Abstract: A pump may generally include a frame including a reservoir. The reservoir stores a hydraulic fluid. The pump may also include a motor assembly supported by the frame and a pump assembly operably driven by the motor assembly. The pump assembly is in fluid communication with the reservoir and configured to dispense the hydraulic fluid out of the frame. The pump assembly includes a first piston and a second piston, wherein the first piston dispenses hydraulic fluid out of the frame between a first pressure and a second pressure greater than the first pressure, and the second piston dispenses hydraulic fluid out of the frame between the first pressure and a third pressure, the third pressure being greater than the second pressure.

Abstract: The multistage dry vacuum pump is disclosed, in which it is possible to prevent a pump from being adhesively stuck, which problem occurs due to a difference in thermal expansions between a cylinder body and a rotor, by making thermal expansion conditions between a cylinder body and a rotor of a pump similar by concurrently cooling the cylinder body and the rotor of the pump, and a high vacuum degree can be obtained by obtaining an optimum gap design in the rotor and the cylinder, respectively, for thereby making the size of the pump smaller and significantly reducing the maintenance cost of the pump facilities.

Abstract: A system for continuous delivery of a measured flow of liquid to a processing apparatus includes a reservoir for holding a bulk supply of the liquid and an intermediate vessel. A first pump delivers liquid from the intermediate vessel to processing equipment at one rate. A second pump delivers liquid from the reservoir to the intermediate vessel at a second much faster rate. A monitor device continuously monitors the weight of the vessel and controls the first pump accordingly to deliver the required weight of liquid at the required rate to the processing equipment. The monitoring device determines when the weight of liquid in the intermediate vessel has reached a minimum position to initiate operation of the second pump to refill to vessel and a further device terminates operation of the second pump when the liquid level in the vessel reaches a maximum position.

Abstract: A piston sealing ring assembly (70) for sealing the piston/cylinder interface of a double-acting gas compressor including a first and second cut piston sealing ring (54,72) each bounded by first and second planar surfaces (6,8), the first piston sealing ring (54) having an overlapped cut with generally circumferentially extending inner and outer overlapping portions (56,58) which contact each other to form a continuous seal extending from the first surface (6) to the second surface (8) of the first piston sealing ring (52) and separating an inner ring gap (62) from an outer ring gap (64). The periphery of the outer ring gap (64) of the first piston sealing ring (54) at the first surface (6) is sealed by the second surface (8) of the second piston sealing ring (72). The second piston sealing ring (72) is similarly disposed in relation to the first piston sealing ring (54) so its outer ring gap (64) is sealed at the second surface (8) by the first surface (6) of the first piston sealing ring (54).

Abstract: A primary compressor and a booster compressor connected in series is presented. A first conduit connects the low side of a heating/cooling or refrigeration system to the inlet of the booster compressor, the outlet of the booster compressor and the inlet of the primary compressor. A second conduit connects the outlet of the primary compressor to the high side of the system. The first conduit includes a check valve for closing or opening the connection between the first conduit and the outlet of the booster compressor. A sump conduit is positioned near the bottom of the primary and booster compressors to allow lubricant to flow from the booster compressor to the primary compressor.

Abstract: A fuel pumping apparatus comprises feed pump supplying fuel to an injection pump. A chamber is located between the two pumps and has an outlet including a restricted orifice extending from the upper end of the chamber through which fuel and air collecting in the chamber can flow. A float is located in the chamber and mounts a valve member which can cooperate with a seating defined about a lower outlet in the lower wall of the chamber. The lower outlet connects with the injection pump and is obstructed if the chamber becomes filled with air to prevent the supply of air to the injection pump.

Abstract: A floor-ceiling air circulating device includes a base adapted to be supported on the floor of a room, a duct assembly extending vertically from the base and defining a flow path between an upper outlet adjacent the ceiling of the room and a lower inlet adjacent the floor of the room and a flow path between an upper inlet near the ceiling and a lower outlet near the floor, and a fan associated with each flow path and housed in the base to stabilize the device. One of the fans draws air from the floor and discharges the air at the ceiling via one flow path and the other fan draws air from the ceiling via the other flow path and discharges the air at the floor such that the air drawn from the floor is replaced with air drawn from the ceiling and vice versa to thereby circulate the air at the floor and at the ceiling and reduce temperature stratification in the room.

Abstract: In accordance with the invention there is provided an extracorporeal blood circulation system including a drip chamber having a blood inlet in its top and a blood outlet in its bottom, such chamber during operation containing blood in its bottom portion and air in its top portion, an air passage communicating with the top of the chamber, an air pump communicating with the atmosphere and with the passage for pumping air through the passage from the chamber into the atmosphere and from the atmosphere into the chamber, and means for selectively actuating the pump to either pump air into or out of the chamber.