Abstract: A measuring gas pump (1) has a pump chamber (3) closed by means of a working diaphragm (6). The strokes (double-headed arrow 26) are imparted to the working diaphragm (6) by way of a connecting rod or like lifting mechanism (9) from a crank mechanism (10). A heat source (16) is provided in the pump head (15). Provided between the connecting rod head (8) and the crank mechanism (10), there is a heat dissipation barrier (19 and/or 27) with respect to the measuring gas. By means of the measuring gas pump (1), the gas to be delivered thereby can be kept better to the temperature of the gas sampling condition and unwanted condensation of constituents of the gas to be analyzed and falsifications of the measurement result can be avoided or at least significantly reduced.

Abstract: A two-stage positive displacement pump (1) is used in particular to operate in conjunction with a turbomolecular pump (2) that can be placed ahead of it in series. The two-stage positive displacement pump (1) is configured as a hybrid pump (3) that has on the medium-entry side a reciprocating pump (5) with a comparatively large displacement area (6), whereby its piston-cylinder space (7) is sealed off with respect to the crank area (8) by means of a sealing membrane (9). Also as a part of this two-stage positive displacement pump (1) which forms the hybrid pump (3), there is placed in series behind the reciprocating pump (5) a diaphragm pump (10), whose displacement area (11) is noticeably smaller compared to that of the reciprocating pump (5).

Abstract: A diaphragm pump has a first fluid-operated valve which opens when the diaphragm performs a suction stroke and a second fluid-operated valve which opens when the diaphragm performs a compression stroke. The volumetric efficiency of the pump is enhanced by constructing at least one of its valves in such a way that the central portion of a resilient disc-shaped valving element, whose marginal portion bears against a seat when the valve is closed, abuts a supporting surface having a diameter selected in dependency on the diameter of the valving element, the thickness of the valving element and the Shore hardness of the material of the valving element in such a way that the selected frequency of the diaphragm in actual use of the pump induces a resonant frequency of the valving element. This also contributes to a reduction of noise and renders it possible to reduce wear upon the valving element and the adjacent parts of the respective valve.

Abstract: A diaphragm pump wherein the marginal portion of a contoured diaphragm is clamped between the cover and the case of the pump housing and the reinforced central portion of the diaphragm is reciprocated toward and away from the inner side of the cover by the connecting rod of a crank drive. The front side of the diaphragm and the inner side of the cover define a variable-volume pumping chamber which receives a fluid medium by way of an inlet and discharges the aspirated fluid medium by way of an outlet in the cover. The diaphragm has an intermediate portion which connects the central and marginal portions and is provided with an annular flexure zone including an annular protuberance at the rear side of the diaphragm.

Abstract: A peristaltic pump wherein an annular internal surface of the housing and a sleeve-like annular section of an elastically deformable diaphragm define an annular pumping chamber which communicates with the fluid-admitting inlet and with the fluid-discharging outlet of the housing. The diaphragm is provided with an extension which projects radially outwardly from the sleeve-like section and is partially anchored in a socket of the housing. A weakened portion of the extension between the anchored portion and the sleeve-like section is received in a compartment between the inlet and outlet of the housing and is provided with one or more empty or fluid-filled cavities, with one or more recesses, with one or more holes and/or other elasticity enhancing features to ensure that the resistance of the sleeve-like section to deformation will be uniform in each of its parts including that which is integral with the extension.

Abstract: A diaphragm pump wherein that side of the diaphragm which faces away from the pumping chamber is adjacent a noise intercepting insert. The insert is traversed by the connecting rod of the drive which oscillates the central portion of the diaphragm to draw a fluid into and to expel the drawn fluid from the pumping chamber. A deformable wall of the insert has a marginal portion which is attached to the housing, and this wall is separated from the diaphragm by an elastic distancing cushion of foam rubber or other sound absorbing material. The cushion can constitute a ring or it can consist of a set of projections which are affixed to or integral with the wall and face of the diaphragm. The cushion is compressed between the head of the connecting rod and the wall so that the latter is maintained in stressed condition.

Abstract: The invention relates to a table system in which at least two adjacent table elements can be releasably connected via their opposing table top edges with the aid of at least one mechanical connecting arrangement. Of the essentially two-part connecting arrangement a first main part contains a retaining lever which is built into the table top edge region of one table element and can be pivoted outwards, whilst the second main part of the connecting arrangement, built into the table top edge region of the adjacent table element, is constructed so as to receive the retaining lever form-lockingly and contains a securing element for the locking engagement between the first and second main parts. The assembly and disconnection of the individual table elements can be carried out quickly and reliably without additional aids.

Abstract: A diaphragm pump for fluids has a housing, a fluid displacement part including a displacement chamber and a pump diaphragm, and a flow control including a damping chamber arranged to absorb pressure impacts a fluid in aspiration region and having an adjustable fluid admission volume so as to change a fluid supply to the pump diaphragm.

Abstract: A pump comprises a housing member bounding an elongated cylinder bore, a piston member received in the cylinder bore for reciprocation substantially longitudinally thereof, a drive for the piston member, and a sealing arrangement between the piston member and the housing member. The sealing arrangement includes at least one sealing element having a radial supporting section and at least one lip section sealingly contacting the housing member. The wall thickness of the supporting section exceeds that of the lip section. The sealing arrangement may further include another lip section pointing in the opposite direction counter to that of the one lip section, either provided integrally on the same sealing element or separately on a discrete second sealing element assembled with the initially mentioned sealing element to form the sealing arrangement.

Abstract: The PC-boards are contained in sealed enclosures, and serially effective heat pipe systems conduct thermal energy from the respective sources of development (e.g., power transmitters) to the top and from there to a heat pump system. Stacking such units and operating the heat transfer partially in parallel is disclosed.

Abstract: A membrane pump comprising a housing having an inner cylindrical surface, an annular member in the housing and having an outer surface defining with the inner surface of the housing a working space. A hollow rolling piston is arranged in the interior of said annular membrane. An eccentric drive including an arm fixed at one end to a drive shaft carries at its other end a roller engaging the inner surface of the rolling piston for rotating the latter about its axis while pressing the outer surface thereof against the inner surface of the membrane, whereby the outer surface of the membrane is pressed at a revolving sealing region against the inner surface of the housing.

Abstract: A diaphragm pump, especially a vacuum pump for gases, includes at least one diaphragm extending transversely through the pump housing and defining therewith a pumping chamber. Drive means connected to the diaphragm moves the latter between a suction stroke at which gas is sucked into the pumping chamber through an inlet and a compression stroke in which the gas is pushed out of the pumping chambers through an outlet. The diaphragm is clamped at its outer periphery to the pump housing and at its central portion to the drive means moving the diaphragm between the suction and compression strokes.

Abstract: A diaphragm pump, especially a vacuum pump, in which a diaphragm of elastomeric material is clamped at its outer peripheral portion against a peripheral portion of a rigid wall which has, radially inwardly of the clamped portion, a concavely curved spherical surface forming with the diaphragm a pumping chamber with which inlet and outlet ports, each provided with a one-way valve, communicate. A central substantially rigid portion of the diaphragm is moved between a suction stroke increasing the volume of the pumping chamber, and a compression stroke. The wall surface and the diaphragm are constructed and arranged relative to each other that the volume of the pumping chamber is reduced substantially to zero at the end of the compression stroke and so as to permit easy sliding movement of portions of the diaphragm and the surface of the wall as the diaphragm approaches the end of the compression stroke.