Refrigeration – Gas compression – heat regeneration and expansion – e.g.,...
Patent
1997-10-21
1999-09-28
Capossela, Ronald
Refrigeration
Gas compression, heat regeneration and expansion, e.g.,...
277465, 277553, 277560, F25B 900
Patent
active
059569565
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a cryo-refrigerator in which a spacing between an outer circumferential surface of a displacer and an inner circumferential surface of a cylinder is sealed by a seal ring.
BACKGROUND ART
Conventionally, there has been provided a cryo-refrigerator employing a magnetic regenerative material as shown in FIG. 7.
This cryo-refrigerator comprises a first displacer 3 which has a first chamber with an unshown regenerative material accommodated therein and which is reciprocatably fitted in a first cylinder 1, and a second displacer 7 which has a second chamber communicating with the first chamber and accommodating an unshown regenerative material and which is reciprocatably fitted in a second cylinder 5. Then, the first chamber of the first displacer 3 is switchedly communicated with a high-pressure chamber 12 having an inlet 11 or with a low-pressure chamber 14 having an outlet 13, via a valve stem 9 and a valve 10.
The communicating path from the first chamber to either the high-pressure chamber 12 or the low-pressure chamber 14 is switched over by rotating the valve 10 with a synchronous motor 15.
The cryo-refrigerator having the above constitution operates as follows.
Referring to FIG. 7, a high-pressure refrigerant gas fed from a compressor (not shown) or the like is introduced into the first chamber of the first displacer 3 from the inlet 11 via the valve 10 and the valve stem 9, where the refrigerant gas undergoes heat exchange with the regenerative material within the first chamber, thus being cooled (first stage). The refrigerant gas cooled in this way is further introduced into the second chamber within the second displacer 7, where the refrigerant gas undergoes heat exchange with the regenerative material within the second chamber, thus being further cooled (second stage).
After these processes, the valve 10 is rotated by the synchronous motor 15, so that the first chamber is communicated with the low-pressure chamber 14. Then, the high-pressure refrigerant gas that has been introduced in the first chamber and the second chamber is expanded at a breath, lowering in gas temperature. In this way, the low temperature obtained by the expansion of the refrigerant gas is kept by the regenerative material.
As described above, a cryogenic temperature is obtained by iterating the introduction of the high-pressure refrigerant gas into the first chamber and the second chamber as well as its expansion (i.e., by iterating the refrigerating cycle).
Between the second displacer 7 side and the valve stem 9 side in the first cylinder 1, there occurs a pressure difference during the refrigerating cycle. Likewise, a pressure difference occurs between the terminal end side and the first displacer 3 side in the second cylinder 5 while the refrigerating cycle is performed. Therefore, a circular seal ring 21 is attached at a step portion 20 provided in an upper outer circumferential surface of the first displacer 3, thereby sealing between the inner circumferential surface of the first cylinder 1 and the outer circumferential surface of the first displacer 3. Likewise, a circular seal ring 23 is attached at a step portion 22 provided in an upper outer circumferential surface of the second displacer 7, thereby sealing between the inner circumferential surface of the second cylinder 5 and the outer circumferential surface of the second displacer 7.
FIG. 8 is a detailed sectional view of the seal ring 21. The seal ring 21 comprises a seal member 26 formed into a U shape in cross section and having an annular groove 25 opened upward, and an annular coil spring 27 fitted into the annular groove 25 of the seal member 26. Then, an outer circumferential wall 26a of the seal member 26 is biased outward by the coil spring 27, so that the sealing portion of the outer circumferential wall 26a is put into close contact with an inner circumferential surface 1a of the first cylinder 1, by which the spacing between the first cylinder 1 and the first displacer 3 is sealed.
In this arrangemen
REFERENCES:
patent: 1963849 (1934-06-01), Johnson
patent: 3127185 (1964-03-01), Evans
patent: 3364675 (1968-01-01), Dorer
patent: 3396976 (1968-08-01), Reinhoudt et al.
patent: 3847389 (1974-11-01), Rogers
patent: 3861691 (1975-01-01), Wheeler
patent: 4143883 (1979-03-01), Paynter
patent: 4355519 (1982-10-01), Kercheval et al.
patent: 4501120 (1985-02-01), Holland
patent: 4830344 (1989-05-01), Balsells
patent: 5265890 (1993-11-01), Balsells
Morishita Hiroyuki
Torii Hirotoshi
Capossela Ronald
Daikin Industries Ltd.
LandOfFree
Cryogenic refrigerator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cryogenic refrigerator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cryogenic refrigerator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-691510