JPH0712653U - Rotating bodies such as gears and pulleys - Google Patents

Abstract

(57) [Summary] [Purpose] To suppress vibration and sufficiently reduce noise while having a simple structure and lightweight, and to manufacture a rotating body simply and at low cost. An annular engagement groove 20 is formed in a plate surface 18a of the gear body 18, and a ring-shaped main body portion 22 engages with the annular engagement groove 20, and the gear main body 18 and the ring-shaped main body portion 22 are engaged. Are in surface contact with each other. The ring-shaped body portion 22 is
It is frictionally fastened to the gear body 18 by rivets 26. The number and size of the rivets 26 are adjusted to optimally set the frictional force generated between the gear body 18 and the ring-shaped body portion 22.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a gear such as an engine timing gear and the like, and a rotating body such as a pulley, particularly a rotating body having a vibration damping structure.

[0002]

[Prior art]

 Rotating bodies such as power transmission gears and pulleys used in various machines such as engines and pulleys receive torque fluctuations during rotation from the shaft that fixes the rotating bodies and the belt that is hung on the pulleys. As shown in FIG. 8, the rotating body 40 may vibrate in the plate thickness direction to generate noise.

Conventionally, in order to reduce such noise, a cover is provided for sound insulation, a sound absorbing material is used for sound absorption, or a vibration damping member such as a snap ring is attached to the rotating body. By pressing the snap ring toward the outer circumference of the rotating body, the frictional force between the rotating body and the snap ring absorbs the vibration of the rotating body to reduce noise.

[0004]

[Problems to be solved by the device]

 However, if a special sound insulating member, sound absorbing member, or noise reducing member is provided in addition to the main body of the rotating body as in these conventional techniques, the structure becomes complicated and the manufacturing is troublesome. The weight increases, and the cost also increases. In addition, it may be difficult to provide such vibration suppressing means in view of space.

The object of the present invention is to solve the above-mentioned problems, and to provide a vibration control structure to the rotating body itself so as to sufficiently suppress noise while having a simple structure and light weight, and also to provide a simple and low cost. The object is to provide a rotating body such as a gear or a pulley that can be manufactured by the manufacturer.

[0006]

Means for Solving the Problems As a means for solving the above problems, the present invention provides a rotating body such as a gear or a pulley, which comprises a rotating body such as a gear or a pulley. Provided is a rotating body such as a gear or a pulley in which a ring-shaped main body portion that engages in the formed annular engagement groove is frictionally fastened to a rotating body main body by a fastening means. In this specification, the rotating body means a gear body, a pulley body, or the like.

[0007]

[Action]

 In this way, by frictionally making surface contact between the rotor body and the ring-shaped body portion, a frictional force is generated between these members, and vibration of the rotor body is sufficiently suppressed to reduce vibration. be able to. Further, since the ring-shaped main body portion engages with the annular engagement groove of the rotary body main body to complement the rotary body main body, the rotary body can be easily and easily manufactured without increasing the weight and space or increasing the cost. The rotating body can be manufactured at low cost.

[0008]

【Example】

 1 and 2 show a gear 10 to which the present invention is applied, which includes a boss 12, a rim 14 and these bosses 12. A gear body 18 including a web 16 connecting the rim 14 and the rim 14. 1 and 2, reference numeral 14a indicates a tooth of the gear body 18.

As shown in FIGS. 2 (A) and 2 (B), the gear main body 18 has an annular engagement groove 20 on its plate surface 18 a that is in surface contact with a ring-shaped main body portion 22. . As shown in FIGS. 2A and 2B, the ring-shaped body portion 22 engages with the annular engagement groove 20 and complements the gear body 18. In this case, as shown in FIG. 2 (A), the annular engagement groove 20 is formed in conformity with the shape of the ring-shaped main body portion 22 so that the gear main body 18 and the ring-shaped main body portion 22 are in surface contact with each other. The width is such that a slight clearance is generated between the gear body 18 and the ring-shaped body portion 22 so that relative displacement occurs between the gear body 18 and the ring-shaped body portion 22.

As shown in FIG. 3, the ring-shaped body portion 22 is formed by cutting off a part of the gear body 18, and its cross section is shown in FIG. 2 (A) in the illustrated embodiment. As shown, in order to obtain a large contact area with the bottom surface of the annular engaging groove 20, the shape is a quadrangle, but of course, any other cross section can be used. As described above, the ring-shaped main body portion 18 is formed by cutting out a part of the gear main body 18, and therefore, even when the ring main body portion 18 is engaged with the gear main body 18, there is a damping member on the outer shape. It is no different from the gear that is not used, and therefore, it can be used to suppress vibration sufficiently even in a small space where it is difficult to provide vibration suppressing means. As shown in FIG. 3, the ring-shaped main body portion 22 is provided with an appropriate number of fastening means through holes 23.

As shown in FIGS. 2A and 2B, the ring-shaped main body portion 22 is frictionally fastened to the gear main body 18 by the fastening means 24. Therefore, a frictional force (see arrow F in FIG. 4) due to the mutual displacement is generated between the gear body 18 and the ring-shaped body portion 22 that are in surface contact with each other, and this frictional force (see arrow F in FIG. 4). As a result, the force in the vibration direction of the gear 10 (see arrow F ′ in FIG. 4) is suppressed, and noise can be sufficiently reduced. In particular, since vibration is sufficiently suppressed without providing a special noise reduction member, it is possible to sufficiently reduce noise while having a simple and lightweight structure, and as a result, to manufacture easily and at low cost. be able to.

As the tightening means 24, the rivet 26 shown in FIG. 4 or other bolts can be used. In this case, depending on the magnitude of the frictional force (see arrow F in FIG. 4) generated between the gear body 18 and the ring-shaped body portion 22, as shown in FIG. Since they are different, it is necessary to appropriately adjust the number and size of these rivets 26 and the like.

That is, as shown in FIG. 5, if the frictional force F (see FIG. 5) is too small (see point A in FIG. 5), the vibration cannot be suppressed sufficiently, and conversely, the frictional force F If (see FIG. 5) is too large (see point B in FIG. 5), relative displacement is less likely to occur between the gear body 18 and the ring-shaped body portion 22, and the gear body 18 and the ring-shaped body portion 22 are integrally displaced. Inability to exert effect. Therefore, in order to effectively suppress the vibration, it is necessary to set the frictional force F generated between the gear body 18 and the ring-shaped body portion 22 to an optimum value (see point C in FIG. 5).

In this case, the frictional force F (see FIG. 5) is expressed by the following formula: frictional force (F) = friction coefficient (μ) of mating surface × normal force (N) applied to mating surface. By properly setting the number and thickness of the attachment means 24, the vertical drag force (N) applied to this mating surface is adjusted to generate the optimum friction force (F). That is, in order to increase the normal force (N) applied to the mating surface, the number of rivets 26 and the like is increased and the thickness is increased, while in the case of decreasing the normal force (N) applied to the mating surface, rivets are used. The number of 26 or the like is reduced and the thickness is reduced. By thus obtaining the optimum rubbing force F (see point B in FIG. 5), vibration can be effectively suppressed and noise can be sufficiently reduced.

An example in which the present invention is applied to the pulley 30 is shown in FIGS. 6 and 7. The pulley 30 is composed of a boss 32 and a pulley main body 36 having a rim 34 integrally provided on the boss 32 and having a rim 34 having a pulley groove 34a on which a belt (not shown) is hooked.

Also in this pulley 30, the pulley body 36 has an annular engagement groove 20 on its plate surface 36 a that is in surface contact with the ring-shaped main body portion 22. As shown in FIGS. 6 and 7, the ring-shaped main body portion 22 engages with the annular engagement groove 20 to complement the pulley main body 36.

Also in this embodiment, the ring-shaped body portion 22 is frictionally fastened to the pulley body 36 by the fastening means 24 such as the rivet 26 as shown in FIGS. 6 and 7. The frictional force (see arrow F in FIG. 7) caused by the relative displacement of the pulley 30 suppresses the force in the vibration direction of the pulley 30 (see arrow F ′ in FIG. 7) to reduce noise. Therefore, similarly to the embodiment applied to the gear body 18, it is necessary to appropriately adjust the thickness and the number of the rivets 26, which are the tightening means 24, to generate the optimum frictional force for suppressing the vibration. .

[0018]

[Effect of device]

 According to the present invention, as described above, while the structure is simple and lightweight, the frictional force generated between the gear main body or the pulley main body and the ring-shaped main body portion sufficiently suppresses the vibration of the main body of the rotating body to reduce the vibration. It can be reduced. In addition, the ring-shaped body part complements the body of the rotating body by engaging in the annular engaging groove of the body of the rotating body, so that it can be rotated easily and at low cost without increasing the weight or space or increasing the cost. There is a real benefit of being able to manufacture the body.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a gear to which the present invention is applied.

2A is an enlarged cross-sectional view of a main part of a gear to which the present invention is applied, and FIG. 2B is a partial front view of a gear to which the present invention is applied.

FIG. 3 is a front view of a ring-shaped body portion used in the present invention.

FIG. 4 is a sectional view showing a damping state of a gear to which the present invention is applied.

FIG. 5 is a diagram showing the relationship between the frictional force and the vibration damping effect obtained by the tightening means used in the present invention.

FIG. 6 (A) is an enlarged sectional view of an essential part of a pulley to which the present invention is applied, and FIG. 6 (B) is a partial front view of a pulley to which the present invention is applied.

FIG. 7 is a sectional view showing a vibration damping state of a pulley to which the present invention is applied.

FIG. 8 is a side view showing a vibration state of a general rotating body.

[Explanation of symbols]

 10 gear 12 boss 14 rim 16 web 18 gear body 18a plate surface of gear body 20 annular engaging groove 22 ring-shaped body portion 23 tightening means through hole 24 tightening means 26 rivet 30 pulley 32 boss 34 rim 34a pulley groove 36 pulley body

Claims (1)

[Scope of utility model registration request] 1. In a rotating body such as a gear or a pulley, which comprises a rotating body such as a gear or a pulley, a ring-shaped body portion that engages in an annular engagement groove formed on a plate surface of the rotating body is tightened. A rotating body such as a gear or a pulley, which is frictionally fastened to the rotating body by means.