JP2852766B2 - Capstan type vibration damping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vibration damping device for protecting piping of a plant from sudden vibration such as an earthquake.

[Prior art] As a pipe vibration control device, (1) Slow displacement of a pipe due to a temperature change is not affected. (2) Abrupt vibration caused by an earthquake or the like is affected. It is necessary to satisfy the conditions. On the other hand, at present, three types, a spring type, a hydraulic type, and a mechanical snubber type, are known, but only a mechanical snubber satisfies the above three conditions. However, the high cost for structural reasons hinders widespread use.

For this reason, a completely different concept is used, using a high-tensile mild steel sheet or the like, one end of which is connected to a pipe and the other end of which is connected to a structure to absorb vibration energy by plastic deformation of the plate. -146929. However, this structure is difficult to use effectively unless the length of the expansion and contraction stroke of the pipe due to the thermal change is within an appropriate range.

[Means for Solving Problems] Using an outer cylinder and an inner cylinder that can be relatively moved in and out, a friction rod is fixed to the outer cylinder on a diameter line, and a long hole is formed in the inner cylinder to avoid a collision with the friction rod. Wire ropes respectively locked to both lids of the inner cylinder are engaged with the friction rods. That is, the vibration is damped by the frictional resistance between the wire rod and the friction bar due to the relative movement of the two cylinders. A rope with its end wrapped around a locking rod can be pulled out slowly when pulled, but exhibits high frictional resistance when pulled sharply. It is generally known as capstan action, but it is a use of it.

This structure satisfies the three conditions described at the outset and can cope with slow expansion and contraction of the pipe regardless of the length of the stroke.

Example A drawing will be described. 1 comprises an outer cylinder 1, a friction bar 2, an inner cylinder 3, and a wire rope 4. Outer cylinder 1
Has an opening at one end and a lid 1a with a handle at the other end, and a friction bar 2 is fixed at the center in the diameter direction. The inner cylinder 3 has a lid 3a and a lid 3b with a pull at both ends, is slidably inserted into the outer cylinder, and has an elongated hole 3c for allowing the friction bar 2 to pass freely. One end of the wire rope 4 is locked to the lid 3b, and after the friction rod 2 is wound, the other end is locked to the lid 3a so as to adjust the tension. The stopper metal 5 is used for locking to the lid 3a. The retainer 5 has a hole on one side of the cylinder so that a wire rope can be inserted and crimped, and the other side is threaded with a nut 6. The metal fitting 5 is inserted into a hole formed in the lid 3a, and the tension of the wire rope can be adjusted by tightening the nut 6. If necessary, a disc spring (not shown) is inserted between the nut 6 and the lid 3a. In order to avoid mutual contact between the wire rope wound around the friction bar, it is desirable to use the guide cylinder 7 shown in FIG. The guide cylinder 7 has a wire rope groove spirally formed on the outer periphery, and is inserted and fixed to a friction bar.

The device is used with one pull connected to the plumbing and the other pull connected to the structure. At that time, with the tension of the wire rope, the displacement of the pipe due to heat change is allowed with an appropriate frictional resistance,
Adjust with the retaining bracket. In the event of an earthquake, the device adjusted in this way causes the above-mentioned capstan effect due to a sudden reciprocation of the wire rope, so that the vibration is damped by rapidly increasing the resistance.

FIG. 4 shows another embodiment. The provision of the outer cylinder 1, the friction bar 2, and the inner cylinder 3 is the same as that in FIG. A wedge bar 8 is arranged in parallel on both sides of the friction bar 2 and both ends are spacer plates 9.
Is positioned with. The spacer plate 9 is a strip-shaped plate having a hole in the center. The wedge bars 8 are fixed to both sides, and the friction bar 2 is rotatably inserted into the center hole. One end of the plurality of flat ropes 10 is locked by the lid 3b, and three rods 8,
The other end is connected to the stopper 5 of the lid 3a.
In this case, there is an advantage that the friction area is increased by using a flat rope and a guide cylinder is not required.

[Effect] While the mechanical snubber is expensive because of the configuration that inevitably uses a ball screw, the present invention significantly reduces the price due to its straightforward configuration, and can be used generously in the required places of piping. To It is possible to cope with large and small expansion and contraction due to thermal change of the piping.

[Brief description of the drawings]

FIG. 1 is a front view of the present invention, FIG.
FIG. 3 is a front view of a guide cylinder, and FIG. 4 is a front view of another embodiment. 1 ... outer cylinder, 2 ... friction rod, 3 ... inner cylinder, 4 ... wire rope, 5 ... stopper metal fittings, 6 ... nut, 7 ... guide cylinder, 8 ... wedge rod, 9 ... ... spacer plate, 10 ... rope.

Claims (2)

(57) [Claims] 1. An outer cylinder having an open end and a friction bar fixed in the center in a diametrical direction at a center portion, and an inner cylinder inserted into the outer cylinder so as to be able to move in and out, and having an elongated hole through which the friction rod can pass and having lids at both ends. And a wire rope wound around a friction rod at the center and fixed at both ends to both ends of the inner cylinder so that tension can be adjusted. One of the outer ends of both cylinders is connected to a fixed body and the other is connected to a vibrating body. Capstan type vibration damping device. 2. An outer cylinder having an opening at one end and having a friction bar fixed in a diameter direction at a center portion, and an inner cylinder having a slot at both ends which is inserted into the outer cylinder so as to be able to enter and exit, and has an elongated hole through which the friction bar can pass. And a pair of symmetric wedge bars having a pair of spacer plates inserted into the friction bar at the center and both ends fixed to the spacer plates on both sides of the friction bar, and a friction bar and wedge bars at both ends at the center. And a plurality of wire ropes which are alternately engaged with each other and are locked at both ends to both ends of the inner cylinder so as to be adjustable in tension. One of the outer ends of the two cylinders is connected to the fixed body and the other is connected to the vibrating body. And a capstan type vibration damper.