JP3849162B2 - Overhead traveling crane - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an overhead crane that is installed on the ceiling of a structure such as a factory or a reactor building and performs indoor cargo handling.
[0002]
[Prior art]
Generally, as an overhead crane for carrying out cargo handling indoors such as a factory, many cranes having a structure as shown in FIGS. 6 and 7 are employed.
[0003]
As shown in the figure, this overhead crane is constructed such that a girder 2 having a rectangular shape is bridged between a pair of rails 1 and 1 fixed in the vicinity of an indoor ceiling via a traveling wheel 3, and further this girder 2. Further, a trolley 5 provided with a lifting hook 4 is movably provided, and the girder 2 is illustrated by driving the running wheels 3 and 3 at both ends thereof by driving means (not shown) provided on the girder 2 side. 7, the trolley 5 provided on the girder 2 is moved along the girder 2 in the Y direction in FIG. 7, so that the position of the lifting hook 4 is formed between the rails 1 and 1. It can be moved to any position on the plane.
[0004]
[Problems to be solved by the invention]
By the way, as mentioned above, since the girder 2 constituting this overhead crane is supported by only the traveling wheels 3 at both ends thereof riding on the rails 1, 1, large vertical shaking due to vertical earthquake motions. When the response is increased, the damping ratio in the vertical direction is small. Therefore, as shown in FIG. 8, the central portion thereof is greatly bent in the vertical direction, and the traveling wheel 3 is lifted from the rails 1 and 1 with this momentum, and the wheel is removed. There is a risk of it. For this reason, it is conceivable to attach clamps or hooks (not shown) for preventing detachment to both ends of the girder 2, but then excessive stress is applied to the clamps, hooks and rails due to the vertical swing of the girder 2, It is conceivable that the fixed part is damaged.
[0005]
Therefore, the present invention has been devised in order to effectively solve such problems, and its purpose is to suppress vertical deformation of the girder due to vertical vibration of the girder during vertical ground vibration. Thus, the present invention provides a novel overhead crane that can prevent the wheel from lifting from the rail.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention lays an internal hollow girder on a rail fixed to a ceiling at a predetermined interval so that the girder can run freely, and the girder is spaced apart in the longitudinal direction of the girder. providing a plurality of partition plates, the respective partition plates, as well as interposed a damper so that connecting the upper portions of the partition plate, interposed a damper so as to connect the lower portions of the partition plate, said these dampers It is arranged parallel to the longitudinal direction of the girder .
[0007]
This increases the damping ratio of the crane, suppresses vertical deflection, i.e., deformation of the girder during vertical ground vibration, reduces the vertical amplitude, and prevents lifting from the girder rail .
[0008]
The damper includes a nozzle member formed so as to fix one end of a metal bellows filled with a viscous fluid to one partition plate side, and to narrow a flow path of the viscous fluid in the middle of the metal bellows. It may be configured to be fixed to the other partition plate side.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, a preferred embodiment for carrying out the present invention will be described.
[0010]
FIG. 1 shows an embodiment of an overhead crane according to the present invention. In the figure, reference numerals 1 and 1 denote rails fixed on runway girders A and A projecting on both wall surfaces near the ceiling. , 1 is an overhead crane girder 3 and 1 is a traveling wheel that is provided on both ends of the overhead crane girder 2 and travels on rails 1 and 1.
[0011]
As shown in FIG. 7, this overhead crane girder 2 is formed in a planar rectangular shape in which both ends of two vertical beams 2a, 2a positioned in parallel are connected by horizontal beams 2b, 2b. As shown in FIG. 2, the inside of 2a and 2a is hollow inside so that an operator etc. can pass at the time of a maintenance check etc. while lightening. Further, a plurality of partition plates 6, 6... For partitioning the inside along the length direction are provided in the inside, and dampers 7, 4 are respectively provided at four corners between the partition plates 6, 6. 7, 7, 7 are provided. In addition, an opening 6a is formed at the center of each of the partition plates 6 ..., and as described above, an operator or the like in the vertical beam 2a can reduce the length of the vertical beam 2a during maintenance and inspection. You can pass through. Further, S in FIG. 1 is a reinforcing member for reinforcing the partition plates 6 and 6 located at both ends.
[0012]
This bellows damper 7 has been developed as a large-diameter pipe / equipment damping member for nuclear facilities, etc. as shown in FIG. 3, has no mechanical gap, and is capable of damping minute amplitude vibrations with an amplitude of 1 mm or less. It has the feature that a large damping force can be obtained by selecting the nozzle shape.
[0013]
That is, as shown in FIG. 4, the bellows damper 7 is provided between a pair of rod bodies 8 and 8 positioned so that one end is fixed to the partition plates 6 and 6 and the other end is opposed. A pair of flanges 9, 9 fixed to the other end side of the rod bodies 8, 8, a telescopic metal bellows 10 provided on one flange 9 side, and a flange 9 side on the other flange 9 side. The nozzle member 11 is provided. A viscous fluid 12 is sealed in the metal bellows 10, and the viscous fluid 12 is located at the center of the metal bellows 10 when the distance between the flanges 9 and 9 changes due to vibration. Then, the rod body 8, 8, that is, the partition plates 6, 6 to which the rod body 8, 8 is fixed is given a damping action by the resistance at this time. Therefore, as described above, the bellows damper 7 has an extremely small mechanical gap as compared with a mechanical damper (not shown) used as a conventional vibration damping device, so that a minute amplitude vibration having an amplitude of 1 mm or less is also generated. Vibration can be controlled and a large damping force can be obtained by appropriately selecting the viscous fluid and the nozzle shape. The applicants have already filed many applications for the invention relating to the bellows damper 7 (Japanese Patent Application No. 5-175535, etc.).
[0014]
Then, vertical vibration is applied to the overhead crane girder 2 in which the bellows damper 7 is provided between the partition plates 6 and 6 as described above, and the overhead crane girder 2 is bent upward in the vertical direction as shown in FIG. In other words, when a tensile load is applied to each bellows damper 7 located above the interior of the overhead crane girder 2, a compressive load is applied to each bellows damper 7 located below the interior of the overhead crane girder 2. ) When the overhead crane girder 2 is bent downward in the vertical direction, compression and tensile load are applied to the opposite bellows damper 7 (see FIG. 9). Since it is effectively absorbed by the bellows damper 7, a large damping force is obtained, and vertical vibration is effectively suppressed. become.
[0015]
In order to make the explanation easy to understand, the movement of the bellows damper 7 accompanying the bending of the overhead crane girder 2 is greatly expressed in the drawings, but it goes without saying that the movement is actually a small movement.
[0016]
In the embodiment of the present invention, a total of four bellows dampers 7, 7, 7, 7 are provided at four corners in one section of the overhead crane girder 2 partitioned by the partition plates 6, 6. The number of installations is not limited to the present embodiment, and the number and positions of the installations are appropriately changed depending on the length of the overhead crane girder 2, the magnitude of the vertical vibration considered, the damping force of the bellows damper 7 to be used, and the like. Of course. Further, the bellows damper used in the present invention is not limited to the above-described one, and a structure such as Japanese Patent Application No. 5-175535 filed earlier by the present applicant may be used .
[0017]
As described above, the bellows damper used in the present invention has a function of damping a minute amplitude vibration that cannot be suppressed by a conventional vibration damping device, and has been confirmed to be effective even for a vibration having an amplitude of 1 mm or less. . In addition, it uses the viscous resistance of the fluid and has a linear damping characteristic. The present invention uses this bellows damper in order to prevent the overhead crane from lifting due to vertical ground vibration, and it has been found that a bellows damper having a large damping capacity is required .
[0018]
【The invention's effect】
In short, according to the present invention, since the bellows damper is provided in the overhead crane girder, the damping ratio of the overhead crane is increased, the vertical deformation of the girder during vertical ground vibration is suppressed, and the vertical amplitude is reduced. It becomes smaller and prevents it from lifting from the rails of the overhead crane girder .
[Brief description of the drawings]
FIG. 1 is a side view showing an embodiment of an overhead crane according to the present invention.
FIG. 2 is a cross-sectional view taken along the line BB in FIG.
FIG. 3 is an explanatory view showing a conventional use example of a bellows damper.
FIG. 4 is a cross-sectional view showing a configuration of a bellows damper.
FIG. 5 is a model diagram showing the movement of the bellows damper when the overhead crane girder is bent in the vertical direction.
FIG. 6 is a simplified diagram showing the configuration of a conventional overhead crane.
FIG. 7 is a view taken in the direction of arrows AA in FIG.
FIG. 8 is a conceptual diagram showing a state of shaking of an overhead crane girder when vertical shaking is applied to a conventional overhead crane.
FIG. 9 is a conceptual diagram showing moment and distortion generated in an overhead crane girder.
[Explanation of symbols]
1 Rail 2 Overhead Crane Girder 2a Longitudinal Beam 2b Lateral Beam 3 Traveling Wheel 6 Partition Plate 7 Bellows Damper
11 Nozzle member

Claims (2)

A rail which is fixed at a predetermined distance on a ceiling, hung freely travel inside hollow girders, the interior of the girder, plurality of partition plates spaced apart in the longitudinal direction of the girders, the respective partition plates The dampers are interposed so as to connect the upper parts of the partition plates, and the dampers are interposed so as to connect the lower parts of the partition plates, and these dampers are arranged in parallel to the longitudinal direction of the girder. And overhead crane. The damper includes a nozzle member formed so as to fix one end of a metal bellows filled with a viscous fluid to one partition plate side, and to narrow a flow path of the viscous fluid in the middle of the metal bellows. The overhead crane according to claim 1, wherein the overhead crane is fixed to the other partition plate side .

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