Autoclave vent

• US 4,781,898 A
• Filed: 05/01/1987
• Issued: 11/01/1988
• Est. Priority Date: 05/01/1987
• Status: Expired due to Fees

• Current Assignee: Siemens Medical Systems, Inc. (Siemens AG)
• Original Assignee: Pelton & Crane LLC
• Inventors: Jones, Arthur L.
• Primary Examiner(s): Richman, Barry S.
• Assistant Examiner(s): WARDEN, JILL ALICE
• Application Number:
  US07/045,969
• Time in Patent Office: 550 Days
• Field of Search: 422/116, 422/26, 422/27, 422/105, 422/112, 422/108, 422/292, 422/295, 422/305
• US Class Current: 422/295
• CPC Class Codes: A61L 2/06 Hot gas
• CPC Class Codes: A61L 2/24 Apparatus using programmed or automatic operation

Abstract

The sterilizing pressure chamber of an autoclave is provided with two valve controlled vent paths. At the end of the sterilizing cycle of the autoclave a first vent path channels the sterilizing steam from the chamber into a condensing coil having an end which opens into a liquid reservoir. When the pressure within the chamber drops to a predetermined level, a second vent path, having a flow rate which is greater than the first path, opens and provides a channel for the rapid escape of the remainder of the steam from the chamber.

Claims

1. An autoclave, comprising:

a supply tank for holding therein a supply of a liquid;

a pressure chamber;

dosing means coupled between said supply tank and said chamber for allowing the entry into said chamber of a predetermined amount of the liquid at the beginning of a sterilization cycle of said autoclave;

a heater coupled to said pressure chamber for generating within said chamber a vapor phase of at least a portion of the predetermined amount of liquid which is allowed to enter said chamber during said sterilization cycle;

a first vent path means for venting the vapor phase of the liquid from said chamber into said supply tank at a first flow rate when open;

a second vent path means for venting the vapor phase of the liquid from said chamber into said supply tank at a second flow rate which is greater than said first rate, when open;

a microprocessor controller for controlling a plurality of time/temperature/pressure cycles for sterilizing items placed in said chamber;

a pressure sensor arrangement for developing a signal representative of the pressure of the vapor phase of the liquid within said chamber; and

wherein said microprocessor controller controls the opening of said first and second vent paths, said microprocessor controller being responsive to said pressure representative signal for controlling the opening of said second vent path at the end of said sterilize cycle.

2. The autoclave of claim 1, wherein:

at the end of said sterilize cycle of said autoclave, said microprocessor controller first causes said first vent path to open, and when said pressure representative signal reaches a pressure level inside said chamber, causes said second vent path to open.

3. The autoclave of claim 1, wherein:

said first vent path comprises a first vapor exhaust line having one end open to said chamber and another end coupled to an input of a first flow control valve and a condensing coil having one end open to said supply tank and another end coupled to an outlet of said first flow control valve.

4. The autoclave of claim 3 wherein:

6. The autoclave of claim 4, wherein:

said microprocessor controller is responsive to said pressure representative signal for controlling the opening of said second flow control valve.

8. The autoclave of claim 6, wherein:

10. The autoclave of claim 6, wherein:

said microprocessor controller causes said heater to heat said chamber after the end of said sterilize chamber, thereby causing a dry cycle of said autoclave; and

said microprocessor controller causes said second flow control valve to be open during said dry cycle.

11. The autoclave of claim 6, wherein:

5. said second vent path comprises a second vapor exhaust line having one end open to said chamber, another end open to said supply tank and a second flow control valve coupled between said ends of said second vapor exhaust line.

7. The autoclave of claim 5, wherein:

at the end of said sterilize cycle of said autoclave, said microprocessor controller first causes said first flow control valve to open, and when said pressure representative signal reaches a predetermined level representative of a predetermined lower pressure level inside said chamber, causes said second flow control valve to open.

9. said microprocessor controller causes said second flow control valve to be open while said dosing means allows the entry into said chamber of the predetermined amount of the liquid at the beginning of said sterilize cycle.

12. said microprocessor controller causes said second valve to only be closed during said sterilize cycle.