JPH0246340A - Link plate slip-off preventing process method for connecting pin in friction transmitting chain and device therefor - Google Patents

Abstract

PURPOSE:To facilitate calking and secure the sufficient expanded overhand quantity by providing theft holes at both end surfaces of the finest connecting pin of a link plate and having both end surfaces expansively deformed outward by the outer pressing force and calked. CONSTITUTION:After theft holes 2 being bored at the center of both end surfaces, a sheet pin 1 is subjected to the hardening process of its entire surface in order to highten its abrasion resistance, then only both ends 1' of the sheet pin 1 are part heated and annealed. The sheet pin 1 is pierced through a link plate, and the protruded ends are pressed in the direction of the pin axis by having seat metals 3 fixed into both ends 1' so as to be plastic deformed and calked. As both ends of the calked sheet pin 1 are squeezed outward from the periphery of the theft holes 2, the material of the squeezed part is plastic deformed and pushed out so as to form expanded overhand parts 1''.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a friction transmission chain used in continuously variable transmissions and the like.

Conventional technologyAs a friction transmission chain for continuously variable transmission, the patent application 1986-
As disclosed in the specification and drawings of No. 146958, an endless chain is inserted into the left and right spaces of a large number of overlapping I-shaped friction plates, and the upper and lower beam portions of the I-shaped friction plates are attached to the upper and lower sides of the link plate of the chain. A PJ friction transmission chain is exemplified in which the lower beam part is fitted into a recessed groove and both outer surfaces of the lower beam part are formed into V-shaped friction transmission surfaces that frictionally engage with the conical transmission surfaces of the ■-shaped pulley. As disclosed in Japanese Unexamined Patent Publication No. 62-146044 (specification and drawings of Utility Application No. 61-33779), the so-called "center misalignment" occurs in which the center line of the chain is displaced during gear shifting.

Due to this misalignment, a large lateral force acts on the chain transmitting power in the axial direction of the connecting pin of the transmission chain, and this lateral force becomes a force that pulls out the link plate from the connecting pin, connecting the link plate. This will cause it to detach from the pin and disassemble the chain.

Therefore, in the invention described in the above-mentioned Japanese Patent Application No. 63-146958, washers are press-fitted into both ends of the seat pin of the rocker joint type connecting pin, and the link plate falls out from the connecting pin due to the press-fitting locking force. It was preventing that.

Problems to be Solved by the Invention However, in a friction transmission chain for continuously variable transmission of an automobile, the tensile load applied to the chain is usually a large load of 1 ton or more, and therefore the lateral force caused by misalignment is large. Since this is an extremely large force, it is difficult for the press-fit locking force of the washer alone to provide a locking function against this extremely large lateral force, and accidents often occur when the chain disintegrates during gear shifting operations. Was.

Furthermore, the average thickness of each link plate of a friction transmission chain for automobile transmission is 1.2+u+, and the height is 8.4+m.
Since it is an extremely thin and small plate material called ■, the seat pin with a crescent-shaped cross section into which the washer is press-fitted has a maximum diameter of approximately 3.7+ms and a minimum diameter W of approximately 1.7 ms. hs
Since the pin is extremely thin (+), when an external pressing force is applied to caulk both end faces of the seat pin, the seat pin is bent and deformed, which impedes transfer contact with the rocker pin. Odor within specified dimensions
In order to increase the thickness of the link plate in order to increase the strength of the chain, the amount of protrusion from the washer at both ends of the seat pin is made as small as possible, so the amount of outward deformation caused by caulking is also minimal. However, it has been difficult to secure a sufficient extension amount to prevent the link plate from separating from the connecting pin against the lateral force caused by the above-mentioned misalignment.

Therefore, it is technically difficult to caulk both ends of the seat pin to prevent the connecting pin from coming off.
It was believed that the effect of caulking to prevent the connecting pin from coming off could not be expected.

The present invention solves the above-mentioned problems, facilitates caulking of both ends of a seat pin, secures a sufficient amount of extension, and prevents the connecting pin from coming off.

Means for Solving the Problems The present invention provides for drilling holes in both end faces of a connecting pin (seat pin), and pressing both end faces with the tapped holes in the axial direction of the connecting pin by an external force. A caulking process is performed to form an extended overhang, and the extended overhang prevents the link plate from coming off the connecting pin.

Operation: By drilling holes on both end faces of the connecting pin, the connecting pin can easily undergo extensional plastic deformation outward from the vicinity of the hole without applying an excessive caulking external force that would cause bending deformation of the connecting pin on both end faces. If the extensional plastic deformation is sufficiently performed, the amount of extensional overhang will also become large.

When the amount of extension and overhang becomes large, the link pin can overhang outwardly beyond the outline of the connecting pin insertion hole penetrated through the washer, so even if lateral force is applied to the link plate due to misalignment, the link plate This makes it possible to sufficiently prevent the force trying to separate from the connecting pin by the end portion of the connecting pin, thereby exerting the effect of preventing the connecting pin from coming off.

Example Fig. 1 is a front view of the main part of the friction transmission chain, Fig. 2 is an enlarged end view of the seat pin before caulking, and Fig. 3 is a side sectional view of the end of the seat pin before caulking. FIG. 4 is a side view of the end of the seat pin after caulking.

After the seat pin 1 has a hole 2 drilled in the center of both end faces, the entire surface is hardened to increase wear resistance, and then only the both ends 1' of the seat pin 1 are partially heated and annealed. , the pin is inserted into the link plate, and washer 3 is fitted into both ends 1', and both protruding end surfaces are pressurized in the axial direction of the pin to plastically deform it, and crimping is performed.

As shown in Fig. 4, both ends of the caulked seat pin 1 are crushed outward from the periphery of the hole 2, and the material of the crushed portion is plastically deformed and outwards. It flows and forms an extended overhang. The extended overhang part B shown in FIG.
Pressure is applied in this direction using a roof-shaped punch mold with a convexly curved pressing surface.

In addition, in the above embodiment, the caulking process was performed on both ends of the seat pin of a rocker joint type connecting pin, but a similar caulking process can also be applied to a round rod type connecting pin with a circular cross section by providing a hole in the center of both end faces. It is processed.

Effects of the Invention The present invention has a connecting pin of a friction transmission chain having an extremely thin cross-sectional dimension, and enhances the tensile strength of the chain within the width regulation dimension of the chain inserted into the left and right spaces of the friction plate having an I-shaped cross section. Because of this, it is necessary to maximize the thickness of the link plate, and the protruding portions at both ends of the connecting pin are limited to extremely short protruding lengths, so both ends of the connecting pin have dimensions that are extremely disadvantageous for caulking. However, by drilling a hole in the center of both end faces of the connecting pin, it is possible to easily plastically deform the connecting pin outward without applying large caulking pressure in the axial direction of the connecting pin, resulting in an ultra-thin connecting pin. At the same time, a small amount of material at both ends of the connecting pin having a short protrusion length is effectively extended outward around the hole to form an overhanging part for preventing the link plate from coming off. This has solved the problem of the extremely difficult caulking of both ends of the connecting pin in conventional friction transmission chains, and has been able to fully absorb the lateral pressure caused by misalignment during gear shifting. This eliminates the drawback that the link plate separates from the connecting pin and the chain disintegrates, and the effect is significant.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view of the main part of a friction transmission chain having a rocker joint type connecting pin, and FIG. 2 is an enlarged end view of the seat pin before caulking of the rocker joint type connecting pin. FIG. 3 is an enlarged side sectional view of the end of the seat pin before caulking, and FIG. 4 is an enlarged side view of the end of the seat pin after caulking. ...Connecting pin (seat pin) ′...Connecting pin (seat pin) end''...Extended overhanging part...Stealing hole...Washer Fig. 1 Fig. 2 Fig. 3

Claims (2)

[Claims] (1) Insert an endless chain into the left and right spaces of a large number of overlapped I-shaped friction plates, and engage the upper and lower beam portions of the I-shaped friction plates into the grooves formed in the upper and lower sides of the link plate of the chain. In addition, in a friction transmission chain in which both outer surfaces of the lower beam part are formed into V-shaped friction transmission surfaces that frictionally engage with the conical transmission surfaces of the V-shaped pulley, there are tapped holes in both end surfaces of the ultra-thin connecting pin of the link plate of the endless chain. A method of processing a link plate of a connecting pin to prevent it from coming off, in which both end surfaces are expanded and deformed outwardly by an external pressing force in the axial direction and caulked. (2) Insert endless chains into the left and right spaces of the I-shaped cross-section friction plates that are stacked together, and engage the upper and lower beam portions of the I-shaped friction plates into grooves formed in the upper and lower sides of the link plates of the chain. At the same time, in a friction transmission chain in which both outer surfaces of the lower beam part are formed into V-shaped friction transmission surfaces that frictionally engage with the conical transmission surfaces of the V-shaped pulley, both end surfaces of the ultra-fine connecting pin of the link plate of the endless chain are caulked. Link plate retaining device for connecting pins.