JPS58652A - Jointing method of belt - Google Patents

Abstract

PURPOSE:To joint a belt without causing the decrease of load capability in end parts of the belt, by mating the end parts of the recessed belt at a face-to- face position, inserting an almost strip-shaped connecting strip into a hollowed place and heating the end part under pressure. CONSTITUTION:Both jointed end parts 3, 4 of a belt are placed at a face-to-face position, and a space 9 is formed by both hollowed parts 6, 6, then an almost stripe-shaped connecting strip 10 is inserted into said space 9. The both junction end parts 3, 4 and the connecting strip 10 are mutually welded by a heating means under pressure to joint the end part of the belt.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a belt joining method in which both ends of an end belt are joined to each other to form an endless belt tracker, and more specifically, the present invention relates to a belt joining method that is easy to work with and has a high strength at the joined portion. The present invention provides a joining method.

For example, toothed belts made of urethane rubber are widely used as timing belts for automobile engines. In order to increase the tensile strength, reinforcing cords of steel wire, fibers, etc. are usually embedded.

As an economical manufacturing method for this type of belt,
A method is used in which a long bell (Y) is formed by the method described in Japanese Patent No. 654, etc., cut to a required length, and both ends are abutted and fused together to make it endless. in this case,
It is required that the load capacity for tensile load or bending load during driving of the joint part does not decrease significantly compared to the load capacity of the non-joint part.

The technique described below is disclosed in Japanese Patent Application Laid-Open No. 49-93755 as a belt joining method that takes into account the maintenance of the load capacity at the above-mentioned joints. As illustrated in FIGS. 1 and 2, the method for joining belts disclosed in the publication is as follows:
A protrusion 5 and a recess 6 are provided in each of the joint ends so that the protrusion of one joint end and the recess of the other joint end are aligned with each other, and both joint ends 3.4 are brought into contact with each other and bonded. Although they are joined to each other by means such as fusion, the load capacity at the joint is such that a portion of the reinforcing cord 7 is cut off at the cross section a-a of the abutment between the end face of the protrusion 5 and the bottom face of the recess 6. cross section a −
In the embodiment shown in FIG. 1, in which the number of reinforcing cords cut at (a) corresponds to 215 of the total number of reinforcing cords, the load capacity at cross section a-a is equal to the load capacity at cross section b-a of the non-jointed part.
The load capacity decreases to about 215 compared to the load capacity at b. In the embodiment shown in FIG. 2, by shifting the positions of the end faces of the arrowed parts 5 from each other, the number of reinforcing cords that are cut at the cross section a-a including the abutting face between the end face of the protruding part 5 and the bottom face of the recess 6 Since there is one each, each cross section a
The load capacity at -a is kept at about 4/5 of the load capacity at non-bonded cross section bb, but as described above, the plurality of protrusions 5... and recesses 6. Since the positions of φ... are shifted from each other, it is inevitable that the punching process, joining work, etc. become complicated.Furthermore, in this embodiment, the surface-joining ends are brought into contact with each other and are bonded by fusion etc. Since the belt is joined, there is a risk that sink marks may occur due to lack of material at the joint, resulting in a decrease in the strength of the belt.

In view of the problems in the embodiments according to the prior art described above, the present invention provides recesses in each of the surface joint ends so as to face each other, and when the surface joint ends are abutted against each other, the recesses are formed. Insert a separately prepared connection chip that is roughly rectangular into the four-bar-shaped cavity, and apply appropriate pressure and pressure.
By using a heating means to fuse the surface joint end and the connecting tip with each other, the reduction in load capacity due to the cutting of the reinforcing cord at the joint can be avoided by embedding the reinforcing cord in the connecting tip in the belt to be connected. This is intended to be prevented by making the reinforcement cord stronger than the reinforcing cord. By setting the thickness of the connection tip to be slightly thicker than that of the belt to be welded, the excess thickness of the connection tip flows into each abutment part during pressurization and heating, reducing the load caused by the sink phenomenon. This has the effect of preventing a decline in performance. The formation of protrusions and recesses at the end of the surface joint and the cutting of the connecting tip prior to joining must be done so as not to cause any deviation in the pitch of the teeth after joining, or the arrangement of the teeth must be equivalent to that of the teeth. Accurate machining is achieved by preparing a machining jig consisting of a die with a groove and a punch with a contour corresponding to the recess.

Embodiments of the belt joining method according to the present invention will be described below based on the drawings. In the embodiment of FIGS. 3 and 4, mutually opposite projections 5 are provided at the surface joint ends 3.4.
and four portions 6 are provided, while having a wall thickness T greater than N compared to the wall thickness t of the belt 1 to be joined, so that when the surface joint end portions 3.4 are abutted, the belt is formed by both the recesses 6.6. A generally rectangular connecting chip 1 having a contour corresponding to the empty space 9
0 is prepared, the connecting chip 10 is inserted into the cavity 9, and the surface joining end portion 3.4 and the connecting chip 10 are pressure-fused to each other using a pressurizing/heating means described later to perform surface joining. end 3,
4 are joined together.

In the embodiment of FIG. 3, the cross section a including the bottom surface of the recess 6 is
Since the number of 70 reinforcement cords that are not cut at -a is 2/3 of the total number of reinforcement cords, the load capacity at this cross section a -a is about 2/3 of the load capacity at cross section bb of the non-joined part. The load capacity in the cross section C-C including the surface where the surface joint ends 3.4 are abutted is determined by the strength of the reinforcing cord embedded in the connecting chip 10. By setting the strength of the reinforcing cord buried in the surface of the reinforcing cord to be the same as the strength of the reinforcing cord in the section a-a, the face-to-face joint end 3.
The load capacity at cross section c-c including the abutment surface of No. 4 is equal to cross section a
The load capacity is maintained at approximately the same level as in -a, and a significant decrease in load capacity due to bonding is prevented.

In the other embodiment shown in FIG. 5, the number of 70 reinforcing cords cut in the cross section including the bottom surface of the recess 6 is 315 of the total number of reinforcing cords, so the strength of the reinforcing cords buried in the connection chip 10 is reduced. By setting the strength of the reinforcing cord at the joint to about 3/5, the load capacity at the joint can be maintained at about 315% compared to the load capacity at the non-joint part.

FIG. 6 shows an embodiment of the pressurizing/heating jig used for joining belts according to the present invention. It is equipped with a blade, a groove 16 having the same shape as the belt to be joined, and a heating means using electric heating. a built-in main body 15; a cover 17 connected to the main body 15 by a hinge; and the main body 15 and the cover 17.
It has a bolt 18 for tightening the belt, a thermostat 19 for controlling the heating temperature, and a timer 20 for controlling the heating time, and as shown in FIG. cover 1
7 is placed over the joint, and heated with electric heat while being pressed with a bolt 18 to fuse the joint.

As described above, the method for joining belts according to the present invention includes providing a protrusion and a recess that face each other at the fixed end of the belt to be joined, and inserting a separately prepared connection tip into the shape-shaped cavity formed by both recesses. Because the structure is such that the solid joint end and the connecting chip are inserted and fused to each other by means of pressure and heating, the cross-sectional size of the connecting chip and the strength of the reinforcing cord embedded in the connecting chip are By setting appropriately, it is possible to minimize the decrease in load capacity due to joint pressure, and it is also possible to keep the thickness of the connecting tip to be relatively thick compared to the thickness of the belt to be joined. In addition, it is also possible to prevent a decrease in the load capacity due to the sinking phenomenon of the abutment portion during fusion bonding.

[Brief explanation of the drawing]

1 and 2 are plan views showing an example of a belt joining method according to the prior art, FIG. 3 is a plan view showing an example of a belt joining method according to the present invention, and FIG. 4 is a plan view showing an example of a belt joining method according to the present invention. 5 is a plan view showing another embodiment of the present invention, and FIG. 6 is a sectional view of a joining jig used for joining belts according to the present invention. FIG. 7 is a perspective view showing the embodiment, and FIG. 7 is a perspective view showing the state of belt joining using the joining jig shown in FIG. 6. 1... Belt to be joined, 3... One joining end,
4 fist...other joint end, 5... protrusion, 6...
... recess, 7 ... reinforcement cord, 9 ... void,
IO fist... Connection chip, 15... Main body, 16
...Φ groove, 17...cover, 18--bolt, 19--thermostat, 20...
timer. Figure 1 Figure 2 Figure 3 Figure 70) Figure 7 Procedural Amendment (Voluntary) 1981-Mon. 29 [] Commissioner of the Japan Patent Office Shima 1) Indication of Spring Fallen 1 Case 1982 Patent Application No. 97171, Invention Name Belt joining method 3 Correcting person's life [Hayashi? IN Patent Applicant (ISS Group Number 105 Address 1-12-15 Shiba Daimon, Minato-ku, Tokyo)
Name (438) G Hon Oil Seal Kogyo Co., Ltd. + 1) Column for detailed explanation of the invention in the specification 12) Brief explanation of the drawings in the specification (3) Contents of amendment to drawing 5 + 11 Section 2 of the specification a The method described in lines 6 and 7 of the page, ``Is it a method of cutting to the required length and abutting both ends and fusing them to make it endless?'' The method is to fuse the parts to each other and stroke them endlessly. (2) One example described on page 3, line 20 of Akira @B Buttocks.”
? , amended to "this joining method". (3) "Embodiment based on prior art" written in page 4, line 5 of the memorandum is corrected to "joining method based on prior art." (4) [
1 and 2 are plan views showing an example of a belt joining method according to the prior art. Plan view, ] is corrected. (5) Figures 3, 4, 5, and 7 of the drawings are corrected according to the attached drawings. 7. List of attached documents (1) Drawings 1 or more copies Figure 3 Figure 4

Claims (1)

[Claims] 1. Reinforcement cord (power-embedded pel to be joined) (1
A protrusion (5) and a recess (6) are provided in each of the joint ends f31 (41) of 1 so as to face each other, and when the joint ends +3) (4) are abutted against each other, A connecting chip αυ having a substantially rectangular shape is inserted into the space (9) formed by both the recesses (6) and (6), and is heated by pressurizing and heating means.