An electric liquid pump has a motor, a liquid pump including an inner rotor having an external tooth and integrated with an axial end of a shaft of the motor and an outer rotor having an internal tooth meshing with the external tooth and forming a gap, a motor case having a box shape and including therein first and second accommodation chambers and a partition wall allowing the first and second accommodation chambers to communicate with each other, and a body including a centering body portion, a general body portion, and a bearing portion formed to penetrate the centering body portion and the general body portion. The shaft is integrally formed with a sleeve of the shaft and a general shaft portion. The sleeve and the general shaft portion are made of the same material. The magnet portion is made of a bonded magnet and is integrated with the sleeve.

An electric liquid pump has a motor, a liquid pump including an inner rotor having an external tooth and integrated with an axial end of a shaft of the motor and an outer rotor having an internal tooth meshing with the external tooth and forming a gap into which a liquid is suctioned and from which the liquid is discharged, a motor case having a box shape and including therein a first accommodation chamber, a second accommodation chamber, and a partition wall allowing the first and second accommodation chambers to communicate with each other, and a body including a centering body portion, a general body portion, and a bearing portion formed to penetrate the centering body portion and the general body portion. The entire body is made of a thermosetting resin.

An electric liquid pump has a motor, a liquid pump including an inner rotor having an external tooth and integrated with an axial end of a shaft of the motor and an outer rotor having an internal tooth meshing with the external tooth and forming a gap into which a liquid is suctioned and from which the liquid is discharged, a motor case having a box shape and including therein a first accommodation chamber, a second accommodation chamber, and a partition wall allowing the first and second accommodation chambers to communicate with each other, and a body including a centering body portion, a general body portion, and a bearing portion formed to penetrate the centering body portion and the general body portion. The inner rotor or the outer rotor is made of a thermosetting resin.

A bearing block adapted for use in a gear pump assembly. The bearing block includes a bearing surface configured to face one or more gears. The bearing block further includes a bearing block body formed with a recess. The bearing block further includes an insert located within the recess. The insert includes an insert body including an outer surface. The insert body has a tapered shape that tapers outwardly from the bearing surface. The insert further includes a plurality of ridges disposed on the outer surface. The plurality of ridges defines one or more grooves therebetween. The recess includes a tapered shape complementary to the tapered shape of the insert body, such that the insert body engages with the bearing block body.

A pump assembly may include a drive mechanism and a rotatable shaft coupled to the drive mechanism. A pump may be carried by the rotatable shaft. The pump may include at least one pump stage for communication of a lubricant. A separator may be driven by the rotatable shaft. The separator may be operable to separate oil from a mixture of air and oil. A method of assembly is also disclosed.

A multi-stage compressor system for compressing a working fluid includes a compressor housing and a drive unit configured to drive a first shaft and a second shaft. The first shaft defines a first axis of rotation and the second shaft defines a second axis of rotation, where the first axis is parallel to the second axis of rotation. The compressor system further includes a first airend and a second airend operable to receive and compress the working fluid. The first airend includes a first rotor configured to be driven by the first shaft and a second rotor configured to be driven by the second shaft. The second airend further compresses the working fluid received from the first airend, and includes a third rotor configured to be driven by the first shaft and a fourth rotor configured to be driven by the second shaft.

Lobe pumps have bearing discs or caps which can be located at least partially in at least one of cover plates and rotors, if not both to provide at least thrust bearings to space the rotors from the cover plates while facilitating the possibility of clean in place operations. Many embodiments have bearing discs on the rotors which do not restrict axial movement on the shaft, but prevent pumped material from contacting the shaft, and many embodiments have bearing discs friction fit in bearing cutouts and bores (through the rotor and/or cover plate) to facilitate removal when disassembled.