Combination steam and unsaturated chemical vapor sterilizer

• US 4,592,896 A
• Filed: 08/22/1983
• Issued: 06/03/1986
• Est. Priority Date: 05/07/1981
• Status: Expired due to Term

• Current Assignee: Barnstead Thermolyne Corporation (Perspecta, Inc.)
• Original Assignee: MDT Biologic Company
• Inventors: Runnells, Robert R., Larkin, Rodney B., Vandervelden, Keith, Haak, Peter A.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Ledbetter, Jr., Titus B.
• Application Number:
  US06/525,168
• Time in Patent Office: 1,016 Days
• Field of Search: 422/3, 422/11, 422/25, 422/26, 422/33, 422/39, 422/113, 422/292, 422/295, 422/296, 422/95, 422/109, 236/92 C, 220/203
• US Class Current: 422/109
• CPC Class Codes: A61L 2/07 Steam
• CPC Class Codes: A61L 2/20 Gaseous substances, e.g. vapours
• CPC Class Codes: A61L 2/24 Apparatus using programmed or automatic operation

Abstract

A temperature sensor/pressure relief valve has a sensing end positioned within the pressure chamber of a sterilizer and an exhaust end positioned outside the pressure chamber. The temperature sensor is cooperatively adapted to a terminal apparatus at the sensing end to form a pressure relief valve.

Claims

1. A temperature sensor/pressure relief valve having a sensing end and an exhaust end mounted to a pressure chamber of a sterilizer so that the sensing end is inside the chamber and the exhaust end is outside the chamber, comprising:

a hollow, impervious cylindrical housing having a first end comprising said sensing end with a terminal aperture of diameter less than the inside diameter of the housing, and an open second end comprising said exhaust end in communication with an ambient environment exterior to the chamber;

an impervious temperature sensor including means for electronically connecting it to interface circuitry means, said temperature sensor being slidably mounted within the housing near said sensing end so that it is positioned, selectively, to make contact with said terminal aperture, the cross-sectional diameter of the temperature sensor being less than the inside diameter of the housing to allow gases, vapors, fluids and steam to pass therebetween, but greater than the diameter of said terminal aperture, so that a seal is formed when the temperature sensor contacts said terminal aperture; and

means for urging the temperature sensor against the sensing end until the pressure within the pressure chamber exceeds a predetermined pressure, thereby causing the temperature sensor to separate from the terminal aperture, partially releasing sterilizing chemicals, fluids, vapors or steam through said terminal aperture to said ambient environment until the pressure is reduced to or below the predetermined pressure.

2. A temperature sensor/pressure relief valve according to claim 1, including means for thermally isolating the temperature sensor from the housing.

3. A temperature sensor/pressure relief valve according to claim 1, wherein the means for urging the temperature sensor against the sensing end comprises a hollow cylindrical compression spring mounted within the housing, said spring having a preselected spring constant.