Repositioning In Response To Deflection Under Load Patents (Class 177/212)
  • Patent number: 6693245
    Abstract: A Roberval's mechanism and a lever are configured separately. To the Roberval's mechanism, a lever housing section is formed for inserting the lever in the longitudinal direction and enabling the lever to be located between a pair of the upper and the lower Roberval's sections. To the other end of the lever, a section extending outwards beyond the lever housing section is equipped. A balance driving portion are mounted to the section equipped to the other end of the lever and extending outwards. The lever block is situated to extend through a hollowed out section of the fixed end of the Roberval load block. During manufacture, the lever is formed from a separate piece that has temporary bridges formed to maintain the fixed section and the mobile sections relatively immobile so that the spring sections are protected during assembly. After the lever is connected to the Roberval mechanism, the bridges are cut.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: February 17, 2004
    Assignee: Anritsu Corporation
    Inventors: Hiroaki Watabiki, Norikazu Murata, Akio Sakai
  • Patent number: 6657138
    Abstract: An electronic weighing sensor (10) having a digital signal processing unit (19), which includes at least one filter (12) with low-pass characteristic. By means of the filter (12), the direct-current component (m) is determined from the output signal of the weighing sensor and the weighing result is derived therefrom. A signal, which is dependent on the amplitude of the vibrations, is determined by the digital signal processing unit (19) and electronic components (18) change the direct-current component (m) as a function of the magnitude of the vibration-dependent signal. This significantly improves the performance of the weighing sensor (10) with respect to shocks and vibrations in the installation site of the weighing sensor (10).
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: December 2, 2003
    Assignee: Sartorius AG
    Inventors: Alfred Klauer, Joerg Peter Martens
  • Patent number: 6563060
    Abstract: By using a second Roberval mechanism having beams orthogonal to beams of a first Roberval mechanism for supporting a weighing dish by a movable pillar and integrating a movable pillar of the second Roberval mechanism with a movable pillar of the first Roberval mechanism, longitudinal and crosswise one-sided loads are shouldered by first and second Roberval mechanisms and. Furthermore, by forming flexible portions flexible for one-sided loads (right and left one-sided loads) about the axis of the first Roberval mechanism on the first Roberval mechanism, torsions due to one-sided loads in the crosswise directions are prevented and influences of the torsions can be reduced. Moreover, by forming flexible portions flexible for a longitudinal one-sided load on the second Roberval mechanism, a torsion due to the longitudinal one-sided load is prevented and influences of the torsion can be reduced.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: May 13, 2003
    Assignee: Shimadzu Corporation
    Inventor: Akira Komoto
  • Publication number: 20030042052
    Abstract: Protruding part of a mechanism body is connected to a base frame by screws, and other protruding part is connected to an auxiliary connecting metal fittings by the screws. A machining necessary for connecting is conducted on the protruding portions, the widths of which are wide. Therefore, a sufficiently long distance can be obtained by the protruding portions. As a result, the Roberval's parts 4, 5 are not affected by stress strain, which is caused in the process of connecting, even if a size of an electronic balance in a longitudinal direction is not extended. Accordingly, it is possible to realize the compact electronic balance of high performance in which an accurate measurement can be made even if a load is given to a balance pan being biased.
    Type: Application
    Filed: July 29, 2002
    Publication date: March 6, 2003
    Applicant: SHIMADZU CORPORATION
    Inventor: Atushi Iiduka
  • Patent number: 6472618
    Abstract: A weighing scale includes an integral block member having a load receiving portion for receiving a load of a scaled object; a fixing portion for fixing the integral block; and a Roberval portion having recessed portions between the load receiving portion and the fixing portion. The scale also includes a load transmitting beam; a member for transmitting displacement of the load transmitting beam and the load receiving portion to the load transmitting beam and for becoming a force point of the load transmitting beam; a fulcrum member of the load transmitting beam; and a fulcrum member attachment portion being formed on the integral block so that the fulcrum of the of the load transmitting beam is positioned in a space thereby constituting the weighing scale. The member for transmitting displacement of the load transmitting beam and fulcrum member of the load transmitting beam are formed separately from the integral block member. An integral block member may include a working guide recess.
    Type: Grant
    Filed: March 27, 2000
    Date of Patent: October 29, 2002
    Assignee: A&D Co., Ltd.
    Inventors: Naoto Izumo, Kyouhei Ohyama, Eiichi Yoshida
  • Patent number: 6365847
    Abstract: In a weight sensor operating according to the principle of electromagnetic force compensation, the essential parts are fabricated from a single block of material. The weight sensor has a load receiver (10), which is connected through an upper guide (12) and a lower (11) guide to the housing-integral base body (1) of the material block. The weight sensor also has several force-reduction translating levers (21,22; 24, 25,25′; 27,27′,28) and coupling elements (18,18′, 23, 26,26′) between the translating levers (21, 22; 24 ,25,25′; 27,27′,28). The housing-integral base body (1) projects in the direction of the load receiver (10), extends into the space between the two guides (11, 12) and forms a support point for the first translating lever (21, 22). The weight sensor is equipped with a coil (34), which is fastened at the longer lever arm (28) of the last translating lever (27,27′,28,29,29′) and is situated in the magnetic field of a permanent magnet.
    Type: Grant
    Filed: May 22, 2000
    Date of Patent: April 2, 2002
    Assignee: Sartorius AG
    Inventors: Michael Müller, Ulrich Bajohr, Rudolf Müller, Werner Schulze, Detlef Erben, Herbert Engelhardt
  • Publication number: 20010052431
    Abstract: An electronic weighing sensor (10) having a digital signal processing unit (19), which includes at least one filter (12) with low-pass characteristic. By means of the filter (12), the direct-current component (m) is determined from the output signal of the weighing sensor and the weighing result is derived therefrom. A signal, which is dependent on the amplitude of the vibrations, is determined by the digital signal processing unit (19) and electronic components (18) change the direct-current component (m) as a function of the magnitude of the vibration-dependent signal. This significantly improves the performance of the weighing sensor (10) with respect to shocks and vibrations in the installation site of the weighing sensor (10).
    Type: Application
    Filed: May 21, 2001
    Publication date: December 20, 2001
    Applicant: SARTORIUS AG
    Inventors: Alfred Klauer, Joerg Peter Martens
  • Patent number: 6232567
    Abstract: To counteract the adverse effects associated with mounting a parallel-guiding device on a supporting part of a balance, the attachment area (30) is located on a portion (14) of the stationary leg (12) of the parallel-guiding device. Portion 14 projects into the space between the two guide links 3 and 6 by which the load-receiving movable leg (11) of the parallelogram is guided in parallel motion relative to the stationary leg (12).
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: May 15, 2001
    Assignee: Mettler-Toledo GmbH
    Inventors: Bruno Bonino, Hans-Rudolf Burkhard, Ferdinand Schneider
  • Patent number: 6057516
    Abstract: A thermogravimetric instrument for measuring variations in the weight of a sample caused by temperature variations of the sample. The instrument is equipped with a stopper mechanism for protecting the pivot to facilitate replacing a balance beam. A thermogravimetric instrument comprising: a balance beam 1 placed horizontally; a sample holder 9 located at one end of said balance beam; a torsion wire 3 mounted as a pivot and connected with the other end; a junction portion permitting a sample container side of the balance beam to be detached; and one or more stopper mechanisms using fixed stoppers 4 and metal plates 5. The stopper mechanisms limit relative movement between a supported portion of the torsion wire and the balance beam to within a prescribed amount to limit force applied to the torsion wire during detachment of the balance beam.
    Type: Grant
    Filed: July 18, 1997
    Date of Patent: May 2, 2000
    Assignee: Seiko Instruments, Inc.
    Inventors: Toshihiko Nakamura, Haruo Takeda
  • Patent number: 5886301
    Abstract: A device and method are described for measuring the weight of objects using a pneumatically sealed bellows which contains a pair of spaced apart capacitor plates. In accordance with the invention, the pneumatic pressure within the bellows is varied to maintain constant dimensions for the bellows and a constant distance between the electric capacitor plates. This pressure is therefore a function of the weight placed upon the bellows which exerts a pressure tending to force the walls of the bellows and the capacitor plates closer together thereby changing the electric capacitance between the capacitor plates. By adjusting the pneumatic pressure to maintain a constant electric capacitance and constant dimensions for the bellows, a convenient parameter is obtained from which the weight of objects placed on the bellows can be measured. The invention has particular application in the meteorological sciences.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: March 23, 1999
    Assignee: Vitel, Inc.
    Inventor: Duane Preble
  • Patent number: 5850057
    Abstract: A weighing apparatus capable of actively weighing a load in a rapid and accurate manner is presented. The weighing device includes an electromechanical linear actuator coupled to a load cell, wherein the output of the load cell is received by a feedback controller that generates an input signal received by the electromechanical linear actuator. A processor receives both the output signal and a measured value of the input signal and derives therefrom a weight for the load coupled to the weighing device. By employing the load cell output for feedback, the need for a position sensor is eliminated. The response time of the apparatus is enhanced by the electromechanical linear actuator which functions to quickly bring the load being weighed to a mechanical equilibrium position. Weight values may also be obtained by forcing one of the input or output signals to zero and then measuring the other of the signals.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: December 15, 1998
    Assignee: The University of Akron
    Inventor: Robert J. Veillette
  • Patent number: 5652411
    Abstract: A top loading load cell mass comparator having a load cell and a cantilevered beam connected between the load cell and a weight supporting platform which is self-centering to compensate for off-center loading when moving or replacing weights on the platform. A preload compressive force is applied to the load cell to minimize hysterisis and creep error in the load cell during weight exchanges on the weight supporting platform.
    Type: Grant
    Filed: April 18, 1995
    Date of Patent: July 29, 1997
    Assignee: Frazier Precision Instrument Company, Inc.
    Inventors: Thomas F. Scrivener, Zhong Qian Mo
  • Patent number: 5613419
    Abstract: A load balancing arm is shown and described as having improved control including a programmable control element and electronic air regulation to provide precise and controllable lifting force on a load. The disclosed load balancing arm responds to slight operator applied force to aid in movement of the load in overcoming system hysteresis, friction and load inertia without requiring the operator to apply a sufficiently large magnitude force to overcome such counteracting forces in the system. The disclosed load balancing arm further includes automatic load weight detection sensors for accommodating variation in load weights while applying a lifting force to the load which substantially equals the weight of the load. This allows the operator to move the load freely throughout a work space.
    Type: Grant
    Filed: October 10, 1995
    Date of Patent: March 25, 1997
    Assignee: Integrated Systems, Inc.
    Inventors: Cary M. Pierson, Stephen L. Heston
  • Patent number: 5493078
    Abstract: An electronic balance provided with a correcting circuit for canceling a thermal drift in the output of a photoreceiver. The photoreceiver is composed of two photosensitive areas and the shadow of a shutter moving with the beam of the balance is cast on the two photosensitive areas. The outputs of the two photosensitive areas are sent to a first subtracting circuit and an adding circuit. The output of the first subtracting circuit is corrected by the output of the adding circuit to produce signal independent of temperature change and corresponding only to the turn of the beam of the electronic balance.
    Type: Grant
    Filed: March 12, 1993
    Date of Patent: February 20, 1996
    Assignee: Shimadzu Corporation
    Inventor: Mitsumasa Uchiike
  • Patent number: 5419204
    Abstract: A force measuring instrument for determining the strength of an applied force by measuring the strength of an electromagnetic force developed so as to counterbalance the applied force, the instrument including a force coil, a displacement sensor for detecting any displacement occurring on a scale balance, an analog arithmetic unit for performing PD operation of analog detecting signals sent by the displacement sensor, a pulse converter for converting the analog signal into a signal having a frequency depending upon the magnitude of the analog signal, an up/down counter for counting up or down pulse signals from the pulse converter depending upon the polarity of the analog signal, a D/A (digital-to-analog) converter for converting the number of counts by the up/down counter into an analog signal, and wherein the sum of the output of the D/A converter and the output of the analog arithmetic unit is fed back to the force coil, thereby ensuring that the counts by the counter alone are used to determine the measur
    Type: Grant
    Filed: March 25, 1994
    Date of Patent: May 30, 1995
    Assignee: Shimadzu Corporation
    Inventors: Toshiyuki Yamaguchi, Akira Komoto
  • Patent number: 5367128
    Abstract: A novel electromagnetic balance-type weighing apparatus according to the invention includes a weighing pan/balance beam assembly (15) whose balance beam is angularly displaced as a function of the weight of an object of weighing placed on the weighing pan. An electromagnetic coil (9) is provided to generate an electromagnetic force that offsets the displacement of the balance beam of the weighing pan/balance beam assembly (15) caused by the weight of the object of weighing. A displacement detector (3, 4, 5) is provided to detect the displacement of the balance beam of the weighing pan/balance beam assembly (15). An operation unit (7) performs operations to determine a control voltage in response to the detection signal transmitted from the displacement detector (3, 4, 5). A current transducer circuit (20) generates an electric current in response to the control voltage applied to it by the operation unit (7) and supplies it to the electromagnetic coil (9).
    Type: Grant
    Filed: May 8, 1991
    Date of Patent: November 22, 1994
    Assignee: Anritsu Corporation
    Inventors: Fumihiro Tsukasa, Hideya Fujimoto, Kazuhiko Horikoshi, Osamu Tanaka, Kunio Kikuchi
  • Patent number: 5347092
    Abstract: Proposed is a compensation scale (10) in which at least one acceleration sensor (24, 25) is disposed at a movable component (14) of the scale (10) and puts out a signal to a correction signal processing arrangement (50) which determines at least one correction signal (53, 54, 56) for influencing the measuring result that appears at the output (43) as a measure for the weight or the mass (m) of the load (15) with which the movable component (14) was charged. The correction signals (53, 54, 56) eliminate the influence of translatory and rotatory interference accelerations (y, .THETA.) which act on the base plate (11) of the scale and, without being corrected, would falsify the measuring result (43) or at least unduly extend the measuring time.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: September 13, 1994
    Assignee: Robert Bosch GmbH
    Inventors: Willy Buchs, Roland Cochard, Pierre Jeannin
  • Patent number: 5315073
    Abstract: In a weighing scale including a load receiving member (2) being elastically deflectably guided by virtue of a parallel guide mechanism (3, 4) is provided an electromagnetic compensating system (12, 13, 16) for detecting the deflection which is proportional to the load. In order to achieve high precision and a simple construction, a lever (6) being located between said compensating system and said load receiving member (2) is supported on an elastic member (11), thereby preventing any positional changes in the compensating system or any non-homogeneity errors associated therewith (FIG. 1).
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: May 24, 1994
    Assignee: Mettler-Toledo (Albstadt) GmbH
    Inventors: Adolf Ast, Erwin Enzmann, Walter Holike
  • Patent number: 5270497
    Abstract: An electric balance which allows a pulse current to flow through a force coil with pulses having two kinds of duties for each period of control time, and generates an electromagnetic force at the ratio of mixture of these pulses wherein the duties are controlled so as to bring the electromagnetic force into equilibrium with a load weight, thereby enhancing the resolution of pulse current duty and achieving the production of a high-resolution electronic balance at a reduced cost.
    Type: Grant
    Filed: March 20, 1992
    Date of Patent: December 14, 1993
    Assignee: Shimadzu Corporation
    Inventor: Akira Komoto
  • Patent number: 5184690
    Abstract: In a PID-controlled electronic balance consisting essentially of a weighing pan, a pan stopper for defining the lowest position of the weighing pan, a displacement detector for detecting the displacement of the weighing pan, a PID operation circuit and an electromagnetic force transducer, the PID operation circuit is devised so as to operate, when the weighing pan has its movement kept restricted by the pan stopper, with at least one of the mathematical coefficients increased, the coefficients respectively multiplying the proportionality term integral term and differential term contained in the mathematical operation process carried out by the PID operation circuit.
    Type: Grant
    Filed: February 27, 1991
    Date of Patent: February 9, 1993
    Assignee: Shimadzu Corporation
    Inventor: Akira Komoto
  • Patent number: 5174401
    Abstract: Weighing apparatus of the electromagnetic load compensation type includes a ferromagnetic yoke member (19), that is secured at a single point to the frame (3), thereby a permit the frame to be formed of a non-ferromagnetic material, such as aluminum, having a different coefficient of expansion than the yoke member. Preferably the yoke member is secured to the frame by a single screw (33,103) arranged at the axis of symmetry of the yoke member. Owing to the small contact surface between the yoke member and the frame, the production of temperature-responsive forces which would otherwise stress or distort the apparatus to adversely affect the accuracy of the weighing operation is avoided.
    Type: Grant
    Filed: September 5, 1991
    Date of Patent: December 29, 1992
    Assignee: Mettler-Toledo AG
    Inventor: Peter Kunz
  • Patent number: 5141066
    Abstract: In order to protectively support the weighing cell of electronic weighing apparatus within a housing and thereby isolate the weighing cell from external impact and shock forces, the weighing cell is mounted on the central portion of the relatively resilient printed circuit board of the electronic load measuring circuitry, which printed circuit board is supported at its edge or corner portions in spaced relation above the bottom wall of the weighing apparatus housing.
    Type: Grant
    Filed: May 10, 1991
    Date of Patent: August 25, 1992
    Assignee: Mettler-Toledo AG
    Inventor: Ernst Strickler
  • Patent number: 5119895
    Abstract: An apparatus for generating a signal, dependent on the weight of an object, is provided for an air-suspended vehicle. Control processes of the air-suspended vehicle with automatic levelling control unit correct road conditions, such as, for example, curve inclinations, influencing the suspended weight. According to conventional apparatuses, the suspended weight is determined by the measurement of the pressure in the air suspension. This requires additional measurement and signal transfer means. The invention apparatus is to generate a signal corresponding to the suspended weight under use of the distance values stored in the automatic levelling control unit. The automatic levelling control unit (8) is structured such that it generates during automatic control an additional signal, dependent on the temporary change of the distance value. The additional signal serves as the signal dependent on the suspended weight.
    Type: Grant
    Filed: February 6, 1991
    Date of Patent: June 9, 1992
    Assignee: WABCO Westinghouse Fahrzeugbremsen GmbH
    Inventor: Detlef Gradert
  • Patent number: 5115877
    Abstract: An electronic counter having an electronic force transducer operated with a plurality of pulse currents.
    Type: Grant
    Filed: July 31, 1990
    Date of Patent: May 26, 1992
    Assignee: Shimadzu Corporation
    Inventor: Akira Komoto
  • Patent number: 5096007
    Abstract: A balance with a weighing cell includes a measurement transducer with a short travel distance and a device for protecting the load cell against dynamic and static overload. The protecting device includes a spring mounted in the flux of force between the load application and the load cell and a travel-limiting stop member fixably attached to a housing. A connecting member is inserted in series to the spring in a suspension unit. The connecting member is mounted so as to be biased by the spring against the suspension unit in the direction in which force is introduced and is fastened so as to be raisable from the suspension unit when force is introduced. The connecting member is connected to the transmission lever.
    Type: Grant
    Filed: May 7, 1990
    Date of Patent: March 17, 1992
    Assignee: Mettler Toledo AG
    Inventor: Hans-Rudolf Burkhard
  • Patent number: 5082073
    Abstract: An electronic balance with a system carrier (1) fixed to the housing, a load receiver (2) with two guide rods (3/4) which function as parallel guide, connect the load receiver to the system carried in a vertically movable manner, with four protruding arms (5, 6) which are fastened to the load receiver (2) and carry supports points (7, 8, 9, 10) for a balance scale on their ends and with a low-travel measured value receiver (14, 15) which is loaded either directly by the force of weight acting on the balance scale or with the interpositioning of a translation lever (11). The protruding arms (5, 6) comprise a central recess (19, 20) in front of their ends (17, 18) so that an upper web (21, 23) and a lower web (22, 24) remain and form a parallel guide for the particular support point (7, 8, 9, 10) of the balance scale. Each of the four support points (7, 8, 9, 10) of the balance scale is associated with a wire strain gauge (27, 28, 29, 30) located on one of the associated webs (21, 23).
    Type: Grant
    Filed: October 30, 1990
    Date of Patent: January 21, 1992
    Assignee: Sartorius AG
    Inventors: Eberhard Stadler, Matthias Eger
  • Patent number: 5055264
    Abstract: An apparatus for controlling the flows of products of decomposition in a thermogravimetric procedure such that condensation on the support for a sample and on the chamber is minimized. A mixing chamber is established about a portion of the sample support that is open to the region of the sample such that products of decomposition can enter within the hot zone about the sample. A purge gas is fed into the interior of the mixing chamber, also the hot zone, but spaced apart from the end closest to the sample. The gases commingle within the mixing chamber and are extracted from the thermogravimetric chamber via outlets in a cooler region.
    Type: Grant
    Filed: November 8, 1988
    Date of Patent: October 8, 1991
    Assignee: Cahn Instruments, Inc.
    Inventor: Jerzy P. Czarnecki
  • Patent number: 4997051
    Abstract: A compact balance with a system carrier including a vertical plate, with a balance scale carrier including a vertical plate, whereby the plane of the system carrier and the plane of the balance scale carrier are parallel to one another, with at least three guide rods which run vertically to the plane of the system carrier and connect the balance scale carrier in the form of a parallel guide to the system carrier and with a balance scale fastened in a hinged fashion to the balance scale carrier that a lever is mounted on the system carrier which lever extends parallel to the plane of the system carrier in the space surrounded by the system carrier and the balance scale carrier and that a coupling element connects the one lever arm of the lever to the balance scale carrier whereas a coil for the electromagnetic compensation of force is fastened to the other lever arm of the lever.
    Type: Grant
    Filed: September 11, 1989
    Date of Patent: March 5, 1991
    Assignee: Sartorius GmbH
    Inventors: Gunther Maaz, Eduard Bierich, Klaus Dardat
  • Patent number: 4991973
    Abstract: An electronic balance with scale on top having a drive means for a magnetic agitator which integral onto the balance scale. This enables the work steps of agitating and weighing to be performed simultaneously and by the same device.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: February 12, 1991
    Assignee: Sartorius AG
    Inventors: Gunther Maaz, Klaus Dardat, Alfred Klauer
  • Patent number: 4938301
    Abstract: In an electronic balance with a scale on top with two guide rods which connect a load receiver to a system carrier fixed to the housing as parallel guide, with at least one translation lever which is connected to the system carrier by means of two springs and with a coupling element (9) which transfers the force corresponding to the mass of the weighed material from the load receiver to the shorter lever arm of the translation lever while the counteracting force imposes on the longer lever arm of the translation lever.
    Type: Grant
    Filed: November 8, 1989
    Date of Patent: July 3, 1990
    Assignee: Sartorius GmbH
    Inventors: Eberhard Stadler, Matthias Eger, Gottfried Nolte, Eberhard Lubke
  • Patent number: 4938300
    Abstract: A weighing apparatus comprising a first self-contained weighing device (1) including a first farme (2), a first load-receiving member (5) connected by a parallel guide arrangement for movement from a normal no-load position relative to the first frame, a load-responsive device (10) for indicating the magnitude of an applied load as a function of the movement of the first load receiving member, and a first motion-transmitting lever (7) connected between the first load receiving member and the position-responsive device, characterized by the provision of a second load receiving member (16,28) to which the load to be measured is applied, and a second pivotally mounted motion-transmitting lever (17,30) connecting the second load receiving member, thereby to provide a resultant load range that is higher than that of the first weighing device. Thus, various increased load ranges may be achieved starting from a standard self-contained weighing apparatus.
    Type: Grant
    Filed: October 25, 1989
    Date of Patent: July 3, 1990
    Assignee: Mettler Instrumente AG
    Inventor: Peter Kunz
  • Patent number: 4930588
    Abstract: An electronic balance with a weighing scale which is connected via a parallel guide to a system carrier, and with a translation lever which is rotatably mounted on the system carrier and onto the shorter lever arm of which the force of the weight acting on the balance scale is transferred via a coupling element and on the longer arm of which the coil of an electromagnetic compensation of force is fastened, that at least one spring touches the translation lever for the purpose of astatization, the line of application of which spring passes through the point of rotation of the translation lever. This results in a compact design and a good efficiency of astatization. It is advantageous to use a wire or a band and/or a laterally jutting-out projection on the translation lever as spring.
    Type: Grant
    Filed: August 28, 1989
    Date of Patent: June 5, 1990
    Assignee: Sartorius GmbH
    Inventors: Otto Kuhlmann, Walter Sodler, Eberhard Stadler
  • Patent number: 4878552
    Abstract: For use with weighting apparatus of the electromagnetic-load-compensation type, where a stirring or other magnet creating an external magnetic field is disposed near such apparatus, a protective shield is interposed between that magnet and the apparatus, in flux-transmitting relation to the magnet, so as to shield the apparatus from the externally created field. The shield is formed from ferromagnetic material of sufficiently high permeability to provide a path of least reluctance for transmitting flux from the external field, thereby preventing such flux from interfering with intended operation of the apparatus.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: November 7, 1989
    Assignee: Eastman Kodak Company
    Inventors: Charles H. Gebo, Bradley C. Roth
  • Patent number: 4875534
    Abstract: Weighing apparatus of the load compensation type includes a source of constant current pulses the duration of which is determined by a regulating signal in response to the position of the load receiver relative to the frame, thereby to maintain the load receiver in an initial or zero position during the application thereto of a load to be measured. The regulating circuit includes a PID regulating amplifier that produces a differential signal (D) and a proportional and integral signal (PI). The PI signal controls the operation of a switch that determines the duration of the constant current pulses, and the D signal modulates the amplitude of the constant current from which the pulses are formed. In this manner of using the differential regulating signal component (D), the influence of various deleterious effects on the weighing apparatus, such as vibration, is avoided.
    Type: Grant
    Filed: May 19, 1989
    Date of Patent: October 24, 1989
    Assignee: Mettler Instruments AG
    Inventor: Peter Kunz
  • Patent number: 4858711
    Abstract: An electronic balance includes a measuring cell for electromagnetic load compensation. The measuring cell and a load receiving member of the balance are arranged in an inner housing which is closed to all sides with the exception of an opening for a receiving cone of the load receiving member. The inner housing is mounted in the balance housing so as to be spaced apart from the walls, the base and the cover of the balance housing. A circumferentially extending partition wall is tightly sealingly attached to the bottom and the cover of the balance housing. The partition wall is mounted between the inner housing and the walls of the balance housing.
    Type: Grant
    Filed: December 16, 1988
    Date of Patent: August 22, 1989
    Assignee: Mettler Instrumente AG
    Inventor: Peter Kunz
  • Patent number: 4836293
    Abstract: For use with weighing apparatus of the electromagnetic-load-compensation type, where a stirring or other magnet creating an external magnetic field is disposed near such apparatus, a protective shield is interposed between that magnet and the apparatus, in flux-transmitting relation to the magnet, so as to shield the apparatus from the externally created field. The shield is formed from ferromagnetic material of sufficiently high permeability of provide a path of least reluctance for transmitting flux from the external field, thereby preventing such flux from interfering with intended operation of the apparatus.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: June 6, 1989
    Assignee: Eastman Kodak Company
    Inventors: Charles H. Gebo, Bradley C. Roth
  • Patent number: 4825968
    Abstract: There is disclosed a balance based on the principle of the electromagnetic compensation of force with a cylindrical permanent magnet system, with a magnet cover and with a coil for generating the counteracting force that an emitter and a receiver of the optical position sensor be housed inside the magnet cover. The slit diaphragm of the optical position sensor, which extends from below into the area between emitter and receiver, then forms a compact unit with a carrier, e.g., the end of a translation lever, and with a coil and mutual shifts at temperature changes and temperature gradients occur only to a minimal extent.
    Type: Grant
    Filed: December 22, 1987
    Date of Patent: May 2, 1989
    Assignee: Sartorius GmbH
    Inventors: Gunther Maaz, Udo Wedeken, Eduard Bierich, Eberhard Stadler
  • Patent number: 4817745
    Abstract: A thermogravimetric balance includes a bridge assembly carried by a torque motor, said bridge assembly having, at one end, riser mechanism for carrying a sample pan, and at the other end, first magnetic means for regulating said bridge; further magnetic means positioned intermediate said riser and said first magnetic means for further regulating said bridge; and a furnace device movably encompassing the sample pan.
    Type: Grant
    Filed: December 21, 1987
    Date of Patent: April 4, 1989
    Inventor: Joseph E. Beshoory
  • Patent number: 4813505
    Abstract: It is disclosed for a balance with a scale on top based on the principle of the electromagnetic compensation of force with a system carrier fixed to the housing, with a load receiver, with two guide rods which connect the load receiver to the system carrier in a vertically movable direction as parallel guide, whereby the stem carrier, the two guide rods and the load receiver are designed as a one-piece casting, with a translation lever and with a coupling element between load receiver and translation lever, whereby the force from the load receiver corresponding to the mass of the weighed material is transferred via the coupling element to the shorter lever arm of the translation lever and the coil of the electromagnetic compensation of force is fastened to the longer lever arm of the translation lever that the system carrier comprise lateral projections which extend into the area between the guide rod arms.
    Type: Grant
    Filed: January 12, 1988
    Date of Patent: March 21, 1989
    Assignee: Sartorius GmbH
    Inventors: Walter Sodler, Eberhard Lubke, Otto Kuhlmann
  • Patent number: 4802541
    Abstract: A weighing scale capable of weighing articles in a rapid and accurate fashion. The tray of the scale is supported by at least one spring and becomes vertically displaced in proportion to the weight of an article placed thereon. A voice coil is used to bias the tray to its original position, and the weight of the article is determined by measuring the current in the voice coil.
    Type: Grant
    Filed: March 11, 1988
    Date of Patent: February 7, 1989
    Assignee: Pitney Bowes Inc.
    Inventors: Feliks Bator, Kevin D. Hunter, Robert T. Durst, Jr.
  • Patent number: 4799561
    Abstract: An electronic balance in which a means for transmitting a force due to a weight loaded on a weighting pan to a weight sensing means is made of one metallic block from which are integratedly cut out a Roberval mechanism, a lever and a connecting portion for connecting the lever to the Roberval mechanism.
    Type: Grant
    Filed: May 9, 1988
    Date of Patent: January 24, 1989
    Assignee: Shimadzu Corporation
    Inventor: Akira Komoto
  • Patent number: 4754823
    Abstract: Weighing apparatus of the electromagnetic load compensation type includes an improved variable (C.sub.x) and reference (C.sub.o) capacitance comparison arrangement for sensing the position of the movable load receiver member relative to the stationary base member. The comparison arrangement supplies an error signal that is proportional to the capacity ratio, which error is used to control a compensation current (i.sub.L) that is supplied to a compensation coil to maintain the movable load receiver member at its initial zero position. The variable capacitance is produced by a variable air capacitor including a first pair of stationary capacitor plate electrodes (10, 12), and a movable plate-like metal shield or screen which extends partially between the first pair of electrodes in accordance with movement of the load receiver member.The position sensor arrangement is simple to construct and install, and affords precise measurement during use.
    Type: Grant
    Filed: June 12, 1987
    Date of Patent: July 5, 1988
    Assignee: Mettler Instrumente AG
    Inventor: Arthur Baumann
  • Patent number: 4730683
    Abstract: Weighing apparatus of the electromagnetic load compensation type is provided with a movable coil arranged in the air gap of a permanent magnet system, and which includes a load-compensation winding through which flows a load-dependent compensation current. As a temperature sensor for measuring the coil temperature, use is made of the coil, specifically, either the load winding itself or an additional winding that is in thermal contact with it. A resistance measuring device determines its temperature-dependent resistance from the voltage and the current on or in the winding. Accurate and real-time measurement of the coil temperature as a measure for controlling the compensation of its influence on the measurement reading is possible in this way.
    Type: Grant
    Filed: March 3, 1987
    Date of Patent: March 15, 1988
    Assignee: Mettler Instrumente AG
    Inventor: Arthur Reichmuth
  • Patent number: 4722409
    Abstract: A compact weighing apparatus of the electromagnetic load compensation type is disclosed including a permanent magnet system having a U-shaped soft iron yoke, and a pair of highly coercive permanent magnets of parallelepiped configuration mounted in opposed relation between the adjacent surfaces of the leg portions of the yoke. The compensation coil is mounted for movement between, and in a direction parallel with, the yoke leg portions, the coil having a rectangular cross sectional configuration to define longer coil turn sides arranged adjacent the magnets, respectively. The lever that connects the compensation coil with the load receiving member contains a stepped recess that receives at least a portion of one of the load receiver guide means, thereby to achieve further compactness of the components of the weighing apparatus.
    Type: Grant
    Filed: May 18, 1987
    Date of Patent: February 2, 1988
    Inventor: Peter Kunz
  • Patent number: 4705127
    Abstract: The position of the movable member relative to the stationary member of weighing apparatus of the electromagnetic load-compensation type is sensed by a variable-capacity alternating-current bridge network, use being made of two pairs of coplanar capacitive plate electrodes arranged in successively spaced opposed relation between planar parallel electrically-grounded surfaces of the movable and stationary members of the weighing apparatus. Opposed electrodes of each pair are connected in the bridge network to define two capacitive voltage dividers across the center points of which is developed an electrical signal corresponding with the deviation of the movable member from its zero position.The position sensor is manufactured in a simple manner and affords precise operation. All of the circuit connections are to fixed plate-type capacitive electrodes that may be mounted on a carrier member immediately adjacent the other electronic equipment.
    Type: Grant
    Filed: March 13, 1987
    Date of Patent: November 10, 1987
    Inventor: Peter Kunz
  • Patent number: 4699228
    Abstract: A new mass transducer with electromagnetic compensation is described, comprising a load-detection part, fitted with a coil fixed to the load levers, a reference part comprising a sample weight and a second coil (called reference coil) fixed to the reference levers, a magnetic unit (yoke) with permanent magnets in the air gap whereof the coils are placed coaxially, free to move independently of one another, a control device for keeping the load coil and the reference coil in place and a device for comparing the current flowing through the coils. According to the invention, the coils are of the flattened toric type, their biggest dimension being perpendicular to the longitudinal axis of the lever arm of the load levers and the winding axis X--X of the coil lined up with the force axis.
    Type: Grant
    Filed: June 25, 1986
    Date of Patent: October 13, 1987
    Assignees: Dataprocess S.p.A., Italora S.p.A.
    Inventors: Piercarlo Mustarelli, Franco Lupoli, Emilio Negri
  • Patent number: 4678048
    Abstract: The invention relates to an apparatus for the contactless coupling of a suspended part 9, provided with a magnet 12 and located in a housing 6 to a force measuring device outside housing 6 and which is provided with a controllable electromagnet 1. Unlike in known apparatuses of this type, the position change of the suspended part 9 is recorded in absolute terms with respect to housing 6 and used for controlling electromagnet 1. This gives greater freedom in the design of housing 6, which can now be designed for a wider temperature and pressure range than hitherto, because no longer is it necessary to take account of a distance measurement through the housing wall.
    Type: Grant
    Filed: July 30, 1985
    Date of Patent: July 7, 1987
    Inventors: Hans-Wilhelm Losch, Rainer Kleinrahm, Norbert Pieperbeck, Wolfgang Wagner
  • Patent number: 4674582
    Abstract: A scale of the platform type includes a base frame, a lever mechanism for force-transmission connected to the base frame, and including a plurality of two-armed levers, a weighing platform supported by the two-armed levers, a measurement transducer disposed within the base frame and adapted for generating signals substantially proportional to a weight placed on the weighing platform, and a movable load-carrying frame surrounding the base frame, and wherein each two-armed lever is pivoted on the base frame. This concept permits attainment of scales of very low height, hardly sensitive to corner loads, namely loads offset from the center of the scale, and which have a high degree of resolution. The scale may be used for precision weighing, and may have a load region e.g. within a range from about 10 kg to about 100 kg.
    Type: Grant
    Filed: August 9, 1985
    Date of Patent: June 23, 1987
    Assignee: Mettler Instrumente AG
    Inventor: Peter Kunz
  • Patent number: 4656599
    Abstract: It is necessary, when high requirements are demanded from balances, that the effect of different disturbance variables such as, e.g., temperature and/or moisture on the measuring system be corrected. To this end, temperature and moisture sensors are used from whose output signal correction values are calculated. The invention suggests that a storage area be provided into which the instantaneous measured results of these sensors are stored in succession, where they remain stored for a set time. This data stemming from different times, evaluated with set weighting factors, could then be used to calculate the corrections. This makes it possible to obtain a good correction of changing disturbances even with a different behavior in time of sensors and measuring system.
    Type: Grant
    Filed: October 26, 1984
    Date of Patent: April 7, 1987
    Assignee: Sartorius GmbH
    Inventors: Erich Knothe, Franz-Josef Melcher, Jurgen Ober, Christoph Berg, Klaus Dardat, Eduard Bierich, Gunther Maaz
  • Patent number: 4627505
    Abstract: Weighing apparatus of the load compensation type including a position sensing circuit for supplying current pulses from a constant current source to a compensation coil to return the load platform--after the application of a load thereto--toward its initial no-load position relative to the frame, the magnitude of the compensation current, as displayed by digital readout means, being a function of the mass of the applied load, characterized by the provision of an auxiliary analog-to-digital converter for digitalizing a signal corresponding with the compensation current, and a comparison circuit for comparing the digitalized signal with a standard value and for generating an error signal if the comparison result exceeds a given value. In addition to monitoring the constant current source, other components (such as temperature sensor, current switch and compensation coil) may be monitored by corresponding comparisons.
    Type: Grant
    Filed: June 12, 1985
    Date of Patent: December 9, 1986
    Assignee: Mettler Instrumente AG
    Inventor: Peter Kunz