A metering pump is joined to the stepping motor, includes an eccentric mechanism converting a revolving motion of the stepping motor into a reciprocating motion of a plunger, and makes a constant liquid delivery by sucking and discharging an anesthetic agent through variations in the cubic volume of a cylinder caused by the reciprocating motion of the plunger. The control section: calculates a suction and discharge cycle T of the metering pump on the basis of a set anesthetic-gas concentration and a fresh-gas flow rate; sets a discharge period T2 of the cycle T to be longer than a suction period T1 of the cycle T; and controls the revolution speed of the stepping motor so that the travelling speed of the plunger is kept constant during the discharge period T2.

The dosing apparatus comprises a conveying device (5), which is driven by at least one conveying drive (4), for conveying fluid from the interior (3) of a container (2). The fluid by means of the conveying device (5) is conveyable from the container to a dispensing opening (6). The conveying device (5) comprises a cylinder (7) having at least one intake opening (11) and at least one outlet opening (12) on an inner cylinder wall (8), and a first piston (9) and a second piston (10). The first piston (9) and the second piston (10) are mounted within the cylinder (7) so as to be displaceable in the longitudinal direction. Furthermore, the first piston (9) and the second piston (10) between the end sides thereof and together with a portion of the inner cylinder wall (8) delimit a variable fluid volume (17).

The invention relates to an oil-free vacuum pump for evacuating gaseous media, comprising: an electric motor which drives a shaft; a pump housing having a pump chamber, as well as an inlet and an outlet; a prismatic displacement piston which is accommodated in the pump chamber such that it is bidirectionally active and can be moved on a reciprocal working section; and at least one pressure valve which releases an outflow of a gaseous medium out of the pump chamber through the outlet and blocks an inflow into the pump chamber. The displacement piston has a slot into which a drive force of the shaft is introduced via a crankpin by means of a rolling bearing.

A double acting alpha Stirling refrigerator includes a piston cylinder and a piston, the piston is provided in the piston cylinder. The piston is in a clearance fit with an inner wall of the piston cylinder. A closed cavity is formed inside the piston. A cross-shaped four-way pipe is provided in the cavity of the piston. A one-way air outlet valve and a one-way air inlet valve are further respectively provided on the four-way pipe in the cavity of the piston. An air outlet for connecting the cavity of the piston to the inner cavity of the piston cylinder is provided on the piston. A traction frame movable relative to the piston cylinder is provided outside the piston cylinder, and the movement of the piston is controlled by the movement of the traction frame.

A double acting alpha Stirling refrigerator includes a piston cylinder and a piston, the piston is provided in the piston cylinder. The piston is in a clearance fit with an inner wall of the piston cylinder. A closed cavity is formed inside the piston. A cross-shaped four-way pipe is provided in the cavity of the piston. A one-way air outlet valve and a one-way air inlet valve are further respectively provided on the four-way pipe in the cavity of the piston. An air outlet for connecting the cavity of the piston to the inner cavity of the piston cylinder is provided on the piston. A traction frame movable relative to the piston cylinder is provided outside the piston cylinder, and the movement of the piston is controlled by the movement of the traction frame.

A method of remanufacturing a fluid end block having a plurality of segments adapted to receive working fluid includes removing at least one damaged segment from the plurality of segments of the fluid end block. The method also includes providing at least one replacement segment at a location of the at least one damaged segment. The method further includes providing a seal between a first surface of the at least one replacement segment and a first surface of at least one adjacent segment of the plurality of segments. The method includes coupling the at least one replacement segment with the at least one adjacent segment to form a remanufactured fluid end block.

A method of remanufacturing a fluid end block having a plurality of segments adapted to receive working fluid includes removing at least one damaged segment from the plurality of segments of the fluid end block. The method also includes providing at least one replacement segment at a location of the at least one damaged segment. The method further includes providing a seal between a first surface of the at least one replacement segment and a first surface of at least one adjacent segment of the plurality of segments. The method includes coupling the at least one replacement segment with the at least one adjacent segment to form a remanufactured fluid end block.

Casing for a volumetric pump, said casing comprising a wall being in ceramic, characterized in that said wall comprises at least one opening means comprising a recess, a through-hole in the bottom of said recess and a nozzle being manufactured inside said recess, said nozzle being concentric with said through-hole and having a length inferior to the depth of the recess.

Casing for a volumetric pump, said casing comprising a wall being in ceramic, characterized in that said wall comprises at least one opening means comprising a recess, a through-hole in the bottom of said recess and a nozzle being manufactured inside said recess, said nozzle being concentric with said through-hole and having a length inferior to the depth of the recess.

A device is provided comprising a receiving chamber for receiving a patient's sample, a first reagent reservoir and a second reagent reservoir. The receiving chamber may be configured for receiving at least an end portion of a sample collecting element, with the patient's sample being collected by that sample collecting element. The first reagent reservoir may generally be configured to accommodate a liquid reagent which may include a lysing agent, i.e. the liquid may be a kind of a lysis buffer. Likewise, the second reagent reservoir may generally be configured to accommodate a dry reagent which may include magnetic particles. The device may further comprise at least one of the following two actuators, a first actuator for supplying a first reagent from the first reagent reservoir to the sample and a second actuator for supplying a second reagent from the second reagent reservoir to the resulting mixture.