US5122344A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemical sterilizer system
Assignee: MDT Corp
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Filing: 1990-01-31
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Granted: 1992-06-16
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Expires: 2010-01-31
Abstract
Abstract A chemical sterilizer system for sterilizing items by vaporizing a liquid chemical sterilant in a sterilizing chamber. Pre-evacuation of the sterilizer chamber enhances the sterilizing activity. Sterilant is injected into the sterilizer chamber from a prefilled shot chamber. Subsequent to the exposure period, spent sterilant is condensed and fresh air is pumped into the sterilizer chamber from a vacuum pump. An automated valving system uses a minimal number of three-way valves and one or more two-way valves to control the fluid flow functions in the sterilization cycle.
Inventors
- 👤 John C. Schmoegner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:44
CPC Classifications
A; A61; A61L; A61L2/00; A61L2/16; A61L2/18; A61L2/02; A61L2/04; A61L2/06; A61L2/20; A61L2/24
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
197 words
A method of sterilizing materials with a liquid chemical sterilant vaporized in a sealable, heated sterilizer chamber, comprising: placing materials to be sterilized in said sterilizer chamber and sealing said sterilizer chamber; heating said sterilizer chamber to a sterilant evaporation temperature; pre-evacuating a portion of the atmosphere from said sterilizer chamber with a vacuum pump and producing a reduced pressure in said sterilizer chamber; disengaging said vacuum pump from said sterilizer chamber at a predetermined reduced pressure therein; introducing a predetermined quantity of said liquid chemical sterilant by gravity from a pre-filled shot chamber into said sterilizer chamber for vaporization therein and for mixture with residual atmosphere therein; heating said sterilizer chamber and contents to a controlled sterilization temperature for vaporizing said introduced chemical sterilant; maintaining said sterilization temperature for a timed period; discharging spent vaporized sterilant and air from said sterilizer chamber through cooling means to condense and cool said vaporized sterilant; engaging said vacuum pump to pump atmospheric air into said sterilizer chamber to rapidly cool said chamber and dilute said vaporized sterilant; and passing said discharged, cooled and condensed spent sterilant to a condensate reservoir for separating said condensed sterilant from gases and vapors.
Claim 2
Independent Claim
197 words
A method of sterilizing materials with a liquid chemical sterilant vaporized in a sealable, heated sterilizer chamber, comprising: placing materials to be sterilized in said sterilizer chamber and sealing said sterilizer chamber; heating said sterilizer chamber to a sterilant evaporation temperature; pre-evacuating a portion of the atmosphere from said sterilizer chamber with a vacuum pump and producing a reduced pressure in said sterilizer chamber; disengaging said vacuum pump from said sterilizer chamber at a predetermined reduced pressure therein; introducing a predetermined quantity of said liquid chemical sterilant by gravity from a pre-filled shot chamber into said sterilizer chamber for vaporization therein and for mixture with residual atmosphere therein; heating said sterilizer chamber and contents to a controlled sterilization temperature for vaporizing said introduced chemical sterilant; maintaining said sterilization temperature for a timed period; discharging spent vaporized sterilant and air from said sterilizer chamber through cooling means to condense and cool said vaporized sterilant; engaging said vacuum pump to pump atmospheric air into said sterilizer chamber to rapidly cool said chamber and dilute said vaporized sterilant; and passing said discharged, cooled and condensed spent sterilant to a condensate reservoir for separating said condensed sterilant from gases and vapors.
Claim 3
Dependent Claim
38 words
The method of claim 1, further comprising: the step following the introduction of said sterilant into said sterilizer chamber of disengaging said shot chamber from said sterilizer chamber and prefilling said shot chamber for a subsequent sterilization cycle.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein said gases and vapors are withdrawn from said condensate reservoir and are passed through a filter.
Claim 5
Dependent Claim
417 words
The method of claim 1 wherein said sterilizer chamber is provided with a solenoid valve control system, sterilant inlet conduit means, exhaust conduit means, a liquid sterilant reservoir means with a vapor space, sterilant injection means including said shot chamber for supplying sterilant to said sterilizer chamber means, evacuation means with a suction port and a discharge port, spent sterilant condensing means, waste reservoir means with a vapor space and a drain, and electronic control means, said solenoid valve control system comprising: first three-way valve means with a first port connected by a first conduit to said sterilizer chamber, a second port connected by a second conduit to the bottom of said shot chamber, and a third port connected by a third conduit to said sterilant reservoir means; second three-way solenoid valve means with a first port connected by a first conduit to said sterilizer chamber, a second port connected by a second conduit to the top of said shot chamber, and a third port connected by a third conduit to said vapor space of said sterilant means; third three-way solenoid valve means with a first port connected by a first conduit to said sterilizer chamber means, a second port connected by a second conduit to said suction port of said evacuation means, and a third port connected by a third conduit to the atmosphere; fourth three-way solenoid valve means with a first port connected by a first conduit to said vapor space of said waste reservoir means, a second port connected by a second conduit to said discharge port of said evacuation means, and a third port connected by a third conduit to said sterilant chamber; first two-way solenoid valve means with a first port connected by a first conduit to said sterilizer chamber means and a second port connected by a second conduit to said spent sterilant condensing means; and condensate conduit means connecting said condensing means to said waste reservoir means; wherein said first and second three-way valves are operable between a first position for filling said shot chamber with said liquid sterilant and a second position for injecting said liquid sterilant into said sterilizer chamber; and wherein said third and fourth three-way valves are operable between a first position for evacuating said sterilizer chamber, a second position for blocking flow to or from said sterilizer chamber, and a third position for purging said sterilizer chamber with air pumped by said evacuation means; said solenoid valve control system being operated to effect said method.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-16 | 1995-12-16 | 1996-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-16 | 1999-12-16 | 2000-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-16 | 2003-12-16 | 2004-06-16 | $7700.00 | Window Closed / Lapsed |