Clean room air system

• US 5,014,608 A
• Filed: 08/17/1990
• Issued: 05/14/1991
• Est. Priority Date: 04/27/1989
• Status: Expired due to Fees

• Current Assignee: Sinko Kogyo Co., Ltd.
• Original Assignee: BROD & Mcclung--Pace Company
• Inventors: Benson, David E., Post, Michael T.
• Primary Examiner(s): Joyce, Harold
• Application Number:
  US07/569,234
• Time in Patent Office: 270 Days
• Field of Search: 98/31.5, 98/31.6, 98/33.1, 98/34.5, 98/34.6, 98/36, 98/40.11, 98/41.3, 98/115.3, 98/115.1, 55/382.2, 55/484, 55/467
• US Class Current: 454/187
• CPC Class Codes: F24F 3/167 Clean rooms, i.e. enclosed spaces in which a uniform flow of filtered air is distributed air distribution by perforated walls F24F7/10

Abstract

A clean room is supplied with air at a controllable velocity from a blower with a variable damper mechanism. The ceiling of the clean room is comprised of a plurality of panels of particulate filter material. Associated with at least some of said panels are air dampers comprised of first and second adjacent perforated plates. The first plate is fixed and the second plate is mounted for translational movement relative to the first. By moving the second plate relative to the first, the perforations therein are selectably opened or occluded, permitting the air passing through each panel to be regulated. Air flow through the room as a whole is controlled by the variable air flow feature of the blower.

Claims

1. A ventilation system for a clean room comprising:

a centrifugal blower, said blower including a rotary bladed wheel having an axis of rotation, a baffle in the form of a surface of rotation concentrically disposed relative to said axis for permitting the volume of air moved by said blower to be controlled, and means permitting telescopic movement of the baffle relative to the wheel to vary the volume of air moved by said blower;

a plenum through which air can move from the blower to an area above the room;

a suspended ceiling separating the plenum and the room, said ceiling being comprised of a plurality of panels that each includes a particulate filter and an adjustable baffle for controlling the rate of air flow therethrough, the baffles being each individually controllable to establish a desired ratio between the air flows through the panels; and

said baffle in the centrifugal blower being controllable independently of the baffles in the panels to permit a localized change in clean room air flow by controlling one or more of the panel baffles, and to permit a generalized change in clean room air flow by controlling the blower baffle.

2. In a ventilation system for a clean room, said system including an air filtration system having a frame, an air filter, and an air valve comprised of first and second perforated plates positioned adjacent one another and mounted for slidable movement therebetween, an improvement wherein said air filter is segregated into first and second sections received into a lower portion of said frame and separated by a central bracket to which is attached a worm drive assembly, said assembly including a member extending upwardly coupling to the second plate to control the position thereof, said assembly further including a shaft extending downwardly through the bracket into a hollow defined by said bracket, said hollow being sealed below but having an opening through which the shaft can be accessed and turned, said opening normally being plugged by a plug.

3. The invention of claim 2 in which the first and second plates each have a central region that is unperforated.

4. The invention of claim 2 in which the second perforated plate is mounted for slidable movement beneath the first.

5. A method for controlling the air flow in a clean room, the method comprising the steps:

blowing air from a blower into a plenum;

passing said air through air filter panels comprising the ceiling of the clean room; and

controlling the rate of air flow to the room as a whole with a first control and controlling the rate of air flow through each of the individual ceiling panels with a plurality of second controls.