A gearmotor assembly includes a housing, a rotatable shaft, a bearing, a retaining member, and a seal. The housing defines a gear chamber configured to contain a lubricant. The bearing rotatably supports the shaft. The bearing is disposed between the housing and the shaft. The retaining member at least in part restricts axial shifting of the bearing. The retaining member presents a plurality of retaining member threads. The housing defines a plurality of housing threads threadably engaging the retaining member threads. The retaining member and the housing cooperatively at least in part define an interface. The interface includes a threaded portion and an additional portion. The threaded portion is cooperatively defined by the retaining member threads and the housing threads. The additional portion is fluidly interconnected to the threaded portion. The seal is disposed along the interface to prevent lubricant escaping the gear chamber past the interface.

A rotor-chamber wall of a motor-driven Roots pump has a suction port and a discharge port. The side on which the discharge port is located with respect to a plane that includes both the rotational axis of a drive shaft and the rotational axis of a driven shaft is a first side. A first partition wall defines a gear chamber and has a first recess on the first side. A second partition wall defines the gear chamber and has a second recess. The first partition wall has a first oil supply passage that is configured to supply oil from the first recess to a first seal accommodating recess. The second partition wall has a second and a third oil supply passages. The second and the third oil supply passages are configured to supply oil from the second recess to a second and a third seal accommodating recesses, respectively.

An energy transfer machine includes a piston and cylinder. The piston can have a rocking motion as it enters and exits the cylinder, for example due to one being on a rotor and the other on a stator. The piston and cylinder form a primary chamber, and as they move relative to each other can form a seal separating the primary chamber into first and second sub-chambers which then unseals before the piston exits the cylinder. The first sub-chamber may reach a maximum geometric compression ratio, for example for the purpose of compression ignition, before the unsealing of the sub-chambers.

A rotary internal combustion engine having a cover plate, and stator plate having a bore with teeth and a primary cog that is larger than the teeth. A main rotor having a partially-circular cut-out. A gear rotor is disposed within the cut-out, having teeth that engage the teeth of the stator ring. A base plate has inlet ports for receiving fuel, air, and spark, where an ignition of the fuel and air by the spark creates a high pressure zone that drives the main rotor and the gear rotor rotationally within the stator ring, and an outlet port for exhausting spent fuel and air.

A gear wheel (10) for a hydraulic apparatus is rotatable about an axis of rotation (H-H) and comprises a plurality of teeth (11) having a sectional profile (P) and being adapted to mesh with respective teeth of another gear wheel during a rotational motion about the axis of rotation (H-H), wherein at least one tooth (11) is shaped so as to have at least one cutting edge (12) configured to remove material, in particular chips, from a body which is contacted by the cutting edge during the rotation of the gear wheel (10), wherein the cutting edge (12) is defined by at least one groove (14) which is lowered by amount from 0.2% to 5% of the height (H) of the tooth (11), said the groove (14) decreasing away from the cutting edge (12) along the profile (P).

A motor includes a housing, a shaft, a bearing, a bearing plate, and a seal. The housing includes first and second housing components directly engaging one another along a housing interface. The housing at least in part defines a sealed chamber. The shaft is at least in part received in the chamber. The bearing rotatably supports the shaft. The bearing plate is enclosed within the housing. The bearing plate supports the bearing within the housing. The seal is disposed along the housing interface. The bearing plate is spaced inwardly from the housing interface and the seal.

The present teachings include an energy recovery device usable in multiple applications, for example hydropower and vehicle power plant applications. In one aspect, an energy recovery device includes a housing having an inlet and an outlet in fluid communication with an internal cavity, and a pair of counter-rotating rotors having intermeshed lobes disposed within the housing internal cavity. Each rotor defines a transport volume between the housing and a pair of adjacent lobes and has a calculated maximum ideal twist angle below which the transport volume will be sealed from both the housing inlet and housing outlet. Each rotor also has an actual twist angle that exceeds the maximum ideal twist angle.

A motor includes a housing, a shaft, a bearing, a bearing plate, and a seal. The housing includes first and second housing components directly engaging one another along a housing interface. The housing at least in part defines a sealed chamber. The shaft is at least in part received in the chamber. The bearing rotatably supports the shaft. The bearing plate defines a bearing housing at least substantially receiving the bearing. The housing circumscribes the bearing plate such that the bearing plate is enclosed within the housing. The bearing plate is fixed to a supporting one of the housing components and directly engages the supporting one of the housing components along a bearing plate interface. The seal is disposed along at least one of the interfaces.

A pump particularly for pumping a liquid such as ink, paint, glue or the like, includes at least one rotating pumping member having a respective shaft. The at least one rotating pumping member being at least partially housed inside a pump body, the shaft being rotatably supported by at least one support associated with the pump body. The shaft has on its external cylindrical surface in contact with the liquid one, or more recesses, or the at least one support includes on its internal cylindrical surface in contact with the liquid, one or more recesses.

A compressor design includes a male rotor (10) having one or more helical lobes (12) and a female rotor (14) having one or more helical grooves (16). The male rotor is mounted on a first shaft and the female rotor is mounted on a second shaft. The male rotor is positioned in a first section of a chamber and the female rotor is positioned in a second section of the chamber. Fluid enters the chamber at an inlet, and when the rotors are driven, the lobes of the male rotor fit into the grooves of the female rotor, causing compression and movement of the fluid towards an outlet or discharge end where the compressed fluid is discharged. The configuration of the lobe and groove helix, the lobe and groove profile, and the outer diameter of the rotors can be varied in different combinations to form different rotors.