JP2652466B2 - Silent chain - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silent chain, and more particularly, to reducing the torsion applied to a connecting pin by making the deformation of a guide link plate the same as the deformation of a link plate when a load is applied. The present invention relates to a silent chain that minimizes breakage of the chain.

[0002]

2. Description of the Related Art In general, in a silent chain in which a number of link plates are arranged side by side and in a longitudinal direction and connected by rocker pins, in order to prevent falling off from the sprocket when the chain is wound around the sprocket. A guide link plate a having a shape as shown in FIG. 7 is arranged at both ends or the center of a row of link plates arranged in the horizontal direction.

By the way, when a load is applied to the silent chain, a deformation moment acts in the direction shown by the arrow in FIG. 1 on the link plate, and the link plate has a concave portion defined by a pair of tooth portions. Attempts to deform as shown by the dashed line. However, since the conventional guide link plate a has no teeth and no concave portion as shown in FIG. 7, the deformation amount is smaller than that of the link plate. There is a problem that the rocker pin is easily bent and broken due to the difference in the amount of deformation between them.

As one conventional method for solving such a problem, as described in Japanese Patent Publication No. 51-1815, an outer edge (an edge opposite to a side where a concave portion of a link plate is formed) is provided. There is a method using a guide link plate provided with a concave portion. However, in this method, it is possible to make the amount of deformation of the chain in the pitch line direction the same, but since the deformation moment acting on the link plate and the deformation moment acting on the guide link plate are opposite, the resulting In addition, there is a problem in that the rocker pin is twisted, and the rocker pin is easily broken by the twist.

Another conventional method is disclosed in Japanese Patent Publication No.
As disclosed in Japanese Patent Application Laid-Open No. 821, a rocker pin is prevented from being broken by arranging one link plate inside each of the outer guide link plates. This is not a fundamental solution because it does not eliminate the rocker pin curvature based on the difference between the deformation amount and the deformation amount of the link plate. Moreover, in this case, since the link plate is added, there is a problem that the width and weight of the chain are increased even under the same allowable transmission load.

The present invention has been made to solve such a conventional problem, and an object of the present invention is to make the deformation of the guide link plate due to the load the same as the deformation of the link plate, thereby bending the link pin. An object of the present invention is to minimize stress and torsional stress to minimize breakage of a connecting pin and to prevent an increase in chain wear due to an increase in local contact pressure between the connecting pin and a link plate.

[0007]

In the silent chain according to the present invention, a number of link plates having a pair of teeth and a pair of pin holes are arranged in the lateral and longitudinal directions and inserted into the pin holes. In the silent chain in which the guide link plates are arranged in rows of the link plates in the horizontal direction while being connected by the connecting pins, a slit extending from the inner edge to the outer edge is formed in the guide link plate, It is characterized in that the end is formed in a curved shape.

[0008]

According to the present invention, when a load acts on the silent chain, the guide link plate extends by substantially the same amount as the link plate and bends in the same direction.
Therefore, the bending stress and the torsional stress acting on the connecting pin can be minimized, and the breaking of the connecting pin can be prevented.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a silent chain 1 according to a first embodiment of the present invention. As shown in FIG. 1, the silent chain 1 of this embodiment includes a link plate 2 having a pair of tooth portions 21 and a pair of pin holes 22 formed in a horizontal direction as shown in FIGS. A rocker joint 3 composed of rocker pins 31 and 32 is inserted into each pin hole in the longitudinal direction, and they are connected to each other. A guide link plate 4 having a shape as shown in FIG. It is arranged and the end of the longer rocker pin 31 is fitted and fixed to its guide link plate. Then, as in a normal silent chain, the rocker pins 31 are fixed to the link plates in the rows (FIG. 4) of the link plates 2a, and the rocker pins 32 are fixed to the link plates in the rows of the link plates 2b. This enables rocker joint rocking movement. In this embodiment, a rocker pin will be described as an example of a connecting pin. However, the present invention can be applied to a round pin.

The structure of the link plate and the rocker joint is the same as that of the prior art, and the feature of this embodiment lies in the structure of the guide link plate 4. That is,
In FIG. 3, the guide link plate 4 is the same as the one generally used in the related art in the point that an outer contour shape and a pair of pin holes 42 for rocker pins are formed. The difference is that one slit 48 extending toward the outer edge is formed. The end portion 49 of the slit 48 is formed in a curved shape to avoid stress concentration. The depth of the slit is determined so that when a load is applied to the silent chain 1, the guide link plate 4 extends by substantially the same amount as the link plate 2 and bends by the same amount in the same direction (the direction of the arrow in FIG. 1). Have been. Further, the width of the slit is made smaller than the tooth thickness of the sprocket so that the guide link plate retains the guiding function.

By setting the shape of the guide link plate 4 as described above, when a load is applied to the silent chain, the guide link plate becomes the link plate 2.
, And bend by almost the same amount in the same direction (the direction of the arrow in FIG. 1). Therefore, the rocker pin 31
And 32, the bending moment due to the difference in elongation between the guide link plate 4 and the link plate 2 can be prevented from acting, and the torsional moment can also be prevented from acting. Thereby, breakage of the rocker pin due to bending stress and torsional stress can be prevented.

FIGS. 5 and 6 show another embodiment. In this embodiment, the guide link plate 4 '
Are formed with two slits 48c extending obliquely from the inner edge 44 to the outer edge. The end 49c of the slit 48c is formed in a curved shape to prevent stress concentration. When a load acts on the silent chain 1 ', the guide link plate 4'
Are extended by substantially the same amount as the link plate 2 and are bent by the same amount in the same direction (the direction of the arrow in FIG. 1).

In the above configuration, when the silent chains 1 and 1 'are wound around a sprocket (not shown) to transmit power, the power is transmitted by the link plate 2, and the guide link plates 4 and 4' are connected to the sprocket by the silent chain. I will guide you so that you do not come off.
On the other hand, when a load is applied to the silent chain, the guide link plates 4, 4 'extend by substantially the same amount as the link plate 2, and bend in the same direction by receiving a deformation moment in the same direction (the direction of the arrow in FIG. 1). Therefore, bending stress and torsional stress hardly act on the rocker pin, and it is possible to prevent breakage due to these stresses.

[0014]

As described above, according to the silent chain according to the present invention, it is possible to prevent the rocker pin from breaking due to bending stress and torsional stress, and thus, it is possible to reduce the weight even in the same size as the conventional silent chain. A chain that can withstand a large load can be manufactured.

[Brief description of the drawings]

FIG. 1 is a front view of a link plate constituting a silent chain according to an embodiment of the present invention.

FIG. 2 is a partial plan view of the silent chain.

FIG. 3 is a front view of a guide link plate constituting the silent chain.

FIG. 4 is a front view of the silent chain.

FIG. 5 is a front view showing a modified example of the guide link plate.

FIG. 6 is a front view of a silent chain using the guide link plate (FIG. 5).

FIG. 7 is a front view of a conventional guide link plate.

[Explanation of symbols]

 1, 1 'silent chain 2 link plate 3 rocker joint 4, 4' guide link plate 48, 48c slit

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Koji Morishige, Inventor 1300-50, Ichino, Yawata-sha, Nabari-shi, Mie Borg Warner Automotive Co., Ltd. (56) Reference Reference )

Claims (1)

(57) [Claims] 1. A plurality of link plates having a pair of teeth and a pair of pin holes formed therein are arranged in a lateral direction and a longitudinal direction, and are connected by connecting pins inserted into the pin holes. In the silent chain having guide link plates arranged in rows, a slit extending from an inner edge toward an outer edge is formed in the guide link plate, and an end of the slit is formed in a curved shape. Silent chain to do.