Abstract: A compressor includes a male rotor (26) having a screw-type boy portion (30) extending from a first end (31) to a second end (32) and held within a housing assembly for rotation about a first rotor axis (500). A female rotor (27, 28) has a screw-type female body portion (33, 34) meshed with the male body portion and extending from a first end (35, 36) to a second end (37, 38) and held within the housing assembly for rotation about a second rotor axis (501, 502). An end seal (120) has a first surface (126) engaging the female body portion first end and being asymmetric around the second axis.

Abstract: The area of the discharge end of a screw rotor acted on by the discharge pressure is reduced by locating a region of suction pressure acting on the discharge end of the rotor and separating the suction and discharge pressures by a labyrinth seal located between the discharge end of the rotor and the facing housing structure.

Abstract: The inlet bearings of a screw machine, such as a refrigerant compressor, are both lubricated and cooled by a portion of the motor cooling and suction flow which has lubricant entrained therein and which is drawn through the inlet bearings into the coacting pair(s) of screw rotors.

Abstract: Two slide valves are located in the discharge end bearing case of a multi-rotor screw machine and independently coact with the sun rotor of the multi-rotor screw machine for controlling capacity and Vi. Movement of the slide valves is in a plane perpendicular to the axis of the sun rotor.

Abstract: An unbiased valve is located within a muffler. The valve is positioned by the pressure differential across the valve and is either in the full open or full closed position. A pressure equalization tube is provided between the downstream cavity of the muffler and the back of the valve such that flow pattern produced low pressure areas are avoided and the valve can react to actual pressure differentials in the flow.

Abstract: Provision is made for stacking one condenser on another by mounting apparatus which includes a channel for receiving and supporting the existing feet at the base of the upper unit, and a clip member for securing the combination to the lower edge of the lower unit cover. Where the upper and lower units are the same size, a single fastener attaches both the feet and the clip to the channel. Where the upper unit is smaller than the lower unit, separate fasteners are applied to secure the feet to the channel and to secure the channel to the clip.