Suction throttling valve for automotive refrigerant system

Claim 2

A suction throttling valve for regulating the pressure conditions within an evaporator unit of an automobile air conditioning system wherein the evaporator unit is connected in refrigerant flow relationship with a condenser, expansion means and an engine driven compressor comprising: a housing having an inlet and an outlet, a movable carriage in said housing having a first valve member thereon movable therewith, a second valve member movable relative to the first member and including an opening therethrough defining a first valve seat for said first valve member, means within said housing forming a less restricted opening normally closed by said second valve member, control means responsive to a first pressure condition within said evaporator to move said carriage and said first valve member out of seated engagement with the opening through said second valve member whereby flow from the inlet to the outlet of the housing is directed through said second valve member opening to produce a first restricted flow of fluid from the evaporator to the compressor for reducing the pressure therein to compensate for a first evaporator heat load, said first valve member being opened and closed against said second valve member opening to maintain the evaporator pressure above a predetermined pressure to prevent water from freezing on the outside of the evaporator, said control means responding to a second pressure condition within the evaporator produced by a greater heat load thereon and operating to move said carriage and said first valve to a second control position wherein said first valve member lifts said second valve member from a seated relationship with respect to said second less restricted opening to cause the compressor to draw more refrigerant from the evaporator to reduce the pressure therein to the desired pressure level under the greater evaporator heat load conditions.

Claim 3

A suction throttling valve for controlling pressure within the evaporator of an automotive air conditioning system comprising: a housing having an inlet adapted to be connected to the evaporator and an outlet adapted to be connected to the inlet of an engine-driven compressor; means forming a poppet valve seat at the housing outlet, means forming a pressure chamber at the housing inlet, a pilot bleed hole communicating the housing inlet and the pressure chamber, a movable member located within said housing between said inlet and outlet, said movable member having one end located within said pressure chamber and an opposite end located in overlying relationship to said valve seat, a first poppet valve element secured to said movable member for movement therewith, a second poppet valve element supported for movement on said first poppet valve element including a portion thereon engageable with said first valve seat for closing said first valve seat, said second poppet valve element having means thereon forming a second valve seat, said first poppet valve element being engageable with said second valve seat for controlling flow thereacross, means for producing a pressure differential on said movable member for moving said member into a position to cause said first poppet valve element to close against said second valve seat to close it and to move said second valve element to close said first valve seat to prevent flow of refrigerant from said housing inlet through the outlet thereof, pressure responsive means including a pilot valve responsive to a first pressure increase at the inlet of said housing to reduce the pressure within said pressure chamber to cause said movable member to shift saiD first poppet valve element from said second valve seat to allow a limited flow of refrigerant from said housing inlet to said housing outlet, said pressure responsive means responding to a further pressure increase at the inlet of said housing to further shift said movable member in a direction to move said second poppet valve element away from said first seat to allow greater flow of refrigerant from said housing inlet through said housing outlet, said pressure responsive means responding to a predetermined reduction of pressure in the evaporator to produce a pressure differential across said movable member to cause it to close said first and second poppet valve elements to prevent a pressure reduction in the evaporator which will cool it below a temperature at which water will freeze on the outside surface of the evaporator.

Claim 4

A suction throttling valve for controlling pressure within the evaporator of an automotive air conditioning system comprising: a housing having an inlet adapted to be connected to the evaporator and an outlet adapted to be connected to the inlet of an engine-driven compressor; means forming a poppet valve seat at the housing outlet, means forming a pressure chamber at the housing inlet, a pilot bleed hole communicating the housing inlet and the pressure chamber, a movable member located within said housing between said inlet and outlet, said movable member having one end located within said pressure chamber and an opposite end located in overlying relationship to said valve seat, a first poppet valve element secured to said movable member for movement therewith, a second poppet valve element supported for movement on said first poppet valve element including a portion thereon engageable with said first valve seat for closing said first valve seat, said second poppet valve element having means thereon forming a second valve seat, said first poppet valve element being engageable with said second valve seat for controlling flow thereacross, means for producing a pressure differential on said movable member for moving said member into a position to cause said first poppet valve element to close against said second valve seat to close it and to move said second valve element to close said first valve seat to prevent flow of refrigerant from said housing inlet through the outlet thereof, pressure responsive means including a pilot valve responsive to a first pressure increase at the inlet of said housing to reduce the pressure within said pressure chamber to cause said movable member to shift saiD first poppet valve element from said second valve seat to allow a limited flow of refrigerant from said housing inlet to said housing outlet, said pressure responsive means responding to a further pressure increase at the inlet of said housing to further shift said movable member in a direction to move said second poppet valve element away from said first seat to allow greater flow of refrigerant from said housing inlet through said housing outlet, said pressure responsive means responding to a predetermined reduction of pressure in the evaporator to produce a pressure differential across said movable member to cause it to close said first and second poppet valve elements to prevent a pressure reduction in the evaporator which will cool it below a temperature at which water will freeze on the outside surface of the evaporator.

Claim 5

A two stage suction throttling valve for maintaining a minimum control pressure within the evaporator of an automotive air conditioning system of the type including a compressor discharging refrigerant into a condenser which is connected in refrigerant flow relationship through an expansion device to the inlet of the evaporator, comprising: a housing having its inlet adapted to be connected to the evaporator outlet and an outlet adapted to be connected to the suction line of the compressor, a movable carriage having a first poppet valve thereon, means forming a first unrestricted opening between the inlet and the outlet of said housing, an axially movable second poppet valve closing said first opening, said second poppet valve having a more restricted opening therein located coaxially of said first opening, said first poppet valve located interiorly of said second poppet valve including a flange member thereon movable relative with respect to said second poppet valve member, said carriage locating said first poppet member in a closed position with respect to the opening through said second poppet member and into an opened position with respect thereto, said first poppet member having a third control position, coacting means on said first poppet valve and said second poppet valve engageable when said first poppet valve is in its third control position to lift said second poppet valve from said unrestricted opening, control means for positioning said carriage in response to pressure conditions within said evaporator including means for producing a pressure differential on said carriage, said carriage responding to a first pressure differential to move said second poppet valve to communicate the housing inlet with said housing outlet through said restricted opening to produce a first pressure reduction in said evaporator to reduce the pressure therein in response to a first evaporator heat load, said control means responding to a greater pressure in said evaporator to produce a second pressure differential on said valve carriage to move it and said second poppet valve to its third control position and lift said first poppet valve from said less restricted opening to produce a less restricted fluid flow path between the inlet and outlet of said housing to produce a second reduction in pressure within the evaporator for compensating for an increased heat load on the evaporator, said control means regulating the carriage position to cause said poppet valves to close to prevent the pressure in the evaporator from being reduced below a pressure at which water will freeze on the outer surface of the evaporator.

Claim 6

A two stage suction throttling valve for maintaining a minimum control pressure within the evaporator of an automotive air conditioning system of the type including a compressor discharging refrigerant into a condenser which is connected in refrigerant flow relationship through an expansion device to the inlet of the evaporator, comprising: a housing having its inlet adapted to be connected to the evaporator outlet and an outlet adapted to be connected to the suction line of the compressor, a movable carriage having a first poppet valve thereon, means forming a first unrestricted opening between the inlet and the outlet of said housing, an axially movable second poppet valve closing said first opening, said second poppet valve having a more restricted opening therein located coaxially of said first opening, said first poppet valve located interiorly of said second poppet valve including a flange member thereon movable relative with respect to said second poppet valve member, said carriage locating said first poppet member in a closed position with respect to the opening through said second poppet member and into an opened position with respect thereto, said first poppet member having a third control position, coacting means on said first poppet valve and said second poppet valve engageable when said first poppet valve is in its third control position to lift said second poppet valve from said unrestricted opening, control means for positioning said carriage in response to pressure conditions within said evaporator including means for producing a pressure differential on said carriage, said carriage responding to a first pressure differential to move said second poppet valve to communicate the housing inlet with said housing outlet through said restricted opening to produce a first pressure reduction in said evaporator to reduce the pressure therein in response to a first evaporator heat load, said control means responding to a greater pressure in said evaporator to produce a second pressure differential on said valve carriage to move it and said second poppet valve to its third control position and lift said first poppet valve from said less restricted opening to produce a less restricted fluid flow path between the inlet and outlet of said housing to produce a second reduction in pressure within the evaporator for compensating for an increased heat load on the evaporator, said control means regulating the carriage position to cause said poppet valves to close to prevent the pressure in the evaporator from being reduced below a pressure at which water will freeze on the outer surface of the evaporator.

Claim 7

A two stage suction throttling valve for maintaining a minimum control pressure within the evaporator of an automotive air conditioning system of the type including a compressor discharging refrigerant into a condenser which is connected in refrigerant flow relationship through an expansion device to the inlet of the evaporator, comprising: a housing having its inlet adapted to be connected to the evaporator outlet and an outlet adapted to be connected to the suction line of the compressor, a movable carriage having a first poppet valve theReon, means forming a first unrestricted opening between the inlet and the outlet of said housing, an axially movable second poppet valve closing said first opening, said second poppet valve having a more restricted opening therein located coaxially of said first opening, said first poppet valve located interiorly of said second poppet valve including a flange member thereon movable relative with respect to said second poppet valve member, said carriage locating said first poppet member in a closed position with respect to the opening through said second poppet member and into an opened position with respect thereto, said first poppet member having a third control position, coacting means on said first poppet valve and said second poppet valve engageable when said first poppet valve is in its third control position to lift said second poppet valve from said unrestricted opening, control means for positioning said carriage in response to pressure conditions within said evaporator including a pilot valve responsive to a first pressure condition in the evaporator to bypass refrigerant from the evaporator to the outlet of said housing when both said first and second poppet valves are in a closed position, means for producing a pressure differential on said carriage when said pilot valve bypasses said closed first and second poppet valves, said carriage responding to a first pressure differential to move said second poppet valve to communicate the housing inlet with said housing outlet through said restricted opening to produce a first pressure reduction in said evaporator to reduce the pressure therein in response to a first evaporator heat load, said control means responding to a greater pressure in said evaporator to position said pilot valve to produce a second pressure differential on said valve carriage to move it and said second poppet valve to its third control position and lift said first poppet valve from said less restricted opening to produce a less restricted fluid flow path between the inlet and outlet of said housing to produce a second reduction in pressure within the evaporator for compensating for an increased heat load on the evaporator, said control means and said pilot valve regulating the pressure bypass control action thereof to cause said poppet valves to close to prevent the pressure in the evaporator from being reduced below a pressure at which water will freeze on the outer surface of the evaporator.

Claim 8

A two stage suction throttling valve for maintaining a minimum control pressure within the evaporator of an automotive air conditioning system of the type including a compressor discharging refrigerant into a condenser which is connected in refrigerant flow relationship through an expansion device to the inlet of the evaporator, comprising: a housing having its inlet adapted to be connected to the evaporator outlet and an outlet adapted to be connected to the suction line of the compressor, a movable carriage having a first poppet valve theReon, means forming a first unrestricted opening between the inlet and the outlet of said housing, an axially movable second poppet valve closing said first opening, said second poppet valve having a more restricted opening therein located coaxially of said first opening, said first poppet valve located interiorly of said second poppet valve including a flange member thereon movable relative with respect to said second poppet valve member, said carriage locating said first poppet member in a closed position with respect to the opening through said second poppet member and into an opened position with respect thereto, said first poppet member having a third control position, coacting means on said first poppet valve and said second poppet valve engageable when said first poppet valve is in its third control position to lift said second poppet valve from said unrestricted opening, control means for positioning said carriage in response to pressure conditions within said evaporator including a pilot valve responsive to a first pressure condition in the evaporator to bypass refrigerant from the evaporator to the outlet of said housing when both said first and second poppet valves are in a closed position, means for producing a pressure differential on said carriage when said pilot valve bypasses said closed first and second poppet valves, said carriage responding to a first pressure differential to move said second poppet valve to communicate the housing inlet with said housing outlet through said restricted opening to produce a first pressure reduction in said evaporator to reduce the pressure therein in response to a first evaporator heat load, said control means responding to a greater pressure in said evaporator to position said pilot valve to produce a second pressure differential on said valve carriage to move it and said second poppet valve to its third control position and lift said first poppet valve from said less restricted opening to produce a less restricted fluid flow path between the inlet and outlet of said housing to produce a second reduction in pressure within the evaporator for compensating for an increased heat load on the evaporator, said control means and said pilot valve regulating the pressure bypass control action thereof to cause said poppet valves to close to prevent the pressure in the evaporator from being reduced below a pressure at which water will freeze on the outer surface of the evaporator.