Incremental electrically actuated valve

Claim 2

A variable flow rate valve comprised of: a valve body defining an internal metering chamber, said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall including a substantially planar outlet surface with an outlet aperture for permitting fluid flow from said metering chamber; a drive shaft disposed in said metering chamber; means for rotationally supporting said drive shaft in substantial axial rigidity; means for incrementally rotating said drive shaft; a substantially rectilinear metering piston disposed in said metering chamber in sliding engagement with said planar outlet surface, said metering piston having a metering orifice; and means for converting rotation of said drive shaft to linear movement of said metering piston, said converting means engaging said drive shaft and further engaging said metering piston.

Claim 3

The variable flow rate valve as set forth in claim 1 wherein said drive shaft is threaded.

Claim 4

The variable flow rate valve as set forth in claim 2 wherein said means for converting rotation of said drive shaft is further comprised of a threaded drive key operably disposed on said drive shaft.

Claim 5

The variable flow rate valve as set forth in claim 3 wherein said metering piston further includes means for engaging said drive key.

Claim 6

The variable flow rate valve as set forth in claim 4 wherein said drive key is substantially rectilinear.

Claim 7

The variable flow rate valve as set forth in claim 5 wherein said metering piston further includes a slot for accepting said drive key.

Claim 8

The variable flow rate valve as set forth in claim 6 wherein said means for rotationally supporting said drive shaft is further comprised of an upper main bearing and a lower main bearing in said internal metering chamber of said valve body.

Claim 9

The variable flow rate valve as set forth in claim 7 wherein said means for incrementally rotating said drive shaft is further comprised of a rotary stepping motor.

Claim 10

A variable flow rate valve comprised of: a valve body defining an internal metering chamber having a substantially planar outlet metering surface. said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall with an outlet aperture for permitting fluid flow from said metering chamber, said valve body further defining a circular upper bore and a base; a substantially rectilinear metering piston disposed in said metering chamber for upward movement and for downward movement, said metering piston including a metering surface in sliding engagement with said planar outlet surface and a horizontal slot in an opposed surface, said metering piston having a metering orifice; a drive key disposed in said horizontal slot for driving engagement with said metering piston, said drive key including a vertical bore therethrough; a drive shaft rotatably disposed in said bore of said drive key; means for rotationally mounting said drive shaft in said valve body, said mounting means providing substantial axial rigidity during the rotation of said drive shaft; and means for incrementally rotating said drive shaft.

Claim 11

A variable flow rate valve comprised of: a valve body defining an internal metering chamber having a substantially planar outlet metering surface. said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall with an outlet aperture for permitting fluid flow from said metering chamber, said valve body further defining a circular upper bore and a base; a substantially rectilinear metering piston disposed in said metering chamber for upward movement and for downward movement, said metering piston including a metering surface in sliding engagement with said planar outlet surface and a horizontal slot in an opposed surface, said metering piston having a metering orifice; a drive key disposed in said horizontal slot for driving engagement with said metering piston, said drive key including a vertical bore therethrough; a drive shaft rotatably disposed in said bore of said drive key; means for rotationally mounting said drive shaft in said valve body, said mounting means providing substantial axial rigidity during the rotation of said drive shaft; and means for incrementally rotating said drive shaft.

Claim 12

The variable flow rate valve as set forth in claim 9 wherein said means for rotationally mounting said drive shaft further includes an upper carrier element fixed to said drive shaft for concurrent rotation; a lower carrier element fixed to said drive shaft for concurrent rotation; means for rotationally supporting said upper carrier element; and means for rotationally supporting said lower carrier element.

Claim 13

The variable flow rate valve as set forth in claim 10 wherein said means for incrementally rotating said drive shaft further includes a stepper motor having an exterior shell and a motor drive shaft, said motor drive shaft fixed to said upper carrier element.

Claim 14

The variable flow rate valve as set forth in claim 11 wherein said valve further includes an anti-rotation pin engaging said motor shell for preventing rotation of said motor shell.

Claim 15

The variable flow rate valve as set forth in claim 12 wherein said upper carrier element further includes an upper carrier stop surface for contacting said drive key to limit upward movement thereof and said lower carrier element further includes a lower carrier stop surface for contacting said drive key to limit downward movement thereof.

Claim 16

A refrigeration system for controllably circulating refrigerant in closed loop connection comprised of: an evaporator for gasifying refrigerant; a compressor in flow connection with said evaporator for receiving and compressing said gasified refrigerant; a condenser in flow connection with said compressor for receiving and liquifying said refrigerant; a variable flow rate expansion valve in flow connection with said condenser for receiving said liquified refrigerant and controllably expanding said refrigerant, said valve being in flow connection for directing said expanded refrigerant to said evaporator, said valve comprised of: a valve body defining an internal metering chamber, said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall including a substantially planar outlet surface with an outlet aperture for permitting fluid flow from said metering chamber; a drive shaft disposed in said metering chamber; means for rotationally supporting said drive shaft in substantial axial rigidity; means for incrementally rotating said drive shaft; a substantially rectilinear metering piston disposed in said metering chamber in sliding engagement with said planar outlet surface, said metering piston having a metering orifice; and means for converting rotation of said drive shaft to linear movement of said metering piston, said converting means engaging said drive shaft and further engaging said metering piston; means for sensing refrigerant condition in said refrigeration system; and means for controllably incrementing said variable flow rate expansion valve in response to said means for sensing refrigerant condition.

Claim 17

A refrigeration system for controllably circulating refrigerant in closed loop connection comprised of: an evaporator for gasifying refrigerant; a compressor in flow connection with said evaporator for receiving and compressing said gasified refrigerant; a condenser in flow connection with said compressor for receiving and liquifying said refrigerant; a variable flow rate expansion valve in flow connection with said condenser for receiving said liquified refrigerant and controllably expanding said refrigerant, said valve being in flow connection for directing said expanded refrigerant to said evaporator, said valve comprised of: a valve body defining an internal metering chamber, said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall including a substantially planar outlet surface with an outlet aperture for permitting fluid flow from said metering chamber; a drive shaft disposed in said metering chamber; means for rotationally supporting said drive shaft in substantial axial rigidity; means for incrementally rotating said drive shaft; a substantially rectilinear metering piston disposed in said metering chamber in sliding engagement with said planar outlet surface, said metering piston having a metering orifice; and means for converting rotation of said drive shaft to linear movement of said metering piston, said converting means engaging said drive shaft and further engaging said metering piston; means for sensing refrigerant condition in said refrigeration system; and means for controllably incrementing said variable flow rate expansion valve in response to said means for sensing refrigerant condition.

Claim 18

The refrigeration system as set forth in claim 14 wherein said drive shaft is threaded.

Claim 19

The refrigeration system as set forth in claim 15 wherein said means for converting rotation of said drive shaft is further comprised of a threaded drive key operably disposed on said drive shaft.

Claim 20

The refrigeration system as set forth in claim 16 wherein said metering piston further includes means for engaging said drive key.

Claim 21

The refrigeration system as set forth in claim 17 wherein said drive key is substantially rectilinear.

Claim 22

The refrigeration system as set forth in claim 18 wherein said metering piston further includes a slot for accepting said drive key.

Claim 23

The refrigeration system as set forth in claim 19 wherein said means for rotationally supporting said drive shaft is further comprised of an upper main bearing and a lower main bearing in said internal metering chamber of said valve body.

Claim 24

The refrigeration system as set forth in claim 20 wherein said means for incrementally rotating said drive shaft is further comprised of a rotary stepping motor.

Claim 25

A refrigeration system for controllably circulating refrigerant in closed loop connection comprised of: an evaporator for gasifying refrigerant; a compressor in flow connection with said evaporator for receiving and compressing said gasified refrigerant; a condenser in flow connection with said compressor for receiving and liquifying said refrigerant; a variable flow rate expansion valve in flow connection with said condenser for receiving said liquified refrigerant and controllably expanding said refrigerant, said valve being in flow connection for directing said expanded refrigerant to said evaporator, said valve comprised of a valve body defining an internal metering chamber having a substantially planar outlet metering surface, said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall with an outlet aperture for permitting fluid flow from said metering chamber, said valve body further defining a circular upper bore and a base; a substantially rectilinear metering piston disposed in said metering chamber for upward movement and for downward movement, said metering piston including a metering surface in sliding engagement with said planar outlet surface and a horizontal slot in an opposed surface, said metering piston having a metering orifice; a drive key disposed in said horizontal slot for driving engagement with said metering piston, said drive key including a vertical bore therethrough; a drive shaft rotatably disposed in said bore of said drive key; means for rotationally mounting said drive shaft in said valve body, said mounting means providing substantial axial rigidity during the rotation of said drive shaft; means for incrementally rotating said drive shaft; means for sensing refrigerant condition in said refrigeration system; and means for controllably incrementing said variable flow rate expansion valve in response to said means for sensing refrigerant condition.

Claim 26

A refrigeration system for controllably circulating refrigerant in closed loop connection comprised of: an evaporator for gasifying refrigerant; a compressor in flow connection with said evaporator for receiving and compressing said gasified refrigerant; a condenser in flow connection with said compressor for receiving and liquifying said refrigerant; a variable flow rate expansion valve in flow connection with said condenser for receiving said liquified refrigerant and controllably expanding said refrigerant, said valve being in flow connection for directing said expanded refrigerant to said evaporator, said valve comprised of a valve body defining an internal metering chamber having a substantially planar outlet metering surface, said valve body having a first wall with an inlet aperture for permitting fluid flow into said metering chamber and a second wall with an outlet aperture for permitting fluid flow from said metering chamber, said valve body further defining a circular upper bore and a base; a substantially rectilinear metering piston disposed in said metering chamber for upward movement and for downward movement, said metering piston including a metering surface in sliding engagement with said planar outlet surface and a horizontal slot in an opposed surface, said metering piston having a metering orifice; a drive key disposed in said horizontal slot for driving engagement with said metering piston, said drive key including a vertical bore therethrough; a drive shaft rotatably disposed in said bore of said drive key; means for rotationally mounting said drive shaft in said valve body, said mounting means providing substantial axial rigidity during the rotation of said drive shaft; means for incrementally rotating said drive shaft; means for sensing refrigerant condition in said refrigeration system; and means for controllably incrementing said variable flow rate expansion valve in response to said means for sensing refrigerant condition.

Claim 27

The refrigeration system as set forth in claim 22 wherein said means for rotationally mounting said drive shaft of said valve further includes an upper carrier element fixed to said drive shaft for concurrent rotation; a lower carrier element fixed to said drive shaft for concurrent rotation; means for rotationally supporting said upper carrier element; and means for rotationally supporting said lower carrier element.

Claim 28

The refrigeration system as set forth in claim 23 wherein said means for incrementally rotating said drive shaft of said valve further includes a stepper motor having an exterior shell and a motor drive shaft, said motor drive shaft fixed to said upper carrier element.

Claim 29

The refrigeration system as set forth in claim 24 wherein said valve further includes an anti-rotation pin engaging said motor shell for preventing rotation of said motor shell.

Claim 30

The refrigeration system as set forth in claim 25 wherein said upper carrier element of said valve further includes an upper carrier stop surface for contacting said drive key to limit upward movement thereof and said lower carrier element further includes a lower carrier stop surface for contacting said drive key to limit downward movement thereof.