JPH0914525A - Low pressure piping hose and low pressure tube for hose - Google Patents

Abstract

PURPOSE: To provide a low pressure piping hose and a low pressure tube for the hose whereby an inserting position of a connecting tube into inner peripheral surface of hose at its end part can be determined easily and also a sealing capability can be improved remarkably by making it difficult for a relative displacement of the connecting tube and the hose to produce. CONSTITUTION: In a low pressure piping hose 1, recessed and protruded parts 2 and 3 are provided on the inner surfaces of the hose at its end part corresponding to the protruded part of the hose through which a connecting pipe with a projected part on its outer periphery surface at the inserting end part is inserted. Also, in a low pressure tube for the hose, the connecting pipe with the protruded part on its outer peripheral surface at its end part is inserted into the end part of the hose 1, and the protruded part is engaged with the recessed and protruded parts 2 and 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hose for low pressure piping and a low pressure piping for the hose.

[0002]

2. Description of the Related Art The spread of automobiles, especially passenger cars, in recent years has been extremely remarkable.

As the passenger cars have been driven by women and elderly people, passenger cars equipped with power steering have come to be widely used.

For this reason, it is required that the power steering can be mounted on a passenger vehicle inexpensively and efficiently.

Low pressure piping work in the power steering system is one of the factors for enabling the power steering system to be mounted on a passenger vehicle inexpensively and efficiently.

FIG. 2 is a vertical sectional view of a hose used for a low pressure pipe of a conventional power steering device.

FIG. 3 is a vertical sectional view of a connecting pipe used for a low pressure pipe of a power steering device.

That is, in the low-pressure piping of the hose of the conventional power steering device, the connecting pipe 4 having the protrusion 5 on the inner peripheral surface of the end of the hose 6 as shown in FIG. 2 and the outer periphery of the end as shown in FIG. Is inserted, and if necessary, it is fastened to the outer periphery by a hose clamp.

However, in such a low-pressure hose pipe of the conventional power steering apparatus, the connecting pipe 4 having the projection 5 on the outer periphery of the end is inserted into the inner peripheral face of the hose 6 whose inner peripheral face is smooth. Since the insertion position is not fixed and the inner peripheral surface of the end of the hose 6 is smooth, the connecting pipe 4
There is a concern that the mutual displacement between the hose 6 and the hose 6 may occur and the sealing performance may deteriorate.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above point, and its object is to solve the above-mentioned drawbacks of the prior art and to connect a hose end inner peripheral surface with a connecting pipe. It is an object of the present invention to provide a hose for low-pressure piping and a low-pressure piping for the hose, in which the insertion position of the hose can be easily determined, and further, the mutual displacement of the connecting tube and the hose is unlikely to occur and the sealing performance can be significantly improved.

[0011]

The gist of the present invention lies in the following two points.

[0012] A low pressure characterized in that a concavo-convex portion is provided on the inner peripheral surface of the end of the hose corresponding to the position of the protruding portion of the hose used by inserting the connecting pipe having the protruding portion on the outer periphery of the insertion end. Piping hose Insert a connecting pipe having a protrusion on the outer periphery of the end into the inner peripheral surface of the end of the hose having an irregular portion on the inner peripheral surface of the end, and engage the protrusion with the irregular portion. Low-pressure hose piping characterized by

[0013]

In the hose for low-pressure piping of the present invention, since the concavo-convex portion is provided at the predetermined position on the inner peripheral surface of the end portion of the hose, the insertion position when the connecting pipe having the protruding portion on the outer periphery of the end portion is inserted is It is easy to determine, and it is possible to prevent the mutual displacement of the hose and the connecting pipe from occurring easily.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the low-pressure piping hose and the low-pressure piping of the hose according to the present invention will now be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing an embodiment of the low pressure piping hose of the present invention.

In FIG. 1, 1 is a hose for low-pressure piping, 2 is a convex portion provided on the inner peripheral surface of the end of the low-pressure piping hose, and 3 is also provided on the inner peripheral surface of the end of the low-pressure piping hose 1. It is a recess.

In the inner peripheral surface of the end portion of the hose 1 for low pressure piping shown in FIG. 1, a connecting pipe 4 having a projection 5 on the outer periphery of the end portion is inserted as shown in FIG. can get.

In this case, the projection 5 of the connecting pipe 4 is the recess 3 provided on the inner peripheral surface of the end of the low-pressure pipe hose 1.
It is configured to penetrate and engage.

In the low-pressure pipe of the hose thus obtained, the protrusion 5 of the connecting pipe 4 enters into the recess 3 provided on the inner peripheral surface of the end of the low-pressure pipe hose 1 and engages with it. Since the inner peripheral surface of the end portion of the low-pressure piping hose also has the convex portion 2, it is difficult to cause the mutual displacement of the low-pressure piping hose 1 and the connecting pipe 4, and as a result, the sealing property of the low-pressure piping of the hose becomes remarkable. Can be improved.

Next, a heat aging test was performed on the thus obtained low pressure pipe of the hose of the present invention and the low pressure pipe of the conventional hose described above.

In the heat aging test, 50 kg / cm ² of high-pressure oil was put into each of the low-pressure pipe of the hose of the present invention and the low-pressure pipe of the conventional hose described above, and then a pressure gauge was attached to one end of the hose. The end side was sealed, and then a heat aging test was performed at 90 ° C. for 300 days. FIG. 4 shows the pressure change between the hose low-pressure pipe of the present invention thus heat-aged and the conventional hose low-pressure pipe described above.

As can be seen from FIG. 4, the conventional hose low-pressure pipe described above tends to gradually decrease in pressure when it is thermally deteriorated at a high temperature of 90 ° C. for a long period of time.

On the other hand, in the hose low-pressure pipe of the present invention, there is almost no decrease in pressure.

[0024]

The low-pressure piping hose of the present invention is provided with the uneven portion at a predetermined position on the inner peripheral surface of the hose end,
The insertion position when inserting the connecting pipe having a protrusion on the outer circumference of the end is easy to be determined, and further, the mutual displacement of the hose and the connecting pipe is less likely to occur, and the sealing property can be remarkably improved. , Industrially useful.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a low pressure piping hose of the present invention.

FIG. 2 is a vertical cross-sectional view of a hose used for low-pressure piping of a conventional power steering device.

FIG. 3 is a vertical cross-sectional view of a connecting pipe used in a low-pressure pipe of a conventional power steering device.

FIG. 4 is a graph showing changes in pressure when heat aging is performed on the low-pressure pipe of the hose of the present invention and the low-pressure pipe of the conventional hose.

[Explanation of symbols]

 1 Hose for low-pressure piping 2 Convex part 3 Recessed part 4 Connection pipe 5 Projection part 6 Hose

Claims (2)

[Claims] 1. A concavo-convex portion is provided on an inner peripheral surface of an end portion of a hose which is used by inserting a connecting pipe having a protruding portion on the outer periphery of the end portion to be inserted and which corresponds to the position of the protruding portion. Characteristic low-pressure piping hose 2. A connecting pipe having a protrusion on the outer circumference of the end is inserted into the inner peripheral surface of the end of a hose having an irregular inner surface on the end, and the protrusion is formed on the uneven portion. Low-pressure hose pipe characterized by being engaged.