A device and method for extending the lifespan of a shaft seal for an open-drive compressor is provided. The device and method can also reduce and/or prevent deterioration of the shaft seal regardless of the operation condition of the open-drive compressor. The device and method can further reduce and/or prevent leakage of a lubricant and/or refrigerant that can cause deterioration of components within a transport refrigeration unit (TRU).

A compressor system can include a lubricant injection system useful to supply lubricant to an airend. The compressor system can include a variable lubricant flow valve which can be regulated by a controller on the basis of operating conditions of the compressor system. In one form the compressor system also includes an oil separator and/or an oil cooler with or without a thermal control valve. The controller can have one or more modes of operation, including a mode in which the controller regulates the flow of lubricant to the airend to increase an internal flow area of the valve when the airend is operated at an unloaded or loaded condition. In some forms the controller can regulate the lubricant flow valve and/or the thermal control valve and/or the lubricant cooler.

In the method according to the invention for operating an oil level regulator on a compressor, the oil level regulator monitors an oil level in the compressor and causes oil to be refilled when an oil deficiency is recognized. The oil level regulator provides operating recognition of the compressor in which a check is made as to whether the compressor is in a switched-on or switched-off state, the refilling with oil being carried out only when the compressor is in the switched-on state.

A method of operating a multiple-compressor refrigeration system is provided. This method includes the steps of supplying, via a common supply line, refrigerant gas and oil to a plurality of compressors coupled in series, and attaching an oil flow conduit between adjacent compressors of the plurality of compressors. The oil flow conduit is configured to move oil from a compressor with a relatively higher pressure to a compressor with a relatively lower pressure. The method further includes controlling the pressure for each of the plurality of compressors by regulating a speed at which each of the plurality of compressors operates in order to maintain a pressure differential between the adjacent compressors to facilitate the flow of oil from the compressor with the relatively higher pressure to the compressor with the relatively lower pressure.

The present disclosure provides a compressor system having at least one fluid compressor for compressing a working fluid. A lubrication supply system is operable for supplying lubrication fluid to the compressor. A closed loop cooling system using R718 refrigerant is provided to cool the working fluid. The closed loop cooling system includes a refrigerant compressor for compressing the refrigerant, a condenser operable for receiving compressed refrigerant gas and removing heat to form liquid refrigerant, and an expansion device for expanding and cooling the liquid refrigerant into a cooled gaseous refrigerant.

The present invention provides an oil feed type air compressor that can reduce a power consumption of a compressor body during an unload operation. The oil feed type air compressor includes: a compressor body (1) compressing air while feeding an oil into a compression chamber; a separator (4) disposed on a discharge side of the compressor body; a compressed air-feeding system (5) feeding the compressed air separated by the separator to a use destination of the compressed air; an oil-feeding system (6) feeding the oil separated by the separator to the compression chamber of the compressor body; an oil cooler (11) and a temperature sensor (12) disposed in the oil-feeding system; and a controller enabling execution of a temperature control. The temperature control by the controller is performed by variably controlling a rotation speed of a cooling fan (13) such that, during the load operation, a temperature detected by the temperature sensor is a target value T1, and during the unload operation, the temperature detected by the temperature sensor is a target value T2 (with the proviso of T1>T2).

The present disclosure provides a compressor system operable for compressing a working fluid such as air. A conditioner is positioned upstream of the compressor to reduce the humidity and in some embodiments may control a temperature of the working fluid entering the compressor. A working fluid aftercooler and a lubricant cooler is positioned downstream of the compressor. A first heat exchange system directs water from a source through the conditioner and then to the aftercooler and oil cooler in parallel. A second heat exchange system directs oil from the compressor to the oil cooler and then to a regenerator prior to reentry into the compressor. A control system with one or more control valves is configured to provide oil to the compressor at a target temperature defined to ensure that the temperature of the discharged compressor is above a pressure dew point temperature.

The present disclosure provides a compressor with an oil equalizing pipe, a parallel compressor set, and an oil equalizing method. The compressor includes at least one oil equalizing pipe, an opening at one end of the oil equalizing pipe is formed in a target oil level of an oil sump, and the opening at the other end of the oil equalizing pipe is formed in a suction port; and when the oil level of the oil sump of the compressor is higher than the target oil level, the extra oil enters the suction port through the oil equalizing pipe. Compared with the prior art, the present disclosure has the advantages that, when the compressor is running, the gas in the suction port flows, so that the pressure at the suction port is less than the pressure on the surface of the oil sump; when the oil level of the oil sump of the compressor is higher than the target oil level, the extra oil enters the suction port through the oil equalizing pipe under the action of the above pressure difference, a part of the oil enters vortex and is discharged from the compressor via the exhaust port, and the oil discharged from the compressor returns to the other compressor lack of oil through a pipeline, thereby achieving oil balance between different compressors.

An apparatus includes a suction header, a drain leg, an oil separator, and an oil reservoir. The suction header is configured to receive a refrigerant and the drain leg is coupled to the suction header. The oil separator is configured to separate an oil from the refrigerant from a compressor. During a first mode of operation, the drain leg is configured to collect an oil from the refrigerant from a compressor at the suction header. During a second mode of operation, the oil separator is configured to direct the oil separated from the refrigerant from the compressor through the drain leg and to the oil reservoir.

A multi-split system and a method and device for adjusting an oil volume of a compressor of a multi-split system. The adjusting method comprises the following steps: recycling oil back to an oil storage tank by controlling a switch unit to turn on and an oil volume adjusting unit to turn off; when a continuous time over which the oil storage tank recycles oil reaches a first pre-set time (t1), controlling the switch unit to turn off and controlling a multi-split system to perform a test run; obtaining, according to a low-pressure piping pressure loss (P1) and a refrigerant flow (Q), a low-pressure piping pipe diameter (D) and a low-pressure refrigerant density (Den), an excess oil volume (Q2) that needs to be recycled, and obtaining, according to the excess oil volume and a maximum oil storage volume (Qz) of the oil storage tank, an oil volume to be expelled (Q3).