An air boost system for a two-cycle engine, such as an EMD engine, which operates with one or more roots blowers, or for similar engines that use gear-driven roots blowers or centrifugal blowers. At least one of the roots blowers is equipped with a variable transmission, which allows airflow into the engine to be varied in accordance with load or other engine operating conditions.

A dry vacuum pump may include a stator which defines an internal chamber in which a rotor is rotationally mounted. A sensor is mounted to the stator and has an output connected to a processing circuit arranged to analyse the output of the sensor to determine the absolute distance between a point on the surface of the rotor and internal stator surface. The rotor to stator clearance can thus be accurately determined in real time during operation of the pump, so that the pump performance can be optimised over its serviceable life.

A dry vacuum pump may include a stator which defines an internal chamber in which a rotor is rotationally mounted. A sensor is mounted to the stator and has an output connected to a processing circuit arranged to analyse the output of the sensor to determine the absolute distance between a point on the surface of the rotor and internal stator surface. The rotor to stator clearance can thus be accurately determined in real time during operation of the pump, so that the pump performance can be optimised over its serviceable life.

Volumetric compressor (1) for collection and/or treatment equipment of material in liquid, solid, dusty or muddy form. The compressor (1) comprises an operative chamber (50), defining a suction section and an exhaust section of a first fluid, a first header (61) and a second header (62), which delimit said chamber (50) on opposite parts along a longitudinal axis (101). The compressor further comprises at least two rotors (80, 80) with lobes (81, 81) housed in the chamber (50), each rotor (80, 80) rotating about a rotation axis (108, 108) substantially parallel to said longitudinal axis (101). The lobes of each rotor develop according to a helical profile. Furthermore, each of the headers (61, 62) defines at least one injection opening (71, 71, 72, 72) communicating with a feeding device (150) of a second fluid.

A multistage pump body comprises a first pumping chamber (20) and a second pumping chamber (21). A connecting duct (26a) puts an outlet (27) of the first pumping chamber (20) into communication with an inlet (28) of the second pumping chamber (21). A leak-tight conduit (40) is provided for the circulation of a cooling liquid. The connecting duct (26a) is a lateral duct of the multistage pump body. A heat-conducting wall (33) partially delimits the connecting duct (26a) and has an external surface (34) on the outside. At least a portion of the connecting duct (26a) passes between this external surface (34) of the heat-conducting wall (33) and the leak-tight conduit (40).

A supercharger constructed in accordance to one example of the present disclosure includes a housing, a first rotor, a second rotor, a first timing gear, a second timing gear, a first rotor shaft, a second rotor shaft and a coupling. The first and second rotors are received in cylindrical overlapping chambers of the housing. The first timing gear has a gear body that includes first helical teeth. The gear body further defines a central bore and a series of openings. The second timing gear has second helical teeth and is arranged in meshed engagement with the first timing gear. The first rotor shaft supports the first rotor and the first timing gear. The second rotor shaft supports the second rotor and the second timing gear. The coupling has a coupling body and includes a series of protrusions configured to be inserted into the series of openings of the gear body.

An EGR pump system includes an EGR pump assembly including an electric motor assembly coupled to a transmission assembly. A roots device is coupled to the electric motor through the transmission assembly. The roots device includes a housing defining an internal volume and rotors are disposed in the internal volume and connected to the transmission assembly. An EGR locking mechanism is attached to the EGR pump assembly. The EGR locking mechanism is selectively connected to the transmission assembly locking the transmission assembly and preventing rotation of the rotors.

A claw pump includes: a housing; two rotating shafts which are disposed parallel; a pair of rotors respectively fixed to the two rotating shafts; a rotary drive device driving the pair of rotors; and a suction port and discharge ports formed in a partition wall of the housing. The discharge ports are constituted by a first discharge port and a second discharge port. The first discharge port is formed at a position that communicates with an initial stage compression space formed at an initial stage of a compression stroke in a compression space that is formed by joining a first pocket and a second pocket. The claw pump includes an opening/closing mechanism which opens the first discharge port when a pressure of the initial stage compression space reaches a threshold and closes the first discharge port when the pressure does not reach the threshold.

A claw pump includes: a housing; two rotating shafts which are disposed parallel; a pair of rotors respectively fixed to the two rotating shafts; a rotary drive device driving the pair of rotors; and a suction port and discharge ports formed in a partition wall of the housing. The discharge ports are constituted by a first discharge port and a second discharge port. The first discharge port is formed at a position that communicates with an initial stage compression space formed at an initial stage of a compression stroke in a compression space that is formed by joining a first pocket and a second pocket. The claw pump includes an opening/closing mechanism which opens the first discharge port when a pressure of the initial stage compression space reaches a threshold and closes the first discharge port when the pressure does not reach the threshold.

A supercharger assembly comprises a housing, a rotor bore with an outer wall, an outlet in an outlet plane, an inlet in an inlet plane perpendicular to the outlet plane, and an outlet divider wall. The supercharger assembly comprises a first recess, a first perforated material covering the first recess, and an outlet resonator. The first recess is separated from the outlet by the outlet divider wall. The first recess is located between the outer wall and the first perforated material.