JPH0658296U - Pipe fitting - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a pipe joint in which buckling of the pipe body, which is likely to occur near the connecting portion with the pipe joint when the pipe body is bent, is prevented. [Structure] A sleeve 30 is externally fitted to one end of a tubular body T fitted into an insert portion 11 of a joint body 10, and the sleeve 30 is contracted and deformed by tightening a union nut 20 to form a tubular body between the tubular body and the insert portion 11. This is a pipe joint of a type that holds T, and the sleeve 30 has a length protruding from the union nut 20, and a through hole 34 is provided in the protruding portion, so that the protruding portion can be curved. [Effect] Since the vicinity of the connecting portion of the pipe body is held by the sleeve, the pipe body does not flatten when bent even without using a dedicated member.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pipe joint which is applied to a flexible pipe body mainly made of a polymer material such as a tube or a hose and which prevents the buckling of the pipe body in the vicinity of a connection portion.

[0002]

[Prior art]

 As a conventional pipe joint for the above-mentioned flexible pipe body, as known from JIS B8331 “Pneumatic pipe joint (for flexible pipe)”, there is known a pipe joint body composed of a joint body, a union nut and a sleeve. Therefore, it is widely used in piping systems other than the pneumatic circuit, in addition to the connection between various devices and the pipe body in the pneumatic circuit. However, when pipes made of relatively hard synthetic resin such as nylon or fluororesin are connected to this type of pipe joint and the pipes are bent, the pipe walls of those pipes are inserted into the union pipe. The phenomenon of flattening while folding near the mouth (called buckling or kink) is likely to occur. For this reason, under the expected operating conditions, a coiled metal wire of a specified length should be placed close to the pipe joint and then externally attached to the pipe body, or one end has an integral part for the pipe joint. A coil-shaped body made of a synthetic resin formed in the above is extrapolated (Japanese Utility Model Laid-Open No. 3-93694).

[0003]

[Problems to be solved by the device]

 However, either method requires a separate buckling prevention member, and the buckling prevention member must be attached separately from the connection work between the pipe body and the pipe joint. The problem with this type of pipe fitting is that a large increase in piping costs is inevitable.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to provide a pipe joint capable of preventing buckling of a pipe body in the vicinity of a connection portion without increasing piping cost. To do.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, according to the present invention, a sleeve is externally fitted to one end of a tubular body fitted in an insert portion of a joint body, and a diameter of the sleeve is reduced by tightening a union nut screwed to the joint body. In a pipe joint in which a tubular body is sandwiched between the sleeve and the insert portion by being deformed, the other end of the sleeve projects from the tubular body insertion port of the union nut in a tubular body connected state, and the peripheral wall of the projecting portion can be curved. It is characterized by being integrally molded with synthetic resin.

In order to make the protruding portion of the sleeve bendable, for example, a through hole may be provided in some places on the peripheral wall, a bellows shape may be formed, or the protruding portion may be made thinner than other portions. Good, but not necessarily limited to this. In this case, it is convenient to prevent the buckling of the pipe by gradually increasing the bendability from the base of the protruding portion closest to the joint body toward the end.

[0007]

[Action]

 When the pipe is connected to the pipe joint configured as described above, the portion near the connecting portion of the pipe is surrounded by the synthetic resin sleeve protruding from the pipe insertion opening of the union nut. Since the protruding part of this sleeve is bendable, when the pipe is bent at a position close to the connection with the pipe joint, the protruding part of the sleeve bends while holding the pipe while following it. Therefore, the pipe body does not buckle.

[0008]

【Example】

 Next, the pipe joint of the present invention will be described in more detail with reference to the drawings, but of course the present invention is not limited to the embodiments, and modifications can be made within the technical idea of the present invention.

FIG. 1 is a partial vertical sectional view showing an embodiment of a pipe joint according to the present invention. The illustrated pipe joint 1 is composed of a joint body 10, a union nut 20, and a sleeve 30. In the embodiment, the joint body 10 is provided with an insert portion 11 that fits inside one end of the tubular body T to be connected, and the receiving groove of the tubular body T is provided on the outer peripheral side of the insert portion 11. An outer cylinder portion 13 is provided with an annular space 12 between the outer cylinder portion 13 and the outer space 13 being separated. The tip of the outer tube portion 13 is located axially inward (left side in FIG. 1) with respect to the tip of the insert portion 11, and the tip portion has a taper portion 14 whose diameter decreases in the tube insertion direction. Is formed, and the external thread portion 15 is provided on the outer peripheral surface.

The union nut 20 has a tubular body insertion port 21 on one end side, and has a female screw portion 22 screwed to a male screw portion 15 provided on the outer cylinder portion 13 of the joint body 10 on the other end side. Further, between the female screw portion 22 and the tubular body insertion port 21, a taper portion that faces the taper portion 14 formed at the distal end portion of the outer tubular portion 13 and engages via a sleeve 30 to be described later. Equipped with 23.

The sleeve 30 is a tubular body made of synthetic resin such as polyamide, polyester, polyvinyl chloride, etc., and its inner diameter is slightly larger than the outer diameter of the tubular body T to be connected. It is fitted on the end of T. The distal end portion of the sleeve 30 in the tube insertion direction is formed to have a larger diameter than the other, and the tapered portion 14 of the joint body 10 and the tapered portion 23 of the union nut 20 are connected to both sides of the large diameter portion 31 at the time of connection. Are provided with tapered portions 32 and 33, respectively. The length of the sleeve 30 is set so that the rear end of the sleeve 30 projects from the tubular body insertion opening 21 of the union nut 20 when the tubular body T is completely connected. A plurality of through holes 34 are provided at predetermined intervals in the circumferential direction and the axial direction. In this case, the through holes 34 have the same size in the circumferential direction, but are formed so as to become larger toward the rear end side of the sleeve 30 in the axial direction, so that the protruding portion of the sleeve 30 is unreasonable. It is designed to bend without.

Next, a usage mode of the pipe joint 1 according to the present invention will be described. First, the union nut 20 and the sleeve 30 are inserted into the tubular body T in this order, and the tubular body T is inserted into the tubular body receiving groove 12 of the joint body 10. Then, when the female threaded portion 22 of the union nut 20 is screwed onto the male threaded portion 15 of the joint body 10 and tightened, the sleeve 30 is pushed toward the joint body 10 side by the taper portion 23 of the union nut 20, and the tip end side of the sleeve 30. The tapered portion 32 comes into contact with the tapered portion 14 formed at the tip of the outer tubular portion 13 of the joint body 10. When the sleeve 30 is further tightened, the tapered portions 32 and 33 of the large-diameter portion 31 are pinched by the tapered portion 14 of the joint body 10 and the tapered portion 23 of the union nut 20 from both sides in the axial direction. Force acts on the large-diameter portion 31 to reduce its diameter and press the tubular body T from the outer peripheral surface. The inserted tubular body T is fixed by being sandwiched between the sleeve 30 and the insert portion 11 of the joint body 10.

In the pipe body T connected to the pipe joint 1 in this manner, a portion near the pipe body insertion opening 21 of the union nut 20 is surrounded by a synthetic resin sleeve 30 protruding from the rear end surface of the union nut 20. To be done. The protruding portion of the sleeve 30 is reasonably curved by a plurality of through holes 34 provided in the peripheral wall thereof. Therefore, when the pipe body T is bent at a position close to the connection portion with the pipe joint 1, the protruding portion of the sleeve 30 bends while hugging the pipe body T and following the curve. The buckling of T can be completely prevented.

FIGS. 2 and 3 are different examples of sleeves that can be used in the pipe joint according to the present invention. In the sleeve 40 shown in FIG. 2, a rectangular through hole 41 elongated in the axial direction is provided. It has a structure in which the peripheral wall of the rear end portion protruding from the union nut is provided at equal intervals in the circumferential direction. The sleeve 50 shown in FIG. 3 is provided with circumferential grooves 51 at equal intervals on the outer peripheral surface of the peripheral wall of the rear end side portion, and further has a long hole-shaped through hole 52 and a notch 53 which are long in the axial direction. Has a structure. Although not shown, a similar effect can be obtained even if the peripheral wall of the rear end side portion of the sleeve is formed into a bellows shape, or the wall thickness of the peripheral wall is gradually reduced toward the rear end, and it is possible to bend. The shape is not limited to this.

[0015]

[Effect of device]

 As described above, in the pipe joint according to the present invention, the rear end side of the sleeve that holds the inserted pipe body with the insert portion of the joint body is projected from the union nut, and the through wall is provided in the peripheral wall of the protruding portion. Since the protruding portion of the sleeve can be curved by such means, a dedicated buckling prevention member as in the past is not required, and it is possible to obtain a practically excellent effect that the buckling of the pipe body can be prevented extremely economically.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view showing a state in which pipes are connected in an embodiment of a pipe joint according to the present invention.

FIG. 2 is a vertical cross-sectional view showing another embodiment of the sleeve used in the pipe joint according to the present invention.

FIG. 3 is a partial vertical sectional view showing a further different embodiment of the sleeve used in the pipe joint according to the present invention.

[Explanation of symbols]

 10 Joint Main Body 11 Insert Part 13 Outer Cylinder Part 14, 23, 32, 33 Tapered Part 20 Union Nut 21 Tubular Body Insertion Port 30, 40, 50 Sleeve 34, 41, 52 Through Hole

Claims (1)

[Scope of utility model registration request] 1. A sleeve is externally fitted to one end of a tubular body fitted in an insert portion of a joint body, and the sleeve is contracted and deformed by tightening a union nut screwed to the joint body, and a space between the sleeve and the insert portion. In the pipe joint for sandwiching the pipe body with the sleeve, the other end of the sleeve protrudes from the pipe body insertion port of the union nut in a pipe body connected state, and the peripheral wall of the protruding portion is integrally molded with a bendable synthetic resin. A pipe joint characterized by: