Rotary positive displacement pump having a one-piece drive housing provided with an opening with a closing cover and with bearing seats engaging at least one bearing, wherein a primary drive shaft and a secondary drive shaft are each rotationally engaged to the bearings of the opposite bearing seats of their own axis, each drive shaft being provided with at least one gear which is interposed between the opposite bearing seats, and wherein each drive shaft engages a positive displacement screw rotor placed within a stator body, the positive displacement screw rotors being intended to enable the generation of a product flow between a product inlet duct and a product outlet duct with which the product section is provided, and wherein the gears are monolithic and at least one of the gears is keyed to the drive shaft by a keying device for hollow shafts.

A main bearing housing assembly for a scroll compressor and a scroll compressor having the main bearing housing assembly. The main bearing housing assembly comprises: a main bearing housing; and a thrust plates, the thrust plate being provided at the top of the main bearing housing, and comprising a thrust surface located at the top and in surface contact with the bottom end surface of a scroll assembly of the scroll compressor; the thrust plate comprises: at least one oil inlet hole; a closed oil chamber, the closed oil chamber being formed in the thrust plate; and at least one oil outlet hole, the opening of the at least one oil outlet hole being exposed to the thrust surface; and the at least one oil inlet hole is in communication with the at least one oil outlet hole by means of the closed oil chamber.

A main bearing housing assembly for a scroll compressor and a scroll compressor having the main bearing housing assembly. The main bearing housing assembly comprises: a main bearing housing; and a thrust plates, the thrust plate being provided at the top of the main bearing housing, and comprising a thrust surface located at the top and in surface contact with the bottom end surface of a scroll assembly of the scroll compressor; the thrust plate comprises: at least one oil inlet hole; a closed oil chamber, the closed oil chamber being formed in the thrust plate; and at least one oil outlet hole, the opening of the at least one oil outlet hole being exposed to the thrust surface; and the at least one oil inlet hole is in communication with the at least one oil outlet hole by means of the closed oil chamber.

A gas-liquid separator and method and air compressor system. The gas-liquid separator includes a separator tank having wet side and dry side chambers. The wet side chamber separates and collects liquids from pressurized air that enters through a tank inlet. A separation valve inlet port connects the wet side chamber with the dry side chamber and allows moist air to pass from the wet side chamber to the dry side chamber and prevents collected liquids from passing from the wet side chamber to the dry side chamber. A separation valve assembly opens the separation valve inlet port when pressurized air is forced into the wet side chamber and a pressure is met and/or exceeded and to close the separation valve inlet port when pressurized air is not being forced into the wet side chamber and pressure falls below the pressure.

A dry vacuum pump includes: at least one oil sump; at least one pumping stage; two rotary shafts respectively supporting at least one rotor extending into the at least one pumping stage, the rotors being configured to rotate in a synchronized manner in the reverse direction in order to convey a gas to be pumped between an intake and an outlet of the vacuum pump, the shafts being supported by bearings lubricated by a lubricant contained in the at least one oil sump; at least one lubricant sealing device interposed between the at least one oil sump and a pumping stage at the shaft passage; and at least one expansion device configured to reduce the pressure variations between a pumping side volume and the at least one oil sump.

A dry vacuum pump includes: at least one oil sump; at least one pumping stage; two rotary shafts respectively supporting at least one rotor extending into the at least one pumping stage, the rotors being configured to rotate in a synchronized manner in the reverse direction in order to convey a gas to be pumped between an intake and an outlet of the vacuum pump, the shafts being supported by bearings lubricated by a lubricant contained in the at least one oil sump; at least one lubricant sealing device interposed between the at least one oil sump and a pumping stage at the shaft passage; and at least one expansion device configured to reduce the pressure variations between a pumping side volume and the at least one oil sump.

A vane rotary compressor may include a main bearing and a sub bearing provided with a plurality of back pressure pockets each having a different pressure formed on a surface facing the cylinder, a rotational shaft radially supported by the main bearing and the sub bearing, a roller provided with a back pressure chamber that communicates with the plurality of back pressure pockets and having a plurality of vanes configured to divide a compression space into a plurality of compression chambers. At least one of the main bearing or the sub bearing is provided with an oil supply passage that communicates with a back pressure pocket having a relatively low pressure among the plurality of back pressure pockets. Accordingly, oil may be smoothly supplied to a back pressure pocket having a low pressure.

A method for monitoring an oil-injected screw compressor configured to compress aspirated air by returning oil from an oil separator vessel (11) to a compression chamber (12) of a compressor block (30), for condensate formation in the oil circuit due to a too low compression discharge temperature (VET), determines a water inlet mass flow {acute over (m)}.sub.ein(t) and a water outlet mass flow {acute over (m)}.sub.aus (t) for a point in time t and determines generated condensate flow Δ{acute over (m)}.sub.w (t)={acute over (m)}.sub.ein(t)−{acute over (m)}.sub.aus (t) on the basis of difference formation.

A dry vacuum pump is provided, including an oil sump; a pumping stage; two rotating shafts respectively holding a rotor extending in the pumping stage, the rotor being configured to rotate in a synchronised manner in opposite directions in order to carry a gas to be pumped between an intake and a discharge of the pump, the two rotating shafts being supported by bearings lubricated by a lubricant contained in the oil sump; and a lubricant sealing device inserted between the oil sump and a pumping stage at each shaft passage, the sealing device including a disc-shaped deflector mounted on a shaft of the two rotating shafts for rotation therewith, and a disc of the deflector has an annular end on a periphery thereof, extending towards the pumping stage, forming a retaining recess.

A climate-control system may include a compressor, a condenser, an evaporator, a first sensor, a second sensor, a third sensor, and a control module. The compressor may include a motor and a compression mechanism. The condenser receives compressed working fluid from the compressor. The evaporator is in fluid communication with the compressor and disposed downstream of the condenser and upstream of the compressor. The first sensor may detect an electrical operating parameter of the motor. The second sensor may detect a discharge temperature of working fluid discharged by the compression mechanism. The third sensor may detect a suction temperature of working fluid between the evaporator and the compression mechanism. The control module is in communication with the first, second and third sensors and may determine whether a refrigerant floodback condition is occurring in the compressor based on data received from the first, second and third sensors.