JPS6333689Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention relates to a structure for interconnecting drive shafts that transmit power to the front and rear wheels, respectively, in a power transmission system for a four-wheel drive vehicle that simultaneously drives the front and rear wheels. It is.

Prior Art This invention was invented in April 1985 as a power transmission device for a four-wheel drive vehicle that simultaneously drives the front and rear wheels before this application was filed.
The application was filed as Japanese Patent Application No. 60-84284 (see Japanese Patent Application Laid-open No. 61-24219) on August 19th.

In the invention of Japanese Patent Application No. 60-84284, as shown in FIG.
and a second drive shaft 03 that drives the front wheels.
A cylindrical coupling ring 05 was fitted to the rear end portion 04, and the drive shaft front end portion 02 and the drive rear end portion 04 were integrally coupled to the coupling ring 05 by tightening the bolt 06. .

Problems to be Solved by the Invention In the conventional power transmission system for a four-wheel drive vehicle as shown in FIG. Because they are connected, the production of the Coupling 05 requires complex processes such as molding the material by forging, machining slits, counterboring the two bolt holes, and machining the taps.Furthermore, after inserting into the bolt hole, The bolts had to be tightened at certain locations, which required a large number of manufacturing steps, and it was difficult to downsize the coupling ring 05.

Means and operation for solving the problem The output shaft has an output shaft disposed parallel to the engine crankshaft parallel to the axle, and a gear portion meshing with a gear portion formed on the output shaft, and perpendicular to the output shaft. a first drive shaft disposed in the front-rear direction and transmitting power to one of the front and rear wheels; a case supporting the output shaft and the first drive shaft and removably fitting into the engine; ,
a coupling that integrally connects the first drive shaft and the second drive shaft described below;
A second drive shaft is supported on an extension of the first drive shaft, is detachably connected via the coupling, and transmits power to the other of the front and rear wheels.
In the power transmission device for a four-wheel drive vehicle comprising a drive shaft, a spline capable of sliding in the axial direction is formed on the connecting ends of the first and second drive shafts and on the inner peripheral surface of the coupling ring, and Since the coupling ring is disposed outside the case that supports the first drive shaft and is brought into contact with the bearing that supports the first drive shaft, the coupling end of the coupling end of the first and second drive shafts can be moved in the axial direction. By moving and fitting the first and second drive shafts, the first and second drive shafts can be integrally coupled so as not to rotate relative to each other.

In the power transmission device, a restricting member that restricts only the axial movement of the coupling toward the second drive shaft is fitted into a circumferential groove formed in the second drive shaft, so that the axial movement of the coupling is restricted by the restricting member, thereby maintaining the integral connection of the first and second drive shafts.

Embodiment An embodiment of the present invention illustrated in FIGS. 2 to 10 will be described below.

Reference numeral 1 denotes a four-wheel drive vehicle commonly referred to as a straddle-type buggy vehicle, and an engine 3 configured for a two-wheeled motor vehicle is mounted in the center of a body frame 2 of the four-wheel drive vehicle 1.

Further, the front wheel 4 and the rear wheel 5 are pivotally connected to the tips of a front fork assembly 6 and a rear fork assembly 7, respectively, and the base ends of the front fork assembly 6 and rear fork assembly 7 are connected to a swing arm pivot 42 and a swing arm pivot 42, respectively. The tips of the front fork assembly 6 and the rear fork assembly 7 are supported on the vehicle body frame 2 via a bolt 43 so as to be able to swing up and down, and the tips of the front fork assembly 6 and the rear fork assembly 7 are connected to the vehicle body via a front wheel suspension device 8 and a rear wheel suspension device 9, respectively. It is supported by frame 2.

Furthermore, a centrifugal clutch 12 is fitted to the crankshaft 11 which is rotatably supported by the crankcase 10 of the engine 3, and the centrifugal clutch 12 becomes connected when a predetermined rotational speed is exceeded.A crank gear 13 is attached to the centrifugal clutch 12. has been done.

Furthermore, a multi-plate clutch 15 is fitted into the main shaft 14, which is rotatably supported on the crankcase 10 adjacent to and parallel to the crankshaft 11, and the input gear 16 of the multi-plate clutch 15 is connected to the When the crankshaft 11 is engaged with the crank gear 13, the rotational speed of the crankshaft 11 exceeds a predetermined rotational speed, and the multi-plate clutch 15 is connected by the clutch operation mechanism 17, the rotation of the crankshaft 11 is transmitted to the main shaft 14. It's becoming like that.

Further, a countershaft 19 is rotatably supported on the crankcase 10 adjacent to and parallel to the mainshaft 14.
The main shaft gear group 18 fitted to the main shaft gear 4 and the countershaft gear group 20 fitted to the countershaft 19 are selectively engaged with each other by a speed change operation mechanism (not shown), so that the countershaft gear can be adjusted at a required speed ratio. 19 is designed to be rotationally driven.

Furthermore, the output shaft 23 is rotatably fitted to the crankcase 10 and a bearing 26 is rotatably fitted to the output shaft case 22 so that the gear 24 of the output shaft 23 meshes with the output side counter gear 21 of the countershaft 19. The output shaft case 22 is fitted with a bearing 27 that pivotally supports a first drive shaft 29, which will be described later.

Furthermore, the output bevel gear 2 of the output shaft 23
5, the bevel gear 30 of the first drive shaft 29
The first drive shaft case 28, which pivotally supports the first drive shaft 29 via the bearing 31, is integrally attached to the output shaft case 22 by bolts (not shown) so that the first drive shaft 29 is engaged with the first drive shaft case 28.

Moreover, a second drive shaft pivot portion 34 is disposed at the front portion of the crankcase 10 located on an extension line of the first drive shaft 29 , and the second drive shaft pivot portion 34 is provided with a second drive shaft pivot portion 34 .
5 is rotatably supported via a bearing 38, and the front end spline 33 of the first drive shaft 29 and the second drive shaft 35
The rear end spline 36 is spline-fitted to a coupling ring 39, and the front end of the coupling ring 39 is connected to the circumferential groove 35a of the second drive shaft 35.
A circlip 40 that is engaged with the drive shaft 35 and a collar 41 that is fitted to the drive shaft 35 are used to prevent the drive shaft from slipping out forward.

An oil seal 48 is fitted to the rear end of the coupling ring 39 and the output shaft case 22, and an O-ring 49 is fitted to the front part of the coupling ring 39 and the second drive shaft 35. The oil in the output shaft case 22 that lubricates the drive shaft 35 is transferred to the oil seal 4.
8. O-ring 49 prevents leakage.

Further, a rear wheel drive shaft 46 and a front wheel drive shaft 47 are connected to the rear end spline 32 of the first drive shaft 29 and the front end spline 37 of the second drive shaft 35 via universal joints 44 and 45, and the front fork Swing arm pivot 4 which is the base end pivot portion of the assembly 6 and rear fork assembly 7
2. Move the first drive shaft case 28 and the second drive shaft pivot 34 so that the first drive shaft 29 and the second drive shaft 35 are located on the line connecting the swing arm pivot 43.
are arranged, and the universal joints 44 and 45 are arranged so that they intersect and are located on a line connecting the left and right pairs of swing arm pivots 43 and swing arm pivots 42.
4 and 45 are arranged.

Furthermore, as shown in FIG. 4, the front, middle, and rear mounting parts 51 of the drive shaft cover 50 are attached to the vehicle body by bolts 54 (only the front bolts are shown, and the rear bolts are not shown) that are inserted into the holes 52. The second drive shaft 35 is surrounded by a drive shaft cover 50 for dust protection and aesthetics. Note that the width center portion 53 of the drive shaft cover 50 is as shown in FIGS. 6 to 8.
It is curved outwardly as shown in the figure.

Furthermore, a speedometer take-out cap 55 is detachably attached to the crankcase 10 with bolts 56 so that the left end of the countershaft 19 can be exposed to the outside of the crankcase 10.

A filter element 58 is built into the oil filter 57 shown in the upper left part of FIG. As shown in the figure, the outside of the filter element 58 is connected to an outflow passage 61
The outlet of the oil cooler is connected to each lubricating part of the engine 3 via a pipe 63 and an oil passage 64, and is stored at the bottom of the crankcase 10. The ivy oil is supplied to the joint 60, the inflow passage 59, the filter element 58, the outflow passage 61, and the pipe 6 by an oil pump (not shown).
2. The oil is sent to each lubricating part of the engine 3 via an oil cooler (not shown), a pipe 63, and an oil passage 64. Therefore, the pipes 62 and 63 have an O-ring 65, an abutting member 66, a holding member 67, and a bolt 6 as shown in FIG.
8, it is oil-tightly connected to the outflow passage 61 and the oil passage 64.

The embodiment shown in FIGS. 3 to 10 is constructed as described above, so that when the engine 3 starts operating and exceeds the rotational speed at which the centrifugal clutch 12 is engaged, the multi-disc clutch 15 is engaged. When the main shaft gear group 18 and the countershaft gear group 20 are properly engaged at a predetermined gear ratio, the rotational force of the crankshaft 11 is transmitted to the centrifugal clutch 12, the crank gear 13, and the input gear 16. , multi-plate clutch 15, main shaft 1
4. Transmitted to the output bevel gear 25 via the main shaft gear group 18, countershaft gear group 20, countershaft 19, counter gear 21, gear 24, and output shaft 23, and the bevel gear 30 meshing with the output bevel gear 25 is rotationally driven. The rotational force is generated by the first gear which is integrated with the bevel gear 30.
The rear wheel 5 is connected to the rear wheel 5 from the drive shaft 29 via the universal joint 44 and the rear wheel drive shaft 46.
The power is transmitted to the front wheels 4 via the coupling ring 39, the second drive shaft 35, the universal joint 45, and the front wheel drive shaft 47, so that the vehicle 1 runs in four-wheel drive.

Further, the first drive shaft 29 and the second drive shaft 35 are arranged on a front-rear direction line connecting the swing arm pivot 43 and the swing arm pivot 42, and the left and right swing arm pivots 43,
Since the universal joint 45 and the universal joint 44 are arranged on the horizontal line connecting the swing arm pivots 42, the front fork assembly 6 and the rear fork assembly 7 can be connected to the swing arm pivot 42,
When swinging up and down about the swing arm pivot 43, the length of the wheel drive shaft hardly changes.

Furthermore, the motorcycle engine 3 is shared, and the output shaft case (not shown) for the motorcycle that pivotally supports the output shaft 23 is changed to the output shaft case 22, and the output bevel gear 25 of the output shaft 23 is changed to the output shaft case 22. Just by meshing the bevel gear 30 of the first drive shaft 29, there is no need to change the overall structure of the engine 3 or the shape of the crankcase 10, which makes it possible to mass-produce the engine 3 and reduce costs. Moreover, the engine 3 remains in the same shape, and the power system becomes compact.

Furthermore, since the rear end spline 36 of the second drive shaft 35 and the front end spline 33 of the first drive shaft 29 are located coaxially with the coupling ring 39 and are spline-fitted,
The rear end of the drive shaft 36 does not need to be supported by the vehicle body frame 2 via a bearing, and the number of parts and weight can be reduced.

Moreover, simply by removing the circlip 40 and shifting the collar 41 and the coupling 39 in the axial direction, the connection between the first drive shaft 29 and the second drive shaft 35 can be released, improving maintainability.

Furthermore, the coupling ring 39 can be manufactured at low cost since it can be made of a pipe-shaped material and does not require counterboring or tapping.

Furthermore, since the first drive shaft 29 and the second drive shaft 36 are spline-fitted to the coupling ring 39 and fixed by the circlip 40, ease of assembly and maintenance is improved.

Effects of the invention In the present invention, as described above, the connecting ends of the first and second drive shafts are spline-coupled via the coupling ring, so power transmission is ensured and slippage between the drive shafts is prevented. There is no power transmission loss due to

Further, in the present invention, the coupling ring is spline-fitted to the first and second drive shafts, and is disposed outside of the case supporting the first drive shaft, and is connected to the bearing supporting the first drive shaft. Since a regulating member is provided which is in contact with the circumferential groove formed in the second drive shaft and which regulates only the axial movement of the coupling ring in the direction of the second drive shaft, the regulation member By simply removing the member from the second drive shaft, the coupling ring can be moved in the direction of the second drive shaft, the coupling ring can be removed from the first drive shaft, and the assembly of the first and second drive shafts can be removed. Attachment and removal work, as well as work to connect both drive shafts, can be performed extremely easily, and maintainability can be greatly improved.

In addition, in the present invention, since the coupling ring does not have a hole for tightening a bolt or the like, it can be made into a thin pipe shape, and it can be made compact and the number of manufacturing steps can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional plan view of the main part of a conventional power transmission device for a four-wheel drive vehicle, and FIG. 2 is a perspective view illustrating an embodiment of a drive shaft coupling structure in a power transmission device for a four-wheel drive vehicle according to the present invention. Figure 3 is a partially cutaway side view of the drive shaft cover, Figure 4 is a longitudinal side view cut along the - line in Figure 3, Figure 5 is a side view of the drive shaft cover, and Figures 6, 7, and 8 are side views of the drive shaft cover. The figures are cross-sectional views taken along the -, -, - lines of Fig. 5, Fig. 9 is a cross-sectional view of the oil passage, and Fig. 1 is a cross-sectional view of the oil passage.
Figure 0 is an exploded perspective view of the main part. 1...4-wheel drive vehicle, 2...body frame, 3...
...Engine, 4...Front wheel, 5...Rear wheel, 6...Front fork assembly, 7...Rear fork assembly, 8...Front wheel suspension system, 9...Rear wheel suspension system, 10...Crank case ,
11...Crankshaft, 12...Centrifugal clutch, 1
3...Crank gear, 14...Main shaft,
15...Multi-plate clutch, 16...Input gear, 17
...Clutch operation mechanism, 18...Main shaft gear group, 19...Countershaft, 20...
Countershaft gear group, 21... Counter gear, 22... Output shaft case, 23... Output shaft,
24...Gear, 25...Output bevel gear, 26,
27... Bearing, 28... First drive shaft case, 29... First drive shaft, 3
0...Bevel gear, 31...Bearing, 32...
...Rear end spline, 33...Front end spline, 3
4... Second drive shaft pivot plate, 35... Second drive shaft, 36... Rear end spline,
37...Front end spline, 38...Bearing,
39...Cup ring, 40...Circlip,
41... Collar, 42, 43... Swing arm pivot, 44, 45... Universal joint, 46... Rear wheel drive shaft, 47... Front wheel drive shaft, 48... Oil seal, 49... O ring , 50... Drive shaft cover, 51... Mounting part, 52... Hole, 53...
...Central width, 54...Bolt, 55...Speedometer removal cap, 56...Bolt, 57...
...Oil filter, 58...Filter element, 59...Inflow passage, 60...Joint, 61...
Outflow passage, 62, 63... pipe, 64... oil passage, 65... O ring, 66... contact member,
67...Press member, 68...Bolt.

Claims (1)

[Scope of utility model registration request] It has an output shaft disposed parallel to the engine crankshaft parallel to the axle, and a gear portion that meshes with a gear portion formed on the output shaft, and is disposed perpendicularly to the output shaft in the front-rear direction. a first drive shaft that transmits power to one of the wheels; a case that supports the output shaft and the first drive shaft and is removably fitted to the engine;
a coupling that integrally connects the first drive shaft and the second drive shaft described below;
A second drive shaft is supported on an extension of the first drive shaft, is detachably connected via the coupling, and transmits power to the other of the front and rear wheels.
A power transmission device for a four-wheel drive vehicle comprising a drive shaft, wherein a spline slidable in the axial direction is formed on a connecting end of the first and second drive shafts and on an inner circumferential surface of the coupling ring, and the coupling The first drive shaft is disposed outside the case that supports the first drive shaft.
a regulating member that is in contact with a bearing that supports a drive shaft, is formed in the second drive shaft, and is fitted in a circumferential groove to restrict only axial movement of the coupling ring toward the second drive shaft; A drive shaft coupling structure characterized by being provided.