Abstract: A hydraulic device for pumping molten metal and/or controlling its flow, comprising an enclosure that forms internally a cylindrical chamber, for the connection of at least one first duct and one second duct for the passage of molten metal, within which a piston can slide hermetically in order to pump and/or control flow, an insulating cushion of inert gas being interposed between the piston and the molten metal, the piston being associated with an actuator for moving it with a reciprocating rectilinear motion.

Abstract: The invention relates to a water-injected screw compressor, comprising a compressor element (2) with a housing (7) which borders a compression chamber (8) in which two rotors (9, 10) are installed, which, by means of an axle ends (13, 14; 15, 16), are borne in the housing (7) by means of water-lubricated slide bearings (1), an electric motor (3) comprising a housing (18) which carries a stator (19) at the inside, which stator surrounds a rotor (21) with a rotor shaft (22). An axle end (13) of one of the rotors (9) is directly coupled to or forms one piece with the rotor shaft (22) of the motor (3), said rotor shaft being located in the prolongation of said axle end. The rotor shaft (22) of the motor (3) is borne in at least one water-lubricated slide bearing (23).

Abstract: A compressor system that is configured to compress the fluid from low pressure source to a higher pressure magnitude is powered from the same low pressure fluid source. The compressor system includes two piston assemblies that are coaxially coupled to one another, and that are of differing cross sectional areas. The low pressure fluid is used to move the larger piston assembly, which is in turn used to move the smaller piston assembly. Low pressure fluid is selectively admitted to the smaller piston assembly, and movement thereof is used to compress the low pressure fluid to a higher pressure magnitude. The compressor system uses a fluidic bistable amplifier, which also coupled to the low pressure fluid source, to control low pressure fluid flow to the larger piston assembly, to thereby control its movement.

Abstract: A check valve is provided to each discharge port, which communicates between a corresponding working chamber and a high pressure chamber in an integrated compressor/expander apparatus. A valve mechanism, which is opened in a motor mode, is provided to communicate between the working chamber and the high pressure chamber.

Abstract: A variable displacement pump includes a control valve formed with a high-pressure chamber for introducing therein high-pressure fluid on the upstream side of a metering orifice, a pressure chamber for introducing therein pressure fluid on the downstream side of the metering orifice, a low-pressure chamber arranged between the high-pressure and pressure chambers for introducing therein low-pressure fluid, and a communication passage for providing fluid communication between one of the high-pressure and low-pressure chambers and a first fluid-pressure chamber of the pump.

Abstract: A fluid pump assembly is used in combination with a container having a wall. The pump assembly comprises a first casing disposed outside the container in contact with the wall, a first magnetic assembly mounted to the first casing and operatively associated with a drive motor, a second casing disposed inside the container in contact with the wall, and a second magnetic assembly mounted to the second casing and operatively associated with an propeller. The first magnetic assembly includes a rotatable magnetic drive member drivingly coupled to the drive motor. The magnetic drive member is magnetically coupled to the magnetic driven member through the wall for imparting a rotary driving force of the drive motor to the propeller. Furthermore, the second casing is detachably connected to the second side of the wall of the container solely by magnetic attraction force between the first and second magnetic assemblies.

Abstract: A multi-stage compressor is disclosed, which comprises: two motion converters driven by one driving shaft and converting a rotary motion to a straight-line reciprocating motion; first and second pistons (62) connected to one of the motion converters in opposite directions and moving reciprocatively in a straight line; and third and fourth pistons (72) connected to the other one of the motion converters in opposite directions, arranged at a predetermined angle with respect to the first and second pistons (62), and moving reciprocatively in a straight line, and which is characterized in that at least two of the four pistons operate for first-stage compression and at least one of the others operate for second-stage compression.

Abstract: In a hermetic compressor in a freezing refrigerating system or an air-conditioning system such as a refrigerator or a showcase, a construction is disclosed for intending to provide a low-noise hermetic compressor by effectively attenuating a pressure pulsation having occurred in a compression chamber with a suction muffler. By this construction, since a muffler cover 20 has a planar simple shape, the deformation upon molding becomes little and it can come into fully close contact with a muffler main body 19. Therefore, the pressure pulsation hardly leaks through the connecting portion between the muffler main body 19 and the muffler cover 20. The full silencing effect that the suction muffler 18 has is obtained and thereby noise can be reduced more effectively.

Abstract: A power transmission mechanism for transmitting driving power between a shaft and a rotor connected to the shaft includes a cylindrical adapter located between the shaft and the rotor and a screw seat arranged on the shaft. The adapter has a first internally threaded portion in its inner peripheral surface and a first externally threaded portion in its outer peripheral surface. The first internally threaded portion is engaged with a second externally threaded portion of the shaft, and the first externally threaded portion is engaged with a second internally threaded portion of the rotor. The screw seat has a screw seat surface. The adapter is screwed onto the shaft such that the adapter is pressed against the screw seat surface, and the rotor is screwed onto the adapter such that the rotor is pressed against the screw seat surface.

Abstract: The invention provides a compressor with a shut off valve disposed between the crank case and the suction cavity. The valve is moveable between an open and closed position in response to the pressure in the discharge cavity of the compressor. The valve is an on/off valve and is operable rapidly depressurize the interior of the crank case when the compressor transitions from a minimum stroke. The valve can define first and second fluid pathways. The first fluid pathway can be larger than the second fluid pathway and be selectively opened and closed. The second fluid pathway can be permanently open and act as a bleed between the crank case and the suction cavity.

Abstract: Small, high-performance centrifugal fan for cooling portable electronic devices. The centrifugal fan motor employs a cantilever-type impeller constituted by an impeller blade unit that includes a lower endwall portion at axial one end, having a wall surface for breaking the flow of air along the rotational axis, and an opening at the other axial end. The impeller is configured so that the radius r to the outer circumference of the impeller blade unit is smaller than the axial height h of the impeller. When an airflow that enters through the impeller opening is forced out towards outer periphery of the impeller blade unit, windage loss at the wall surface of the lower endwall portion of the impeller is reduced, which realizes high-efficiency cooling performance that complements motor performance.

Abstract: A compact turbomolecular vacuum pump (1) is driven by a cup-type motor (8). The cup-shaped rotor of the motor is preferably integrated into the pump rotor (14) and may define corresponding pumping stages, for instance Holweck stages, wherein the stators (11, 12) of said stages being preferably obtained by superimposing stator rings (11?, 12?).

Abstract: A fluid pump of the type in which a housing assembly has a first sub-housing having an electric motor therein which is in line with a second sub-housing having the impeller therein, with the motor having a rotor shaft which extends through a seal of the first sub-housing into the second sub-housing and with the impeller mounted on the rotor shaft so as to be rotatable by the motor, and the second sub-housing having inlet and outlet ports through which fluid, such as water, is able to be pumped through the second sub-housing.

Abstract: A variable-capacity vane pump comprising a body (1) comprising a cavity (2) in which a mobile ring (3) can move, inside which a hub (4) is located which is rotatable around a fixed axis (R) and equipped with vanes (5) which during rotation are supported against an inner face of the mobile ring (3), displacing structure for moving the mobile ring (3) as a function of a control pressure between a position centered on the axis of rotation of the hub (4) and an extreme eccentric position with respect to the axis of rotation of the hub (4). According to the invention, the displacing structure of the mobile ring (3) comprise a recess (10) provided in the wall of the cavity (2) of the body (1), and a projection (9) formed on the outer face of the mobile ring (3) and designed to slide in the recess (10) of the cavity (2) of the body (1) so as to form a control chamber in which the control pressure is applied.

Abstract: The invention relates to a regulatory device for a pump (2), whose delivery volume can be adjusted, said device comprising a control valve unit (3) for regulating a control pressure that operates in a control pressure chamber (21) of an actuator (4, 5). The control valve unit (3) comprises a threshold value control valve (22) and a delivery flow control valve (23). The threshold value control valve (22) is subjected to a pressure from a working line (7) on the delivery side and the delivery flow control valve (23) can be subjected to a consumer input pressure taken from a consumer supply line (8), at a comparison pressure connection (29). In addition, the delivery flow control valve (23) is subjected to a control pressure that counteracts the consumer input pressure, at a regulatory pressure measurement connection (27).

Abstract: A system and method is disclosed for controlling the input electrical current to an infusion pump stepper motor based on predetermined torque requirements. The system can include a motor controller and a non-volatile memory containing expected load torque values throughout a pump cycle. Responsive to the expected load torque values, the motor controller provides the stepper motor with a varying electrical current for overcoming load torque at each point in the pumping cycle. Additional factors can also be considered for varying the electrical current. These factors include, but are not limited to, temperature, pressure, and elapsed operating time.

Abstract: An air compressor comprises a tank portion for reserving a compressed air, a compressed air generating portion for generating the compressed air to be supplied to the tank portion, a motor for driving the compressed air generating portion, and a pressure switch mechanism having a pressure sensor in a part of the tank portion, and controlling the motor to be turned on or off in accordance with an output of the pressure sensor, characterized in that when the time change rate of the pressure within air tank is greater than a predetermined value, the motor is restarted without waiting until the pressure decreases to the switch on point at the time of pressure fall.

Abstract: A thick matter pump comprising a drive motor (50), a (reversible) hydraulic pump (6), and two hydraulic cylinders (5, 5?) coupled to conveyor cylinders (7, 7?) for conveying the thick matter. A regulator regulates the rotational speed N of the drive motor (50), and a regulating clement (18, 20) regulates the displacement volume V of the hydraulic pump (6). A control module (54) regulates the rotational speed N of the motor and the displacement volume V. For improved operational ease and reduction of fuel requirements, noise and waste gas emission, the control module (54) comprises a final control element (56) for regulating the conveyance capacity of the conveyor cylinders (7, 7?), and an electronic control unit (108) which reacts to the position of the final control element (56) and allocates a nominal value to the rotational speed regulator and to the displacement volume regulator (20), in a software-assisted manner.

Abstract: In a variable displacement swash plate type refrigerant compressor (10), a stopper (28) is provided for setting an initial angle of the inclination angle of a swash plate (23) when a drive shaft (19) is not driven. When the drive shaft (19) is driven by a driving power source of the compressor (10) under a non-operation condition of a refrigerant circuit, the stopper (28) is moved to permit the inclination angle of the swash plate (23) to be reduced from the initial angle in response to increase of compression work of the compressor (10) so as to suppress the increase of the compression work to save the driving power for the compressor (10).

Abstract: (57) The compressor comprises a compressor element (2) with a compression chamber (7), to which an inlet conduit (3) is connected, with an inlet valve (4) comprising a valve element (16) which is connected to a piston (13) which can be displaced in a housing (12). A control conduit (19) puts the pressure vessel (6) in the pressure conduit (5) into connection with the cylinder chamber (14) which is formed between the working side of the piston (13) and the housing (12). The valve element (16) is bypassed by a bypass (24) with a return valve (25). The cylinder chamber (14) is connected to the inlet conduit (3) by means of a connection conduit (20) which is provided with a controllable load valve (21) and, with open load valve (21) and, with open load valve (21), has a minimum flow section which is larger than that of the control conduit (19).