JPH0754134B2 - Vehicle power transmission device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission device for a vehicle, which shifts the power of an internal combustion engine to a predetermined gear ratio and transmits the power to a drive system.

[Conventional technology]

Some power transmission devices mounted on motorcycles transmit power of an internal combustion engine to a drive system at a predetermined gear ratio by a power transmission mechanism.

A conventional power transmission mechanism is configured to transmit the power of an internal combustion engine to an automatic starting clutch or a transmission via a power transmission shaft, for example. In this conventional example, the power is gradually transmitted at the time of starting to smoothly start, and the power can be shifted in a relatively wide range to accurately meet the demand on the drive system side.

[Problems to be solved by the invention]

In the conventional example in which the power of the internal combustion engine is transmitted to the automatic starting clutch and the transmission through the power transmission shaft, if a balancer that cancels the vibration of the internal combustion engine is provided, the balancer shaft rotates in synchronization with the crankshaft. Since it is arranged, it becomes difficult to secure a mounting space for the balancer shaft and the power transmission shaft. Moreover, since they are respectively meshed with the crankshaft and rotatably supported by the crankcase, the structure becomes complicated and the device becomes large.

The present invention has been made in view of the above points, and improves the function of the balancer and the responsiveness of the automatic starting centrifugal clutch,
An object of the present invention is to provide a power transmission device for a vehicle, which enables simplification and downsizing of the device.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a vehicle power transmission device including a centrifugal clutch for automatic start and a transmission between a crankshaft of an internal combustion engine and a drive system. A speed increasing mechanism and an intermediate rotary shaft are provided between the centrifugal clutch, and a balancer is arranged on the intermediate rotary shaft between the pair of crank webs of the crankshaft so as to face each other. A speed reduction mechanism composed of a clutch gear having a diameter smaller than that of the clutch plate of the automatic starting centrifugal clutch is interposed between the machine and the speed increasing mechanism and the speed reducing mechanism are arranged near the inside and outside of the crank case with the crank case sandwiched therebetween. The technical means is to dispose the generator on one end of the crankshaft and to dispose the centrifugal clutch for automatic start on the other end of the intermediate rotating shaft on the other side of the generator.

[Action]

In this invention, the rotation of the intermediate rotary shaft is accelerated by the speed increasing mechanism between the crankshaft and the intermediate rotary shaft of the internal combustion engine, and the balancer of the intermediate rotary shaft operates to cancel the vibration of the internal combustion engine.
The rotation of the intermediate rotation shaft is transmitted to the automatic starting centrifugal clutch, reduced by the reduction mechanism, and transmitted to the drive system via the transmission.

〔Example〕

 Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

A crankshaft 2 of an internal combustion engine 1 mounted on a motorcycle is rotatably supported by a crankcase 3, and a generator 4 is arranged at one end (the right end in the figure) of the crankshaft 2 and the other end thereof. A crank gear 5 is fixed to (the left end in the figure).
The crankshaft 2 is formed with a pair of left and right crank webs 51, 52.

An intermediate rotary shaft 6 of the power transmission mechanism is rotatably supported by the crankcase 3, and a crank gear 5 meshes with an input gear 7 fixed to the intermediate rotary shaft 6 of the power transmission mechanism. The speed increasing mechanism including the crank gear 5 and the input gear 7 is located inside the crankcase 3 and near the crankcase 3. On the intermediate rotary shaft 6, balancers 8 and 9 are provided at positions facing each other between a pair of left and right crank webs 51 and 52 of the crank shaft 2.
Are integrally formed (the crankshaft 2 and the intermediate rotary shaft 6
When and are rotating, the balancers 8 and 9 momentarily pass between the pair of crank webs 51 and 52), and the intermediate rotation shaft 6 also functions as a balancer shaft. An automatic starting centrifugal clutch 10 is provided on the other end of the intermediate rotating shaft 6 on the other side of the generator 4. The centrifugal clutch 10 includes an outer case 11 attached to the crankcase 3 and a crankcase 3. It is located in the room 12 to be formed.

The clutch outer 13 of the centrifugal clutch 10 is connected to a clutch gear 14 loosely fitted on the intermediate rotation shaft 6,
It is rotated integrally with 14. A clutch center 15 is arranged inside the clutch outer 13, and the clutch center 15 is spline-engaged on the intermediate rotary shaft 6 via an annular support 16. The clutch plate 18 is attached to
Is engaged so as to be movable in the axial direction, and the clutch plate 18 is engaged with the clutch outer 13 so as to be movable in the axial direction.
Are arranged so as to slide in contact with each other. Inside the clutch center 15, a plurality of support columns 19 are fixed with bolts 20,
The support portion 21a of the support cover 21 is inserted through the support pillar 19, and the buffer spring 23 is provided between the stopper 22 and the support portion 21a of the support pillar 19.
Is provided. A pressure plate 24 is locked on a shaft portion 21b formed at the center of the support cover 21 and is prevented from coming off by a stopper 25. Pressure plate 24
Is a return spring 26 which is supported by being inserted into a boss portion 15a formed integrally with the clutch center 15 and which is inserted and attached to the boss portion 15a.
Is biased toward the support cover 21.

Actuator formed on the outer periphery of the pressure plate 24
24a is interposed between the clutch plates 17 and 18 and the centrifugal weight 27. The centrifugal weight 27 rolls on the cam 21c of the support cover 21 by a centrifugal force and pushes the pressure plate 24 against the return spring 26, thereby engaging and disengaging the clutch plates 17 and 18.
Lubricating oil is supplied to the inside of the centrifugal clutch 10 from a passage 28 formed in the intermediate rotary shaft 6, and the lubricating oil is centrifugally generated by the rotation of the clutch center 15 to pass from the passage 15b to the clutch plates 17 and 18.
Supplied to the side.

A transmission shaft 29 is rotatably supported by the crankcase 3, and the clutch gear 14 meshes with an input gear 30 formed integrally with the transmission shaft 29. Clutch gear 14 and input gear 30
The deceleration mechanism consisting of is located near the crankcase 3 outside the crankcase 3. In this way, the speed increasing mechanism and the speed reducing mechanism are arranged in the vicinity of the inside and outside of the crankcase 3 with the crankcase 3 interposed therebetween. One end of the transmission shaft 29 is spline-engaged with an input shaft 32 of a toroidal continuously variable transmission 31, and both ends of the input shaft 32 are supported by a casing 35 via bearings 33 and 34, respectively. The clutch carrier 14 of the reduction mechanism has a smaller diameter than the clutch plate 17 of the automatic starting centrifugal clutch 10.

In the known toroidal type continuously variable transmission 31, a cam plate 36 is integrally rotatably connected to one end of the input shaft 32,
Power is transmitted from the cam plate 36 to the input disk 38 via the rollers 37. The input disc 38 is loosely fitted on the input shaft 32, the output disc 39 is arranged so as to face the input disc 38, and the output disc 39 is also loosely fitted on the input shaft 32. Rotating curved surfaces 38a, 39a are formed on the input disk 38 and the output disk 39 so as to face each other, and a pair of power rollers 40 are arranged so as to contact each other between the rotating curved surfaces 38a, 39a. The power from the input disk 38 is the power roller 40
Is transmitted to the output disc 39 via. Power roller 40
Are rotatably supported by trunnions 41, respectively, and the power roller 40 is tilted while rotating between the input disk 38 and the output disk 39, so that there is no step between the input disk 38 and the output disk 39. The gear ratio is obtained. The trunnion 41 is supported by the caging 35 via a support mechanism (not shown), and by moving this support mechanism in the axial direction,
The power roller 40 is inclined. As shown, when the power roller 40 is positioned parallel to the input shaft 32, the input disc 38 and the output disc 39 rotate at the same speed. When the shaft center is tilted about the shaft center position of the power roller 40, the speed is increased or decreased. Trunnion 41 not shown
By the axial movement of the actuating mechanism, the well-known automatic speed change action occurs, and a desired speed change ratio is obtained.

An output gear 42 is fixed to the shaft portion of the output disk 39, and the output gear 42 meshes with a gear 44 on the output shaft 43. Output gear 42
A one-way clutch 45 is installed between the shank and the casing 35.
Is provided to prevent the output gear 42 from rotating in the reverse direction.

The output shaft 43 is rotatably supported by the crankcase 3, and a switching dock 46 is provided on one end of the output shaft 43 so as to be movable in the axial direction. Gear 44 and output shaft by switching dock 46
When power is switched to and from 43, and when it is desired to move backward, the switching dock 46 cuts off power transmission between the gear 44 and the output shaft 43 to allow the output shaft 43 to rotate in the reverse direction.

A bevel gear 47 is spline-engaged with the other end of the output shaft 43, and the bevel gear 47 is meshed with a bevel gear 48 pivotally supported by the crankcase 3. The drive shaft is attached to the shaft of the bevel gear 48.
49 is spline-engaged, and the drive shaft 49 is connected to a drive system via a universal joint 50.

Next, the operation of this embodiment will be described.

The power of the internal combustion engine 1 is from the crankshaft 2 to the crank gear 5
Is transmitted to the intermediate rotary shaft 6 after being accelerated by the gear speed increasing mechanism of the crank gear 5 and the input gear 7. The intermediate rotary shaft 6 rotates in synchronization with the crankshaft 2 at a predetermined ratio,
The intermediate rotary shaft 6 rotates faster than the crankshaft 2. The vibrations of the internal combustion engine 1 that cannot be canceled by the crankshaft 2 are canceled by the balancers 8 and 9 on the crankshaft 2 that rotates at high speed, and the ride comfort of the vehicle can be made comfortable.

The rotation of the intermediate rotary shaft 6 rotates the clutch center 15 of the centrifugal clutch 10, and the pressure plate 24 and the support cover 21 rotate together with the clutch center 15. When the rotation speed of the internal combustion engine 1 is less than or equal to a predetermined value, the centrifugal force acting on the centrifugal weight 27 is small, so the centrifugal weight 27 is located inside the cam 21c, and the pressure plate 24 causes the return spring 26 to move.
Thus, the clutch plates 17 and 18 are held in a non-pushed state. Therefore, the clutch connection of the centrifugal clutch 10 is not performed.

Then, when the internal combustion engine 1 reaches a predetermined rotational speed or higher, the centrifugal weight 27 rolls on the cam 21c by the action of centrifugal force and moves outward, and pushes the pressure plate 24. Therefore, the clutch plates 17 and 18 are pushed in the axial direction by the pressure plate 24 to make sliding contact, and the clutch of the centrifugal clutch 10 is connected. The input side of the centrifugal clutch 10 is connected to the intermediate rotary shaft 6, and the intermediate rotary shaft 6 is connected to the crank gear 5 as described above.
Since the speed is increased by the gear speed increasing mechanism of the input gear 7, the centrifugal weight 27 rolls faster and the starting response is better than before. By connecting the clutch of the centrifugal clutch 10, the power of the internal combustion engine 1 is transmitted from the clutch outer 13 of the centrifugal clutch 10 to the clutch gear 14, and the clutch gear 14 and the transmission shaft 29.
Is reduced by the gear mechanism of the input gear 30 and input to the toroidal continuously variable transmission 31. As described above, the speed is increased by the gear speed increasing mechanism of the crank gear 5 and the input gear 7, but the speed increased here is increased by the clutch gear 14 and the input gear 30.
When the gear reduction mechanism is used to reduce the speed, the rotational speeds of the transmission shaft 29 and the crankshaft 2 become the same as in the conventional example.

In the toroidal type continuously variable transmission 31, the trunnion 41 is supported by the caging 35 via a support mechanism (not shown), and the power roller 40 is moved by axially moving the support mechanism.
A known automatic speed change action occurs between the input disk 38 and the output disk 39 to obtain a desired speed change ratio. This changed power is generated when the switching dock 46 is engaged with the gear 44.
It is transmitted from the output gear 42 to the gear 44 and the output shaft 43, and is transmitted to the drive system via the bevel gears 47 and 48 and the drive shaft 49.

Thus, the intermediate rotary shaft 6 operates as a balancer shaft that rotates in synchronization with the crankshaft 2 at a predetermined ratio, and also functions as a power transmission shaft that transmits the power of the internal combustion engine 1 to the centrifugal clutch 10. Therefore, the intermediate rotary shaft 6 shares the power transmission shaft for transmitting the power of the internal combustion engine 1 and the balancer shaft, and the weight of the shaft rotatably supported by the crankcase 3 is reduced accordingly.

In this embodiment, the power of the internal combustion engine 1 is input to the automatic starting clutch via the intermediate rotation shaft, but the power of the internal combustion engine 1 is input to the continuously variable transmission via the intermediate rotation shaft to continuously change the speed. The same can be applied to the case where the transmission is transmitted to the drive system via the automatic starting clutch.

〔The invention's effect〕

According to the present invention, the speed increasing mechanism and the intermediate rotary shaft are provided between the crankshaft and the centrifugal clutch for automatic start, and the balancer is arranged at a position on the intermediate rotary shaft between the pair of crank webs of the crankshaft. did. Therefore, power is transmitted from the crankshaft to the automatic starting centrifugal clutch via the intermediate rotation shaft,
The balancer shaft and the power transmission shaft are shared by the intermediate rotary shaft, and the shared weight can reduce the weight of the shaft, which makes it easy to secure a mounting space and simplifies the configuration. Since the balancer is arranged at a position facing each other between the pair of crank webs of the crank shaft, the axial distance between the crank shaft and the intermediate rotary shaft can be shortened,
The power transmission device can be downsized.

Moreover, due to the existence of the speed increasing mechanism, the intermediate rotating shaft and the centrifugal weight of the automatic starting centrifugal clutch are accelerated and rotated. Therefore, the function of the balancer of the intermediate rotation shaft is sufficiently exerted, and the responsiveness of the automatic starting centrifugal clutch is good. And
Depending on the degree of acceleration, even if the balancer of the intermediate rotating shaft and the centrifugal weight of the automatic starting centrifugal clutch are downsized, the necessary functions as the balancer and the centrifugal weight can be exhibited.

In the present invention, since the speed reducing mechanism is interposed between the automatic starting centrifugal clutch and the transmission, the speed increasing mechanism can cancel the speed increase by the speed reducing mechanism. Therefore, the conventional gear ratio of the drive system of the vehicle can be applied.

Further, according to the present invention, the speed increasing mechanism and the speed reducing mechanism are arranged in the vicinity of the inside and outside of the crankcase with the crankcase sandwiched therebetween. Therefore, the gears that form the speed increasing mechanism and the speed reducing mechanism are supported in the vicinity of the crankcase, and the load on the shaft that supports the gear during meshing is small, so the weight of the supporting shaft is reduced and the weight is reduced. You can

Further, in the present invention, the generator is arranged at one end of the crankshaft, and the automatic starting centrifugal clutch is arranged at the other end of the intermediate rotating shaft on the other side of the generator. A reduction gear mechanism consisting of a clutch gear having a diameter smaller than that of the clutch plate is installed. In this way, the generator and the automatic starting centrifugal clutch are arranged on opposite sides of the crankcase, and the speed reducing mechanism is composed of a clutch gear having a smaller diameter than the clutch plate of the automatic starting centrifugal clutch. The distance between the intermediate rotation shaft and the transmission shaft is shortened, and the power transmission device can be downsized.

[Brief description of drawings]

 FIG. 1 is a sectional view of a power transmission device to which the present invention is applied. 1 …… Internal combustion engine 2 …… Crankshaft 3 …… Crankcase 5 …… Crank gear 6 …… Intermediate rotary shaft 7 …… Input gear 8,9 …… Balancer 10 …… Centrifugal clutch 14 …… Clutch gear 30 …… Input gear 31 ... Toroidal type continuously variable transmission

Claims (1)

[Claims] 1. A power transmission device for a vehicle, comprising a centrifugal clutch for automatic start and a transmission between a crankshaft of an internal combustion engine and a drive system, wherein an increase in speed is provided between the crankshaft and the centrifugal clutch for automatic start. A mechanism and an intermediate rotating shaft are interposed, and a balancer is arranged on the intermediate rotating shaft at a position facing each other between a pair of crank webs of the crankshaft, and the automatic starting is performed between the centrifugal clutch for automatic starting and the transmission. The speed reduction mechanism consisting of a clutch gear having a diameter smaller than that of the clutch plate of the centrifugal clutch for use is interposed, and the speed increasing mechanism and the speed reducing mechanism are respectively arranged in the vicinity of the inside and outside of the crankcase with the crankcase sandwiched therebetween. A power transmission device for a vehicle, characterized in that a generator is disposed on the other side, and a centrifugal clutch for automatic starting is disposed on the other side of the intermediate rotating shaft on the other side of the generator.