A two-stage screw compressor and an air conditioning system. The two-stage screw compressor includes: a housing with an intake port and an exhaust port provided thereon; a low-pressure stage screw set axially arranged in the housing and connected to the intake port; a high-pressure stage screw set axially arranged in the housing and connected to the exhaust port; a drive motor axially arranged in the housing; and a transmission gear set for simultaneously transmitting a torque provided by the drive motor to the low-pressure stage screw set and the high-pressure stage screw set; wherein, the drive motor, the low-pressure stage screw set and the high-pressure stage screw set are axially arranged on the same side of the transmission gear set.

An engine fuel control system includes a main pump which receives fuel from a low pressure source and delivers the fuel at a first high pressure, and a variable displacement augmenter pump which receives fuel from the low pressure source and delivers the fuel at a second high pressure. The augmenter pump has a servo-controller to vary its pump flow rate. The system includes an augmentation valve which is actuatable by an electrically operated control valve to open a flow path therethrough which diverts fuel delivered by the augmenter pump or to shut the flow path. The system includes a pressure drop control valve which senses a pressure differential between the second high pressure and a reference pressure, and controls the servo-controller to vary the pump flow rate of the augmenter pump. The pressure drop control valve spills some of the fuel delivered by the augmenter pump.

A compressor system includes: a first compressor including a first casing having a cylindrical shape, and a first bundle capable of being inserted into and pulled out from the first casing in an axial direction of the first casing; and a second compressor including a second casing having a cylindrical shape, and a second bundle capable of being inserted into and pulled out from the second casing in an axial direction of the second casing. The first and second compressors are arranged to face each other to cause pullout directions of the respective bundles to be opposite to each other. A maintenance space shareable for insertion and pullout operations of the first bundle and insertion and pullout operations of the second bundle is interposed between the first bundle and the second bundle, and is available for the bundle under the insertion and pullout operations.

The present invention relates to a pumping system to generate a vacuum (SP), comprising a main vacuum pump which is a dry screw pump (3) having a gas suction inlet (2) connected to a vacuum chamber (1) and a gas discharge outlet (4) leading into a gas evacuation conduit (5) in the direction of a gas exhaust outlet (8) outside the pumping system. The pumping system comprises a non-return valve (6) positioned between the gas discharge outlet (4) and the gas exhaust outlet (8), and an auxiliary vacuum pump (7) connected in parallel to the non-return valve. In a pumping method by means of this pumping system (SP), the main vacuum pump (3) is started up in order to pump the gases contained in the vacuum chamber (1) and to discharge these gases through its gas discharge outlet (4), simultaneously to which the auxiliary vacuum pump (7) is started up. Moreover the auxiliary vacuum pump (7) continues to pump all the while that the main vacuum pump (3) pumps the gases contained in the vacuum chamber (1) and/or all the while that the main vacuum pump (3) maintains a defined pressure in the vacuum chamber (1).

A pump includes a first housing part defining a first portion of a bore extending within the first housing part and shaped to receive a rotor; and a second housing part defining a second portion of the bore extending within the second housing part and shaped to receive the rotor. The first housing part has a first face abutable against an opposing second face of the second housing part to position the first portion of the bore with the second portion of the bore to receive the rotor. The first portion of the bore has a first circular cross-section portion centered along the first face and the second portion of the bore having a second circular cross-section portion centered, within the second housing part, at a distance from the second face.

A system for protecting an engine from damage due to vibration while the engine is not operating is provided. The system includes an engine having a crankshaft, at least one piston, at least one bearing, a lubricating fluid source, and a fluid pump associated therewith and a controller operationally connected to and configured to control the fluid pump. When the system is in a first mode, the controller is configured to control the fluid pump in a duty cycle to maintain a predetermined minimum fluid pressure of the lubricating fluid such that a lubricating fluid film is present between the at least one bearing and the crankshaft while the engine is not operating.

A fuel system for a turbomachine includes a fuel tank and a first fuel line in fluid communication with the fuel tank and one or more fuel injectors. The first fuel line includes a main fuel pump disposed on the first fuel line, and an electric metering system disposed on the first fuel line downstream of the main fuel pump configured for starting the turbomachine and metering fuel to the fuel injectors.

A fuel system includes a fuel gathering system in fluid communication with a fuel storage container, and a fluid pump assembly in fluid communication with the fuel gathering system. The fluid pump assembly includes a main gear pump stage and a first flow attenuator. A main driven gear is meshed with a main drive gear in a main pump conduit, and a main pump bearing assembly rotatably supports the main drive gear and the main driven gear. The first flow attenuator is disposed around the main pump conduit, and includes a substantially polygonal fluid opening. Edges of the opening are substantially aligned with an undercut bearing portion on at least one of an inlet side and an outlet side of the main pump conduit to define a non-round fluid boundary.

A personal formulation device for mixing and dispensing customized formulations from ingredient reservoirs carried by the device. The device may include a plurality of miniaturized progressive pumps with a flexible coupling between the motor and the pump. The coupling may include a spring (40). The device may include a spacer sleeve (62) having an internal diameter tapered to closely follow the motion envelope of the spring (40). Each pump may include a retainer (60) that is threaded into the interior of the pump body (52) to retain the spacer sleeve (62) and the drive end (120) of the rotor (34). Each pump may include a stator with an integrated flange seal (36). The flange seal (36) may extend around the circumference of the stator and be sandwiched between portions of the pump body (52). The stator may have a noncircular shape that keys the stator within the pump body. The pump may include an optical metering system.

A linear actuator system includes a linear actuator and at least one proportional control valve and at least one pump connected to the linear actuator to provide fluid to operate the linear actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.