JPH09242849A - Pulley for transmission belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent interference between a side edge part on the slide contact side of a belt and a flange root part for reducing the end face wear of the belt. SOLUTION: An idler pulley is equipped with an about cylindrical pulley peripheral part 4, and the part 4 fitted on the outer periphery of a bearing 2 has flanges 3, 3 on both side edges. A recessed spot 7 for avoiding the hit to the side end edge 9 on the slide contact side of a belt 8 is severally formed in both crossing corner parts between the inside faces 6, 6 of both the flanges 3, 3 and the belt winding peripheral surface 5 of the pulley peripheral part 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission belt pulley, and more particularly, to an improvement of a transmission belt pulley having a belt disengagement prevention flange on at least one side edge of a pulley outer periphery for hanging a belt.

[0002]

2. Description of the Related Art Conventionally, there are transmission belt pulleys used for belt transmission, which are provided with a belt disengagement prevention flange on at least one side edge of the pulley outer periphery for hanging the belt. Belt pulleys are generally formed by casting, cutting, pressing or the like.
For example, FIG. 7A shows a flat belt pulley 5 having a substantially cylindrical pulley outer peripheral portion 54 manufactured by machining such as cutting.
1 is a partial cross-sectional view of FIG. 1, in which a pulley outer peripheral portion 54 fitted to the outer periphery of the bearing 2 has flanges 53, 53 on both side edges and forms a belt winding groove between both flanges 53, 53. . The belt winding groove has a width slightly wider than the width of the belt on which the belt is wound, and the groove bottom has a pulley outer peripheral portion 5
4 is the outer peripheral surface of the flat belt winding peripheral surface 55.

FIG. 7B is a partial sectional view of a flat belt pulley 61 having a substantially cylindrical pulley outer peripheral portion 64 manufactured by press working. The pulley fitted to the outer periphery of the bearing 2 is shown in FIG. The outer peripheral portion 64 has flanges 63,
63, and a belt winding groove is formed between both flanges 63, 63. The belt winding groove has a width slightly wider than the width of the belt to be stretched, and the groove bottom portion is a flat belt winding peripheral surface 65 which is the outer peripheral surface of the pulley outer peripheral portion 64.

Then, such a pulley outer peripheral portion 54 (6
4) inner flanges 56, 56 (66, 66) of both flanges 53, 53 (63, 63) and belt winding peripheral surface 55.
A corner surface 57 (67) intersecting with (65) is provided with a radiused surface having an appropriate curvature to prevent stress concentration at the flange root portion. Particularly, in the case of the pulley outer peripheral portion 64 formed by press working, the corner portion 67 of the flange root portion is formed due to the restriction of the minimum bending radius during press working.
Is required to have a rounded surface.

[0005]

However, the pulley outer peripheral portion 54 (6) having the corner portions 57 (67) as described above.
In the case of 4), as illustrated in FIG. 8 (only the flat belt pulley 51 is illustrated), the rounded surface of the corner portion 57 interferes with the sliding contact side edge portion 59 of the belt 58.
There is a problem in that the end surface wear of the belt 58 is affected, which is one of the causes of shortening the life of the belt 58. That is, although the rounded surface of the corner portion 57 is a very small rounded surface, the sliding contact side edge portion 59 of the belt 58 having a substantially right-angled edge portion is worn by being constantly brought into sliding contact with the corner portion 57. Will end up. Therefore, the object of the present invention is to solve the above problems, and to prevent interference between the sliding contact side edge portion of the belt and the flange root portion, and a good transmission belt capable of reducing wear of the end surface of the belt. Is to provide a pulley for use.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a transmission belt pulley having a belt disengagement prevention flange on at least one side edge of an outer peripheral portion of a pulley for hanging a belt. This is achieved by a pulley for a transmission belt, characterized in that a recess for escaping the contact with the sliding contact side edge of the belt is formed at a corner where the outer peripheral surface of the pulley outer peripheral portion intersects. .

Preferably, the recess is provided on at least one of the inner surface side of the flange and the outer peripheral surface side of the pulley outer peripheral portion. That is, according to the above configuration, it is possible to increase the curvature rate of the corner portion and prevent the contact between the corner portion and the sliding contact side edge of the belt.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A transmission belt pulley according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a partial sectional view of an idler pulley 1 according to a first embodiment of the present invention, and FIG. 2 is an enlarged sectional view of its essential part.

The idler pulley 1 has a substantially cylindrical pulley outer peripheral portion 4 which is manufactured by cutting, casting, sintering or the like.
The pulley outer peripheral portion 4 fitted to the outer periphery of the bearing 2 has flanges 3 and 3 on both side edges, and forms a belt winding groove between the flanges 3 and 3. The belt winding groove has a width slightly wider than the width of the belt 8 to be stretched, and the groove bottom has a flat belt winding peripheral surface 5 which is the outer peripheral surface of the pulley outer peripheral portion 4. Further, at both corners where the inner side surfaces 6 and 6 of both the flanges 3 and 3 and the belt winding peripheral surface 5 of the pulley outer peripheral portion 4 intersect, the sliding contact side end edge 9 of the belt 8 is contacted. Recessed recesses 7 are formed respectively.

As shown in FIG. 2, the recess 7 is a groove formed continuously at the inner root of the flange 3 along the circumferential direction of the pulley outer peripheral portion 4, and the inner surface 6 of the flange 3 and the belt winding. It is formed by a smoothly curved surface having a large curvature that does not have any corners or steps with respect to the circumferential surface 5. The recess 7 is provided on the inner surface 6 side of the flange 3,
It has a cross-sectional shape that is recessed in the axial direction from the contact portion 6 a of the inner surface 6 of the flange 3 with respect to the belt 8. That is, in FIG. 2, there is a recess 7 at a position recessed to the left in the axial direction with respect to the extension line A of the inner surface 6 of the flange 3.

The height TR from the belt winding peripheral surface 5 to the outer peripheral end 7a of the recess 7 is larger than the thickness of the belt 8 so that the side end of the belt 8 does not enter the recess 7. Set low. Therefore, in the case of the first embodiment, the belt 8
Is a toothed belt having corrugated teeth 8a as shown in FIG. 3, the height TR from the belt winding peripheral surface 5 to the outer peripheral end 7a of the recess 7 is the tooth height T2 of the belt 8. Set lower than. Further, as long as the stress concentration in the recess 7 can be prevented, as shown in FIG.
However, it is preferable that it is set lower than the root height T1 of the belt 8.

That is, the root portion of the flange 3 is provided with a recess 7 for escaping the contact with the sliding contact side end edge 9 of the belt 8, and the inner side surface 6 and the outer peripheral surface 5 are formed. The sliding contact side edge 9 does not interfere with the intersecting corner. As a result, in the idler pulley 1 according to the first embodiment, the end surface wear of the belt 8 can be reduced and the life of the belt 8 can be extended. Further, due to the presence of the recess 7, the curvature at the intersection of the inner side surface 6 of the flange 3 and the belt winding peripheral surface 5 can be made large, and the stress concentration at the flange root portion can be relaxed. Although the idler pulley 1 for toothed belts having both flanges has been described in the above embodiment, the present invention is not limited to this, and a pulley having only one flange or a general pulley. Needless to say, the present invention can be applied to pulleys for transmission belts (for example, V belts, poly V belts) such as drive pulleys.
Needless to say, the shape of the recess may be various according to the gist of the present invention.

FIG. 4 is a partial sectional view of an idler pulley 11 according to the second embodiment of the present invention. The idler pulley 11 is provided with a substantially cylindrical pulley outer peripheral portion 14 manufactured by press working, and the pulley outer peripheral portion 14 fitted to the outer periphery of the bearing 2 has a flange 13 on one side edge. There is. The outer peripheral surface of the pulley outer peripheral portion 14 is a flat belt winding peripheral surface 15.

Further, at a corner where the inner side surface 16 of the flange 13 and the belt winding peripheral surface 15 of the pulley outer peripheral portion 14 intersect, a recess for escaping the contact with the sliding contact side end edge 9 of the belt 8. 17 are formed. The recess 17 is a recess that is continuous in the circumferential direction of the pulley outer peripheral portion 14, and has a large curvature that is smoothly continuous with the inner surface 16 of the flange 13 and the belt winding peripheral surface 15 without any corners or steps. It is formed by a curved surface. Further, like the recess 7 of the first embodiment, the recess 17 is provided on the inner surface 16 side of the flange 13.

Therefore, the idler pulley 11 of the second embodiment is similar to the recess 7 of the first embodiment described above in that the belt 8 is
Wear of the belt 8 can be reduced and the life of the belt 8 can be extended. Further, the presence of the recess 17 allows a large curvature at the intersection of the inner side surface 16 of the flange 13 and the belt winding peripheral surface 15, so that the stress concentration at the root of the flange can be alleviated and the press The bending radius at the time of processing becomes large and press working becomes easy. Further, in the idler pulley 11 of the second embodiment, since the recesses 17 are integrally formed at the same time as the flange 13 by the press working, the working cycle time becomes longer and the manufacturing cost does not rise due to the increase in the working man-hour. .

FIG. 5 is an enlarged sectional view of an essential part of the pulley outer peripheral portion 24 according to the third embodiment of the present invention. Outer part of pulley 2
In No. 4, in order to escape the contact with the sliding contact side edge of the belt, the recess 27 formed at the corner where the inner side surface 26 of the flange 23 and the outer peripheral surface 25 of the pulley outer peripheral portion 24 intersect is formed. The belt winding peripheral surface 25, not the inner surface 26 side of 23.
Is formed on the inner side of the extension line B of the belt winding peripheral surface 25.

FIG. 6 is an enlarged cross-sectional view of an essential part of the pulley outer peripheral portion 34 according to the fourth embodiment of the present invention. Outer periphery of pulley 3
4, the recess 37 is provided at the corner where the inner side surface 36 of the flange 33 and the outer peripheral surface 35 of the pulley outer peripheral portion 34 intersect so as to escape the contact with the sliding contact side edge of the belt. Inner side surface 36 and outer peripheral surface 35 of the pulley outer peripheral portion 34
Is formed diagonally over the inner surface 36 of the flange 33.
Is located outside the extension line A and inside the extension line B of the belt winding peripheral surface 35. The recess 2
In the case of forming a complicated shape such as 7, 37, for example, the manufacturing cost by forming the recesses 27, 37 by forming the pulley outer peripheral portions 24, 34 by sintering or casting (including die casting) Can suppress the rise of.

[0018]

As described above, according to the transmission belt pulley of the present invention, the sliding contact side edge of the belt is formed at the corner where the inner surface of the flange and the outer peripheral surface of the outer peripheral portion of the pulley intersect. A recess is formed to escape the contact with. Therefore, the sliding contact side end edge of the belt having the substantially right-angled edge does not interfere with the flange root portion, so that the end surface wear of the belt can be reduced and the life of the belt can be extended.
Further, due to the presence of the recess, the curvature at the intersection of the inner surface of the flange and the belt winding peripheral surface can be increased, and the stress concentration at the root portion of the flange can be relaxed.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of an idler pulley according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the idler pulley shown in FIG.

FIG. 3 is a vertical cross-sectional view of the belt shown in FIG.

FIG. 4 is a partial sectional view of an idler pulley according to a second embodiment of the present invention.

FIG. 5 is an enlarged cross-sectional view of an essential part of a pulley outer peripheral portion according to a third embodiment of the present invention.

FIG. 6 is an enlarged sectional view of an essential part of a pulley outer peripheral portion according to a fourth embodiment of the present invention.

FIG. 7 is a cross-sectional view of a main part of a conventional flat belt pulley,
(A) is a sectional view of a pulley manufactured by processing such as cutting,
(B) is a sectional view of a pulley manufactured by press working.

FIG. 8 is an enlarged sectional view of an essential part showing the relationship between a conventional pulley and a belt.

[Explanation of symbols]

 1 Idler pulley 3 Flange 4 Pulley outer peripheral portion 5 Belt winding peripheral surface 6 Inner side surface 7 Recess 8 Belt 9 Sliding contact side edge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sai Sai Sai 1203 Kamijima, Namekawa City, Toyama Prefecture Shinwa Industry Co., Ltd.

Claims (1)

[Claims] 1. A transmission belt pulley having a belt slip-off preventing flange on at least one side edge of an outer peripheral portion of a pulley for hanging a belt, wherein an inner surface of the flange intersects an outer peripheral surface of the outer peripheral portion of the pulley. A pulley for a transmission belt, characterized in that a concave portion is formed in a corner portion to escape from a contact with an end edge on the sliding contact side of the belt.