US3876385A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe system for operating an autoclave door
Assignee: Johns Manville Corp
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Filing: 1972-07-31
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Granted: 1975-04-08
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Expires: 1992-07-31
Abstract
Abstract A fail-safe key interlock system prevents an autoclave door from being opened when steam pressure within the autoclave is above a predetermined level, and prevents a steam supply valve of the autoclave from being opened unless the autoclave door is closed, latched and locked. The system is fail-safe in that if there is a loss of electrical power or control air pressure, the door cannot be opened and the steam supply valve is closed or remains closed.
Inventors
- 👤 Arthur Russell Markus
- 👤 John Ostapovich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:52
CPC Classifications
B; B01; B01J; B01J3/00; B01J3/03; F; F16; F16J; F16J13/00; F16J13/24
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
188 words
A SYSTEM FOR SAFELY OPERATING A DOOR OF AN AUTOCLAVE WHICH IS NORMALLY PRESSURIZED WHEN IN OPERATION COMPRISING: A. MEANS FOR SENSING PRESSURE WITHIN THE AUTOCLAVE AND FOR PREVENTING THE DOOR FROM BEING OPENED WHEN THE PRESSURE WITHIN THE AUTOCLAVE IS ABOVE A PREDETERMINED LEVEL, THE MEANS FOR SENSING PRESSURE WITHIN THE AUTOCLAVE AND FOR PREVENTING THE DOOR FROM BEING OPENED INCLUDING A FIRST KEY INTERLOCK UNIT, SAID FIRST UNIT HAVING A FIRST LOCK AND KEY FOR SAID LOCK, AND SAID FIRST UNIT HAVING A MEANS FOR PREVENTING REMOVAL OF THE KEY FROM SAID LOCK UNTIL THE PRESSURE WITHIN THE AUTOCLAVE IS BELOW THE PREDETERMINED LEVEL, B. LOCKING MEANS FOR LOCKING THE DOOR IN A CLOSED POSITION, SAID LOCKING MEANS INCLUDING A SECOND KEY INTERLOCK UNIT, SAID SECOND UNIT HAVING A SECOND LOCK WHICH IS FIT BY SAID KEY SO THAT THE DOOR CAN BE UNLOCKED ONLY AFTER SAID KEY HAS BEEN REMOVED FROM SAID FIRST UNIT, AND C. MEANS FOR CLOSING A STEAM SUPPLY VALVE OF THE AUTOCLAVE AND FOR MAINTAINING THE STEAM SUPPLY VALVE CLOSED WHEN THE DOOR IS BEING OPENED, OPEN OR IS BEING CLOSED.
Claim 2
Independent Claim
188 words
A SYSTEM FOR SAFELY OPERATING A DOOR OF AN AUTOCLAVE WHICH IS NORMALLY PRESSURIZED WHEN IN OPERATION COMPRISING: A. MEANS FOR SENSING PRESSURE WITHIN THE AUTOCLAVE AND FOR PREVENTING THE DOOR FROM BEING OPENED WHEN THE PRESSURE WITHIN THE AUTOCLAVE IS ABOVE A PREDETERMINED LEVEL, THE MEANS FOR SENSING PRESSURE WITHIN THE AUTOCLAVE AND FOR PREVENTING THE DOOR FROM BEING OPENED INCLUDING A FIRST KEY INTERLOCK UNIT, SAID FIRST UNIT HAVING A FIRST LOCK AND KEY FOR SAID LOCK, AND SAID FIRST UNIT HAVING A MEANS FOR PREVENTING REMOVAL OF THE KEY FROM SAID LOCK UNTIL THE PRESSURE WITHIN THE AUTOCLAVE IS BELOW THE PREDETERMINED LEVEL, B. LOCKING MEANS FOR LOCKING THE DOOR IN A CLOSED POSITION, SAID LOCKING MEANS INCLUDING A SECOND KEY INTERLOCK UNIT, SAID SECOND UNIT HAVING A SECOND LOCK WHICH IS FIT BY SAID KEY SO THAT THE DOOR CAN BE UNLOCKED ONLY AFTER SAID KEY HAS BEEN REMOVED FROM SAID FIRST UNIT, AND C. MEANS FOR CLOSING A STEAM SUPPLY VALVE OF THE AUTOCLAVE AND FOR MAINTAINING THE STEAM SUPPLY VALVE CLOSED WHEN THE DOOR IS BEING OPENED, OPEN OR IS BEING CLOSED.
Claim 3
Dependent Claim
57 words
The system of claim 1 wherein: a. the means for maintaining the steam supply valve closed includes means for preventing the steam supply valve from being opened in said first key interlock unit which is actuated by moving the key in the first lock to a position where the key can be removed from the first lock.
Claim 4
Dependent Claim
35 words
The system of claim 2 wherein: a. the means for maintaining the steam supply valve closed includes means for preventing the steam supply valve from being opened which is actuated when the door is unlocked.
Claim 5
Dependent Claim
35 words
The system of claim 1 wherein: a. the means for maintaining the steam supply valve closed includes means for preventing the steam supply valve from being opened which is actuated when the door is unlocked.
Claim 6
Dependent Claim
33 words
The system of claim 1 wherein: a. vent means is provided for venting the autoclave; and b. the locking means includes means for opening the vent means as the door is being unlocked.
Claim 7
Independent Claim
278 words
A system for safely operating a door of an autoclave oven which is pressurized when in operation comprising: a. a door having lugs spaced about the perimeter of the door; b. a retaining ring on the autoclave, the retaining ring having lugs spaced about the ring for cooperating with the door lugs to retain the door in a closed position; c. rotating means for rotating the door and the ring relative to each other to latch or unlatch the door by engaging or disengaging the lugs; d. means for opening and closing the door; e. a steam supply valve for supplying the autoclaves with pressurized steam; f. means for sensing pressure within the autoclave and for preventing the door from being opened when the pressure within the autoclave is above a predetermined level, the means for sensing pressure within the autoclave and for preventing the door from being opened including a first key interlock unit, said first unit having a first lock and a key for said lock, and said first unit having a means for preventing removal of the key from said lock until the pressure within the autoclave is below the predetermined level; g. locking means for locking the door in a closed position, said locking means including a second key interlock unit, said second unit having a second lock which is fit by said key so that the door can be unlocked only after said key has been removed from said first unit; and h. means for closing a steam supply valve of the autoclave and for maintaining the steam supply valve closed when the door is being opened, is open or is being closed.
Claim 8
Independent Claim
278 words
A system for safely operating a door of an autoclave oven which is pressurized when in operation comprising: a. a door having lugs spaced about the perimeter of the door; b. a retaining ring on the autoclave, the retaining ring having lugs spaced about the ring for cooperating with the door lugs to retain the door in a closed position; c. rotating means for rotating the door and the ring relative to each other to latch or unlatch the door by engaging or disengaging the lugs; d. means for opening and closing the door; e. a steam supply valve for supplying the autoclaves with pressurized steam; f. means for sensing pressure within the autoclave and for preventing the door from being opened when the pressure within the autoclave is above a predetermined level, the means for sensing pressure within the autoclave and for preventing the door from being opened including a first key interlock unit, said first unit having a first lock and a key for said lock, and said first unit having a means for preventing removal of the key from said lock until the pressure within the autoclave is below the predetermined level; g. locking means for locking the door in a closed position, said locking means including a second key interlock unit, said second unit having a second lock which is fit by said key so that the door can be unlocked only after said key has been removed from said first unit; and h. means for closing a steam supply valve of the autoclave and for maintaining the steam supply valve closed when the door is being opened, is open or is being closed.
Claim 9
Dependent Claim
33 words
The system of claim 6 wherein: a. vent means is provided for venting the autoclave; and b. the locking means includes means for opening the vent means as the door is being unlocked.
Claim 10
Dependent Claim
24 words
The system of claim 7 wherein: a. the locking means includes means for preventing actuation of the rotating means when the door is locked.
Claim 11
Dependent Claim
27 words
The system of claim 8 wherein: a. means is provided to prevent actuation of the means for opening and closing the door unless the door is unlatched.
Claim 12
Dependent Claim
38 words
The system of claim 9 wherein: a. the retaining ring is stationary; b. the door is rotatably mounted on the autoclave; and c. the rotating means rotates the door to effect the latching or unlatching of the door.
Claim 13
Dependent Claim
34 words
The system of claim 9 wherein: a. the retaining ring is rotatably mounted on the autoclave; and b. the rotating means rotates the retaining ring to effect the latching or unlatching of the door.
Claim 14
Dependent Claim
66 words
The system of claim 9 wherein: the means for sensing pressure within the autoclave and for preventing the door from being opened and the means for closing the steam supply valve and for maintaining the steam supply valve closed are electrically and pneumatically operated in such a manner that an electrical or pneumatic failure prevents the door from being opened and closes the steam supply valve.
References Cited (Backward Citations)
US3681008A
Cited
US3780904A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |