JPS5817984Y2 - Connection structure of small diameter metal tube - Google Patents

Description

[Detailed description of the invention] This invention is a metal tube that is often installed as a supply path for oil supply, air supply, etc. in automobiles or various mechanical devices, etc., and has a relatively small diameter of about 30 threads or less. Regarding the improvement of the connection structure, a wedge-shaped inclined receiving surface is provided on the rear surface of the rear opening edge of the straight cylindrical fitting step hole provided at the rear opening edge of the shaft center through hole of the metal joint body. At the same time, the front end edge of a thin metal tube is tightly fitted into the straight cylindrical fitting step hole, and an elastic sealing material such as synthetic resin or rubber is attached to the outer peripheral surface of the thin metal tube. A relatively long sleeve main body is tightly fitted, and a wedge-shaped inclined pressing surface on the front side of the wedge-shaped inclined flange connected to the head of the sleeve main body is in close contact with a wedge-shaped inclined pressure receiving surface on the rear side of the joint body. The sleeve body and the wedge-shaped inclined flange connected to the head thereof have a straight cylindrical pressing surface that presses against the outer peripheral surface of the sleeve body, and a pressure-receiving pressure provided on the rear side of the wedge-shaped inclined flange. Tightening that is shorter than the sleeve body, which is composed of a front suppressing flat surface that presses against a flat surface and a rear outwardly inclined surface, is done through an annular tube, and the tightening that is screwed onto the external thread of the joint body is done using a cap nut. By the outwardly inclined surface of the inner front side of
It is characterized in that it is fastened to the joint main body and the small diameter metal pipe, and the fastening is done by simply tightening the nut to the joint main body, and the tightening is performed through the intervening part. A sleeve body made of an elastic sealing material that is longer than the ring cylinder and a wedge-shaped inclined flange connected to its head are elastically tightened to the outer periphery of the thin metal tube and the wedge-shaped inclined pressure receiving surface of the joint body, and thereby, The purpose of this is to prevent leakage at the connecting portion and prevent crack damage to the sealing material and the outer periphery of the small diameter metal tube.

Conventionally, in this type of connection structure for small diameter metal tubes, a stepped fitting hole is provided on the inner periphery of the opening edge on one side of the through hole provided in the axis of the metal joint body. One end edge of a small diameter metal tube is tightly fitted into the stepped fitting hole, and an inclined receiving surface that connects to the outer peripheral surface of the small diameter metal tube and the edge of the stepped fitting hole in the joint body,
A metal annular seal member having an abacus bead shape in cross section is known to be tightened by screwing a cap nut onto a joint body.

In this conventional structure, the surface of the metal annular seal member is brought into direct pressure contact with the outer circumferential surface of the metal tube, so not only is it impossible to tighten the cap nut with a strong force, but also , they have poor leak-proof properties, and also have the disadvantage that due to mutual contact between these metals, the outer circumferential surface of the small diameter metal tube may be cracked and damaged by the peripheries of both side ends of the sealing member due to engine or mechanical vibrations.

In addition, conventionally, in a pipe joint that can adjust the expansion and contraction of the pipe length, (a) a coupling pipe that has a male thread on its outer circumferential surface and has an insertion hole in at least one end into which a pipe to be coupled can be inserted; (b)
a seal ring made of an elastic body, which has a truncated conical shape and has an insertion hole through which the pipe to be coupled can be coaxially inserted, and whose circumferential end surface corresponding to the bottom of the conical shape can come into close contact with the circumferential end surface of the insertion hole at the end of the coupled tube; (C) a cap nut having an insertion hole in the bag portion through which the pipe to be coupled can be coaxially inserted, and which can be screwed onto a male thread on the outer circumferential surface of the coupling pipe; and (d) the cap nut and a seal ring. It has an insertion hole that allows the pipe to be coupled to be inserted coaxially with the cap nut, and the peripheral end surface on the seal ring side can be brought into close contact with the conical surface of the seal ring, so that it can follow the movement of the cap nut in the axial direction. A hard annular fastener that is movable and rotatably locked in a cap nut, or a pipe joint that can adjust the expansion and contraction of the pipe length, (a) having a male thread on the outer circumferential surface; (b)
A sealing ring made of an elastic material, which has a truncated conical shape and has an insertion hole through which the pipe to be coupled can be inserted coaxially, and whose circumferential end surface corresponding to the bottom of the conical shape can come into close contact with the circumferential end surface of the insertion hole at the end of the coupled tube. (c) a cap nut having an insertion hole in the bag portion through which the pipe to be coupled can be coaxially inserted, and which can be screwed onto a male thread on the outer circumferential surface of the coupling pipe; and (d) a cap nut and a seal. It has an insertion hole that is interposed between the ring and the pipe to be coupled coaxially with the cap nut, and the circumferential end surface on the seal ring side matches the conical surface of the seal ring, and its diameter expands and contracts elastically by external force. A hard ring-shaped fastener is known, and furthermore, as a connection structure for a small diameter metal pipe, the end edge of the small diameter metal pipe is inserted into a communicating hole in the inner core of the base body. This is done by attaching an elastic filling cone made of rubber, synthetic resin, etc., fitted to the outer circumference of the end edge of the thin metal tube, to the inwardly inclined seat circumferential surface provided inside the opening edge of the communication hole of the base body. The outer tapered inclined peripheral surface of the annulus is anastomoses connected,
A bonded conical ring made of a hard material such as copper, lead, tin, or aluminum and having a flat end facing the outer flat surface of the elastic filling conical ring is attached to the end edge of the small diameter metal tube. The tapered inclined surface on the outer periphery of the connecting conical ring portion is screwed to the outside of the opening edge of the communicating hole of the base body, and the tightening is strongly tightened to the inclined inner circumferential surface of the inner bottom of the nut. Those that are also known are conventionally known.

However, these conventional tube joint structures have a drawback in that they are insufficiently capable of preventing leakage at the connecting portion.

Compared to these conventional structures, the invention of this application eliminates the drawbacks of these conventional structures, and the invention of this application eliminates the drawbacks of these conventional structures.
For example, the tightening is simply done by tightening the nut onto the joint body, and the tightening is done through the intermediate part, and the tightening is done by using the sleeve body made of an elastic sealing material that is longer than the ring cylinder and the wedge-shaped slope connected to the head of the sleeve body. The flange is elastically tightened to the outer periphery of the small diameter metal tube and the wedge-shaped inclined pressure receiving surface of the joint body, thereby preventing leakage at the connection part and preventing crack damage to the sealing member and the outer periphery of the small diameter metal tube. It is very useful because it can be prevented.

The invention of this application will now be explained with reference to the drawings.

1 to 3 show an embodiment of the invention of the present application, in which the inner periphery of the opening edge on one side of a through hole 2 provided in the axis of a joint body 1 made of metal or the like is shown. A straight cylindrical fitting step hole 3 is provided in the straight cylindrical fitting step hole 3, and a thin metal tube 4 is inserted into the straight cylindrical fitting step hole 3.
One end edge 4' is tightly fitted, and a sleeve main body 6 made of an elastic sealing material such as synthetic resin or rubber and having a wedge-shaped inclined flange 5 at the head is tightly fitted into the outer peripheral surface 1 of the small diameter metal tube 4. The wedge-shaped inclined pressing surface 7 of the wedge-shaped inclined flange edge 5 forms a wedge-shaped inclined receiving surface 1 which is connected to the mouth edge 8 of the straight cylindrical fitting stepped hole 3 of the joint body 1.
At the same time, the screws 11 on the outside of the joint body 1 are tightened against the rear pressure-receiving flat surface 10 of the wedge-shaped inclined flange 5 of the head, and on the inside inclined surface 13 of the cap nut 12. A pressing flat surface 16 of a wedge-shaped inclined cylinder 15 having a pressing inclined surface 14 is pressed.

FIG. 4 shows a conventional connection structure for this kind of small-diameter metal tube, in which a stepped bottom tube is formed on the inner periphery of the opening edge on one side of the through hole 2 provided in the axis of the metal joint body 1. A fitting hole 3 is provided, and one end edge 4' of the small diameter metal tube 4 is tightly fitted into the stepped fitting hole.
A metal annular sealing member 5' with an abacus bead shape is attached to the inclined receiving surface 9 connected to the mouth edge 8 of the stepped fitting hole 3, which is tightened with a cap nut 12 and screwed onto the joint body 111'. It can be tightened by doing this.

[Brief explanation of the drawing]

FIG. 1 is a front view of this invention, FIG. 2 is a cross-sectional view taken along the line II in FIG. 1, FIG. 3 is a cross-sectional view taken along the line ■--■ in FIG. In the drawings, the same reference numerals indicate the same or equivalent parts, 1 is the joint body, 2 is the through hole, 3 is the straight cylindrical fitting stepped hole, 4 is the thin metal tube, 4' is the front edge thereof, and 4'' is Outer peripheral surface, 5 is a wedge-shaped inclined flange edge, 5' is an abacus bead-shaped metal annular seal member, 6
1 is a sleeve body made of an elastic sealing material, 7 is a wedge-shaped inclined pressing surface of the wedge-shaped inclined flange edge 5, 8 is an opening edge of the straight cylindrical fitting step hole 3, 1
is a wedge-shaped inclined receiving surface, 10 is a flat back pressure receiving surface, 11, 11'
12 is a cap nut for tightening, 13 is an inner inclined surface thereof, 14 is another inclined surface, 15 is an annular cylinder for tightening, and 16 is a suppressing flat surface.

Claims (1)

[Scope of utility model registration request] A wedge-shaped inclined receiving surface is provided on the rear surface of the rear opening edge of the straight cylindrical fitting step hole provided at the rear opening edge of the shaft center through hole of the joint body made of metal, etc. The front end edge of a small diameter metal tube is tightly fitted into the step hole, and a relatively long sleeve body made of an elastic sealing material such as synthetic resin or rubber is tightly fitted onto the outer peripheral surface of the small diameter metal tube. The wedge-shaped inclined pressure surface on the front side of the wedge-shaped inclined flange connected to the head of the sleeve body is in close contact with the wedge-shaped inclined pressure receiving surface on the rear side of the joint body, and the sleeve body The wedge-shaped inclined flange connected to the head of this sleeve has a straight cylindrical pressing surface that presses against the outer peripheral surface of the sleeve body, and a front suppression surface that presses against the pressure-receiving flat surface provided on the rear side of the wedge-shaped slanted flange. The tightening part shorter than the sleeve body, which consists of a flat surface and a rear outwardly inclined surface, is tightened through the ring tube, and the tightening part screwed to the external thread of the joint body is attached to the outwardly inclined inner front side of the cap nut. A joint structure for a small diameter metal pipe, characterized in that the joint body and the small diameter metal pipe are fastened to the joint body and the small diameter metal pipe by a surface.