JP2006071096A - Centrifugal clutch and its assembly method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifugal clutch capable of suppressing vibration of a clutch housing and suppressing occurrence of abnormal sound sufficiently. <P>SOLUTION: This centrifugal clutch is composed of the clutch housing 12 composed of a circular cylindrical part 12a whose inner face becomes a slide-contact face and a bottom plate part 12b covering one end part of the circular cylindrical part, a rotary shaft which has the same axis as the circular cylindrical part of the clutch housing and to which rotation force is transmitted by the clutch housing, a centrifugal shoe for connecting with the clutch housing or disconnecting from it by rotating around the rotary shaft and coming into contact with or leaving the slide-contact face, and a vibration control cover 17 put on an outer side of the circular cylindrical part. The clutch housing and the vibration control cover have contact parts 30, 40 coming into contact mutually, a non-contact part 50 not in contact, and positioning marks 14, 22 for positioning the clutch housing and the vibration control cover at predetermined relative positions for preventing occurrence of abnormal sound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a centrifugal clutch and an assembling method thereof.

  A centrifugal clutch provided in a motorcycle or the like includes a substantially saddle-shaped clutch housing having a cylindrical portion whose inner surface is a sliding contact surface, and a bottom plate portion covering one end portion of the cylindrical portion, and is coaxial with the cylindrical portion of the clutch housing. A rotating shaft to which rotational force is transmitted by the clutch housing, and a centrifugal shoe that rotates around the rotating shaft and contacts / disengages from the sliding contact surface to connect / disconnect to the clutch housing. .

  Such centrifugal clutches often generate unpleasant noises when the clutch is engaged. One of the causes is based on the vibration of the cylindrical portion of the clutch housing.

FIG. 6 is an explanatory view schematically showing how the clutch housing vibrates.
A circle c represents a cylindrical portion of the clutch housing, and a centrifugal shoe (not shown) is pressed against the inner surface while rotating. In the example of (A), vibration occurs at a period of 120 degrees along the circumference, and vibration nodes d and antinodes e appear repeatedly every 60 degrees. The node d does not vibrate, and the antinode e vibrates in the radial direction as indicated by an arrow. Similarly, in the example of (B), vibration occurs at a period of 90 degrees along the circumference, and vibration nodes d and antinodes e appear repeatedly every 45 degrees. The circumferential period of such vibration varies depending on the rotational speed, material, weight, and shape of the clutch housing of the centrifugal shoe.

  When the antinode e of the vibration is displaced inward in the radial direction due to such vibration of the clutch housing, the centrifugal shoe contacts while rotating. Abnormal noise is generated by intermittent contact between the vibrating clutch housing and the centrifugal shoe. Therefore, it is considered that generation of abnormal noise is suppressed by suppressing such vibration of the clutch housing, and particularly suppressing the displacement of the antinode portion e.

  On the other hand, a housing damping structure in which a clutch housing is covered with a damping plate has been proposed to suppress the generation of abnormal noise in the centrifugal friction engagement device (Patent Document 1). The housing damping structure described in Patent Document 1 gently releases the press-fitting allowance of the tip portion of the damping plate that is press-fitted into the clutch housing, and forms a notch along the axial direction at the tip portion. Is going to disappear.

  However, the housing damping structure described in Patent Document 1 cannot sufficiently suppress the radial displacement of the antinode portion of the vibration of the clutch housing shown in FIG. 6, and an effective noise suppressing effect is obtained. Absent.

Japanese Patent No. 3322015

  The present invention has been made in consideration of the above prior art, and one object of the present invention is to provide a centrifugal clutch that can effectively suppress vibration of the clutch housing and sufficiently suppress the generation of abnormal noise. . Another object is to provide a method for assembling such a centrifugal clutch. Another object is to provide a vehicle such as a motorcycle having such a centrifugal clutch.

  In order to achieve the above object, one centrifugal clutch provided by the present invention includes a clutch housing having a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end of the cylindrical portion, A rotating shaft that is coaxial with the cylindrical portion and receives rotational force from the clutch housing, and a centrifugal shoe that rotates around the rotating shaft and contacts or separates from the sliding contact surface to connect or disconnect the clutch housing And a centrifugal clutch comprising an anti-vibration cover placed on the outside of the cylindrical portion. The clutch housing and the vibration-proof cover have contact portions that contact each other and non-contact portions that do not contact each other, and a positioning mark that positions the clutch housing and the vibration-proof cover at a predetermined relative position that prevents the occurrence of abnormal noise. It is characterized by having.

  In the centrifugal clutch having such a configuration, the clutch housing and the vibration isolating cover are disposed in a state in which the relative positional relationship that can suppress the generation of the abnormal noise is properly maintained due to the presence of the positioning mark. In other words, the two are correctly brought into contact with each other in a portion (that is, the contact portion) effective in suppressing the generation of abnormal noise while forming a non-contact portion. Thereby, a high anti-vibration effect (anti-noise occurrence prevention effect) can be realized.

Further, according to the technique disclosed herein, by providing a positioning mark, the clutch housing and the vibration isolating cover are always positioned at a relative position suitable for preventing the occurrence of abnormal noise by extending the vibration. Can be assembled.
Accordingly, the present invention provides a centrifugal clutch assembling method as another aspect.
The centrifugal clutch assembling method disclosed herein includes a clutch housing including a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end portion of the cylindrical portion, and is coaxial with the cylindrical portion of the clutch housing by a clutch housing. A rotating shaft to which a rotational force is transmitted, a centrifugal shoe that rotates around the rotating shaft and contacts or separates from the sliding contact surface to connect or disconnect the clutch housing; and an outer side of the cylindrical portion This is an assembling method of a centrifugal clutch comprising a vibration-proof cover covered.
Then, as the clutch housing and the vibration-proof cover, a clutch housing and a vibration-proof cover having positioning marks for positioning the clutch housing and the vibration-proof cover at a predetermined relative position for preventing the occurrence of abnormal noise are prepared, The anti-vibration cover is covered on the outer side of the clutch housing cylindrical portion so that a contact portion that contacts each other while being positioned at a predetermined relative position and a non-contact portion that does not contact each other are provided.
According to this method, it is possible to stably assemble a centrifugal clutch that exhibits a high anti-vibration effect (an effect of preventing abnormal noise generation).

In a preferred aspect of the centrifugal clutch disclosed herein, a hollow hole is formed in the bottom plate portion of the clutch housing. Further, the lightening hole and the contact portion of the vibration-proof cover are positioned so as to be in a predetermined position.
A lightening hole (ie, a through hole) may be a suitable positioning mark. In addition, the formation of such a hollow hole contributes to the weight reduction of the centrifugal clutch.
Therefore, the centrifugal clutch assembling method using the clutch housing in which such a hollow hole is formed is a preferred embodiment of the centrifugal clutch assembling method disclosed herein.

In a preferred aspect of the centrifugal clutch disclosed herein, a convex portion that is in pressure contact with the outer surface of the cylindrical portion is formed on the inner surface of the vibration-proof cover, and the convex portion and the contact portion of the clutch housing are connected to each other. It is characterized by being positioned so as to be in a predetermined position.
The convex part press-contacted to the cylindrical outer surface of the clutch housing can constitute a contact part that exhibits a high anti-vibration effect (anti-noise generation preventing effect).
Accordingly, the centrifugal clutch assembling method using the vibration-proof cover having such a convex portion is a preferred embodiment of the centrifugal clutch assembling method disclosed herein.

In a further preferred aspect of the centrifugal clutch disclosed herein, a bottom hole is formed in the bottom plate portion of the clutch housing, and a convex portion that presses against the outer surface of the cylindrical portion is formed on the inner surface of the vibration-proof cover. Is formed. And the said hollowing hole and the said convex part are positioned so that it may become a predetermined position, It is characterized by the above-mentioned.
The convex part of the inner surface of the vibration-proof cover that covers the clutch housing is pressed against the outer peripheral surface of the clutch housing, so that the displacement in the radial direction due to the vibration of the clutch housing can be reliably suppressed, and the generation of abnormal noise can be effectively prevented. it can.

In a particularly preferred aspect, the convex portion is arranged at substantially the same position as the lightening hole with respect to the circumferential position of the inner surface of the vibration-proof cover.
The position of the lightening hole formed in the bottom plate portion of the clutch housing is likely to become an antinode of vibration. By arranging the convex portion of the anti-vibration cover near this position and pressing the clutch housing cylindrical portion from the outside, the cylindrical portion The generation of abnormal noise can be suppressed by effectively suppressing the vibration.
Accordingly, the centrifugal clutch assembling method using the vibration-proof cover having such a convex portion is a preferred embodiment of the centrifugal clutch assembling method disclosed herein.

In another preferable aspect of the centrifugal clutch disclosed herein, at least two of the convex portions are formed on the cylindrical side edge of the vibration-proof cover, and two adjacent vibration-proof covers are adjacent to each other. The side edge part between convex parts is the shape shifted | deviated inside from the virtual circle which connects the protrusion of the said convex part centering | focusing on the said rotating shaft.
When the anti-vibration cover having such a shape is placed on the outer side of the clutch housing cylindrical portion, the convex portion (protrusion end) contacts the clutch housing cylindrical portion to suppress vibration, and further from the virtual circle between two adjacent convex portions. The side edge of the shape shifted inward, that is, the side edge having a gentler curvature than the imaginary circle (hereinafter also referred to as “gradually curved side edge”) can contact the clutch housing. As a result, it contacts the outer surface of the clutch housing in a wider range (in other words, more contact portions). As a result, vibration absorption energy is increased, and the effect of suppressing abnormal noise can be improved.

In another preferable aspect of the centrifugal clutch disclosed herein, the contact portion of the clutch housing and the contact portion of the vibration-proof cover are in surface contact with the line contact portion that makes line contact with each other. And a surface contact portion. Preferably, one of the contact portion of the clutch housing and the contact portion of the vibration-proof cover includes a convex portion that makes a line contact with the other contact portion facing each other.
By providing the line contact portion and the surface contact portion in this manner, the outer surface of the clutch housing and the vibration-proof cover come into contact with each other in a wider range (in other words, more contact portions). Thereby, vibration absorption energy becomes large and the noise suppression effect can be improved.

  In another preferable aspect of the centrifugal clutch disclosed herein, a clutch housing including a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end of the cylindrical portion, and the cylindrical portion of the clutch housing A rotary shaft that is coaxial with the clutch housing, and a rotational force is transmitted by the clutch housing, and a centrifugal shoe that rotates around the rotary shaft and contacts or separates from the sliding contact surface to connect or disconnect the clutch housing; A centrifugal clutch comprising an anti-vibration cover placed on the outside of the cylindrical part, wherein the anti-vibration cover is in contact with the clutch housing at a position other than a vibration node of the clutch housing cylindrical part. And a non-contact portion that does not contact the clutch housing on both sides in the circumferential direction of the contact portion.

In the centrifugal clutch having such a configuration, contact between the clutch housing and the anti-vibration cover at a vibration node in the cylindrical portion of the clutch housing that hardly contributes to vibration prevention is avoided, and the above-described position at a position beneficial for vibration prevention is avoided. Generation of abnormal noise can be effectively prevented by contact between the two.
In particular, a centrifugal clutch having a positioning mark that can easily avoid contact between the clutch housing and the vibration-proof cover at a vibration node and can position the clutch housing and the vibration-proof cover at a predetermined position is particularly preferable.

According to another aspect of the present invention, a clutch housing including a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end portion of the cylindrical portion, and a rotational force is generated by the clutch housing coaxially with the cylindrical portion of the clutch housing. A rotating shaft to be transmitted, a centrifugal shoe that rotates around the rotating shaft and contacts or separates from the sliding contact surface to connect or disconnect the clutch housing; and a protection covering the outside of the cylindrical portion. A method of assembling a centrifugal clutch comprising a vibration cover, wherein the clutch housing cylindrical portion is brought into contact with at least two positions other than a predetermined vibration node of the clutch housing cylindrical portion, and a circle at the contact portion is formed. A non-contact portion that does not come into contact with the cylindrical portion of the clutch housing is provided on both sides in the circumferential direction. Providing a centrifugal clutch assembly wherein the covering the vibration isolating cover.
According to this method, it is possible to stably assemble a centrifugal clutch that exhibits a high anti-vibration effect (an effect of preventing abnormal noise generation).
In particular, a clutch housing and a vibration isolating cover having positioning marks that can easily avoid contact between the clutch housing and the vibration isolating cover at a vibration node and can position the clutch housing and the vibration isolating cover at a preferable predetermined position are used. It is preferable.

The present invention also provides a motorcycle or other vehicle including any one of the centrifugal clutches disclosed herein.
The vehicle according to the present invention includes the centrifugal clutch disclosed herein, and as a result, the generation of abnormal noise from the clutch is suppressed.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings, but the present invention is not intended to be limited to these specific examples.
FIG. 10 is a side view of a motorcycle (here, a scooter) that is a typical example of a vehicle including the centrifugal clutch according to the present embodiment.
As shown in this figure, a motorcycle 100 according to this embodiment is roughly divided into a front fork 101 pivotally supported by a vehicle body frame, a front wheel 102 mounted at the lower end of the front fork 101, and the front fork 101. A handle 103 provided at the upper end of the fork 101, a seat 104 disposed at the upper part of the body frame, an engine unit 106 provided below the seat 104, and the engine unit 106 are connected to the centrifugal unit according to the present embodiment. A belt-type continuously variable transmission 105 having a clutch and a rear wheel 107 to which power is transmitted from the continuously variable transmission 105 are provided.
The motorcycle 100 of the present embodiment may be the same as that mounted on a conventional motorcycle having the same shape with respect to mechanisms other than the centrifugal clutch described below, and a detailed description of the prior art will be omitted. Note that a motorcycle suitable as a vehicle for carrying out the present invention means a motorcycle, and includes a motorbike and a scooter. A vehicle that can turn by tilting the vehicle body can be included in the motorcycle here. Therefore, even if at least one of the front wheels and the rear wheels is two or more and the number of tires is counted as a tricycle / four-wheel vehicle (or more), it can be included in the “motorcycle”.
The present invention is not limited to the motorcycle shown in the embodiment, and the present invention is preferably applicable to other vehicles including a centrifugal clutch. For example, the centrifugal clutch of the present invention can be preferably applied to a so-called saddle-ride type vehicle including a four-wheel buggy (ATV: All Terrain Vehicle) and a snowmobile other than a motorcycle. The saddle-ride type vehicle can widely include a vehicle having a riding form similar to or similar to a motorcycle. Further, the centrifugal clutch of the present invention can be preferably applied to a game or racing vehicle such as an engine or a cart with a motor.

  FIG. 1 is a cross-sectional view showing a rough structure of a continuously variable transmission including a centrifugal clutch according to the present embodiment. The continuously variable transmission 1 includes a drive sheave 3 attached to the drive shaft 2 and a driven sheave 5 attached to the driven shaft 4. An endless belt 6 is stretched between the driving sheave 3 and the driven sheave 5. The drive sheave 3 includes a pair of movable sheave 7 and fixed sheave 8. The driven sheave 5 includes a pair of movable sheaves 9 and a fixed sheave 10. The movable sheaves 7 and 9 can slide along the drive shafts 2 and 4, respectively. On the other hand, the fixed sheaves 8 and 10 have their axial positions fixed. The position of the endless belt indicated by reference numeral 6 in FIG. 1 is the belt position at the maximum reduction ratio (LOW). The position of the endless belt indicated by reference numeral 6a indicates the belt position at the minimum reduction ratio (TOP).

As shown in FIG. 1, the main part of the centrifugal clutch 11 according to the present embodiment is mounted on a driven shaft 4 corresponding to the rotating shaft. Such a centrifugal clutch 11 includes a clutch housing 12 and a centrifugal shoe 13 mounted coaxially on the inside thereof. The clutch housing 12 includes a cylindrical portion 12a and a bottom plate portion 12b that covers one end surface of the cylindrical portion 12a, and typically has a substantially bowl shape.
The inner surface of the cylindrical portion 12a of the clutch housing 12 forms a sliding contact surface, and the centrifugal shoe 13 is pressed against the sliding contact surface. On the other hand, the bottom plate portion 12b of the clutch housing 12 is formed with a plurality of lightening holes 14 for weight reduction. Further, the lightening hole 14 constitutes a positioning mark according to the present embodiment.

Thus, the centrifugal clutch 11 having the above-described configuration operates as follows.
That is, the rotation of the drive sheave 3 is transmitted to the driven sheave 5 by the belt 6. The rotation of the driven sheave 5 is transmitted to the carrier 16 of the centrifugal shoe 13 through the hollow shaft 15, and the centrifugal shoe 13 rotates accordingly. The centrifugal shoe 13 spreads to the outside by the centrifugal force during the rotation, and eventually comes into pressure contact with the inner surface (sliding contact surface) of the cylindrical portion 12a of the clutch housing 12 to connect the clutch. Thereby, the clutch housing 12 rotates, the rotational force is transmitted, and the driven shaft (the above-mentioned rotating shaft) 4 rotates.
Note that an anti-vibration cover 17 according to the present embodiment is placed on the outside of the clutch housing 12 (see FIGS. 3A and 3B). That is, the cylindrical portion 12 a of the clutch housing 12 is disposed in a state where it is press-fitted into the vibration-proof cover 17.

FIG. 2 is a view for explaining the arrangement of the centrifugal shoe 13 according to this embodiment. 2B is a plan view, and FIG. 2A is a cross-sectional view taken along the line AA in FIG. 2B.
In this example, three centrifugal shoes 13 are mounted on a carrier 16 via springs 18. The spring 18 biases each centrifugal shoe 13 to the front side (counterclockwise side). The centrifugal shoe may have the same configuration as the conventional one, and does not particularly characterize the present invention.

FIG. 3 is a view for explaining the configuration of the clutch housing 12, and is a view showing a state in which the vibration-proof cover 17 is put on the outside of the cylindrical portion 12a. 3A is a plan view of the clutch housing 12 viewed from the bottom plate portion 12b side, and FIG. 3B is a cross-sectional view taken along the line BB in FIG. 3A.
As shown in FIG. 3B, a boss 19 is formed at the center of the bottom plate portion 12 b of the hook-shaped clutch housing 12. The driven shaft 4 (FIG. 1) is fixed to the boss 19. The bottom plate portion 12b is formed with six thinning holes 14 formed at regular intervals (that is, at intervals of 60 degrees around the driven shaft 4 corresponding to the rotating shaft). In addition, the code | symbol 20 in a figure shows the hole for rotation balance. Reference numeral 21 in the drawing indicates a spot welding position for fixing the vibration-proof cover 17 to the bottom plate portion 12 b of the clutch housing 12.
A plurality of convex portions 22 as shown in FIGS. 4 and 5 to be described later are formed on the inner peripheral side surface of the vibration-proof cover 17. In the present embodiment, the convex portion 22 corresponds to a positioning mark corresponding to the lightening hole 14.

On the other hand, FIG. 4 is a diagram illustrating the configuration of the vibration-proof cover 17 for covering the clutch housing 12. 4B is a plan view, and FIG. 4A is a cross-sectional view taken along the line AA in FIG. 4B.
As shown in FIGS. 4A and 4B and FIGS. 3A and 3B, the vibration-proof cover 17 according to this embodiment can press-fit the cylindrical portion 12a of the clutch housing 12. It is composed of a cylindrical side edge portion 17a and an annular bottom portion 17b formed in a size.
As shown in the drawing, the side edge 17a of the vibration-proof cover 17 has a total of three convex portions 22 that protrude to the inner surface side formed by pressing (that is, the outer surface side is recessed), that is, at equal intervals (that is, The driven shaft 4 is formed at intervals of 120 degrees.
FIG. 5 is a diagram illustrating the configuration of the vibration-proof cover 77 of another embodiment. FIG. 5B is a plan view, and FIG. 5A is a cross-sectional view taken along line AA in FIG.
The anti-vibration cover 77 according to this embodiment is similar to that shown in FIG. 4, and the cylindrical side edge 77a formed in a size capable of press-fitting the cylindrical portion 12a of the clutch housing 12 and the anti-vibration cover shown in FIG. 17 and an annular bottom 77b that is narrower than the bottom 17b. On the side edge 77a of the vibration-proof cover 77 according to this embodiment, a total of five protrusions 23 projecting toward the inner surface formed by pressing (that is, the outer surface is recessed) are equally spaced (that is, covered). The drive shaft 4 is formed at intervals of 72 degrees).

Next, assembly of the clutch housing having the above-described configuration (shape) and the vibration-proof cover will be described.
First, in the present embodiment, the vibration isolating cover 17 is arranged so that the circumferential position of at least one convex portion 22 that functions as a positioning mark substantially coincides with the position of at least one lightening hole 14 that also functions as a positioning mark. And the clutch housing 12 are positioned. Specifically, as shown in FIGS. 3 and 8, the anti-vibration cover 17 can be mounted by positioning the convex portion 22 of the anti-vibration cover 17 based on the position of the lightening hole 14.
That is, each convex portion 22 is arranged at substantially the same position as the corresponding hollow hole 14 with respect to the circumferential position of the inner surface of the vibration-proof cover 17. The vibration-proof cover 17 is placed on the clutch housing 12 and fixed at the relative position (that is, the clutch housing 12 is press-fitted and fixed inside the side edge portion 17a of the vibration-proof cover 17).

In carrying out the present invention, the position of the vibration node d and the position of the antinode e generated in the cylindrical portion 12a of the clutch housing 12 may be determined in advance by various analysis means. For example, this kind of analysis means includes vibration analysis based on a finite element method, vibration analysis based on a laser scanning vibration measurement method (laser Doppler vibration measurement), and the like.
The vibration analysis itself may be performed using a publicly available analysis program, and does not characterize the present invention, and thus detailed description thereof is omitted.

That is, in carrying out the present invention, the part (position) that becomes the node of vibration and the part (position) that becomes the antinode are determined in advance by various analysis means based on the shape, material, etc. of the target clutch housing. . A positioning mark may be appropriately formed according to the determined position.
For example, in the clutch housing cylindrical portion 12a according to the present embodiment having a shape as illustrated, as a result of obtaining the positions of the vibration nodes d and antinodes e by calculation based on the finite element method, as shown in FIG. The position of the vibration antinode e substantially coincides with the position of the lightening hole 14.
Accordingly, at least two (three in this case) convex portions 22 formed on the vibration-proof cover 17 are arranged at substantially the same position as the lightening holes 14 with respect to the circumferential position of the inner surface of the vibration-proof cover 17. By doing so, all the convex parts 22 can be made to contact with the said clutch housing cylindrical part 12a in positions other than the vibration node of the clutch housing cylindrical part 12a. In other words, in the present embodiment, all the contact portions (that is, the contact portion comprising the convex portion 22 and the cylindrical portion 12a of the clutch housing 12) are formed in the antinode portion of vibration.

  In addition, even if one convex part 22 corresponds to the position of the vibration antinode e (FIG. 6) of the clutch housing and the other convex parts 22 are slightly deviated from the antinode position, at least one convex part 22 is present. If it is in the position of an antinode or its vicinity (namely, if all the convex parts 22 are not in the position of a node), sufficient vibration suppression effect can be acquired.

7A and 7B, the side edge portions 17a and 77a between the convex portions 22 and 23 of the anti-vibration covers 17 and 77 are not completely true arcs but are centered on the rotation axis. Thus, the side edges 17a and 77a are loosened when they are pre-shaped in a shape (slowly curved surface) that is shifted inward from a virtual circle that connects the protruding ends of the convex portions. It is desirable to be molded so as to be deformed into a curved surface. For example, as a specific example of such gently curved side edge portions 17a and 77a (a shape approaching a polygon as a whole), a circle approaching a triangle having the three convex portions 22 shown in FIG. A circular shape approaching a pentagon having five convex portions 23 as apexes shown in FIG.
By adopting such a shape, as shown in FIG. 8 and FIG. 9 which is a partially enlarged view thereof, the convex portion 22 of the vibration-proof cover 17 and the outer surface of the cylindrical portion 12a of the clutch housing 12 are positioned as described above. A point contact portion, preferably a line contact portion 30 is formed between the two. A line contact portion, preferably a surface contact portion 40, is formed on both sides of the line contact portion 30 in the circumferential direction with a non-contact portion 50 between which the vibration isolating cover 17 and the clutch housing 12 do not contact each other. Since the contact surface is widened by the formation of the line contact portion 30 and the surface contact portion 40 (and the non-contact portion 50 between them), the vibration absorption energy is increased and the noise suppression effect is enhanced.

As mentioned above, although this invention was demonstrated by suitable embodiment, in implementation of this invention, various forms other than the above-mentioned embodiment can take.
For example, in the above-described embodiment, the anti-vibration cover having three or five convex portions has been described with reference to the drawings. However, the number of convex portions is not limited, and as long as the effects of the present invention can be achieved. There may be two or four or six or more. Further, in carrying out the present invention, it is sufficient that a contact portion having an anti-vibration effect is formed between the anti-vibration cover and the clutch housing, and the above-mentioned convex portion is either one of the anti-vibration cover and the clutch housing or It can be formed in both.

  Moreover, as long as it can function as a positioning mark, the form and the number are not limited. In the above-described embodiment, the lightening hole and the convex portion are employed as the positioning marks, but the invention is not limited to such a form. For example, specific unevenness may be provided at a position where the vibration-proof cover and the clutch housing face each other, or a line (slit) may be provided. Further, the surface of the vibration-proof cover and the clutch housing may be marked with a paint or a pattern.

As is clear from the above description, the present invention provides the following inventions (1) to (4).
(1). A cylindrical part whose inner surface is a sliding contact surface;
A substantially saddle-shaped clutch housing comprising a bottom plate portion covering one end of the cylindrical portion;
A rotating shaft that is coaxial with the cylindrical portion of the clutch housing and to which rotational force is transmitted by the clutch housing;
A centrifugal shoe that rotates around the rotation shaft to contact / separate the sliding contact surface to connect / disconnect to the clutch housing;
An anti-vibration cover over the outside of the cylindrical portion;
A centrifugal clutch comprising:
In the bottom plate portion of the clutch housing, a lightening hole is formed,
A centrifugal clutch, characterized in that a convex portion that presses against an outer surface of the cylindrical portion is formed on an inner surface of the vibration-proof cover.
(2). The centrifugal clutch as set forth in (1), wherein the convex portion is disposed at substantially the same position as the lightening hole with respect to a circumferential position of the inner surface of the vibration-proof cover.
(3). At least two convex portions are formed on the cylindrical side edge portion of the vibration-proof cover, and the side edge portion between two adjacent convex portions has an arc shape shifted inward from a true arc shape. (1) The centrifugal clutch according to (1).
(4). A cylindrical part whose inner surface is a sliding contact surface;
A substantially saddle-shaped clutch housing comprising a bottom plate portion covering one end of the cylindrical portion;
A rotating shaft that is coaxial with the cylindrical portion of the clutch housing and to which rotational force is transmitted by the clutch housing;
A centrifugal shoe that rotates around the rotation shaft to contact / separate the sliding contact surface to connect / disconnect to the clutch housing;
An anti-vibration cover over the outside of the cylindrical portion;
An assembly method of a centrifugal clutch comprising:
Obtain the vibration nodes and antinode positions of the cylindrical portion of the clutch housing accompanying the rotation of the centrifugal shoe by calculation,
An assembling method of a centrifugal clutch, wherein the anti-vibration cover is placed on the clutch housing so that the convex portion comes into contact with a position other than the node.

Thus, according to the invention of the above (1), the convex portion of the inner surface of the vibration-proof cover that covers the clutch housing is pressed against the outer peripheral surface of the clutch housing, and the radial displacement due to the vibration of the clutch housing is reliably suppressed, Generation of abnormal noise can be sufficiently prevented.
Further, according to the invention of (2) above, the position of the lightening hole for weight reduction formed in the bottom plate portion of the clutch housing usually becomes an antinode of vibration, so that the anti-vibration cover is in the vicinity of this position. By arranging the convex portion and pressing the clutch housing cylindrical portion from the outside, it is possible to reliably suppress the vibration of the cylindrical portion and sufficiently suppress the generation of abnormal noise.
Further, according to the invention of (3), the vibration-proof cover is in point contact with the clutch housing at the convex portion to suppress vibration, and is in line contact with the clutch housing at the arc portion between the adjacent convex portions. Contact the outer surface of the clutch housing over a wide area. Therefore, even if the position of the vibration antinode is shifted, the antinode can be reliably pressed by the number and arrangement of the lightening holes. Further, since the contact surface is widened, the vibration absorption energy is increased, and the noise suppression effect is enhanced.
Further, according to the invention of (4), the vibration of the cylindrical portion of the clutch housing is analyzed by, for example, the finite element method, and the position of the vibration node and the antinode along the circumferential direction is calculated to obtain a position other than the node. By covering the clutch housing while pressing the convex portion of the vibration-proof cover, the vibration of the clutch housing can be effectively suppressed.

  The present invention can be applied to various friction rotating devices having a sliding contact member intermittently friction-welded to an inner surface of a cylinder, in addition to a centrifugal clutch mounted on a vehicle.

It is sectional drawing which shows typically an example of the continuously variable transmission to which this invention is applied. It is explanatory drawing which shows the structure of the centrifugal shoe which concerns on one Embodiment, FIG.2 (B) is a top view of a centrifugal shoe. FIG. 2A is a cross-sectional view taken along line AA in FIG. It is explanatory drawing which shows the structure of the clutch housing which concerns on one Embodiment in the state in which the vibration proof cover was covered on the outer side of the cylindrical part. 3A is a plan view of the clutch housing as viewed from the bottom plate side, and FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. It is explanatory drawing which shows the structure of the vibration proof cover which concerns on one Embodiment. 4B is a plan view of the anti-vibration cover, and FIG. 4A is a cross-sectional view taken along the line AA in FIG. 4B. It is explanatory drawing which shows the structure of the vibration proof cover which concerns on other embodiment. FIG. 5B is a plan view of the anti-vibration cover, and FIG. 5A is a cross-sectional view taken along the line AA in FIG. FIG. 6A and FIG. 6B are diagrams schematically illustrating examples of vibrations of clutch housings having different shapes. FIGS. 7A and 7B are diagrams schematically illustrating the curved shapes of the gently curved side edges of the vibration-proof covers having different shapes. It is a top view which shows typically the state by which the anti-vibration cover was mounted | worn (covered) to the cylindrical part outer surface of the clutch housing which concerns on one Embodiment, and is a figure explaining a line contact part and a surface contact part. It is a principal part enlarged view of FIG. 1 is a side view showing a motorcycle according to an embodiment.

Explanation of symbols

2 Drive shaft 3 Drive sheave 4 Driven shaft 5 Driven sheave 6 Belt 6a Belt 7 Movable sheave 8 Fixed sheave 9 Movable sheave 10 Fixed sheave 11 Centrifugal clutch 12 Clutch housing 12a Cylindrical portion 12b Bottom plate portion 13 Centrifugal shoe 14 Meat hole 15 Hollow shaft 16 Carrier 17, 77 Anti-vibration cover 17a, 77a Side edge 17b, 77b Bottom 18 Spring 19 Boss 20 Hole for rotation balance,
21 Spot welding position 22, 23 Convex part 30 Line contact part 40 Surface contact part 50 Non-contact part 100 Motorcycle (scooter)
101 front fork 102 front wheel 103 handle 104 seat 105 continuously variable transmission 106 engine unit 107 rear wheel c clutch housing cylindrical part d node e belly

Claims (12)

A clutch housing comprising a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end of the cylindrical portion;
A rotating shaft that is coaxial with the cylindrical portion of the clutch housing and to which rotational force is transmitted by the clutch housing;
A centrifugal shoe that rotates around the rotation shaft to contact or separate from the sliding contact surface to connect or disconnect the clutch housing;
An anti-vibration cover over the outside of the cylindrical portion;
A centrifugal clutch comprising:
The clutch housing and the vibration-proof cover are
A contact portion that makes contact with each other and a non-contact portion that does not make contact with each other, and a positioning mark that positions the clutch housing and the vibration-proof cover at a predetermined relative position that prevents occurrence of abnormal noise,
A centrifugal clutch characterized by comprising: In the bottom plate portion of the clutch housing, a hole is formed,
The centrifugal clutch according to claim 1, wherein the lightening hole and the contact portion of the vibration-proof cover are positioned so as to be in a predetermined position. On the inner surface of the anti-vibration cover, a convex portion is formed in pressure contact with the outer surface of the cylindrical portion.
The centrifugal clutch according to claim 1, wherein the convex portion and the contact portion of the clutch housing are positioned so as to be in a predetermined position. In the bottom plate portion of the clutch housing, a hole is formed,
On the inner surface of the anti-vibration cover, a convex portion is formed in pressure contact with the outer surface of the cylindrical portion.
The centrifugal clutch according to claim 1, wherein the lightening hole and the convex portion are positioned so as to be in a predetermined position.   The centrifugal clutch according to claim 4, wherein the convex portion is disposed at substantially the same position as the lightening hole with respect to a circumferential position of an inner surface of the vibration-proof cover. At least two convex portions are formed on the cylindrical side edge portion of the vibration-proof cover,
The side edge portion between two adjacent convex portions of the vibration-proof cover has a shape shifted inward from a virtual circle connecting the projecting ends of the convex portions around the rotation axis. 3. The centrifugal clutch according to 3.   The contact portion of the clutch housing and the contact portion of the anti-vibration cover each include a line contact portion that makes line contact with each other and a surface contact portion that makes surface contact with each other. Centrifugal clutch.   The contact portion of any one of the contact portion of the clutch housing and the contact portion of the vibration-proof cover includes a convex portion that is in line contact with the other contact portion that is opposed to the contact portion. Centrifugal clutch. A clutch housing comprising a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end of the cylindrical portion;
A rotating shaft that is coaxial with the cylindrical portion of the clutch housing and to which rotational force is transmitted by the clutch housing;
A centrifugal shoe that rotates around the rotation shaft to contact or separate from the sliding contact surface to connect or disconnect the clutch housing;
An anti-vibration cover over the outside of the cylindrical portion;
A centrifugal clutch comprising:
The anti-vibration cover is
At least two contact portions that contact the clutch housing at positions other than vibration nodes of the clutch housing cylindrical portion, and non-contact portions that do not contact the clutch housing on both sides in the circumferential direction of the contact portions;
A centrifugal clutch characterized by comprising: A clutch housing having a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end of the cylindrical portion; a rotating shaft that is coaxial with the cylindrical portion of the clutch housing and to which rotational force is transmitted by the clutch housing; A centrifugal clutch comprising a centrifugal shoe that is connected to or disconnected from the clutch housing by rotating around a rotating shaft and coming into contact with or separating from the sliding contact surface, and a vibration-proof cover that covers the outside of the cylindrical portion. An assembly method,
As the clutch housing and the anti-vibration cover, a clutch housing and an anti-vibration cover having positioning marks for positioning the clutch housing and the anti-vibration cover at a predetermined relative position for preventing the occurrence of abnormal noise are prepared.
A centrifugal clutch assembly characterized in that the anti-vibration cover is placed on the outer side of the cylindrical portion of the clutch housing so that a contact portion that contacts each other while being positioned at the predetermined relative position and a non-contact portion that does not contact each other are provided. Method. A clutch housing having a cylindrical portion whose inner surface is a sliding contact surface and a bottom plate portion covering one end of the cylindrical portion; a rotating shaft that is coaxial with the cylindrical portion of the clutch housing and to which rotational force is transmitted by the clutch housing; A centrifugal clutch comprising a centrifugal shoe that is connected to or disconnected from the clutch housing by rotating around a rotating shaft and coming into contact with or separating from the sliding contact surface, and a vibration-proof cover that covers the outside of the cylindrical portion. An assembly method,
The clutch housing cylindrical portion is brought into contact with at least two positions other than the vibration node of the clutch housing cylindrical portion determined in advance, and is not in contact with the clutch housing cylindrical portion on both sides in the circumferential direction of the contact portion. A centrifugal clutch assembling method, wherein the anti-vibration cover is placed outside the cylindrical portion of the clutch housing so that a contact portion is provided. A vehicle comprising the centrifugal clutch according to claim 1.

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