JPS5940636Y2 - Nipple fixed connection structure to flexible hose end - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure in which a nipple is fixedly connected to the end of a flexible hose whose outer circumferential surface is formed in a continuous wave shape along the axial direction. In contrast, the present invention relates to a structure for fixedly connecting a nipple to an end of a flexible hose, which can prevent the nipple and the hose from falling off from each other or preventing fluid from leaking from this fixed connection.

In this type of structure for fixing the nipple to the end of a flexible hose, in order to improve the adhesion between the nipple and the inner surface of the hose, an outer cylinder is provided that fits onto the hose, and this outer cylinder and nipple connect the hose. The practice was to squeeze the

In such a configuration, strong compressive stress acts on the end of the hose, and concentrated shear stress acts on the boundary between the pinched portion and the non-squeezed portion.

Since the main use of this type of flexible hose is to bend it, it has the disadvantage that the boundary is easily damaged when such bending force is applied.

The flexible hose has a disadvantage in that it is easily damaged when high-pressure fluid is passed through it, and for this reason, it has been necessary to make the hose itself extra strong.

In view of these drawbacks, the present invention has been developed to provide a flexible hose end that is not easily damaged even though the hose end is compressed between the nipple and the outer cylinder, and that allows for extremely easy mutual connection between the flexible hose and the nipple. The purpose is to provide a nipple fixed connection structure to.

The present invention has a officially registered structure for fixing a nipple to the end of a flexible hose, in which the outer peripheral surface of the cylindrical portion of the nipple inserted into the hose is formed into a tapered surface with a smaller diameter on the front end side in the direction of insertion. The minimum outer diameter of the front end in the insertion direction,
A cylindrical body that has approximately the same inner diameter as the hose, has a protrusion on the inner surface that fits into the wavy outer peripheral surface of the hose, and is configured separately from the insertion cylindrical portion, and the nipple. A fixing structure for fixing each other is provided, and in this fixing position, the length of the insertion tube part is set so that the minimum diameter end thereof protrudes beyond the tube body in the axial direction of the hose, and a protrusion is provided on the inner surface. The wavy protrusions of the hose are engaged with the cylindrical body having a plurality of pitches, so that the following effects are achieved.

In other words, from the minimum outer diameter end of the nipple to the end of the cylinder, the hose end receives only the expansion force from this nipple cylinder, and since this is a tapered surface, this expansion force gradually decreases. In addition, the cylindrical body and the flexible hose are arranged so that the protrusions on the inner surface of the cylindrical body and the wavy protrusions of the flexible hose engage with each other over multiple pitch forces, so that the axis of the flexible hose is Since the elongation in the direction is strongly regulated and used synergistically, no concentrated shear stress is applied to the hose portion where the minimum outer diameter end exists.

Continuing from the part where the expansion force was increased in this way,
Since it is pressed and pinched from the outside by the cylindrical body, no concentrated shear stress is generated even at the boundary between the pinched parts.

Furthermore, by making the nipple long in this way, when the hose is bent, the bending starts at the tip of the nipple, and since there is no cylindrical body at this location, the cylindrical body acts on the inside of the bend, and as a result, the hose There is no force acting to bend the cross section in the direction opposite to the arc of the cross section, and there is no longer a sudden bend on the side in the bending direction.

In other words, the hose is held in such a way that large concentrated shear stress does not occur at its ends, so even if the hose is bent, excessive shear stress will not occur locally, so the hose will not break. This is significantly less than before.

Moreover, since the nipple and the cylinder are constructed separately, for example, as detailed in the embodiment, the cylinder is first screwed onto the end of the flexible hose, and then the nipple is inserted. It has become possible to connect the hose by inserting it into a flexible hose, for example, when the nipple and cylinder are integrally constructed, the hose can be connected against the clamping force between the nipple and the cylinder. This makes the connection operation extremely easy compared to screwing and screwing in against a clamping force that increases as the screwing depth increases.

Embodiments of the present invention will be explained based on the drawings. Figures 1 and 2 illustrate a nipple fixed connection structure to a flexible hose according to the present invention. A flexible hose 2 is made of metal and has a cylindrical portion 2A for insertion into the end of the hose and a flange portion 2B. It is a nipple, and the inner diameter of the cylindrical portion 2A is the same as that of the flexible hose 1.
It is set slightly smaller than the inner diameter of the cylinder part 2.
The outer circumferential surface 2a of A is a tapered surface such that the outer diameter at the tip, that is, the deepest insertion part is slightly smaller than the inner diameter d of the hose 1, and the outer diameter gradually increases as it reaches the flange portion 2B side. It is formed.

It is desirable that the corner between the tip end surface and the outer circumferential surface of the cylindrical portion 2A be slightly rounded.

3 is a cylinder whose inner circumferential surface is in contact with spiral protrusions 3a having a helical pitch equal to the helical pitch of the valley portions 1a.

A plurality of bolts 3b, which penetrate in the radial direction, are screwed onto one end of this cylinder 3, and on the other hand, the bolts 3b, . A circumferential groove 2b into which the inner ends of the hoses 2 and 3 can be fitted and locked is formed, thereby forming a fixed structure 4 that restricts relative movement of both 2 and 3 in the hose axis direction.

In this fixed state, the length corresponding to the small diameter side end of the nipple 2 is set to the length of the cylindrical portion 2A so as to protrude from the cylindrical body 3.

Next, the connection procedure will be described. First, the cylindrical body 3 is fitted onto the end of the flexible hose 1 to a predetermined position while being rotated so that the protrusions 3a are screwed into the troughs 1a.

That is, as shown in the figure, the cylindrical body 3 and the flexible hose 1 are connected,
The cylindrical body 3 is externally fitted so that the protrusions 3a of the cylindrical body 3 and the wavy protrusions of the flexible hose 1 are screwed into each other by a large number of pitches.

In this state, the cylindrical portion 2A of the nipple 2 is forcibly inserted into the end of the flexible hose 1 by the driving force of the hydraulic system.

Since the outer circumferential surface 2a of the cylindrical portion 2A is a tapered surface, the flexible hose 1 is expanded and deformed outward in the radial direction with this insertion, and the outward expansion deformation beyond a certain amount is prevented from occurring in the cylindrical portion. Since the inner circumferential surface of the flexible hose 1 is regulated by contact with the inner circumferential surface of the body 3 and the protrusions 3a, the inner circumferential surface of the flexible hose 1 is
tightly adheres to the outer peripheral surface of the

When the cylindrical part 2A is inserted to the specified depth, the port) 3b.
. . , and its inner end is fitted into the circumferential groove 2b.

As a result, the cylindrical body 3 and the nipple 2 are integrated, and the friction force between the flexible hose 1, the cylindrical portion 2A, and the cylindrical body 3 is mechanically engaged with the projections 3a and the valleys 1a. flexible hose 1
The flexible hose 1 shown in the figure is constructed by embedding a spiral hard resin reinforcing material in the thickness of the soft synthetic resin a, but the material and shape etc., may be set appropriately and are not limited to the illustrated structure.

Moreover, although the inner peripheral surface of the cylinder 3 is formed as a cylindrical surface parallel to the axis, it may be slightly inclined in the same direction as the tapered surface of the cylinder portion 2A.

FIG. 3 shows an embodiment in which the cylindrical body 3 has a two-sided structure, and one end of a pair of semi-cylindrical bodies 3A, 3B is provided with bent portions 5a, 5b that engage with each other in a swingable manner, Each semi-cylindrical body 3A has projecting pieces 6a and 6b connected to each other by bolting at the other end.

An arc-shaped metal rod is placed on the inner surface of the cylindrical body 3A,
When 3B are connected in a cylindrical shape, a series of spiral protrusions 3a
They are welded in such a manner that they form...

FIG. 4 shows another embodiment, in which spiral projections 3a are formed by bending the cylindrical body 3.

Although not shown, the protrusions 3a are not formed in a series of spiral shapes, but instead are formed into a plurality of interrupted protrusions that fit into the valleys 1a on the outer circumferential surface of the flexible hose 1 at appropriate intervals in the circumferential direction. It is also possible to implement it by configuring it into a group of protrusions.

Furthermore, in any of the above embodiments, a flange-shaped protrusion facing the flange portion 2B of the nipple 2 is provided on the outer peripheral surface of the cylinder 3, and the protrusion and the flange portion 2B are moved closer to each other by a hydraulic device. Accordingly, it is possible to configure the nipple 2 to be inserted into the hose 1.

[Brief explanation of drawings]

The drawings show an embodiment of the nipple fixed connection structure to the flexible hose end according to the present invention, and FIG. 1 is a partially cutaway front view, and FIG.
The figures are a sectional view taken along the line ■--■ in FIG. 1, FIG. 3 is a side view of the cylinder showing another embodiment, and FIG. 4 is a partially cutaway front view of the cylinder showing another embodiment. 1...Flexible hose, 1a...Tanibe, 2
...Nipple, 2A ...Cylinder part, 2a
...Outer peripheral surface, 3...Cylinder, 3a...
...Protrusion, 4...Fixed structure.

Claims (1)

[Claims for Utility Model Registration] ■ A structure in which a nipple 2 is fixedly connected to an end of a flexible hose 1 whose outer peripheral surface is formed in a continuous wave shape along the axial direction, and the hose 1 of the nipple 2 The outer peripheral surface 2a of the cylindrical portion 2A for insertion into the hose 1 is formed into a tapered surface with a smaller diameter at the front end in the insertion direction, and the minimum outer diameter at the front end in the insertion direction is approximately the same as the inner diameter d of the hose 1. In addition, it has a protrusion 3a on the inner surface that fits into the wave-shaped outer circumferential surface of the hose 1, and the insertion tube portion 2A.
A fixing structure 4 is provided that fixes the nipple 2 and a cylindrical body 3 that is configured separately from the cylindrical body 3 to each other. is set to protrude beyond the cylindrical body 3 in the axial direction of the hose 1, and the wavy protrusions of the hose 1 are engaged with the cylindrical body 3 having protrusions 3a on the inner surface by a number of pitches. Nipple fixed connection structure to flexible hose end. (2) A structure for fixing a nipple to an end of a flexible hose according to claim (2), wherein the outer circumferential surface of the hose 1 and the protrusion 3a are formed in a continuous spiral waveform.