Refrigeration system flow control expansion valve

A method for delivering a refrigerant from a high pressure region to a low pressure region of a refrigeration system through a variable dimension passageway to allow the refrigerant to expand as it enters the low pressure region comprising the steps of:

• a) coupling the high and low pressure regions through a valve body having a refrigerant inlet and a refrigerant outlet and a metering head defining first and second passageways for fluid passing through the valve body;
• b) mounting a sleeve having a center passageway for controlled movement within the valve body so that refrigerant passing through the first and second passageways of the metering head also passes through the center passageway of the sleeve before said refrigerant reaches the refrigerant outlet of the valve body;
• c) biasing the sleeve in a direction relative the metering head to maintain both the first and second passageways in fluid communication with the center passageway of the device;
• and
• d) selectively moving the sleeve against the biasing action applied in step (c) to block flow through one passageway of the first and second passageways while allowing continued refrigerant flow through another of the first and second passageways to reach the refrigeration outlet.

A refrigeration expansion valve comprising:

• a) a valve body having a valve inlet for accepting refrigerant and a valve outlet for delivering refrigerant through the valve body, said valve body including a metering head defining first and second passageways for fluid passing through the valve body;
• b) a valving element mounted for controlled movement within the valve body and including a valving element passageway which in combination with the first and second passageways conveys fluid through the valve body to the valve outlet;
• and
• c) a valve actuator mounted to the valve body for moving the valving element to a position blocking flow through one passageway of the first and second passageways while allowing fluid to flow through another of the first and second passageways and said valve element passageway to the outlet, said valve actuator including a control input responsive to an external control signal to control positioning of the valving element.

In a refrigeration system having a compressor, evaporator, and condensor connected in series, an expansion valve connected between the evaporator and the condensor comprising:

• a) a valve body having a valve inlet for accepting refrigerant and a valve outlet for delivering refrigerant through the valve body, said valve body including a metering head defining first and second passageways for refrigerant passing through the valve body, wherein the metering head includes a generally cylindrical cavity forming part of the first passageway and said first passageway passes through a tip of the metering head and opens into said cylindrical cavity;
• b) a valving element mounted for controlled movement within the valve body and including a valving element passageway which in combination with the first and second passageways conveys refrigerant through the valve body to the valve outlet, said valving element comprising a sleeve defining a center passageway co-axially aligned with the cylindrical cavity in the metering head;
• c) a biasing member supported within said cylindrical cavity for biasing the valving element away from the metering head;
• and
• d) a valve actuator mounted to the valve body for moving the valving element to a position for restricting refrigerant flow through one of said first and second passageways while allowing refrigerant flow through the other of said first and second passageways and said valve element passageway to the outlet, said valve actuator including a control input responsive to an external control signal to control positioning of the valving element.

In a refrigeration system having a compressor, evaporator, and condensor connected in series, an expansion valve connected between the evaporator and the condensor comprising:

• a) a valve body having a valve inlet for accepting refrigerant and a valve outlet for delivering refrigerant that has passed through the valve body, said valve body including a metering head that defines first and second passageways for refrigerant passing through the valve body;
• b) a valving element mounted for controlled movement within the valve body and including a valving element passageway which in combination with the first and second passageways conveys refrigerant through the valve body to the valve outlet when the valving element is in a first position;
• and
• c) a valve actuator mounted to the valve body for moving the valving element to a second position for substantially blocking refrigerant flow through one of said first and second passageways while allowing refrigerant flow through the other of said first and second passageways and said valve element passageway to the outlet, said valve actuator including a control input responsive to an external control signal of variable duration to control positioning of the valving element by repeatedly moving the valving element between said first and second positions.

A method for delivering a refrigerant from a high pressure region to a low pressure region of a refrigeration system through a variable dimension passageway to allow the refrigerant to expand as it enters the low pressure region, the method comprising steps .of:

• a) coupling the high and low pressure regions through a valve body having a refrigerant inlet and a refrigerant outlet and a metering head that defines first and second passageways for refrigerant passing through the valve body;
• b) mounting a sleeve having a center passageway for controlled movement within the valve body between a first position in which refrigerant passes through the first and second passageways of the metering head and through the center passageway of the sleeve to reach the refrigerant outlet of the valve body, and a second position in which refrigerant flow is restricted through one of said first and second passageways but permitted through the other of said first and second passageways and through the center passageway of the sleeve to reach the refrigeration outlet of the valve body;
• c) biasing the sleeve in a direction relative the metering head to said first position to maintain both the first and second passageways in fluid communication with the center passageway of the sleeve;
• and
• d) applying an external control signal of variable duration to reciprocate the sleeve against said biasing between said tint and second positions to control the flow of refrigerant to the refrigeration outlet.