Work station having an air flow controller

• US 6,517,428 B1
• Filed: 11/03/2000
• Issued: 02/11/2003
• Est. Priority Date: 11/05/1999
• Status: Expired due to Term

• Current Assignee: Lab Products, Inc., Polar Controller Incorporated
• Original Assignee: Lab Products, Inc.
• Inventors: Cohen, Adam, Murray, Dale, Tang, Josh, Darby, Thomas, Dietrich, Eric
• Primary Examiner(s): Joyce, Harold
• Application Number:
  US09/705,682
• Time in Patent Office: 830 Days
• Field of Search: 454/49, 454/57, 454/187, 454/230, 454/229, 454/232, 454/233, 119/418, 119/419, 119/452, 119/472, 119/473, 119/500, 553/852, 554/67, 554/73
• US Class Current: 454/56
• CPC Class Codes: A01K 1/031 Cages for laboratory animals; Cages for measuring metabolism of animals
• CPC Class Codes: A01K 13/00 Devices for grooming or caring of animals, e.g. curry-combs; Fetlock rings; Tail-holders as part of the harness B68B5/04; Devices for preventing crib-biting; Washing devices; Protection against weather conditions or insects

Abstract

A work station having an environmental controller for maintaining air flow in and through the work station at a user-selected level. The work station includes a pressure cabinet and a perforated work surface forming the top of the pressure cabinet. A pressure inducing assembly is located within the cabinet below the work surface to draw air into the cabinet and create a negative pressure in a work space defined above the work surface. A support coupled to two sides of the pressure cabinet provides a channel for air flow from the pressure cabinet to an air chamber located above the work surface. Air is drawn from the air chamber generally downward toward the work surface by the negative pressure created in the work space to provide an air curtain substantially surrounding the work surface.

Claims

1. A work station comprising:

a base;

a top cabinet;

a support extending from said base and supporting said top cabinet, an air flow channel through which air may flow being defined through said support and partially through said base and said top cabinet;

a work surface disposed on and forming a top to said base and having perforations along at least a portion thereof;

a pressure inducing assembly located in said base for causing air to move through said air flow channel; and

a controller for detecting an air flow parameter in said work station and connected to said pressure inducing assembly for automatically controlling said pressure inducing assembly based on said detected air flow parameter, said controller comprising;

an air flow detector located in said air flow channel;

a microprocessor connected to said air flow detector for receiving a signal therefrom and for converting said received signal to a digital pulse signal; and

a motor control circuit connected to said microprocessor for receiving said digital pulse signal therefrom, said motor control circuit being connected to said pressure inducing assembly for providing a signal thereto to control the movement of air through said air flow channel.

2. The work station of claim 1, wherein said support comprises first and second supports located on first opposite sides of said work station and wherein said work surface is accessible from opposite sides of said work station different than said first opposite sides of said work station.

3. The work station of claim 2, wherein said pressure inducing assembly comprises:

a first air chamber defined in said base and having a first blower having an first impeller and a first motor; and

a second air chamber defined in said base and having a second blower having a second impeller and a second motor.

4. The work station of claim 3, wherein said air flow detector comprises an air flow sensor circuit including a thermistor located in said air flow channel for detecting a temperature therein, and wherein said motor control circuit is connected to said first and second motor for providing a signal thereto to control a rotational speed thereof.

5. The work station of claim 3, wherein said air flow detector comprises a pressure circuit including a pitot tube located in said air flow channel for detecting a pressure therein, and wherein said motor control circuit being connected to said first and second motor for providing a signal thereto to control a rotational speed thereof.

6. The work station of claim 1, wherein said support comprises a support located at a rear of said work station and wherein said work surface is accessible from a front of said work station.

7. The work station of claim 6, wherein said pressure inducing assembly comprises an air chamber defined in said base and having a blower having a fan and an ECM motor.

8. The work station of claim 7, wherein said controller comprises:

said motor control circuit connected to said motor for receiving a signal therefrom indicating a rotational speed thereof, said motor control circuit being connected to said microprocessor for providing a signal thereto indicating the rotational speed of said motor, said microprocessor providing a signal to said motor control circuit in response to said signal received from said motor control circuit, said motor control circuit being connected to said motor for providing a signal thereto to control a rotational speed thereof based upon said signal received by said motor control circuit from said motor.

9. The work station of claim 1, wherein said perforations are formed about the periphery of said work surface.

10. The work station of claim 1, further comprising a HEPA filter disposed in said air flow channel.

11. The work station of claim 1, further comprising a HEPA filter disposed in said top cabinet.

12. The work station of claim 6, further comprising a HEPA filter disposed in said support.