JPH0893781A - Flexible joint and manufacturing method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a flexible joint capable of exhibiting stable characteristics from the beginning of production without requiring a special leveling work for stabilizing the characteristics, and a manufacturing method thereof. Especially. [Structure] A reinforcing fiber 4 is wound a plurality of times between a pair of outer cylinder members 3, 3, and contact portions P, P of the reinforcing fiber 4 in contact with the outer cylinder members 3, 3 are corresponded by an adhesive 8 to the outer cylinder member. 3 and 3 are adhered and fixed, a urethane rubber coating film 7 is formed on the outer peripheral surfaces of the winding portions Q, Q of the reinforcing fiber 4, and silicone oil is injected into the coating film 7 for further reinforcement. The entire fiber 4 was molded with a rubber elastic body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible joint and a method for manufacturing the same, and more particularly, to a flexible joint suitable for connecting a drive shaft and a driven shaft of a power transmission system of an automobile. And a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, as a flexible joint of this type, for example, one disclosed in Japanese Utility Model Laid-Open No. 59-146623 is known.

In such a flexible joint, a cylindrical body connected to the drive shaft side and a cylindrical body connected to the driven shaft side are alternately arranged at equal intervals along the circumferential direction of those shafts. Each of the adjacent tubular bodies is wrapped with a specially processed fiber cord as a reinforcing fiber a plurality of times, and these fiber cords are covered with a rubber elastic body. . Further, the tubular body is provided with an intermediate flange, and the intermediate flange restrains the loops of the adjacent fiber cords so as to separate them from each other.
When the fiber cord and the tubular body are bonded and fixed, or when the whole is covered and molded with the rubber elastic body in the next step, the loops of the fiber cord may bite into each other or the shape of the loop may be disturbed. There is also one that is intended to prevent deterioration of the flexible joint over long-term use.

[0004]

In such a conventional example, polyamide fiber or polyester fiber having a large elongation is used as a fiber cord, and the fiber cord is made of a flexible material such as a rubber elastic body. When a flexible joint is used, if a tensile force acts between two adjacent tubular bodies, the fiber cords wound a plurality of times overwhelm the stress relatively evenly. The strength proportional to the number of turns is developed, and there are few strength problems.

However, since the winding portion of the fiber cord wound between two adjacent tubular bodies is integrally bound by the vulcanized rubber elastic body to have a square cross section, for example, , When a tensile force acts between two adjacent tubular bodies under the torsional stress of the flexible joint, or a bending stress acts under the load in the direction parallel to the driving shaft and the driven shaft. At the same time, the winding portion of the fiber cord exhibits high rigidity, and when stress is repeated, hysteresis occurs due to the property of the rubber elastic body, and the rigidity value changes. Therefore, in general, before using it,
Repeatedly apply alternating stress until the stiffness value stabilizes,
We are doing so-called “break-in” work.

The present applicant has previously proposed a flexible joint in which the winding portion of the fiber cord is impregnated with oil (Japanese Patent Application No. 5-86099). In such a flexible joint, the winding portion is impregnated with oil before the fiber cord is covered with the elastic rubber. However, if the fiber cord is then covered with a liquid rubber elastic body such as urethane rubber by vacuum forming, for example, the liquid rubber elastic body penetrates between the fiber cords of the winding section and it hardens. When doing so, the winding unit may be bound together. When the winding units are integrally bound in this way, the "leveling" operation similar to the conventional one described above is still required.

An object of the present invention is to provide a flexible joint capable of exhibiting stable properties from the beginning of production without requiring a special leveling work for stabilizing the properties, and a method for producing the same. Especially.

[0008]

In the flexible joint according to claim 1 of the present invention, a reinforcing fiber is wound a plurality of times between a pair of cylindrical bodies provided on the drive shaft side and the driven shaft side. In a flexible joint in which the link element is covered with a rubber elastic body, the tubular body and the portion of the reinforcing fiber in contact with the tubular body are adhesively fixed, and are positioned between the pair of tubular bodies. The reinforcing fiber winding portion is provided with a bond preventing material for preventing the reinforcing fibers from being bonded to each other by the rubber elastic body.

The flexible joint according to claim 1 of the present invention comprises:
The flexible joint according to claim 1, wherein the coupling preventing member is
A coating film for coating the outer peripheral surface of the winding portion of the reinforcing fiber, and a lubricating liquid impregnated in the winding portion inside the coating film.

The flexible joint according to claim 3 of the present invention comprises:
The flexible joint according to claim 1, wherein the coupling preventing member is a covering material that covers the reinforcing fibers of the winding portion so as to be relatively displaceable.

The flexible joint according to claim 4 of the present invention is
The flexible joint according to claim 1, wherein the coupling preventing member is a covering material that covers the reinforcing fibers of the winding portion so as to be relatively displaceable, and a covering film that covers the outer peripheral surface of the winding portion. Is characterized by.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a flexible joint, wherein a link is formed by winding a reinforcing fiber a plurality of times between a pair of cylindrical bodies provided on a drive shaft side and a driven shaft side. A method for manufacturing a flexible joint in which an element is covered with a rubber elastic body, wherein the pair of tubular bodies and the pair of tubular bodies are wound around each other when the link element is manufactured. After bonding and fixing the portion of the reinforcing fiber in contact with the tubular body, after forming a coating film on the outer peripheral surface of the winding portion of the reinforcing fiber located between the pair of tubular bodies, A lubricating liquid is impregnated in the winding portion inside the coating film.

A method for manufacturing a flexible joint according to a sixth aspect of the present invention is a link in which a reinforcing fiber is wound a plurality of times between a pair of cylindrical bodies provided on the drive shaft side and the driven shaft side. A method for manufacturing a flexible joint in which an element is covered with a rubber elastic body, wherein the pair of tubular bodies and the pair of tubular bodies are wound around each other when the link element is manufactured. After adhesively fixing the portion of the reinforcing fiber in contact with the tubular body, after impregnating the wound portion of the reinforcing fiber located between the tubular bodies of the pair with the coating liquid material, the tubular shape of the pair The coating liquid material is cured while changing the distance between the bodies.

[0014]

In the flexible joint according to the first aspect of the present invention, the reinforcing fiber is provided with a binding preventing material in the winding portion, and the reinforcing fibers are coupled to each other by the rubber elastic body covering the link element. To prevent.

The flexible joint according to claim 2 of the present invention comprises:
By covering the outer peripheral surface of the winding portion of the reinforcing fiber with a coating film and impregnating the inside thereof with a lubricating liquid, abrasion and damage due to friction between the reinforcing fibers in the winding portion are also prevented.

The flexible joint according to claim 3 of the present invention comprises:
The covering material that covers the reinforcing fibers in the winding portion such that they can be displaced relative to each other prevents the reinforcing fibers in the winding portion from being integrally bound.

A flexible joint according to claim 4 of the present invention comprises:
The reinforcing fibers in the winding section are covered with a covering material so as to be relatively displaceable, and the outer peripheral surface of the winding section is further covered with a coating film, whereby the reinforcing fibers in the winding section are integrally bound. This is more reliably prevented, and at the same time, abrasion and damage due to rubbing of the reinforcing fibers in the winding portion are prevented.

According to a fifth aspect of the present invention, in the method for manufacturing a flexible joint, a coating film is formed on the outer peripheral surface of the winding portion of the reinforcing fiber, and a lubricating liquid is impregnated inside the coating film.
Preventing the reinforcing fibers of the winding part from being integrally bound by the rubber elastic body, exhibiting stable characteristics from the beginning,
In addition, a flexible joint that is free from wear and damage due to friction between reinforcing fibers in the winding portion is manufactured.

In the method for manufacturing a flexible joint according to claim 6 of the present invention, the winding portion of the reinforcing fiber is impregnated while changing the distance between the pair of tubular bodies around which the reinforcing fiber is wound. By hardening the coated molten material, the reinforcing fibers of the winding portion are relatively displaceably covered, and the reinforcing fibers of the winding portion are prevented from being integrally bound by the rubber elastic body.

[0020]

Embodiments of the present invention will be specifically described below with reference to the drawings.

(Embodiment 1) FIG. 1 shows an example of the construction of a flexible joint manufactured according to the present invention as viewed from the axial direction. In FIG. 1, 1 is rotationally driven around an axis indicated by a point O. A total of three first inner cylinder members respectively connected to circumferentially trisecting positions on the drive shaft (not shown) side, and 2
Is a total of three second inner cylinder members connected to a circumferentially trisecting position on the side of a driven shaft (not shown) that can rotate coaxially with the driving shaft. The three first inner cylinder members 1 and the second inner cylinder members 2 are alternately arranged at equal intervals with a center angle of 60 degrees about the point O, and are adjacent to each other.
A total of six elastic links L are installed between the inner cylinder members 1 and 2.

These elastic links L are formed by the inner cylinder members 1 and 2.
As shown in FIG. 2, a reinforcing fiber 4 such as a glass fiber is wound a plurality of times between the outer cylindrical members 3 and 3 as a pair of cylindrical members that are press-fitted to the above so as to be layered. In the reinforcing fiber 4, only the reinforcing fiber bundle 4A of the contact portion P that comes into contact with the outer tubular members 3 and 3 is bonded and fixed with a curing resin such as an epoxy resin as the adhesive material 8. And the contact portion P
The low-viscosity silicone oil 6 is impregnated into the reinforcing fiber bundles 4B of the other winding parts Q. In FIG. 1, only two reinforcing fibers 4 out of the total of six elastic links L are shown, and the other four reinforcing fibers 4 are omitted.
Then, a total of six elastic links L are integrated into a plane regular hexagon as shown in FIG. 1 by press-fitting and fixing the inner cylinder members 1 and 2 adjacent to each other inside the outer cylinder members 3 and 3, respectively. Be converted. Then, after that, the entire outer side of each of the six elastic links L is covered with the rubber elastic body 5 (see FIG. 1) to form the flexible joint 10.

Next, a method of manufacturing such a flexible joint will be described in detail with reference to FIG.

In the step of producing the elastic link L, first, as shown in FIG. 3 (a), the outer cylindrical members 3 and 3 with flanges on both ends are held and fixed at a prescribed pitch, and the reinforcing fiber 4 is placed between them. The glass fiber yarn of No. 135 as shown in FIG. At this time, only the fiber bundle 4A of the contact portion P is coated with the epoxy resin (epoxy equivalent of about 190) as the adhesive 8 and the modified heterocyclic amine-based curing agent mixture. Then, after the winding of the reinforcing fiber 4 is completed, the fiber bundle 4A is heat-cured in an oven at 80 ° C. for 3 hours to bond and fix the fiber bundle 4A to the outer tubular members 3 and 3.

Next, as shown in FIG. 3 (b), liquid urethane rubber (rubber hardness after curing with a two-component urethane rubber of isocyanate prepolymer and polyol JIS
40A) is thinly applied to the surface of the winding part Q not impregnated with resin, the outer peripheral surface is covered, and then heat-cured for 2 hours in a furnace at 60 ° C. to penetrate the surface of the winding part Q. A coating film 7 for prevention is formed and covered. Next, as shown in FIG.
1 g of silicon oil (about 500 centistokes) 6 as a lubricating liquid is injected and impregnated inside the fiber bundle 4B of the winding portion Q covered with the coating film 7.

After that, the six elastic links L are combined into a plane regular hexagon, and the whole thereof is covered with urethane rubber (JIS 40A) as the rubber elastic body 5 by vacuum forming. At that time, in order to facilitate vacuum deaeration and to prevent expansion and rupture of the coating film 7 due to deaeration, a hole having a size large enough to prevent the liquid urethane rubber from entering inside when returned to normal pressure is coated. Expose to membrane 7. Then, the rubber elastic body 5 is cured at 60 ° C. for 4 hours to complete the flexible joint 10. If the coating film 7 is strong enough to withstand rupture, it is not necessary to make the above holes. Further, the flexible joint 10 is completed by individually coating the six elastic links L with urethane rubber as the rubber elastic body 5 by vacuum forming, and then combining the elastic links L into a plane regular hexagon. Good.

Here, as the sample 1 whose bending characteristics can be easily measured, one elastic link L covered with the rubber elastic body 5 was prepared. That is, for one elastic link L on which the coating film 7 is formed, the above-mentioned holes are made in the coating film 7, and then the holes are set in the whole mold, and the whole is formed by vacuum forming. Cover with urethane rubber as rubber elastic body 5 to a thickness of about 2 mm, and then coat it at 60 ° C for 4
Sample 1 was prepared by curing for time. on the other hand,
As sample 2 for comparing bending rigidity with this sample, 1
Individual elastic links L were prepared. This sample 2 has a winding section Q
The coating film 7 is not formed on the fiber bundle 4B and the silicone oil 6 is not injected into the coating film 7 inside the fiber bundle 4B.

For each of these samples 1 and 2, one outer cylinder member 3 is fixed to hold the elastic link L horizontally, and the other outer cylinder member 3 is subjected to a cantilever beam bending to apply a load from above. The test was conducted. And, as shown in Table 1 below,
After detecting the load and yield load and its deflection at the time of bending by 1 mm by the first load, and repeatedly applying the load until the yield behavior does not appear in the bending within 10 mm,
The load at a bending of 1 mm and the load at a bending of 10 mm were detected.

[0029]

[Table 1]

As is apparent from Table 1 above, the surface of the fiber bundle 4B of the winding part Q was previously coated with the coating film 7 before the whole was coated with the rubber elastic body 5 by the vacuum casting method. The sample 1 has a lower initial rigidity than the sample 2 which is not covered by the coating film 7, and the degree of change in which the load for causing a predetermined flexure is reduced is small even if the bending load is repeatedly applied. It can be seen that the characteristics are stable from the beginning of production. In addition, Sample 1 did not suffer from insufficient deaeration during vacuum casting, had no bubbles on the surface, and had a good appearance.

(Embodiment 2) In the case of this embodiment, first, as in Embodiment 1, as shown in FIG. 4A, the glass fiber yarn as the reinforcing fiber 4 is placed between the outer cylinder members 3, 3. The fiber bundle 4A is wound around and is hardened by the mixture of the epoxy resin and the curing agent applied to the fiber bundle 4A of the contact portion P, and the fiber bundle 4A is adhesively fixed to the outer tubular members 3 and 3. Then, a solution of urethane rubber (2.5 parts of methyl ethyl ketone as a solvent is added to the uncured urethane rubber of JIS JIS 40A hardness) is impregnated inside the fiber bundle 4B of the unwrapped portion Q of the resin. Then, during the drying of the solvent, the operation of holding and fixing the space between the outer cylinder members 3 and 3 at the specified pitch, and
The operation of shortening or lengthening the interval of 3 is repeated. As a result, the fiber bundle 4B is prevented from being integrally fixed and fixed, and the individual fibers are individually covered with urethane rubber. Then, it is heated at 60 ° C. for 2 hours to cure the urethane rubber and individually coat the coating film 9 (FIG. 4) on the surface of the fibers forming the fiber bundle 4B.
(See (b)) was formed. Then, six such elastic links L are combined into a plane regular hexagon, set in a mold, and vacuum-molded to form the whole with the urethane rubber (undiluted product) as the rubber elastic body 5. After coating to a thickness of about 2 mm, the rubber elastic body 5 was cured at 60 ° C. for 4 hours.

Also in this case, as the sample 3 whose bending characteristics can be easily measured, one elastic link L covered with the rubber elastic body 5 was prepared. That is, as described above, one elastic link in which the fiber bundle 4B is individually covered with urethane rubber is set in the mold, and the whole is made of urethane rubber as the rubber elastic body 5 by vacuum forming. Coat to a thickness of about 2 mm and then apply it at 60 ° C for 4
Sample 3 was prepared by curing for time. on the other hand,
One elastic link L was prepared as a sample 4 for comparing bending characteristics with this sample. This sample 4 is a fiber bundle 4A
After being impregnated with a solution of urethane rubber, both outer cylinder members 3,
The sample 3 is different from the sample 3 only in that the fiber bundle 4B is integrally focused and fixed by fixing 3 to the specified pitch.

These samples 3 and 4 were subjected to a cantilever beam bending test similar to that of Example 1 described above, and the results of comparison of their bending characteristics are shown in Table 1 above.

It can be seen that the sample 3 has a lower bending rigidity at the first time than the sample 4, and the change is small even if the test is repeated, and the characteristics are stable from the beginning of the production.

The flexible joint 10 is formed by combining six elastic links L similar to those of the sample 3 into a plane regular hexagon.
May be configured. Further, the coating solution for forming the coating film 9 as the coating material is not limited to the solution of urethane rubber at all, for example, the hardness of urethane rubber is changed, or the elastic epoxy resin is diluted with a solvent. An aqueous emulsion of a rubber elastic body such as styrene-butadiene rubber or styrene-butadiene-acrylonitrile, or an aqueous emulsion of urethane rubber can be used. The point is that it does not easily penetrate into the winding portion Q and a film-like material as the coating film 9 is formed on the surface of the fiber. As the reinforcing fiber 4, in addition to glass fiber yarn, inorganic fiber such as carbon fiber, alumina fiber, silicon carbide fiber,
Alternatively, an organic fiber, an aramid fiber or the like or a combination of these various fibers may be used. The adhesive 8 may be different in epoxy equivalent, and the curing agent may be, for example, imidazole-based or boron trifluoride-based.

(Embodiment 3) In this embodiment, an elastic epoxy resin (polyurethane having a polyether type bond as a flexible main chain) is used as the solution of the urethane rubber constituting the coating film 9 in the above-mentioned Embodiment 2. Epoxy resin containing components) 1 part: A solution of 2.5 parts of acetone was used and cured at 100 ° C. for 2 hours. The results were the same as in Example 2.

(Embodiment 4) In this embodiment, as a solution of the urethane rubber constituting the coating film 9 in the above-mentioned embodiment 2, the solid content of the polyurethane aqueous emulsion is 20%.
The coating film 9 was formed by diluting with water and dried at 120 ° C. for 2 hours to prevent the binding of the fiber bundles 4A of the winding portion Q together. Then, as in Example 1 described above, liquid urethane rubber having a rubber hardness of 30A is applied to the fiber bundle 4B of the winding portion Q and cured at 60 ° C. for 2 hours to form the coating film 7 (see FIG. 3). did. After that, further hardness 30
The urethane rubber of A is coated with a thickness of 2 mm, and it is 60 ° C.
And cured for 4 hours to obtain a rubber elastic body 5.

One elastic link L having the above structure was used as sample 5. Further, as Sample 6 to be compared with it, when dried at 120 ° C. for 2 hours as in Sample 5,
The urethane rubber is used to integrally bind the fiber bundle 4A of the winding portion Q, and the urethane rubber having a hardness of 30A is 2 mm.
The elastic link L was prepared as a rubber elastic body 5 by coating it with the thickness of 4 and curing it at 60 ° C. for 4 hours. Then, the results of carrying out the same test as the above-mentioned samples on these samples 5 and 6 are shown in the above-mentioned Table 1. As is clear from the test results in Table 1, in Sample 5, the effect of not binding the fiber bundles 4B together and the effect of forming the coating film 7 were recognized.

Further, in each of the above embodiments, a tubular body,
Since the tubular body and the portion of the reinforcing fiber in contact with the tubular body are bonded and fixed, high rigidity can be obtained in the swinging direction when used as a flexible joint.

[0040]

In the flexible joint according to the first aspect of the present invention, the reinforcing fiber is provided with a binding preventive member on the winding portion, and the reinforcing fibers are coupled to each other by the rubber elastic body covering the link element. This structure prevents the reinforcing fibers of the winding unit from being integrally bound, and can exhibit stable characteristics from the beginning of production. As a result, in order to stabilize the characteristics, It is possible to eliminate the previously required break-in work.

The flexible joint according to claim 2 of the present invention comprises:
By coating the outer peripheral surface of the winding portion of the reinforcing fiber with a coating film and impregnating the inside thereof with a lubricating liquid, it is possible to prevent wear and damage due to friction between the reinforcing fibers in the winding portion. .

The flexible joint according to claim 3 of the present invention comprises:
It is possible to prevent the reinforcing fibers of the winding portion from being integrally bound by the covering material that covers the reinforcing fibers of the winding portion so as to be relatively displaceable.

The flexible joint according to claim 4 of the present invention comprises:
The reinforcing fibers in the winding section are covered with a covering material so as to be relatively displaceable, and the outer peripheral surface of the winding section is further covered with a coating film, whereby the reinforcing fibers in the winding section are integrally bound. This can be prevented more reliably, and at the same time, it is possible to prevent wear and damage due to friction between the reinforcing fibers in the winding portion.

In the method for manufacturing the flexible joint according to the fifth aspect of the present invention, the coating film is formed on the outer peripheral surface of the winding portion of the reinforcing fiber, and then the inside of the coating film is impregnated with the lubricating liquid.
Preventing the reinforcing fibers of the winding part from being integrally bound by the rubber elastic body, exhibiting stable characteristics from the beginning,
In addition, it is possible to manufacture a flexible joint that is free from wear and damage due to the friction between the reinforcing fibers in the winding portion.

According to a sixth aspect of the present invention, in the method for manufacturing a flexible joint, the winding portion of the reinforcing fiber is impregnated while changing the distance between the pair of tubular bodies around which the reinforcing fiber is wound. By hardening the coated molten material, the reinforcing fibers of the winding portion are relatively displaceably covered, and the reinforcing fibers of the winding portion are prevented from being integrally bound by the rubber elastic body. A flexible joint exhibiting stable characteristics can be manufactured.

[Brief description of drawings]

FIG. 1 is a plan view of a flexible joint according to a first embodiment of the present invention.

FIG. 2 is a plan view of the elastic link shown in FIG.

FIG. 3 is an enlarged cross-sectional view of a main part for explaining an example of the manufacturing method of the present invention.

FIG. 4 is an enlarged cross-sectional view of a main part for explaining another example of the manufacturing method of the present invention.

[Explanation of symbols]

 1, 2 Inner cylinder member 3 Outer cylinder member (cylindrical body) 4 Reinforcing fibers 4A, 4B Reinforcing fiber bundle 5 Rubber elastic body 6 Silicon oil (lubricant) 7 Coating film 8 Adhesive 10 Flexible joint L Elastic link P contact Part Q Winding part

Claims (6)

[Claims] 1. A flexible joint in which a link element formed by winding a reinforcing fiber a plurality of times between a pair of cylindrical bodies provided on a drive shaft side and a driven shaft side is covered with a rubber elastic body, A tubular body and a portion of the reinforcing fiber that is in contact with the tubular body are adhesively fixed, and the reinforcing member is reinforced by the rubber elastic body on the winding portion of the reinforcing fiber located between the pair of tubular bodies. A flexible joint provided with an anti-bonding material for preventing bonding between fibers. 2. The binding preventing member is a coating film that coats the outer peripheral surface of the winding portion of the reinforcing fiber, and a lubricating liquid that impregnates the winding portion inside the coating film. The flexible joint according to claim 1, which is characterized in that. 3. The flexible joint according to claim 1, wherein the coupling preventing member is a covering material that covers the reinforcing fibers of the winding portion so as to be relatively displaceable. 4. The coupling preventing member is a coating material that covers the reinforcing fibers of the winding portion so as to be relatively displaceable, and a coating film that covers the outer peripheral surface of the winding portion. The flexible joint according to Item 1. 5. A method for manufacturing a flexible joint in which a link element formed by winding a reinforcing fiber a plurality of times between a pair of cylindrical bodies provided on the drive shaft side and the driven shaft side is covered with a rubber elastic body. In manufacturing the link element, the pair of tubular bodies and the portion of the reinforcing fiber that is wound between the pair of tubular bodies and is in contact with the pair of tubular bodies are adhesively fixed. After that, after forming a coating film on the outer peripheral surface of the winding portion of the reinforcing fiber located between the pair of tubular bodies, a lubricating liquid is applied to the winding portion inside the coating film. A method for manufacturing a flexible joint, characterized by impregnating. 6. A method for manufacturing a flexible joint in which a link element formed by winding a reinforcing fiber a plurality of times between a pair of cylindrical bodies provided on a drive shaft side and a driven shaft side is covered with a rubber elastic body. In manufacturing the link element, the pair of tubular bodies and the portion of the reinforcing fiber that is wound between the pair of tubular bodies and is in contact with the pair of tubular bodies are adhesively fixed. After that, after impregnating the wound portion of the reinforcing fiber positioned between the pair of tubular bodies with the coating liquid material, the coating liquid material is changed while changing the distance between the pair of tubular bodies. A method for manufacturing a flexible joint, which comprises curing.