JP4264957B2 - Bellows fittings for vibration isolation - Google Patents

Description

    The present invention relates to a vibration-proof bellows pipe joint capable of supplying a high-pressure fluid to a multilayer floor such as a high-rise building.

    Conventionally, anti-vibration joints are used for building construction and blunt piping. In such a vibration-proof joint, a pump is installed to supply high-pressure fluid from the lower layer side to the upper layer side, so that mechanical vibrations propagate through the piping and generate noise, In particular, anti-vibration joints are required on the suction side and discharge side of the pump.

    As an anti-vibration joint having excellent pressure resistance and vibration absorption, the one shown in FIG. 3 is known (Patent Document 1). In other words, the vibration-proof joint 1 is composed of a plurality of eyebrows bellows tubes 2 in which thin plates with alternately connected peaks 2a and valleys 2b are stacked, which is significantly larger than a bellows tube having a single eyebrow structure. The pressure resistance is improved, and a pair of left and right flange portions (projections) 3 and 3 connected to other members are fixed to both ends of the bellows tube 2 to prevent vibration in the axial direction of the tube body. It has a structure like this.

The pair of left and right flange portions 3, 3 are provided with through holes 4, 4, respectively, and a dedicated body 5 is inserted between the through holes 4, 4.
Disc springs 5a, 5a and cushioning materials 5b, 5b made of synthetic rubber, synthetic resin or the like are inserted into both ends of the rod-like body 5, and screw parts 6, 6a, 6a and nuts 6b, 6b are inserted through the flat washers 6a, 6a. 6. In addition, 7 and 7 are attachment holes for pipe connection drilled inside the through holes 4 and 4.

Patent Document 1 (Japanese Patent Laid-Open No. 10-252963)

    Such an anti-vibration joint 1 is a system in which a pair of left and right flange portions 3 and 3 are connected by a rod-like body 5, so that even if a high-pressure fluid circulates in the pipe of the joint 1, the axial extension, etc. The change is prevented. Further, even if the joint 1 is subjected to vibration by a feeding pump (not shown), the vibration is stretched and absorbed from the pressure resistant structure of the bellows pipe 2 which is not a single layer and has high pressure resistance, and between the flange portions 3 and 3 The vibration is not absorbed and transmitted by the elastic action of the disc springs 5a, 5a and the cushioning materials 5b, 5b interposed between them.

    Therefore, vibrations, pulsations, and the like are blocked by the structure of the joint 1 and are not transmitted to the discharge-side piping or the like, and the piping state can be maintained for a long time. For example, although it is suitable as a joint for high-pressure water supply such as a high-rise building of 20 kg / cm 2 or more, it is composed of a plurality of bellows tubes 2 in which thin plates are stacked, so that it cannot be manufactured and manufactured at low cost. There is. In addition, rubber joints and metal joints have the following problems.

    In other words, rubber joints are excellent in terms of covering and protecting the joints from the outside, but they tend to deteriorate or break down depending on the fluid conditions used, such as temperature, pressure, and fluid. There is a problem that it is easy to cause the next disaster. Metal joints are superior to rubber joints in terms of fluid conditions such as temperature, pressure, and fluid. On the other hand, if the joint is formed as a wavy bellows tube, stress is applied to both ends. Fatigue failure due to concentration tends to occur, and cracks cause complaints. In addition, both joints have thrust (cross-sectional area × internal pressure) due to internal pressure, and since the bolts are attached to prevent the axial extension, there is a problem that the vibration isolation performance is deteriorated.

    The present invention has been made in view of the above circumstances, and its purpose is to have excellent vibration absorption even in a state where the bellows tube has a single-layer structure, and to transmit vibration, pulsation and the like by the joint. An object of the present invention is to provide a vibration-proof bellows pipe joint that can be reduced.

In order to solve such a problem, the present invention provides a vibration-proof bellows in which a pair of flange portions are arranged at both ends of a bellows pipe and a high-pressure fluid is fed into the bellows pipe as described in claim 1. In the pipe joint, the bellows pipe is made of a metal having a single layer structure, and its outer peripheral portion is covered with a rubber or resin exterior body by an axial extension preventing member, and at least the axial extension is prevented. In addition, the extension preventing member is formed of a spanning member between flange portions that is passed through the exterior body and spanned between a pair of flange portions, and is installed in a stretched state in the left-right direction. And According to a second aspect of the present invention, the intermediate ring standing on the valley portion at the center of the bellows pipe maintains the spanning member between the flange portions.

According to the first aspect of the present invention, the inner surface side of the joint has a single layer structure of a metal bellows tube, but is sufficiently excellent in vibration absorption as compared with a multilayered bellows tube, and a rubber member. Compared to the above, it is possible to provide a low-cost joint that can prevent deterioration due to temperature, pressure, fluid, etc. , and the outer peripheral portion of the bellows pipe is prevented from being stretched in the axial direction. A dent or the like can be avoided, and the metal bellows tube can be expanded and contracted uniformly to prevent stress concentration and improve durability.
In addition, it is possible to prevent the expansion due to the thrust due to the internal pressure of the bellows pipe with the built-in flange portion spanning member, and of course, the product can be simplified as well as the improvement of the vibration isolation performance compared with the conventional bolt. it can.
According to the second aspect of the present invention , the intermediate ring of the axial extension preventing member is erected on the trough at the central portion of the bellows tube, and the spanning member between the flanges is resistant to the pressure of the rubber member or the like. Can be maintained well.

    Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view showing a state in which the upper half of the present invention is crushed, and FIG. 2 is a partially broken front view of the upper half showing another embodiment of FIG.

    The schematic configuration of the joint 10 includes a metal bellows tube 11 disposed at a central position, a pair of flange portions 12 and 12 disposed on the left and right sides of the metal bellows tube 11, and an outer peripheral portion of the bellows tube 11. It is comprised by the exterior body 14 which is an elongation stop member coat | covered by.

    The bellows tube 11 is made of a metal having a single-layer structure, has a bellows portion in which a peak portion 11a and a valley portion 11b are continuous, and is mainly formed as a cylindrical shape that can expand and contract in the axial direction. The flange portions 12 and 12 are respectively arranged on both end sides of the bellows tube 11 and fixedly attach the bellows tube 11.

    The bellows tube 11 may be made of metal, but is more preferably made of stainless steel, and may be made of austenitic stainless steel or ferritic stainless steel.

The exterior body 14 that is an expansion preventing member is externally mounted on the bellows pipe 11 sandwiched between the flange portions 12 and 12 on both ends, and prevents expansion and contraction by covering the bellows pipe 11 and preventing expansion and contraction due to the internal pressure of the bellows pipe 11. Fulfill.
As materials that have an anti-elongation action, there are rubber materials, synthetic resin materials, and foamed resin materials as exterior bodies, and various rubber materials such as propylene rubber, nitrile butadiene rubber, chloroprene rubber, butyl rubber, acrylic rubber, and ethylene acrole rubber. Among them, silicon rubber, polyisoprene rubber, polybutadiene rubber, polychloroprene rubber, fluorine rubber and the like are suitable as the rubber material for vibration isolation, and are appropriately selected according to the intended use.

Synthetic resin materials such as vinyl chloride, polystyrene, high-impact polystyrene, low-density polyethylene, high-density polyethylene, and polypropylene are also excellent in terms of cost. It is also effective.

    A more specific structure of the joint 10 will be described. A bellows tube 11 having a cylindrical single eyebrow structure formed in a bellows shape is formed at a straight cylindrical end portion at both ends thereof, and an outer end portion is provided in the gap between the mounting holes 12a and 12a of the left and right flange portions 12 and 12. It is inserted to be flush with. Further, the pipes 13 and 13 are inserted into the gaps between the mounting holes 12a and 12a of the left and right flange portions 12 and 12 and the straight cylindrical end portion of the bellows tube 11, and in particular, the left flange portion 12 and the pipe 13 are inserted in the drawing. Is bent from the flange portion 12 so as to be flush with the outer periphery of the flange portion 12. This coupling method is not limited to the above-described method, and the design can be changed as appropriate. In addition, the black part in a figure has shown the welding part.

    The exterior body 14 that is an expansion preventing member is attached to the outer peripheral portion of the bellows tube 11 sandwiched between the flange portions 12 and 12 on both ends, and mainly protects and extends in the axial direction of the flange portions 12 and 12. The bellows tube 11 is protected by covering with a rubber outer body 14, and the anti-elongation action is performed by a metal wire lobe 16 stretched from side to side. In addition, although the anti-stretching action in the radial direction is smaller than that in the axial direction, it is taken into consideration.

    Although the material used for the stretch preventing member has been described as a metal wire rope, the invention is not limited to this, and the design can be changed as appropriate. For example, a material obtained by twisting thin metal wire lobes may be used. As long as the length of the bellows tube 11 extending between the first and second members 12 can be maintained firmly and constant, the design can be changed as appropriate.

    That is, the rubber exterior body 14 vulcanizes the rubber member with the wire lobe 16 stretched. Both ends of the wire lobe 16 installed in a state of being stretched in the left-right direction are fixed in the radial direction by bolts 17 and nuts 18.

    Reference numeral 19 denotes an intermediate ring, which is provided at the center of the bellows tube 11 and is fixed to the trough 11b, and the wire lobe 16 is inserted into the hole 19a so as to maintain a good tension.

    Thus, according to the present invention, the left and right sides are a pair of flange portions 12, 12, the inner surface side of the joint 10 is a metal single-layer bellows tube 11, and the outer surface side is a rubber exterior. Since the outer sheath 15 made of rubber is covered with the wire rope 16 extending over the flange portions 12 and 12 on the left and right sides, the outer sheath 15 made of rubber is covered with the body 15, so that it is compared with a bellows pipe having a multilayer structure. In addition, the rod-shaped body is not bridged between the left and right flange portions, and expansion and contraction can be prevented by the action of the wire lobe 16.

    FIG. 2 shows another example of the state in which the wire rope 16 is bridged, and both ends thereof are fixed in the axial direction by bolts 17 and nuts 18. As described above, the design of the positions of the bolt 17 and the nut 18 can be appropriately changed. In other words, the fastening as the flange portion spanning member 16 is not limited to the fastening of the bolt 17 and the nut 18, and any method can be assumed.

    The exterior body 14 which is an extension preventing member can be formed not only by forming the covering body 15 with a constant thickness but also by embedding an extension prevention member interposed in the radial direction or the axial direction. This is achieved by applying the reinforcing material together with the reinforcement. All the above-mentioned materials can be considered for the material of the reinforcing material.

According to the present invention configured as described above, since the inner surface side of the joint is a metal bellows tube, deterioration due to temperature, pressure, fluid, and the like can be prevented as compared with a rubber member. In addition, since the outer surface side of the joint is covered and protected by a rubber or synthetic resin exterior body, it is possible to avoid dents and the like, and the metal bellows tube can be expanded and contracted evenly to reduce the stress. Centralization can be prevented.
Furthermore, the exterior body made of rubber or synthetic resin can prevent the extension caused by the internal pressure of the metal bellows pipe with the built-in flange part spanning member, compared to conventional bolts etc. Of course, the product can be simplified as well as the improvement of the anti-vibration performance.

    It can be used not only for vibration isolation joints on the discharge side and suction side of the bomb, but also for joints that can absorb expansion and contraction and displacement due to temperature changes in the piping. The resulting noise can also be silenced.

It is a front view which shows the state which crushed the upper half part of this invention. It is a partially broken front view of the upper half part which shows the other Example of FIG. It is a partially fractured front view of the upper half part showing a conventional vibration-proof joint.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Joint 11 Bellows pipe 12 Flange part 13 Pipe 14 Exterior body (extension prevention member)
15 Covering body 16 Flanging member 17 Bolt 18 Nut 19 Intermediate ring

Claims (2)

In the bellows fitting for vibration isolation, a pair of flange portions are arranged on both ends of the bellows pipe, and a high-pressure fluid is fed into the bellows pipe.
The bellows tube is made of a single-layer metal, and the outer peripheral portion thereof is covered with a rubber or resin exterior body by an axial extension preventing member, and at least the axial extension is prevented, and The anti- stretch member comprises an inter-flange spanning member that is passed through the exterior body and spans between a pair of flange portions, and is installed in a stretched state in the left-right direction. Bellows pipe fittings. 2. The vibration-proof bellows pipe joint according to claim 1, wherein the intermediate ring standing on the valley portion at the center of the bellows pipe maintains the spanning member between the flange portions .

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