JPH0538547A - Manufacture of belt for chain type power conduction - Google Patents

Abstract

PURPOSE:To provide manufacturing method of belt for chain drive power transmission, in which cylinder part of tip body can be easily fitted to tip part of a pin and is not detached from the pin. CONSTITUTION:This manufacturing method for the belt, contains processes for connecting link plate 10, 20 group in the longitudinal direction as freely bending with pins and fitting the tip body having end face contacting with pulley wall face to both end parts 31 of the projecting pin from outer link plate positioned at the most outer side. The cup shaped tip body composed of a cylinder part 42 having at least two or more of notched parts 41 and a pulley abutting part 43 connected with the cylinder part, is heated at 200-400 deg.C, and after enlarging inlet of the above cylinder part 42, the tip body is pressed into both end parts 31 of the projecting pin from the outer link plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a chain type power transmission belt, and more particularly to a method for manufacturing a chain type power transmission belt in which the method of fitting a chip body in contact with a wall surface of a pulley into a pin is improved.

[0002]

2. Description of the Related Art Today, rubber V belts, metal chains and metal belts have been proposed as high load transmission belts applied to continuously variable transmissions of automobiles. Among them, the metal chain belt has a structure in which a plurality of link plate groups are flexibly coupled by pins, and a V-shaped block having a tapered surface that comes into contact with the V-belt is fitted between the pins. JP-A-57-22442, JP-A-59-226729 or JP-A-59-2267.
No. 30, for example.

Further, as a belt of the same kind, a belt in which both ends of a pin for connecting a group of link plates are tapered surfaces to be engaged with a wall surface of a V-pulley is, for example, Shoukai 63-37846.
This type of belt is known to transmit sufficient power by increasing the diameter of the pin.

As another chain belt, a freely movable tip body is attached to both ends of a pin connecting a plurality of link plate groups as disclosed in Japanese Patent Laid-Open No. 63-2119937. Also known is a belt that adapts the end surface of the tip body to the side wall of the pulley when the belt enters the pulley and rotates the tip body itself to reduce vibration, rolling or collision when the belt enters the pulley. Therefore, trials for practical use are in progress.

[0005]

However, among the above belts, the chain type belt in which the tip body is attached to both ends of the pin is designed so that the tip body slightly swivels around the pin. Especially when the belt moves in and out of the pulley under the condition of high load transmission, the lateral pressure applied to the contact line between the side wall of the V pulley and the chip body or the pulling force in the longitudinal direction of the belt is different on this contact line. The particles are dispersed and generate a rotational moment on the tip body, so that the tip body actively tries to rotate. As a result, it has been clarified that the collision noise between the pulley and the tip body when the belt enters the pulley is greatly reduced.

However, while such a chain type belt has such effects, a method for fitting the tip body to the tip portion of the pin has not been sufficiently established. For example, as one of the methods, there is a shrink fitting method in which a tip body expanded by heating is press-fitted into the tip portion of a pin. However, in this method, since the tip body is metallic and its expansion coefficient due to heating is small, it must be forcibly pressed in, and the tip body is deformed in the direction of expansion during press-fitting and the tip body is damaged. In addition, there is a big problem that the chip body separates from the pin.

The present invention solves the above problems in particular, and manufactures a chain type power transmission belt in which the tubular portion of the tip body can be easily fitted to the tip end portion of the pin and is not detached from the pin. The purpose is to provide a method.

[0008]

That is, in the present invention, a link plate group is flexibly connected in the longitudinal direction by a pin, and a pulley wall surface is formed at both ends of the pin protruding from the outermost outer link plate. A method for manufacturing a chain type power transmission belt including a step of fitting a tip body having contacting end faces, which is a cap-like shape including a tubular portion having at least two notches and a pulley abutting portion connected to the tubular portion. The tip body is heat-treated at 200 to 400 ° C. to enlarge the inlet of the cylindrical portion, and then press-fitted into both ends of the pin protruding from the outer link plate. Further, the tip body is provided with a plurality of kerfs penetrating at regular intervals along the circumferential direction of the central portion in the longitudinal direction of the rod-shaped body, and then the central portion is cut to form a recessed portion on the cut surface. It is obtained by providing.

[0009]

According to the manufacturing method of the present invention, the chip body having at least two notches in the cylindrical portion is provided at 200 to 400 °.
When heated at a relatively low temperature of C, the inlet of the tubular portion having the cut portion uniformly expands due to thermal expansion, and the chip body can be easily press-fitted into both ends of the pin. The surface treatment of the chip body does not have to be destroyed. Moreover, the cylindrical portion of the chip body is fitted to both ends of the pin by the elastic force, and the grip force is large, so that the pulling force between the chip body and the pin is large.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a partial perspective view of a chain type power transmission belt obtained by the method of the present invention, and FIG. 2 is A of FIG.
FIG. In the chain type power transmission belt 1, a plurality of main link plates 10 arranged in parallel at predetermined intervals in the belt width direction, and other substantially the same shape arranged between these main link plates 10. The sub-link plate 20 and the sub-link plate 20 are connected by the pins 30 into which the through-holes 11 and 21 are inserted in a state where the through-holes 11 and 21 provided on both sides thereof are aligned with each other so as to be bendable in the belt longitudinal direction, It is configured endlessly.

A tip body 40 engaging with the wall surface of the V-pulley is fitted to the spherical end 31 of the pin protruding from the outer wall 12 of the so-called outer link plate outside the belt 1. The chip body 40 includes a tubular portion 42 having at least two notches 41 and a pulley contact portion 43.
It is a cap body consisting of. The end of the pulley contact portion 43 is flat, conical, or frustoconical.

Since the tip body 40 encloses the cylindrical portion 42 in the spherical end portion 31 of the pin, the spherical end portion 3 of the pin is formed.
It is easy to make a slight movement on one surface, and the cylindrical portion 42 engages with the spherical end portion 31 of the pin to increase the grip force, so that the tip body 40 is prevented from coming off.

Next, an embodiment of the present invention will be described with reference to FIGS. In the manufacturing method of the present invention, the belt 1
After the main link plate 10, the sub-link plate 20, the pins 30, and the chip body 40, which are the components of the above, are manufactured in advance, these parts are assembled into a finished product. Chip body 40 and pin 3
Insertion with 0 becomes important. First, as shown in FIG. 3, a method for manufacturing the chip body 40 is as follows. A circular kerf 46 penetrating the central portion in the longitudinal direction of a rod-shaped body 45 having a circular cross section having a predetermined length is formed at regular intervals along the circumferential direction. After providing a plurality of pieces, the central portion is cut to separate into two pieces. Then, it is obtained by cutting the cut surface into a spherical recess 44 by machining.

As shown in FIG. 5, the obtained tip body 40 has a cap body shape consisting of a tubular portion 42 having a plurality of notches 41 and a pulley contact portion 43 protruding from the tubular portion 42. Has a spherical recess 44. The inner diameter of the inlet 47 of the tip body 40 is larger than the maximum diameter of the spherical end portion 31 of the pin by about 0.1 to 0.14 mm, so that the tip body 40 can be easily fitted into the end portion 31. Further, each component including the chip body 40 is subjected to nitriding treatment, boron treatment, or the like in order to increase the surface hardness.

Therefore, in the present invention, the tip body 40 can be easily fitted into the spherical end portion 31 of the pin, and the tip body 4 can be easily inserted.
It is important to improve the pulling force of 0 from the end portion 31. In this method, first, the chip body 40 is
When the heat treatment is performed at 0 to 400 ° C., preferably 300 to 350 ° C., the tubular portion 42 having the plurality of cut portions 41 uniformly expands and expands outward, and the diameter of the inlet 47 increases. If the cutout portion 41 is not provided, the tubular portion 42 does not expand sufficiently at the above temperature. On the other hand, the heating temperature is 40
If the temperature exceeds 0 ° C, the bond of the nitride in the surface layer of the chip body 40 is likely to be broken, and the surface hardness may be lowered. While the chip body 40 thus heated is not cooled, it is press-fitted into the spherical end 31 of the pin and fitted therein.

In the present invention, the cylindrical portion 4 of the chip body 40
Providing a plurality of notches 41 in 2 is important for uniformly expanding the inlet 47 of the tubular portion 42 at a relatively low temperature. The number of the cut portions 41 is preferably 4-8. When the number is nine or more, the grip force of the tubular portion 42 becomes small, and the pulling-out force between the tip body 40 and the spherical end portion 31 of the pin starts to decrease. On the other hand, if the number is three or less, the inlet 47 of the tubular portion 42 is less likely to expand, and a considerable pressing force is required during hot press fitting, so that cracks are likely to occur from the end of the cut portion 41. Further, as the heating temperature is raised, the expansion rate of the cylindrical portion 42 is increased, but the surface treatment of the chip body 40 is destroyed as described above.

[0017]

As described above, in the method for manufacturing the chain type power transmission belt of the present invention, the inlet of the cylindrical portion of the chip body having at least two notches is uniformly expanded at a relatively low temperature. In addition, since it can be easily press-fitted into the spherical end portion of the pin to be fitted, the hardness of the surface layer of the chip body does not decrease, and the grip force is generated by the elastic force of the cylindrical portion of the chip body. It also has the effect that the chip body does not easily come off. In the second aspect, in the chip body, it is possible to easily manufacture the tubular portion having the cut portion.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a chain type power transmission belt using a chip body obtained by a manufacturing method of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory view showing a manufacturing process of a chip body.

4 is an explanatory view showing a manufacturing process of a chip body following the process of FIG.

FIG. 5 is a perspective view of a chip body used.

[Explanation of symbols]

 10 Main Link Plate 20 Sub Link Plate 30 Pins 31 Pin Spherical End of Pin 40 Chip Body 41 Notch 42 Cylinder 43 Pulley Abutment 47 Inlet

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masaki Nonaka 4-1-21, Hamazoe-dori, Nagata-ku, Kobe City Mitsusei Belt Co., Ltd. (72) Inventor Hiroyuki Hasegawa 4-1-21, Hamazoe-dori, Nagata-ku, Kobe Mitsuboshi Belting Co., Ltd. (72) Inventor Tomizo Kanaoka 4-1-21, Hamazoe Dori, Nagata-ku, Kobe Mitsuboshi Belting Co., Ltd.

Claims (2)

[Claims] 1. A step of connecting a group of link plates flexibly in a longitudinal direction by a pin, and fitting a chip body having an end surface in contact with a pulley wall surface to both ends of a pin protruding from an outermost outer link plate. In a method for manufacturing a chain type power transmission belt including: a cap-shaped tip body having a tubular portion having at least two or more notches and a pulley contact portion connected to the tubular portion;
A method for manufacturing a chain type power transmission belt, which comprises heat-treating at ° C to enlarge the inlet of the cylindrical portion, and then press-fitting this into both ends of a pin protruding from the outer link plate. 2. A plurality of kerfs are formed at regular intervals along the circumferential direction of the center of the rod-shaped body in the longitudinal direction, and then the center is cut to form a recess in the cut surface. 2. The method for manufacturing a chain type power transmission belt according to claim 1, wherein the chip body is obtained by providing.