1. Field of the Invention
The present invention relates to a system for controlling oil seepage from a compressor. More particularly, the present invention concerns a system for diverting and collecting excess oil originating in the area of the shaft seal of the crankshaft of a reciprocating compressor.
2. Background Art
Refrigeration systems, such as the type used in transport refrigeration equipment, include, in the simplest form, a compressor, a condenser, an expansion device and an evaporator serially interconnected to form a closed refrigeration circulation path. Typically, such systems use a reciprocating type compressor that is lubricated by a lubricating oil which mixes with the refrigerant being compressed therein.
A typical reciprocating compressor includes a piston reciprocating within a cylinder for mechanically compressing gaseous refrigerant. Appropriate manifolds and valves are provided to allow gas to be drawn into the cylinder during the down stroke of the piston and to be compressed during the up stroke.
Oil is used in such compressors to lubricate the various parts and interfaces there between. To maintain refrigerant pressure within the compressor, mechanical shaft seals are used that deploy an oil film to seal against the leakage of pressurized gas and to lubricate the faces of the seal during operation. For example, such seals are used on the crankshaft of the compressor such as in the vicinity of the gland plate. Oil leakage across the seal faces is a common problem with any mechanical shaft seal. If such oil is allowed to leak unabated, external oil leakage through the crankcase can result. Typically such leakage is more visually unpleasing and alarming rather than detrimental to compressor function; however, such leakage often leads to unnecessary component replacement of the mechanical shaft seal components.
Accordingly, devices have been deployed to divert excess oil from the crankshaft seal area to hide external leakages. One such device is an external masking device used on an open-drive compressor known as the Bock FKX40/465. The device allows oil to leak to an external pocket, which is open to the atmosphere, on the outside of the gland plate and then utilizes an absorbent material to capture the excess oil over flowing therefrom. The absorbent material is encapsulated by a band of spring steel that is wrapped around the outside diameter of the material which is in turn wrapped around the gland plate housing in proximity to the external pocket.
While effective, these types of designs use an oil soaked external absorbent band which attracts dirt and can soil its surroundings, adding to the soiling of the external surfaces of the compressor.
It is an object of the present invention to reduce oil leakage in a device using shaft seals.
It is a further object of the present invention to provide an improved mechanism for diverting excess oil away from a shaft seal.
It is another object of the present invention to provide an improved mechanism for collecting excess oil after its diversion from a shaft seal.
It is another object of the present invention to provide a means for absorbing excess oil from the vicinity of a shaft seal.
It is still another object of the present invention to provide a means for providing external notice of excess oil absorbed from the vicinity of a mechanical shaft seal
These and other objects of the present invention are achieved according with the compressor oil diversion and collection system of the present invention, for use in a compressor having a housing, a crankshaft having shaft seals, refrigerant and a compression device for compressing the refrigerant. The system includes a shaft sealing mechanism that uses a lubricant for preventing compressor refrigerant from leaking out of the compressor housing and has a space where the lubricant collects. A diversion mechanism is deployed for directing excess amounts of the lubricant from the space to a receiver for receiving the excess amounts of said lubricant from the diversion mechanism. The receiver may be in the form of an internal cavity which includes a removable cartridge located in the cavity to collect the excess amount of lubricant, an external collection reservoir or an external drainage tube.