Mettler-toledo Ag

Mettler-toledo Gmbh

Daniel Reber

Christoph Lang

Hans-Rudolf Burkhard

Marc Nussbaumer

Jean-Christophe Emery

Jean-Maurice Tellenbach

Stephan Baltisberger

Thomas Köppel

Urs Loher

Hansruedi Künzi

Cyrill Bucher

Luzi Hess

Aaron Skidmore

Stefan Bühler

Hansruedi Kuenzi

Hans-Peter Von Arb

Stefan Buehler

Philip R Ouellette

Adrian Birrer

Hans De Waal

Martin Rickli

A monoblock sensor body of a load cell based on an electromagnetic force compensation mechanism has a Roberval mechanism. Mounting portions mount the fixed column to a housing side of a weighing module, and mount a load receiving member to the movable column. At least one of the mounting portions has at least one mounting hole that extends predominantly orthogonal to the load direction. One of the flexure point sections is closest to the mounting hole. A cavity associated with at least one of the mounting portions reduces an available solid angle for straight propagation paths that run from the inner thread to one or more of: the closest flexure point section, the coupling and the closest fulcrum. A material boundary of the body closes the cavity over at least a bridging width versus the height-side end of the body corresponding to the closest flexure point section.

Monoblock sensor body and method of its manufacturing

A verification of a pipette results in a release or a warning message. A liquid measuring container () receives the pipette liquid volume (V) to be verified. A loading cell () is connected to the liquid measuring container in a force-transmitting manner. The loading cell outputs a measurement signal (ms) corresponding to the weight force (F) acting thereon. A processing unit () detects and processes the measurement signal (ms), determines a first weight force (G) at time point (t) and determines a second weight force (G) at time point (t). The pipette liquid volume is calculated and the calculated value is assigned to a pipette volume class (K) having a defined class nominal value (VK). The processing unit tests whether or not an absolute value of the volume difference (&#x394;V) is within a predetermined tolerance value (T) for the assigned pipette volume class. The processing unit outputs the test result.

Method for the verification of pipettes

An electromagnetic force-compensation direct measuring system () has a load receiver (), which is connected to a force-compensation device () via a power-transmission linkage. The system has a multipart parallel guide mechanism, which has at least two parallel-guiding members () spaced apart by the power-transmission linkage. The force-compensation device has at least one permanent magnet () and a coil () electrically connected to a controllable electrical circuit. At least one parallel-guiding member is electrically integrated in the controllable electrical circuit. The power-transmission linkage is designed as a single-part coil body () such that the coil is arranged on the coil body between the parallel-guiding members and is electrically connected to the controllable electrical circuit.

Compact direct measuring system

A balance () has a weighing pan () that is held in a predetermined free-floating and constant position relative to translatory and rotary displacements in the six degrees of freedom during use. At least six position sensors are used to measure the position of the weighing pan in all three dimensions. A weighing mechanism having at least six electromagnetic mechanisms () generate compensation forces (F-F) that act on the weighing pan by sending currents through a force coil () associated with an associated permanent magnet. The weight of an object on the weighing pan is determined from the amounts of current flowing in the respective force coils to maintain the weighing pan in position.

Balance with free-floating weighing pan

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 method, an arrangement and a program process a measurement signal generated in a measurement transducer of an electronic force-measuring device, particularly a balance. The generated measurement signal corresponds to the force acting on the transducer. The measurement signal is entered directly or by way of a pre-processing stage into a display function which assigns corresponding output values to the values of the measurement signal. The output values are subsequently presented in a display or passed on for further processing. The input range of the display function contains a capture range, so that the values of the measurement signal that lie within the capture range are assigned a common output value by the display function, and the position of the capture range within the input range is controlled dependent on the generated measurement signal.

Signal-processing method for use in a force-measuring device and force-measuring device

A device and method for effectuating the temperature compensation testing of digital load cells. The device uses conductive heat transfer to establish and maintain the temperature of the load cell(s) during testing. The device may include a vessel into which one or more load cells to be tested are placed. Temperature control of the load cells may be accomplished by circulating a temperature controlled fluid through the vessel. The vessel containing the one or more load cells may then be placed in a load application device that applies a load(s) to the one or more load cells during testing. Readings from the one or more load cells are used to establish a temperature compensation factor for each load cell tested. In other embodiments, temperature control of the load cells may be accomplished by placing the load cells in contact with a solid heat transfer element(s).

Device and method for temperature compensation testing of digital load cells

A method serves to optimize the behavior of an electronic force-measuring device, in particular a balance that comprises a measuring transducer through which a measuring signal is formed which is representative of a load applied to the force-measuring device, which measuring signal is delivered to a signal-processing unit that is supported by at least one processor and at least one memory storage unit and serves to process digital signals. First characteristic traits for the condition of the force-measuring device are determined, the first characteristic traits being the result of internal and/or external factors affecting the force-measuring device, and/or second characteristic traits for the force-measuring device are determined from the analysis of at least one signal profile of the measuring signal, whereupon the condition of the force-measuring device is determined on the basis of the first and/or second characteristic traits, and the further processing of the measuring signal and/or the operation of the force-measuring device is controlled accordingly. Based on the condition of the force-measuring device that was determined, the processing or evaluation of the signal as well as the use of optimizing measures that serve to determine, e.g., optimized correction parameters such as drift parameters or filter parameters can be advantageously controlled.

Method of optimizing the behavior of a force-measuring device, and force-measuring device

A method serves to process output signal of a measuring transducer in a force-measuring device, in particular in a balance, wherein the measuring transducer produces a measuring signal representative of a load acting on the device and the measuring signal is filtered in a variable analog filter and/or, after processing in an analog/digital converter, the measuring signal is filtered in a variable digital filter, in order to remove unwanted signal components that are caused by disturbances affecting the force-measuring device, in particular by changes in the weighing load. The measuring signal is monitored in regard to the occurrence of a change in the weighing load and after a load change has been detected, at least one filter parameter of the filter is reset and then varied as a function of time in accordance with a prescribed time profile f(t), so that the filter is opened after a load change has been detected and then closed again to the point where a predefined filter characteristic has been attained which is determined by the end value of the at least one filter parameter. By using this method, it is possible with simple measures to realize noticeably shortened transient settling times of the force-measuring device after a load change has occurred.

Method of processing the output signal of a measuring transducer, and force-measuring device

The force-measuring device includes a measuring unit and a reference unit, the latter serving to deliver a reference quantity, a reference current (I) or a reference voltage (U), through which the force (F) of a measurement object which is to be determined can be measured by the measuring unit. The reference unit is a force-measuring device which is loaded with a reference mass and which in accordance with the principle of electromagnetic force compensation generates a reference current (I) that can be regulated through a measuring- and regulating device in such that in a first reference coil which is held by a reference lever, the reference current (I) generates a magnetic field which cooperates with the magnetic field of a reference magnet. Through this cooperation a magnetic force is brought to bear on the reference lever. As a result, the force (F) of the reference mass which is likewise acting on the reference lever can be compensated by said magnetic force.

Force-measuring device and reference unit

The output signal from a measuring transducer in a force-measuring device is processed by filtering a measuring signal (ms), representing a load that is acting on the transducer, to suppress interfering signal portions caused by extraneous influences including mechanical disturbances, or changes of the load. The measuring signal (ms) passes through a first delay element (A) to a measurement value unit () which holds the value of the currently received measuring signal (ms), a mean value based on the most recent values of the measuring signal, or an expected value (ms) based on the most recent values of the measuring signal. The measuring signal (ms) is monitored for signal disturbances using a first detector module (). After detection, a switching means () is actuated and the output signal (ms) of the measurement value unit is processed further, if applicable, and sent to the output end of the device, instead of the currently received measuring signal (ms).

Method for processing the output signal of a measurement transducer, and force-measuring device

A force-measuring device () with at least one housing () has an interior space and at least one force-measuring cell () installed therein. At least one parameter characterizing an existing high-frequency electromagnetic field is determined by a sensor () arranged in the interior space or a sensor arranged outside of the housing, the sensor being adapted for detecting high-frequency electromagnetic fields. After an electromagnetic field is detected and compared to a threshold value, a response action of the force-measuring device is triggered if the detected parameter value exceeds the threshold value.

Sensing RF and EM interference of a force-measuring device and adjusting operation accordingly

A method is disclosed for correcting transfer errors of an analog amplifier that occur following a jump in the amplifier input signal caused by switching. A measuring device includes at least one sensor as well as a signal-processing unit connected to the sensor and analog amplifier. The signal-processing unit includes at least one modulator and/or a multiplexer, an analog amplifier and at least one processing stage following the analog amplifier in the circuit chain. The processing stage, dependent on the point in time when the switching jump occurs, is separated from the latter during a predetermined timeout phase duration by means of a switch that is arranged between the analog amplifier and the processing stage and is controlled by a timeout controller, and/or dependent on the point in time when the switching jump occurs, said processing stage is blocked by a timeout controller during a predetermined timeout phase duration.

Method of correcting the output signal of an analog amplifier, amplifier module and measuring device

A method serves to correct drift phenomena, in particular creep effects, occurring in an electronic balance that has a measuring transducer through which a measuring signal is formed which is representative of a load applied to the force-measuring device. The measuring signal is delivered by way of an analog/digital converter to a signal-processing unit that is supported by at least one processor, said signal-processing unit being capable of compensating drift deviations, for which purpose the signal-processing unit, via the processor, accesses drift parameters that are stored in a memory unit and serve as basis for calculating a time-dependent correction value by which the drift error of the measuring signal (ms) is corrected. At time intervals that are either controlled automatically or chosen by the user, new optimized values for the drift parameters are determined automatically by the processor and the signal-processing unit under the control of an optimization program that is stored in the memory unit, and the new optimized values are filed in the memory unit.

Method for the adaptive correction of drift phenomena in a force-measuring device, and force-measuring device

A force-measuring apparatus, particularly a weighing cell, has a stationary part , a load receiver , a measuring transducer , and a lever for transmitting a force from the load receiver to the measuring transducer. An improved arrangement is proposed for changing the lever ratio by providing at least two different locations so that the fulcrum pivot flexures can be attached either at positions and or, alternatively, at positions and of the lever/stationary part.

Growing community of inventors

Madetswil, Switzerland

Daniel Reber