JP4531678B2 - Shaft drive type vehicle - Google Patents

Description

  The present invention relates to a shaft drive type vehicle that transmits an output from an engine to a wheel shaft via a propeller shaft and a bevel gear transmission mechanism.

Conventionally, in the above shaft drive type vehicle, the tip of the propeller shaft is spline-fitted to the bevel gear transmission mechanism, and a truncated cone-shaped protrusion is provided at the abutting portion of the tip of the propeller shaft to the bevel gear transmission mechanism. (For example, refer to Patent Document 1).
JP 2002-283863 A (FIGS. 3 and 10)

By the way, in the above-mentioned conventional configuration, since the projection that hits the bevel gear transmission mechanism is a truncated cone, the contact area between the projection and the bevel gear transmission mechanism is likely to be large, and consideration is given to lubrication between them. At the same time, consideration must be given to the vibration absorption of the propeller shaft.
Accordingly, the present invention provides a shaft drive type vehicle that facilitates lubrication between the propeller shaft and the bevel gear transmission mechanism and that can well absorb the vibration of the propeller shaft.

As a means for solving the above-mentioned problems, the invention described in claim 1 is characterized in that the propeller shaft (for example, the front propeller shaft 6 of the embodiment) for transmitting the output from the engine (for example, the engine 5 of the embodiment) is connected to the propeller shaft. And a bevel gear transmission mechanism (for example, the bevel gear transmission mechanisms 16, 116, 216, 316 of the embodiment) that transmits the power transmitted from the propeller shaft to the wheel shaft (for example, the front drive shaft 11 of the embodiment). In a shaft drive type vehicle (for example, the shaft drive type vehicle 1 of the embodiment), the abutment portion (for example, the front end portion 6a, the bottom portion 32a, the shaft portion 237 of the embodiment) with one of the propeller shaft and the bevel gear transmission mechanism. 238), a conical protrusion (for example, the protrusions 68, 168, 268, 368 of the embodiment) that contacts the other. Provided, said bevel gear transmission mechanism, said a joint (joint 126 of example embodiment) in which the propeller shaft is connected, the bevel gear shaft for transmitting the power of the propeller shaft which is transmitted from the joint to the wheel shaft (e.g. The bevel gear shaft 127) of the embodiment, and a housing (for example, the housing 28 of the embodiment) that accommodates the joint and the bevel gear shaft and supports them via outer bearings (for example, the front and rear ball bearings 35, 44 of the embodiment). The joint is formed in a hollow shape, and the shaft portion (for example, the shaft portion 337 of the embodiment) of the bevel gear shaft passes through the hollow portion (for example, the front portion 131 of the embodiment) and the shaft portion. Is supported by the hollow portion, and the projection (for example, the projection 368 of the embodiment) is formed at the tip of the shaft portion .
A shaft drive comprising: a propeller shaft that transmits an output from an engine; and a bevel gear transmission mechanism that is connected to the propeller shaft and transmits power transmitted from the propeller shaft to a wheel shaft. In the type vehicle, a conical protrusion that abuts the other of the propeller shaft and the bevel gear transmission mechanism on the other is provided, and the bevel gear transmission mechanism is a joint to which the propeller shaft is connected. (For example, the joint 26 of the embodiment), a bevel gear shaft (for example, the bevel gear shaft 27 of the embodiment) that transmits the power of the propeller shaft transmitted from the joint to the wheel shaft, and the joint and the bevel gear shaft. The clutch mechanism (for example, in the embodiment) A latch mechanism (18) and a housing (for example, a housing that accommodates the joint, the bevel gear shaft, and the clutch mechanism, and supports the joint and the bevel gear shaft via outer bearings (for example, the front and rear ball bearings 35 and 44 in the embodiment) And the joint is formed in a hollow shape, and the shaft portion of the bevel gear shaft (for example, the shaft portion 237 of the embodiment) passes through the hollow portion (for example, the front portion 31 of the embodiment). In addition, the shaft portion is supported in the hollow portion via an inner bearing (for example, front and rear needle bearings 239a and 239b), and the protrusion (for example, the protrusion 268 of the embodiment) is formed at the tip of the shaft portion. It is characterized by being

The invention described in claim 3 is characterized in that the protrusion is provided on an axis of the propeller shaft (for example, the axis Y of the embodiment).

According to a fourth aspect of the present invention, the propeller shaft and the bevel gear transmission mechanism are spline-connected, and a spherical spline is formed at one of these connecting portions (for example, the yoke portion 32 and the front end portion 6a in the embodiment). It is characterized by being.

According to the present invention , since the projection that strikes the other of the propeller shaft and the bevel gear transmission mechanism is conical, the contact area between the projection and the other is reduced, and therefore the lubrication between them Can be easily performed. In addition, since the propeller shaft and the bevel gear transmission mechanism are relatively easily oscillated, the propeller shaft can be well absorbed and power can be transmitted smoothly.

According to the present invention , the vibration of the propeller shaft can be absorbed even better.

According to the present invention , the shaft portion of the bevel gear shaft is supported by the hollow portion of the joint, so that the increase in the size of the outer bearing and the increase in the size of the bevel gear transmission mechanism is suppressed, and the meshing reaction force of the bevel gear is received. It is possible to stably support the bevel gear shaft by increasing the number of supporting portions.

According to the present invention , the shaft portion of the bevel gear shaft is supported by the hollow portion of the joint, so that the increase in the size of the outer bearing and the increase in the size of the bevel gear transmission mechanism is suppressed, and the meshing reaction force of the bevel gear is received. It is possible to stably support the bevel gear shaft by increasing the number of supporting portions. In addition, since the support of the bevel gear shaft is improved, it is possible to smoothly switch between power transmission and cutting by the clutch mechanism.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the directions such as front, rear, left and right are the same as those in the vehicle unless otherwise specified. In the figure, the arrow FR indicates the front of the vehicle, the arrow LH indicates the left side of the vehicle, and the arrow UP indicates the upper side of the vehicle.

  A shaft drive type vehicle 1 shown in FIG. 1 includes left and right front wheels 2 and rear wheels 3 which are relatively large-diameter low-pressure balloon tires in front of and behind a small and lightweight vehicle body to ensure a large minimum ground clearance. In particular, it is configured as a so-called ATV (All Terrain Vehicle) with improved running performance on rough terrain. The vehicle body frame 4 of the shaft drive type vehicle 1 forms a box structure that is long in the front-rear direction in the center portion in the vehicle width direction. Is done.

  Referring also to FIG. 2, the engine 5 is, for example, a water-cooled single cylinder engine, and has a vertical layout in which the rotation shaft of the crankshaft is aligned in the vehicle front-rear direction. Front and rear propeller shafts 6 and 7 for power transmission are led out from the lower part of the engine 5 toward the front and rear, respectively, and the front ends of the propeller shafts 6 and 7 are located below the front part of the vehicle body frame 4 or below the rear part. On the side, it is connected to the front reduction gear 8 or the rear reduction gear 9. The rotational driving force of each propeller shaft 6, 7 input to each reduction gear 8, 9 is converted into the rotational driving force of the left / right front drive shaft 11 or the left / right rear drive shaft 12 as the wheel axis, and the left / right front wheels 2 or rear Output to wheel 3.

  The left and right front wheels 2 are configured to be steerable via a bar-type handle 13 and a steering shaft 14, and the left and right front wheels 2 are suspended from a front portion of a vehicle body frame 4 via an independent suspension type front suspension (not shown). Is done. On the other hand, the left and right rear wheels 3 are suspended from the rear portion of the body frame 4 via, for example, a swing arm type (axle suspension type) rear suspension (not shown). 2 indicates a rear wheel axle pipe through which the left and right rear drive shafts 12 are inserted.

  The rotational driving force of the front propeller shaft 6 is appropriately distributed and transmitted to the left and right front wheels 2 by a differential mechanism 17 provided integrally with the front speed reduction device 8, and the rotational driving force of the rear propeller shaft 7 is transmitted to the rear speed reduction device 9. Is distributed equally to the left and right rear wheels 3 via the. Here, the rear reduction gear 9 is different from the front reduction gear 8 only in that the differential mechanism 17 is not provided in this embodiment, and has the same configuration as that described later in the front reduction gear 8. The description is omitted. Depending on the vehicle model, the rear reduction gear 9 may have the differential mechanism 17.

  The shaft drive type vehicle 1 can be switched between a four-wheel drive mode in which the left and right front wheels 2 and the rear wheel 3 are respectively driven, and a two-wheel drive mode in which only the left and right rear wheels 3 are driven. Specifically, the front reduction gear 8 includes a clutch mechanism 18 (described later) that interrupts power transmission from the front propeller shaft 6.

  As shown in FIG. 4, the front speed reducer 8 is configured such that the differential mechanism 17 formed by combining four bevel gears and the front end portion (connecting portion) 6 a of the front propeller shaft 6 are connected to the front propeller shaft 6. Is integrally provided with a bevel gear transmission mechanism 16 for converting the power from the drive shaft 11 to the power of the left and right front drive shafts 11. Hereinafter, an axis along the front-rear direction at the front end 6a of the front propeller shaft 6 is indicated by Y.

  The differential mechanism 17 has left and right differential side gears 21 that share a rotation axis along the left-right direction and face each other, and a pair of differential pinion gears 22 that mesh with the left and right differential side gears 21 and share a rotation axis that is orthogonal to the left-right direction. These are housed in the differential case 23. The inner ends of the left and right front drive shafts 11 are spline-connected to the central portion of the left and right differential side gears 21, respectively. Hereinafter, an axis along the left-right direction at the inner end of the left / right front drive shaft 11 is indicated by X.

  Both differential pinion gears 22 are supported by a ring gear 24 arranged coaxially with the left and right differential side gears 21 via a carrier 24a, so that they can revolve together with the ring gear 24 in addition to rotation. The ring gear 24 is a part of the bevel gear transmission mechanism 16 and meshes with a drive pinion gear 25 arranged coaxially with the front end portion 6a of the front propeller shaft 6. Both gears 24 and 25 constitute a bevel gear pair, which changes the rotational direction of the power of the front propeller shaft 6 and performs final deceleration.

  In the state where the power of the front propeller shaft 6 is transmitted to the bevel gear shaft 27, when the movement distance of the left and right front wheels 2 is equal, such as when the shaft-driven vehicle 1 travels linearly, both differentials revolving together with the ring gear 24 Both the differential side gears 21 are rotated without the pinion gear 22 rotating, and the left and right front wheels 2 are driven at the same rotational speed via the left and right front drive shafts 11 connected thereto.

  On the other hand, when there is a difference in the moving distance of the left and right front wheels 2 such as during cornering of the shaft drive type vehicle 1, the rotational speed of the inner front wheels 2 tends to decelerate due to resistance from the road surface. Accordingly, both the differential pinion gears 22 appropriately rotate to cause a difference in rotational speed between the differential gears 21, thereby matching the moving distance and the rotational speed of the left and right front wheels 2.

  Referring also to FIG. 5, the bevel gear transmission mechanism 16 includes a joint 26 to which the front end portion 6 a of the front propeller shaft 6 is connected, and the power of the front propeller shaft 6 transmitted through the joint 26 to the ring gear 24. A bevel gear shaft 27 for transmission, and the clutch mechanism 18 for switching the connection state between the joint 26 and the bevel gear shaft 27 to interrupt power transmission from the front propeller shaft 6, and these are connected to the rear of the differential case 23. It is accommodated in a provided housing 28.

  The joint 26 has a front portion 31 in a columnar shape, while a rear portion has a slightly larger diameter and a bottomed cylindrical yoke portion (connecting portion) 32 that opens rearward, and a front propeller shaft in the yoke portion 32. The front end 6a of 6 is inserted and connected. An inner spline extending in the front-rear direction is formed on the inner periphery of the yoke portion 32, and a spherical spline corresponding to the inner spline is formed on the outer periphery of the front end portion 6 a of the front propeller shaft 6. That is, the outer periphery of the front end portion 6a of the front propeller shaft 6 is formed in a spherical shape, and the spherical spline is formed on the outer periphery of the spherical shape. Thus, even when the front propeller shaft 6 swings and swings with respect to the joint 26, the swing is absorbed in a state where the joint 26 and the front propeller shaft 6 are spline-connected to each other. .

  An outer wall surface 33 perpendicular to the axis Y is formed on the outer periphery of the front and rear intermediate portion (front side of the bottom surface of the yoke portion 32) of the joint 26, and the outer periphery of the portion immediately in front of the outer wall surface 33 is the housing. 28 is supported on the inner periphery of the rear hub portion 34 formed at the rear end portion via a rear ball bearing (outer bearing) 35 so as to be rotatable around the axis Y. The outer wall 33 is in contact with the rear surface of the inner race of the rear ball bearing 35, and the front surface of the inner race is in contact with the rear surface of the outer circlip 33 a mounted on the outer periphery of the front portion 31 of the joint 26.

  On the other hand, an inner wall surface 36 perpendicular to the axis Y is formed on the inner periphery of the rear hub portion 34 of the housing 28, and the front surface of the outer race of the rear ball bearing 35 is in contact with the inner wall surface 36. The rear surface comes into contact with the front surface of the inner circlip 36a attached to the inner periphery of the rear hub portion 34. Accordingly, the joint 26 is positioned in the front-rear direction with respect to the housing 28 via the rear ball bearing 35.

  A small-diameter projection 37 having a cylindrical shape coaxial with the front end of the joint 26 is projected forward, and the small-diameter projection 37 is recessed in the rear end of the bevel gear shaft 27. 38, and the outer periphery of the small-diameter protrusion 37 is fitted to the inner periphery of the support hole 38 via the needle bearing 39, so that the front end portion of the joint 26 and the rear end portion of the bevel gear shaft 27 are aligned with each other. It is connected so as to be relatively rotatable around Y.

  In the bevel gear shaft 27, the rear portion 41 forms a columnar shape having the same diameter as the front portion 31 of the joint 26, while the front portion 42 is provided with a slightly larger diameter, and the outer circumference of the front half portion of the front portion 42 is The drive pinion gear 25 that meshes with the ring gear 24 is formed. An outer wall surface 43 perpendicular to the axis Y is formed on the outer periphery of the front and rear intermediate portion of the bevel gear shaft 27, and the outer periphery of the portion immediately behind the outer wall surface 43 is the inner periphery of the front and rear intermediate portion of the housing 28. Are supported rotatably around the axis Y via a front ball bearing (outer bearing) 44. The front surface of the inner race of the front ball bearing 44 is in contact with the outer wall surface 43 via a shim 45.

  On the other hand, an inner wall surface 46 perpendicular to the axis Y is formed on the inner periphery of the housing 28, the front surface of the outer race of the front ball bearing 44 abuts on the inner wall surface 46, and the rear surface of the outer race is the housing 28. It abuts against the front surface of a ring-shaped lock nut 46a screwed to the inner periphery. By tightening the lock nut 46a, the front ball bearing 44 is positioned in the front-rear direction with respect to the housing 28, and the position of the bevel gear shaft 27 in the front-rear direction with respect to the front ball bearing 44 is set to the thickness of the shim 45. By adjusting according to this, the meshing between the drive pinion gear 25 and the ring gear 24 can be adjusted.

  At the front end of the bevel gear shaft 27, a small-diameter protrusion 47 having a cylindrical shape coaxial with the bevel gear is projected forward, and the small-diameter protrusion 47 is recessedly provided inside the front wall 51 of the housing 28. The front end of the bevel gear shaft 27 is placed inside the front wall 51 of the housing 28 by being inserted into the hole 48 and the outer periphery of the small-diameter protrusion 47 is fitted to the inner periphery of the support hole 48 via the needle bearing 49. It is supported rotatably about the axis Y.

  Referring also to FIG. 3, the housing 28 has a substantially cylindrical shape that shares the axis Y, the rear end portion is slightly reduced in diameter to form the rear hub portion 34, and the front end portion is tapered and closed. A front wall 51 is formed. The housing 28 is divided into a front and a rear by a split surface D orthogonal to the axis Y at the front and rear intermediate portion thereof, and the front and rear flange portions that abut against the split surface D are bolted together to be integrally coupled. The housing 28 is offset to the left with respect to the differential case 23 that houses the differential mechanism 17 and the ring gear 24, and the front right side of the housing 28 is integrally connected to the rear left side of the differential case 23.

  The differential case 23 is formed in a bottomed cylindrical shape whose left side portion is relatively shallow in the left-right direction and opened toward the right side, while the right side portion is relatively deep in the left-right direction and contracts in steps toward the right side. It is formed in a cup shape with a diameter. Left and right hub portions 56 and 57 through which the left and right front drive shafts 11 are inserted are respectively formed in the center of the left and right sides of the differential case 23, and the inner ends of the left and right front drive shafts 11 that have entered the differential case 23 from the left and right hub portions 56 and 57. The respective parts are splined to the central part of the left and right differential side gears 21, respectively. The axis X of the left and right front drive shaft 11 and the axis Y of the front propeller shaft 6 are orthogonal to each other immediately in front of the housing 28.

  The differential mechanism 17 is accommodated in the right side portion of the differential case 23, and the ring gear 24 is accommodated in the left side portion. A carrier 24a that supports both differential pinion gears 22 is bolted to the right side of the ring gear 24, the outer periphery of the left side of the ring gear 24 is the inner periphery of the left hub portion 56 on the left side of the differential case 23, and the outer periphery of the right side of the carrier 24a is the differential case 23. The inner periphery of the right hub portion 57 on the right side is supported so as to be rotatable around the axis X via left and right ball bearings 58 and 59, respectively.

The right and left side portions of the differential case 23 are divided into left and right parts by a dividing surface E perpendicular to the left and right direction, and are integrally coupled by bolting the left and right flange portions that abut against the dividing surface E. The left side of the differential case 23 is formed integrally with the housing 28.
A portion of the housing 28 located on the outer peripheral side of the rear end portion of the bevel gear shaft 27 and the front end portion of the joint 26 is slightly changed to the outer peripheral side to enlarge the internal space. The clutch mechanism 18 that interrupts power transmission between the gear shaft 27 and the joint 26 is accommodated.

  Referring also to FIG. 6, the clutch mechanism 18 slides along the front-rear direction in a state in which the range extending between the rear rear half of the bevel gear shaft 27 and the front front half of the joint 26 is fitted to the outer periphery thereof. Clutch sleeve 61, a clutch fork 62 fitted to the outer periphery of the clutch sleeve 61 and rotatably supported about the axis Y, and the clutch fork 62 can be swung about a swing shaft along the left-right direction. The clutch shaft 63 is mainly supported. The left end portion of the clutch shaft 63 protrudes outside the housing 28, and a clutch arm 64 is attached to the left end portion.

  Inner splines extending in the front-rear direction are formed on the inner periphery of the clutch sleeve 61, and the outer splines corresponding to the inner splines are similarly provided on the outer periphery of the rear rear half of the bevel gear shaft 27 and the outer periphery of the front front half of the joint 26, respectively. It is formed. The clutch fork 62 is formed in a semicircular shape along the outer periphery of the upper half of the clutch sleeve 61 when viewed from the front, and the slider 65 supported by the lower left and right ends of the clutch fork 62 is fitted to the outer periphery of the clutch sleeve 61. Bolts are fastened to the left and right intermediate portions of the shaft 63.

  The clutch fork 62 is urged so that the lower end thereof is positioned forward by the spring force of the torsion spring 66 wound around the outer periphery of the clutch shaft 63, and the clutch sleeve together with the lower end of the clutch fork 62 is urged by this urging force. When 61 moves forward and the clutch sleeve 61 is engaged with only the bevel gear shaft 27 without being engaged with the joint 26, the driving force from the joint 26 is not transmitted to the bevel gear shaft 27 but left and right. The two-wheel drive mode in which the front wheels 2 are not driven is set.

  On the other hand, the clutch arm 64 is swung electrically or manually via an operation wire or the like (shown by a chain line in FIG. 3), and the clutch shaft 63 and the clutch fork 62 are swung against the urging force of the torsion spring 66. As a result, the clutch sleeve 61 moves rearward together with the lower end portion of the clutch fork 62 (shown by a chain line in FIG. 5), and the clutch sleeve 61 straddles the front end portion of the joint 26 and the rear end portion of the bevel gear shaft 27. When in the engaged state, the driving force from the joint 26 can be transmitted to the bevel gear shaft 27 and the left and right front wheels 2 are driven. A clutch detection switch 67 is provided on the right side of the housing 28 to detect which drive mode the clutch sleeve 61 is in.

  Here, the front propeller shaft 6 is urged toward the joint 26 by the urging force of the shock absorbing damper during torque fluctuation, and the front end portion 6a of the front propeller shaft 6 is connected to the yoke portion 32 of the joint 26. It abuts against the bottom 32a. That is, the front end portion 6a of the front propeller shaft 6 and the bottom portion 32a of the yoke portion 32 constitute an abutting portion with respect to the other.

  The front end 6a of the front propeller shaft 6 is provided with a conical protrusion 68 that protrudes forward (from the bottom 32a side of the yoke 32) toward the front end surface perpendicular to the axis Y. The protrusion 68 is provided so as to be coaxial with the front end portion 6 a of the front propeller shaft 6, the joint 26, and the bevel gear shaft 27, and the tip of the protrusion 68 contacts the center of the bottom surface perpendicular to the axis Y at the bottom portion 32 a of the yoke portion 32. By contacting, the butting gear transmission mechanism 16 and the front propeller shaft 6 can be abutted without impeding relative swinging.

  As described above, the shaft drive type vehicle 1 in the above embodiment has the front propeller shaft 6 for transmitting the output from the engine 5 and the power transmitted from the front propeller shaft 6 to which the front propeller shaft 6 is connected. And a bevel gear transmission mechanism 16 for transmitting the left and right front drive shafts 11 to the abutting portion (front end portion 6a) of the front propeller shaft 6 with the joint 26 of the bevel gear transmission mechanism 16. 26 is provided with a conical projection 68 that abuts against the H.26.

According to this configuration, since the projection 68 that abuts against the bevel gear transmission mechanism 16 in the front propeller shaft 6 is conical, the contact area between the projection 68 and the bevel gear transmission mechanism 16 is reduced. Compared with the case where the contact area is relatively large as in the case where the trapezoidal protrusion is provided, scattering due to the centrifugal force of the lubricating oil at the contact portion is suppressed, and lubrication between these can be easily performed.
Further, since the front propeller shaft 6 and the bevel gear transmission mechanism 16 are substantially point-contacted on the front end 6a of the front propeller shaft 6 and the axis Y of the joint 26, the front propeller shaft 6 and the bevel gear transmission mechanism 16 are in contact with each other. Since it becomes relatively easy to swing, the vibration of the front propeller shaft 6 can be satisfactorily absorbed and power can be transmitted smoothly.

  In the shaft drive type vehicle 1, the front end portion 6 a of the front propeller shaft 6 and the yoke portion 32 of the bevel gear transmission mechanism 16 are spline-connected, and a spherical spline is formed on the outer periphery of the front end portion 6 a of the front propeller shaft 6. By being formed, the vibration of the front propeller shaft 6 can be absorbed even better.

Next, a second embodiment of the present invention will be described with reference to FIG.
The shaft drive type vehicle in this embodiment is different from the first embodiment in that the projection 168 for abutting the front propeller shaft 6 and the joint 26 is not the front end portion 6a of the front propeller shaft 6 but the joint 26. The difference is mainly in the point provided on the bottom 32a of the yoke part 32, and the same reference numerals are given to the same parts as those in the previous embodiment, and the description thereof is omitted.

  In the bevel gear transmission mechanism 116 of this embodiment, a conical projection 168 is provided on the bottom 32a of the yoke portion 32 of the joint 26 so as to project rearward (front propeller shaft 6 side) from the bottom surface orthogonal to the axis Y. . The protrusion 168 is provided so as to be coaxial with the front end portion 6 a of the front propeller shaft 6, the joint 26, and the bevel gear shaft 27, and a tip end surface of the front end portion 6 a of the front propeller shaft 6 is perpendicular to the axis Y. By abutting on the center, the butting gear transmission mechanism 116 and the front propeller shaft 6 can be abutted without impeding relative swinging.

  In this embodiment, a small-diameter protrusion 137 having a cylindrical shape coaxial with the bevel gear shaft 27 protrudes rearward from the rear end of the bevel gear shaft 27, and the small-diameter protrusion 137 is a front end of the joint 26. And the outer periphery of the small-diameter projection 137 is fitted to the inner periphery of the support hole 138 via a needle bearing 139, so that the front end portion of the joint 26 and the bevel gear shaft 27 are inserted into the support hole 138. Is connected to the rear end portion so as to be relatively rotatable about the axis Y.

According to the second embodiment, since the projection 168 that strikes the front propeller shaft 6 in the bevel gear transmission mechanism 116 is conical, the contact area between the projection 168 and the front propeller shaft 6 is reduced. The lubrication between them can be easily performed.
Further, since the front propeller shaft 6 and the bevel gear transmission mechanism 116 are substantially in point contact, the front propeller shaft 6 and the bevel gear transmission mechanism 116 are relatively easy to swing, so that the swing of the front propeller shaft 6 is prevented. It absorbs well and can transmit power smoothly.

Next, a third embodiment of the present invention will be described with reference to FIG.
The shaft drive type vehicle in this embodiment extends the shaft portion 237 from the rear end portion of the bevel gear shaft 27 rearward with respect to that of the second embodiment, and the shaft portion 237 is in front of the joint 26. Each embodiment differs mainly in that a projection 268 corresponding to the projection 168 is formed on the rear end portion (butting portion) 237a of the shaft portion 237 while penetrating the portion 31 (hollow portion). The same parts are denoted by the same reference numerals and the description thereof is omitted.

  In the bevel gear transmission mechanism 216 of this embodiment, from the rear end portion of the bevel gear shaft 27, the shaft portion 237 extends rearward from the center of the rear end on the axis Y, while the front portion 31 of the joint 26. Is formed with a through hole 238 penetrating the axial center portion in the front-rear direction. A shaft portion 237 is inserted into the through-hole 238, and the outer periphery of the shaft portion 237 is fitted to the inner periphery of the through-hole 238 via front and rear needle bearings (inner bearings) 239a and 239b. 31 and the shaft portion 237 are connected to be rotatable around the axis Y. The shaft portion 237 corresponds to the small-diameter protrusion 137 extending rearward, and the through hole 238 corresponds to the support hole 138 penetrating to the bottom surface of the yoke portion 32.

  The rear needle bearing 239b that supports the rear outer periphery of the shaft portion 237 is substantially aligned with the rear ball bearing 35 that supports the outer periphery of the joint 26 in the front-rear direction. It is supported on the inner wall of the housing 28 via the needle bearing 239b, the joint 26, and the rear ball bearing 35.

  The rear end portion 237a of the shaft portion 237 reaches the bottom portion 32a of the yoke portion 32, and the rear end portion 237a protrudes backward from the bottom surface orthogonal to the axis Y of the bottom portion 32a of the yoke portion 32. 268 is formed. The protrusion 268 is provided so as to be coaxial with the front end portion 6 a of the front propeller shaft 6, the joint 26, and the bevel gear shaft 27, and a tip end surface of the front end portion 6 a of the front propeller shaft 6 is perpendicular to the axis Y. By abutting on the center, the butting gear transmission mechanism 216 and the front propeller shaft 6 can be abutted without impeding relative swinging.

According to the third embodiment, the shaft portion 237 of the bevel gear shaft 27 is supported by the hollow portion (front portion 31) of the joint 26, thereby increasing the size of the front and rear ball bearings 35 and 44 and the bevel gear transmission mechanism 216. While suppressing the increase in size, the number of supporting portions of the bevel gear shaft 27 that receives the meshing reaction force of the bevel gear can be increased and this can be favorably supported.
In addition, since the support of the bevel gear shaft 27 is improved, the power transmission and disconnection by the clutch mechanism 18 can be smoothly performed.
Further, in the two-wheel drive mode, even if there is a rotational difference between the front propeller shaft 6 and the bevel gear shaft 27, they are almost in point contact, so that the sliding resistance is suppressed.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
The shaft drive type vehicle in this embodiment is different from that of the third embodiment in that the shaft portion 337 of the bevel gear shaft 127 and the front portion 131 (hollow portion of the joint 126) are adapted only to the four-wheel drive mode. ), And the point that the clutch mechanism 18 is eliminated is mainly different, and the same reference numerals are given to the same parts as those of the above-described embodiments, and the description thereof is omitted.

  In the bevel gear transmission mechanism 316 of this embodiment, the joint 126 has a front portion 131 that extends forward with respect to the joint 26, and the outer periphery of the front end portion of the front portion 131 is interposed through the front ball bearing 44. 28 is rotatably supported around the axis Y on the inner circumference. On the other hand, the bevel gear shaft 127 is shortened in the front-rear direction by eliminating the front portion 41 with respect to the bevel gear shaft 27, and the rear end thereof is disposed in front of the front end of the joint 126. The front surface of the inner race of the front ball bearing 44 is in contact with the rear end of the bevel gear shaft 127 via a shim 45. From the center of the rear end of the bevel gear shaft 127, the shaft portion 337 extends rearward on the axis Y, while the front portion 131 of the joint 126 penetrates the shaft center portion along the front-rear direction. A through hole 338 is formed.

  An inner spline extending in the front-rear direction is formed on the inner periphery of the through-hole 338, and an outer spline corresponding to the inner spline is formed on the outer periphery of the shaft portion 337, and the through-hole 338 is fitted to fit both the splines. By inserting the shaft portion 337 into the shaft, the front portion 131 of the joint 126 and the shaft portion 337 are connected in a relatively non-rotatable manner, and the shaft portion 337 of the bevel gear shaft 127 is connected to the front portion 131 of the joint 126 and the front and rear ball bearings. It is supported on the inner wall of the housing 28 via 35 and 44.

  The rear end portion 337a (butting portion) of the shaft portion 337 reaches the bottom portion 32a of the yoke portion 32, and the rear end portion 337a has a conical shape that protrudes rearward from the bottom surface orthogonal to the axis Y of the yoke portion 32. The protrusion 368 is formed. The protrusion 368 is provided so as to be coaxial with the front end portion 6 a of the front propeller shaft 6, the joint 126, and the bevel gear shaft 127, and the front end of the protrusion 368 is a front end surface perpendicular to the axis Y of the front end portion 6 a of the front propeller shaft 6. By abutting on the center, they can be abutted without hindering relative swinging of the bevel gear transmission mechanism 316 and the front propeller shaft 6.

  According to the fourth embodiment, the shaft portion 337 of the bevel gear shaft 127 is supported by the hollow portion (front portion 131) of the joint 126, thereby increasing the size of the front and rear ball bearings 35 and 44 and the bevel gear transmission mechanism 316. While suppressing an increase in size, the number of supporting portions of the bevel gear shaft 127 that receives the meshing reaction force of the bevel gear can be increased and stably supported.

The present invention is not limited to the above embodiments. For example, the front end portion of the front propeller shaft may be a yoke portion, and the rear portion of the joint may be inserted into the yoke portion. In this case, a spherical spline is formed on the outer periphery of the rear part of the joint.
Here, as an application example of the fourth embodiment, as shown in FIG. 10, the front portion 131 of the joint 126, the shaft portion 337 of the bevel gear shaft 127, and the housing 28 are shortened, and the rear hub portion 34 and the rear hub portion 34 are rearranged. If the ball bearing 35 is eliminated, and the shaft portion 337 of the bevel gear shaft 127 and the front portion 131 of the joint 126 are supported by the inner wall of the housing 28 only through the front ball bearing 44, the number of parts is reduced and the size and weight are reduced. be able to. In the fourth embodiment, the bevel gear shaft 127 and the joint 126 can be integrated.
The configuration in each of the above embodiments is an example of the present invention, and can be applied to a rear reduction gear that does not have a differential mechanism, and can be applied to a normal four-wheeled vehicle or two-wheeled vehicle. It goes without saying that various changes can be made without departing from the scope.

It is a side view of the shaft drive type vehicle in the Example of this invention. It is a top view of the drive system of the said shaft drive type vehicle. It is a side view of the front speed reducer of the shaft drive type vehicle. It is AA sectional drawing in FIG. It is a principal part enlarged view of FIG. It is BB sectional drawing in FIG. It is sectional drawing corresponded in FIG. 5 in 2nd Example of this invention. FIG. 6 is a cross-sectional view corresponding to FIG. 5 in a third embodiment of the present invention. It is sectional drawing equivalent to FIG. 5 in 4th Example of this invention. It is sectional drawing equivalent to FIG. 5 which shows the application example of the said 4th Example.

Explanation of symbols

1 Shaft drive type vehicle 5 Engine 6 Front propeller shaft (propeller shaft)
6a Front end (butting part, connecting part)
11 Front drive shaft (wheel axle)
16, 116, 216, 316 Bevel gear transmission mechanism 18 Clutch mechanism 26, 126 Joint 27, 127 Bevel gear shaft 28 Housing 31, 131 Front (hollow part)
32 Yoke part (connection part)
32a Bottom part (butting part)
35 Rear ball bearing (outer bearing)
44 Front ball bearing (outer bearing)
68,168,268,368 Projection 237,337 Shaft 237a, 337a Rear end (butting portion)
239a Front needle bearing (inner bearing)
239b Rear needle bearing (inner bearing)
Y axis

Claims (4)

In a shaft drive type vehicle including a propeller shaft that transmits output from an engine, and a bevel gear transmission mechanism that is connected to the propeller shaft and transmits power transmitted from the propeller shaft to a wheel shaft.
A conical protrusion abutting against the other is provided at the abutting portion with the other of the propeller shaft and the bevel gear transmission mechanism ,
The bevel gear transmission mechanism accommodates the joint to which the propeller shaft is connected, the bevel gear shaft that transmits the power of the propeller shaft transmitted from the joint to the wheel shaft, and the joint and the bevel gear shaft. A housing that supports these via outer bearings, the joint is formed in a hollow shape, the shaft portion of the bevel gear shaft passes through the hollow portion, and the shaft portion is supported by the hollow portion, The shaft drive type vehicle is characterized in that the projection is formed at the tip of the shaft portion . In a shaft drive type vehicle including a propeller shaft that transmits output from an engine, and a bevel gear transmission mechanism that is connected to the propeller shaft and transmits power transmitted from the propeller shaft to a wheel shaft.
A conical protrusion abutting against the other is provided at the abutting portion with the other of the propeller shaft and the bevel gear transmission mechanism,
The bevel gear transmission mechanism includes a joint to which the propeller shaft is connected, a bevel gear shaft that transmits the power of the propeller shaft transmitted from the joint to the wheel shaft, and a connection state between the joint and the bevel gear shaft. A clutch mechanism for intermittently transmitting power from the propeller shaft and housing the joint, the bevel gear shaft, and the clutch mechanism, and supporting the joint and the bevel gear shaft via outer bearings, respectively. The joint is formed in a hollow shape, the shaft portion of the bevel gear shaft passes through the hollow portion, the shaft portion is supported by the hollow portion via an inner bearing, and the tip portion of the shaft portion A shaft drive type vehicle characterized in that a protrusion is formed. The shaft drive type vehicle according to claim 1, wherein the protrusion is provided on an axis of the propeller shaft. The shaft drive according to any one of claims 1 to 3, wherein the propeller shaft and the bevel gear transmission mechanism are spline-connected, and a spherical spline is formed at one of these connecting portions. Type vehicle.

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