Abstract: A valve for selectively allowing the return of oil from a discharge plenum to a suction plenum includes a passage which is selectively opened or blocked by a valve spool. The valve spool sees a pressure from a discharge pressure location upstream of a discharge check valve on one face, and a discharge pressure from a discharge plenum on an opposed face. While the compressor is running, the two pressures should be relatively equal. The face which sees the pressure from the chamber upstream of the check valve is larger than the face which sees the pressure from the discharge plenum. Thus, when the compressor is running, the valve spool is biased to a first position at which it allows oil return from the discharge plenum to the suction plenum. However, upon shutdown of the compressor, the pressure in the chamber upstream of the discharge valve drops. The valve spool will be driven to a second position at which it blocks communication for oil return.

Abstract: A spacer is positioned between an outer periphery of a motor stator, and the inner periphery of a center shell for a sealed compressor. The spacer allows a relatively small diameter motor to be used in a relatively large diameter center shell. The spacer includes a bearing mount in a lower plate, and a plurality of axially extending fingers positioned between the stator and the center shell. The spacer also includes a stop for proper positioning of the stator within the center shell.

Abstract: A scroll compressor is provided having appropriate clearance for movement of the orbiting scroll member. Clearance is provided without requiring contact between the crankcase, which supports the orbiting scroll, and the non-orbiting scroll member. Clearance is established during the assembly process using installation tooling that establishes locations of components using a reference point. Clearance is also established using spacers.

Abstract: A scroll compressor has a device which may be actuated to limit the orbit radius of the orbiting scroll. The device is moveable between an unactuated position at which it is spaced from a hub for the scroll compressor, and an actuated position at which it limits the orbit radius of the hub. The device may be actuated when reduced capacity is desired.

Abstract: A scroll compressor has a device which may be actuated to limit the orbit radius of the orbiting scroll. The device is moveable between an unactuated position at which it is spaced from a hub for the scroll compressor, and an actuated position at which it limits the orbit radius of the hub. The device may be actuated when reduced capacity is desired.

Abstract: A method of aligning a crankcase to a non-orbiting scroll includes the steps of forming initial alignment surfaces on both the non-orbiting scroll and the crankcase. Further, when the non-orbiting scroll and the crankcase are machined, precision drilled holes are drilled into each of the two. These holes are drilled relative to datum surfaces on both the non-orbiting scroll and the crankcase. Thus, once the two have been pre-positioned, the precision drilled holes are aligned and a threaded bolt is inserted into the precision drilled holes. The threaded bolt ensures that the two will be radially positioned properly relative to each other.

Abstract: A method of aligning a crankcase to a non-orbiting scroll includes the steps of forming initial alignment surfaces on both the non-orbiting scroll and the crankcase. Further, when the non-orbiting scroll and the crankcase are machined, precision drilled holes are drilled into each of the two. These holes are drilled relative to datum surfaces on both the non-orbiting scroll and the crankcase. Thus, once the two have been pre-positioned, the precision drilled holes are aligned and a threaded bolt is inserted into the precision drilled holes. The threaded bolt ensures that the two will be radially positioned properly relative to each other.

Abstract: A method of forming a drive surface on an eccentric pin of a drive shaft for a scroll-type compressor is provided. First, an eccentric pin having an axis and a generally cylindrical outer surface disposed radially about the axis is provided. Next, a broaching tool having a machining face with a contour is provided. The contour may be a concave shallow bell-shaped curve. Finally, the drive surface is formed by engaging the outer surface with the machining face transverse to the axis. In this manner, the machining face forms a shape complementary to the contour on the eccentric pin thereby forming a slight crown on the drive surface. The broaching tool produces an adequate surface finish so that no subsequent machining operations to the drive surface are necessary.

Abstract: A scroll compressor has a recess communicating with a back pressure hole leading to a back pressure chamber. The recess may be formed in either the rear face of the orbiting scroll, or in the mating face of the crankcase. Preferably, the recess surrounds the orbiting axis of the orbiting scroll compressor, and may be circular. The recess serves to quickly supply fluid from the back pressure hole to the back pressure chamber. This is particularly valuable at startup of the scroll compressor. With the inventive recess, a test to determine whether the scroll compressor is capable of reaching its operative pressures may be performed more quickly and more accurately. The recess is preferably relatively shallow, and is preferably of a depth which is less than the diameter of the back pressure hole.

Abstract: The outer surface of a slider block increases radially with increasing distance from the crankshaft for at least a portion of its height. As a result when the drive pin of the crankshaft deflects under load the slider block moves therewith as a unit. The surface of the slider block maintains an essentially uniform oil film thickness over an extended area due to its shape.

Abstract: The reversing of the direction of rotation of the motor of a fixed vane rotary compressor reverses the direction of rotation of the rolling piston. The rolling piston through viscous friction or frictional torque frictionally engages a reversing disk and causes the reversing disk to move between two positions depending upon the direction of rotation of the rolling piston. The reversing disk has a slot therein which forms the suction inlet and is moved by rotation of the reversing disk so as to be in fluid communication with the plenum which is serving as the suction plenum at that time.

Abstract: A skeleton structure for a free standing wall type or a gondola type fixture assembly, comprising modular base units secured successively to each other as a base structure by uprights of framing for selectable superstructure. A modular primary base unit, of generally hollow rectangular plan form, fabricated with inward top and bottom flanges from sheet-metal shallow channel stock, with the channel vertical web providing panel-like unit sides, has like vertical half-sockets of rectangular cross-section located on respective central webs of two opposite sides, with the top flange notched above each half-socket, the half-sockets being located centrally of the base sides for island fixtures or at back corners of half-base units for wall type fixtures.