JPS62137443A - Gear wheel with damper - Google Patents

Abstract

PURPOSE:To enable cushioning without reducing the engagement accuracy by providing a toothed wheel loose-fittedly supported on a supporting shaft and a boss part fixed on the supporting shaft so as to be adjacent, and combining the space between a ring-shaped outer ring projectedly formed from the side of the toothed wheel and the outer surface of the boss part with a damper rubber. CONSTITUTION:In a reduction gear 6d, the space between the boss part B press-fitted on an output shaft 6b and a toothed wheel R is combined with a baked rubberlike elastic body E. An end plate 63 extending from the end of the toothed wheel R toward inside prevents the shaft center of the toothed wheel R and that of the boss part B from becoming eccentric by a transmission force. A restricting device 8 is made up of recesses 64 on the end plate 63 and projections 65 on the boss part B, and it is so arranged that each of the recesses 64 and the projections 65 when assembled has clearances 66 on both sides. Accordingly, when the deformation of the elastic body E during power transmission is within the range of the clearances 66, the restriction is not caused, and when the deformation of the elastic body E becomes large enough, the projections 65 are brought into contact with the inner walls of the recesses 64 to prevent further turning, and the sudden change in the driving force acting on a rearwheel driving system can be relieved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention mainly relates to a gear with a damper that is suitable as a gear for scooters and other small vehicles.

[Conventional technology and its problems]

Conventionally, the applicant has already proposed a gear with a damper in which the gear and the boss are manufactured separately and integrated by coupling them with damper rubber.

However, when a damper rubber made of rubber is interposed between the gear and the boss, the damper rubber is deformed by the pushing force due to the pressure angle of the gear and the tension of the chain.
Since the gears may be eccentric, they may not be suitable for precision gear mechanisms.

[Object of the invention, outline of the structure]

The purpose of this invention is to solve the above-mentioned problems and to obtain a gear with a damper that can perform cushioning power transmission while maintaining precise meshing accuracy. In the case where the tooth ring loosely supported on the spindle and the boss portion locked on the spindle are arranged adjacent to each other, the tooth ring and the boss portion protrude outward from the side of the tooth ring. The provided annular outer ring and the outer surface of the boss are connected by damper rubber.

[Effect]

Since the tooth ring is loosely supported directly on the support shaft, the fitting accuracy does not decrease and is damped by the damper rubber provided adjacently.

〔Example〕

Hereinafter, the present invention will be explained with reference to the illustrated embodiment. In the figure, numeral 1 is a so-called unit swing type dynamic crab knit in which the engine, transmission case, and rear wheel of a scooter S are integrally constructed. In the dynamic crab knit 1, a crankshaft 3, which is an output shaft of an engine, is attached to the front part of a case 2, and a rear axle 5, which supports a rear wheel 4, is supported at the rear part. 6 is a reduction gear mechanism disposed between the crankshaft 3 and the rear axle 5.

The reduction gear mechanism 6 includes a pair of reduction gears 6c and 6d provided on an input shaft 6a and an output shaft 6b. Input shaft 6&
and the crankshaft 3 is a primary transmission D including a chain T.
1, and the output shaft 6b and rear axle 5 are connected by a secondary transmission D2 consisting of a pair of meshing gears 6e and 5a. These human power transmission D1 and secondary power transmission D2 are constructed by separating at least one of the gears that constitute them into a gear R and a boss B, and connecting them with a rubber-like elastic body E. It consists of a buffer gear G.

In the following description, the gear R, the boss B, the rubber-like elastic body E, and the buffer gear G will be described with common reference numerals assigned to a plurality of gears having similar functions.

First, the one-break transmission D1 with many buffer gears G will be explained.

The chain 7 is wound between a driving chain gear 32 provided on the output side of a centrifugal clutch 31 installed at the end of the crankshaft 3 and a driven chain gear 610 provided on the input shaft 6a. Here, the drive chain gear 32 includes a boss B welded to the output side 33 of the centrifugal clutch 31, a tooth R loosely fitted onto the boss B, and a cylindrical protrusion extending laterally from the tooth R. Part 34
and a rubber-like elastic body E baked on the inner surface of the large diameter portion 35 of the boss portion B, and some axial displacement fF is tolerated between the gear ring R and the boss portion B. As a result, the rotational impact acting on the drive chain gear 32 can be alleviated. still,
The driven chain gear 61 is composed of a boss part B press-fitted into the input shaft 6a and a tooth ring R located outside the boss part B, and a rubber-like elastic body E is similarly baked between them. ing. 6
Reference numeral 2 denotes an end plate extending inward from the end of the tooth ring R, and prevents the axis of the tooth ring R from being excessively eccentric from the axis of the boss portion B due to transmission force. In this way, the power transmission D1 can alleviate not only the torque fluctuations output from the crankshaft 3 but also the sudden fluctuations in the driving force acting on the rear wheel drive system as the centrifugal clutch 31 is engaged and disengaged.

In the reduction gear mechanism 6, the reduction gear 6d fixedly installed on the output shaft 6b serves as a buffer gear G.

That is, the reduction gear 6d is made of a rubber-like elastic body E that is baked between the boss portion B press-fitted onto the output shaft 6b and the gear R.
It is connected with. Reference numeral 63 denotes an end plate extending inward from the end of the gear R, which prevents the axis of the gear R from being excessively eccentric from the axis of the boss B due to the transmission force, and also prevents the axis of the gear R from being excessively eccentric from the axis of the boss B. constitutes a part.

That is, as shown in FIGS. 3 and 4, the restriction device 8 is provided between the boss portion B and the end plate 63, and is located in four recesses 64 formed on the inner peripheral surface of the end plate 63. and four protrusions 65 protruding from the outer surface of the boss part B.
4 and the protrusion 65 are provided with gaps 66 and 66 on both sides.

Therefore, during power transmission, while the rubber-like elastic body E is deformed within the range of this gap 66, the same restriction is not applied, but the rubber-like elastic body E is greatly deformed and the boss portion B and the tooth ring If there is a large deviation in the rotational direction between R and R,
The four protrusions 65 abut against the inner wall of the recess 64 to prevent further rotation.

[Effects of the Invention] As described above, the present invention integrally connects the tooth ring and the boss portion via the damper rubber, and the tooth ring and the boss portion are loosely supported on the support shaft and the boss portion is secured to the support shaft. The outer surface of the boss is connected to the annular outer ring that protrudes from the side of the gear to the outside of the boss with a damper rubber. Since it is directly supported loosely, eccentricity does not occur, and since it is buffered by the adjacent damper rubber, the original purpose can be achieved.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a side view of the scooter, FIG. 2 is its If-Ilt drawing, and FIG. 3 is an enlarged cross-sectional view of its main parts. It is a diagram. 1...Moving crab knit, G...Buffer gear, B...
...Boss part, R...Gear ring, E...Rubber-like elastic body, 8...Restriction device, Dl...-human power transmission, Dl...Nikyu power transmission . Patent applicant: Yamaha 1JlJ Machine Co., Ltd. Agent: Masatsuna Yamakawa (eυ, 2 people) Figure 1 Figure 3

Claims (4)

[Claims] (1) In a device that integrally connects a tooth ring and a boss part via a damper rubber, the tooth ring loosely supported on a support shaft and the boss part locked to the support shaft are arranged adjacent to each other. A gear with a damper, in which a damper rubber connects an annular outer ring protruding from the side of the gear ring to the outside of the boss and the outer surface of the boss. (2) A gear with a damper according to claim 1, wherein the gear is a meshing gear. (3) The gear with a damper according to claim 1, wherein the gear is a chain gear. (4) The gear with a damper according to claim 1, wherein the gear is loosely supported on the outer surface of the support cylinder extending from the boss portion.