JPH0155821B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a silent chain, and more specifically, it has a pair of long and short connecting pins each having an arcuate cross-sectional shape, and guides both ends of the long connecting pin. The present invention relates to a silent chain in which the shear strength of a connecting pin of a silent chain fixed by being fitted into a hole in a plate is increased.

(B) Prior Art As shown in Fig. 5B, a so-called lock joint type silent chain has a link plate a that has a pair of teeth b that mesh with the sprocket teeth and a pair of holes c at positions corresponding to the teeth. A plurality of pins are arranged in the horizontal direction as shown in Fig. 4, and a pair of long and short connecting pins d and e having an arcuate cross section as shown in Fig. 5C are inserted into the hole c. These link plates are connected, and guide plates f having no driving teeth as shown in FIG. It is constructed by being fitted and fixed within g.

By the way, in the construction of a lock joint type silent chain, it is essential that one of the pair of connecting pins is fixed to the guide plate while the other connecting pin is allowed to swing freely with respect to the guide plate. Conventionally, only one long connecting pin was fixed to the guide plate as described above.

On the other hand, when tension is applied to the silent chain, the link plates a are alternately pulled in opposite directions, so that shearing force acts on the connecting pins, producing shearing stress. The maximum value of this shear stress occurs where the effective cross-sectional area of the connecting pin is smallest, so in conventional silent chains, it is greatest at the root of the long connecting pin to the guide plate.

For this reason, in conventional silent chains, when a large load is applied, the long connecting pins break at the base, making the chain unusable.

(c) Problem to be solved by the invention The problem to be solved by the invention is to increase the tensile strength of a silent chain in an inexpensive manner by using guide plates and link plates in a stacked manner. .

(d) Means for Solving the Problems In order to solve the above problems, the present invention provides a plurality of link plates each having a pair of drive teeth that engage with the teeth of a sprocket and a pair of holes, which are inserted into the holes. In the silent chain, the guide is connected side by side in the horizontal and vertical directions by a pair of long and short connecting pins, and the ends of the long connecting pins are fitted and fixed into holes in guide plates arranged on both sides of the link plate. An auxiliary plate is stacked on the inside of the plate, and the ends of the short connecting pins are fitted into holes in the auxiliary plate.

(e) Operation When the silent chain having the above structure is connected endlessly and hung on a sprocket to operate the driving sprocket, power is applied to the silent chain, and the power is transmitted from the silent chain to the driven sprocket. Power is then transmitted to the silent chain. When tension is applied to the silent chain, a substantially equal shearing force is applied to the connecting pins as a whole.

(f) Examples Examples of the silent chain according to the present invention will be described below with reference to the drawings.

1 and 2, a silent chain 1 according to this embodiment is shown. In the figure, 2 is a link plate in which a pair of teeth 3 and a pair of holes 4 are formed, 5 is a guide plate in which a pair of arcuate holes 6 is formed, and 7 and 8 are rotatable with respect to each other in the hole 4. A long connecting pin (hereinafter referred to as long pin) and a short connecting pin (hereinafter referred to as short pin) are inserted, and their shapes are the same as the conventional link plate, guide plate, and connecting pin shown in FIG. A plurality of link plates 2 are lined up horizontally with a gap equal to the thickness of the link plate to form a horizontal row, and adjacent link plates are inserted into the gap to insert connecting pins 7 and 8 into the holes 4.
are inserted and connected in the lateral and longitudinal directions. Guide plates 5 are arranged every other row on both outer sides of the horizontal rows of link plates. In this way, rows with guide plates on both sides (hereinafter referred to as guide rows) and rows without guide plates (hereinafter referred to as link rows) alternate over the entire length of the silent chain.

In the present invention, an auxiliary plate 2a having the same shape as the link plate 2 is placed on the inner side of the guide plate and between the link plate on the outer side of the link row and overlaps the guide plate 5. The long pin 7 is fitted into the hole 6 of the guide plate and fixed by caulking the end. Further, the short pin is inserted into the hole 4a of the auxiliary plate 2a superimposed on the guide plate 5.

The silent chain 1 having the above structure is also connected to the driving and driven sprockets in the same manner as the conventional silent chain, and transmits power from the driving sprocket to the driven sprocket. When tension is applied to the silent chain, the link plates of the guide row and the link plates of the link row are pulled in opposite directions, so the long pin 7 and the short pin 8
A shear force acts on the In addition, near both ends of the long pin 7, two pins, a long pin and a short pin, are inserted up to the hole in the auxiliary plate, and conventionally, two pins, a long pin and a short pin, are inserted into the holes in the auxiliary plate, and the direction between the outermost link plate and the guide plate in the conventional link row is In the chain of the present invention, a shearing force approximately equal to the shearing force generated by tension is generated between the outermost link plate of the link row and the auxiliary plate, so the connecting pins that can withstand the shearing force are also made of long pins and short pins. Since there are two, the effective cross-sectional area is doubled. Therefore, the stress acting on the connecting pin becomes almost uniform, and the tensile strength also increases.

Note that almost no shearing force acts between the guide plate 5 and the auxiliary plate because they receive a tensile force in the same direction.

(g) Effects The silent chain according to the present invention can have the following effects.

Breakage at both ends of the connecting pins can be completely prevented, and the allowable tensile strength of the chain can therefore be increased to the shear strength of the two connecting pins.

The tooth width of the sprocket that engages with the chain can be increased by the amount of the auxiliary plate, and the sprocket teeth and strength can be increased by that amount.

Conventionally, the number of link plates in the guide row is one less than the number of link plates in the link row, so the contact pressure of the sprocket per link plate is higher than that of the link plate in the guide row, and the contact surface with the sprocket is This caused "burrs" and hindered the movement of the link plates in the link rows, which worsened the flexibility of the chain.However, with the present invention, the number of link plates can be the same in both the guide rows and the link rows, so the above problem can be improved. problems can be eliminated.

Since the link plate can be used as it is as an auxiliary plate, there is no need to make special parts and the cost can be reduced.

[Brief explanation of drawings]

FIG. 1 is a side view of a part of an embodiment of the silent chain according to the present invention, with a part of the guide plate removed, and FIG. 2 is a side view of a part of the silent chain according to the present invention.
- A sectional view along line A, Figure 3 is a side view of a part of a conventional link plate, Figure 4 is a line B-B in Figure 3.
FIG. 5 is a perspective view of a link plate, a guide plate, and a connecting pin of a conventional silent chain. 1, 1': silent chain, 2: link plate, 3: drive tooth, 4: hole, 5: guide plate, 6: hole, 7, 8: connecting pin.

Claims (1)

[Claims] 1. A plurality of link plates each having a pair of driving teeth and a pair of holes that engage with the teeth of a sprocket are connected side by side in the horizontal and vertical directions by a pair of long and short connecting pins inserted into the holes, and the long connection is made. In a silent chain in which the ends of the pins are fitted and fixed into the holes of guide plates arranged on both sides of the link plate, an auxiliary plate is arranged inside the guide plate to overlap the ends of the short connecting pins. A silent chain fitted into a hole of the auxiliary plate.