Abstract: Incompletely condensed aldehyde resin having a large surface area and formed in the presence of large quantities of water under mild conditions is used for removing waste products, such as urea, from the blood in hemodialysis or for removing such impurities from swimming pools or aquariums.

Abstract: A weighing machine employing electromagnetic forces having a weighing pan which is mounted at the top portion thereof. An electromagnetic coil is employed in an air gap of a stationary permanent magnet system for generating a compensating force. The coil has a rectangular shape while the permanent magnet system consists of rectangular plates of magnetically active material with the vertical direction of magnetism being above or below the longer sides of the coil. A horizontal compensating force results.

Abstract: A circuit for electronic weighing scales, for example, for shifting or switching the circuit between two states and at the same time for de-chattering mechanical contacts, wherein the circuit includes two inverted gates with crossed feedback constituting a flip-flop. A first resistor is connected in the feedback from the output of the second gate to the input of the first gate, and a condenser has one electrode connected to constant potential and another electrode connected to the output of the first gate. A second resistor of high impedance is connected between the condenser and the output of the first gate, and an operating contact is arranged between the second electrode of the condenser and the input of the first gate.

Abstract: A balance is provided with a digital readout, a display device and transfer device for transferring measured values to the display device at a selected frequency. The frequency can be varied. An accessory circuit is provided for modifying at least the last digit appearing on the display device in response to an arrest criterion or a condition of the balance, such as an open measuring chamber or position of a draft shield. The criterion can be developed from comparing successive measured values.

Abstract: An electronic weighing apparatus having a load pan, a load receiver forming part of a parallel construction and supporting the pan, weight compensating means, and at least one force-transmitting lever having a short arm and a longer arm, connected at its short arm to take up the force transmitted by the load pan, and connected at its longer arm with the weight compensating means, wherein a built-in calibrating device includes a calibrating lever having an arm connected via a coupling element in force transmitting relation with the load receiver such that the force-transmitting connection can be selectively established or broken.

Abstract: An electromagnetically compensating measuring apparatus, as in force measuring or weighing devices, wherein a compensation coil is wound upon a coil form movable in the air gap of a stationary permanent magnet system having a pole plate, a capacitive position sensor is connected to detect the position of the compensation coil, and an automatic volume control amplifier is series-connected to the position sensor so as to follow it, with the output of the amplifier connected to feed the compensation coil to tend to hold it in a predetermined zero position, and wherein the coil form and the pole plate each form an electrode of the position sensor.

Abstract: A multipart filter case assembly for holding at least one cartridge-shaped filter element for sterile filtration of fluids comprises means to detect and detour leaking fluids, and includes a bell-shaped top part; an intermediate plate, which closes off the top part; an end cap; a filter-chamber, which closes off the intermediate plate; at least two ring-shaped packings arranged at a longitudinal distance on the end cap against the top part; a filtrate chamber, which closes off the intermediate plate; and at least one leakage control channel, which connects the space between the two ring packings with the outside of the case.

Abstract: A weighing machine with an explosion proof case enclosing the weighing system and having an electric or electronic indicator and a weighing scale for holding the material to be weighed, the case offering a specific resistance to a specific explosion pressure inside the case, whereby the scale may be safely used in an explosive environment without danger of causing an explosion exteriorly of the case due to electric arcing or the like caused by the scale electrical system inside the case.

Abstract: A multipart filter case for holding at least one cartridge-shaped filter element, particularly for the sterile filtration of fluids, has a bell-shaped case with a top part into which the filter inlet side protrudes. The filter outlet side is held downstream in an intermediate plate and ends in a filtrate space below the intermediate plate. The filtrate space is defined in part by a dish-shaped base plate parallel to the intermediate plate, and has a filtrate outlet therein. The inlet for the medium to be filtered extends through the base plate and intermediate plate into the top part of the case, and comprises a tubular part integral with the intermediate plate and which detachably penetrates the base plate.

Abstract: A device for mass transfer between fluids through a diaphragm unit comprising a pair of diaphragms with a diaphragm support therebetween, in which the diaphragm unit is a pleated package supported in a case, with the pleats and support defining a plurality of separate flow paths, and the diaphragm unit is shaped in a direction transverse to the longitudinal axis of the pleats with a zig zag or sine-wave shape, so that a compound zig zag or sine-wave shape results for the unit.

Abstract: A scale of the electromagnetic force compensation principle, having a stationary permanent magnet system with an air gap and at least one coil positioned in the air gap, the coil being acted upon via a position sensor and a variable-gain amplifier by a compensation direct current dependent on the load of the scale, wherein the compensation direct current flows through a measuring resistor from both ends of which a signal dependent on the load of the scale is tapped off and fed to an analog/digital converter, and further electric circuits are connected therewith which permit an alternating current to flow, in addition to the compensation direct current, through the coil and the measuring resistor and including a regulating or adjusting device which modifies the amplitude of the additional alternating current in such a manner that the joulean heat generated in the coil and in the measuring resistor by the compensation direct current and by the additional alternating current is at least approximately load-indepe

Abstract: An electromagnetically compensated precision scale has a load support guided for parallel movement by a guide assembly comprising upper and lower guides defining a triangular shape in plan connected to a housing and to the load support by flexible couplings, and wherein the guides are one-piece and define a vertical joint at the triangle apex, thereby reducing inaccurate readings caused by thermal effects.

Abstract: A weighing machine with a function key device and an electronic indicator, wherein the function key device comprises an electrically conductive contact sensor and a micro key device with a movable element arranged behind the contact surface and operatively connected therewith, so that manual pressure on the contact surface can operate the device either by electrical contact with the contact surface or by movement of the micro key device.

Abstract: An electromagnetic force-compensating weigher with a load supporting device resiliently supported by resilient joints and movable between stops, wherein electric circuitry is connected to produce a slowly decaying mechanical oscillation upon the load supporting device, to thereby reduce the spring hysteresis of the resilient joints.

Abstract: An electromagnetic force-compensating weighing appliance has at least two levers engaged at one of their ends in supporting relationship to a load scale, and each connected at their other ends to a respective compensating coil, the compensating coils being symmetrically disposed in the air gap of a single magnet unit, and the levers being pivotally supported between their ends on fixed supports.

Abstract: Apparatus for overload protection of precision or analysis scales having a parallel-guided load support with limit stops to limit the range of movement thereof, comprises an auxiliary parallel guide connection between the weighing pan and load support, and resiliently yieldable means connected between the weighing pan and load support to yield under excessive or improperly placed loads and thus protect the scale mechanism. The resiliently yieldable means may comprise the auxiliary parallel guide or may comprise a separate means.

Abstract: A flat weighbridge has a load platform supported by either two one-armed or two two-armed levers arranged at least partly beneath the load platform, wherein one lever is bifurcated to define two spread apart sides and each of the sides bears a supporting device for the load platform, while the other lever bears only one supporting device for the load platform.

Abstract: An asymmetrical ultrafiltration membrane based on cellulose triacetate, optionally substituted by up to 30% cellulose diacetate, is made wettable without tendency to embrittlement or shrinkage by adding hydrophobic synthetic silicic acid to the casting solution.

Abstract: An overload protection device for a top pan precision scale having a weighing pan support and a support plate carried by a load support mounted for limited movement and connected to an indicator, includes a spring engaged between the weighing pan support and the support plate whereby the weighing pan support is resiliently coupled to the load support, and a plurality of overlapping elements carried by the weighing pan support and extending beyond the outer peripheral edge of the support plate in close proximity thereto so that the weighing pan support and support plate are held in assembled relationship against the bias of the spring by the overlapping elements at the outer peripheral edge of the support plate, whereby upon eccentric loading of the scale, the pivot point of the weighing pan support is extended to the side of the weighing pan support opposite the load, and the lever translation thus effected results in a lower load on the load support than the highest available load.

Abstract: A balance having an electromagnetically compensated loading system and an electromagnetically compensated reference system includes respective signal pathways provided for feeding signals which arise in or are derived from the two systems. These signals are to be compared for measurement. The signals from the two pathways are processed coincidentally with one another for digitization, beginning simultaneously and ending simultaneously.