JP4338675B2 - Flexible joint for pipe - Google Patents

Description

  The present invention relates to a flexible joint such as a fume pipe that is propelled or buried in soil, and relates to a technical field that sufficiently performs water-stopping and waterproofing of a joint portion.

  Conventionally, a flexible joint is used for a fume pipe or the like buried in the soil. This flexible joint is provided at the connecting part of the pipe, and absorbs displacement and vibration such as bending and eccentricity of the pipe caused by ground fluctuation, earthquake, etc., and prevents breakage and leakage of the pipe. (For example, patent document 1).

  By the way, in Patent Document 1, the joint is in the form of a rubber thin film, and sufficient strength against external pressure such as earth pressure, internal water pressure or the like cannot be obtained and there is a risk of breakage.

  In addition, since the joint is made of a rubber thin film, a shearing force is generated in the connecting part of the tube due to external pressure, and the connecting position of the tube is displaced in the radial direction, so that there is a risk that the flow path cannot be secured sufficiently and the flow down function is hindered. .

  Further, since flexibility is obtained by expansion and contraction (deformation) of rubber, there is a problem that the life is reduced due to fatigue of rubber.

No. 4-10468

  Therefore, a small-diameter pipe concentric with the fume pipe is provided in the opposing connection end of the fume pipe, that is, the joint part, in the opposite direction with the annular step surface as a boundary, and an annular or cylindrical shape made of natural or synthetic rubber on the outer circumference of both small-diameter pipes An elastic waterstop is fitted, the inner periphery of the base of the waterstop is fastened and fixed to the outer periphery of the base of one of the small-diameter pipes, and the main body and the tip of the waterstop are fixed to the outer periphery of the other small-diameter pipe. Has been developed (for example, Patent Document 2).

  However, the waterstop body may have high elasticity, but lacks flexibility, flexibility, and stretchability. Therefore, the bent joint portion is flexible to the shearing force, tensile force, and compression force applied to the waterstop body. There is a problem that it is difficult to cope with the above, and the flexibility is poor (for example, Patent Document 2).

JP 2005-48886

In the opposite end connection part such as a plurality of fume pipes arranged in series on a common center line, the present invention,
An object of the present invention is to obtain a flexible joint having a high flexibility and a high flexibility by tightly fitting a flexible short cylinder made of rubber or the like over the opposite end portion.

In order to achieve the above object, according to the present invention, firstly, at the opposing ends of a plurality of equal diameter tubes arranged in series on a common center line, a small-diameter short tube is provided to project in the opposing direction at each of the opposing ends. A flexible bellows tube that can be stretched and formed of a bellows-like bent portion is fitted over the outer circumferences of both small-diameter short tubes, and the outer periphery of the base end portion of the bellows tube is fitted to the outer periphery of the small-diameter short tube of one equal-diameter tube A steel pipe that forms a cylindrical space in which the tip of the bellows cylinder is slidably fitted to the outside of the small-diameter short cylinder of the other equal-diameter pipe is placed on the common center line with the other equal-diameter pipe. fixed becomes, the outer peripheral surface and inner and outer pressure-contact fitting freely inner peripheral surface and the sliding of the steel tube of smaller diameter short tube of the other equal-diameter tube at the distal end of the bellows barrel toward the next two A flexible joint for pipes with two crotch edges,
Consists of.

  Therefore, if the direction of the equal diameter tube in series with the direction of the common center line is changed, the opposing end surface of the small diameter short cylinder facing the opening opens in the changing direction, the flexible bellows cylinder expands and contracts, and the base end of the flexible bellows cylinder The outer periphery moves together with the outer periphery of one small-diameter short cylinder, and the tip of the bellows cylinder slides in the cylindrical space between the other small-diameter short cylinder and the steel pipe to stop water entering from the outside. To do.

The water stop is performed by slidably pressing the inner and outer circumferences of the tip of the bellows cylinder to the inner circumference of the steel pipe and the outer circumference of the other small-diameter short cylinder, and the base end of the bellows cylinder It is done by tightening and fixing to the outer periphery of the small diameter short cylinder
Between the opened opposing small-diameter short cylinders, water is stopped by the bellows cylinder as described above.

  In the present invention, as described above, the flexible bellows tube can be expanded and contracted by the outward and inwardly bent portions, and even if the series equidiameter pipe bends and the opposing end surface of the joint portion opens, the above-mentioned bellows tube The amount of compression and tension is large, and the tip of the flexible bellows cylinder slides, so that it is rich in flexibility and water stoppage at the bent portion.

  A plurality of equal-diameter pipes (fume pipes) 1, 1 ′ made of cement or resin are connected in series on a common center line c.

  In the connecting portion, short tubes 2 and 2 'having a smaller diameter than the outer diameter of the equal diameter tubes 1 and 1' are provided in the opposite direction at the opposite ends of the equal diameter tubes 1 and 1 ', respectively.

  One short tube 2 is shorter than the other short tube 2 ′ in the direction of the center line c (about ½), and the outer peripheral surface and the opposite front end surfaces 2 ″ and 2 ″ are covered with the steel plates 7 and 7. The base step surfaces 8, 8 'of the cylinders 2, 2' are covered with annular disks 8 ", 8".

  A steel pipe 4 is fixed to form a cylindrical space s on the outer periphery of the annular disk 8 ″ at the base end of the other short cylinder 2 ′, and the tip of the other short cylinder 2 ′ (right side of FIGS. 1 and 2). ) Toward the outer periphery of the annular disk 8 ″ of one short cylinder 2, and a gap t is interposed between the outer periphery and the tip 4 ′ of the steel pipe 4.

Then, a flexible bellows tube 3 made of natural or synthetic rubber is fitted over the outer peripheral surfaces of both the small-diameter short tubes 2 and 2 '.
One semi-circular band b, b is applied to the outer periphery of the base end portion 3a of the bellows tube 3 on the outer periphery of the base portion of one of the small diameter short tubes 2, and the abutting end portions b ′ of the bands b, b are applied. By tightening b ′ with bolts b ″ and b ″, the base end portion 3a of the bellows tube 3 is fastened and fixed to the outer peripheral surface of one small-diameter short tube 2.

Tip 3 b of the bellows tube 3 is inserted into the cylindrical space s, thereby slidably press fitted on the outer peripheral surface of the inner peripheral surface of the steel pipe 4 and the other small diameter short tube 2 '.

  As shown in FIGS. 1 (a) and 1 (b), the distal end portion 3b includes inner and outer forward bifurcated edges 9 and 9 and an outer rearward edge 10, and the distal end portion 3b is an outer periphery of the other small-diameter short cylinder 2 ′. Crimp to the surface and the inner peripheral surface of the steel pipe 4.

  An outer rearward edge 11 is provided on the outer periphery of the base end portion 3a, and this is also crimped to the inner peripheral surface of the distal end portion 4 'of the steel pipe 4 as shown in FIGS.

  Further, as shown in FIGS. 1A and 1B, the bellows tube 3 is provided with bellows-like outwardly curved portions 3 'and 3' and bellows-like inwardly curved portions 3 "and 3" as shown in FIGS. The bellows cylinder 3 can be expanded and contracted, and follows the bending of the opposing end connecting portion of the equal diameter tubes 1 and 1 ′.

  A collar 5 is provided on the outer peripheral surface of the steel pipe 4, and both ends 5 ′ and 5 ′ of the collar 5 are fixed to the outer periphery of the opposed equal-diameter pipes 1 and 1 ′ with rebars 12 and 12. A plurality of small slits 6 and 6 are formed in a plurality of rows at zigzag positions along the circumferential direction.

  Accordingly, when the equal diameter tubes 1 and 1 'are deflected and bent as shown in FIG. 2 at the connecting portion, the small slits 6 and 6 at the staggered position are opened, and the collar 5 is shown in FIGS. ) Opening 13 as shown.

  In this state, the tip 3b of the bellows tube 3 is in pressure contact with the inner peripheral surface of the steel pipe 4 and the outer peripheral surface of the small-diameter short tube 2 'and slides in the space s in a water-stopped state.

  Since the bellows cylinder 5 has a bellows shape, the sliding is relatively flexible in compression or tension, and easily corresponds to the bent arrangement of the equal diameter tubes 1 and 1 ′ (FIG. 2).

  In the figure, reference numeral 14 denotes a facing seal of the small-diameter short cylinders 2 and 2 ′, and reference numeral 15 denotes one end supporting rebar of the steel pipe 4.

(A) is a longitudinal side view of the flexible joint for pipes of the present invention, and (b) is a longitudinal sectional view of a flexible bellows tube. It is a longitudinal cross-sectional view of the bending joint part of an equal diameter pipe. (A) The figure is a perspective view of a bent state of two in-line equal-diameter pipes, and (B) is a partially enlarged perspective view of (A).

Explanation of symbols

c common center line 1, 1 ′ equal diameter tube 2, 2 ′ small diameter short tube 3 flexible bellows tube 3 ′ outward curve portion 3 ”inward curve portion 3 a base end portion 3 b distal end portion 3 c central portion s cylindrical space 4 steel tube 5 Color 6 Small slit

Claims (1)

At opposite ends of a plurality of equal diameter tubes arranged in series on a common center line,
A small-diameter short cylinder is protruded in the opposing direction at each of the opposing ends,
Fitting a flexible bellows tube that can be stretched and formed of a bellows-shaped curved portion over the outer circumference of both the small diameter short tubes,
Fasten the outer periphery of the base end of the bellows tube to the outer periphery of the small diameter short tube of one isometric tube,
A steel pipe forming a cylindrical space in which the tip of the bellows cylinder is slidably fitted to the outside of the small diameter short cylinder of the other equal diameter pipe is fixed to the other equal diameter pipe on a common center line, The inner side and the outer side of the outer peripheral surface of the small-diameter short tube of the other equal-diameter tube and the inner peripheral surface of the steel tube that are slidably press-fitted to the front end of the bellows tube are divided into two. A flexible joint for pipes with a crotch edge.

Images