JPS61136038A - V-belt - Google Patents

Abstract

PURPOSE:To prevent the terminal end of a wrapped outer skin canvas from peeling off, by positioning one belt-widthwise side edge of the outer skin canvas outside of the other side edge thereof over the entire circumference of a belt. CONSTITUTION:In a wrapped V-belt 1 a belt core 2 is covered around the entire periphery of the belt core 2 with an outer skin canvas 3. One belt-widthwise side edge 3a of the outer skin canvas 3 is positioned outside of the other side edge 3b over the entire circumference of the belt. Accordingly, when the unvulcarnized belt core 8 onto which the outer skin canvas 3 wrapped is set in a vulcanizing dies 9, if the belt core 8 is disposed therein such that the one side edge 3a positioned on the outside in accordance with the wrapping direction B of the outer skin canvas 3 is retained, it may be set in the dies 9 without the outer skin canvas 3 peeling off.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a V-belt formed by wrapping a belt core with an outer canvas, and particularly relates to the structure of the wrapping of the outer canvas. .

(Prior Art) Conventionally, so-called lap V-belts in which the periphery of the belt core d is covered with an outer covering canvas are shown in FIGS. 7 to 10.
As shown in the figure, at the joint part of the outer canvas canvas, the corner C1 corresponding to the outer corner d1 of the winding start end d of the winding end C of the core outer canvas canvas is turned inward. , the corner c2 corresponding to the inner corner d2 of the winding start end d is on the outer side, and both corner parts C1+02 are exposed on the outer surface.

However, if the outer covering canvas is wrapped with such a structure, even if a force is applied from the direction of the belt widthwise inclination, the force will be applied to the corner C1 of the winding end C of the outer covering canvas. Or, since it acts to separate one side of C2, when the outer canvas is wrapped around the unvulcanized belt core and then installed in a ring-shaped vulcanization mold, a force in the belt width direction is applied. However, depending on the direction, the corner c1 or C2 of the winding end C of the outer canvas sheet may peel off and be vulcanized in that state, resulting in a defective belt.

By the way, conventionally, in order to prevent the above-mentioned outer covering canvas from peeling off at the end of the winding when it is attached to the vulcanization mold, i.
) For example, by having the worker press strongly with his/her hand after every 7th roll, the adhesion of the unvulcanized end of the outer canvas can be improved. 1) Also, the length of the unvulcanized belt attached to it should be slightly longer to make it easier to attach.1ii) After attachment to the vulcanization mold, use a knife, spatula, etc. to remove peeling, wrinkles, etc. at the joint part. Techniques such as correcting the parts where this occurred were adopted. However, method i) requires more man-hours due to manual work, method ii) increases elongation of the finished belt during operation, and method ii).
) method requires a lot of man-hours and has disadvantages such as the possibility of overlooking areas where peeling or the like occurs, so it cannot be said to be sufficient.

(Object of the Invention) An object of the present invention is to provide a V-belt that can prevent the occurrence of peeling at the winding end of the outer canvas when it is attached to a vulcanization mold. be.

(Disclosure of the Invention) The present invention relates to an improvement of a wrapped V-belt in which the periphery of a belt core is covered with an outer covering canvas.

The present invention is characterized in that one side edge of the outer covering canvas in the belt width direction is located on the outside of the other side edge over the entire circumference of the belt. That is, by wrapping the outer canvas around the belt core in one direction over the entire circumference of the belt, and attaching it to the vulcanization mold according to the direction, the winding of the outer canvas can be done. 0 (Example) Examples of the present invention will be described below with reference to the drawings.

In Figures 1 to 7, 1 is a lap V-belt;
The periphery of the belt core body 2 is covered with an outer covering canvas 3.

As is well known, the belt core 2 has a substantially trapezoidal cross section and consists of a bottom rubber layer 4 which is cushion rubber, and a tensile layer 5 stacked on top of the bottom rubber layer 4. The tensile material layer 5 is made up of a cord (tensile material) embedded in adhesive rubber.

The outer covering canvas 6 is formed by sequentially overlapping the side edges of unit bias cloth pieces made by cutting a rubberized plain weave canvas into a bias shape, and connecting them by the adhesion of the rubber, and surrounds the belt core body 2. One side edge 3 in the belt width direction
a is located on the outside of the other side edge 3b over the entire circumference of the belt. ○However, at the joint part A, the end of the winding end B of the outer covering canvas 3 is located inside of the winding start end 7. Corner 6a of the other side edge 6b corresponding to corner 7a of the other side edge 6b
is located on the inside, and a corner 6b of the one side edge 3a corresponding to the corner 7b of the one side edge 3a that is the outside of the winding start end 7 is exposed on the outer surface and located on the outside. That is, the outer covering canvas 3 is wrapped around the belt core 2 in the same direction B over the entire circumference of the belt.

Therefore, when attaching the unvulcanized belt core 8 wrapped with the outer covering canvas 3 to the heating mold 9, the outer covering canvas B is wrapped in the direction B, as shown in FIG. In other words, by pressing down on one side edge 3a located on the outside, the outer covering canvas 3 can be installed without peeling, and the occurrence of defective products can be prevented.

Next, a test comparing the belt performance of the present invention type and the conventional type regarding the A-type 3S Lapto V-belt will be explained.

i) Test method As shown in Figure 4, the drive pulley 11 (diameter 7θrn-
, /gθθrμs) and the driven pulley 12 (diameter 7θmm
), the test belt 13 is wound between the driven pulley 12
Load W-='1 in the direction away from the drive pulley 11
0 kg was added, and the time until cracks appeared in the joint portion of the test belt 13 was measured.

i) Test results The time ratio until crack occurrence is as follows.

(Conventional type) = (Invention type) = To θ: (2, θ ~ 3. θ)
This shows that the belt according to the invention has a longer service life and is more durable than the conventional belt.

↓ If the corners of the belt are wound alternately and a force is applied in the peeling direction from side to side in the width direction of the belt while the belt is running, stress will be concentrated in that part and cracks will occur early. In the case of the shape, the outer canvas is wrapped in one direction all around the belt, so the corners of the joints are not staggered at 7 as in the conventional shape, which reduces the degree of stress concentration. It is assumed that this is because it is small.

In the above embodiment, each corner 6a, 6b of the outer covering canvas 6.

Although the overlapping portion of 7a and 7b is located on the bottom surface of the belt (see FIGS. 3 to 7), it is also possible to configure the overlapping portion to be located on the back surface of the belt.

(Effects of the Invention) Since the present invention is configured as described above, when the present invention is installed in the vulcanization mold, if it is installed so as to press the side edges located on the outside, the end of the winding of the outer covering canvas can be achieved. There is no risk of the edges peeling off, and quality can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of the V-belt of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, FIG. 3 is a sectional view taken along the line ■[-m in FIG. 5 is a diagram showing the V-belt of the present invention installed in a vulcanization mold, FIG. 4 is an explanatory diagram of the test system, and FIG. 7 is a schematic perspective view of the conventional V-belt. The second figure is a cross-sectional view taken along the line ■-■ in FIG. 7, FIG. 9 is a cross-sectional view taken along the line IX--IX in FIG. 7, and FIG. 1θ is a cross-sectional view taken along the line X-X in FIG. 1... Wrap V-belt, 2... Belt core, 6... Outer canvas, 3α-49"1
31) Loquai 91] Edge Figure 1 Figure 6 Figure 7 Figure 8 Figure 10 r

Claims (1)

[Claims] (1) V formed by wrapping the belt core with an outer covering canvas
A V-belt, characterized in that one side edge of the outer covering canvas in the belt width direction is located on the outside of the other side edge over the entire circumference of the belt.