Automatic temperature and humidity regulation – Thermostatic – In fluid controlled
Patent
1998-02-05
2000-06-27
Tapolcai, William E.
Automatic temperature and humidity regulation
Thermostatic
In fluid controlled
251 9, G05D 2308
Patent
active
060796286
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to valves for use in heated and pressurized fluid flow, such as the conveyancing of steam. In particular, the present invention relates to a self-contained, thermostatic temperature and pressure operated pinch valve in which the path of fluid flow through said valve may be automatically controlled by the temperature and pressure of a flow material, said pinch valve comprising: path of said flow material; defining at least a portion of said flow transport path, said flow adjustment means adapted to alternatively decrease the fluid flow in that portion of said flow transport path defined by said flow adjustment means upon an increase of pressure on a surface of the flow adjustment means or increase the fluid flow in the path upon a decrease of pressure on a surface of the flow adjustment means; and, pressure and temperature communication with said flow material, said flow measurement chamber being further provided with sensing means in direct pressure and temperature communication with the flow material; and, said flow adjustment means, said closure chamber being further provided with a closure means in direct operative communication with said flow adjustment means, and in operative communication with said sensing means;
wherein, said closure means is adapted to provide operative pressure upon said flow adjustment means in response to changes in the temperature and pressure of the flow material as determined by said sensing means.
2. Description of Related Art
Various forms of valves and steam traps are known which employ a plug-within-a-seat to interrupt the flow of steam. Where the steam is pressurized, however, the valve actuation means must be sensitive to both temperature and pressure, and not just temperature alone. In order to prevent the passage of live steam through the valve, without backing up a column of condensate, such a valve must follow the steam curve, i.e., the liquid-vapor transition of the fluid as a function of both its temperature and pressure. A number of activation means are known which are said to be sensitive to both temperature and pressure, i.e., they follow the steam curve. These include bimetallic discs, float, open bucket or inverted bucket, and bellows mechanisms.
Plug-within-a-seat valves and steam traps, however, are subject to failure in systems containing any kind of dirt or grit, wherein a small particle of dirt can prevent the plug from seating correctly and cause the valve to malfunction.
An alternative to plug-within-a-seat construction, which does not suffer from this kind of failure, is the pinch valve. In such construction, the steam flows through a conduit, at least a portion of which is elastomeric, and the flow can be interrupted by squeezing the elastomeric walls together (pinch). While this type of construction has been employed in constructions in which a temperature sensitive fluid expands to close off the elastomeric passageway, this known construction is sensitive only to temperature, not the combination of temperature and pressure, and cannot be employed in applications which require the valve to follow the steam curve.
Applicant is not aware of the application of a pinch valve construction in a valve or steam trap design in which the activation mechanism is sensitive to temperature and pressure, such as the activation methodologies enumerated above.
Certainly, one of the most pertinent references to the present invention is U.S. Pat. No. 4,454,983 to Tarvis, entitled TEMPERATURE CONTROLLED VALVE. This reference shows a control valve used as a steam trap with a flexible flow tube surrounded by a chamber filled with a fluid having a high co-efficient of thermal expansion in thermal contact with the flow. Changes in temperature of the flow will cause changes in the fluid volume, constricting the flexible flow tube. While the device of this reference is sensitive to the temperature of the flow, it is relatively isolated from the pressure of the flow, and so does not follow th
REFERENCES:
patent: 566977 (1896-09-01), Frolich
patent: 596581 (1898-01-01), Edson
patent: 875320 (1907-12-01), Burnet
patent: 880030 (1908-02-01), Leavitt
patent: 1048508 (1912-12-01), Dunham
patent: 1120707 (1914-12-01), Froehlich
patent: 1198918 (1916-09-01), Holmberg
patent: 2095506 (1937-10-01), Leutwiler et al.
patent: 2279002 (1942-04-01), MacNeil
patent: 2590215 (1952-03-01), Sausa
patent: 2804773 (1957-09-01), Domingo et al.
patent: 2842331 (1958-07-01), Anderson
patent: 2884866 (1959-05-01), Patterson
patent: 2902222 (1959-09-01), Noakes
patent: 3017903 (1962-01-01), Steffens
patent: 3022670 (1962-02-01), Sutliffe, Jr.
patent: 3145967 (1964-08-01), Gardner
patent: 3353560 (1967-11-01), McCulloch
patent: 3514034 (1970-05-01), Cushman
patent: 3687365 (1972-08-01), Laessig
patent: 3701513 (1972-10-01), Carter
patent: 3901438 (1975-08-01), Christiansson
patent: 3947528 (1976-03-01), Decker
patent: 4039003 (1977-08-01), Cheek
patent: 4049017 (1977-09-01), Jones
patent: 4114640 (1978-09-01), Forman
patent: 4136854 (1979-01-01), Ehmig et al.
patent: 4248376 (1981-02-01), Foller
patent: 4368754 (1983-01-01), Roberts
patent: 4454983 (1984-06-01), Tarvis, Jr.
patent: 4569502 (1986-02-01), Elliott
patent: 4586873 (1986-05-01), Lepretre et al.
patent: 4657043 (1987-04-01), Ampferer et al.
patent: 4679584 (1987-07-01), Wolff
patent: 4727902 (1988-03-01), Unterstein et al.
patent: 4790344 (1988-12-01), Chauvier et al.
patent: 4841739 (1989-06-01), Wallner
patent: 4877053 (1989-10-01), Yusko, Jr. et al.
patent: 4895341 (1990-01-01), Brown et al.
patent: 4899783 (1990-02-01), Yusko, Jr. et al.
patent: 4936339 (1990-06-01), Bennett
patent: 5107883 (1992-04-01), Shaw
patent: 5358202 (1994-10-01), Tse et al.
Photocopy of guide "Steam and Steam Trapping", cover page and pp. 1-20, Spirax Sarco Ltd., 1982.
Photocopy of brochure "Bestobell Steam--Steam Traps and Steam Specialties", by Bestobell Steam (admitted prior art).
LandOfFree
Self-contained temperature and pressure operated pinch valve does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Self-contained temperature and pressure operated pinch valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-contained temperature and pressure operated pinch valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1776787