JPH0488247A - Damper device for primary driven gear - Google Patents

Abstract

PURPOSE:To reduce the generation of gear noise and absorb the impact force due to kick at engine start by connecting the gear body of a primary driven gear and a clutch housing with a back plate through a damper mechanism. CONSTITUTION:A damper mechanism is constituted of a damper rubber 38 and a damper spring 39. The damper rubber 38 is installed on a pin 29. The pin 29 connects a cover plate 26 and a clutch housing 28, and is fitted in a through hole 40 opened on the gear body 27 of a primary driven gear 24, in a state where the damper rubber 38 is fitted. Further, a through hale 41 is opened on the gear body 27 of the primary driven gear 24. Recessed parts 42 and 43 are formed on the clutch housing 28 and a cover plate 26 so as to surround both the sides of the through hole 41. Then, a coil-shaped damper spring 39 is accommodated in the through hole 41 and recessed parts 42 and 43.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a damper device for a primary drive gear that can reduce both the impact when a friction clutch is engaged and the impact when a kick start is performed.

(Prior art) In the power transmission system of motorcycles, etc., a friction clutch that can be controlled to open and close is interposed between the crankshaft and the countershaft.
It is designed to control the transmission torque when starting or shifting gears. Such friction clutches are often mounted on the end of a counter shaft as shown in FIG.

A primary driven gear 2 is rotatably supported at the end of the countershaft 1, and is engaged with a primary drive gear 3 on the crankshaft to transmit rotation. A clutch housing 4 is coupled to this primary driven gear 2 via a pin 5 and a damper mechanism, and rotation from the primary driven gear 2 is transmitted thereto.

The damper mechanism includes a damper rubber 6 attached to a pin 5, a damper spring 7 interposed between the primary driven gear 2 and the clutch housing 4, and a clutch sleeve 8 fixed to the counter shaft 1. ,
A plurality of driven friction plates 9 are stacked on the clutch sleeve 8 and the clutch housing 4.
and a drive friction plate 10, respectively. In normal conditions, the drive friction plate 10 and the driven friction plate 9 are pressed by the pressure plate 11, the clutch housing 4 and the clutch sleeve 8 are connected, and torque is transmitted from the crankshaft to the countershaft 1.

Now, a kick driven gear 12 is integrally formed in the boss portion of the primary driven gear 2 in the first conventional example as described above. This kick driven gear 12 is meshed with a kick drive gear 14 via a kick idle gear 13. Therefore, the kick force that acts when starting the engine is transmitted from the kick drive gear 14 to the kick driven gear 12 via the kick idle gear 13,
The signal is transmitted from primary driven gear 2 to primary drive gear 3, thereby rotating the crankshaft and starting the engine.

Further, in the second conventional example shown in FIG. 3, a kick driven gear 15 is rotatably supported on a counter shaft, and a clutch housing 16 is connected to a boss portion of the kick driven gear 15 by a spline. Further, the primary driven gear 17 is placed on the stepped portion of the clutch housing 16 and is fixed to the clutch housing 16 by a pin 18 .

A damper mechanism including a damper rubber 19 and a damper spring 20 is also arranged between the primary driven gear 17 and the clutch housing 16.

This damper mechanism absorbs and alleviates the impact force when the torque transmitted from the primary drive gear to the primary driven gear 17 is transmitted to the clutch housing 16 when the friction clutch is engaged.

Further, the damper mechanism is configured such that the kick force transmitted from the kick driven gear 15 to the clutch housing 16 at the time of kick start is transmitted to the primary driven gear 17 via the damper mechanism. absorb and relieve.

Note that the kick force is transmitted to the primary driven gear 17 and then to the primary drive gear to rotate the crankshaft.

(Problems to be Solved by the Invention) In the first conventional example shown in FIG. 2, since there is no damper mechanism in the kick force transmission system, it is not possible to alleviate the impact force at the time of kick start. For this reason, kick driven gear 12,
Kick idle gear 13 and kick drive gear 14
It is necessary to widen the gear width and increase the strength of the gear.

Further, in the second conventional example shown in FIG. 3, since a damper mechanism (damper rubber 19 and damper spring 20) is present in the kick force transmission system, the kick driven gear 15,
The width of the kick idle gear and kick drive gear can be made thinner.

However, since the primary driven gear 17 is mounted on the clutch housing 16 which is spline-coupled to the kick driven gear 15, the primary driven gear 17
There is a possibility that the misalignment of 7 may become large. Therefore, when the primary driven gear 17 and the primary drive gear mesh, gear noise may occur.

This invention was made in consideration of the above circumstances,
It is an object of the present invention to provide a damper device for a primary driven gear that can reduce the generation of gear noise of a primary gear and can absorb impact force when starting an engine due to a kick.

[Structure of the invention]

(Means for Solving the Problems) In the present invention, a kick driven gear is rotatably disposed on a counter shaft, a back plate of a primary driven gear is fixed to a boss portion of the kick driven gear, and a back plate of a primary driven gear is fixed to a boss portion of the kick driven gear. The gear body of the primary driven gear is placed adjacent to the back plate, and the gear body and clutch housing of the primary driven gear are connected to the back plate via a damper mechanism. be.

(Function) Therefore, according to the damper device for the primary driven gear according to the present invention, the kick force is transmitted to the kick driven gear, and then transmitted from the back plate of the primary driven gear to the gear body of the primary driven gear via the damper mechanism. is transmitted to the crankshaft via a primary drive gear that meshes with the gear body of this primary driven gear. In this way, since the damper mechanism is present in the kick force transmission path, the impact force at the time of kick start can be alleviated.

In addition, since the gear body of the primary driven gear is placed directly on the boss of the kick driven gear, it is possible to reduce the misalignment of the primary driven gear, and the generation of gear noise when the primary drive gear meshes with the primary driven gear. can be suppressed.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a longitudinal sectional view of a motorcycle power transmission system showing an embodiment of a damper device for a primary drive gear according to the present invention.

A kick driven gear 22 is rotatably mounted on an end of the counter shaft 21. A back plate 25 of the primary driven gear 24 is integrally formed with the boss portion 23 of the kick driven gear 22, or is fixed integrally with the boss portion 23 by welding or the like. A cover plate 26 is welded to the outer periphery of this back plate 25. The gear main body 27 of the primary driven gear 24 is placed on the boss portion 23 of the kick driven gear 22 and is disposed adjacent to the back plate 25.

A clutch spring 28 is arranged outside this gear body 27. These cover plate 26, gear body 27
and a clutch housing 28 are integrally connected by a pin 29 and a damper mechanism to be described later.

The gear body 27 of the primary driven gear 24 is engaged with the primary drive gear 30 on the crankshaft, and rotation is transmitted thereto. Further, a plurality of drive friction plates 31 are held on the inner periphery of the clutch housing 28 so as to be slidable in the axial direction. On the other hand, a clutch sleeve 32 is fixed to the tip of the counter shaft 21.
A plurality of driven friction plates 33 are held on the outer periphery of 2 so as to be slidable in the axial direction. The drive friction plates 31 and the driven friction plates 33 are arranged alternately one on top of the other.

A pressure plate 34 is stacked on the outside of the drive friction plate 31 and the driven friction plate 33 in the vertical and horizontal directions, and this pressure plate 34 and the clutch sleeve 3
A clutch spring 35 is mounted between the clutch spring 2 and the clutch spring 35. Under normal conditions, due to the biasing force of the clutch spring 35,
Pressure plate 34 connects both friction plates 31 and 3
3 inward, the clutch housing 28 and clutch sleeve 32 are connected, and the countershaft 2 is moved from the crankshaft.
1 hetorque is transmitted.

Reference numeral 36 denotes a release rack, which is attached to the pressure plate 34 via a thrust bearing 37 so as to be relatively rotatable. This release rack 36 is connected to a release mechanism including a release pinion. By the operation of this release mechanism, the release rack 36 moves the pressure plate 34 against the biasing force of the clutch spring 35, breaks contact between both friction plates 31 and 33, and transfers the rotational force from the crankshaft to the countershaft. Cut off transmission.

Now, the damper mechanism described above includes a damper rubber 38 and a damper spring 39.

The damper rubber 38 is attached to the pin 29. This pin 29
The cover plate 26 and the clutch housing 28 are connected together, and the damper rubber 38 is fitted into the through hole 40 opened in the gear body 27 of the primary driven gear 24.

Further, a through hole 41 is further opened in the gear body 27 of the primary driven gear 34. Recesses 42 and 43 are formed in clutch housing 28 and cover plate 26 to surround both sides of through hole 41, respectively. A coiled damper spring 39 is accommodated within these through holes 41 and recesses 42 and 43. This damper spring 39 is arranged with its axis in the circumferential direction of the primary driven gear 24, and the coil spring 39
One end contacts one end of the through hole 41, and the other end of the coil spring 39 contacts the other ends of the recesses 42 and 43 in the rotational direction.

In this way, the rotation transmitted from the primary drive gear 30 to the gear body 27 of the primary driven gear 24 is transmitted to the clutch housing 29 after the impact force is absorbed and alleviated by the damper rubber 38 and the damper spring 29.

Therefore, the damper rubber 38 and the damper spring 39 can reduce the impact when the friction clutch is engaged.

Further, the kick driven gear 22 is engaged with a kick drive gear 45 via a kick idle gear 44.

Therefore, when kick starting the engine, the kick force is transmitted from the kick drive gear 45 to the kick idle gear 44 to the kick driven gear 22. This kick force is transmitted from the kick driven gear 22 to the gear body 27 of the primary driven gear 24 via the back plate 25 and cover plate 26, the damper rubber 38 and the damper spring 39, and then transmitted to the crankshaft via the primary drive gear 30. It will be done.

As described above, since the damper rubber 38 and the damper spring 39 are present in the kick force transmission path, the impact force at the time of kick starting the engine can be alleviated by the damper rubber 38 and the damper spring 39.

Furthermore, since the gear body 27 of the primary driven gear 24 is placed on the boss portion 23 of the kick driven gear 22, misalignment of the gear body 27 can be reduced. As a result,
It is possible to suppress the generation of gear noise when the gear body 27 of the primary driven gear 24 and the primary drive gear 30 mesh with each other.

〔Effect of the invention〕

As described above, according to the primary driven gear damper device according to the present invention, the back plate of the primary driven gear is fixed to the boss portion of the kick driven gear rotatably disposed on the counter shaft, and the back plate of the primary driven gear is fixed to the boss portion of the kick driven gear rotatably disposed on the counter shaft. The gear body of the primary driven gear is placed adjacent to the back plate in the part, and the gear body and clutch housing of the primary driven gear are connected to the back plate via a damper mechanism.
It is possible to reduce the gear noise generated by the primary gear, and also to reduce the impact force at the time of kick-starting the engine.

A, 25... Back plate, 27... Gear body,
28...Clutch housing, 30...Primary drive gear, 38...Damper rubber, 39...Damper spring, 40.41...Through hole, 42.43...
- Recessed portion, 44...Kick idle gear, 45...Kick drive gear.

Claims (1)

[Claims] A kick driven gear is rotatably disposed on the counter shaft, a back plate of the primary driven gear is fixed to a boss part of the kick driven gear, and a gear body of the primary driven gear is attached to the boss part of the back plate. A damper device for a primary driven gear, characterized in that the gear body and clutch housing of the primary driven gear are placed adjacent to each other and are connected to the back plate via a damper mechanism.