JPH0413552Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an air blowing structure for a clean room that can correct the turbulence of airflow and form a laminar flow in a hydrodynamic sense.

[Conventional technology]

Vertical laminar flow clean rooms, clean tunnels, clean benches, etc. are well known as technologies for creating clean spaces. In this specification, these clean spaces will be collectively referred to as clean rooms, but in the vertical laminar flow clean rooms known so far, the area of the HEPA filter is It blows out air uniformly toward the suction surface on the floor, which is substantially equivalent to Suction was considered to be an important element in forming laminar flow.

[Problem that the invention attempts to solve]

Conventional vertical laminar flow clean rooms have the following problems that cause turbulence in the flow. Conventional HEPA filters that form the blowout surface are usually made up of a continuous medium with a meandering surface, so from a microscopic perspective, the blowout speed varies at the peaks and valleys, which affects the flow. This will cause disturbance. Furthermore, when HEPA filters are spread over a large area, it is common to form a filter surface by adjoining a large number of small-area HEPA filter units. A frame (ceiling frame) with grids is used, but since this frame is exposed to the air blowing surface, vortices are generated in this frame part, causing disturbance of the laminar flow. Furthermore, if there are lighting fixtures or various measuring instruments on the ceiling surface, they will also disturb the flow.

The present invention aims to correct the flow turbulence in such a conventional vertical laminar flow clean room and easily form a true laminar flow in a hydrodynamic sense.

[Means to solve problems]

The present invention is a clean room air filter in which a porous fluid regulating layer is installed on the side of the air blowing surface of a filter stretched over a plane, with a predetermined distance from the air blowing surface and substantially parallel to the air blowing surface. In the blowout structure, a mesh, cloth, or similar breathable membrane is used as the porous fluid regulating layer, and this breathable membrane is spread flat on a grid, louver, or similar open plate-like body. By blowing air out through this breathable membrane, the turbulence of the blowout flow described above is corrected, and a laminar flow is formed in a hydrodynamic sense.

Here, the breathable membrane used in the present invention is a mesh or cloth in which small ventilation holes are formed substantially regularly over the entire surface, such as nets, woven fabrics, or knitted fabrics. For example, a so-called punching board as seen in Japanese Utility Model Application Publication No. 57-132123 is not used. In ordinary porous resin plates where the holes are formed at a pitch of 4 mm or more, a vortex (Karman flow) is formed on the back side of the plate between the holes, causing a hydrodynamic effect. Laminar flow in the sense of the word cannot be formed. To be more precise, the Karman method requires that the thickness of the material existing between the holes forming the ventilation holes (the diameter of the wire in mesh or cloth) be less than 1 mm on average. Necessary to prevent formation. At that time, when the overall ventilation resistance of the porous fluid regulating layer consisting of a mesh or cloth membrane and a grid, louver or similar open plate-like body supporting this membrane is, for example, an average blowing flow velocity of 0.45 m/sec. 1mm
It is desirable that the structure has a ventilation resistance of Aq or more.

In addition, in implementing the present invention, it is necessary to use a long belt-shaped membrane with a predetermined width as a breathable membrane, and to have a planar expanse by connecting the longitudinal side edges of the membrane to each other. It is practical to form the film on a membrane surface of a certain area, and in this case, it is convenient to connect the long membranes using a hanging fitting for hanging the apertured plate-like body from the filter frame. This hanging fitting includes a hanging bolt whose upper end is supported by the filter frame, a hollow tube with a slit-shaped opening on the lower surface that is supported horizontally by the hanging bolt, and a hollow tube that is inserted into the hollow tube. The present invention includes a stopper member made of a rod-shaped body having a diameter larger than that of the slit-shaped opening, and a connector whose upper end is supported by the stopper member and whose lower end is connected to the opening plate-shaped body through the slit-shaped opening. they devised. Thereby, by sandwiching the side edges of the elongated membrane between the stopper member and the slit-like opening of the hollow cylinder, a wide membrane having the required area can be easily formed from the elongated membrane.

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

In FIG. 1, 1 and 2 indicate a vertical frame and a horizontal frame stretched horizontally on the ceiling surface, and the vertical frame 1 and horizontal frame 2 form many squares on the ceiling surface. The HEPA filter unit 3 is set in the opening of this square,
This allows the HEPA filter to be spread across the ceiling. In the present invention, a porous fluid regulating layer is installed on the side of the air blowing surface of this planarly stretched filter at a predetermined distance from the air blowing surface and substantially parallel to the air blowing surface. As this porous fluid regulating layer, one consisting of a mesh, cloth or similar breathable membrane 4 and a grid, louver or similar open plate-like body 5 is used. The apertured plate-like body 5 mainly plays the role of spreading the breathable membrane 4 in a planar manner, but the size of the opening may be any size that can support the membrane 4, and there is no restriction on the diameter. However, it is preferable that the apertures are distributed with normality and that the thickness of the material forming each aperture in the planar direction is 1 mm or less.

Meshes and cloth are generally manufactured as long strips, so in order to cover a large ceiling area with a considerable distance in both the vertical and horizontal directions, it is necessary to cut the required length from the long material in the vertical direction. However, in the horizontal direction, it is necessary to connect the long objects in the width direction. FIG. 1 shows a cross section of a long breathable membrane 4 cut in the width direction, and the upper end is supported by the frame 1 or 2 as a member that connects the width edges of the breathable membrane 4. A hanging bolt 6 and a hollow cylinder 7 having a slit-shaped opening on the lower surface and supported by the hanging bolt 6 in the horizontal direction are used.

FIG. 2 schematically shows a structure in which the width edges of the membrane 4 are joined together using this hanging metal fitting. As seen in Figure 2, this hanging bracket is
At the same time as connecting the edges of the membrane 4, the open plate-like body 5 is suspended. First, a hanging bolt 6 whose upper end is supported by the filter frame 1 or 2 is attached.
The hollow cylinder 7 is suspended horizontally. A slit-shaped opening 8 is provided on the lower surface of the hollow cylinder 7, and a rod-shaped stopper member 9 (with a tapered surface on the lower surface) having a larger diameter than the opening 8 is attached to the hollow cylinder 7.
inserted inside. Then, a connecting tool 10 (for example, a hanging bolt) for suspending the open plate-like body 5 is attached to this stopper member 9. The diameter of the connector 10 for suspending the apertured plate-like body 5 is smaller than that of the slit-shaped opening 8 of the hollow tube 7. Therefore, when the apertured plate-like body 5 is hung, the stopper member 9 is moved by the weight of the apertured plate-like body 5 into the slit-like aperture 8. When the aperture plate member 5 is lifted up, a gap is created between the stopper member 9 and the slit-like aperture 8. When the edge of the breathable membrane 4 is folded (raised) toward the filter and inserted into this gap and the apertured plate 5 is hung, the weight of the apertured plate 5 causes the edge to stop. It is firmly sandwiched between the member 9 and the slit-like opening 8. Therefore, by simultaneously sandwiching the edges of the adjacent gas permeable membranes 4 into the gap, the adjacent gas permeable membranes 4 can be airtightly connected.

In addition, as shown in FIG. 1, at the portion in contact with the side wall of the clean room, the edge of the breathable membrane 4 may be raised up from the side wall 11, and this raised portion may be held down and fixed with a pressing plate 12.

As explained above, according to the present invention,
The presence of a frame frame to support the HEPA filter,
The turbulence of the blown air flow in laminar flow cleanrooms due to the presence of lighting equipment or due to the construction of the HEPA filter media is smoothed out by the permeable membrane, thereby creating a true hydrodynamic laminar flow. can be formed. Furthermore, the installation work of this membrane is extremely simple, and an excellent effect is exhibited in that a sophisticated laminar flow type clean room can be formed at a low equipment cost.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the air blowing structure for a clean room according to the present invention, and FIG. 2 is an assembled diagram of the essential parts of the air blowing equipment for a clean room according to the present invention viewed in perspective. 1, 2...Frame (filter frame), 3...
HEPA filter unit, 4...breathable membrane,
5... Opening plate-like body, 6... Hanging bolt, 7... Hollow tube, 8... Slit-shaped opening, 9... Stopper member, 10... Connector (hanging bolt).

Claims (1)

[Claims for Utility Model Registration] (1) A porous fluid regulating layer is provided on the side of the air blowing surface of a filter that is stretched in a plane, at a predetermined distance from the air blowing surface and substantially parallel to the air blowing surface. In the air blowing structure for a clean room that is installed, a belt-shaped mesh, cloth, or similar breathable elongated membrane having a predetermined width is used as the porous fluid regulating layer, and the longitudinal direction of this elongated membrane is By connecting the side edges along each other, a membrane surface of the required area with a planar expanse is formed, and this membrane surface with a planar expansion is placed on a grid, louver or similar open plate-like body. When connecting the side edges of the long membrane, the side edges are bent toward the filter, and a rod-shaped stopper is suspended between the filter and the porous fluid regulating layer. A clean room air blowing structure characterized by being locked to a member. (2) For breathable membranes, the thickness of the material existing between the holes forming the ventilation holes (in the case of mesh/cloth, the diameter of the wire body) in the plane direction is on average 1 mm or less. The air blowing structure for a clean room according to claim 1, wherein the entire ventilation resistance of the porous fluid regulating layer is 1 mmAq or more when the average blowing flow velocity is 0.45 m/sec. (3) The stopper member is attached to a hanging fitting for hanging the apertured plate-like body from the filter frame.
Air blowing structure for clean rooms as described in section. (4) The hanging fitting consists of a hanging bolt whose upper end is supported by the filter frame, a hollow tube with a slit-shaped opening on the bottom surface supported horizontally by the hanging bolt, and a hollow tube that is inserted into the hollow tube. The stopper member is made of a rod-shaped body having a diameter larger than that of the slit-shaped opening, and a connecting tool whose upper end is supported by the stopper member and whose lower end is connected to the opening plate-shaped body through the slit-shaped opening, and has a long length. The air blowing structure for a clean room according to claim 3, wherein the side edge of the membrane is sandwiched between the stopper member and the slit-shaped opening of the hollow cylinder.