JPH06100010B2 - Free access floor anti-vibration frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention provides a steel frame composed of a beam steel frame and a column steel frame on a body floor of a building, and forms a walking floor surface on the steel frame. The present invention relates to a so-called steel frame type free access floor vibration-isolating frame structure having a double floor structure.

[Prior Art] For example, in a clean room such as a semiconductor manufacturing facility or a computer room, a double-floor structure is usually adopted, and the underfloor is used as a return duct, various wiring, and other equipment piping space. As such a double floor structure, the above-mentioned steel frame type free access floor is adopted.

However, a steel frame type free access floor generally has a large amount of vibration, and even in a relatively quiet state such as at the time of completion of construction, it is common that the amount of vibration is about 3 to 5 times that of the building floor. For this reason, when installing precision equipment such as semiconductor manufacturing equipment that must avoid even slight vibrations, in the past, it was separated from the free access floor at the position where the precision equipment of the body floor designed for vibration isolation should be installed. They built the RC mechanical foundation (so-called stone table) and installed precision equipment on it.

[Problems to be solved by the invention]

In the above conventional example, not only the piping such as the return duct to the underfloor air is restricted due to the mechanical foundation, but also a new mechanical foundation is required when changing the layout of the production line or precision equipment, and the vibration isolation design However, there is a drawback in that it is not possible to make full use of the structure of the building floor.

In particular, in the case of a clean room, a large amount of suspended dust is generated due to the additional construction of the mechanical foundation accompanying the changes in the layout of the production line and precision equipment, etc.Therefore, until the air is purified to the original clean state, several It will take months, and the production will be interrupted for a long time.

By the way, in a steel frame type free access floor, the smaller the grid composed of pillar steel frames, that is, the more the number of pillar steel frames used and the shorter the span of the beam steel frame, the more the generation and propagation of vibration can be suppressed. , It is also known that the restrictions on the loading weight on free access floors can be relaxed.

Therefore, as a solution to the above-mentioned conventional defects, increasing the number of pillar steel frames is considered first, but if the number of pillar steel frames is large, the workability becomes poor and the construction cost increases,
Moreover, the underfloor space is subject to considerable restrictions due to the large number of columns.

Second, the grid composed of pillar steel frames should be set large, and only in the zones where you want to suppress vibration, jack type moving columns are erected between the pillar steel frames to support the beam steel frames. It is conceivable to shorten the span of the steel frame and suppress the generation and propagation of vibration.

However, in this case, even if a plurality of jack type movable columns are installed between the column steel frames, when one of the jack type movable columns is extended and the beam steel frame is pushed up, the remaining jack type movable columns are The effect of pushing up by will be lost.

Therefore, in practice, only one jack type movable column can be installed between the column steel frames, and therefore the grid constituted by the column steel frames cannot be set too large. That is, in order to obtain a span (the minimum span of the beam steel frame specified by the target vibration amount) that provides a desired vibration amount by installing one jack type movable column at an intermediate position between the column steel frames. Must be set in advance in a grid such that the span of the beam steel frame (the interval between the column steel frames) is twice the minimum span.

Therefore, merely using the jack type movable column cannot provide a sufficient solution to the above-mentioned conventional drawbacks because the number of column steel frames used is large.

The present invention has been made based on the above consideration results, in a steel frame type free access floor, while setting a large grid composed of pillar steel frames, only an arbitrary zone in which vibration is desired to be suppressed is arbitrary. The purpose is to be able to control the vibration characteristics.

[Means for solving problems]

The technical means taken by the present invention to achieve the above object are as follows. That is, the anti-vibration structure of the free access floor according to the present invention, in the steel frame type free access floor described at the beginning, between the beam steel frame and the skeleton floor, a jack type movable column for introducing a compressive force and a tensile force. It is characterized in that the jack type movable columns to be introduced are erected alternately.

[Action]

According to the above configuration, the jack type movable column that introduces the compressive force, that is, the jack type movable column that extends and acts on the side that pushes up the beam steel frame, and the jack type movable column that introduces the tensile force, that is, the beam that is reduced in size. Since the jack type movable columns that act on the side where the steel frame is pulled down are alternately erected, all the jack type movable columns effectively work to support the beam steel frame.

Therefore, it is possible to install an arbitrary number of jack type movable columns between the column steel frames in an arbitrary zone and arbitrarily set the minimum span of the beam steel frames.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 is a schematic vertical cross-sectional view of a vibration isolation frame for a free access floor used in clean rooms of semiconductor manufacturing facilities.
FIG. 2 is a schematic plan view of the vibration-isolating frame structure of the free access floor, FIG. 3 is a side view with a part notched to explain the column-beam joint portion, and FIG. 4 is a plan view of the column-beam joint portion, FIG. 5 is a side view of a main part of the vibration-isolating frame structure of the free access floor, and FIG. 6 is an exploded perspective view of the main part. FIG. 7 is a schematic plan view for explaining a case of changing a zone having a high image stabilization level.

In the figure, reference numeral 1 is a building floor of a building that is designed to prevent vibration.
2 is a walking frame with a floor panel such as a grating plate 5 laid on a steel frame made up of beam steel frames 3 forming the large beams 3a and small beams 3b and column steel frames 4 supporting the large beams 3a. It is a free access floor that forms a floor surface 6, and the underfloor space is used for piping such as return ducts and wiring. The pillar steel frame 4 is previously processed in a factory or the like,
The lower end is fixed to the building floor 1 by a chemical anchor 7 or the like. The structure of the column-beam joint portion can be set as appropriate, and for example, the upper and lower flanges and the web of the large beam 3a made of H-shaped steel and the column steel frame 4 may be welded, as in the conventional case. In order to improve the performance, the column-beam joint is constructed as follows. That is, as shown in FIG. 3, on the pillar steel frame 4, a horizontal plate 4a for mounting the girders 3a ... And its reinforcing ribs.
4b are welded to each other, and bolt holes 4c are bored in the horizontal plate 4a. Then, with the ends of the girders 3a placed on the horizontal plate 4a, the lower flanges of the girders 3a and the horizontal plate 4a are fixed by bolts and nuts 8 ... In this state, the upper flanges of the girders 3a. Is welded to the top plate portion 4d of the pillar steel frame 4.

Beam-mounting brackets 9 having bolt holes are previously welded to the girder 3a at regular intervals, and the brackets 9 of the girders 3a, which face each other, are fitted with a backing plate 10 and bolts and nuts 11. The small beam 3a is constructed so as to be erected.

In a preferred embodiment of the present invention, in the arbitrary zone A where it is desired to suppress the vibration of the steel frame type free access floor having the above-mentioned structure, as shown in FIGS. 1, the jack type moving column 12 for introducing the compressive force and the jack type moving column 13 for introducing the tensile force
Are alternately erected to suppress the vibration of the zone A and the propagation of the vibration from the surroundings to the zone A.

Although it is possible to adopt various structures as the jack type moving columns 12 and 13, in this embodiment, by operating the handle 14 to rotate the reverse threaded shaft body 15 in one direction. , Both of which have a structure in which the total length is extended and the total length is reduced by rotating in the opposite direction. Further, as shown in FIG. 5, the jack type movable column (the jack type movable column which acts on the side where the beam steel frame 3 is pulled down by contracting) 13 which introduces a tensile force has the upper end attached to the beam steel frame 3 by bolts and nuts 16. Fix with, chemical anchor 7 at the bottom.
Alternatively, it is fixed to the body floor 1 by a fixing means that can be attached and detached as required and has sufficient tensile strength, such as the use of an adhesive. The jack type moving column (the jack type moving column which extends and pushes up the beam steel frame 3) 12 for introducing a compressive force may be simply interposed between the frame floor 1 and the beam steel frame 3, but is not shown in the figure. In the embodiment, for safety, the upper end is fixed to the beam steel frame 3 with bolts and nuts 16 ...

According to the above configuration, the jack type movable column that introduces the compressive force, that is, the jack type movable column 12 that extends and acts on the side that pushes up the beam steel frame 3, and the jack type movable column that introduces the tensile force, that is, the contraction Since the jack type movable columns 13 acting on the side of pulling down the beam steel frame 3 are alternately arranged, all the jack type movable columns 12 and 13 work effectively for supporting the beam steel frame 3.

Therefore, the number of used jack type movable columns 12 and 13 and the arrangement interval can be arbitrarily set according to the target vibration amount.

Therefore, the grid composed of the pillar steel frames 4 ... should be set as large as possible within the range where vibration does not pose a problem for pedestrians, while reducing the number of pillar steel frames 4 ... and the number of column / beam joints. Also, only in the zone A where it is desired to suppress the vibration, the number of the jack type movable columns 12 and 13 to be used and the arrangement interval are arbitrarily set according to the target vibration amount, and the control is performed so as to obtain the desired vibration characteristics. You can

Further, in this embodiment, since a plurality of beam-mounting brackets 9 ... Are welded to the respective girders 3a in advance at regular intervals, it is possible to select and change the installation direction of the beam 3b. . Therefore, in the span adjacent to the zone A where the vibration is desired to be suppressed, as shown in FIG. 2, the crossbeams 3b ... In the adjacent span are not orthogonal to each side of the zone A (in parallel). By constructing the crossbeam 3b ...
Since the transmission of vibration by the beam 3b from the adjacent span to the zone A is eliminated, the vibration isolation effect of the zone A can be further enhanced.

When the zone A is changed to the position A shown in FIG. 7 due to changes in the layout of the production line or precision equipment, for example, the standing positions of the jack type movable columns 12 and 13 are simply changed. Alternatively, by changing the erection direction of the surrounding beam 3b, it is possible to further suppress the vibration propagation from the periphery to the zone A.

The grid constituted by the pillar steel frames 4 ... Can be arbitrarily set, but in this embodiment, it is set to 3.6 m × 3.6 m. The arrangement interval of the brackets 9 ... Is set to 0.6 m. By setting in this way, a high-grade anti-vibration level of 0.6m x 0.6m grid, medium
It is easy to create three types of anti-vibration grades, a 1.8m x 1.8m grid and a 3.6m x 3.6m grid where vibration is not a problem.

〔The invention's effect〕

Since the present invention has the above-mentioned configuration, the following effects can be obtained.

That is, a jack type moving column that introduces a compressive force, that is, a jack type moving column that extends and acts on the side that pushes up the beam steel frame, and a jack type moving column that introduces a tensile force, that is, a side that shrinks and pulls down the beam steel frame. Since the working jack type moving columns are alternately erected, all the jack type moving columns work effectively for supporting the beam steel frame.

Therefore, it is possible to install an arbitrary number of jack type moving columns between the column steel frames in any zone, and to set the minimum span of the beam steel frame arbitrarily, and therefore make the grid composed of the column steel frames as large as possible. Set the number of columns to be used, and reduce the number of column steel beams and the number of column-beam joints. It can be arbitrarily set and controlled so as to obtain a desired vibration characteristic.

[Brief description of drawings]

1 to 6 show an embodiment of the present invention, FIG. 1 is a schematic vertical cross-sectional view of a vibration isolation frame for a free access floor, and FIG. 2 is a schematic plan view of a vibration isolation frame for a free access floor. FIG. 3 is a partially cutaway side view for explaining the column-beam joint portion, FIG. 4 is a plan view of the column-beam joint portion, and FIG. 5 is a side view of a main part of the vibration-isolating frame structure of the free access floor. FIG. 6 is an exploded perspective view of a main part, and FIG. 7 is a schematic plan view for explaining a case of changing a zone having a high image stabilization level. 1 ... Physical floor, 2 ... Free access floor, 3 ...
Beam steel frame, 4 …… Column steel frame, 6 …… Walking floor, 12,13 …… Jack type moving column.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuyoshi Murai No. 3-8, Mokudo, Mihara-cho, Minamikawachi-gun, Osaka Prefecture Takenaka Corporation Technical Research Institute Osaka Branch

Claims (1)

[Claims] 1. A steel frame free access floor in which a steel frame composed of a beam steel frame and a column steel frame is provided on a frame floor of a building, and a walking floor surface is formed on the steel frame, and the beam steel frame and the frame floor are provided. A vibration isolation frame structure for a free access floor, characterized in that a jack type movable column for introducing a compressive force and a jack type movable column for introducing a tensile force are erected alternately between the two.