JP2023169509A - gear - Google Patents

Abstract

To provide a gear capable of suppressing noise.SOLUTION: A damper 300 is equipped with a first cylindrical member 310 to be fitted with an inner peripheral surface of an outer ring 100, a second cylindrical member 320 to be fitted with an outer peripheral surface of an inner ring 200, and a plurality of elastic shock absorbers 330 to be fixed to an inner peripheral surface of the first cylindrical member 310 and an outer peripheral surface of the second cylindrical member 320. At an end portion of a cylinder portion 311 in the first cylindrical member 310, an outward flange portion 312 provided so as to face an end surface of the outer ring 100 is provided. Between the end surface of the outer ring 100 and the outward flange portion 312, an elastic body 332 is sandwiched while being compressed.SELECTED DRAWING: Figure 3

Description

The present invention relates to gears.

For example, a technique is known in which a shock absorbing elastic body is provided in a gear provided in a drive unit of an automobile in order to suppress noise. That is, a technique is known in which a gear includes an outer ring, an inner ring, and an annular elastic body provided between the outer ring and the inner ring. However, although this technology has the effect of reducing abnormal noise by reducing vibrations caused by rotational fluctuations, it has not been able to sufficiently suppress high-frequency abnormal noise caused by the meshing of teeth (gears). There is room for improvement.

Japanese Patent Application Publication No. 4-362346

The present invention provides a gear that can suppress noise.

The present invention employs the following means to solve the above problems.

That is, the gear of the present invention is
an outer ring having multiple teeth on the outer periphery;
an inner ring disposed concentrically inside the outer ring;
an annular damper disposed between the outer ring and the inner ring;
Equipped with
The gear is provided with a rotation preventing structure that limits relative rotation between the outer ring and the inner ring within a certain range between the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring,
The damper is
a first cylindrical member fitted to the inner circumferential surface of the outer ring;
a second cylindrical member fitted to the outer peripheral surface of the inner ring;
an annular elastic buffer fixed to the inner circumferential surface of the first cylindrical member and the outer circumferential surface of the second cylindrical member;
In addition to providing
An outward flange portion is provided at the end of the cylindrical portion of the first cylindrical member to face the end surface of the outer ring, and between the end surface of the outer ring and the outward flange portion, It is characterized in that the elastic body is sandwiched in a compressed state.

According to the present invention, since the elastic buffer is provided, abnormal noise can be reduced by reducing vibrations caused by rotational fluctuations between the outer ring and the inner ring. In addition, by sandwiching the elastic body in a compressed state between the end face of the outer ring and the outward flange provided at the end of the first cylindrical member, high-frequency abnormal noise caused by tooth meshing can be suppressed. You can also get

The elastic buffer and the elastic body are preferably provided integrally.

As explained above, according to the present invention, noise can be suppressed.

FIG. 1 is a front view of a gear according to an embodiment of the present invention. FIG. 2 is a front view of the gear according to the embodiment of the present invention, with the damper removed. FIG. 3 is a schematic cross-sectional view of a gear according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Below, with reference to drawings, the form for implementing this invention is illustratively described in detail based on an Example. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in this example are not intended to limit the scope of this invention to only those, unless otherwise specified. .

(Example)
A gear according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a front view of a gear according to an embodiment of the present invention. FIG. 2 is a front view of the gear according to the embodiment of the present invention, with the damper removed. FIG. 3 is a schematic cross-sectional view of a gear according to an embodiment of the present invention. Note that FIG. 3 is a sectional view taken along line AA in FIG. Further, the outer ring and inner ring in FIG. 3 correspond to the AA sectional view in FIG. 2. Hereinafter, the center axis of the gear will be referred to as the "center axis."

<Gear configuration>
The gear 10 according to this embodiment is a so-called helical gear. This gear 10 includes an outer ring 100 having a plurality of teeth 110 on the outer periphery, an inner ring 200 arranged concentrically inside the outer ring 100, and an annular damper 300 arranged between the outer ring 100 and the inner ring 200. We are prepared. The tooth traces of the plurality of teeth 110 are configured to extend diagonally with respect to the central axis. The outer ring 100 and the inner ring 200 are made of a hard material. As this material, metal such as iron can be preferably used, but other hard materials such as resin materials can also be used.

A rotation preventing structure is provided between the inner circumferential surface of the outer ring 100 and the outer circumferential surface of the inner ring 200 to limit relative rotation between the outer ring 100 and the inner ring 200 within a certain range. More specifically, the inner circumferential surface of the outer ring 100 is provided with a plurality of protrusions 120 at intervals in the circumferential direction, and the outer circumferential surface of the inner ring 200 is also provided with a plurality of protrusions 220 at intervals in the circumferential direction. It is being In this embodiment, the plurality of protrusions 120 all have the same size and shape, and are provided at equal intervals in the circumferential direction. Similarly, all of the plurality of protrusions 220 have the same dimensions and shape, and are provided at equal intervals in the circumferential direction. A projection 220 is arranged between adjacent projections 120, and a gap is formed between the projections 120. With the above configuration, the outer ring 100 and the inner ring 200 are allowed to rotate relative to each other within a certain range, and when a rotational movement is applied by an external force and the protrusion 120 and the protrusion 220 come into contact, the outer ring 100 and the inner ring 200 are both rotated. Rotate.

A large diameter portion 130 to which the damper 300 is fixed is provided on the inner peripheral surface of the outer ring 100. Furthermore, a small diameter portion 230 to which the damper 300 is fixed is provided on the outer peripheral surface of the inner ring 200. As a result, the outer circumferential surface of the damper 300 is fitted to the inner circumferential surface of the large diameter portion 130 and the inner circumferential surface is fitted to the outer circumferential surface of the small diameter portion 230, so that the outer ring 100 and the inner ring 200 are connected to each other. It is fixed in the annular gap between.

Furthermore, the gear 10 according to the present embodiment has an inclination suppression structure that suppresses inclination of the outer ring 100 with respect to the inner ring 200 (inclination with respect to the central axis) while allowing relative rotation between the outer ring 100 and the inner ring 200 within a certain range. has. More specifically, a wall surface 150 provided on the outer ring 100 and perpendicular to the center axis line and a wall surface 250 provided on the inner ring 200 and perpendicular to the center axis line are provided to slide, thereby suppressing inclination. It has a structure. In this embodiment, the inner surface of the inward flange provided at the end of the outer ring 100 opposite to the side to which the damper 300 is fixed serves as the wall surface 150. Further, an end surface of the inner ring 200 at the end opposite to the side to which the damper 300 is fixed serves as the wall surface 250 described above.

By having such an inclination suppressing structure, the inclination of the outer ring 100 with respect to the inner ring 200 (inclination with respect to the central axis) is suppressed. That is, in the helical gear, when an external force (a rotational force) acts on the plurality of teeth 110 in the outer ring 100, a force that twists the outer ring 100 acts on the outer ring 100. Although this acts so that the outer ring 100 is inclined with respect to the inner ring 200, the inclination of the outer ring 100 can be suppressed by having the inclination suppressing structure. This suppresses the generation of abnormal noise.

<Damper>
The damper 300 will be explained in more detail. The damper 300 includes a first cylindrical member 310 fitted to the inner peripheral surface (large diameter portion 130) of the outer ring 100, and a second cylindrical member 310 fitted to the outer peripheral surface (small diameter portion 230) of the inner ring 200. member 320. The first cylindrical member 310 includes a cylindrical portion 311 and an outward flange portion 312 provided at an end of the cylindrical portion 311 . This outward flange portion 312 is provided so as to face the end surface of the outer ring 100.

The damper 300 also includes an annular elastic buffer 330 fixed to the inner peripheral surface of the first cylindrical member 310 and the outer peripheral surface of the second cylindrical member 320. The elastic buffer 330 is made of an elastomer material (such as rubber), and is directly fixed to the inner peripheral surface of the first cylindrical member 310 and the outer peripheral surface of the second cylindrical member 320 by vulcanization adhesive or the like. There is. The elastic shock absorber 330 includes a shock absorber main body 331 disposed so as to fill an annular gap between the inner peripheral surface of the first cylindrical member 310 and the outer peripheral surface of the second cylindrical member 320, and an outer ring. 100 and the outward flange portion 312, the elastic body 332 is sandwiched in a compressed state. The buffer main body 331 and the elastic body 332 are integrally provided. That is, by providing the elastomer material to cover the outward flange portion 312, the buffer main body 331 and the elastic body 332 are provided integrally. Note that the elastic body 332 is desirably provided so as to be in contact with the teeth 110 of the outer ring 100, and is desirably provided so that it can also be in contact with the mating teeth 500 that mesh with the teeth 110. Note that FIG. 3 also shows an enlarged cross-sectional view of the circled area in the figure, and in this enlarged view, the position of the tooth 500 when the tooth 110 meshes with the mating tooth 500 is indicated by a thick dotted line. It is shown in Further, the thickness of the elastic body 332 (thickness in the horizontal direction in the figure) is preferably set in a range of 0.5 mm or more and 3 mm or less.

<Excellent points of the gear (helical gear) according to this example>
According to the gear 10 according to this embodiment, rotational motion can be transmitted between the member (such as a rotating shaft) to which the inner ring 200 is fixed and the member (such as a gear) that meshes with the teeth 110 of the outer ring 100. . In the case of low torque, rotational motion is transmitted between the outer ring 100 and the inner ring 200 via the damper 300. Further, by providing the rotation prevention structure, rotational motion is directly transmitted between the outer ring 100 and the inner ring 200 when a torque of a certain level or more is applied. Since the damper 300 is provided, abnormal noise can be reduced by reducing vibrations caused by rotational fluctuations. Furthermore, since the elastic body 332 is sandwiched in a compressed state between the end surface of the outer ring 100 and the outward flange portion 312 provided at the end of the first cylindrical member 310, high-frequency differences due to meshing of the teeth are generated. A sound suppression effect can also be obtained. That is, by suppressing the vibration of the teeth that occurs when the teeth mesh with each other, the effect of suppressing high-frequency abnormal noise is exhibited.

10 gears 100 outer wheels 110 teeth 110 protrusions 130 large -diameter part 150 Walls 外 内 内 起 起 起 起 起 起 起 起 衝 衝 衝 衝 衝 衝 衝 衝 衝 衝 衝 衝 衝 衝 衝Body 331 Buffer body 332 Elastic body 500 Teeth

Claims (2)

an outer ring having multiple teeth on the outer periphery;
an inner ring disposed concentrically inside the outer ring;
an annular damper disposed between the outer ring and the inner ring;
Equipped with
The gear is provided with a rotation preventing structure that limits relative rotation between the outer ring and the inner ring within a certain range between the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring,
The damper is
a first cylindrical member fitted to the inner circumferential surface of the outer ring;
a second cylindrical member fitted to the outer peripheral surface of the inner ring;
an annular elastic buffer fixed to the inner circumferential surface of the first cylindrical member and the outer circumferential surface of the second cylindrical member;
In addition to providing
An outward flange portion is provided at the end of the cylindrical portion of the first cylindrical member to face the end surface of the outer ring, and between the end surface of the outer ring and the outward flange portion, A gear characterized by an elastic body being sandwiched in a compressed state. The gear according to claim 1, wherein the elastic buffer and the elastic body are integrally provided.

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