JPH0842635A - Torsional damper - Google Patents

Abstract

PURPOSE:To perform high-precise and easy formation of a pulley groove, to effect reduction of a manufacturing cost, and to provide strength and weight sufficient to a pulley. CONSTITUTION:A hub 1 is integrally rotatably coupled to a rotary shaft 5, such as a crank shaft, and a retainer 2 is mounted on the outer periphery of the hub 1. A pulley 4 is mounted on the outer periphery of the retainer 2 through a rubber 3. The pulley 4 consists of a pulley body 7 formed by effecting plastic processing of a steel sheet and a core 9 formed by mixing a number of metallic grains 8 in a synthetic resin material. The core 9 is formed approximately in an annular shape in a mold by a means, such as injection molding. A pulley body in the outer periphery of which a pulley groove 10 is formed is formed by effecting plastic processing of a steel sheet. The metallic grain 8 is a spherical body formed of a metallic material, such as a steel material, and the outside diameter thereof 0.2-1mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torsion damper mounted on various rotary shafts such as a crankshaft of an engine for damping torsional vibration generated on the rotary shafts.

[0002]

2. Description of the Related Art Generally, the crankshaft of an engine converts the reciprocating motion of a piston obtained in an explosion process into a rotary motion. appear. This torsional vibration not only causes noise in the engine and wear of the bearing, but also is transmitted to the output side device and causes damage to the device. In some cases, the crankshaft is damaged. It can be a cause. For this reason, a torsional damper for damping torsional vibrations is attached to the output side end of the crankshaft, and the rotational force of the crankshaft is transmitted to the output side device via this torsional damper. Has become.

In the torsional damper, a pulley is mounted on an outer periphery of a hub connected to a crankshaft via an elastic body, and the elastic force of the elastic body allows the pulley to be slightly displaced relative to the hub in a rotational direction. Has become.

In order to rotate the pulley of the torsional damper stably without being affected by vibration or the like, it is necessary to increase the weight of the pulley to some extent so that a sufficient inertial force works during the rotation. There is. For this reason,
Conventionally, the pulley is formed of a metal material such as cast iron or steel. In this case, a pulley groove is formed on the outer circumference of the pulley by cutting with a machine tool.

[0005]

However, when machining the pulley groove, high finishing accuracy is required. Therefore, it takes a lot of time and labor to cut the pulley groove, resulting in an increase in manufacturing cost.

The present invention has been made in order to solve the above problems, and an object thereof is to easily form a pulley groove with high precision, to reduce the manufacturing cost, and moreover as a pulley. It is to provide a torsional damper that can obtain various strength and weight.

[0007]

In order to achieve the above object, the invention of claim 1 is a torsional damper in which a pulley is mounted on the outer periphery of a hub connected to a rotary shaft via an elastic body. The pulley is composed of a member obtained by mixing a large number of metal particles with a synthetic resin material.

According to a second aspect of the present invention, in a torsional damper in which a pulley is mounted on the outer periphery of a hub connected to a rotary shaft via an elastic body, the pulley is an outer member formed by plastically working a metal plate. And an inner member formed by mixing a large number of metal particles in a synthetic resin material.

In the invention of claim 3, the outer member is provided so as to surround the entire surface of the inner member. Claim 4
In the invention, the metal particles are spherical bodies having an outer diameter of 0.2 to 1 mm.

[0010]

Therefore, according to the first aspect of the present invention, since the pulley is made of a member in which a large number of metal particles are mixed with a synthetic resin material, the pulley groove is made high by injection molding without the need for cutting. It can be easily formed with high precision, and the pulley can have a sufficient weight.

According to the second aspect of the invention, since the outer member of the pulley is formed by plastically working the metal plate, the pulley groove can be easily formed with high precision without the need for cutting. Further, an inner member formed by mixing a large number of metal particles with a synthetic resin material is arranged inside the outer member. Therefore, even if the outer member is a relatively low-rigidity and light-weight member formed by plastic working of a metal plate, sufficient strength can be obtained for the pulley as a whole and sufficient weight can be obtained.

According to the third aspect of the invention, the outer member and the inner member are firmly integrated. According to the invention of claim 4, since the metal particles are very small spheres, when the pulley or the inner member is formed by injection molding or the like, the metal particles are evenly distributed in a specific place without being biased. As a result, the weight balance of the pulleys is kept good.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. As shown in FIG. 1, the hub 1 is made of a metal material such as steel and is integrally rotatably coupled to a rotary shaft 5 such as a crankshaft. The ring-shaped retainer 2 is also made of a metal material such as steel and is attached to the outer periphery of the hub 1 by means of press fitting or the like. The pulley 4 having a substantially ring shape is attached to the outer periphery of the retainer 2 via the rubber 3 as an elastic body.

The hub 1 having the retainer 2 mounted thereon and the pulley 4 are positioned and fixed to each other to form a ring-shaped gap between the members 2 and 4, and a vulcanized ring-shaped rubber 3 is formed in the gap. By pressing in, the torsional damper 6
Is completed. In addition, by setting the hub 1 with the retainer 2 and the pulley 4 set in a mold (not shown), both members 1, 4
In the state where they are positioned and fixed to each other, the unvulcanized rubber 3 is injected into the ring-shaped gap between the retainer 2 and the pulley 4. Then, the retainer 2 and the pulley 4 are inserted through the rubber 3.
The torsional damper 6 may be completed by vulcanizing and adhering.

The pulley 4 is composed of a pulley body 7 as an outer member made by plastically working a steel plate, and a core 9 as an inner member made by mixing a large number of metal particles 8 in a synthetic resin material. . The metal particles 8 are spheres made of a metal material such as steel and have an outer diameter of 0.2 to 1 mm, preferably 0.2 to 0.5 mm.

The core 9 is formed into a substantially ring shape by means such as injection molding in a mold (not shown). Then, so as to surround the entire surface of the formed core 9,
By plastically working a steel plate, a pulley body 7 having a pair of V-belt pulley grooves 10 on the outer peripheral surface is formed. Further, in the pulley main body 7, both axial end portions of the steel plates forming the main body 7 are bent toward the inner peripheral side and joined at both end edges. In this way, by surrounding the entire surface of the core 9 with the pulley body 7, the both 7 and 9 are firmly integrated.

The pulley body 7 is made of a metal plate other than a steel plate,
For example, a light alloy plate such as an aluminum alloy may be used. Now, in this embodiment, since the pulley body 7 is formed by plastically working a metal plate, the pulley groove 10
Can be easily formed with high precision without the need for cutting, and the manufacturing cost can be reduced. Further, inside the pulley body 7, a core 9 formed by mixing a large number of metal particles 8 with a synthetic resin material is arranged. Therefore, even if the pulley body 7 is a relatively low-rigidity and light-weight one formed by plastic working of a metal plate, it is possible to obtain sufficient strength as the entire pulley 4. Moreover, the weight of the pulley 4 can be made sufficiently heavy due to the large number of metal particles 8 contained in the core 9, and a sufficient inertial force acts on the pulley 4 during its rotation. As a result, the pulley 4 can be stably rotated without being affected by vibration or the like. Further, by forming the outer peripheral side of the pulley 4 with a metal plate, it is possible to make the pulley 4 excellent in abrasion resistance.

Further, in this embodiment, the metal particles 8 are 0.2-1.
Since it is a very small sphere having an outer diameter of mm, when the core 9 is formed by injection molding or the like, the metal particles 8 are evenly distributed in a specific place without being biased. As a result, the pulley 4
The weight balance can be kept good, and the pulley 4 can be stably rotated with good balance.

Further, by changing the amount of the metal particles 8 contained in the core 9, even the pulleys 4 having the same size can have different weights. Therefore, the weight of the pulley 4 can be easily changed and adjusted to an optimum weight according to the purpose of use.

The present invention is not limited to the above-described embodiment, and the configurations of the respective parts may be modified and embodied as follows, for example, without departing from the spirit of the present invention.

(1) As shown in FIG. 2, the pulley body 7
In place of the V-belt pulley groove 10 of the above embodiment,
Forming a pair of pulley grooves 12 for a flat belt by plastic working. In this case, it goes without saying that the core 9 is formed in a shape corresponding to the shape of the pulley body 7. Further, as shown in the figure, the retainer 2 may not be provided.
Further, a convex portion 1a extending in the circumferential direction is formed on the outer peripheral surface of the hub 1, and a concave groove 4a corresponding to the convex portion 1a is formed on the inner peripheral surface of the pulley 4. With this configuration, the hub 1, the rubber 3, and the pulley 4 are reliably prevented from being displaced in the axial direction.

(2) The pulley 4 is constructed by forming a hollow pulley main body 7 by plastic working of a steel plate and then injecting and filling a core 9 before hardening into the internal space of the pulley main body 7. In this case, a through hole for filling may be formed on the side surface of the pulley body 7 or the like.

(3) The pulley body 7 should be provided only on the outer peripheral side of the core 9. (4) As shown in FIG. 3, the pulley 4 is composed of only the core 9 in the above-described embodiment, that is, a member formed by mixing a large number of metal particles 8 in a synthetic resin material. In this case, the pulley groove 10 can be easily formed with high precision by injection molding or the like without the need for cutting, and the pulley 4 can have a sufficient weight.

[0024]

As described in detail above, the present invention has the following excellent effects. According to the first and second aspects of the present invention, the pulley groove can be easily formed with high precision, the manufacturing cost can be reduced, and the pulley can have sufficient strength and weight. Also, the weight of the pulley can be easily changed and adjusted.

According to the invention of claim 3, the outer member and the inner member can be firmly integrated. According to the invention of claim 4, the weight balance of the pulley can be kept good and the rotation thereof can be stabilized.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a torsional damper embodying the present invention.

FIG. 2 is a partially cutaway perspective view showing another example of the present invention.

FIG. 3 is a partially cutaway perspective view showing another example of the present invention.

[Explanation of Codes] 1 ... Hub, 3 ... Rubber as elastic body, 4 ... Pulley, 5 ...
Rotating shaft, 6 ... Torsional damper, 7 ... Pulley body as outer member, 8 ... Metal particles, 9 ... Core as inner member, 10 ... Pulley groove, 12 ... Pulley groove.

Claims (4)

[Claims] 1. A torsion damper in which a pulley is mounted on the outer circumference of a hub connected to a rotating shaft via an elastic body, wherein the pulley is made of a member formed by mixing a large number of metal particles into a synthetic resin material. The configured torsional damper. 2. A torsional damper in which a pulley is mounted on the outer circumference of a hub coupled to a rotating shaft via an elastic body, wherein the pulley is an outer member formed by plastically working a metal plate,
A torsional damper composed of an inner member formed by mixing a large number of metal particles into a synthetic resin material. 3. The torsion damper according to claim 2, wherein the outer member is provided so as to surround the entire surface of the inner member. 4. The metal particles have an outer diameter of 0.2 to 1 mm.
The torsional damper according to any one of claims 1 to 3, which is a spherical body.