Temperature control system

Claim 2

A temperature control system for controlling the temperature of a room or the like having access to outside air, comprising, in combination, first control means controlling an air conditioning medium, damper means to selectively control the flow of air from within the room and from outside the room to subject said air to said air conditioning medium, thermostat means having an inlet and an outlet, a two-level source of fluid pressure, first conduit means including second control means interconnecting said pressure source to said inlet of said thermostat means, said second control means being operable to selectively connect said thermostat means to either of said two levels of pressure, switch means responsive to the pressure at the inlet of said thermostat means, means connecting said outlet of said thermostat means To said first control means and to said damper means to operate the same, said thermostat means being responsive to a first pressure from said source to control said first control means to temper air maintaining the room at a first temperature, said thermostat means being responsive to a second pressure from said source to control first control means to maintain the temperature within the room at a second temperature, said switch means being responsive to both said first and second pressure to maintain said damper means in condition to circulate only inside air to said room, and means provided for causing a momentary predetermined decrease in pressure in said inlet, said switch means being responsive to said momentary decrease for placing said damper means under control of said thermostat such that a mixture of airflow from within and outside the room is conditioned by said air conditioning medium while said thermostat means controls the temperature within the room at said second temperature.

Claim 3

A control system as defined in claim 1 wherein said means for causing a momentary predetermined decrease in pressure comprises means for momentarily connecting said inlet to atmospheric pressure.

Claim 4

A control system as defined in claim 1 wherein said second control means includes said means for causing a said predetermined decrease in pressure.

Claim 5

A temperature control system for controlling the temperature of a room or the like having access to outside air, comprising, in combination, first control means controlling the flow of an air conditioning medium, damper means to selectively control the flow of air from within the room and from outside the room to subject said air to said air conditioning medium, thermostat means having an inlet and an outlet, a two-level source of fluid pressure, first conduit means including second control means interconnecting said pressure source to said inlet of said thermostat means, said second control means being operable to selectively connect said thermostat means to either of said two levels of pressure, switch means having a first section responsive to the pressure at the outlet of said thermostat means, said switch means having second and third sections responsive to the pressure at the inlet of said thermostat means, means connecting said outlet of said thermostat means to said first control means and to said damper means to operate the same, said thermostat means being responsive to a first pressure from said source to control said first control means to temper air maintaining the room at a first temperature, said thermostat means being responsive to a second pressure from said source to control said first control means to maintain the temperature within the room at a second temperature, said switch means being responsive to both said first and second pressures to maintain said damper means in condition to circulate only inside air to said room, and means provided for causing a momentary predetermined decrease in pressure in said inlet, said switch means being responsive to said momentary decrease for placing said damper means under control of said thermostat such that a mixture of airflow from within and outside the room is conditioned by said air conditioning medium while said thermostat means controls the temperature within the room at said second temperature.

Claim 6

A temperature control system for controlling the temperature of a room or the like having access to outside air, comprising, in combination, first control means controlling the flow of an air conditioning medium, damper means to selectively control the flow of air from within the room and from outside the room to subject said air to said air conditioning medium, thermostat means having an inlet and an outlet, a two-level source of fluid pressure, first conduit means including second control means interconnecting said pressure source to said inlet of said thermostat means, said second control means being operable to selectively connect said thermostat means to either of said two levels of pressure, switch means having a first section responsive to the pressure at the outlet of said thermostat means, said switch means having second and third sections responsive to the pressure at the inlet of said thermostat means, means connecting said outlet of said thermostat means to said first control means and to said damper means to operate the same, said thermostat means being responsive to a first pressure from said source to control said first control means to temper air maintaining the room at a first temperature, said thermostat means being responsive to a second pressure from said source to control said first control means to maintain the temperature within the room at a second temperature, said switch means being responsive to both said first and second pressures to maintain said damper means in condition to circulate only inside air to said room, and means provided for causing a momentary predetermined decrease in pressure in said inlet, said switch means being responsive to said momentary decrease for placing said damper means under control of said thermostat such that a mixture of airflow from within and outside the room is conditioned by said air conditioning medium while said thermostat means controls the temperature within the room at said second temperature.

Claim 7

A control system as defined in claim 4, wherein said means for causing a momentary predetermined decrease in pressure comprises means for momentarily connecting said inlet to atmospheric pressure.

Claim 8

A control system as defined in claim 4 wherein said second control means includes said means for causing a said predetermined decrease in pressure.

Claim 9

A control system as defined in claim 4 wherein said switch means comprises pressure electric relay means having said first, second and third sections, said first section being connected through pressure conduit means to said outlet of said thermostat means, and said second and third sections being connected to said first conduIt means so as to be responsive to the pressure within said first conduit means as determined by said second control means.

Claim 10

A control system as defined in claim 4 including fan means operatively connected to said switch means for selectively effecting flow of air from said damper means into the room.

Claim 11

A control system as defined in claim 8 including means connecting said fan means to said first and second sections of said switch means such that said fan means is controlled for intermittent operation by said thermostat means when said thermostat is subjected to said first pressure from said source, said fan means being continuously energized when said thermostat means and said switch means are subjected to said second pressure from said source.