Air conditioning unit and control

Claim 2

A control for an air conditioning unit operable to supply air conditioned to a relatively low temperature level at a contral station to an area, said central station being connected to said air conditioning unit through a supply duct, said unit including means to regulate the quantity of air discharged from said unit, said control comprising: a. a pressure responsive valve connected to said air regulating means; b. means connecting said pressure responsive valve to said supply duct, a portion of said conditioned air passing through said pressure responsive valve to provide a control signal to said air regulating means, the magnitUde of said control signal varying directly with changes in pressure of said conditioned air in said supply duct; c. thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means, the magnitude of said signal increasing as the temperature of said area approaches a predetermined value to decrease the quantity of conditioned air supplied from said unit to said area; and d. said connecting means including a port having a temperature responsive element provided thereover to normally close said port, means connecting said port to said thermostat means, said temperature responsive element opening said port when the temperature of said conditioned air supplied from said central station exceeds a predetermined value, said relatively warm air passing through said port to said thermostatic means, said thermostatic means thereby decreasing the magnitude of the control signal from said pressure responsive valve to said air regulating means to a value as determined solely by the pressure of said conditioned air in said supply duct.

Claim 3

A control for an air conditioning unit operable to supply air conditioned to a relatively low temperature level at a central station into an area, said central station being connected to said air conditioning unit through a supply duct, said unit including means to regulate the quantity of air discharged from said unit, said control comprising: a. a pressure responsive valve connected to said air regulating means; b. means connecting said pressure responsive valve to said supply duct to pass a portion of said conditioned air to said pressure responsive valve to provide a control signal to said air regulating means, the magnitude of said control signal varying with changes in pressure of said conditioned air in said supply duct to maintain the quantity of air discharged substantially constant; c. thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means to reduce the quantity of air discharged from the unit as the temperature in said area approaches a predetermined value; and d. said means connecting said pressure responsive valve to said supply duct including a member having a normally open port, conditioned air passing therethrough to said pressure responsive valve, and a normally closed port connected to said thermostatic means, said normally closed port being open when the temperature of said air supplied from said central station exceeds a predetermined value to pass said relatively warm air to said thermostatic means, said thermostatic means thereby becoming ineffective to vary the magnitude of the control signal from said pressure responsive valve to said air regulating means, the magnitude of said signal being determined solely by the pressure of said conditioned air in said supply duct.

Claim 4

A control for an air conditioning unit operable to supply air conditioned to a relatively low temperature level at a central station into an area, said central station being connected to said air conditioning unit through a supply duct, said unit including means to regulate the quantity of air discharged from said unit, said control comprising: a. a pressure responsive valve connected to said air regulating means; b. means connecting said pressure responsive valve to said supply duct to pass a portion of said conditioned air to said pressure responsive valve to provide a control signal to said air regulating means, the magnitude of said control signal varying with changes in pressure of said conditioned air in said supply duct to maintain the quantity of air discharged substantially constant; c. thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means to reduce the quantity of air discharged from the unit as the temperature in said area approaches a predetermined value; and d. said means connecting said pressure responsive valve to said supply duct including a member having a normally open port, conditioned air passing therethrough to said pressure responsive valve, and a normally closed port connected to said thermostatic means, said normally closed port being open when the temperature of said air supplied from said central station exceeds a predetermined value to pass said relatively warm air to said thermostatic means, said thermostatic means thereby becoming ineffective to vary the magnitude of the control signal from said pressure responsive valve to said air regulating means, the magnitude of said signal being determined solely by the pressure of said conditioned air in said supply duct.

Claim 5

A control in accordance with claim 2 wherein said means connecting said pressure responsive valve to said supply duct includes a filter member.

Claim 6

A control in accordance with claim 3 wherein said ports are provided in said filter member.

Claim 7

A control in accordance with claim 4 wherein said normally closed port has a bimetallic member movably disposed thereover, said bimetallic member opening said port when supply air temperature exceeds a predetermined value.

Claim 8

A control in accordance with claim 2 wherein said normally closed port has a bimetallic member movably disposed thereover, said bimetallic member opening said port when said supply air temperature exceeds a predetermined value.

Claim 9

An air conditioning unit for supplying conditioned air into a space to be conditioned, the air being cooled to a relatively low temperature level at a central station, said central station being connected to said air conditioning unit through a supply duct, said unit comprising: a. means to regulate the quantity of air discharged from said unit; b. a pressure responsive valve connected to said air regulating means and said supply duct to provide a control signal to said air regulating means, the magnitude of said control signal varying with changes in pressure of said conditioned air in said supply duct; c. thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means, the magnitude of said control signal approaching a value so the air regulating means decreases the quantity of conditioned air supplied from said unit into said area as the temperature of said area approaches a predetermined value; and d. means connected to said thermostatic means and said pressure responsive means, said means including a normally open port through which conditioned air passes from said supply duct to said pressure responsive valve and a normally closed port communicating with said thermostatic means, said normally closed port opening when the temperature of said conditioned air supplied from said central station through said supply duct exceeds a predetermined value, said relatively warm air passing through said port to said thermostatic means, said thermostatic means thereby becoming ineffective to vary the magnitude of the control signal from said pressure responsive valve to said air regulating means, the magnitude of said signal being determined solely by the pressure of said conditioned air in said supply duct.

Claim 10

An air conditioning unit for supplying conditioned air into a space to be conditioned, the air being cooled to a relatively low temperature level at a central station, said central station being connected to said air conditioning unit through a supply duct, said unit comprising: a. means to regulate the quantity of air discharged from said unit; b. a pressure responsive valve connected to said air regulating means and said supply duct to provide a control signal to said air regulating means, the magnitude of said control signal varying with changes in pressure of said conditioned air in said supply duct; c. thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means, the magnitude of said control signal approaching a value so the air regulating means decreases the quantity of conditioned air supplied from said unit into said area as the temperature of said area approaches a predetermined value; and d. means connected to said thermostatic means and said pressure responsive means, said means including a normally open port through which conditioned air passes from said supply duct to said pressure responsive valve and a normally closed port communicating with said thermostatic means, said normally closed port opening when the temperature of said conditioned air supplied from said central station through said supply duct exceeds a predetermined value, said relatively warm air passing through said port to said thermostatic means, said thermostatic means thereby becoming ineffective to vary the magnitude of the control signal from said pressure responsive valve to said air regulating means, the magnitude of said signal being determined solely by the pressure of said conditioned air in said supply duct.

Claim 11

An air conditioning unit in accordance with claim 7 wherein said means having a normally closed port includes filter means.

Claim 12

An air conditioned unit in accordance with claim 8 wherein said normally closed port has a bimetallic element disposed thereover, said bimetallic element moving to open the port when the temperature of the air in the supply duct exceeds a predetermined value.

Claim 13

An air conditioning unit in accordance with claim 7 wherein said normally closed port has a bimetallic element disposed thereover, said bimetallic elements moving to open the port when the temperature of the air in the supply duct exceeds a predetermined value.