JPH06174156A - Flareless tube fitting - Google Patents

Abstract

PURPOSE:To achieve emergency reuse by interposing a union between a tube fitting main unit and a tightening nut. CONSTITUTION:A large bore opening part of a union 8, providing a ring-shaped edge 5 in a left side large bore opening part internal peripheral surface and also a circular cone internal surface 6 in a right side small bore opening part internal peripheral surface, is screwed to a circular cone end face 1 of a tube fitting main unit 3, to press contact seal between the circular cone end face 1 and the ring-shaped edge 5, and a soft metal-made ring 18 is brought into contact with the circular cone internal surface 6 or the union. A tightening nut 14, provided with a circular cone internal surface 13 in the internal surface, is screwed from rightward of the soft metal-made ring 18 to contract its diameter, and a pipe 30, arranged in the inside of the soft metal-made ring, is press interposed and fixedly sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reusable flareless pipe joint mainly used for a refrigerant pipe such as an air conditioner.

[0002]

2. Description of the Related Art Conventionally, various flareless pipe joints have been invented. The "metal pipe joint" of Japanese Examined Patent Publication No. 57-48717 is a typical one, which has a hole for inserting a pipe in the center, a ring made of a soft metal with a substantially spherical outer periphery, and a taper on the inner peripheral surface of the tip. It is sandwiched between the formed joint body and the tightening nut that has a taper on the inner peripheral surface of the inner part facing the taper, and the tightening nut is attached to the joint body with the pipe inserted through the hole of the soft metal ring. By screwing in, the diameter of the soft metal ring is reduced by the both tapered surfaces, the pipe is pinched, and the seal is fixed.

However, in the above means, since the pipe is clamped and fixed by reducing the diameter of the soft metal ring, when the pipe material is a soft pipe such as a copper pipe or an aluminum pipe, the pipe itself is used. Also, the diameter is reduced and deformed inward, and the pressure contact becomes insufficient, so that the bonding force and the sealing property are deteriorated.

As a means for solving the above-mentioned problems, Shokai 6
There is a "flareless pipe joint" of 4-55393. As shown in FIG. 4, a sleeve 32 made of a hard material having a collar 31 at one end is interposed on the inner surface of the pipe 30, and the inner peripheral end of the pipe 30 is located on the outer peripheral surface of the pipe 30 located on the outer periphery of the sleeve. A thick portion 37 having a tapered surface 36 that matches the inclination of the conical end surface 1 of the joint body 3, an intermediate thin portion 38 having a concave inner side, and an outer surface having a conical cam surface 44 of the nut member 43.
A metal pipe 42 formed of a locking portion 41 having a tapered surface 39 corresponding to the inclination of and having a plurality of annular claws 40 inside
The conical end face 1 of the joint body 3 and the nut member 4
The conical cam surface 44 at the inner part of 3 seals the pipe 30 without distorting the pipe 30 by pinching the taper surface 36 of the pipe 42, so that the annular claw 40 on the inner peripheral surface of the pipe is difficult to be inserted into the pipe surface for sealing. It is the one to combine.

[0005]

However, in any of the above cases, the pipe surface is tightened by utilizing the deformation of the soft metal ring or the metal barrel by screwing the tightening nut into the joint body. Once tightened, the ring and barrel cannot be reused. However, in reality, there are cases where it is necessary to move the air conditioner (air conditioner) due to installation mistakes, moving, changing the installation location, or the like. In such a case, if the nut is removed from the joint body, the pipe will come off from the joint body, but the plastically deformed metal ring or barrel will not come off from the pipe. Then, since the reliable sealing property cannot be obtained even if this pipe is reused, the pipe is actually cut outside the sealing part or the part where the sleeve is fitted (not shown) and prepared separately separately. It had to be tightened with a new soft metal ring or barrel and sleeve.

However, the structure of the joint portion varies depending on the air conditioner manufacturer, and it is not always the case that nuts and metal rings (cylinders) that fit are prepared as spares. Therefore, I thought that when reconnecting the pipe, the tip of the cut pipe was connected by the conventional flare pipe method. In the "flareless pipe joint" method, the conical angle of the conical end surface 1 at the tip of the joint body and the conical angle of the conical cam surface 44 at the inner end of the nut member are different in the "flareless pipe joint" method. Was not applicable.

[0007]

According to the present invention, a soft metal ring whose outer peripheral edges are arcuate or tapered is used to fix the pipe at a reduced diameter, and the most reliable conventional seal is used to seal the joint body. A metal seal is adopted by pressure contact of the ring-shaped edge, and a union is interposed between the joint body and the tightening nut.

That is, one of the basic constitutions of the present invention is that the conical end surface 1 of the joint body 3 is provided with the ring-shaped edge 5 on the inner peripheral surface of the large diameter opening on the left side and on the inner peripheral surface of the small diameter opening on the right side. The large diameter opening of the union 8 provided with the conical inner surface 6 is screwed in to seal the conical end surface 1 and the ring-shaped edge 5 by pressure, and the inner surface 6 of the union inner cone 6 is provided with a soft metal ring
And a tightening nut 14 having a conical inner surface 13 on its inner surface is screwed into the soft metal ring 18 from the right side.
The diameter of the pipe is reduced, and the pipe 30 arranged inside the soft metal ring is pinched and fixed by sealing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention, as shown in FIG. 1, is a joint body 3 having a conical end surface 1 on the outer periphery of the tip and a screw 2 on the outer periphery of the rear end thereof.
And a female thread 4 which is screwed with the male thread 2 on the inner peripheral surface of one large diameter opening, a ring-shaped edge 5 in contact with the conical end surface 1 on the inner side thereof, and a cone on the inner peripheral surface of the other small diameter opening. The inner surface 6 is provided with a union 8 having an external thread 7 having the same diameter as the external thread 2 on its outer peripheral portion, and an internal thread 11 that is screwed onto the external thread 7 of the union is provided on one internal peripheral surface of the union 8. A ring-shaped tightening nut 14 which is provided with a pipe insertion hole 12 at its end, and has a conical inner surface 13 in the same direction and angle as the conical end surface 1 of the joint body 3 at the inner peripheral edge of the pipe insertion hole.
And a pipe insertion hole 15 at the center, and an arc surface 1 having an angle smaller than the conical inner surface 6 of the union inner peripheral portion at one end of the outer peripheral edge.
6 and a soft metal ring 18 having a conical surface 17 at the same angle as the conical inner surface 13 at the inner peripheral edge of the tightening nut at the other end, which are assembled in advance as a set.

According to the present invention, the union in the set state is
The conical end face 1 and the ring-shaped edge 5 are bited into the joint body 3 by screwing into the joint body 3 to seal the pipe 3
Inserting 0 from the outside into the pipe insertion holes 12 and 15 at the center of the nut and the soft metal ring 18 and screwing the tightening nut 14 into the union, the soft metal ring 18 is reduced in diameter and the pipe 30 is pinched and sealed. It is something that is fixed.

Reference numeral 19 in the figure is a sleeve 19 made of a hard metal, having an outer diameter that can be inserted into the pipe 30, and a cut step 20 is formed at one end thereof. The inner collar 9 formed at the center of the inner peripheral surface of the union 8 is fitted into the inner side of the union 8 and the tip of the sleeve 19 is bent outward as shown to form the caulked portion 21.
Can be fixed to the union 8.

When this sleeve 19 is used, the pipe 30 is inserted between the outer peripheral portion of the sleeve and the inner peripheral portion 10 of the small diameter opening of the union 8, and the seal is fixed from the outside by reducing the diameter of the soft metal ring 18. Will be done. Therefore, the sleeve 19 need only be in a predetermined position when the pipe is fixed, and it is not always necessary to perform the crimping fixing with the inside of the union. When the sleeve 19 is prepared as a set together with the ring 18 and the tightening nut 14, it is convenient because each member is not separated.

The soft metal ring 18 shown in FIG. 2 has a thin ring-shaped projecting piece 24 having an inner diameter D1 smaller than the outer diameter D2 of the pipe 30 at the tip of the arc surface 16.
Since the ring-shaped projecting piece 24 bites on the outer peripheral surface of the pipe 30 when the pipe 30 is inserted into the pipe joint, the pipe is temporarily fixed. Therefore, when the tightening nut 14 is tightened, it is pulled to the pipe 30 for convenience of piping work. Even if a force (a force acting in the direction in which the pipe comes out of the pipe joint) is applied, the pipe 30 does not displace and the seal can be fixed to the soft metal ring 18 in the normal position to improve the reliability of the seal and the workability. It also improves.

[0014]

Since the present invention has the above-mentioned structure, the operation for tightening and fixing is simple and reliable. And
If you make a mistake in fitting the fittings or move the air conditioner,
The pipe 30 is cut on the outside of the tightening nut 14, and the tip portion of the pipe is flared by a conventional method.
As described above, the flare portion of the pipe can be sandwiched between the conical inner surface 13 of the tightening nut 14 and the conical end surface 1 of the joint body to be fixed by sealing. Therefore, even if there is no spare union, soft metal ring, sleeve, etc., it is possible to make a temporary pipe connection.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of an example of the present invention.

FIG. 2 is an enlarged vertical side view of the vicinity of the ring before tightening the nut.

FIG. 3 is a vertical cross-sectional side view in a state of being connected by a flare method.

FIG. 4 is a semi-longitudinal side view of a conventional product.

[Explanation of symbols]

1 Conical end face. 3 Joint body.
5 Ring edge. 6 Inner surface of cone. 8 Union. 13 Inner surface of cone. 14 Tightening nut. 18 Soft metal ring. 19 sleeves.
20 Inner end face of cone. 24 Ring-shaped protruding piece.
30 pipes.

Claims (4)

[Claims] 1. A large diameter opening of a union 8 in which a conical end surface 1 of a joint body 3 is provided with a ring-shaped edge 5 on the inner peripheral surface of the left large diameter opening and a conical inner surface 6 is provided on the inner peripheral surface of the right small diameter opening. The part is screwed in, and the conical end face 1 and the ring-shaped edge 5 are pressure-contacted and sealed, and the soft metal ring 18 is brought into contact with the conical inner surface 6 of the union.
A flareless pipe joint characterized in that a tightening nut 14 provided with No. 3 is screwed in, the diameter of the soft metal ring 18 is reduced, and a pipe 30 arranged inside the soft metal ring 18 is pinched and seal-fixed. 2. The flareless pipe joint according to claim 1, wherein a sleeve 19 made of hard metal is provided on the inner circumference of the pipe 30. 3. The flareless pipe joint according to claim 2, wherein one end of a sleeve 19 made of hard metal is fixed to the inner surface of the center of the union 8. 4. The flareless pipe joint according to claim 3, wherein the soft metal ring 18 is provided at the tip of the arc surface 16.
A flareless pipe joint, characterized in that a thin ring-shaped projecting piece (24) having an inner diameter dimension (D1) smaller than the outer diameter dimension (D2) of the pipe (30) is provided.