DE60021614T2 - RUBBER BRAKE HOSE WITH VERY LOW EXTENSION AND ASSOCIATED METHOD OF MANUFACTURE - Google Patents

Description

TECHNICAL TERRITORY

The The present invention relates to a brake rubber hose, which in the brake of an automobile is used. In particular a brake hose with extremely low elongation, the at a release pressure an extraordinary has low elongation, and a manufacturing process for the same.

STATE OF TECHNOLOGY

In the hydraulic brake of an automobile, the force applied to a brake pedal is converted into a fluid pressure by a master cylinder, and the fluid pressure is transmitted through a brake rubber hose to each wheel cylinder. A conventional brake hose includes a rubber hose and a reinforcing layer made by braiding. 3 Figure 11 is a perspective view of the brake hose with portions thereof cut away. The brake hose includes an inner rubber hose 1 made of brake fluid resistant ethylene-propylene-diene elastomer (EPDM) or styrene-butadiene rubber (SBR), a first reinforcing layer 2 prepared by braiding vinylon fibers as reinforcing fibers, a rubber interlayer 3 made of natural rubber (NR), EPDM or butyl rubber (IIR), a second reinforcing layer 4 made by braiding vinylon fibers and an outer rubber tube 5 made of EPDM or chloroprene rubber (CR).

A method for producing the brake rubber hose having the above structure is as follows. First, the inner rubber tube 1 is extruded around the circumference of a long resin mandrel, and the first reinforcing layer 2 is applied to the outer surface of the inner rubber tube 1 braided. After that, the rubber intermediate layer will be 3 by an extruder on the outer surface of the first reinforcing layer 2 extruded or by wrapping a long rubber band around the layer 2 produced. If the layer 3 by wrapping the rubber band around the layer 2 is made, the second reinforcing layer 4 braided on the tape while the tape is around the layer 2 is wound. Then the outer rubber tube is 5 around the circumference of the second reinforcing layer 4 extruded. These rubber hoses are vulcanized together with your long thorn. After vulcanization, the long mandrel is removed by applying hydraulic pressure. Thereafter, the long rubber tube is cut to a predetermined length and used.

In The past years will be along with the advancement of engine technology the road conditions improves, the speed of a vehicle is increased, thus paying more attention to the performance of a brake is required and it is necessary that the performance of the brake is rigorous standards equivalent. In particular, it is necessary that a braking ability and a brake feel meet strict standards. Within a range of pressures, the exerted on the brake hose become low pressures from 0 to 2.94 MPa associated with the brake feel. it is supposed that the reason why the inner volume of the hose at such low To press is not extended, that lies in the fact that the fibers, which the reinforcing fiber layers pose in the structure of the hose, stretch elastically, but in that the braided reinforcing fibers slip against each other to have. It is also believed that the game is in the braided Fibers have a serious effect on the expansion of the internal volume.

In particular, the expansion of the internal volume by the first reinforcing layer 2 controlled. Consequently, in order to prevent slippage between the braided reinforcing fibers, there has hitherto been used a method comprising braided reinforcing fibers (vinylon fibers) through an adhesive on the outer surface of the inner rubber hose 1 to tie and fasten.

However, the method of bonding and fixing reinforcing fibers to the outer surface of the inner rubber hose by an adhesive has the following problems. That is, as the adhesive, a rubber solution-based vulcanizing adhesive is generally used. Since the rubber solution-based vulcanizing adhesive contains a solvent, it must be dried for a given period of time after being applied to the inner rubber hose 1 was applied. For this reason, the first reinforcing layer 2 not immediately and continuously, after the vulcanizing adhesive on rubber solution base on the inner rubber tube 1 was applied, braided.

Furthermore, the reinforcing fibers themselves are not always bonded to each other, although the amplifiers do not kungsfasern be bound to the inner rubber tube. For this reason, the reinforcing fibers become the first reinforcing layer 2 with the inner rubber hose 1 while they are trapped on the inner rubber tube, allowing the mutual slip between the reinforcing fibers of the first reinforcing layer 2 can not be completely prevented. Therefore, a brake hose with a small elongation can not be easily obtained by bonding the reinforcing fibers of the first reinforcing layer 2 to be reached on the inner rubber hose.

The document DE 2623289 A discloses a multilayer tube for conveying corrosive or abrasive materials. A first reinforcing layer is partially embedded in a backing layer of a thermosetting resin, partially embedded in an adjacent rubber layer.

The The present invention is invented under the above present circumstances Service. It is an object of the present invention to provide the following desired brake hose and a manufacturing method for the same provide.

It an object of the present invention is a brake hose, the complete free from the mutual slip between the reinforcing fiber the first reinforcing layer is to provide and a manufacturing method for the same.

It Another object of the present invention is to completely prevent the mutual slip between the reinforcing fibers of the first reinforcing layer a brake hose with extremely low To provide stretching and a manufacturing method for the same.

EPIPHANY THE INVENTION

Around to fulfill the above tasks The present invention provides a brake hose with extremely low Elongation according to claim 1 ready.

Of the above inner rubber hose can be made of EPDM, the a brake fluid can hardly penetrate, and the outer rubber layer can also be made of EPDM. As reinforcing fibers, which is the first reinforcing layer and the second reinforcing layer can represent Vinylon fibers are used. As a hardening resin that causes is the reinforcing fibers to soak, For example, a melamine resin or a phenolic resin may be used.

Further is a method for producing the brake hose with extremely low Elongation according to claim 4 provided. At the moment of initiation of drinking the reinforcing Fibers with the above curing resin solution a bath is provided which contains a thermosetting resin solution which in capable of reinforcing To impregnate fibers, and a low viscosity has, and the reinforcing fibers become inevitable bathed in the bath, so that the soaking the reinforcing Fibers with the hardening resin solution is initiated. Furthermore, it is preferable that the step of curing the inner rubber tube, the curing resin and the outer rubber tube by vulcanization afterwards is performed on the step of extruding the outer rubber tube.

at the present invention, the mutual slip between the reinforcing fibers the first reinforcing layer, which controls the expansion of the internal volume when a pressure is applied, completely prevented and the strain can be kept low because of the first inner reinforcing layer by inducing the drinking the reinforcing Fibers of the first reinforcing layer with the hardening Resin and curing of the hardening Resin hardened to a massive Layer is made. Therefore, a brake hose, the excellent in brake feel and durability is to be achieved. If the curing resin only on the surface the first reinforcing layer applied and cured is after the first reinforcing layer braided on the inner rubber tube, can be the hardening resin the first reinforcing layer not completely soak, around the surface reach the inner rubber tube, and the resin coating layer is limited in thickness so that the reinforcing fibers are not fully cured can. As a result, mutual slippage occurs between the reinforcing fibers on, and a shift between the reinforcing fibers when a pressure exercised can not be prevented. The first reinforcement layer can become a cured one Layer are made when the curing resin is the inside the reinforcing fibers soaks.

Further, a rubber intermediate layer for preventing abrasion between the first amplifier kung layer and the second reinforcing layer is not needed because the outer surface of the first reinforcing layer, which is cured by the thermosetting resin, has a high abrasion resistance. In addition, a production method in which the extrusion of the inner rubber tube and the braiding of the first reinforcing layer are carried out continuously may be adopted, and such an environmental problem as the air pollution caused by the evaporation of the solvent does not occur because, unlike the prior art, a rubber solution-based vulcanizing adhesive containing a solvent is not used.

SHORT DESCRIPTION THE DRAWINGS

1 is an exploded perspective view of the brake hose according to the present invention.

2 is an illustrative drawing of the manufacturing method according to the present invention.

3 is an exploded perspective view of the conventional brake hose rubber.

BEST WAY FOR IMPLEMENTATION THE INVENTION

In the following, the embodiment of the present invention will be described with reference to the drawings. In 1 denote the reference number 10 an inner rubber hose made of EPDM, which hardly penetrates a brake fluid, 11 a first reinforcing layer made by braiding vinylon fibers around the circumference of the inner rubber tube 10 . 13 a second reinforcing layer made by braiding vinylon fibers around the circumference of the above first reinforcing layer 11 , and 15 an outer rubber tube made of EPDM and the second reinforcing layer 13 covered. The reinforcing fibers comprising the above first reinforcing layer 11 are cured and uniformized by causing the fibers to soak with a melamine resin or a phenolic resin, which is a thermosetting resin that is cured at vulcanizing temperatures.

That is, the above thermosetting resin not only covers the surface of the reinforcing fibers, but also soaks the insides of the reinforcing fibers to cure the reinforcing fibers themselves. Therefore, by the thermosetting resin impregnating the fiber, each of the reinforcing fibers constituting the above first reinforcing layer becomes 11 represent, cured and the reinforcing fibers are combined and constitute a cured layer as a whole. The first reinforcing layer 11 is responsible for the sustaining pressure of the brake hose, and the second reinforcement layer 13 supports the first reinforcement layer 11 just. Therefore, it is sufficient only the reinforcing fibers of the first reinforcing layer 11 cure.

The brake rubber hose having the above structure is manufactured in the following manner. As in 2 shown is the inner rubber tube 10 through an extruder 21 around a long dome 20 extruded, and the first reinforcing layer 11 is through a braiding machine 23 on the outer surface of the above inner rubber hose 10 braided. Thereafter, the above inner rubber tube with the first reinforcing layer braided therearound becomes 11 in a hardening resin solution 25 dipped to allow the above curing resin solution 25 the reinforcing fibers soak. The viscosity of the above curing resin solution 25 is set so low that the above hardening resin solution 25 can impregnate the reinforcing fibers. The inner rubber hose 10 with the first reinforcing layer 11 gets through the pressure rollers 28 and 30 in a resin solution bath 27 be provided inevitably in the curing resin solution 25 dipped and through the hardening resin solution 25 soaked.

After the first reinforcement layer 11 covered and soaked with the thermosetting resin solution is passed through a braiding machine 31 the second reinforcing layer 13 braided, and then by an extruder 32 the outer rubber hose 15 extruded so that he has the second reinforcement layer 13 covered. Thereafter, the thermosetting resin solution that impregnates the first reinforcing layer becomes together with the inner rubber hose 10 and the outer rubber hose 15 vulcanized to cure, as has been conventionally done.

The above manufacturing method is basically the same as the conventional manufacturing method in that the first reinforcing layer and the second reinforcing layer are produced, and at the end, the outer rubber tube is extruded. The above manufacturing method is different than that conventional manufacturing methods in that after your step of braiding the first reinforcing layer 11 instead of extruding a rubber interlayer which has conventionally been practiced, the step of applying the thermosetting resin solution to the first reinforcing layer and submerging the first reinforcing layer in the thermosetting resin solution and omitting the step of extruding the rubber interlayer is provided.

EXAMPLES

When next will be a description of the specific examples of the present Invention given.

In the example, using EPDM, an inner rubber tube was used 10 made having an inner diameter of 3.4 mm and an outer diameter of 5.0 mm. Using a vinyl denier of 1200 deniers, a first reinforcing layer was formed 11 braided by 2 fibers × 20 straps. Thereafter, a melamine resin was caused to be the layer 11 soaks, and the melamine resin, which is the layer 11 soaked, was cured by vulcanization together with the rubber. Using a vinyl denier of 1200 deniers, a second reinforcing layer was formed 13 braided by 3 fibers × 24 straps. Using EPDM became an outer rubber tube 15 manufactured, which had an inner diameter of 8.0 mm and an outer diameter of 10.4 mm.

meanwhile have the inner rubber tube, the first reinforcement layer, the second reinforcement layer and the outer rubber tube of the comparative example have the same structure as those of the example. However, the comparative example differs from the example in that as between the first reinforcing layer and the second reinforcing layer a 0.25-minute thick rubber intermediate layer made of natural rubber was shaped, as is conventional was done, and the first reinforcement layer to the outer surface of the inner rubber hose was tied.

The Experimental results of the example and the comparative example are as follows.

The rubber hoses of the above Example and Comparative Example were for elongation and durability tested. The exam was performed according to JIS D2601. For testing the durability was carried out a whip attempt. The Experimental results are as shown in Table 1.

TABLE 1

As From the above Table 1, the rubber hose of the For example, a smaller elongation than that of the comparative example and is not inferior in durability to that of the comparative example.

COMMERCIAL Applicability

As described above, are the rubber hose with extremely low elongation after according to the present invention and its manufacturing method as a brake hose for to use the hydraulic brake of an automobile which the applied to the brake pedal Force converted by a master cylinder into a hydraulic pressure.

Claims (7)

Very low elongation brake hose comprising: an inner rubber hose ( 10 ), a first reinforcing layer ( 11 ), a second reinforcing layer ( 13 ) and an outer one Rubber layer ( 15 ), wherein a hardening resin which is cured at vulcanizing temperatures, the reinforcing fibers, which the first reinforcing layer ( 11 ), also up to the surface of the first reinforcing layer ( 11 ), wherein the thermosetting resin has been cured together with the reinforcing fibers at vulcanizing temperatures to form the first reinforcing layer ( 11 ) into a solid cured layer. A hose according to claim 1, wherein the thermosetting resin is a melamine resin. A hose according to claim 1, wherein the thermosetting resin is a phenolic resin. A method of making an extremely low elongation brake hose having the following continuous steps: braiding a first reinforcing layer ( 11 ) around an inner rubber hose ( 10 ), dipping the first reinforcement layer ( 11 ) in a thermosetting resin solution capable of impregnating the reinforcing fibers constituting the first reinforcing layer and having a low viscosity so as to cause the thermosetting resin solution to impregnate the reinforcing fibers; Braiding a second reinforcing layer ( 12 ), and extruding an outer rubber coating ( 15 ) on the outer surface of the second reinforcing layer. The method of claim 4, wherein at the step of Making the potion arouse reinforcing fibers with the hardening resin solution a bath is provided which contains a thermosetting resin solution which is capable of reinforcing To impregnate fibers, and a low viscosity has, and the reinforcing Fibers inevitably be soaked in the bath, so that the soaking of the reinforcing Fibers with the hardening resin solution is initiated. A method according to claim 4 or 5, wherein the curing resin solution is a Melamine resin solution or a phenolic resin solution is. Method according to one of claims 4 to 6, wherein the vulcanization step of curing the inner rubber tube, the curing resin and the outer rubber tube subsequently is performed on the step of extruding the outer rubber tube.