The present invention relates to improvements in the area of flexible impeller pumps. In particular, the present invention relates to flexible impellers with improved profiles(such as dual sealing lips), which are particularly well-suited to multiple cam pumps. A novel mounting hub configuration for mounting an impeller on a drive shaft is also provided. Pumps comprising such impellers and/or mounting hubs are provided, as are associated methods of installation and removal.

A sliding vane, positive displacement pump is provided which includes a dual mechanical seal that protects against leakage from a pump chamber while also reducing slip across rotor end faces. The dual mechanical seal may be formed as a cartridge seal that is readily demountable from the pump for replacement and service, and is retrofittable to existing pumps to improve the performance thereof. The pump may integrally include a dual mechanical seal, or the mechanical seal assembly may be provided for use by itself or in combination with a replaceable head ring that can be installed on existing pumps for repair thereof or for a retrofit upgrade of such existing pump.

A rotary piston machine includes a casing and a rotor assembly, each with a hypotrochoidal. The rotor assembly includes apices that conform to the hypotrochoidal profile of the casing, and the relative motion of the casing and the rotor assembly create variable volumes. The variable volume allows the rotary piston machine to function as a compressor, an expander, an internal combustion engine, a positive displacement pump, or a fluid-driven motor.

A working oil chamber sealing system of a rotary vane steering gear actuator having a top end face of a respective segment of a housing that holds a segment top face horizontal seal. The segment top face horizontal seal having a sealing face which touches a rear face of a top cover. The top cover rear face holds an upper ring seal, a sealing face of which touches an outer circumferential edge of an upper end face of a rotor and also touches a sealing face inner edge of the segment top face horizontal seal and a sealing face inner edge of an upper horizontal vane seal of a rotor vane, respectively.

The disclosure provides a method of oil delivery to a chainsaw chain blade using a gerotor pump in sequence with flow control valves to provide lubrication to the chain blade to reduce friction with the chainsaw bar guide and prevent overheating and damage to the chain blade or guide bar.

A variable displacement vane pump includes: an adapter ring (a cam ring housing member) that defines a first fluid pressure chamber and a second fluid pressure chamber relative to an outer periphery of a cam ring, the cam ring being moved relative to a rotor by a differential pressure between the first fluid pressure chamber and the second fluid pressure chamber; a seal housing groove formed in an inner periphery of the adapter ring; and a slipper seal which is inserted into the seal housing groove and with which an outer periphery of the cam ring comes into sliding contact when the cam ring moves, whereby the slipper seal partitions the first fluid pressure chamber from the second fluid pressure chamber, wherein the slipper seal is formed in a thin plate shape having a square cross-section.

The present invention relates to improvements in the area of flexible impeller pumps. In particular, the present invention relates to flexible impellers with improved profiles (such as dual sealing lips), which are particularly well-suited to multiple cam pumps. A novel mounting hub configuration for mounting an impeller on a drive shaft is also provided. Pumps comprising such impellers and/or mounting hubs are provided, as are associated methods of installation and removal.

A rotary piston machine includes a casing and a rotor assembly, each with a hypotrochoidal. The rotor assembly includes apices that conform to the hypotrochoidal profile of the casing, and the relative motion of the casing and the rotor assembly create variable volumes. The variable volume allows the rotary piston machine to function as a compressor, an expander, an internal combustion engine, a positive displacement pump, or a fluid-driven motor.