JP2646030B2 - Method of manufacturing bent hose - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a bent rubber hose used for a hot water pipe, a fuel pipe, and other machines of an automobile.

[Conventional technology]

In the case of a rubber hose having no reinforcing layer, a bent hose can be manufactured by injection molding using a mold. However, in this method, since the hoses are made one by one, the production efficiency is not good. A hose with a reinforcing layer cannot be manufactured in this way.

Therefore, a hose made of only rubber without a reinforcing layer or a hose with a reinforcing layer is continuously formed using an extruder or a braiding machine for a reinforcing layer, and is cut into a required length to form a bent mandrel. One by one is inserted into the outer periphery, put into a vulcanization can, vulcanized, and after vulcanization, pulled out from the mandrel to produce a bent hose.

In this method, it is necessary to apply a release agent to facilitate insertion of the hose around the outer circumference of the bent mandrel, and it is difficult to automate the process of inserting and extracting the rubber hose into the mandrel. And there is a problem that the release agent attached to the hose needs to be washed.

[Problems to be solved by the invention]

In view of the fact that the above-mentioned conventional method has a problem that a mandrel is used as a bending mold, an object of the present invention is to provide a method for manufacturing a bent hose that does not use a mandrel.

[Means for solving the problem]

The present invention provides: (1) a filling step of filling a filler inside a semi-vulcanized linear hose, a frame fitting step of bending and inserting the hose after the filling step into a bending frame, and a hose having a frame fitting step A vulcanizing hose having a vulcanizing step, a discharging step of taking out the hose after the vulcanizing step from the bending frame and discharging the filler from the hose, and (2) a semi-vulcanized linear shape Fitting step of bending and inserting the hose into the bending frame, filling step of filling the hose into the hose after the frame fitting step, vulcanizing step of vulcanizing the hose after the filling step, and hose after the vulcanizing step And a discharge step of discharging the filler from the inside and removing the filler from the bending frame.

A semi-vulcanized straight hose is formed by extruding a rubber material for molding into a tube with an extruder, winding it up on a plate, placing it in a vulcanizing tube, semi-vulcanizing it, and setting it to the required length. Get cut. In the case of having a reinforcing layer, a rubber material for molding is obtained by extruding an inner rubber layer into a tube by an extruder, applying a reinforcing layer on the inner rubber layer, and forming an outer rubber layer on the outer periphery thereof. Water is sealed in a pressurized state in a heated hose, lead is applied to the outside, semi-vulcanized, and after removing the lead, the water sealed inside is discharged and cut to the required length. .

As the filler used in the invention (1) of the present application, solid particles such as glass beads, steel balls, resin balls, and ceramic balls can be used. The diameter of the sphere is preferably 0.5 to 3 mm. If the powder is a fine powder such as flour, the slip between particles becomes worse, and it becomes difficult to bend when bending the hose after filling. If the particle size is large, after vulcanization, a concave spherical mark remains on the inner surface of the hose. The particles are easily bent when those having good mutual slip bend.

As the filler used in the above invention (2) of the present application, fluids such as gas and liquid can be used, but water and air are inexpensive and need not be cleaned after use. The fluid is spiked at one end of the hose, a stopper with a cock is attached at the other end, the cock is opened and sealed under pressure, the cock is closed and separated from the pressurized fluid supply device and the cock portion, and the continuous vulcanizing device Put in.

[Action]

The bending process of the semi-vulcanized material in advance in the present invention is
By semi-vulcanizing, the rubber is less likely to be damaged in the cutting step, the filling step, and the frame fitting step, and the bent portion is less likely to be flat when bent. This half vulcanization is 150
℃, 4 minutes or less is good. Under the vulcanization conditions above, even when bending and vulcanization is completed, when the hose is removed from the bending frame, the bending angle of the hose becomes larger due to the elasticity of the rubber than the bending angle of the bending frame. Under semi-vulcanization conditions of less than one minute, this return angle can be suppressed within 5 °, and a hose bent to a required angle can be obtained by adjusting the bending angle of the bending frame.

The reason why the filler is sealed in the hose in the present invention is to prevent the bent portion from becoming flat when the hose is put in a bending frame. The bending frame may be used by combining the two divided along the length of the curved tube, or it may be a trough-shaped one, and the hose may be bent and inserted into the bending frame. Is also easy.

By using a material that does not contaminate the hose as a filler, it is not necessary to clean the mold release agent and the mold release agent, which are conventionally required.

〔Example〕

Example 1 In the unvulcanized hose forming step 1 shown in FIG. 1, rubber was continuously extruded into a cylindrical shape having an inner diameter of 16 mm and an outer diameter of 24 mm using an extruder to obtain a hose having a length of 300 m. The semi-vulcanization step 2 was performed in which the hose was wound up on a plate while being extruded, placed in a vulcanization can, and subjected to primary vulcanization at 150 ° C. for 3 minutes. Cutting step 3 for cutting the hose after semi-vulcanization step 2 into 60 cm lengths
Then, as shown in FIG. 2, a rubber stopper 10 was provided at one end of each hose 8, and glass beads having a diameter of 1 mm were filled as filler 9 from the other end, and the stopper 10 was provided. As shown in FIG. 3, the hose after the filling step 4 is inserted into a bending frame 11 composed of a semicircular groove bent into a crank shape at an angle of 85 ° as shown in FIG.
A frame fitting step 5 for fixing the bent portion with a press having a semicircular inner cross section was performed, and a vulcanizing step 6 for vulcanizing at 165 ° C. for 30 minutes using a continuous vulcanizing apparatus was performed. After the vulcanization step 6, the hose 8 was removed from the bending frame 11, and the internal filler 9 was discharged to obtain a bent hose. The two bend angles of this hose are
At 90 °, the ratio of the minor axis to the major axis of the bent portion was 0.95.

Example 2 An unvulcanized rubber hose having an inner diameter of 12.7 mm and an outer diameter of 17.2 mm and having a reinforcing layer braided with polyester fibers in the middle was produced by a conventional method, and was semi-vulcanized in the same manner as in Example 1. Next, the hose was cut into lengths of 60 cm each, bent in a crank shape at an angle of 85 °, opened in a bending frame composed of a metal tube divided in two along the length direction, and bent and inserted into the inside. At both ends of this bending frame, subjected to metal plug at one end of the hose is subjected to plug with Kotsuku at the other end, the water enclosed in 5 kg / cm ² pressure through Kotsuku with open Kotsuku, close the Kotsuku The hose connected to the pressurized water supply was removed. This was put into a continuous vulcanizing apparatus and vulcanized at 165 ° C. for 45 minutes. The water taken out of the vulcanizer and put into the hose was discharged and removed from the bending frame.

The bending angle of the obtained hose was 90 ° and the bending angle was almost a perfect circle. Further, no pores were generated between the reinforcing layer and the inner and outer rubber layers.

〔The invention's effect〕

Since the method of the present invention is a bending method using an outer die that does not use a mandrel, the application of a release agent in the conventional method and the cleaning of the release agent attached to the product are not required, and the insertion and removal of a hose into and from a mandrel can be performed. In addition, it is possible to manufacture a hose having a curved shape by a method that requires less labor than a conventional method, for example, it can be performed by a mold fitting with less labor.

[Brief description of the drawings]

FIG. 1 is a process diagram of Embodiment 1 of the present invention, FIG. 2 is a partial cross-sectional side view of a hose in which filler is packed in a hose, and FIG. 3 is a plan view of the hose fitted in a bending frame. It is. 1. Unvulcanized hose forming process 2. Semi-vulcanizing process 3, Cutting process 4. Filling process 5, Frame fitting process 6. Vulcanizing process 7, Ejecting process 8. Hose , 9 ... filler 10 ... plug, 11 ... bending frame

Claims (2)

(57) [Claims] 1. A filling step of filling a filling material into a semi-vulcanized straight hose, a frame fitting step of bending and inserting the hose after the filling step into a bending frame, and a hose having a frame fitting step. A method for producing a bent hose, comprising: a vulcanizing step of vulcanizing, and a discharging step of taking out a hose after the vulcanizing step from a bending frame and discharging a filler from the inside of the hose. 2. A frame fitting step in which a semi-vulcanized linear hose is bent and inserted into a bending frame, a filling step in which a filling material is filled in the hose after the frame fitting step, and a hose which has passed through the filling step. A method for producing a bent hose, comprising: a vulcanizing step of vulcanizing; and a discharging step of discharging a filler from the inside of the hose after the vulcanizing step and removing the filler from a bending frame.