An eccentric bush assembly structure of a scroll compressor, in which an orbiting scroll is eccentrically coupled to a rotary shaft of a drive motor, including a bush body rotatably coupled to the orbiting scroll while being pinned to the rotary shaft of the drive motor by an eccentric shaft, the bush body having a friction prevention groove formed in a surface facing a tip surface of the rotary shaft so as not to come into frictional contact with the tip surface.

A fluid pump includes a housing; an outlet; an inlet plate within the housing and having an inlet; an outlet plate disposed within the housing and having an outlet plate outlet passage; an electric motor which rotates about an axis; a pumping arrangement rotationally coupled to the electric motor such that rotation of the pumping arrangement causes fluid to be pumped from the inlet to the outlet plate outlet passage and through the outlet; a diverter plate between the outlet plate outlet passage and the electric motor and having a diverter passage which provides fluid communication from the outlet plate outlet passage, past the electric motor, to the outlet, the diverter plate also having an imperforate wall which is axially aligned with the outlet plate outlet passage such that the imperforate wall laterally directs fluid from the outlet passage to the diverter passage.

A screw pump has a male screw accommodation hole and a female screw accommodation hole formed in a pump housing. A male screw member and a female screw member are respectively accommodated in the male screw accommodation hole and the female screw accommodation hole. A male-side clearance is formed in a radial direction between the male screw member and the male screw accommodation hole and a female-side clearance is formed in the radial direction between the female screw member and the female screw accommodation hole. The female-side clearance is made to be larger than the male-side clearance, so that the female screw member can easily move in a direction away from the male screw member to the female-side clearance when any extraneous material is going to be wedged between the male screw member and the female screw member, to thereby prevent a locked condition of the screw members.

An apparatus and method prevent entrained solids from entering a pump by directing a process stream through an active upstream filter that removes the solids, and then through a downstream idle filter where the process stream purges the filter of previously retained solids. The flow path is periodically switched to exchange the roles of the filters, so that none of the filters is saturated, and the solids remain in the process flow but bypass the pump. Any need for a low pressure destination for purged solids and purging fluid and/or any environmental impact of dumping process fluid and solids into the environment is thereby avoided. Partially opened valves can be used to divert only part of the downstream flow for filter purging. Selectable paths can be included for which no filters are purged. The downstream flow can be divided and used to simultaneously purge a plurality of idle filters.

A stator for a helical gear device includes a first section having first helically convoluted chamber with a set of radially inwardly extending lobes and a second section adjacent to the first section. The second section includes a stack of cutter disks. Each cutter disk includes a front surface, a rear surface, an interior surface defining a central opening extending from the front surface to the rear surface, a forward cutting edge, and a rearward cutting edge. The interior surface forms a same number of lobes for the central opening as the set of radially inwardly extending lobes in the first section. Each cutter disk is aligned along a common centerline, and each cutter disk is rotated slightly relative to each other to form a second helically convoluted chamber with a same pitch as the first helically convoluted chamber. The second helically convoluted chamber exposes, to materials passing through, portions of the forward cutting edge or the rearward cutting edge of each cutter disk.

An air compressor as a fluid compressor includes: a suction port and a delivery port provided at upper and lower portions, respectively, of a pump chamber; a suction passage in communication with the inside of the pump chamber via the suction port; a delivery passage in communication with the inside of the pump chamber via the delivery port; and a driving rotor and a driven rotor provided in the pump chamber. At least a part of the suction passage is located below the suction port.

A rotary compressor includes: a vertically-positioned airtight compressor housing having an upper section including a discharge portion of a refrigerant, and a lower section including an inlet unit of the refrigerant and storing lubricant oil; a compressing unit, disposed in the lower section, compressing the refrigerant sucked in via the inlet unit and discharging the refrigerant from the discharge portion; a motor, disposed in the upper section, driving the compressing unit via a rotation shaft; and an accumulator attached to the compressor housing and connected to the inlet unit. Inside the accumulator and/or the compressor housing, silicon dioxide having a crystal structure containing a vacancy with a diameter equal to or less than a diameter of a water molecule or a composite including silicon dioxide having a crystal structure containing a vacancy with a diameter equal to or less than that of the water molecule is placed.

To overcome the problem associated with liquid or solid process debris from a vacuum process system falling into, and contaminating or damaging, a vacuum pumping arrangement used to evacuate the system, the inlet of the vacuum pumping arrangement is located lower than the outlet of the arrangement. This provides a net flow of gas pumped by the arrangement in a generally upwards direction thereby resisting the passage of contaminants into the arrangement.

Provided is a control device for a hydraulic control valve that can increase an efficiency of removing a foreign matter clogged in the hydraulic control valve. A control device controls a hydraulic control valve that controls a pump capacity of a variable displacement oil pump. The hydraulic control valve includes a sleeve and a spool valve that moves in the sleeve, and is configured to change a pump capacity by controlling an oil pressure by moving a spool valve between one end portion and the other end portion in the sleeve. The control device for the hydraulic control valve includes: a drive control unit that controls driving of the spool valve; and a determination unit that determines whether or not clogging of a foreign matter exists between a sleeve and the spool valve, and determines a position of the clogging of the foreign matter in a case where the foreign matter exists between a sleeve and the spool valve, and determines a position of the clogging of a foreign matter in a case where the clogging of a foreign matter exists.