JPH08268682A - Vibration damping device for hoisted cargo - Google Patents

Abstract

PURPOSE: To provide a device for converging deflecting a hoisted cargo in a short time without causing damage and hazardousness of the hoisted cargo or hoist fitting. CONSTITUTION: A braking cylinder 2 is concentrically fixed relating to a perpendicular line O of passing through a hoist center point by a runnable hoist device in an almost upper limit position of a lift stroke of a hoist fitting 3, to provide an almost tapered shape with a diameter gradually decreased toward upward. The hoist fitting 3 can be received in the braking cylinder 2, also to be formed in size incapable of passing through an upper end opening 2a of this braking cylinder, and a damper 4 provided in the periphery of the hoist fitting 3 is formed of a movable piece energized so as to be always protruded to the outside by an internal coil spring, to converge deflection by bringing this movable piece into contact with an internal peripheral surface of the braking cylinder 2 in a lift stroke of the hoist fitting 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for promptly suppressing swinging of a hoisting load that occurs when hoisting a load through a hoisting wire.

[0002]

2. Description of the Related Art Swinging of a load suspended by a hoisting device such as a traveling winch or an overhead crane (pendulum motion)
Conventionally, the amplitude is converged by waiting until the amplitude naturally converges without performing the next operation, or by unloading a suspended load, re-implanting, and then lifting again. Further, the shake of the hoisted load during horizontal movement is manually suppressed by a method of pulling an intermediary rope tied to a hanger or the like from diagonally below.

[0003]

However, since it takes a long time for the vibration to converge naturally, waiting for the vibration to spontaneously converge with the suspended load hoisted results in a longer transportation cycle, which leads to work. The efficiency is extremely low. In this case, it is possible to accelerate the convergence of the amplitude by lowering the suspended load that has been lifted and re-floating, but it is difficult to completely stop the shake, and moreover, it is suspended by the impact during re-floating. There is a risk of damaging the load or the hanger. Also, when the worker manually suppresses the shake of the suspended load during horizontal movement with the interposition rope, the worker with this interstitial rope may be vigorously pulled by the movement and shake of the suspended load,
It is a danger.

The present invention has been made under the circumstances as described above, and its technical problem is to prevent swinging of a suspended load without causing damage or danger of the suspended load or the suspender. It is to provide a device for converging in a short time.

[0005]

As a means for effectively solving the above-mentioned technical problems, the vibration damping device for a suspended load according to the present invention is concentric with a vertical line passing through the center of suspension by the hoisting device. A substantially tapered braking cylinder having a gradually decreasing diameter is fixed to the position, and can be accommodated in the braking cylinder at the lower end of a hoisting wire that hangs down from the hoisting device through the braking cylinder. In addition, a hanging tool having a size that does not pass through the upper end opening is provided, and a required number of dampers are arranged on the outer circumference of the hanging tool. In this case, more preferably, the braking cylinder is fixed integrally with, for example, the frame of the hoisting device.

[0006]

The braking cylinder is centered on the center point of suspension by the hoisting device by contact with a damper arranged on the outer circumference of the hoisting tool at the lower end of the hoisting wire suspended from the hoisting device through the inner circumference of the hoisting device. This restricts the pendulum motion of the suspension, and since this braking cylinder is formed with a gradually smaller diameter toward the upper side, the suspension suspended by the hoisting wire can be raised in this braking cylinder. Along with this, the allowable amplitude of the pendulum movement is converged, and eventually the entire damper on the outer circumference of the hanging tool comes into contact with the braking cylinder, whereby the shake is completely stopped.
The damper absorbs shock and noise due to contact with the inner peripheral surface of the braking cylinder, and absorbs kinetic energy due to shake to effectively attenuate it.

The braking cylinder is preferably fixed integrally with the frame of the hoisting device. Therefore, even if the hoisting device itself moves, such as a traveling winch or a winch of a crane, the braking cylinder moves with the hoisting device and always passes through the center point of suspension by the hoisting device. It is concentric with the vertical line and stops the swing of the suspended load caused by the movement of the hoisting device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a preferred embodiment of a device for damping a suspended load according to the present invention. Reference numeral 1 is a pair of hoisting wires wound by a hoisting device (winch) not shown. Reference numeral 2 is a braking cylinder fixed to the frame of the hoisting device via a pair of brackets 22 and 3 is a hoisting wire 1 hung down through the inner circumference of the braking cylinder 2 via a movable pulley 31. 4 is a damper provided on the outer periphery of the suspender 3 at equal intervals in the circumferential direction (for example, 6 equally spaced). That is, the hoisting device and the hoisting tool 3 suspended by the hoisting device conveys unillustrated earth and sand as a hoisting load to a predetermined location.

The braking cylinder 2 is arranged at a substantially upper limit position of the lifting / lowering stroke of the hoisting device 3 concentrically with respect to a vertical line O passing through a center point (not shown) of the hoisting device and upward. It presents a substantially tapered shape with a gradually decreasing diameter. The casing 33 of the suspender 3 is formed in such a size that it can be accommodated in the braking cylinder 2 and cannot pass through the upper end opening 2a thereof, and the earth and sand grab 32 is opened and closed in the casing 33. It has a built-in drive mechanism. The hoisting device is movable along a predetermined track laid in a high place like a traveling winch.

The damper 4, as shown in FIG.
Of the casing 33, a movable piece 41 arranged in a partially accommodated state in each of the chambers 33a recessed in the circumferential direction 6 at equal positions, and the upper end of the movable piece 41 is the upper end of the open edge of the chamber 33a. And a movable piece 41 for rotatably supporting the shaft 42.
The expansion rod 43 whose both ends are respectively connected via the universal joints 43a and 43b between the lower inner surface of the casing and the chamber wall 33b on the side of the casing 33 which faces the casing 33, and the expansion rod 43 is held on the outer periphery of the expansion rod 43. The movable piece 41 is provided in the chamber 33a.
And a coil spring 44 for urging the coil spring 44 so as to always project outward. The chamber 33a has a size that allows the movable piece 41 to retreat about the shaft 42 in the direction of contracting the expansion rod 43 and the coil spring 44, and a movable edge 33c formed at the lower end of the chamber 33a The amount of protrusion of the movable piece 41 from the casing 33 is restricted by the interference with the convex edge 41a formed on the lower end of the piece 41.

In the above-mentioned structure, when the hoisting device 3 is hoisted by hoisting and rotating the hoisting device after the earth and sand is collected by the earth and sand grab 32, the hoisting wire 1
The hoisting device itself may move to the hoisting device 3 suspended through the hoisting device due to the deviation between the landing position of the earth and sand grab 32 and the hoisting center point (vertical line O) by the hoisting device. As a result, an arc-shaped swing (pendulum motion) is generated around the center point of suspension by the pair of hoisting wires 1 suspended from the hoisting device. However, when the casing 33 of the suspender 3 moves upward to the inner circumference of the lower end of the braking cylinder 2,
When the amplitude of the pendulum movement is larger than the inner diameter of the lower end of the braking cylinder 2, one of the dampers 4 arranged at equal intervals on the outer periphery of the suspender 3 as shown in FIG. Is in contact with the inner peripheral surface of the lower part of the braking cylinder 2, so that the displacement of the suspender 3 due to the pendulum motion is restricted within the range of the inner diameter of the lower end of the braking cylinder 2.

At this time, in the damper 4, the movable piece 4
At the moment when 1 comes into contact with the inner peripheral surface of the lower portion of the braking cylinder 2, the dashed-dotted line 4 in FIG. 2 resists the biasing force of the coil spring 44.
As indicated by 1 ', the shaft 42 is moved backward into the chamber 33a. Therefore, the elasticity of the coil spring 44 effectively absorbs the impact due to the contact with the braking cylinder 2, and the expansion and contraction rod 43 is expanded and contracted when the movable piece 41 is retracted due to the contact with the braking cylinder 2. Since it acts as a kind of dashpot, it effectively attenuates the energy of the pendulum motion.

By the above-mentioned operation, the amplitude of the pendulum movement of the suspension 3 can be suppressed within the range of the inner diameter of the lower end of the braking cylinder 2.
In the next half cycle, the damper 4 comes into contact with the inner peripheral surface of the braking cylinder 2 again on the side opposite to the contact position shown in FIG.
This is because the braking cylinder 2 is formed in a taper shape in which the diameter gradually becomes smaller toward the upper side, so that as the suspending tool 3 is moved up in the braking cylinder 2, the pendulum is brought into contact with the damper 4. This is because the inner diameter of the braking cylinder 2 that limits the amplitude of the movement is narrowed. Therefore, the amplitude of the hanger 3 is equal to that of the braking cylinder 2.
In FIG. 3, a broken line arrow F is shown in FIG.
It will be converged as shown in. Then, as shown in FIG. 4, the movable pieces 41 of all the dampers 4 on the outer circumference of the hoisting device 3 are stopped when the hoisting device 3 reaches the upper limit position of the hoisting device and stops. It comes into contact with the inner peripheral surface of the upper part of the body 2, and the shake is completely stopped.

The inner peripheral surface of the braking cylinder 2 or the outer surface of the movable piece 41 of the damper 4 is preferably covered with an elastic body such as an elastomer. Thereby, the impact sound when the movable piece 41 collides with the inner peripheral surface of the braking cylinder 2 can be reduced. In addition to the configuration of the above-described embodiment in which the movable piece 41 is actuated around the shaft 42, the damper 4 does not use the coil spring 44, for example.
Is a leaf spring, or the entire movable piece 41 is the chamber 33.
Various types such as a cylindrical shape that slidably projects with respect to a can be applied.

Further, in the above-mentioned embodiment, the suspending tool 3 has been described as having the earth and sand grab 32 for conveying the earth and sand, but one having a hook or the like for hanging a suspended load such as a construction material by slinging. Can be similarly applied.

[0016]

According to the present invention, the following effects are realized. (1) In the process of hoisting the suspended load, the runout is surely converged,
Since it is not necessary to wait for the natural convergence, the transportation cycle of the suspended load is significantly shortened and the work efficiency is improved. (2) Since it is not necessary to lower the suspended load that has been lifted and re-implant in order to accelerate the convergence of the swing, there is no risk of damaging the suspended load or the hanging equipment, and the swing can be completely stopped. (3) It is safe because the worker does not have to manually suppress the shake of the suspended load during horizontal movement by using an intermediary rope. (4) Since no power is used to converge the shake, it can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a preferred embodiment of a vibration damping device for suspended loads according to the present invention.

FIG. 2 is a sectional view showing an internal mechanism of a damper 4 in the above embodiment.

FIG. 3 is an explanatory diagram showing a process of convergence of shake of the hanging device 3 according to the above-described embodiment.

FIG. 4 is an explanatory view showing a state in which the swing of the suspender 3 is completely stopped by the above embodiment.

[Explanation of symbols]

 1 hoisting wire 2 braking cylinder 3 hanging tool 4 damper 41 movable piece 43 expansion rod 44 coil spring

Claims (2)

[Claims] 1. A substantially tapered braking cylinder fixed at a position concentric with a vertical line passing through a hoisting device by a hoisting device and having a diameter gradually decreasing upward, and the hoisting device passing through the braking cylinder. A hoisting wire which is provided at the lower end of a hoisting wire hanging from the device and which can be accommodated in the braking cylinder and does not pass through the upper end opening; and a required number of dampers arranged on the outer circumference of the hoisting wire. A vibration damping device for a suspended load, comprising: 2. The vibration damping device for suspended loads according to claim 1, wherein the braking cylinder is fixed integrally with the frame of the hoisting device.