Patent US2378091A successfully refreshed from Google Patents.
Patent US3754572A successfully refreshed from Google Patents.
US3754572A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic control system for a fuel burning apparatus or the like
Assignee: Robertshaw Controls Co
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Filing: 1971-11-10
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Granted: 1973-08-28
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Expires: 1991-11-10
Abstract
Abstract This disclosure relates to a pneumatic control system for a clothes dryer wherein the flow of fuel to the main burner means is pneumatically controlled in such a manner that the ignition means for the main burner means must be first pneumatically actuated before the pneumatic control system will pneumatically open the fuel supply means to the main burner means, the control system including a pneumatically operated logic ''''memory'''' unit to assure that the ignition means is always pneumatically operated before the main burner means can be pneumatically operated to its on condition by a pneumatically operated ''''nand'''' unit each time there is a requirement to turn on the main burner means. The ''''memory'''' unit is prevented from transmitting atmosphere therethrough when being switched by its setting signal.
Inventors
- 👤 D Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:09
CPC Classifications
F; F23; F23N; F23N1/00; G; G05; G05B; G05B11/00; G05B11/44; G05B11/58; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/86622; Y10T137/8663
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
245 words
A pneumatically operated control system comprising a pneumatic source, a pneumatically operated unit having a housing means carrying a plurality of spaced diaphragm means that move in unison relative to said housing means and cooperate therewith to define at least first, second and third chambers in stacked relation, said housing means having first and second valve seats leading respectively to said first chamber and to said third chamber and being adapted to be opened and closed by said diaphragm means, first means for interconnecting said source to said second chamber to move said diaphragm means to close said first valve seat and open said second valve seat and for interconnecting the atmosphere to said second chamber to cause said diaphragm means to move to close said second valve seat and open said first valve seat, second means for interconnecting said source to said second valve seat, said diaphragm means having passage means therethrough always interconnecting said first and third chambers together, said first means also interconnecting the atmosphere to said first valve seat at substantially the same time it interconnects the atmosphere to said second chamber and having disconnecting means to disconnect the atmosphere from said first valve seat when said first means is interconnecting said source to said second chamber whereby said first chamber is disconnected from the atmosphere during the time it takes said second chamber to switch said diaphragm means from closing said second valve seat tO opening said second valve seat.
Claim 2
Dependent Claim
245 words
A pneumatically operated control system comprising a pneumatic source, a pneumatically operated unit having a housing means carrying a plurality of spaced diaphragm means that move in unison relative to said housing means and cooperate therewith to define at least first, second and third chambers in stacked relation, said housing means having first and second valve seats leading respectively to said first chamber and to said third chamber and being adapted to be opened and closed by said diaphragm means, first means for interconnecting said source to said second chamber to move said diaphragm means to close said first valve seat and open said second valve seat and for interconnecting the atmosphere to said second chamber to cause said diaphragm means to move to close said second valve seat and open said first valve seat, second means for interconnecting said source to said second valve seat, said diaphragm means having passage means therethrough always interconnecting said first and third chambers together, said first means also interconnecting the atmosphere to said first valve seat at substantially the same time it interconnects the atmosphere to said second chamber and having disconnecting means to disconnect the atmosphere from said first valve seat when said first means is interconnecting said source to said second chamber whereby said first chamber is disconnected from the atmosphere during the time it takes said second chamber to switch said diaphragm means from closing said second valve seat tO opening said second valve seat.
Claim 3
Dependent Claim
46 words
A pneumatically operated control system as set forth in claim 1 wherein spring means is carried by said housing means and is operatively associated with said diaphragm means to tend to normally maintain said diaphragm means in a position thereof that closes said second valve seat.
Claim 4
Dependent Claim
37 words
A pneumatically operated control system as set forth in claim 1 wherein said housing means has a passage interconnecting said third chamber with the exterior of said housing means regardless of the position of said diaphragm means.
Claim 5
Dependent Claim
38 words
A pneumatically operated control system as set forth in claim 1 wherein said first means include a passage defining means between said source and said first and second chambers, said passage defining means having a restriction means therein.
Claim 6
Dependent Claim
30 words
A pneumatically operated control system as set forth in claim 4 wherein said passage defining means has a part thereof bypassing said restriction and leading to said first valve seat.
Claim 7
Dependent Claim
34 words
A pneumatically operated control system as set forth in claim 5 wherein said part of said passage defining means has a one-way check valve therein that defines said disconnecting means of said first means.
Claim 8
Dependent Claim
32 words
A pneumatically operated control system as set forth in claim 4 wherein a one-way check valve means is disposed in said passage defining means between said restriction means and said second chamber.
Claim 9
Dependent Claim
38 words
A pneumatically operated control system as set forth in claim 7 wherein said housing means has a passage interconnecting said third chamber with the exterior of said housing means, said passage defining means being interconnected to said passage.
Claim 10
Dependent Claim
18 words
A pneumatically operated control system as set forth in claim 1 wherein said source is a vacuum source.
Claim 11
Dependent Claim
233 words
A pneumatically operated control system comprising a pneumatic source, a pneumatically operated unit having a housing means carrying a movable means that cooperates therewith to define at least first, second and third chambers in stacked relation, said housing means having first and second valve seats leading respectively to said first chamber and to said third chamber and being adapted to be opened and closed by said movable means, first means for interconnecting said source to said second chamber to move said movable means to close said first valve seat and open said second valve seat and for interconnecting the atmosphere to said second chamber to cause said movable means to move to close said second valve seat and open said first valve seat, second means for interconnecting said source to said second valve seat, said movable means having passage means therethrough always interconnecting said first and third chambers together, said first means also interconnecting the atmosphere to said first valve seat at substantially the same time it interconnects the atmosphere to said second chamber and having disconnecting means to disconnect the atmosphere from said first valve seat when said first means is interconnecting said source to said second chamber whereby said first chamber is disconnected from the atmosphere during the time it takes said second chamber to switch said movable means from closing said second valve seat to opening said second valve seat.
Claim 12
Dependent Claim
233 words
A pneumatically operated control system comprising a pneumatic source, a pneumatically operated unit having a housing means carrying a movable means that cooperates therewith to define at least first, second and third chambers in stacked relation, said housing means having first and second valve seats leading respectively to said first chamber and to said third chamber and being adapted to be opened and closed by said movable means, first means for interconnecting said source to said second chamber to move said movable means to close said first valve seat and open said second valve seat and for interconnecting the atmosphere to said second chamber to cause said movable means to move to close said second valve seat and open said first valve seat, second means for interconnecting said source to said second valve seat, said movable means having passage means therethrough always interconnecting said first and third chambers together, said first means also interconnecting the atmosphere to said first valve seat at substantially the same time it interconnects the atmosphere to said second chamber and having disconnecting means to disconnect the atmosphere from said first valve seat when said first means is interconnecting said source to said second chamber whereby said first chamber is disconnected from the atmosphere during the time it takes said second chamber to switch said movable means from closing said second valve seat to opening said second valve seat.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |