Integration of automated cryopump safety purge
First Claim
1. A method of controlling a cryopump, the method comprising:
- monitoring a temperature sensor coupled to the cryopump to determine whether the temperature sensor is functioning;
determining a potentially unsafe condition in response to an inability to determine a reading from the temperature sensor coupled to the cryopump;
automatically responding to the inability to determine the temperature reading by initiating an automated safety purge routine that releases a normally open purge valve coupled to the cryopump to deliver purge gas to dilute potentially hazardous gas; and
preventing the safety purge routine from being aborted by maintaining the normally open purge valve open until the potentially unsafe condition changes to a safe condition.
7 Assignments
0 Petitions
Accused Products
Abstract
A system and method is provided to control a purge valve during an unsafe condition associated with a cryopump. An electronic controller may be used to control the opening and closing of one or more purge valves during the unsafe condition. The purge valve can be a cryo-purge valve or exhaust purge valve. The purge valve can be a normally open valve. The electronic controller can release the normally open valve in response to the unsafe condition. The electronic controller can delay its response to the unsafe condition for a safe period of time. Attempts from other systems to control these valves during unsafe conditions can be preempted during unsafe conditions. A user can be inhibited from manually controlling the purge valve during unsafe conditions. A power failure recovery routine may be initiated in response to a restoration of power. The power failure recovery routine can respond to an unsafe condition even if the power failure recovery routine has been manually turned off by a user.
49 Citations
18 Claims
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1. A method of controlling a cryopump, the method comprising:
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monitoring a temperature sensor coupled to the cryopump to determine whether the temperature sensor is functioning; determining a potentially unsafe condition in response to an inability to determine a reading from the temperature sensor coupled to the cryopump; automatically responding to the inability to determine the temperature reading by initiating an automated safety purge routine that releases a normally open purge valve coupled to the cryopump to deliver purge gas to dilute potentially hazardous gas; and preventing the safety purge routine from being aborted by maintaining the normally open purge valve open until the potentially unsafe condition changes to a safe condition. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 14, 16)
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9. A system for controlling a cryopump comprising:
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an electronic controller configured to monitor a temperature sensor coupled to the cryopump to determine whether the temperature sensor is functioning; the electronic controller configured to determine a potentially unsafe condition in response to an inability to determine a temperature from the temperature sensor coupled to the cryopump; the electronic controller configured to automatically respond to the inability to determine a temperature from the temperature sensor by causing a normally open purge valve coupled to the cryopump to deliver purge gas to dilute potentially hazardous gas; and the electronic controller preventing the safety purge routine from being aborted by maintaining the normally open purge valve open until the potentially unsafe condition changes to a safe condition. - View Dependent Claims (10, 11, 12, 15, 17)
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13. A cryopump comprising:
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an electronic controller configured to monitor a temperature sensor coupled to the cryopump; the electronic controller configured to determine a potentially unsafe condition in response to an inability to determine a temperature reading from the temperature sensor coupled to the cryopump; the electronic controller configured to automatically respond to the potentially unsafe condition by initiating an automated cryopump safety purge routine that causes a normally open purge valve coupled to the cryopump to deliver gas to dilute potentially hazardous gas; and the electronic controller configured to prevent the safety purge routine from being aborted by maintaining the normally open purge valve open until the potentially unsafe condition changes to a safe condition. - View Dependent Claims (18)
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Specification