Room air conditioner having compressor with variable capacity and control therefor

Claim 1

A room air conditioner for cooling and dehumidifying a room, comprising: a single cylinder hermetic compressor, including a piston, and a cylinder wall having a number of ports therein spaced axially relative to the cylinder axis, in that part of the length of the cylinder wall traversed by the head end of said piston; valve means for said ports, said valve means having one position corresponding to full capacity operation of said compressor closing all of said ports, and being movable in a direction generally parallel to said cylinder axis and generalLy transverse to the direction of any gas flow through said ports, to an opposite position in which all of said ports are open; means placing said ports, when open, in communication with the suction side of the compressor; control means for said air conditioner including means for effecting movement of said valve means in accordance with temperature changes in a selected range in the room conditioned by said air conditioner, said valve means moving progressively in a direction from said one position toward said opposite position in response to progressively lower temperatures in said range in said room, so that the compression stroke of said piston is, in effect, progressively shortened to provide progressively reduced capacity of said compressor while continuing to operate to provide reduced cooling and dehumidification of said conditioned room.