JPS6165937A - Belt with teeth and its manufacturing method - Google Patents

Abstract

PURPOSE:To improve wear-proofness and strength of a belt with teeth by mixing a lubricative synthetic resin on a reinforced spread cloth layer covering a tooth face of the belt with teeth over the outer surface thereof from a joint face with the tooth face. CONSTITUTION:A spread cloth 5a made of a material such as having a low friction coefficient like a nylon is put on a surface of a tooth portion 1a of a belt with teeth having the portion 1a, and a lubricative synthetic resin 6 is mixed in the cloth. Then, wear on the tooth portion generated by sliding contact with a pulley can be prevented by the reinforced spread cloth layer 5 formed on the surface of the tooth portion. And when the belt with teeth is contacted to the pulley, the lubricative synthetic resin is oozed on the contact face of the tooth portion, and wear can be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a toothed belt in which the tooth surfaces of the tooth portions are covered with a reinforcing canvas layer, and a method for manufacturing the same.

(Prior art) Conventional toothed belts, especially standard trapezoidal toothed belts, have insufficient tooth strength compared to the belt strength. In most cases, the teeth are not damaged, and the tensile member, that is, the belt itself, is rarely damaged, which is a cause of shortening the service life.

In view of this point, as a means to improve the strength of the tooth part,
To improve the shear fatigue strength δ by completely improving the stiffness of the mountain part, ■
Improving the wear resistance of the teeth and reducing the number of threads in the ridges to improve strength; ■Improving the shape of the ridges in the ridges to distribute and even out stress to prevent stress concentration and improve fatigue resistance. Possible things to do.

Regarding (■) above, the teeth are made of an elastic material, so even if the shape of the peak is specified, the shape will not be affected by the load (
This changes accordingly, making it difficult to obtain sufficient improvement effects.

Therefore, we focused on the above point (■) and developed a technology to improve the resistance of the tooth part.
-11//71. , a toothed belt using wear-resistant canvas having self-lubricating properties, t9,
A toothed belt using a canvas is described in which the woven grooves on the tooth side surface of the canvas are filled with a rubber mixture to which a lubricant such as graphite is added.

This threaded belt is made of graphite, etc., which is rubbed into the woven grooves of the canvas together with rubber when the canvas is damaged by contact with the pulley while running. The A M agent is supplied to the welding surface, and by its action to keep the friction coefficient of the contact surface at a low level, it completely prevents wear of the canvas. Although it has a structure that improves the wear resistance of the iB part in (■), it does not have the effect of improving the rigidity of the tooth part (■), and in particular, when used as a lubricant, the high temperature Since the stability is lowered, the lubricating effect is slightly lowered in a high temperature atmosphere (0° C. or higher), and there is a problem in that the effect of improving wear resistance cannot be sufficiently obtained. Furthermore, since the canvas is required to have a large number of woven grooves, the weaving structure is limited and the types of canvas that can be used are limited.

Furthermore, since the rubber glue containing a lubricant is rubbed into the canvas in advance, the elongation of the canvas is suppressed, making it unsuitable for molding by press-fitting.

Therefore, in order to improve the wear resistance of the tooth part and the rigidity of the tooth part to improve the strength of the tooth part and improve the durability of the belt, the applicant covered one side of the tooth part. Abrasion-resistant reinforcing materials with high hardness or high elasticity are mixed on the inside and outside surfaces of the sail garden of the reinforced canvas layer, and additional adhesive rubber mixed with reinforcing materials is placed on the inner surface of the reinforced canvas layer. Developed a toothed bell) and filed an application earlier (Japanese Patent Laid-Open No. 1983-
656su No. 9).

However, although the above technology is sufficiently effective in improving the durability of the belt, wear-resistant reinforcing materials are generally expensive and the number of man-hours required to manufacture them increases, so it is a long-term goal that increases costs. be.

Additionally, Japanese Patent Publication No. 73 discloses abrasion-resistant fabrics arranged alternately and closely fitted along the tooth and land portions to form a surface cover for these portions.
It is described that an elastomeric impermeable material is entirely attached to the outer surface of the elastomer, and that the elastomeric impermeable material has a coefficient of friction that is significantly smaller than the coefficient of friction of the elastomer used.

However, in the above technology, the elastomer impregnation layer is 1
However, this impermeable layer is intended to prevent the urethane, which has a coefficient of friction of 1, from protruding onto the outer surface of the canvas, and disappears at the beginning of running, reducing the effectiveness of the shaft support. I can't expect that. Moreover, since the elastomer impermeable layer is pre-adhered to the canvas, the canvas does not stretch, and it is necessary to mold the canvas one by one along the molding mold and fit the canvas along the mold. , there is a problem that it is inefficient and becomes a cost amplifier.

(Objective of the Invention) In view of the above points, the present invention aims to improve the wear resistance of the tooth surface, improve strength by reducing tooth wear, and further improve the rigidity of the tooth part, thereby increasing durability. It is an object of the present invention to provide a toothed belt and a method for manufacturing the same which have significantly improved characteristics.

(Disclosure of the Invention) The toothed belt of the present invention relates to an improvement of the toothed belt in which the protruding surface of the tooth portion is broken at the 11j strong canvas layer, and the reinforcing canvas layer extends outward from the joint surface with the protruding surface. It is characterized by containing a lubricating synthetic resin over the entire surface.

The above-mentioned slippery synthetic resin is preferably a thermoplastic resin having a melting point of about 7 gθ0C or less. In addition, the m of thermoplastic resin μm - ≠, molypide/, graphite, metal powder, fluorine fiber, carbon fiber, aramid fiber, etc.
It is desirable that lubricant be mixed in an amount of 10 to 50% by weight.

one! The manufacturing method of the present invention relates to a method for manufacturing a toothed belt in which the tooth surfaces of the tooth portions are covered with a reinforcing canvas layer, and is made by using a mold in which grooves in the axial direction are formed at a pitch on the outer peripheral surface. ,
A 5M treated area fabric formed in accordance with the circumference of the mold is attached, and at least one layer of lubricating synthetic resin sorting and adhesive treatment is decorated on the outside of the fabric. and uncured rubber) are wound in the order of k, and then the sleeve is completely fitted onto the outside and pressure vulcanized.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In the toothed belt 1 having the standard trapezoidal chevron-shaped tooth portion 1a shown in FIG. 1, 2 is i4! The Iwouke is a tensile material that has a high elastic modulus, such as glass fiber or steel wire. Reference numerals 3 and 4 denote an upper rubber layer and a toothed rubber layer, which are made of an elastic material such as chloroprene rubber, which are attached to the anti-cavity bowl 21 and form a belt shape. 5 is (11 strong canvas Jω
It is formed using a canvas material with a low coefficient of friction such as nylon that protects the tooth surface, and has a lubricating synthetic 1 inside.
-Contains all 6 fats.

FIG. 2 shows a state in which the lubricating synthetic resin 6 is present in the reinforcing canvas layer 5 in contact with the tooth coam Δ4, and the reinforcing canvas layer 5 is located outside from the joint surface 5b with the tooth surface. One lubricating synthetic sealant 6 is uniformly contained over the surface 5C.

The lubricating synthetic resin 6 is a thermoplastic material having a melting point of about /gθ0C or less, such as polyethylene (0 point: 737°C), polypropylene (melting point: 76°C), copolymerized or modified nylon, etc. They will be adopted as appropriate. Furthermore, in order to improve lubricity, lubricants such as graphite, molybdenum, carbon, metal powder, fluorine fiber, carbon fiber, aramid, and ultra-hard gold kA are added to the thermoplastic synthetic resin in the form of short fibers or particles. When using a short wall filament, the filament diameter should be ~10μ and the aspect ratio (length/diameter) should be 3.
When ~/S is used in bulk or particulate form, it is desirable that the particle size is j ~ 5θμ, but regardless of the shape, the mixing ratio in the thermoplastic synthetic resin is , it is necessary to carry out the weight ratio within the range of 10 to j0ch.

The lubricating synthetic resin 6 has adhesive properties to the elastic material of the toothed rubber layer 4 and the canvas of the reinforcing canvas WJ5, and is present between the toothed rubber layer 4 and the reinforcing canvas layer 5. However, in order to improve the adhesion with them, for example, Regilson formalin condensation low polymer resin or block isocyanate (for example Hylen) is added to the lubricating synthetic resin.
e 'h/fp, DuPont 11) or REL on the surface of the lubricating synthetic tJ lubricant before belt forming.
An adhesive or incyanate adhesive may be applied.

Note that the i1J synthetic resin 6 present on the surface of the reinforcing canvas layer 5 completely covers the entire surface or partially covers the entire surface, but from the viewpoint of improving abrasion resistance, It is advisable to cover it.

Next, a method for manufacturing the toothed belt will be explained.

First, a canvas that stretches in one direction (unbonded woven fabric)
Tooth-shaped recesses (grooves) in the @ line direction at a pitch on the t-1 outer circumferential surface
Either finish it into a cylindrical shape corresponding to the same length of the mold and insert it outside the mold, or wrap the canvas around the outer circumferential surface of the mold and fix the ends of the canvas with adhesive or the like. .

Then, on top of that, for example, a thin polyethylene sheet (7-layer synthetic resin sheet) than the above-mentioned canvas, at least /
Wrap the layers and heat seal the ends.

On the above sheet, glass fiber, t”A 1.;j
A tensile member 2 made of aromatic polyamide or the like which has been subjected to a special adhesive layer treatment is wound in a spiral shape by wrapping 7 to 2 pieces.

The pitch of the winding is approximately /, /~, θ times the diameter of the cord.

A total of 7 layers or 2 layers of unvulcanized rubber sheets, which will form the toothed rubber layer 4 and the upper rubber layer 3, are wrapped around the tensile member 2, and a force 1 sleeve is removed from the outside. The product is bottomed, subjected to a predetermined t1 treatment using a well-known vulcanizer, pulled out from the mold, and then cut into a belt shape to obtain the desired toothed belt 1.

In addition, in the above-mentioned vulcanization process, Fig. 3 (a) to (b)
It is thought that the situation shown in is occurring. That is, the third
As shown in Figure (a), a mold 1 having tooth-shaped recesses 11a'
When the belt implantation material is wrapped around the outer circumferential surface of rubber sheet 1 and vulcanized under pressure, the unvulcanized rubber sheet 12 is softened and pushed toward the mold 11 by pressure, forming a spiral. shaped tensile body 2
The IFL slippery synthetic resin sheet 13 and the canvas 14, which have already been softened, are moved through the gap in the tooth-shaped recess 11 of the mold 11.
(See Fig. 3(b)).

As the process progresses further, the canvas 14 takes on a shape that follows the tooth-shaped recess 11a (see Figure 3 (C)), and the lubricating synthetic resin notebook 13 softens and becomes fluid at the vulcanization temperature (/gθ~/6θQC). Since it is in a state of

- At that time, the canvas 14 is stretched by 30 to 5θ with respect to its original state, so it not only fills the above-mentioned weave, but also
In some cases, the outer surface of 4 is also coated.

In this way, vulcanization of the rubber of the unvulcanized rubber sheet 12 begins after the formation of the tooth shape is completed. Therefore, as a lubricating synthetic resin, it softens at the vulcanization temperature and forms the texture of the canvas under the vulcanization pressure. As mentioned above, it is desirable to use a thermoplastic resin having a melting point of /gθ0C or less.

Depending on the vulcanization conditions and the amount of lubricating synthetic resin used, the toothed rubber K (
! 4 t- When the constituent rubber flows in, as shown in Figure 7 (C), if the lubricating synthetic resin 6 is present even inward from the inner surface of the canvas layer 5, the flow will be as shown in Figure (C). When the lubricating synthetic resin 6 covers the outer surface of the canvas layer 5 as shown in FIG. When the outer surface of the canvas layer 5 is coated with a lubricating synthetic resin 6, as shown in FIG. There are cases where it is covered, but in either case, the same effect is achieved.

With the above configuration, basically, the reinforcing canvas J-5 that runs along the surface of the teeth of the toothed belt will prevent the peaks from being worn out due to sliding contact with the pulleys or interference during meshing. In particular, the use of nylon 16 as the canvas material has some lubrication effect. In addition, since the reinforcing canvas layer 5 contains the lubricating synthetic resin 6, when the toothed belt comes into contact with the pulleys and undergoes a certain degree of wear and tear, the lubricating synthetic resin 6 is added to the contact surface of the teeth. The resin 6 comes out and its wear is completely suppressed.

In addition, the stiffness of the teeth as a composite material is improved by the reinforced canvas layer 5, and when the peaks mesh with the pulley, the deformation due to bending and shearing received from the pulley becomes smaller, and the shear fatigue strength g( Durability has been improved.

Next, test results of the effect of the present invention where h=g will be explained.

Test/ The belt with the belt of the present invention and the toothed belt of the conventional type were Peltro type, pitch: ZA type, 9. S23; mm belt width, (Jin: /9.0mm,
? ! ; Mountain man ambient temperature 2 and θOC Followed shaft load power Knee 2・jps Drive shaft rotation a: 6.0001m Belt initial tension
Figure S shows the comparative results of a tooth canvas wear test carried out under test conditions of: , 2jkgf. In addition, the conventional type is one in which the reinforcing canvas layer does not contain a lubricating synthetic resin, the inventive type 1 is a type in which a polyethylene sheet is used as the lubricating synthetic resin, and the inventive type 2 is a type in which a lubricating synthetic resin is used as the lubricating synthetic resin. It uses polyethylene mixed with 20% by weight of graphite. Also, what is sail wear survival rate?
The ratio of the tooth surface canvas thickness after the belt runs to the tooth surface canvas thickness before the belt travel is shown, and the canvas thickness is measured using an industrial microscope.

As is clear from FIG. 5, the belt with 1 and 20 threads of the present invention has a wear resistance of 1-20 compared to the conventional toothed belt.
This is a 6x improvement.

In addition, in order to further improve the adhesion of the slippery synthetic resin, for example, a sheet may be used to mix 2% resorgino formalin resin into polyethylene resin. It has been confirmed that the adhesive strength of the manufactured belt with the belt is improved by approximately 2θ with almost no effect on the 'rx abrasion residual rate.

Test 2 Figure 6 shows the comparative results of a load durability test of a toothed belt with varying load power for the mountain shear fatigue strength under both running conditions similar to the canvas abrasion test described above. ing. Note that the durability life is the time required for the white part of the toothed belt to break due to shearing.

As is clear from Fig. 6, the toothed belt of the present invention type (the present invention type 1 in the test) has a durability life that is 5 to -6θ times longer than that of the conventional @ type belt. There is.

In the above embodiments, a U-shaped belt with a standard trapezoidal tooth profile has been described, but it goes without saying that the present invention can also be applied to a toothed belt with a circular arc tooth profile.

(Effects of the Invention) According to the toothed belt of the present invention, the reinforcing canvas layer has a lubricating composition (
Since it contains all the fat, the wear resistance of the mountain surface is improved,
The strength is improved by reducing the wear of the teeth, and the rigidity of the ridges is also improved, which greatly improves overall durability.

By the way, according to the manufacturing method of the present invention, it is possible to easily manufacture a chamfered belt that exhibits the above-mentioned effects.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional view of a toothed belt, FIG. 1 is an enlarged view of section A in FIG. 1, and FIG.
a) to (b) are explanatory diagrams of the tooth forming state of the toothed belt, No. 9
Figures -) to -) are cross-sectional views showing the condition of the gamma-slip synthetic resin in the reinforced canvas layer, Figure 5 is a graph showing the results of the toothed canvas wear test, and Figure 6 is the shear fatigue strength of the peak. This is a graph showing the results. 1... Belt with surface, 1a... Teeth, 5...
... Reinforced canvas layer, 6 ... Lubricating synthetic resin, 11
...Mold, 11a...Tooth mold recess, 12
・Unvulcanized rubber sheet, 13... Lubricating synthetic resin sheet, 14... Hoa No. 30
4121b Figure 5 Run fr yesterday (1-1)

Claims (4)

[Claims] (1) A toothed belt in which the tooth surfaces of the tooth portions are covered with a reinforcing canvas layer, characterized in that the reinforcing canvas layer contains a lubricating synthetic resin from the joint surface with the tooth surface to the outer surface. Toothed belt. (2) The toothed belt according to claim 1, wherein the lubricating synthetic resin is a thermoplastic resin having a melting point of about 180° C. or less. (3) The lubricating synthetic resin is a thermoplastic resin mixed with 10 to 50% by weight of a lubricant made of molybdenum, graphite, metal powder, fluorine fiber, carbon fiber, aramid fiber, etc. A toothed belt according to scope 2. (4) A non-bonded woven fabric formed to correspond to the circumference of the mold is attached to a mold in which axial grooves are formed at a constant pitch on the outer circumferential surface, and at least one layer of lubrication is applied to the outside of the mold. 1. A method for manufacturing a toothed belt, which comprises sequentially wrapping a synthetic resin sheet, an adhesive-treated tensile material, and an unvulcanized rubber sheet, and then fitting a sleeve around the belt and vulcanizing it under pressure.