the state of locking the sixth locked portion 56 to the first locked portion 51, and the meshing member 14 moves in the axial direction together with the cam member 5. FIG. 6 is a schematic diagram for explaining an operation when the driving force transmission device 1 shifts from a non-connected state to a connected state.

  FIG. 8A shows a state in which the locking portion 19 locks the sixth locked portion 56 and the armature 4 is at the position A. In this state, the locking portion 19 contacts the axial end surface 56 a of the sixth locked portion 56 and the circumferential side surface 57 b of the wall portion 57.

  FIG. 8B shows a state where the armature 4 has moved to the position B from the state shown in FIG. In the process of moving the armature 4 from the position A to the position B, the pressing protrusion 41 presses and moves the cam member 5 toward the meshing member 14 by the pushing operation. At this time, the second friction member 17 also moves in the axial direction due to the pressing force accompanying the axial movement of the cam member 5, so that the elastic body 113 is further compressed. Further, the state in which the locking portion 19 is in contact with the circumferential side surface 57b of the wall portion 57 is released by this pushing operation, so that the cam member 5 is rotated by the first predetermined angle in the arrow X direction.

  FIG. 8C shows a state where the armature 4 is returning to the position A from the state shown in FIG. In this state, the distal end surface 19 a of the locking portion 19 abuts on the axial end surface 57 a of the wall portion 57, and a rotational force in the arrow X direction acts on the cam member 5.

FIG. 8D shows a state in which the armature 4 has returned to the position A and rotated in the arrow X direction until the locking portion 19 locks the first locked portion 51. In the process of transition from the state shown in FIG. 8 (c) to the state shown in FIG. 8 (d), the cam member 5 is a distance d ₃ and the distance in the axial direction over the entire range corresponding to the difference between the d ₄ The spline fitting part 142a of the meshing member 14 meshes with the spline fitting part 110f in the flange part 110e of the first rotating member 11 with great displacement.

  Thus, when the cam member 5 moves in the axial direction on the opposite side to the direction in which the armature 4 moves in the axial direction by the magnetic force, the spline fitting portion 142a of the meshing member 14 is rotated by the urging force of the urging member 15 in the first rotation. It engages with the spline fitting portion 110f in the flange portion 110e of the member 11. More specifically, the meshing member 14 includes a sixth locked portion 56 in which the locking portion 19 is formed at a position farthest from the meshing member 14 among the first to sixth locked portions 51 to 56. When the first locked portion 51 formed at the position closest to the meshing member 14 is unlocked, the spline fitting portion 142a of the meshing member 14 is biased by the biasing force of the biasing member 15. Meshes with the spline fitting portion 110f of the first rotating member 11, and the first rotating member 11 and the second rotating member 12 are connected to be able to transmit torque.

(Control of the driving force transmission device 1)
As the temperature of the lubricating oil L is lower, the control unit 92 of the control device 9 has a distance between the first friction portion 111b of the first friction member 111 and the second friction portion 172 of the second friction member 17 in the disconnected state. The second friction member 17 is positioned by controlling the driving force transmission device 1 so as to widen. More specifically, when the temperature of the lubricating oil L is in an extremely low temperature range, the engaging member 14 is positioned in a state where the locking portion 19 locks the third locked portion 53, and the lubricating oil L When the temperature of the engagement member 14 is in a low temperature range, the engagement member 14 positions the engagement member 14 in a state where the engagement portion 19 engages the fourth engagement portion 54. Further, when the temperature of the lubricating oil L is in a normal high temperature range (normal temperature or high temperature range), the engaging member 19 positions the meshing member 14 with the fifth locked portion 55 being locked. Hereinafter, the processing contents executed by the control unit 92 and the operation of the positioning mechanism 1A will be described with reference to FIGS.

  FIG. 9 is a flowchart illustrating a specific example of the process executed when the control unit 92 shifts from the four-wheel drive state to the two-wheel drive state. FIG. 10 illustrates the process from the two-wheel drive state to the four-wheel drive. It is a flowchart which shows the specific example of the process at the time of shifting to a state. The control unit 92 repeatedly executes the processes shown in these flowcharts at a predetermined control cycle. FIGS. 11A to 11F are schematic diagrams illustrating an operation example of the positioning mechanism 1 </ b> A in conjunction with the process executed by the control unit 92.

  When the four-wheel drive vehicle 200 is in a four-wheel drive state, that is, the first rotating member 11 and the second rotating member are connected, the driving force of the engine 202 is driven from the side gear 221R of the rear differential 22 to the axle shaft 100R. When being transmitted via the force transmission device 1, the controller 92 determines whether or not to switch from the four-wheel drive state to the two-wheel drive state (step S10). This determination is made based on, for example, information on a switch operation by the driver and a running state (rotational difference between front and rear wheels, an acceleration operation amount by an accelerator pedal, a steering angle of a steering wheel, or the like). When the four-wheel drive vehicle 200 is in the four-wheel drive state, the locking portion 19 locks the first locked portion 51.

  If it is determined that switching from the four-wheel drive state to the two-wheel drive state should not be performed (step S10: No), the control unit 92 ends the process as it is. On the other hand, when it is determined that switching from the four-wheel drive state to the two-wheel drive state should be performed (step S10: Yes), the control unit 92 estimates the temperature of the lubricating oil L (step S11). The temperature of the lubricating oil L can be calculated based on, for example, the outside air temperature calculated by the outside air temperature sensor, the integrated value of the driving force transmitted via the driving force transmission device 1 over a predetermined period, or the like. Further, the temperature of the lubricating oil L may be obtained from an output signal of a temperature sensor provided in the housing 10.

  Next, the controller 92 determines whether or not the temperature of the lubricating oil L estimated in step S10 is in the normal high temperature range (step S12). This determination is made based on whether or not the temperature of the lubricating oil L is, for example, 25 ° C. or higher. That is, when the temperature of the lubricating oil L is normal temperature or high temperature, the result of this determination is Yes.

  When it determines with the temperature of the lubricating oil L being a normal high temperature range (step S12: Yes), the control part 92 performs a 1st electricity supply switching process (step S15). This first energization switching process is a process of repeatedly energizing and deenergizing the electromagnetic coil 3 four times (steps S151 to S154).

  When the first energization and energization cut-off processing (step S151) is executed, the locking portion 19 is locked to the second locked portion 52, and the spline fitting portion 142a of the meshing member 14 is engaged. It will be in the state which meshed with a part of spline fitting part 110f of the 1st rotation member 11. When the second energization / energization process (step S152) is executed, the locking portion 19 is locked to the third locked portion 53, and the spline fitting portion 142a of the meshing member 14 is engaged. The engagement of the first rotating member 11 with the spline fitting portion 110f is released. The positioning mechanism 1A at this time is shown in FIGS. 13 (a) and 13 (b).

  When the third energization / energization process (step S153) is executed, the engagement portion 19 is engaged with the fourth engaged portion 54, and the meshing member 14 and the second friction member are engaged. 17 moves to the first rotating member 11 side. The positioning mechanism 1A at this time is shown in FIGS. 13 (c) and 13 (d).

  Furthermore, when the fourth energization / energization process (step S154) is executed, the locking portion 19 is locked to the fifth locked portion 55, and the meshing member 14 and the second friction are engaged. The member 17 further moves to the first rotating member 11 side. The positioning mechanism 1A at this time is shown in FIGS. 13 (e) and 13 (f). When the process of step S154 is completed, the control unit 92 stores the positional information of the meshing member 14 and the second friction member 17 at that time in the storage unit 91 (step S20), and ends the process of the flowchart shown in FIG. To do. Therefore, the positions of the meshing member 14 and the second friction member 17 are positioned at the positions shown in FIGS. 13E and 13F until the next four-wheel drive state is reached.

  In the following description, the positions of the meshing member 14 and the second friction member 17 when the second energization / energization process (step S152) is executed are defined as the third position, and the third energization and energization interruption are performed. The position of the meshing member 14 and the second friction member 17 when the above process (step S153) is executed is set to the fourth position, and the meshing when the fourth energization / energization process (step S154) is performed is performed. Let the position of the member 14 and the 2nd friction member 17 be a 5th position. Therefore, information indicating whether the meshing member 14 and the second friction member 17 are positioned from the third position to the fifth position is stored in the storage unit 91. When the temperature of the lubricating oil L is in the normal high temperature range, the meshing member 14 and the second friction member 17 are positioned at the fifth position by the first energization switching process (step S15).

When the second friction member 17 is in the third position, there is a distance h between the first friction surface 111d of the first friction portion 111b of the first rotating member 11 and the second friction surface 172a of the second friction member 17. ₁ gap is formed. When the second friction member 17 in a fourth position, the first friction surface 111d between the second friction surface 172a, a gap of the narrow distance _{h 2} is formed than the distance _{h 1.} Further, the second friction member 17 when in the fifth position, the between the first friction surface 111d second friction surface 172a, a narrower gap distances _{h 3} than the distance _{h 2} is formed. The distances h ₁ , h ₂ , and h ₃ are, for example, 0.5 mm, 0.3 mm, and 0.1 mm, respectively.

  Further, when it is determined in step S12 that the temperature of the lubricating oil L is not in the normal high temperature range (step S12: No), the control unit 92 determines whether or not the temperature of the lubricating oil L is in the low temperature range. (Step S13). This determination is performed based on whether the temperature of the lubricating oil L is, for example, −10 ° C. or higher.

  When it determines with the temperature of the lubricating oil L being a low temperature range (step S13: Yes), the control part 92 performs a 2nd electricity supply switching process (step S16). The second energization switching process is a process of repeatedly energizing and interrupting the electromagnetic coil 3 three times (steps S161 to S163). When the second energization switching process is completed, the control unit 92 stores information indicating the positions (fourth positions) of the meshing member 14 and the second friction member 17 at that time in the storage unit 91 (step S20). The process of the flowchart shown in FIG. Therefore, the meshing member 14 and the second friction member 17 are positioned at the fourth position until the next four-wheel drive state is reached.

  Further, when it is determined in step S13 that the temperature of the lubricating oil L is not in the low temperature range (step S13: No), the control unit 92 determines that the temperature of the lubricating oil L is in the extremely low temperature range, 3 energization switching processing is executed (step S17). The third energization switching process is a process of repeatedly energizing and interrupting the electromagnetic coil 3 twice (steps S171 to S172). When the third energization switching process is completed, the control unit 92 stores information indicating the positions (third positions) of the meshing member 14 and the second friction member 17 at that time in the storage unit 91 (step S20). The process of the flowchart shown in FIG. Therefore, the meshing member 14 and the second friction member 17 are positioned at the third position until the next four-wheel drive state is reached.

  Next, the processing of the control unit 92 and the operation of the positioning mechanism 1A when shifting from the two-wheel drive state to the four-wheel drive state will be described with reference to FIG.

  When the four-wheel drive vehicle 200 is in a two-wheel drive state, that is, when the first rotating member 11 and the second rotating member are not connected and the driving force of the engine 202 is not transmitted to the axle shaft 100R, the control is performed. The unit 92 determines whether or not to perform switching from the two-wheel drive state to the four-wheel drive state (step S21). This determination can be performed based on, for example, switch operation by the driver and information on the running state, similarly to the process in step S10 described above.

  When it is determined that switching from the two-wheel drive state to the four-wheel drive state should not be performed (step S21: No), the control unit 92 ends the process as it is. On the other hand, when it determines with switching to a four-wheel drive state (step S21: Yes), the control part 92 acquires the positional information on the latching | locking part 19 from the memory | storage part 91 (step S22).

  Next, the control unit 92 determines whether or not the position information acquired from the storage unit 91 is the third position (step S23). When the position information is the third position (step S23: Yes), the first information A connection process is executed (step S24). This 1st connection process (step S24) is a process which performs the electricity supply to the electromagnetic coil 3, and the electricity supply interruption | blocking process 3 times (steps S241-S243). Accordingly, the meshing member 14 and the second friction member 17 pass through the fourth position and the fifth position, and the second friction surface 172a of the second friction member 17 is axially directed to the first friction surface 111d of the first friction member 111. Move to the position to be pressed.

  Next, the controller 92 determines whether or not the rotation of the first rotating member 11 and the rotation of the second rotating member 12 are synchronized (step S28). This determination can be made, for example, by comparing the rotational speed of the propeller shaft 20 with the rotational speed of the rear wheel 205R. As a result of the determination, if the rotation of the first rotating member 11 and the rotation of the second rotating member 12 are not synchronized (step S28: No), the determination of step S28 is repeatedly executed.

  On the other hand, if the rotation of the first rotating member 11 and the rotation of the second rotating member 12 are synchronized (step S28: Yes), the electromagnetic coil 3 is energized and de-energized once (step S29). The process of the flowchart shown in FIG. As a result of the processing in step S29, the state in which the locking portion 19 is locked to the sixth locked portion 56 shifts to the state in which the first locked portion 51 is locked, and the biasing force of the biasing member 15 is increased. As a result, the spline fitting portion 142a of the meshing member 14 meshes with the spline fitting portion 110f of the first rotating member 11, and the first rotating member 11 and the second rotating member 12 are connected so as to transmit torque.

  On the other hand, when the position information acquired from the storage unit 91 is not the third position (step S23: No), the control unit 92 determines whether or not the position information acquired from the storage unit 91 is the fourth position (step S23). S25) If the position is the fourth position, the second connection process is executed (step S26). This 2nd connection process (step S26) is a process which performs the electricity supply to the electromagnetic coil 3, and the electricity supply interruption | blocking process twice (steps S261-S262). As a result, the meshing member 14 and the second friction member 17 pass through the fifth position, and the second friction surface 172a of the second friction member 17 is pressed against the first friction surface 111d of the first friction member 111 in the axial direction. Move to. Thereafter, the processes of steps S28 to S29 described above are executed, and the process of the flowchart shown in FIG.

  When the position information acquired from the storage unit 91 is not the fourth position (step S25: No), the control unit 92 executes the energization and de-energization processing for the electromagnetic coil 3 once (step S27), and the meshing member. 14 and the second friction member 17 are moved to a position where the second friction surface 172a of the second friction member 17 is pressed against the first friction surface 111d of the first friction member 111 in the axial direction. Thereafter, the processes of steps S28 to S29 described above are executed, and the process of the flowchart shown in FIG.

(Configuration and operation of storage unit 7)
Next, the configuration and operation of the storage unit 7 will be described with reference to FIGS.

  FIG. 12 is a cross-sectional view showing the configuration of the storage unit 7. FIG. 13 is a front view of the reservoir 7 as viewed from the direction of arrow Z in FIG.

  The storage unit 7 is disposed above the first friction member 111 and the second friction member 17 and can enclose and discharge the main body 71 capable of storing the lubricating oil L and the lubricating oil L stored in the main body 71. It has the cover part 72 and the hinge part 73 which supports the cover part 72 so that opening and closing is possible. The main body 71 of the reservoir 7 is fixed to the end surface of the yoke 30 on the first rotating member 11 side in the axial direction and the inner surface of the housing 10 (first housing member 101). The lid portion 72 is opened and closed by the opening / closing mechanism 70. When the lid portion 72 is in the closed state, the lubricating oil L is stored in the main body portion 71, and when the lid portion 72 is in the open state, the lid portion 72 is stored in the main body portion 71. Lubricating oil L is discharged.

  A plurality of guide portions 101 a that guide the lubricating oil L to the storage portion 7 are provided on the inner surface of the first housing member 101 located above the storage portion 7. The plurality of guide portions 101 a have a triangular shape that protrudes downward as the end surface on the rotation axis O side approaches the yoke 30 side, and the tip portions thereof are located in the main body portion 71 of the storage portion 7. Thereby, the lubricating oil L scattered on the inner surface of the first housing member 101 with the rotation of the first rotating member 11 and the second rotating member 12 is guided by the plurality of guide portions 101 a and stored in the main body portion 71. .

  The opening / closing mechanism 70 of the lid 72 includes a pressing rod 701, a rotating rod 702, a support member 703 fixed to the yoke 30, a connecting portion 704 that connects the pressing rod 701 and the rotating rod 702, and the rotating rod 702. And a support shaft 705 that is rotatably supported by the support member 703. The opening / closing mechanism 70 is operated by the axial movement of the second friction member 17 and the meshing member 14, and when the spline fitting portion 142 a of the first meshing member 14 is meshed with the spline fitting portion 110 f of the first rotating member 11, The lid 72 is opened.

  Fig.11 (a) shows the state of the storage part 7 in a non-connected state, and FIG.11 (b) shows the state of the storage part 7 in a connected state.

  In the two-wheel drive state (non-connected state), the reservoir 7 is in a state where the lid 72 is closed by the weight of the lid 72, and the lubricating oil L is stored in the main body 71. Thereby, the amount of the lubricating oil L existing in the region other than the storage portion 7 in the housing 10 is reduced, and the first friction surface 111d of the first friction portion 111b and the second friction surface 172a of the second friction portion 172 are reduced. The drag torque due to the viscosity of the lubricating oil L interposed therebetween is reduced.

  When the driving force transmission device 1 shifts from the non-connected state to the connected state, the tip of the rotating rod 702 contacts the second friction member 17 and rotates around the support shaft 705, and the pressing rod 701 is covered with the lid portion 72. Is pressed, the lid 72 is opened, and the lubricating oil L stored in the main body 71 is discharged. Thereby, each part (the ball bearing 72, the rolling bearing 6, etc.) of the driving force transmission device 1 is sufficiently lubricated.

(Operation and effect of the embodiment)
According to the embodiment described above, the following operations and effects can be obtained.

(1) In the non-connected state of the driving force transmission device 1, the lower the temperature of the lubricating oil L, the lower the temperature between the first friction surface 111d of the first friction portion 111b and the second friction surface 172a of the second friction portion 172. The second friction member 17 is positioned so as to increase the distance. Thereby, the drag torque between the first friction member 111 and the second friction member 17 is reduced particularly at a low temperature or an extremely low temperature when the viscosity of the lubricating oil L is high. In the present embodiment, since the distance between the first friction part 111b of the first friction member 111 and the second friction part 172 of the second friction member 17 is wider at the extremely low temperature than at the low temperature, this drag torque is More appropriately reduced.

(2) At the time of normal high temperature when the viscosity of the lubricating oil L is lowered, the gap between the first friction surface 111d of the first friction portion 111b and the second friction surface 172a of the second friction portion 172 is lower than at low temperature or extremely low temperature. Since the distance becomes narrow, the transition to the connected state can be performed quickly. That is, according to the present embodiment, by changing the position where the second friction member 17 is positioned according to the temperature of the lubricating oil L, the response at normal temperature (transition from the non-connected state to the connected state). The drag torque at the time of low temperature or extremely low temperature can be reduced while ensuring the speed).

(3) Since the second friction member 17 is positioned by the cam member 5 having a plurality of locked portions (first to sixth locked portions 51 to 56), the positioning accuracy of the second friction member 17 is increased. At the same time, electric power for maintaining the position of the second friction member 17 becomes unnecessary. That is, since it is not necessary to continue energization of the electromagnetic coil 3 after positioning the second friction member 17, it is possible to contribute to power saving and fuel consumption reduction.

(4) Since the first friction surface 111d of the first friction portion 111b and the second friction surface 172a of the second friction portion 172 are tapered surfaces, for example, these friction surfaces are flat surfaces orthogonal to the rotation axis O. Compared to a certain case, both friction surfaces can be pressed against each other with a larger surface pressure, and the friction torque during friction sliding can be increased.

(5) The first friction member 111 is axially movable and non-rotatable with respect to the main body 110, and is pressed against the second friction member 17 by the elastic body 113. When the locked portion 56 is locked and the meshing member 14 is in the second position, the friction torque can be appropriately generated between the first friction member 111 and the second friction member 17. As a result, the first rotating member 11 and the second rotating member 12 can be appropriately rotated and synchronized.

(6) Since the lubricating oil L is stored in the storage portion 7 in the disconnected state of the first rotating member 11 and the second rotating member, the first friction surface 111d of the first friction portion 111b and the second friction portion 172 Lubricating oil L interposed between the second friction surfaces 172a is reduced, and drag torque due to the viscosity of the lubricating oil L is reduced. Moreover, since the lubricating oil L stored in the storage part 7 is discharged in the connected state, each part of the driving force transmission device 1 is sufficiently lubricated.

  As mentioned above, although demonstrated based on embodiment of this invention, this invention is not limited to this embodiment, It is possible to implement in a various aspect in the range which does not deviate from the summary.

  For example, in the above-described embodiment, the case where the position of the second friction member 17 in the non-connected state is positioned at three different stages according to the temperature of the lubricating oil L has been described. It may be more than 4 stages.

DESCRIPTION OF SYMBOLS 1 ... Driving force transmission device, 1A ... Positioning mechanism, 2 ... Driving force transmission control device, 3 ... Electromagnetic coil, 4 ... Armature, 4a ... Through-hole, 4b ... Pin insertion hole, 5 ... Cam member, 5a ... Base end surface, DESCRIPTION OF SYMBOLS 6 ... Rolling bearing, 7 ... Storage part, 9 ... Control apparatus, 10 ... Housing, 11 ... 1st rotation member, 12 ... 2nd rotation member, 14 ... Meshing member, 14a ... Housing hole, 14b ... Pressed surface, 15 ... Biasing member, 16 ... receiving member, 17 ... second friction member, 19 ... locking portion, 19a ... tip surface, 19b ... side surface, 20 ... propeller shaft, 21 ... front differential, 22 ... rear differential, 23 ... drive Force interrupter, 24L, 24R ... axle shaft, 26 ... front wheel side gear mechanism, 27 ... rear wheel side gear mechanism, 28 ... torque coupling, 30 ... yoke, 30a ... hole, 31 ... bobbin, 32 Winding, 40 ... main body, 41 ... pressing protrusion, 41a ... facing surface, 41b ... side surface, 51-56 ... first to sixth locked portions, 51a-56a ... axial end surface, 51b, 52b ... side surface, 57: Wall portion, 57a: End surface, 57b: Side surface, 70: Opening / closing mechanism, 81, 82, 83 ... Ball bearing, 71 ... Body portion, 72 ... Lid portion, 91 ... Storage portion, 92 ... Control portion, 93 ... Current Output circuit, 100a ... outer peripheral spline fitting portion, 100b ... snap ring, 100c ... seal member, 100R, 100L ... ASKUL shaft, 101 ... first housing member, 102 ... second housing member, 101a ... guide portion, 102a ... opening , 102b ... hole, 102c ... receiving part, 102d ... through hole, 103 ... bolt, 110 ... main body part, 110a ... shaft part, 110b ... projecting part, 110c ... other end small diameter part, 110 ... Spline fitting part, 110e ... collar part, 110f ... spline fitting part, 110g ... outer peripheral surface, 111 ... first friction member, 111a ... flange part, 111b ... first friction part, 111c ... spline fitting part, 111d DESCRIPTION OF SYMBOLS 1st friction surface, 112 ... Holding member, 113 ... Elastic body, 113a ... Disc spring, 120 ... Cylindrical part, 120a ... Large diameter part, 120b ... One end small diameter part, 120c ... Other end small diameter part, 121 ... Outer periphery spline fitting Joint part 122 ... Inner peripheral spline fitting part 141 ... Inner cylinder part 141a ... Spline fitting part 142 ... Outer cylinder part 142a ... Spline fitting part 142b ... Outer peripheral surface 143 ... Bottom part 143a ... Spring Housing hole, 171 ... flange portion, 171a ... spline fitting portion, 172 ... second friction member, 172a ... second friction surface, 300 ... pin, 301 ... disc spring, 200 ... Four-wheel drive vehicle, 201: Driving force transmission system, 201A ... Front wheel side driving force transmission system, 201B ... Rear wheel side driving force transmission system, 202 ... Engine, 203 ... Transmission, 204L, 204R ... Front wheel, 205L, 205R ... Rear Wheels 211L, 211R ... side gears 212, 222 ... pinion gears, 213, 223 ... gear support members, 214 ... front differential case, 221L, 221R ... side gears, 224 ... rear differential case, 231 ... first spline teeth, 232 ... first 2 spline teeth portion, 233... Sleeve, 261, 271... Drive pinion, 262, 272. Support shaft

Claims (5)

A driving force transmission control device capable of switching between a connected state and a non-connected state in which the first rotating member and the second rotating member are connected so as to transmit torque.
A second engagement portion that meshes with a first engagement portion provided on the first rotation member, and a second friction portion that frictionally slides on a first friction portion provided on the first rotation member. A moving member connected to the rotating member so as to be axially movable and relatively non-rotatable;
A housing containing at least a part of the first rotating member and the second rotating member, and the moving member, and encapsulating a lubricating oil interposed between the first friction portion and the second friction portion;
An electromagnetic coil that is held in the yoke and generates a magnetic force when energized;
A control unit for controlling energization to the electromagnetic coil;
An armature that moves axially toward the yoke by the magnetic force;
A positioning mechanism capable of positioning the moving member at a plurality of positions in the axial direction in response to the axial movement of the armature;
The positioning mechanism includes a first position where the first engagement portion and the second engagement portion are engaged, a second position where the first friction portion and the second friction portion slide, and the first position. The movable member can be positioned at a plurality of positions between the second positions;
The control unit positions the moving member so that the distance between the first friction part and the second friction part in the non-connected state is increased as the temperature of the lubricating oil is lower.
Driving force transmission control device. The positioning mechanism includes a locking portion provided in the housing and a cylindrical cam member formed with a plurality of locked portions that are locked to the locking portion at different positions in the axial direction. The locking portion is configured to lock another locked portion having a different axial position among the plurality of locked portions in response to the axial movement of the armature,
The moving member moves in the axial direction together with the cam member;
The driving force transmission control device according to claim 1. The first friction surface formed on the first friction portion and the second friction surface formed on the second friction portion are tapered surfaces inclined with respect to the axial direction so as to be parallel to each other.
The driving force transmission control device according to claim 1. The first rotating member includes a shaft-shaped main body, and a friction member connected to the main body so as to be axially movable and relatively non-rotatable and having the first friction portion,
The friction member is pressed against the second friction part side by the elastic force of an elastic body, and frictionally slides with the second friction part.
The driving force transmission control device according to any one of claims 1 to 3. The housing is accommodated in the non-connected state to store a part of the lubricating oil to reduce the lubricating oil interposed between the first friction portion and the second friction portion, and in the connected state, the A storage section for discharging the stored lubricating oil;
The driving force transmission control device according to any one of claims 1 to 4.

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