JP2001253684A - Overhead crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an overhead crane capable of reducing a vertical seismic response of a crane girder in the case of an earthquake. SOLUTION: A vertical damping member 6 having a damper 7 including viscous fluid 12 and a slider 8 is fixed in the crane girder 1, while a slider supporting board 9 is arranged in a building frame 10 end in the overhead crane traveling direction, and the slider 8 is arranged freely slidably to the slider supporting board 9. In this way, a vertical seismic response of the overhead crane due to a great earthquake is reduced without disturbing any movement of the overhead crane, and an overhead crane drop preventing function is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overhead traveling crane installed in a building such as a nuclear power plant, and more particularly to an overhead traveling crane excellent in earthquake resistance against a vertical earthquake load.

[0002]

2. Description of the Related Art As shown schematically in FIG. 3, an overhead crane installed in a reactor building of a nuclear power plant has a runway girder 5 and a traveling rail 4 installed in pairs on both sides of an upper part of a building frame. The crane girder 1 is arranged on the traveling wheel 3 above, and the crane girder 1 can travel along the traveling rail 4. The derailment prevention lug prevents the crane from dropping when an earthquake occurs. 2 are provided.

[0003] The derailment preventing lug is fixed to the crane girder 1 as shown in FIG. When an earthquake occurs, horizontal and vertical seismic forces are transmitted to the overhead crane via the building frame 10, and in this case, the overhead crane is held on the runway girder 5 by the derailment preventing lugs 2, and The structure improves the function of preventing the crane from falling to the floor.

[0004]

However, when a large earthquake with a large vertical seismic force occurs, the upward seismic motion component at the vertical natural frequency of the overhead crane may be larger than the gravitational acceleration. Crane running rail 4
It will rise from.

In this case, the lower portion of the derailment prevention lug 2 collides with the end of the runway girder 5, and the load generated at the derailment prevention lug 2 or the end of the runway girder 5 may exceed an allowable value. If the overhead crane rises and a large impact force is transmitted to the traveling rail 4 and the runway girder 5 at the time of landing, the runway girder 5 is largely deformed as a whole,
It may affect the fall prevention function of the overhead crane.

As a countermeasure for preventing the lifting of the crane body and alleviating the impact at the time of landing, for example, Japanese Patent Application Laid-Open No. Hei 8-231183 shown in FIG. 5 has been proposed.

[0007] A shroud case 15 is provided on a building frame 10 supporting a traveling rail 4 of a crane so as to surround a locus of movement of a wheel frame 14 of a crane body, and a resistance plate extending in the front-rear direction inside the shroud case 15 is provided. 16 is arranged horizontally, the slider 8 attached to the wheel frame 14 is engaged with the resistance plate 16, and the shroud case 1
5 is filled with a viscous fluid 12.

According to this structure, when a lifting force is generated in the crane main body due to an earthquake, the force is transmitted to the resistance plate 16 via the wheel frame 14 and the slider 8, and the viscous resistance of the viscous liquid 12 against the resistance plate 16. And the crane body is less likely to float. The viscous resistance of the viscous liquid 12 is also provided when the lifted crane body lands, so that the impact at the time of landing is reduced.

However, in the case of this structure, the shroud case 15 containing the viscous fluid 12 has a certain viscosity due to the outflow of the viscous liquid due to the earthquake or the incorporation of foreign matter such as dust, since the portion where the traveling wheels travel is open. The resistance cannot be maintained, and the predetermined function may not be satisfied.

In view of the above, the present invention has been made in consideration of the above-mentioned contents, and provides a structure for improving the earthquake resistance of a ceiling crane against a vertical earthquake response and improving a fall prevention function. It is.

[0011]

SUMMARY OF THE INVENTION The present invention relates to an overhead crane traveling on a traveling rail at an upper end of a runway girder disposed on a building frame, and a vertical damping member having a damper and a slider containing a viscous fluid is crane-mounted. A ceiling crane, which is fixed to the girder, and a slider support plate is provided at the end of the building supporting the runway girder in the traveling direction of the overhead crane, and the slider is disposed so as to be slidable with respect to the slider support plate. This structure can reduce the vertical seismic response.

According to the present invention, there is provided an overhead crane traveling on a traveling rail at an upper end of a runway girder disposed on a building frame, wherein a vertical damping member having a damper and a slider containing a viscous fluid is fixed to the crane girder. At the same time, a slider support plate is provided at the end of the building frame supporting the runway girder in the traveling direction of the overhead crane, the slider is disposed so as to be slidable with respect to the slider support plate, and rolling elements are incorporated on the sliding surface of the slider. It is characterized in that the vertical crane response of the overhead crane can be reduced and the slider can smoothly slide when the overhead crane moves.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing an outline of a ceiling crane of the present invention. A crane girder 1 is arranged via traveling wheels 3 on a traveling rail 4 fixed to an upper end of a runway girder 5 arranged in pairs on both sides of an upper part of a building frame 10, and the crane girder is arranged along the traveling rail 4. 1 can run.

A crane girder 1 is provided with a derailment preventing lug 2 so that the overhead crane does not fall during an earthquake.
A vertical damping member 6 having a damper 7 containing a viscous fluid 12 and a slider 8 is fixed to the crane girder 1, and a slider support plate 9 is provided on an end of a building frame 10 supporting the runway girder 5 in the traveling direction of the overhead crane. Is provided. The slider 8 is arranged so as to be slidable with respect to the slider support plate 9 fixed to the building frame 10.

Since the vertical damping member 6 has a sliding structure with the building frame 10, it does not hinder the normal traveling of the crane girder 1 accompanying the movement of the traveling wheel 3, and the vertical damping member 6 is protected against a vertical earthquake. The structure is such that the damping effect of the damper 7 reduces the seismic load of the ceiling crane.

FIGS. 2A and 2B are sectional views showing an example of the vertical damping member 6 of the present invention. Vertical damping member 6
Has an upper end fixed to the crane girder 1 so as not to interfere with the derailment preventing lug 2, and a U-shaped slider 8 is attached to the lower end.

The slider 8 is arranged on a slider support plate 9 provided at the end of the building frame 10 in the traveling direction of the overhead crane so as to be slidable in the traveling direction of the overhead crane via a rolling element 11 such as a ball bearing. .

For this reason, the crane girder 1 and the vertical damping member 6 can move integrally with the traveling of the ceiling crane, but can support the vertical movement. A damper 7 having a piston structure containing a viscous fluid 12 is disposed in the middle of the vertical damping member 6, and the vertical relative displacement accompanying the lifting of the ceiling crane is transmitted to a movable portion 13 in the damper 7,
The resistance of the viscous fluid 12 is generated by the vertical movement of.

The slider 8 attached to the lower end of the vertical damping member 6 becomes free to move via a rolling element 11 such as a ball bearing on a slider support plate 9 provided at the end of the building frame 10 in the traveling direction of the overhead crane. With this arrangement, the crane girder 1 can travel without being obstructed by the slider support plate 9.

Even if the slider support plate 9 is laid so as to have a slight difference in height, since the damper 7 disposed in the middle of the vertical damping member 6 has a piston structure, the slider support plate 9 and the crane The gap difference between the girder 1 and the girder 1 can be absorbed. Therefore, the slider 8 and the slider support plate 9 are not locked, and there is no hindrance to the traveling of the overhead crane.

The vertical damping member 6 has a structure in which the upper end is fixed to the crane girder 1 and the lower end is supported by a U-shaped slider on a slider support plate provided on the building frame 10 to move vertically. Therefore, when a lifting force is generated on the crane girder 1 by a large earthquake having a large vertical seismic force, the force is transmitted to the damper 7 of the vertical damping member 6.

At this time, the vertical displacement of the crane girder 1 with respect to the building frame 10 and the moving amount of the movable portion 13 in the damper 7 of the vertical damping member 6 fixed to the crane girder 1 become the same. Due to the vertical movement, a resistance force is generated in the viscous fluid 12 sealed in the damper 7, and the response of the crane girder 1 to a vertical earthquake is reduced.

As described above, the vertical damping member 6 during an earthquake
By applying the resistance force of the viscous fluid 12 sealed in the damper 7 to the crane girder 1, the vertical response of the crane girder 1 due to the earthquake is reduced. By adjusting the number of the vertical damping members 6 and the capacity of the damper 7 and the vertical gap between the derailment prevention lug 2 and the runway girder according to the assumed magnitude of the seismic force, the response of the overhead crane to vertical earthquakes is minimized. Thus, the function of preventing the ceiling crane from falling to the floor can be improved.

[0024]

According to the ceiling crane according to the first and second aspects of the present invention, a vertical damping member having a damper and a slider containing a viscous fluid is fixed to the crane girder, and the crane girder is supported at an end of a building frame supporting the runway girder. The structure in which the slider is arranged so as to be slidable with respect to the provided slider support plate reduces the response of the overhead crane to vertical earthquakes and improves the function of the overhead crane to prevent it from falling to the floor. it can.

Further, according to the overhead crane according to the second aspect of the present invention, by further incorporating a rolling element on the sliding surface of the slider, the sliding of the slider during the movement of the ceiling crane can be further improved. it can.

[Brief description of the drawings]

FIG. 1 is a side view showing an outline of a ceiling crane of the present invention.

2A and 2B are diagrams showing an example of a vertical damping member of a ceiling crane according to the present invention, wherein FIG. 2A is a longitudinal sectional view of the vertical damping member of FIG. 1, and FIG. 3 is a sectional view taken along the line AA of FIG.

FIG. 3 is a schematic view of a conventional overhead crane of a reactor building.

FIG. 4 is a schematic view of a derailment prevention lug of a conventional overhead crane of a reactor building.

FIG. 5 is a schematic view of a conventional example of a seismic isolation device for a ceiling crane.

[Description of Signs] 1 ... Crane girder, 2 ... Derailment prevention lug, 3 ... Running wheel, 4 ... Running rail, 5 ... Runway girder, 6 ... Vertical damping member, 7 ... Damper, 8 ... Slider, 9 ... Slider support Plate: 10: building frame, 11: rolling element, 12: viscous fluid, 13: movable part, 14: wheel frame, 15: shroud case, 16: resistance plate.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoki Fukushi 3-2-1, Sachimachi, Hitachi, Ibaraki Prefecture Inside Hitachi Engineering Co., Ltd. (72) Inventor Satoshi Suzuki 3-2-2, Sachimachi, Hitachi, Ibaraki No. 1 Hitachi Engineering Co., Ltd. F term (reference) 3F203 DA01 EA00 3F204 AA02 CA05 FC10

Claims (2)

[Claims] An overhead crane traveling on a traveling rail provided at an upper end of a runway girder disposed on a building frame, wherein a vertical damping member having a damper and a slider containing a viscous fluid is fixed to the crane girder. An overhead crane characterized in that a slider support plate is provided at the end of a building supporting the runway girder in the traveling direction of the overhead crane, and the slider is slidable in the traveling direction of the overhead crane with respect to the slider support plate. . 2. An overhead crane traveling on a traveling rail provided at an upper end of a runway girder disposed on a building frame, wherein a vertical damping member having a damper and a slider containing a viscous fluid is fixed to the crane girder. At the end of the building supporting the runway girder, a slider support plate is provided in the traveling direction of the overhead crane, and the slider is arranged so as to be slidable in the traveling direction of the overhead crane with respect to the slider support plate. An overhead crane characterized by incorporating moving objects.