JP2008095711A - Differential gear mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein a conventional differential locking mechanism makes a large operation force and a large operation stroke necessary to engage an engaging member such as a pin and a dog for the differential locking, with differential side gears, etc., and as a result, turns an operating load on an operator heavier, and further may deform an operation element for transmitting the operation force to the engaging member by an excessive load. <P>SOLUTION: A differential gear mechanism comprises a differential locking mechanism 13 in which, a clutch member 103 is provided so as to be connected to an input member 30 and so as to engage with the differential side gears 33, and the clutch member 103 is engaged with the differential side gears 33 side by being pushed by the relative rotation between the clutch member 103 and the input member 30, and the torque of the input member 30 is transmitted from the clutch member 103 to axle shafts 7 via the differential side gears 33. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention includes an input member such as a diff ring gear for inputting power for driving an axle, a pinion pivotally supported by the input member, and a differential side gear that meshes with the pinion and is fixed on the axle. More particularly, the present invention relates to a diff lock mechanism for improving the straightness and the runnability in a muddy state.

In a conventional differential lock mechanism, a differential lock pin is provided on a differential lock slider that is spline-fitted to a boss portion of a differential case, and the differential lock pin is a pin that is drilled in a differential side gear fixed to an axle by sliding operation of the differential lock slider. A technique for diff-locking by engaging with a hole is known (see, for example, Patent Document 1).
JP 52-66235 A

  However, in order to engage the engagement member such as the differential lock pin and the dog with the differential side gear or the like in this way, a large operation force or operation stroke is required, so that the operation burden on the operator is heavy, and the engagement member There is a problem that the operation fitting for transmitting the operation force may be deformed due to excessive load.

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.
In other words, the present invention comprises an input member that inputs power for driving the axle, a pinion that pivotally supports the input member, and a differential side gear that meshes with the pinion and is fixed on the axle. In the differential gear device, a clutch member that is connected to the input member and engageable with the differential side gear is provided, and the clutch member is pushed toward the differential side gear by relative rotation between the clutch member and the input member. And a differential lock mechanism that transmits the torque of the input member from the clutch member to the axle via the differential side gear.
According to a second aspect of the present invention, the differential lock mechanism includes a cam mechanism on a surface where the clutch member and the input member face each other, and the clutch member and the input member are connected via the cam mechanism.
According to a third aspect of the present invention, the differential lock mechanism includes an extrusion member provided in the clutch member, a differential lock slider that pushes and pulls the extrusion member toward the differential side gear to switch between differential lock and unlock, and sliding operation of the differential lock slider An operation fitting is provided, and a configuration is provided between the push-out member and the diff lock slider so that an operation force from the operation fitting can be stored during the diff lock.
According to a fourth aspect of the present invention, a structure is provided between the push-out member and the differential lock slider so that the operation force from the operation fitting can be directly transmitted to the push-out member when unlocked.
According to a fifth aspect of the present invention, the differential lock mechanism is provided with an actuator for operating the operation fitting.

Since this invention was comprised as mentioned above, there exists an effect shown below.
In other words, the present invention comprises an input member that inputs power for driving the axle, a pinion that pivotally supports the input member, and a differential side gear that meshes with the pinion and is fixed on the axle. In the differential gear device, a clutch member that is connected to the input member and engageable with the differential side gear is provided, and the clutch member is pushed toward the differential side gear by relative rotation between the clutch member and the input member. And a differential lock mechanism that transmits the torque of the input member from the clutch member to the axle via the differential side gear, so that the clutch member is pushed by a predetermined stroke at the time of differential lock (hereinafter referred to as “initial push operation”). The clutch member is only partially engaged with the differential side gear (hereinafter referred to as “partial engagement”). By rotating the clutch member and the input member relative to each other in opposite directions, the clutch member can be automatically engaged with the differential side gear to the end, and the operation force and operation stroke required for the differential lock operation can be reduced. , The operator's operational burden is reduced. Furthermore, a large load does not act on the operation fitting for the diff lock operation, the deformation and breakage thereof can be prevented, and the time required for maintenance can be shortened and the cost can be reduced.
According to a second aspect of the present invention, the differential lock mechanism has a cam mechanism on a surface facing the clutch member and the input member, and the clutch member and the input member are connected via the cam mechanism. When the clutch member is partially engaged with the differential side gear by performing a pushing operation, the clutch member is rotated relative to the input member by the differential side gear, and the positions of the opposing surfaces are greatly displaced in the rotation direction. The cam part runs on the shallow part. As a result, the clutch member can be pushed toward the differential side gear and can be reliably engaged to the end by the horizontal component force of the drag received from the cam portion. In addition, such an effect can be achieved with a simple configuration, and parts and structures necessary for the diff lock mechanism can be simplified, thereby reducing manufacturing costs and improving maintainability.
According to a third aspect of the present invention, the differential lock mechanism includes an extrusion member provided in the clutch member, a differential lock slider that pushes and pulls the extrusion member toward the differential side gear to switch between differential lock and unlock, and sliding operation of the differential lock slider Since a structure is provided between the push-out member and the diff lock slider so that the operation force from the operation fitting can be stored when the diff lock is applied, the clutch member is attached after the initial pushing operation during the diff lock. Even when the differential side gear is not partly engaged, the clutch member can be held in a state of being biased toward the differential side gear, and it is not necessary to repeat the diff lock operation with the operating bracket many times. Therefore, the differential engagement can be achieved by partial engagement in a short time. Furthermore, a large load does not directly act on the operation fitting, and the deformation and breakage thereof can be prevented, and the time required for maintenance of the differential lock mechanism can be shortened and the cost can be reduced.
According to a fourth aspect of the present invention, a structure is provided between the push-out member and the diff-lock slider so that the operation force from the operation fitting can be directly transmitted to the push-out member when unlocked. Even when in a state of being strongly engaged, it is possible to quickly release the engagement between the clutch member and the differential side gear by reliably pulling out the pushing member via the differential lock slider by the unlocking operation using the operation fitting. Unlocking can be performed quickly and reliably.
In claim 5, since the actuator for operating the operation fitting is provided in the differential lock mechanism, the switching operation of the differential lock and the unlock can be performed by a simple switching operation, and the operation burden on the operator is reduced. In addition, the switching operation is accelerated, and a quick response according to the situation of the vehicle becomes possible.

Next, embodiments of the invention will be described.
FIG. 1 is a skeleton diagram showing a power transmission configuration of an axle drive unit equipped with a differential gear device according to the present invention, FIG. 2 is a partial front sectional view of a differential lock mechanism according to the present invention, and FIG. 4 is a partial front sectional view showing the structure around the clutch member when unlocked, FIG. 5 is a partial front sectional view showing the structure around the clutch member in a partially engaged state during diff lock, and FIG. It is a fragmentary front sectional view which shows the clutch member peripheral structure in the engaged state.

First, the overall configuration of the axle drive unit 1 equipped with the differential gear device 12 according to the present invention will be described with reference to FIG.
An axle drive unit 1 disposed in a vehicle body 5 includes an engine 2 that is a prime mover, an axle drive device 4 that supports and drives axles 7 and 7 to which left and right wheels 6 and 6 are fixed, and the axle. The main transmission device 3 is configured to connect the drive device 4 and the engine 2 and shift and transmit the power from the engine 2 to the axle drive device 4.

  Of these, the axle drive device 4 includes a transmission 10 which is a device for shifting the power from the engine 2, and is accommodated together with the axles 7, 7, and an input shaft 9 of the transmission 10 and an output shaft 8 from the engine 2. Are connected by the main transmission 3.

  The housing 11 of the axle drive device 4 is formed by joining the left and right housing halves, and the pair of left and right axles 7 and 7 and the axles 7 and 7 are differentially connected to the inner compartment. A differential gear device 12 having a differential lock mechanism 13 according to the present invention for coupling, a centrifugal governor 14 disposed on the input shaft 9, and a sub-shift that performs a sub-shift in conjunction with an operation of a sub-shift lever (not shown). A transmission mechanism 15 and the like are disposed. Further, a power take-out portion 16 for outputting power to another axle drive device or the like is provided on the side portion of the axle drive device 4.

  Among these, the centrifugal governor 14 is attached to the input shaft 9 and rotated outward according to the centrifugal force to detect a rotational speed of the input shaft 9, and an outer side of the governor weight 17. The lifter 18 is moved in the axial direction in conjunction with the rotation of the engine 2, and the lifter 18 is connected to a throttle valve of the engine 2 and an appropriate one via an unillustrated governor fork, governor shaft, and output arm. They are linked by a link mechanism. Thus, the centrifugal governor 14 detects the rotational speed of the input shaft 9 and adjusts the fuel injection amount of the engine 2 accordingly, and the power of the engine 2 is increased as the rotational speed of the input shaft 9 increases or decreases. The output can be changed.

  In the auxiliary transmission mechanism 15, the input shaft 9 constitutes a driving side, and a high speed gear 19 is fixed to the input shaft 9 so as not to be relatively rotatable, and a low speed gear 20 and a reverse gear 21 are provided. It is engraved integrally. Further, a transmission shaft 22 is arranged in parallel with the input shaft 9, and a high speed driven gear 23 and a reverse driven gear 25 are loosely fitted to the transmission shaft 22 so as to be relatively rotatable. A low-speed driven gear 24 is provided on the boss portion so as to be relatively rotatable. Of these, the high-speed driven gear 23 is engaged with the high-speed gear 19, the low-speed driven gear 24 is engaged with the low-speed gear 20, and the reverse driven gear 25 is provided in the housing 11 so as to be freely rotatable. The reverse gear 21 is meshed with a reverse gear (not shown).

  A spline hub 26 is mounted between the low-speed driven gear 24 and the reverse driven gear 25 on the transmission shaft 22 so as not to be relatively rotatable. On the spline hub 26, the clutch slider 27 is relatively non-rotatable. The clutch slider 27 is slidably displaced in the axial direction, so that the clutch slider 27 is moved to any one of the high-speed driven gear 23, the low-speed driven gear 24, and the reverse driven gear 25. Engagement is made so that forward rotation at high speed, low speed rotation, or reverse rotation can be selectively applied to the transmission shaft 22. Alternatively, the clutch slider 27 can be set to a neutral position where it does not engage any of the high speed driven gear 23, the low speed driven gear 24, and the reverse driven gear 25. Further, the clutch slider 27 is linked to an auxiliary transmission lever (not shown) via a clutch fork shaft configured to be slidable linearly. Thus, the clutch slider 27 can be set to the low speed forward position, the high speed forward position, the reverse position, or the neutral position by the tilting operation of the auxiliary transmission lever.

  The power thus sub-shifted is differentially transmitted to the pair of left and right axles 7 and 7 via a differential gear device 12 to be described later, and a frictional disc brake is placed on the axles 7 and 7. Devices 37 and 37 are provided, respectively, so that a braking force by a foot brake can be applied to the axles 7 and 7 by operating a brake pedal (not shown).

  In the power take-out portion 16, one end of the transmission shaft 22 extends to the left and right sides of the body of the housing 11, and a transmission shaft 40 is connected to the extended portion via a coupling 39. The tip of 40 extends further to the same side and protrudes outward from the side surface of the housing 11. The transmission shaft 40 protrudes into a drive take-out case 38 that is provided in a convex shape on the side surface of the axle drive device 4, and a bevel gear 41 is fixed to the tip of the protruding portion. A bevel gear 43 is also fixed to the output shaft 42 supported in the longitudinal direction of the machine body, and the bevel gear 43 is engaged with the bevel gear 41. The output shaft 42 projects forward from the drive take-out case 38 and is connected to an input shaft of another axle drive device or the like via a drive shaft 44. As a result, the power after shifting can be transmitted from the power take-out unit 16 to another axle drive device or the like, so that it is possible to cope with four-wheel drive or multi-wheel drive of six or more wheels.

  The main transmission 3 that connects the axle driving device 4 having such a configuration to the engine 2 is a belt-type continuously variable transmission, and power that transmits power from the engine 2 to the transmission 10. A transmission train 45 and a braking force transmission train 46 arranged side by side on the power transmission train 45 are configured.

  In the power transmission train 45, the drive-side pitch diameter varying device 51 is housed in the first case 49, and when the rotational speed of the output shaft 8 increases in the drive-side pitch diameter varying device 51, the output shaft The movable pulley 47b of the V drive pulley 47 is pushed toward the fixed pulley 47a by a weight or the like provided in the motor 8, and the power from the output shaft 8 is transmitted to the V drive pulley 47 (hereinafter referred to as “power”). In the "connected state"), the interval between the fixed pulley 47a and the movable pulley 47b is narrowed, the pitch diameter of the V drive pulley 47 is increased, and a high speed stage with a small reduction ratio is obtained. On the contrary, when the rotational speed of the output shaft 8 decreases, the distance between the fixed pulley 47a and the movable pulley 47b increases, and the pitch diameter of the V drive pulley 47 decreases, resulting in a low speed stage with a large reduction ratio. . When the rotational speed of the output shaft 8 further decreases and the movable pulley 47b moves away from the fixed pulley 47a by a certain distance or more, the movable pulley 47b is completely separated from the V belt 54, and the rotational force of the output shaft 8 is increased by the V belt. No power is transmitted to 54 (hereinafter referred to as “power cut-off state”), thereby forming a power connection / disconnection structure.

  On the other hand, a V driven pulley 48 is provided at the left end of the input shaft 9, and a driven side pitch diameter variable device housed in a second case 52 is placed on the input shaft 9 on the right side of the V driven pulley 48. 53, and in the driven side pitch diameter varying device 53, the movable pulley 48b of the V driven pulley 48 is always urged by a spring or the like toward the fixed pulley 48a. A V belt 54 is wound between the V drive pulley 47 and the V driven pulley 48. Power from the engine 2 is transmitted from the output shaft 8 to the V drive pulley 47, the V belt 54, and the V driven. After being shifted through the pulley 48, it is transmitted from the input shaft 9 into the transmission 10.

  In the braking force transmission train 46, the right end of the drive pulley shaft 58 is fastened to the left end of the output shaft 8, and a toothed drive pulley 55 is fastened to the drive pulley shaft 58. On the other hand, a left end portion of a driven pulley shaft 59 is rotatably supported by a bearing 62 fixed to the vehicle body 5 or a device cover (not shown), and a toothed driven pulley is attached to the right portion of the driven pulley shaft 59. 56 is fitted and fixed, and a toothed belt 57 is wound between the toothed driven pulley 56 and the toothed drive pulley 55, and the driven pulley shaft 59 is always connected to the output shaft 8. It has become.

  A one-way clutch 65 is interposed between the right end of the driven pulley shaft 59 and the clutch shaft 64 fastened to the fixed pulley 48a. In the one-way clutch 65, the clutch shaft 64 is arranged around the clutch shaft 64. The housing 65a of the one-way clutch 65 is fitted so as to be rotatable only in one direction (hereinafter referred to as “idling direction”) via the clutch element 65b, and the housing 65a is attached to the right end of the driven pulley shaft 59. It is connected. In such a one-way clutch 65, the rotational direction of the clutch shaft 64 connected to the input shaft 9 of the transmission 10 and the rotational direction of the driven pulley shaft 59 connected to the output shaft 8 from the engine 2 are both described above. If the rotational speed of the clutch shaft 64 is equal to or less than the rotational speed of the driven pulley shaft 59, the housing 65a connected to the driven pulley shaft 59 rotates relative to the clutch shaft 64 in the idle direction. Then, the clutch shaft 64 can be idled or rotated. On the other hand, when the rotational speed of the clutch shaft 64 exceeds the rotational speed of the driven pulley shaft 59, the housing 65a rotates relative to the clutch shaft 64 in the direction opposite to the idling direction and becomes unable to rotate relative to the clutch shaft 64. The one-way clutch 65 is engaged, and the driven pulley shaft 59 and the clutch shaft 64 are connected.

  In such a configuration, when the rotational speed of the engine 2 increases, a power connection state is established, the V drive pulley 47 is connected to the output shaft 8, and the distance between the fixed pulley 47a and the movable pulley 47b is increased. As a result, the pitch diameter of the V drive pulley 47 increases and the power from the output shaft 8 is shifted from the input shaft 9 to the transmission at a high speed with a small reduction ratio by the power transmission train 45. 10 is transmitted.

  As the engine 2 is decelerated, the distance between the fixed pulley 47a and the movable pulley 47b increases, and the pitch diameter of the V drive pulley 47 decreases, and the power from the output shaft 8 is transmitted to the power transmission. After being shifted to low speed gear having a large reduction ratio by the train 45, it is transmitted from the input shaft 9 into the transmission 10.

  Further, when the engine 2 is decelerated and the rotation speed of the output shaft 8 falls below a predetermined limit speed, the power is cut off and the output shaft 8 and the V-belt 54 are cut off, and the engine 2 is also idling. Thus, the power from the V drive pulley 47 is not transmitted to the V driven pulley 48. For this reason, the V driven pulley 48 can freely rotate. However, when the rotational speed of the V driven pulley 48 increases and the rotational speed of the clutch shaft 64 exceeds the rotational speed of the driven pulley shaft 59, as described above, The housing 65a rotates relative to the clutch shaft 64 in the direction opposite to the idling direction and cannot rotate relative to the clutch shaft 64. The one-way clutch 65 is in the "on" state, the driven pulley shaft 59 and the clutch shaft 64 are connected, and the engine 2 Braking force, so-called engine brake, acts on the input shaft 9 of the transmission 10 via the braking force transmission train 46. This minimizes the use of foot brakes when trying to go down a long downhill in an idling state, avoids the occurrence of fade and vapor lock phenomena due to frictional heat, and ensures stable braking performance It can be done.

Next, the differential gear device 12 provided in the axle drive device 4 will be described with reference to FIGS.
As shown in FIGS. 1 and 2, the rotation of the transmission shaft 22 is transmitted to the differential gear device 12 through an output gear 28 fixed to a portion near one end of the transmission shaft 22. It is configured. That is, the differential gear device 12 has a hollow differential case 29 supported in the axle drive device 4 so as to have the same rotational axis as the axles 7 and 7, and is fastened and fixed to the outer peripheral surface of the differential case 29 by the bolt 100. A ring gear 30 that meshes with the output gear 28 of the transmission shaft 22, a pinion shaft 31 that is disposed orthogonally to the axles 7 and 7 in the differential case 29 and rotates integrally with the differential case 29, and rotates at both ends of the pinion shaft 31. Pinions 32 and 32, which are freely bevel gears, and differential side gears 33 and 33, which are bevel gears fixed to the inner ends of the axles 7 and 7 and meshed with the pinions 32 and 32, are configured. As a result, the rotation input to the ring gear 30 from the transmission shaft 22 via the output gear 28 is transmitted to the axles 7 and 7 as a differential rotation. A differential lock mechanism 13 for locking the differential rotation is provided.

  As shown in FIGS. 1 to 4, in the differential lock mechanism 13, a differential side gear 33 is spline-fitted to the inner end of the axle 7 and fixed by a cylindrical fixing member 117, and a clutch is mounted on the fixing member 117. A member 103 is slidably fitted in both the axial direction and the circumferential direction, and a lock pin 102 projects in the axial direction from the outer surface of the clutch member 103. The lock pin 102 is inserted into elongated operation holes 30c, 30c, and 30c formed in the main body 30b so as to be in contact with the base of the boss 30a of the ring gear 30. The first half portion is slidably fitted into a pin hole 101a of a differential lock slider 101 that is externally fitted to the boss portion 30a so as to be slidable in the axial direction.

  Further, a ring-shaped stopper 102a is formed at the tip of the lock pin 102 so that even if the differential lock slider 101 slides outward, it is locked by the lock pin 102 so as not to fall off. . On the other hand, a spring 104 is externally fitted to the lock pin 102 between the differential lock slider 101 and the clutch member 103. When the differential lock slider 101 slides in the direction of the arrow 113, the spring 104 is compressed and generated. The clutch member 103 is pushed toward the differential side gear 33 by the urging force.

  A plurality of clutch claws 33a are formed on the clutch member 103 side by the differential side gear 33, and a plurality of clutch claws 103a are formed on the differential side gear 33 side by the clutch member 103 so as to be fitted to the clutch claws 33a. Has been. A spring 105 is interposed in a compressed state between the spring receiver 103b of the clutch member 103 and the spring receiver 29a of the differential case 29, and is biased so that the differential side gear 33 and the clutch member 103 are separated from each other. Normally, the clutch pawl 33a and the clutch pawl 103a cannot be fitted.

  Further, a cam mechanism having the following configuration is provided between the clutch member 103 and the ring gear 30. That is, on the ring gear 30 side of the clutch member 103, a saddle-like recess formed by forming a shallowest portion at both ends of the deepest portion at the center and continuously shallowing along the circumferential direction. 103c is formed, facing the flange-shaped recess 103c, and on the clutch member 103 side of the ring gear 30, as in the case of the flange-shaped recess 103c, the central deepest portion and the circumferential direction are continuous with this. The bowl-shaped recesses 30d are formed with the shallowest portions formed at both ends of the bowl-shaped recesses 30d. The ball members 106 are inserted so as to straddle the bowl-shaped recesses 103c and the bowl-shaped recesses 30d. Is retained. If the ball member 106 is used as in the present embodiment, the frictional resistance can be reduced, but a projection or the like may be used simply, and the configuration of this cam mechanism is not particularly limited.

  The differential lock slider 101 is engaged with a tip portion of a fork-shaped operation fitting 108, and a boss portion 108 a at the base of the operation fitting 108 is externally fitted to and suspended from the fork shaft 109. The fork shaft 109 is slidably supported with respect to the housing 11, and an actuator 107, which is a push-pull type electric actuator, is disposed on one side of the housing 11. The fork shaft 109 is disposed on one side end on substantially the same axis.

  In the actuator 107, a motor 107b is provided at an outer end of the case 107a, and an output shaft of the motor 107b is connected to a screw shaft 107d via a planetary gear type speed increasing device 107c, and the screw shaft 107d. The nut 107e that is screwed onto the piston 107f is locked so as not to rotate relative to the piston 107f and to prevent axial sliding. When the motor 107b is operated by a controller (not shown), the rotational output of the screw shaft 107d rotates at a high speed via the speed increasing device 107c, and the screw shaft 107d and the nut 107e convert the rotational motion into a linear motion. The piston 107f in contact with one end of the fork shaft 109 can be slid back and forth in the axial direction.

  Further, on the fork shaft 109, retaining rings 110a and 110b and a sliding wheel 110c are fitted in order from the right, and a spring 111 and an operation between the fixed retaining ring 110a and the retaining ring 110b are fixed. The boss portion 108a of the metal fitting 108 is disposed in order from the right, and a spring 112 is disposed between the fixed retaining ring 110b and the slidable sliding ring 110c, and both springs 111 and 112 are interposed in a compressed state. It is installed.

  In such a configuration, as shown in FIGS. 2 and 4, when a diff lock signal is transmitted from the controller to the actuator 107 by operating a switch (not shown) at the time of diff lock, the motor 107 is activated and moves in the direction of the arrow 113. The piston 107f slides, the fork shaft 109 is pushed by the piston 107f, and the operation fitting 108 is urged through the spring 111 by the retaining ring 110a fitted to the fork shaft 109 in the state of the arrow 113. Pushed in the direction.

  Then, as shown in FIG. 5, the differential lock slider 101 slides on the lock pin 102 and compresses the spring 104, and the urging force of the spring 104 generated by this compression is generated between the differential case 29 and the clutch member 103. The clutch member 103 is pushed toward the differential side gear 33 side against the biasing force of the spring 105 to perform an initial pushing operation, and further, the clutch member 103 is moved toward the differential side gear 33 side by the biasing force of the spring 104. In the biased state, it can be held until it is partially engaged.

  That is, the differential lock mechanism 13 includes a lock pin 102 that is an extrusion member provided in the clutch member 103, a differential lock slider 101 that switches between differential lock and unlock by pushing and pulling the lock pin 102 toward the differential side gear 33 side, An operation fitting 108 for slidingly operating the diff lock slider 101 is provided, and a spring 104 is configured between the lock pin 102 and the diff lock slider 101 so that an operation force from the operation fitting 108 can be stored during the diff lock. Therefore, even when the clutch member 103 is not partly engaged with the differential side gear 33 after the initial pushing operation, the clutch member 103 is held in a state of being biased toward the differential side gear 33 at the time of differential lock. The differential lock operation by the operation fitting 108 can be performed many times. Rather than repeating, differential lock is possible partial engagement in a short period of time increases the probability that engages. Further, a large load does not directly act on the operation fitting 108, and the deformation and breakage thereof can be prevented, and the time required for maintenance of the differential lock mechanism 13 can be shortened and the cost can be reduced. . These effects are further enhanced by a spring 111 provided on the fork shaft 109.

  When the clutch pawl 103a of the clutch member 103 is partially engaged with the clutch pawl 33a of the differential side gear 33 by the initial pushing operation as described above, the clutch member 103 is rotated in the direction of the arrow 115 by the clutch pawl 33a. As a result, relative rotation occurs in the opposite direction between the clutch member 103 and the ring gear 30, and the opposed saddle-shaped recesses 103c and 30d are also greatly displaced in the rotation direction. Accordingly, the ball member 106 rolls in a space sandwiched between the bowl-shaped recesses 103c and 30d and rides on a shallow portion near the periphery of the bowl-shaped recesses 103c and 30d. The clutch member 103 is strongly pushed toward the differential side gear 33 by the horizontal component force 116 a of the drag force 116 received from the member 106. And this pushing is automatically continued by the said horizontal component force 116a until it will be in an engagement state as shown in FIG.

  That is, the differential lock mechanism 13 has a bowl-shaped recess 103c, 30d and a ball that is fitted and held between the clutch member 103 and the ring gear 30 that is an input member so as to straddle between the bowl-shaped recess 103c, 30d. The clutch mechanism and the input member are connected via the cam mechanism, so that the initial pushing operation is performed and the clutch member 103 is partially engaged with the differential side gear 33. Then, the clutch member 103 is rotated relative to the ring gear 30 by the differential side gear 33, and the positions of the opposing surfaces are greatly displaced in the rotation direction, so that the ball member 106, which is the cam portion of the cam mechanism, becomes a bowl-shaped recess. It rides on a shallow part near the periphery of 103c and 30d. As a result, the clutch member 103 can be pushed to the side of the differential side gear 33 and reliably engaged until the end by the horizontal component 116a of the drag 116 received from the ball member 106 as the cam portion. Moreover, such an effect can be achieved with a simple configuration, and parts and structure required for the diff lock mechanism 13 can be simplified, and manufacturing costs can be reduced and maintainability can be improved.

  Subsequently, at the time of unlocking, when an unlock signal is transmitted from the controller (not shown) to the actuator 107 by operating the switch, the motor 107 is activated and the piston 107f slides in the direction of the arrow 114. Then, the fork shaft 109 receives the biasing force of the spring 112 and slides in the direction of the arrow 114 until the retaining ring 110a abuts against the inner wall of the housing 11, and at the same time, the boss portion 108a of the operation fitting 108 is moved to the retaining ring 110b. Is pushed directly in the direction of arrow 114.

  Then, the differential lock slider 101 slides on the lock pin 102 and comes into contact with the stopper 102a, and the lock pin 102 is pulled out strongly in the direction of the arrow 114 to quickly release the engagement between the differential side gear 33 and the clutch member 103. be able to.

  That is, a stopper 102a is provided between the lock pin 102, which is the pushing member, and the differential lock slider 101. The stopper 102a is configured so that the operation force from the operation fitting 108 can be directly transmitted to the lock pin 102 when unlocked. Even when the clutch member 103 is strongly engaged with the differential side gear 33 at the time of locking, the lock pin 102 is reliably pulled out via the differential lock slider 101 by the unlocking operation by the operation fitting 108 and the clutch member 103 The engagement with the differential side gear 33 can be quickly released, and unlocking can be performed quickly and reliably. These effects are further enhanced by the retaining ring 110b provided on the fork shaft 109.

  As described above, the ring gear 30 that is an input member that inputs power for driving the axle 7, the pinion 32 that pivotally supports the differential case 29 that constitutes the input member together with the ring gear 30, and the pinion 32 mesh with the pinion 32. In addition, in the differential gear device 12 constituted by the differential side gear 33 fixed on the axle 7, a clutch member 103 that is connected to the ring gear 30 and engageable with the differential side gear 33 is provided, and the clutch member The clutch member 103 is pushed and engaged with the differential side gear 33 by relative rotation between the ring member 30 and the ring gear 30, and the torque of the ring gear 30 is transmitted from the clutch member 103 to the axle 7 via the differential side gear 33. Since the differential lock mechanism 13 is provided, the clutch member 103 is moved to a predetermined stroke during the differential lock. Then, the clutch member 103 is only partially engaged with the differential side gear 33, and thereafter, the clutch member 103 is automatically rotated between the clutch member 103 and the ring gear 30, so that the clutch member 103 is automatically engaged with the differential side gear 33. The operation force and operation stroke required for the differential lock operation can be reduced, and the operator's operation load is reduced. Further, a large load does not act on the operation fitting 108 for the diff lock operation, and the deformation and breakage thereof can be prevented, and the time required for maintenance and the cost can be reduced.

  Since the differential lock mechanism 13 is provided with an actuator 107 for operating the operation fitting 108, the switching operation of the differential lock and unlock can be performed by a simple switching operation, and the operation burden on the operator is reduced. As a result, the switching operation becomes faster, and a quick response according to the situation of the vehicle becomes possible.

  The present invention includes a differential lock comprising an input member for inputting power for driving an axle, a pinion pivotally supported by the input member, and a differential side gear meshing with the pinion and fixed on the axle. The present invention can be applied to various drive vehicles equipped with a differential gear device with a mechanism.

It is a skeleton figure which shows the power transmission structure of the axle shaft drive part which mounts the differential gear apparatus concerning this invention. It is a partial front sectional view of a differential lock mechanism concerning the present invention. It is an AA arrow line view of FIG. It is a fragmentary front sectional view which shows the clutch member periphery structure at the time of unlocking. It is a partial front sectional view showing a clutch member peripheral structure in a state of partial engagement at the time of differential lock. It is a fragmentary front sectional view which shows the clutch member periphery structure in the state engaged to the last at the time of differential lock | rock.

Explanation of symbols

7 Axle 12 Differential gear device 13 Differential lock mechanism 29/30 Input member 32 Pinion 33 Differential side gear 101 Differential lock slider 102 Pushing member 102a Configuration capable of directly transmitting operating force 103 Clutch member 104 Configuration capable of accumulating operating force 107 Actuator 108 Operating bracket

Claims (5)

  In the differential gear device comprising: an input member for inputting power for driving the axle; a pinion pivotally supported by the input member; and a differential side gear meshing with the pinion and fixed on the axle. A clutch member that is connected to the member and engageable with the differential side gear is provided, and the clutch member is pushed and engaged with the differential side gear by the relative rotation between the clutch member and the input member. A differential gear device comprising a differential lock mechanism for transmitting torque from a clutch member to an axle via a differential side gear.   2. The differential lock mechanism according to claim 1, wherein the differential lock mechanism has a cam mechanism on a surface where the clutch member and the input member face each other, and the clutch member and the input member are connected via the cam mechanism. Differential gear device.   The differential lock mechanism includes an extruding member provided on the clutch member, a differential lock slider that switches the differential lock and unlock by pushing and pulling the extruding member toward the differential side gear, and an operation fitting that slides the differential lock slider. The differential gear device according to claim 1, wherein a configuration is provided between the push-out member and the differential lock slider so that an operation force from the operation fitting can be accumulated during the differential lock.   The differential gear device according to claim 3, wherein a configuration is provided between the push member and the differential lock slider so that an operation force from the operation fitting can be directly transmitted to the push member when unlocked.   The differential gear device according to claim 3 or 4, wherein the differential lock mechanism is provided with an actuator for operating the operation fitting.

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