Mettler-toledo Ag

Mettler-toledo Gmbh

Thomas Köppel

Stephan Baltisberger

Hans-Rudolf Burkhard

Andreas Metzger

Dominique Genoud

Christophe Béguin

Daniel Reber

Jean-Christophe Emery

Ferdinand Schneider

Peter Schilling

Matthias Scheu

Hans-Rudolph Burkhard

Adrian Birrer

Erwin Kaderli

A parallel-guiding mechanism () has a movable parallel leg (), a stationary parallel leg (), a first parallel-guiding member () and a second parallel-guiding member (). The parallel legs and the parallel-guiding members are connected to each other by flexure pivots, in the form of narrow material connections. There is at least one adjustment zone (). An adjustment flexure fulcrum () is arranged between a flexure pivot () and a parallel leg. The adjustment zone is connected to the first lever end () of an adjustment lever (). The adjustment flexure fulcrum forms the lever fulcrum () of the adjustment lever, which has an elastic domain with a section modulus that is smaller than a section modulus of the adjustment flexure fulcrum.

Device and method for the adjustment of an eccentric load error in a parallel-guiding mechanism

A weighing cell based on the principle of electromagnetic force compensation and having an optoelectronic position sensor that includes a light source, a light receiver, and a shutter vane. The light receiver functions to generate a position sensor signal corresponding to a deflection of the shutter vane from a zero position which occurs as a result of placing a load onto a load receiver of the weighing cell. A controller functions to regulate compensation current in response to the position sensor signal in such a way that the shutter vane and the movable parts of the weighing cell connected to the shutter vane are returned to the zero position by the electromagnetic force between a coil and permanent magnet system of the weighing cell.

Weighing cell based on the principle of electromagnetic force compensation with optoelectronic position sensor

An exemplary method for the temperature correction of a force-measuring device such as a balance is disclosed. The method includes generating, by means of a force-measuring cell, a force measurement signal corresponding to the input force; generating an electrical temperature measurement signal by means of a temperature sensor that is arranged at a distance from the heat-generating components of the force-measuring device, processing the force measurement signal into a temperature-corrected output signal based on the temperature measurement signal and the force measurement signal; and transmitting the output signal to an indicator unit and/or to a further processing unit.

Method for the temperature-correction of a force-measuring device, and force-measuring device

A gravimetric measuring instrument that contains a weighing cell having a load-transmitting member. A load receiver can be coupled to the load-transmitting member through a releasable connection. A mechanical stop resides on the load-transmitting member, and a mechanical counter stop resides on the load receiver. By means of an eccentric bolt engaging the load receiver and the load-transmitting member, the mechanical stop can be pressed against the mechanical counter stop, whereby the stop can be clamped tight against the counter stop. With this arrangement, the load receiver can be rigidly but releasably secured to the load-transmitting member.

Gravimetric measuring instrument with releasable load receiver

A force-measuring device, particularly a balance, operates on the principle of electromagnetic force-compensation. An electric coilis arranged to be movable in a magnet system. The coil has at least two windings W, Wand a current supply device PB having at least two partial current sources PB, PB, the current sources each assigned to a corresponding winding. A device CU controls and/or regulates the current supplied to the windings by the partial current sources in such a way that, dependent on a force L acting on the force-measuring device, a current I, Iis sent through each of the windings. The sum of the at least two electromagnetic forces which are thereby generated forms the compensation force, while, at the same time, the power dissipated by the coil always takes on a given predetermined value Ptg.

Force-measuring device using electromagnetic force compensation with constant power dissipation

A parallel-guiding mechanism has a vertically movable parallel leg that carries a weighing pan. The movable parallel leg is connected by two essentially horizontal parallel guides to a stationary parallel leg installed in a balance, wherein elastic flexure pivots are formed at the ends of the parallel guides. Incisions that reduce the material strength of the parallel leg in at least one appropriate location define at least one adjustment domain, thus forming a deformation zone which is plastically deformed through application of an adjustment force. In this manner, a corner load error of the parallel-guiding mechanism is corrected.

Adjustable parallel-guiding mechanism, specifically for a gravimetric measuring instrument

In a parallel-guiding mechanism, a stationary parallel leg surrounds a movable parallel leg. The movable parallel leg is connected to the stationary parallel leg and guided in vertical movement by first and second parallel-guiding elements, fastened respectively to the upper and lower end portions. The movable parallel leg can be connected to a load receiver and to a force-measuring cell through a force-transmitting connection in order to transmit the weighing load. Intermediate to, and connecting, the respective end portions is a tilt-adjustment feature, by which the end portions are tilt-adjusted relative to each other about at least one tilt axis to correct a corner load error. The tilt-adjustment feature is provided by at least one of: a pair of bending zones, a spherical joint and a ring-shaped constriction.

Adjustable parallel-guiding mechanism for compact gravimetric measuring instruments

The calibration weight arrangement for an electronic balance () with a force-measuring cell () has a calibration weight () which can be coupled to the force-measuring cell (). A transfer mechanism and a drive source are used to move the calibration weight vertically, in order to establish, as well as to release, the force-transmitting contact between the calibration weight and the force-measuring cell. The transfer mechanism has at least one resetting element (), a lifting system () configured as a knee-joint linkage (), and a multi-stable positioning element (). Due to the feedback from the multi-stable positioning element, whose first stable state defines the calibrating position () and whose second stable state defines the rest position () of the transfer mechanism, the actuator () is energized only during the phases when the transfer mechanism is moving.

Calibration weight arrangement for an electronic balance

A weighing cell module with a force-transfer mechanism that includes a parallel-guiding linkage with a vertically movable parallelogram leg and a spatially fixed parallelogram leg, is equipped with a mounting area for a first weighing-pan support device with a single-point connection of a weighing pan, as well as with a mounting area for a second weighing-pan support device with a multiple-point connection, particularly a four-point connection, of a weighing pan, wherein the first and the second mounting area are each connected to the force-transfer mechanism. As a result, the weighing cell module can be used to manufacture different types of balances in a design family of balances, where each different type within the family is designed for a different maximum load.

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Oetwil am See, Switzerland

Thomas Köppel