Claims
- 1. A trap apparatus comprising:an exhaust passage for evacuating a sealed chamber by a vacuum pump; a regenerating passage disposed adjacent to said exhaust passage; a sealed trapping and regenerating casing extending across said exhaust passage and said regenerating passage; a trap unit movably housed in said trapping and regenerating casing for selective movement between a trapping position connected to said exhaust passage and a regenerating position connected to said regenerating passage; a first valve body disposed on one side of said trap unit; a second valve body disposed on a second side of said trap unit; a first seal disposed on an outer circumferential surface of said first valve body; and a second seal disposed on an outer circumferential surface of said second valve body, wherein said first and second seals can be projected so as to be in close contact with the inner circumferential surface of said trapping and regenerating casing, and each of said first and second seals can be retracted so as not to be in contact with the inner circumferential surface of said trapping and regenerating casing.
- 2. A trap apparatus according to claim 1, wherein each of said first and second valve bodies comprises movable plates for projecting said corresponding seal into contact with the inner circumferential surface of said trapping and regenerating casing and for retracting said seal to a position that is not in contact with the inner circumferential surface of said trapping and regenerating casing.
- 3. A trap apparatus according to claim 1, wherein said seal comprises a double seal.
- 4. A trap apparatus according to claim 3, wherein a seal monitoring mechanism is provided for monitoring sealing variations in sealed spaces between each of said double seals.
- 5. A trap apparatus according to claim 4, wherein said seal monitoring mechanism comprises a pressure sensor for detecting pressure variations in said sealed spaces.
- 6. A trap apparatus according to claim 4, wherein said seal monitoring mechanism comprising a mass flow meter for detecting flow rate variations from said sealed spaces.
- 7. A trap apparatus according to claim 4, wherein said seal monitoring mechanism comprises a device for creating a vacuum in said sealed spaces and monitoring a sealing capability of the seals based on a variation of said vacuum.
- 8. A trap apparatus according to claim 4, wherein said seal monitoring mechanism comprises a device for creating a pressurized state in said sealed spaces and monitoring a sealing capability of the seals based on a variation in the pressurized state.
- 9. A trap apparatus according to claim 1, wherein said trap unit has a trapping efficiency that is greater toward the center of the trap unit.
- 10. A trap apparatus according to claim 1, wherein each of said first and second valve bodies comprises a pair of discs that are movable toward and away from each other.
- 11. A trap apparatus according to claim 10, wherein each disc of said pair of discs has a tapered surface on its outer circumferential edge.
- 12. A trap apparatus according to claim 11, wherein the tapered surfaces of said pair of discs of said first valve body oppose each other so as to form a recess in which the first seal is disposed.
Priority Claims (2)
Number |
Date |
Country |
Kind |
2000-345139 |
Nov 2000 |
JP |
|
2001-8325 |
Jan 2001 |
JP |
|
Parent Case Info
This is a divisional application of Ser. No. 09/986,672, filed Nov. 9, 2001 now U.S. Pat. No. 6,553,811.
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Non-Patent Literature Citations (1)
Entry |
US 6,398,831, 6/2002, Nomura (withdrawn) |