Patent US3834175A successfully refreshed from Google Patents.
US3834175A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Servo temperature control valve for refrigeration system
Assignee: Motors Liquidation Co
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Filing: 1973-08-31
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Granted: 1974-09-10
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Expires: 1993-08-31
Abstract
Abstract A vapor compression type air conditioning system including a defrost control servo valve between the compressor and the evaporator and in bypass relationship to a condenser and expansion valve which directs a metered quantity of warm refrigerant directly to the evaporator to maintain an evaporator temperature above 32* F. A thermostatic element responsive to evaporator refrigerant temperature moves a pilot needle valve which controls the pressure in a variable volume control chamber formed on one end of a piston. A main needle valve extending from the other end of the piston is moved with the piston in response to pressure changes in the control chamber to a location corresponding to the position of the pilot needle valve. The main needle valve coacts with a bypass opening to regulate the quantity of warm refrigerant introduced to the evaporator.
Inventors
- 👤 D Jones
- 👤 C Cook
- 👤 A Murray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:46
CPC Classifications
F; F25; F25B; F25B47/00; F25B47/02; F25B47/022; F25B41/00; F25B41/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
400 words
An air conditioning system comprising: an evaporator for cooling air in a passenger compartment; a compressor for pressurizing refrigerant drawn from said evaporator; a condenser for cooling refrigerant discharged from said compressor; expansion valve means for controlling the quantity of refrigerant introduced to said evaporator; a defrost servo control valve fluidly connected between said compressor and said evaporator in bypass relationship to said condenser and said expansion valve means to direct a quantity of warm refrigerant from said compressor into said evaporator for maintaining said evaporator temperature above a freeze level; said defrost servo control valve including a housing with an inlet fluidly connected to the outlet of the compressor and an outlet fluidly connected to the evaporator; a valve member coactive with said inlet to regulate the quantity of warm refrigerant introduced to said evaporator; a piston slidably mounted in a cylinder with said valve member connected to one end to position said valve member with respect to said inlet; the other end of said piston forming with said cylinder a variable volume control chamber which is fluidly connected by a small bleed orifice to said inlet to transmit refrigerant pressure therebetween; a tubular valve seat extending from said other end of said piston through said control chamber and into and adjacent enclosure which is fluIdly connected to said outlet of the evaporator; said tubular valve seat forming a passage for withdrawing refrigerant from said control chamber into said enclosure; a pilot valve in said enclosure coactive with the end of said tubular valve seat for opening and closing said passage to regulate the pressure within said control chamber and thereby causing said piston and connected tubular valve seat to attain a position in said housing with the end of said tubular valve seat contacting said pilot valve member; a thermostatic element in said enclosure with a member movable with temperature changes of evaporator refrigerant; said movable member being operably connected to said pilot valve to position said pilot valve with respect to the end of said tubular valve seat in response to refrigerant temperature changes, whereby the position of said thermostatic element and connected pilot valve control the location of said tubular valve seat and connected piston which moves said main valve member with respect to said inlet to direct sufficient warm refrigerant from the compressor to the evaporator for maintaining said evaporator temperature above a freeze level.
Claim 2
Dependent Claim
400 words
An air conditioning system comprising: an evaporator for cooling air in a passenger compartment; a compressor for pressurizing refrigerant drawn from said evaporator; a condenser for cooling refrigerant discharged from said compressor; expansion valve means for controlling the quantity of refrigerant introduced to said evaporator; a defrost servo control valve fluidly connected between said compressor and said evaporator in bypass relationship to said condenser and said expansion valve means to direct a quantity of warm refrigerant from said compressor into said evaporator for maintaining said evaporator temperature above a freeze level; said defrost servo control valve including a housing with an inlet fluidly connected to the outlet of the compressor and an outlet fluidly connected to the evaporator; a valve member coactive with said inlet to regulate the quantity of warm refrigerant introduced to said evaporator; a piston slidably mounted in a cylinder with said valve member connected to one end to position said valve member with respect to said inlet; the other end of said piston forming with said cylinder a variable volume control chamber which is fluidly connected by a small bleed orifice to said inlet to transmit refrigerant pressure therebetween; a tubular valve seat extending from said other end of said piston through said control chamber and into and adjacent enclosure which is fluIdly connected to said outlet of the evaporator; said tubular valve seat forming a passage for withdrawing refrigerant from said control chamber into said enclosure; a pilot valve in said enclosure coactive with the end of said tubular valve seat for opening and closing said passage to regulate the pressure within said control chamber and thereby causing said piston and connected tubular valve seat to attain a position in said housing with the end of said tubular valve seat contacting said pilot valve member; a thermostatic element in said enclosure with a member movable with temperature changes of evaporator refrigerant; said movable member being operably connected to said pilot valve to position said pilot valve with respect to the end of said tubular valve seat in response to refrigerant temperature changes, whereby the position of said thermostatic element and connected pilot valve control the location of said tubular valve seat and connected piston which moves said main valve member with respect to said inlet to direct sufficient warm refrigerant from the compressor to the evaporator for maintaining said evaporator temperature above a freeze level.
Claim 3
Dependent Claim
392 words
An air conditioning system comprising: an evaporator for cooling air in a passenger compartment; a compressor for pressurizing refrigerant drawn from said evaporator; a condenser for cooling refrigerant discharged from said compressor; expansion valve means for controlling the quantity of refrigerant introduced to said evaporator; a defrost servo control valve fluidly connected between said compressor and said evaporator in bypass relationship to said condenser and said expansion valve means to direct a quantity of warm refrigerant from said compressor into said evaporator for maintaining said evaporator temperature above a freeze level; said defrost servo control valve including a housing with an inlet fluidly connected to the outlet of the compressor and an outlet fluidly connected to the evaporator; a needle valve member extending into said inlet to regulate the quantity of warm refrigerant introduced to said evaporator; a piston slidably mounted in a cylinder with said needle valve member connected to one end to position said member in said inlet; the other end of said piston forming with said cylinder a variable volume control chamber which is fluidly connected by a small bleed orifice to said inlet to transmit refrigerant pressure therebetween; a tubular valve seat extending from said other end of said piston through said control chamber and into an adjacent enclosure which is fluidly connected to said outlet of the evaporator; said tubular valve seat forming a passage for withdrawing refrigerant from said control chamber into said enclosure; a pilot needle valve in said enclosure coactive with the end of said tubular valve seat for opening and closing said passage to regulate the pressure within said control chamber and thereby causing said piston and connected tubular valve seat to attain a position in said housing with the end of said tubular valve seat contacting said pilot valve; a thermostatic element in said enclosure having a member movable with temperature changes of evaporator refrigerant; said movable member being operably connected to said pilot valve to position said pilot valve with respect to the end of said tubular valve seat in response to refrigerant temperature changes, whereby the position of said thermostatic element and connected pilot valve controls the location of said tubular valve seat and connected piston and main needle valve to direct sufficient warm refrigerant from the compressor to the evaporator for maintaining said evaporator temperature above a freeze level.
Claim 4
Dependent Claim
392 words
An air conditioning system comprising: an evaporator for cooling air in a passenger compartment; a compressor for pressurizing refrigerant drawn from said evaporator; a condenser for cooling refrigerant discharged from said compressor; expansion valve means for controlling the quantity of refrigerant introduced to said evaporator; a defrost servo control valve fluidly connected between said compressor and said evaporator in bypass relationship to said condenser and said expansion valve means to direct a quantity of warm refrigerant from said compressor into said evaporator for maintaining said evaporator temperature above a freeze level; said defrost servo control valve including a housing with an inlet fluidly connected to the outlet of the compressor and an outlet fluidly connected to the evaporator; a needle valve member extending into said inlet to regulate the quantity of warm refrigerant introduced to said evaporator; a piston slidably mounted in a cylinder with said needle valve member connected to one end to position said member in said inlet; the other end of said piston forming with said cylinder a variable volume control chamber which is fluidly connected by a small bleed orifice to said inlet to transmit refrigerant pressure therebetween; a tubular valve seat extending from said other end of said piston through said control chamber and into an adjacent enclosure which is fluidly connected to said outlet of the evaporator; said tubular valve seat forming a passage for withdrawing refrigerant from said control chamber into said enclosure; a pilot needle valve in said enclosure coactive with the end of said tubular valve seat for opening and closing said passage to regulate the pressure within said control chamber and thereby causing said piston and connected tubular valve seat to attain a position in said housing with the end of said tubular valve seat contacting said pilot valve; a thermostatic element in said enclosure having a member movable with temperature changes of evaporator refrigerant; said movable member being operably connected to said pilot valve to position said pilot valve with respect to the end of said tubular valve seat in response to refrigerant temperature changes, whereby the position of said thermostatic element and connected pilot valve controls the location of said tubular valve seat and connected piston and main needle valve to direct sufficient warm refrigerant from the compressor to the evaporator for maintaining said evaporator temperature above a freeze level.
Claim 5
Dependent Claim
323 words
A defrost servo control valve adapted to be fluidly connected between a refrigerant compressor and evaporator of an air conditioning system comprising: a valve housing having an inlet and an outlet adapted to be connected to the compressor outlet and evaporator inlet respectively; a needle valve member extending Into said inlet for regulating the flow of warm refrigerant from the compressor to the evaporator; a piston slidably mounted in a cylinder and operably connected at one end to said needle valve member for positioning it in said inlet; the other end of said piston forming a variable volume control chamber with said cylinder and which is fluidly connected by a small bleed orifice to said inlet to transmit refrigerant pressure therebetween; a tubular valve seat portion of said piston extending from said other end of the piston through said control chamber and into an adjacent enclosure which fluidly connects with the evaporator outlet; said tubular valve seat forming passage for withdrawing refrigerant from said control chamber into said enclosure; a pilot needle valve in said enclosure coactive with the end of said tubular valve seat for opening and closing said passage to regulate the pressure within said control chamber and thereby causing said piston and connected tubular valve seat to attain a position in said housing with the end of said tubular valve seat contacting said pilot valve; a thermostatic element in said enclosure with a member movable with temperature changes of evaporator refrigerant; said movable member being operably connected to said pilot valve to position said pilot valve with respect to the end of said tubular valve seat in response to refrigerant temperature changes, whereby the position of said thermostatic element and connected pilot valve controls the location of said piston which moves said main needle valve with respect to said inlet to direct sufficient warm refrigerant from the compressor to the evaporator for maintaining said evaporator temperature above a freeze level.
Claim 6
Dependent Claim
323 words
A defrost servo control valve adapted to be fluidly connected between a refrigerant compressor and evaporator of an air conditioning system comprising: a valve housing having an inlet and an outlet adapted to be connected to the compressor outlet and evaporator inlet respectively; a needle valve member extending Into said inlet for regulating the flow of warm refrigerant from the compressor to the evaporator; a piston slidably mounted in a cylinder and operably connected at one end to said needle valve member for positioning it in said inlet; the other end of said piston forming a variable volume control chamber with said cylinder and which is fluidly connected by a small bleed orifice to said inlet to transmit refrigerant pressure therebetween; a tubular valve seat portion of said piston extending from said other end of the piston through said control chamber and into an adjacent enclosure which fluidly connects with the evaporator outlet; said tubular valve seat forming passage for withdrawing refrigerant from said control chamber into said enclosure; a pilot needle valve in said enclosure coactive with the end of said tubular valve seat for opening and closing said passage to regulate the pressure within said control chamber and thereby causing said piston and connected tubular valve seat to attain a position in said housing with the end of said tubular valve seat contacting said pilot valve; a thermostatic element in said enclosure with a member movable with temperature changes of evaporator refrigerant; said movable member being operably connected to said pilot valve to position said pilot valve with respect to the end of said tubular valve seat in response to refrigerant temperature changes, whereby the position of said thermostatic element and connected pilot valve controls the location of said piston which moves said main needle valve with respect to said inlet to direct sufficient warm refrigerant from the compressor to the evaporator for maintaining said evaporator temperature above a freeze level.
References Cited (Backward Citations)
US3715894A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |