JPS6027251Y2 - Gear rattling prevention device in gear transmission - Google Patents

Description

[Detailed Description of the Invention] This invention relates primarily to gear transmissions for automobiles, and particularly to a device for preventing rattling due to backlash in a reverse gear system.

Since a reverse gear system requires an extra idler gear compared to other gear systems, it is difficult to adjust backlash when a constant mesh type is adopted.

As a result, rattling noise is likely to occur in the range of reverse gear rattling in low speed rotation ranges such as idling.

Various means have been conventionally provided as countermeasures against this problem.

However, none of these methods has been able to effectively suppress gear rattling, and it has been found that unnecessary resistance is added to the rotation of the reverse gear during normal torque transmission (high-speed rotation range), and excessive friction is caused by excessive friction. This includes problems such as causing abnormal heat generation.

In consideration of these conventional problems, this invention effectively provides drag resistance to the reverse gear in low-speed rotation ranges such as idling, and eliminates unnecessary friction and resistance in high-speed rotation ranges. The object of the present invention is to provide a device for preventing rattling of a bark-covered gear.

Next, the configuration of this invention will be explained in detail according to an embodiment shown in the drawings.

FIG. 1 shows a clutch portion of a constant mesh type reverse gear system in an automobile transmission.

In this drawing, a reverse gear 2 is mounted on the output shaft 1 of the transmission, and a needle roller bearing 3 is mounted on the output shaft 1 of the transmission.
It is rotatably supported by.

This reverse gear 2 meshes with a counter gear (not shown) so that torque can be transmitted through an idler gear.

On the other hand, a clutch bub 6 is provided on the output shaft 1 so as to rotate integrally with the shaft 1.

A clutch hub sleeve 9 is provided on the outer periphery of the clutch bub 6 so as to be slidable in the axial direction.

That is, 1. By sliding the clutch hub sleeve 9 and engaging it with the spline 4 of the reverse gear 2, the rotation of the reverse gear 2 can be transmitted to the output shaft 1.

In FIG. 1, reference numeral 10 indicates a shifting key, and 11 indicates a key spring.

Now, in the clutch hub 6 described above, the reverse gear 2
A cone surface 8 is formed on the outer periphery of the boss portion 7 on the side opposite to.

On this cone surface, as also shown in FIGS. 2 and 3, a friction member 12 having a friction surface 13 corresponding to and in contact with the cone surface 8 is disposed.

Furthermore, this friction member 12 is integrally formed with a round bar-shaped engagement part 14, which engages with a slit 5 formed in a part of a cylindrical protrusion 17 of the reverse gear 2. There is.

Further, a spring 15 is interposed between the counterbore portion 16 of the friction member 12 formed around the axis of the retaining portion 14 and the inner surface of the protruding portion 17 of the reverse gear 2.

With these configurations, the friction member 12 is connected to the reverse gear 2
The friction surface 13 is pressed against the cone surface 8 by the elasticity of the spring 15.

As is clear from FIG. 2, the friction surface 13 of the friction member 12 is formed with fine grooves for draining oil.

Further, a plurality of (for example, three) friction members 12 are arranged in the circumferential direction of the cone surface 8.

According to the above configuration, when the reverse gear 2 is rotating at a low speed, the friction member 12 rotating together with the reverse gear 2 is pressed against the cone surface 8 of the clutch hub 6 as described above. This provides drag resistance (braking force) to the reverse gear 2.

Therefore, rattling due to backlash between the reverse gear 2, the idler gear, and the counter gear is prevented.

Then, when the rotation of the reverse gear 2 reaches a high speed rotation range, the friction member 12 resists the elasticity of the spring 15 due to its centrifugal force, and the cone surface of the clutch hub 6
It will be in a state where it is floating.

As a result, the above-mentioned dragging resistance acting on the reverse gear 2 is released.

As described above, the present invention forms a cone surface on the outer periphery of the boss portion of the clutch hub fixed to the output shaft in the gear transmission, while forming a cone surface of the boss portion in the inner peripheral wall space of the clutch hub. A friction member having a correspondingly shaped friction surface is disposed so as to be prevented from rotating on a reverse gear which is rotatably attached to the output shaft, and this friction surface is provided with fine grooves for draining oil. At the same time, the friction member presses its friction surface against the cone surface by a spring force, and the elastic force of the spring is applied to the cone surface by the centrifugal force acting on the friction member in the high speed rotation range of the reverse gear. By setting it away from the surface, when the reverse gear is in a low rotational speed range, the friction surface of the friction member receiving the spring force is pressed against the cone surface of the boss part of the clutch hub, and the reverse gear is rotated. It is possible to provide drag resistance to the gear, thereby suppressing rattling of the reverse gear during idling, for example.

Moreover, when the reverse gear is in a high-speed rotation range, the centrifugal force acting on the friction member at this time cancels the drag resistance against the reverse gear, causing unnecessary load and accompanying horsepower loss during normal driving of the vehicle. can be avoided.

In particular, the present invention arranges the friction member in the inner peripheral surface space of the clutch hub, so that the presence of the friction member does not sacrifice space in the axial direction of the output shaft, and the transmission case can be made large. In addition, since the friction surface of the friction member is formed with a groove for draining oil, the friction force between this friction surface and the cone surface of the boss portion is increased, and The drag resistance against the reverse gear can be effectively exerted, and the shape and number of the oil draining grooves can be changed.

Furthermore, the drag resistance to the reverse gear described above utilizes the frictional force on the outer periphery of the boss portion of the clutch hub, which has a relatively large rotation radius, on the output shaft. It can be efficiently exerted as drag resistance against the reverse gear.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention; FIG. 1 is a sectional view showing a part of a reverse gear system in a transmission, FIG. 2 is an enlarged sectional view within a circle surrounded by an imaginary line in FIG. 1, Figure 3 is the first
It is a sectional view taken along the line ■-■ in the figure. 1 Near-end shaft, 2: Reverse gear, 5 Ni-slit, 6: Clutch hub, 7: Boss portion, 8: Cone surface, 12: Friction member, 14: Engagement portion, 15 Spring.

Claims (1)

[Scope of utility model registration request] A cone surface is formed on the outer periphery of the boss portion of the clutch hub fixed to the output shaft in the gear transmission, while a friction surface having a shape corresponding to the cone surface of the boss portion is formed in the inner circumferential space of the Clara hub. the friction member is arranged in a state where it is prevented from rotating by a reverse gear rotatably provided with respect to the output shaft,
A fine groove for draining oil is formed on this friction surface, and the friction member uses a spring force to press the friction surface against the cone surface. A device for preventing gear rattling in a gear transmission, characterized in that the member is set so as to be separated from the cone surface by centrifugal force acting on the member.