Air-conditioning apparatus

An air-conditioning system for a plurality of rooms, comprising in combination:

• utility means for supplying a volume of air at a selected temperature,
• first conduit means for transporting air from said utility means to the vicinity of each room,
• means at said utility means for causing air to flow from said utility means through said conduit means, and
• a plurality of distribution means, at least one distribution means connected to said conduit means in the vicinity of each of said rooms, each of said distribution means comprising a housing defining a chamber, first inlet means for transporting air from said first conduit means into said chamber, second inlet means for transporting air from one of said rooms into said chamber, a barometric damper interposed between the second inlet means and the chamber for admitting air from the rooms into the chamber when the pressure in the chamber is less than the pressure of air in the second inlet means, outlet means for transporting air from said chamber into said one of said rooms, a blower which can accept air from said second inlet means and discharge it through the outlet means, temperature altering means for changing the temperature of air flowing through said outlet means, control means operable in response to the temperature in said one of said rooms, said control means being operable in a first range wherein the air transported through said outlet consists of air from said first inlet means, in a second range wherein the air transported through said outlet means consisting of air from said first and second inlet means, in a third range wherein the air transported through said outlet means consists of air from said second inlet, and in a fourth range wherein the air transported through said outlet means consists of air from said second inlet which has been changed in temperature by said temperature altering means.

An air distribution unit adapted to be used in an air-conditioning apparatus which includes a central source of air and is utilized to condition air in a space, which distribution unit comprises:

• a housing defining a volume, said volume having first inlet means for receiving air from the central source, second inlet means for receiving air from a space to be conditioned and an outlet in fluid communication with said housing for discharging conditioned air into the space,
• a blower means for accepting air from said first and second inlet means and discharging it into the outlet in the housing,
• first valve means selectively regulating the flow of air into said volume through said first inlet means,
• second valve means selectively regulating the flow of air into said volume through said second inlet means, the second valve means being responsive to the difference in static pressure between the air inside said volume and the air in the space to be conditioned for admitting air to said volume from said space to be conditioned when the pressure of the air in said volume is less than the pressure of the air in the space to be conditioned.

An air-conditioning system for a plurality of rooms, comprising in combination:

• utility means for supplying a volume of air at a selected temperature,
• first conduit means for transporting air from said utility means to the vicinity of each room,
• pump means at said utility means for causing air to flow from said utility means through said conduit means, and
• a plurality of distribution means, at least one distribution means connected to said conduit means in the vicinity of each of said rooms, each of said distribution means comprising a housing defining a chamber, first inlet means for transporting air from said first conduit means to said chamber, second inlet means for transporting air from one of said rooms to said chamber, outlet means for transporting air from said chamber to said one of said rooms, a blower for accepting air from said first and second inlet means and discharging it through said outlet means, first valve means selectively regulating the flow of air into said chamber through said first inlet means, second valve means selectively regulating the flow of air into said chamber through said second inlet means, control means connected to said second valve means for controlling said second valve means in response to the difference in static pressure between said chamber and said one of said rooms to admit air to said chamber from one of said rooms when the pressure of the air in the chamber is less than the pressure of the air in the space to be conditioned.