JPH0517519Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a metal flexible tube that can be easily connected to a fitting at its end to prevent fluid from leaking.

[Conventional technology]

Conventionally, metal composite flexible tubes are made by fitting the end of a metal corrugated tube into one end of a fitting, and welding the corrugated tube end to the fitting to form a sealed integral body. In order to prevent directional elongation, a wire braided tube is coated on the outer periphery of the corrugated tube as a covering material if necessary, and the end of this wire braided tube is also welded to the fitting.

[The problem that the idea attempts to solve]

For this reason, welding of the corrugated pipe and the joint fittings takes time and effort, and the cost of the product is high. In addition, the heat generated during welding affects the material of the corrugated pipe, etc. The purpose of the present invention is to omit the welding process and to connect fittings in a sealed manner.

[Means to solve the problem]

A fitting is fitted into the end of a metal corrugated pipe via an O-ring, a back-up spring is fitted onto the outer periphery of the end of the corrugated pipe, and this ring is held together with a blade that covers the outer periphery of the corrugated pipe. A fixing fitting is fitted to the outer periphery of the corrugated tube, and a fixing fitting is fitted onto the outer periphery of the corrugated tube, and the fitting is crimped to fix the corrugated pipe and the fitting in a watertight manner.

〔Example〕

The composite flexible tube of the present invention will be explained below based on the drawings.

In the figure, 1 is stainless steel, depending on the application.
A corrugated metal tube made of copper, aluminum, etc. selectively; the corrugated metal tube 1 has the required length, diameter, and wall thickness, and its tip 11 is pre-extended a little more than the corrugated tube. It is shaped like a straight tube.

Reference numeral 2 denotes a cylindrical inner tube that is fitted over the entire length of the inner peripheral surface of the corrugated metal tube 1, and is made of a synthetic resin tube or the like.
A material with desired pressure resistance and tension resistance is selected and used to prevent the turbulence of the fluid flowing therein and to ensure smooth flow down.

Reference numeral 3 denotes a joint fitting, which has a female type with a cap nut 5 and a bolt-like male type as shown in the figure, and is selected and used as appropriate. The grooves 35 and 36 are shaped like short pipes and have a hole 34 of a desired diameter, which is inserted into the tip 11 of which the fluid flows. In addition, the grooves for fitting each O-ring shall have a required interval, and the locking groove 32 of the fixing metal fitting 4 is placed on the outer end side of the groove 35, and the locking groove 32 of the fixing metal fitting 4 is placed on the inner end side of the groove 36. A groove 37 into which the tip of the intubation tube 2 fits is formed, and the tip of the fitting 3 is expanded into a morning glory shape.
The locking piece 31 is integrally formed so as to lock with the inner locking surface 51 of the cap nut 5.

Reference numeral 6 denotes a back-up spring that is fitted around the outer periphery of a substantially straight part of the corrugated metal pipe 1 and is interposed between the straight part of the corrugated pipe 1 and the blade 7.
It is made of metal such as copper, and when the fixing metal fitting 4 is crimped and fixed from the outer circumference of the blade 7 provided over the entire length of the metal corrugated pipe 1 to protect the pipe with this back-up spring 6, the blade is strongly pressed. This protects the straight pipe section of the corrugated metal pipe from damage.

This braid 7 is made of thin metal wires such as stainless steel or copper, knitted into a cylindrical shape, and by fitting and covering the outer periphery of the corrugated tube 1, it prevents the corrugated tube 1 from elongating due to the applied pressure. , and protect its outer surface.

Further, the outer circumferential surface of the blade 7 is sometimes fitted with a covering tube (not shown) made of synthetic resin or rubber to protect the blade 7 from rotting and dirt caused by chemicals, oil, etc.

Reference numeral 4 denotes a fixing metal fitting, and the fixing metal fitting 4 is shaped like a metal pipe, and has a shape in which a small-diameter fixing cylinder part 41 is protruded from the tip of a large-diameter holding cylinder part 42 on the base end side. The fixed cylinder part 41 is fitted into the locking groove 32 to be integrated with the joint fitting 3, and the holding cylinder part 4 is integrated with the joint fitting 3.
The inner diameter of 2 is adapted to fit on the outer periphery of a braid 7 that covers the corrugated tube 1.

Reference numeral 5 denotes a cap nut, which is normally used for joining flexible tubes, and this cap nut 5 is rotatably locked to the locking piece 31 of the joint fitting 3.

Next, the order of assembling the parts configured as described above will be explained. A back-up spring 6 is fitted onto the outer periphery of the straight pipe portion at the end of the metal corrugated pipe 1 into which the inner tube 2 has been fitted in advance. The outer periphery of this backup spring 6 is covered with a blade 7 together with the outer periphery of the corrugated metal tube. The outer peripheral surface of the blade 7 may be covered with a covering tube.

At this time, the end of the metal corrugated tube 1 has been stretched in advance into a straight tube shape, and is easily fitted onto the joint fitting 3. At this time, the end of the inner tube 2 is fitted into the groove 37 of the fitting 3. Next, the fixing fitting 4 is fitted onto the outer periphery of the corrugated tube end of the joint fitting 3 so as to fit onto the outer periphery of the back-up spring and the blade, and the holding cylinder part 42 and the fixing cylinder part 41 of the fixing fitting are fitted. Apply crimping or other squeeze processing to the outer periphery as shown in the figure. At this time, the O-rings 8, 8 are in the groove 35,
36, in other words, a part of the O-ring is deformed to seal the space between the coupling fitting 3 and the straight pipe part 11 of the corrugated pipe, and also to seal the annular corrugated pipe end, the inner tube, and the holding cylinder part. are crimped and held together to become one piece.

When the fixing fitting 4 is crimped, the back-up spring 6 made of aluminum or copper is interposed between the blade 7 and the metal corrugated tube 1, so that the corrugated tube 1 is securely crimped and fixed without damaging it.

Next, insert the cap nut 5 into the end of the joint, expand the end of the joint, and tighten the cap nut 5 as shown in FIG.
is attached to the joint fitting 3. Note that this cap nut 5 can also be fitted into the joint fitting 3 in advance.

[Effect of idea]

According to the present invention, a back-up spring is fitted around the outer periphery of the end of a metal corrugated pipe, and this ring is also covered with a blade that covers the outer periphery of the corrugated pipe.
A fixing fitting is fitted to this outer periphery, the outer periphery of this fixing fitting is squeezed, and the straight pipe part of the corrugated pipe and the fitting fitting are fixedly engaged with each other via an O-ring by the holding cylinder part of the fixing fitting. This makes it possible to easily fix corrugated pipes in a watertight manner without welding, reduce costs by reducing the number of parts, and furthermore avoid the effects of heat on the material, improving accuracy. In addition, since a back-up spring is interposed between the metal corrugated tube and the blade at the crimping part of the metal corrugated tube's fixing fitting, the metal corrugated tube and the braid can be easily crimped when the fixing fitting is crimped. It protects the parts and allows for highly accurate joints.

[Brief explanation of drawings]

The drawing is a front view in section of the upper half. 1 is a metal corrugated tube, 2 is an inner tube, 3 is a fitting, 31 is a locking piece, 32, 35, 36, 37 are grooves, 4 is a fixing metal fitting, 41 is a fixed cylinder part, 42 is a holding cylinder part , 5 is Bucknut, 6 is Buckup Spring,
7 is the blade, 8 is the O-ring.

Claims (1)

[Scope of utility model registration request] A fitting is fitted into the end of a metal corrugated pipe via an O-ring, a back-up spring is fitted onto the outer periphery of the end of the corrugated pipe, and this ring is held together with a blade that covers the outer periphery of the corrugated pipe. A composite flexible tube is formed by covering the pipe, fitting a fixing fitting around the outer periphery, and crimping the fixing fitting to securely engage and fix the corrugated tube and the fitting fitting in a watertight manner.