JP2562340B2 - How to make a hose with protector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a method for manufacturing a hose with a protector used for a heater hose or the like for an automobile.

(Prior Art) In recent years, a hose attached to an automobile is required to have a complicated shape and a long hose length as the number of other parts increases and the arrangement thereof becomes complicated. In many cases, it is necessary to assemble a protector on the outer peripheral surface to protect the.

As a method of manufacturing such a hose with a protector, as shown in FIG. 6, a hose 11 is provided with a protector 12 having half cracks in the longitudinal direction on the outer circumference of the hose 11 which is vulcanized to have a predetermined bending shape. There is a method of assembling and covering along the same, and fixing and fixing the outer circumference of the protector 12 with a tape 14 at a plurality of places.

As another manufacturing method, as shown in FIG. 7, a straight protector 13 made of vulcanized rubber is inserted into a hose 11 which has been vulcanized to have a predetermined bending shape, as shown in FIG. There is a way.

(Problems to be Solved by the Invention) Among the above conventional manufacturing methods, the product obtained by the former manufacturing method has a poor appearance because the protector 12 does not come into close contact with the outer peripheral surface of the hose 11, and the latter manufacturing method has Due to the elasticity of rubber, the bent portion R of the hose 11 expands, so that the desired product is not obtained, and in both production methods, there are problems that clips for fixing pipes to both ends of the hose 11 cannot be easily obtained. It was

An object of the present invention is to solve the above problems, to provide a method of manufacturing a hose with a protector, in which the protector and the hose have a good close contact with each other, and which has an excellent appearance and in which a portion for attaching a clip to the end of the hose can be easily obtained. is there.

Structure of the Invention (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention draws an unvulcanized protector in the longitudinal direction from the outer peripheral surface of an unvulcanized long hose. The gist is a method for producing a hose with a protector, which is characterized in that the hose with a protector is characterized in that it is covered while being stretched, cut into a predetermined length, and inserted into a mandrel having a predetermined curved shape and vulcanized.

(Operation) By adopting the above configuration, by covering the protector in the unvulcanized state while stretching it in the longitudinal direction, the protector is brought into close contact with the entire outer peripheral surface of the hose, and the hose when cut to a predetermined length. The protectors at both ends shrink, and the protectors shrink further by inserting into the mandrel and vulcanizing.
Both ends of the hose will have no protectors.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a long hose 1 which is wound.
Is fed to the front through a feed roller 2 having three rollers above and below. The hose 1 is an unvulcanized rubber made of ethylene / propylene / diene copolymer (EPDM) and reinforced with synthetic fibers. The dimensions are 16 mm inside diameter and 24 mm outside diameter. A container 3 filled with a release agent L is disposed at the tip of the feed roller 2, and the container 3
A pressing member 4 for pressing the hose 1 and immersing the hose 1 in the release agent L is provided above. The release agent L is a 20 to 30 wt% aqueous solution of silicone. As the mold release agent L, one normally used in resin molding is used.

An extruder 6 for coating the protector 5 on the outer peripheral portion of the hose 1 is arranged at the tip of the container 3. The protector 5 is unvulcanized rubber, and the same EPDM as the hose 1 is used. At the tip of the extruder 6, a pulling roller 7 having the same structure as the feed roller 2 is arranged. The hose 1 having the protector 5 coated on the outer peripheral portion pulled by the pulling roller 7 is wound by the winding portion T.

Next, a method of manufacturing a hose with a protector using the apparatus configured as described above, and its operation and effect will be described.

As shown in FIG. 1, first, the rolled unvulcanized
A hose 1 made of EPDM is fed by a feed roller 2 at a predetermined speed. The hose 1 sent by the feed roller 2 is
The release agent L in the container 3 is pressed downward by the pressing member 4.
It is dipped in and the release agent L is attached to the outer peripheral surface thereof. The hose 1 to which the release agent L is attached is sent to the extruder 6.

In the extruder 6, EP which is a raw material of the protector 5
DM is supplied, extruded while being heated and melted, and coated on the outer peripheral surface of the hose 1. Then, the hose 1 covered with the protector 5 is pushed out at a predetermined speed.

The hose extruded from the extruder 6 is pulled by the pulling roller 7. At this time, the pulling speed by the pulling roller 7 is set to be about 10% faster than the pushing speed of the protector 5 by the extruder 6. Therefore, the protector 5 at the outer portion is further pulled in the longitudinal direction as compared with the hose 1 at the inner peripheral portion, and the strain in the pushing direction of the protector 5 becomes large. The hose 1 pulled by the pulling roller 7 is sequentially wound around the winding portion T. that time,
Since the protector 5 exerts a force of contracting on the hose 1, the tip of the hose 1 is fixed together with the protector 5 so that the protector 5 does not contract at the winding portion T.

When the hose 1 thus wound up is cut into length units of 300 mm, as shown in FIGS. 2 (a) and 2 (b), the release agent L is formed on the outer peripheral portion of the hose 1 at the center. The hose 1 is covered with a protector 5 on its outer peripheral portion, and the protector 5 is in close contact with the hose 1 via the mold release agent L without a gap. The length for cutting the hose 1 is appropriately selected within the range of about 100 to 500 mm depending on the conditions such as the use and the place of use. The end of the protector 5 is inside the end of the hose 1. That is, the end of the protector 5 is shortened at the end of the hose 1 due to contraction. This is because, as described above, the protector 5 is wound in a state of being pulled more than the hose 1, so that a force that contracts at both ends acts at the time of cutting. Moreover, even if the protector 5 is cracked,
It has a function of preventing the crack from propagating to the hose 1. Therefore, it is not preferable that the protector 5 and the hose 1 are completely bonded.

The hose 1 coated with such a protector 5 is
As shown in FIG. 3, the mandrel 8 having a predetermined shape is inserted from one end to the state shown in FIG. Then add this to 150
Vulcanize at 30 ° C for 30 to 60 minutes. Then, the end portion of the protector 5 further contracts with respect to the end portion of the hose 1 due to vulcanization, and the total contraction amount becomes 20 to 30 mm. The pressure of the protector 5 is about 2 mm.

Therefore, as shown in FIG. 5, when the mandrel 8 is removed and metal pipes 9 are connected to both ends of the hose 1,
A clip 10 having a length of 10 to 15 mm for fixing the pipe 9 and the hose 1 is easy to attach.

As described above, according to the method for manufacturing the hose with the protector of the present embodiment, the protector 5 is extruded on the outer peripheral surface of the hose 1 by the extruder 6 and stretched by the pulling roller 7. Good appearance and excellent appearance. Also, since the protector 5 contracts with respect to the end of the hose 1 during cutting and vulcanization, the clip 10 is attached to the end of the hose 1.
The mounting part is obtained at the same time when the vulcanization is completed.

The present invention is not limited to the above embodiment, but may be configured as follows.

(1) As a method of changing the shrinkage ratio of the protector 5 with respect to the hose 1, there is a method of appropriately changing the pulling speed of the protector hose in the pulling roller 7 with respect to the extrusion speed of the protector 5 in the extruder 6. That is, if the pulling speed of the hose with the protector in the pulling roller 7 is made larger than the extrusion speed of the protector 5 in the extruder 6, the shrinkage rate of the protector 5 can be increased, and conversely the pulling speed can be decreased. If so, the shrinkage rate can be reduced.

It is also possible to change the shrinkage rate of the protector 5 with respect to the hose 1 by changing the vulcanization conditions.

In this way, by changing the contraction rate of the protector 5 with respect to the hose 1, the end of the protector 5 is made shorter than the end of the hose 1 by a predetermined length, and the desired clip 10 is attached to the hose 1 at that part. Can be installed.

(2) As the material for the hose 1, EPDM was used in the above embodiment, but natural rubber, styrene
Butadiene copolymer rubber (SBR), butadiene rubber (B
R), acrylonitrile-butadiene copolymer rubber (NB
R), epichlorohydrin rubber or the like is used, and as the material of the protector 5, chloroprene rubber (CR), acrylic rubber, or other solid rubber is used in addition to EPDM of the above-mentioned embodiment.

(3) The hose with a protector obtained by the present invention is
It is suitable for use in not only heater hoses for automobiles but also brake hoses, cooler hoses, fuel hoses, radiator hoses, etc.

EFFECTS OF THE INVENTION According to the method for manufacturing a hose with a protector of the present invention, the protector and the hose have good adhesiveness, have an excellent appearance, and have an excellent effect that a portion for attaching a clip to the end of the hose can be easily obtained.

[Brief description of drawings]

1 to 5 are views showing an embodiment of the present invention, and FIG. 1 is a schematic front view showing a manufacturing process of a hose with a protector,
2 (a) is a sectional view of the hose covered with a protector, FIG. 2 (b) is a side sectional view of FIG. 2 (a), and FIG. 3 is a hose covered with a protector inserted into a mandrel. Partial cross-sectional view showing the state, FIG. 4 is a partial cross-sectional view showing the state in which the hose covered with the protector is inserted into the mandrel and vulcanized, and FIG. 5 is the state in which the hose with the protector is attached with piping. Partial cross-sectional view shown, FIGS. 6 to 8 are views showing a conventional example, FIG. 6 is a front view of a hose using a half protector, and FIG. 7 is a vulcanized hose in an unvulcanized state. FIG. 8 is a partial cross-sectional view showing a state in which the protector is inserted, and FIG. 8 is a partial cross-sectional view showing a state in which the unvulcanized protector is inserted into the vulcanized hose. 1 ... long hose, 5 ... roller, 8 ... mandrel, L ... release agent

Claims (3)

(57) [Claims] 1. An unvulcanized long hose (1) is coated on the outer peripheral surface of an unvulcanized protector (5) while being stretched in the longitudinal direction, and then cut into a predetermined length. A method of manufacturing a hose with a protector, which comprises fitting into a mandrel (8) having a predetermined curved shape and vulcanizing. 2. When cut to a predetermined length, the end of the protector (5) is shortened at the end of the hose (1) due to contraction, and when vulcanized, the end of the protector (5) is further shortened. The method for producing a hose with a protector according to claim 1, wherein the end portion of (1) is shortened due to contraction. 3. The method for producing a hose with a protector according to claim 1, wherein the unvulcanized long hose (1) has an outer peripheral surface coated with a release agent L.