Abstract: The present invention concerns a pump adjusting method and a membrane pump having a pumping chamber, a pressure and a suction connection, wherein the pressure and the suction connections are connected to the pumping chamber, a hydraulic chamber, wherein the pumping chamber and hydraulic chamber are separated from each other by a membrane, wherein a pulsating working fluid pressure can be applied to the hydraulic chamber which can be filled with a working fluid, wherein the membrane is moved between a first and second chamber positions of different volumes, wherein the chamber is connected to a working fluid reservoir, wherein the membrane comprises exchangeable spring elements exerting different forces on the membrane. The force which is exerted by the spring element on the membrane in the direction of the second position can be adjusted.

Abstract: The present invention concerns a pump adjusting method and a membrane pump having a pumping chamber, a pressure and a suction connection, wherein the pressure and the suction connections are connected to the pumping chamber, a hydraulic chamber, wherein the pumping chamber and hydraulic chamber are separated from each other by a membrane, wherein a pulsating working fluid pressure can be applied to the hydraulic chamber which can be filled with a working fluid, wherein the membrane is moved between a first and second chamber positions of different volumes, wherein the chamber is connected to a working fluid reservoir, wherein the membrane comprises exchangeable spring elements exerting different forces on the membrane. The force which is exerted by the spring element on the membrane in the direction of the second position can be adjusted.

Abstract: The present invention concerns a membrane pump having a hydraulic chamber (8) separated from a pumping chamber (9) by a membrane (1), wherein the pumping chamber (9) is respectively connected with a suction connection and a pressure connection and a pulsating working fluid pressure can be applied to the hydraulic chamber (8) which can be filled with a working fluid, wherein the hydraulic chamber (8) is connected to a working fluid reservoir (15) via a leakage compensation valve (6), wherein the leakage compensation valve (6) comprises a closing body which is held in a closed position with the aid of a pressure element and which can be moved to and fro between closed and opened valve gate positions, wherein the pressure element is designed such that when the pressure in the hydraulic chamber (8) is lower than a set pressure pL, the closing body (16) moves in the direction of the open position.

Abstract: A magnetic drive metering pump in which a movable thrust member is fixed to a diaphragm and is axially movable in a magnet shroud. The thrust member, on electrically actuating the magnet shroud, is drawn into the magnet shroud against the force of a recuperating spring, and after deactivating the magnet shroud, is returned to a starting position. The diaphragm cooperates alternately with an outlet and an inlet valve to produce a pump stroke in a pump metering head. The magnetic drive metering pump has a reference element associated with the thrust member and diaphragm, the position of which reference element is detected by a positional sensor. The positional sensor provides a signal which has a fixed relationship to the position of the reference element, and the motion of the thrust member is controlled by a control circuit such that it follows a predetermined nominal profile.

Abstract: A pressure retention valve including a housing having an inlet passage and an outlet passage that can be connected together and a separating diaphragm subdividing the housing into two portions, wherein, in operation of the valve, a first portion conveys fluid and a second portion is fluid-free. The valve further includes a valve seat defining an end of the inlet passage, arranged in the fluid-conveying portion of the housing, and has a first sealing surface, a shut-off body which is arranged movably in the fluid-conveying portion of the housing and has a second sealing surface, and a spring element having a spring force, which is arranged in the fluid-free portion of the pressure retention valve.

Abstract: The present invention concerns a multi-cylinder diaphragm machine having at least two hydraulically driven diaphragms includes: a drive unit for producing at least two pulsating hydraulic fluid flows for driving the diaphragms and a delivery unit for delivering a delivery medium and having at least two pump chambers, the volumes of which can be varied by the movement of a respective diaphragm, wherein each delivery chamber is connected by way of a pressure valve to a pressure line and by way of a suction valve to a suction line.

Abstract: The present invention concerns a drive mechanism for oscillating positive-displacement machines such as for example diaphragm pumps comprising an eccentric shaft and a plurality m of piston rods, wherein the piston rods are connected to the eccentric shaft in such a way that rotation of the eccentric shaft produces an oscillating linear movement of the piston rods. To provide a corresponding drive mechanism which avoids or at least reduces the described disadvantages it is proposed according to the invention that the eccentric shaft and the piston rod are connected together by way of a sliding unit guide.

Abstract: A separation element of a multi-layer structure for pressure compensation including: at least two mutually superposed flexible, fluid-tight material layers; at least one spacer element which is arranged between the material layers and holds them at a spacing relative to each other, wherein the at least one spacer element is such that the space between the flexible, fluid-tight material layers is at least partly adapted for fluid to flow therethrough, and at an edge region of the multi-layer structure the separation element has a sensor region (S) which is in a communication with remaining space between the flexible, fluid-tight material layers through which fluid can flow, wherein within the sensor region, the flexible, fluid-tight material layers are designed so that, by virtue of an inflow of fluid between them, an increase of pressure causes an increase in the spacing between the material layers relative to each other.

Abstract: A separation element of a multi-layer structure for pressure compensation including: at least two mutually superposed flexible, fluid-tight material layers; at least one spacer element which is arranged between the material layers and holds them at a spacing relative to each other, wherein the at least one spacer element is such that the space between the flexible, fluid-tight material layers is at least partly adapted for fluid to flow therethrough, and at an edge region of the multi-layer structure the separation element has a sensor region (S) which is in a communication with remaining space between the flexible, fluid-tight material layers through which fluid can flow, wherein within the sensor region, the flexible, fluid-tight material layers are designed so that, by virtue of an inflow of fluid between them, an increase of pressure causes an increase in the spacing between the material layers relative to each other.

Abstract: A metering pump with a rotary drive motor and an oscillating piston, wherein the rotary motion of a drive motor is transformed into an oscillatory motion of a connecting rod by means of a gear arrangement, so that a displacement means activated thereby executes an oscillating linear motion on continuous rotation of the drive motor, that results in transfer of a medium to be metered in a metering head (12) arranged in the longitudinal axis of the connecting rod (19) cooperating alternately with an outlet and inlet valve to produce a pump stroke (pressure stroke) and a priming stroke.

Abstract: A magnetic drive metering pump in which a movable thrust member fixed to a connecting rod is axially movable in a longitudinal axis in a magnet shroud anchored in a pump housing so that the thrust member with the connecting rod, on electrically driving (actuating) the magnetizing coil, is drawn into the magnet shroud against the force of a recuperating spring, reducing an air gap between the thrust member and an inner face of magnetic shroud, into a bore in the magnet shroud and after deactivating the magnet the thrust member is returned to the starting position by the recuperating spring so that the thrust member and an elastic displacement member actuated thereby on carries out an oscillating motion continued activation and deactivation of the magnetizing coil, which diaphragm cooperates alternately with an outlet and an inlet valve to produce a pump stroke (pressure stroke) and a priming stroke in a metering head arranged in the longitudinal axis.

Abstract: A fluoride-sensitive electrode having a tubular electrode shaft, a lanthanum fluoride crystal, which closes the end of the electrode shaft, an internal electrolyte sealed between the lanthanum fluoride crystal and a closure in the electrode shaft, and a contact wire which dips into the internal electrolyte, wherein the internal electrolyte has a pH of ?9.0 and a fluoride concentration of ?0.1 M. The invention also includes the method of using the electrode to determine fluoride ion concentration.

Abstract: The present invention concerns a sensor diaphragm comprising a plurality of diaphragm layers which are arranged in sandwich-like mutually superposed relationship and which include a conveyor or separating diaphragm (1), a first electrically conductive diaphragm layer (2) arranged therebeneath, an electrically insulating diaphragm layer (3) arranged therebeneath and a second electrically conductive diaphragm layer (4) arranged therebeneath, wherein the first and second conductive diaphragm layers (2, 4) are separated from each other and electrically insulated by the electrically insulating diaphragm layer (3) and the second electrically conductive diaphragm layer (4) has portions (7) which engage through openings (5) in the electrically insulating diaphragm layer (3) and through openings (6) in the first electrically conductive diaphragm layer (2) and the electrically insulating diaphragm layer (3) has portions (12) which engage through the openings (5) in the first conductive diaphragm layer.

Abstract: A safety diaphragm for a diaphragm pump, which makes it possible to detect a rupture of the diaphragm during operation or when at a standstill. The diaphragm has at least two diaphragm layers (1, 2) arranged lying one on top of the other The diaphragm has a clamping region (E) for fixing the diaphragm in a pump and has an adjacent operational region (A). The diaphragm layer (1, 2) are connected to each other so that they are sealed against penetration of liquid and/or gas between the diaphragm layers (1, 2). The diaphragm, in one section of the clamping region (E), has a sensor region (S) where the diaphragm layers (1, 2) are formed so that, in the case of an increase in pressure between the diaphragm layers (1, 2), the layers in sensor region (S) deform more easily than in the other sections of the diaphragm.

Abstract: The present invention concerns a sensor diaphragm comprising a plurality of diaphragm layers which are arranged in sandwich-like mutually superposed relationship and which include a conveyor or separating diaphragm (1), a first electrically conductive diaphragm layer (2) arranged therebeneath, an electrically insulating diaphragm layer (3) arranged therebeneath and a second electrically conductive diaphragm layer (4) arranged therebeneath, wherein the first and second conductive diaphragm layers (2, 4) are separated from each other and electrically insulated by the electrically insulating diaphragm layer (3) and the second electrically conductive diaphragm layer (4) has portions (7) which engage through openings (5) in the electrically insulating diaphragm layer (3) and through openings (6) in the first electrically conductive diaphragm layer (2) and the electrically insulating diaphragm layer (3) has portions (12) which engage through the openings (5) in the first conductive diaphragm layer.

Abstract: An electrode transport and storage system has an electrode with a sensor portion and an enclosure into which at least the sensor portion of the electrode projects and which together with the electrode encloses a storage chamber designed to contain a liquid for providing improved storage and transport for the electrode. The enclosure is formed as a rigid casing which is connected at the open end of the casing with the electrode. A sealing element is provided in-between the casing and the electrode. The storage chamber is filled with an electrolyte solution which immerses at least the sensor portion of the electrode while the sealing element retains the solution during transport and storage of the electrode. If desired, the electrode may be calibrated within the casing which is filled with a calibration solution.

Abstract: An amperometric dual-electrode sensor having an operating electrode inside a passivable metal electrode used as the counter electrode is provided by the invention. A method for measuring the concentration of a compound or ions in a sample is also provided by this invention. In particular, a method of measuring hydrogen peroxide in a sample is described.

Abstract: It is an of this invention to provide an electrochemical measurement cell capable of measuring the concentration of gaseous and charged or neutral compounds in a liquid. Accordingly, the present invention consists in one aspect in an electrochemical measurement cell having a working and a counter electrode surrounded by an electrolyte space filled with an electrolyte with a high viscosity, wherein the electrolyte space is at least partly delimited by a hydrophilic membrane. It has been surprisingly discovered by the present invention that charged or neutral compounds in a liquid, as well as gases, can be determined by means of an electrochemical measurement cell having a hydrophilic membrane and an electrolyte with a high viscosity.

Abstract: A stroke drive, particularly for displacement piston pumps, has a first eccentric (8) on which a second eccentric (9) is mounted. A push rod bearing (10) is connected to the second eccentric (9). The eccentrics (8, 9) are connected to each other by way of an intermediate drive (17) which conveys a synchronous rotation to the eccentrics. An adjusting device (16) serves to change the relative position of the eccentricities (e1, e2) of the eccentrics (8,9) relative to each other. In this manner the length of the stroke is steplessly adjustable from a maximal value to a minimal value.

Abstract: The present invention provides a vector plasmid capable of efficient tumor necrosis factor (TNF) production, a process capable of efficient TNF production in a host transformed with said plasmid and a composition containing the TNF produced by said process.The novel plasmid of the present invention is characterized by having inserted therein a DNA fragment that has a phage-derived promoter region upstream of a structural gene for TNF and in which a DNA fragment containing an E. coli gene-derived transcription termination coding base sequence (terminator) is joined immediately downstream of a base sequence coding for the termination of translation of said structural gene.