JP3565294B2 - Crane vibration control structure - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a vibration control structure of a crane, and more particularly to a vibration control structure of a crane using a machine room as a vibration control structure.
[0002]
[Prior art]
The legally designed load of the crane against an earthquake is 0.2 G in the horizontal direction, so that it can withstand a horizontal force of 0.2 times its own weight in the horizontal direction.
Japanese Patent Application Laid-Open No. 55-101588 discloses a technique in which a trolley is provided with a girder rail clamping mechanism so that the trolley is fixed to the girder during an earthquake.
[0003]
[Problems to be solved by the invention]
However, if a horizontal force exceeding 0.2 G is applied during an earthquake, the crane may be damaged or collapsed. Further, even if the trolley is fixed to the girder at the time of the earthquake, if a horizontal force exceeding 0.2 G is applied, damage or collapse cannot be prevented. For this reason, it is necessary to provide a vibration damping device for suppressing the shaking of the crane due to the earthquake, but it requires a considerable weight and space.
[0004]
The present invention has been made in view of the above problems, and has as its object to provide a crane vibration control structure using an existing machine room as a vibration control device.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, in the invention of claim 1, a support means for supporting a machine room of the crane movably in the front-rear direction of the crane, and one end of one side of the machine room is joined in the front-rear direction, A first buffer block, the other end of which is joined to a first support member fixed to the crane, and a second support member, one end of which is joined to the other side of the machine room in the front-rear direction and fixed to the crane A second buffer block, the other end of which is joined to
Each of the first buffer block and the second buffer block includes a pair of opposed end plates, a spring and a damper provided between the end plates in the front-rear direction of the crane, and a crane that connects the end plates to each other. And a breaking member for cutting with a predetermined horizontal force in the front-rear direction.
[0006]
In the invention of claim 2, the breaking member is joined to the end plate by a pin, and the pin is cut by a predetermined horizontal force.
[0007]
[Action]
According to the invention of claim 1, the machine room of the crane is supported so as to be movable in the front-rear direction of the crane, but one end of the first buffer block is joined to one side of the machine room in the front-rear direction, and is fixed to the crane. The other end of the first buffer block is joined to the first support member. Similarly, one end of the second buffer block is joined to the other side of the machine room in the front-rear direction, and the other end of the second buffer block is joined to the second support member fixed to the crane. As a result, the machine room is normally fixed to the crane and functions normally as the machine room. When a force exceeding a predetermined horizontal force acts in the longitudinal direction of the crane, the breaking member is cut, and each of the first buffer block and the second buffer block is configured by a spring and a damper. Since the horizontal force from the crane is no longer transmitted, it is almost stationary, and the relative movement with the crane becomes intense. Since the spring and the damper work to absorb the relative movement, the vibration and damping of the crane due to the earthquake are damped. If the predetermined horizontal force is a value slightly exceeding 0.2 G of the design load of the crane, the structure will be able to withstand the seismic horizontal force in the longitudinal direction of the crane even if it exceeds 0.2 G.
[0008]
According to the second aspect of the present invention, the breaking member is joined to the end plate by a pin, and the pin is cut by a predetermined horizontal force, so that the reliability of the cutting increases.
[0009]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a container crane having a machine room according to the present embodiment, and FIG. 2 is a diagram illustrating a support structure of the machine room. Container cranes are installed on the quay and mount containers on ships that berth and lift containers from ships. A sea leg 2 having wheels 1 running on a quay and a land leg 3 also having wheels 1 are connected by a portal 4 and diagonal members 5. A girder 6 is connected to the tops of the marine leg 2 and the land leg 3, and an upper member 7 is further provided at the top of the marine leg 2 and is supported by a diagonal member 5. A boom 8 is connected to a tip of the girder 6 by a hinge (not shown), and is horizontally supported by a tension bar 9. A sheave 10 is provided at the tip of the boom 8 and the upper member 7, and the boom 8 is raised and lowered by a wire 11 for raising and lowering. The hoisting wire 11 is unwound and unwound by the hoisting device 12 to raise and lower the boom 8. The machine room 13 is provided on the girder 6 and houses the undulating device 12 and the like. A rail (not shown) is provided below the girder 6 and the boom 8, and the trolley 14 moves on the rail. The trolley 14 is provided with a spreader 15 for lifting and suspending the container and an operator's cab 16 for operating the trolley 14.
[0010]
FIG. 2A shows a structure for attaching the machine room 13 to the girder 6, and FIG. 2B shows a structure of the buffer block 20. Wheels 18 that move in the front-rear direction of the crane are provided at the lower part of the machine room 13, and have a structure that can move on rails 19 provided on the girder 6. One end of the machine chamber 13 is joined to a support member 21a fixed to the girder 6 via a buffer block 20, and the other end is joined to a support member 21b fixed to the girder 6 via the buffer block 20.
[0011]
In FIG. 2 (B), a buffer block 20 includes an end plate 22 disposed opposite thereto, a spring 23 and a damper 24 provided therebetween and fixed to the end plate 22, and a breaking member 25 for joining the end plate 22. Consists of The breaking member 25 is attached to the end plate 22 with a pin 26. When the horizontal force of the earthquake exceeds 0.2 G and in the longitudinal direction of the crane (the direction of the girder 6), the pin 26 is cut so that the breaking member 25 comes off.
[0012]
Next, the operation of the machine room during an earthquake will be described.
When the horizontal force of the earthquake is 0.2 G or less, the pins 26 are not damaged, and the machine room 13 vibrates integrally with the girder 6, but the crane structure can withstand this horizontal force. There is no particular problem. When the horizontal force of the earthquake exceeds 0.2 G and is in the front-rear direction of the crane (the direction of the girder 6), the pin 26 is cut off, the breaking member 25 comes off, and the spring 23 and the damper 24 operate. In this case, the machine room 13 loses the restraining force from the girder 6 and hardly moves, but the girder 6 moves horizontally and violently due to the seismic force. When viewed from the girder 6 side, the machine room 13 relatively moves in the direction opposite to the girder 6 within the allowable range of the spring 23 and the damper 24 on the rail 19 via the wheel 18, and the spring 23 and the damper 24 Since it works so as to absorb the relative motion, it absorbs the vibration of the crane and attenuates the run-out.
[0013]
The present invention has a vibration damping structure effective against horizontal forces in the longitudinal direction of a crane that is relatively vulnerable to earthquakes, but by providing a buffer block that can move the machine room in the transverse direction and operate in the transverse direction, An effective vibration damping structure can be provided for horizontal force in the transverse direction.
[0014]
【The invention's effect】
As is clear from the above description, the present invention makes it possible to move the machine room in the longitudinal direction of the crane, join the machine room to the crane structure via the buffer block in the longitudinal direction of the crane, and connect the buffer block in the longitudinal direction of the crane. In this case, the spring and the damper operate at a predetermined horizontal force or more, and the spring and the damper operate when the horizontal force of the earthquake exceeds a design value, so that the vibration of the crane is absorbed and damped. Further, since the machine room itself is used as a vibration damping device, there is no need for any other special device or additional weight.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a container crane provided with a machine room according to an embodiment of the present invention.
FIG. 2 is a diagram showing a structure for supporting a machine room and a structure of a buffer block.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wheel 2 Sea leg 3 Land leg 6 Girder 7 Upper member 8 Boom 10 Sheave 11 Undulating wire 12 Undulating device 13 Machine room 14 Trolley 15 Spreader 16 Operator's cab 18 Wheels (support means)
19 rails (supporting means)
Reference Signs List 20 buffer blocks 21a, 21b support member 22 end plate 23 spring 24 damper 25 breaking member 26 pin

Claims (2)

Support means for supporting a machine room of the crane movably in the front-rear direction of the crane , one end of which is joined to the one side of the machine room in the front-rear direction and the other end of which is connected to a first support member fixed to the crane; The joined first buffer block and the second buffer block having one end joined to the other side of the machine room in the front-rear direction and the other end joined to a second support member fixed to a crane. Prepare,
Each of the first buffer block and the second buffer block includes a pair of opposed end plates, a spring and a damper provided between the end plates in the front-rear direction of the crane, and a crane that connects the end plates to each other. A breaking member for cutting with a predetermined horizontal force in the front-rear direction of the crane. The vibration damping structure for a crane according to claim 1, wherein the breaking member is joined to the end plate by a pin, and the pin is cut by a predetermined horizontal force.

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