JPS6235191A - Bellows hose and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bellows hose and a method for manufacturing the same. In particular, it relates to bellows hoses that have certain tensile properties and are required to have a linear relationship between elongation and tensile force, and are used for flotation adjustment, for example, as supernatant water discharge pipes in batch-type activated sludge treatment equipment. The present invention relates to a bellows hose that is most suitable for bellows hoses and a method for manufacturing the same.

(Prior art) A conventional bellows hose and its manufacturing method are disclosed in Japanese Patent Application Laid-open No. 5
The invention described in Japanese Patent No. 7-204386 and the invention shown in FIG. 5 are known.

The former is a bellows hose that is made of a rubber-like material of uniform thickness with a reinforcing layer provided in the middle, and has a cord shaped like a bellows, and the reinforcing layer is arranged approximately at right angles to the axis. In addition, the manufacturing method is to form a cylindrical hose molded body by sequentially overlapping and winding an inner layer rubber, an intermediate cord reinforcing layer, and an outer layer rubber on a mandrel in which circumferential grooves and circumferential protrusions are formed alternately. The hose molded body is made into an uneven shape that matches the uneven surface of the mandrel by tightening the string-like body at the corresponding positions, and is then vulcanized.

On the other hand, as shown in FIG. 5, the latter is a bellows hose in which rigid rings 3, which have approximately the same inner diameter as the cylinder 1, are fixed at equal intervals in a rubber cylinder 1 with a reinforcing layer 2 provided in the middle. It is. This bellows hose is made by molding and vulcanizing a rubber cylinder 1 with a reinforcing layer 2 in the middle, and inserting a rigid ring 3 inside the cylinder 1, which has an outer diameter slightly larger than the inner diameter of the cylinder 1. The rigid ring 3 is inserted at intervals and sewn with thread 4 so that the rigid ring 3 does not fall off.

(Problems to be Solved by the Invention) However, in such conventional bellows hoses, the relationship between elongation and tensile force is not constant as shown in Figure 6, and therefore cannot smoothly respond to changes in tensile force. There was a drawback. In addition, the former method uses an expensive mandrel, which increases the product price, and the latter method has wrinkles between the rigid rings, which not only prevent smooth expansion and contraction, but also pose a risk of fluid leaking from the sewn parts. .

An object of the present invention is to provide a bellows hose that eliminates the above-mentioned drawbacks, has a wide expansion/contraction range of elastic deformation, can smoothly respond to changes in tensile force, and does not cause fluid leakage, and a manufacturing method thereof. be.

(Means for Solving the Problems) In order to achieve the above object, the bellows hose of the first invention includes a rigid ring having an outer diameter larger than the inner diameter of the cylinder inside a rubber cylinder of uniform wall thickness. A large number of rigid rings are arranged, and the cylindrical body between the rigid rings is contracted in the axial direction.

Further, the method for manufacturing a bellows hose according to the second invention includes molding a rubber cylinder of uniform thickness with a reinforcing layer provided in the middle on a mandrel, vulcanizing the cylinder, and then removing the mandrel. A plurality of rigid rings having an outer diameter 10 to 20% larger than the inner diameter of the cylinder are inserted into the cylinder, and the cylinder is heat-treated to shrink the cylinder between the rigid rings in the axial direction, and then fixed. It is characterized by the fact that it becomes

Further, a description will be given based on FIGS. 1 to 4 showing the configuration of the present invention. FIG. 1 is a cross-sectional view showing the structure of the bellows hose of the present invention, and FIGS. 2 and 3 are cross-sectional views showing the manufacturing process of the bellows hose of the present invention. In FIG. 2, a rubber cylinder 10 having a uniform wall thickness and having fiber reinforcement N13 provided between an inner rubber 12 and an outer rubber 14 is molded on a mandrel 11. Both ends of the cylindrical body 10 are formed into a predetermined shape depending on the use of the bellows hose. Next, this cylindrical body 10 is vulcanized under predetermined conditions, and then the mandrel 1
1 is removed. During vulcanization, the outer surface of the cylindrical body 10 is wrapped tightly with cloth or the like to prevent bubbles from forming within the rubber. To remove the mandrel 11, the mandrel 11 can be easily removed from the cylinder 1 by blowing compressed air or the like between the mandrel 11 and the rubber cylinder 10.

Next, in the rubber cylinder 10, from the inner diameter of the cylinder 10,
Rigid rings 15 with a 20% larger outer diameter are inserted at predetermined intervals. In this case, as shown in FIG. 3, the rigid ring 15 is inserted almost parallel to the axis of the cylindrical body 10, and one part is brought into contact with the inner surface of the cylindrical body at a predetermined location, and the opposite part is strongly pressed to increase the rigidity. The ring 15 is attached to the rubber cylinder 1
It can be fixed at a predetermined position of 0. When the rigid ring 15 is fixed in this way, the rigid ring 15 is equally pressed by the front and rear cylinders 10, so there is no risk of it falling off. Note that the outer diameter of the rigid ring 15 varies somewhat depending on the material and wall thickness of the rubber cylinder and the reinforcing layer, but if it is too small than the inner diameter of the cylinder, there is a risk that it will fall off during manufacturing, and if it is too large, it may fall off during manufacturing. This makes it difficult to insert the rigid ring into the cylindrical body, so it is preferable that the inner diameter is approximately 10 to 20% larger than the inner diameter of the rubber cylindrical body. Finally, the cylindrical body 10 is subjected to heat treatment (so-called heat setting) under predetermined conditions to shrink the cylindrical body 10 between the rigid rings 15 and 15 in the axial direction of the cylindrical body as shown in FIG. By cooling and fixing, the shape of the rubber cylinder is stabilized.

In addition, the inner rubber 12 and the outer rubber 1 that constitute the rubber cylinder 10
4 and the rigid ring 15 are appropriately selected depending on the usage conditions of the bellows hose, such as temperature and type of fluid.

Further, in the above description, the shapes of the rubber cylinder and the rigid ring are circular, but the present invention is not limited to the above configuration, and may be an elliptical or rectangular bellows hose as necessary. There is no problem.

(Example) A 10 inch diameter mandrel with a thickness of 2.5 mm was made of a chloroprene rubber compound with polyester fibers inserted in the middle.
A bellows hose was manufactured by molding a 5 mm cylinder, vulcanizing it at 155°C for 40 minutes, inserting a stainless steel ring with an outer diameter of 12 inches, and heat-treating it at 150°C for 10 minutes to improve its strength and elongation properties. It was measured.

As a result, the strength and elongation properties were significantly improved compared to the conventional ones, as shown in FIG.

(Effects) Since the bellows hose obtained by the present invention uses an independent rigid ring, it has good tensile properties and has a significantly wider elongation width than conventional hoses.

Moreover, since the rigid rings having an outer diameter larger than the inner diameter of the rubber cylinder are used and the cylinder between the rigid rings is contracted in the axial direction, there is no risk of the rigid rings falling off, and handling becomes easy. In addition, since it is integrally molded, there is no risk of fluid leakage.

This bellows hose has a wide range of usable elongation, so it can be used in fields where a linear relationship between elongation and tensile force is required, such as supernatant water discharge pipes (flotation adjustment bellows) in batch-type activated sludge treatment equipment. It is suitable for use as a hose) and can be moved up and down quickly following the floating state of the drainage trough.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the structure of the bellows hose, Figures 2 and 3 are sectional views showing the manufacturing process of the bellows hose,
FIG. 4 is a diagram showing the tensile characteristics of the bellows hose of the present invention,
FIG. 5 is a sectional view showing the structure of a conventional bellows hose, and FIG. 6 is a diagram showing the tensile characteristics of the conventional bellows hose. 10...Rubber cylinder body, 11...Mandrel, 12.
...Inner rubber, 13...Fiber reinforcement layer, 14...Outer rubber, 15...Rigid ring. Agent Patent Attorney Takeshi Kawakita Cho 10... - Rubber I? 7#, 12...r Outer rubber 13.-m class reinforcement layer 1+...-F rubber j 5°-Rigidity ring Fig. 5 Fig. 6 Fig. D

Claims (3)

[Claims] (1) A large number of rigid rings having an outer diameter larger than the inner diameter of the cylinder are arranged inside a rubber cylinder with uniform wall thickness, and the cylinder between the rigid rings is contracted in the axial direction. Bellows hose. (2) The outer diameter of the rigid ring is 10 mm larger than the inner diameter of the rubber cylinder.
A bellows hose according to claim 1, characterized in that the hose is ~20% larger. (3) A rubber cylinder of uniform thickness with a reinforcing layer provided in the middle is formed on a mandrel, the cylinder is vulcanized, the mandrel is removed, and the inside diameter of the cylinder is 10 to 10 mm thick. 20%
A method for producing a bellows hose, which comprises inserting a plurality of rigid rings having a large outer diameter, heat-treating the cylindrical body to shrink the cylindrical body between the rigid rings in the axial direction, and then fixing the cylindrical body.