JP3438134B2 - Connection maintaining device in threaded pipe joint - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw member rotatably locked at least at one end of a pipe and the other screw member to be screwed with the screw member. The present invention relates to a device for reliably maintaining the connection between the pair of pipes in a pipe joint for connecting the pair of pipes with a screw member. 2. Description of the Related Art Conventionally, for example, a cap nut is rotatably engaged with one end of a pair of pipe ends each having a flange at each end, and an annular screw is rotatably engaged with the other end. Nut and screw loose joints for tightly connecting a pair of pipes with a gasket therebetween by screwing are widely used. [0003] However, in the above-mentioned conventional pipe joints, after tightening and connecting, each part slightly expands and contracts due to a change in operating temperature, and the threaded part is loosened due to vibration, impact, or the like, or the gasket deteriorates over time, resulting in poor connection. When this occurs, the cap nut and the annular screw are re-tightened manually by an operator, but in a plant equipped with a large number of pipe joints, the re-tightening work requires a great deal of labor and time. SUMMARY OF THE INVENTION [0004] The present invention is intended to prevent connection failure when a connection failure occurs due to expansion and contraction of each part, loosening of a threaded portion, deterioration of a gasket, and the like, and a strong connection. The challenge is to maintain [0005] As means for achieving the above object, the present invention provides a screw member rotatably locked to at least one end of one tube, and a screw member for the screw member. In a pipe joint for connecting a pair of pipes with the other screwing member, a wire whose one end is connected to the outer circumferential surface of the one screwing member is screwed to the outer circumferential surface of both screwing members. A spring member that winds in the same direction as the forward rotation direction and connects the other end of the wire to the outer peripheral surface of the other screw member, and resiliently engages the two screw members with the wire in the screw rotation direction. Is proposed, a connection maintaining device in a threaded pipe joint is connected. [0006] In the above-mentioned "pipe joint" of the present invention, a cap nut is rotatably engaged with one end of a pair of pipes having a flange at each end, and an annular screw is mounted at the other end of the pipe. The nuts and screws are screwed together to connect the above-mentioned pair of pipes, and the cap nuts are rotatably engaged with the respective pipe ends of the pair of pipes whose ends have been expanded. The two ends are screwed into threaded nipples, respectively, to connect the above-mentioned pair of pipes, a flange is fixed to one end of the pipe, and a cap nut is freely rotatably engaged with the other pipe end. A pipe joint for fixing the threaded nipple, screwing the cap nut and the nipple to connect the pair of pipes, and various other things are included. Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a perspective view of a pipe joint according to a first embodiment of the present invention, showing a pair of pipes (1) and (1) having flanges (2) and (2) at their ends, respectively. A cap nut (3) having an annular female thread (5) protruding from one side of a ring-shaped body (4) having a round hole is rotatably engaged with the end of (1), and the other pipe is provided. At the end of (1), an annular screw (6) formed by projecting an annular male screw portion (8) on one side surface of a ring-shaped main body (7) having a round hole is rotatably engaged, and these cap nuts are used. A pair of pipes (1) and (1) are connected by press-fitting the flanges (2) and (2) with a gasket (9) therebetween by screwing the (3) and the annular screw (6). Is what you do. (10), (10) is the cap nut (3)
In order to prevent corrosion occurring between the pipe and the pipe (1) and between the annular screw (6) and the pipe (1), a synthetic resin made of a synthetic resin such as ethylene tetrafluoride is interposed therebetween. It is a cylindrical electric insulating material. A bracket (11) protruding from the outer peripheral surface of one of the cap nuts (3) in the pipe joint as described above includes:
One end of a wire (12) having a length of about two turns on the outer peripheral surface of the cap nut (3) is connected, and the eyebolt (13) connected to the other end of the wire (12) is connected to the other annular screw. (6) is slidably inserted into a bracket (14) protruding from the outer peripheral surface, a spring (15) is wound around the insertion projection of the eyebolt (13), and a double nut ( 16) is screwed. (17), (1
7) is a spring receiving seat. The operation of the above example is as follows. First, the direction of screwing rotation of the cap nut (3) and the ring-shaped screw (6) (the direction of rotation of the threaded counterpart toward the side) is determined by the nut (3) and the screw (6). In the case of a right-handed screw, the rotation is clockwise. First, with the double nut (16) removed and the eyebolt (13) pulled out of the bracket (14), the cap nut (3) and the annular screw (6) are screwed together, and the flanges (2), (2) ) With gasket (9) sandwiched enough. Next, a wire (12) having one end connected to the bracket (11) is wound clockwise around the outer periphery of the cap nut (3) and the annular screw (6), and the eyebolt (13) at the other end is connected to the other end. The spring (15), the receiving seat (17), (1)
7) and the double nut (16) are mounted, and in this state, the double nut (16) is turned to compress the spring (15), whereby the elasticity of the compression spring (15) is applied to the wire (12). A tensile force is applied by the restoring force, and an elastic tensile force in the screw rotation direction is constantly applied to the cap nut (3) and the annular screw (6) via the wire (12). Therefore, if a failure occurs in the connection, the cap nut (3) and the annular screw (6) are automatically retightened by the elastic tensile force of the wire (12), thereby preventing the failure from occurring. At the same time, the above-mentioned elastic pulling force is always applied in the screwing direction of the cap nut (3) and the annular screw (6), so that the two screws (1) and (2) are screwed together.
The connection of (1) will be maintained firmly. Preferably, a series of spiral wire guide grooves (18) extending from the brackets (11) to (14) are formed on the hexagonal outer peripheral surfaces of the cap nut (3) and the annular screw (6). (18), and a wire (1) is provided in the guide groove.
2) is engaged to make the sliding of the wire (12) smooth. In another embodiment of the present invention, a pair of tubes are connected by rotatably locking cap nuts at each end of a pair of pipes, and screwing both cap nuts into nipples with thread at both ends. When the present invention is applied to a type of pipe joint, the bracket (11), (14), the wire (12), and the eyebolt of the above example are respectively provided between one cap nut and the nipple and between the other cap nut and the nipple. (13), spring (1
5) and the same structure as the double nut (16) is arranged, in which case the wire is wound right-handed with the screwing of one cap nut and the nipple as the right screw, and the screwing of the other cap nut and the nipple is performed. Preferably, the wire is left-handed as a left-hand thread. According to the apparatus for maintaining connection in a threaded pipe joint according to the present invention, after tightening connection, each part slightly expands and contracts due to a change in operating temperature, and the threaded part is loosened due to vibration and shock, or If the gasket deteriorates over time and a failure occurs in the connection, the resilient force of the wire by the spring turns the two screwing members in the direction of screwing rotation to prevent the occurrence of the failure and prevent the occurrence of the failure. Always acts in the screwing rotation direction of the two screwing members, so that the two screws can be tightly connected to each other and the connection between the pair of pipes can be firmly maintained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a pipe joint connection maintaining device according to the present invention. FIG. 2 is a longitudinal sectional view of a pipe joint in a detached state with a wire removed. FIG. 3 is a front view of the connection maintaining device in a separated state. [Description of Signs] 1 Tube 3 Cap nut 6 Ring screw 12 Wire 15 Spring

Claims (1)

(57) [Claims 1] At least one screw member rotatably locked at one end of one tube and the other screw member screwed with the other screw member to form a pair of tubes. A wire having one end connected to the outer peripheral surface of the one screw member is wound around the outer peripheral surface of both screw members in the same direction as the screwing rotation direction of the two screw members. And connecting the other end of the wire to the outer peripheral surface of the other screwing member, and connecting a spring member that resiliently pushes the two screwing members in the rotational direction of the screw to the wire. Maintenance device.