Tension-compression Patents (Class 73/796)
  • Patent number: 10060833
    Abstract: A shape memory effect measuring apparatus is provided that is useful for tensile stress, strain and recovery stress measurement. The apparatus includes a load cell, a linear variable displacement transducer, a temperature sensor, a rigid platform, a computer-based data recorder and a processing system a load frame, grips to hold sample, and a liquid bath. The liquid bath is mounted on the rigid stand platform to hold the liquid bath. A uniform temperature of liquid is attained by controlled heating and stirring arrangement. The computer-based processing system may be used to monitor and control the desired temperature of the sample. A change in length of a specimen and stress generated during expansion thereof may be recorded, from which strain and stress may be calculated using the apparatus.
    Type: Grant
    Filed: May 17, 2016
    Date of Patent: August 28, 2018
    Assignee: Council of Scientific & Industrial Research
    Inventors: Syed Azhar Rasheed Hashmi, Hari Narayan Bhargaw, Ajay Naik, Jagdish Prasad Pandey, Mulayam Singh Yadav, Navin Chand
  • Patent number: 9455608
    Abstract: A testing apparatus includes a crosshead and a head assembly. The head assembly includes a head cover having an interior volume. An electric actuator, controls and other electric components are located within the interior volume, wherein the motor, controls and other electric components generates heat when energized. A divider within the interior volume separates a first volume from a second volume. The first volume includes the heat generating electric motor, controls and electric components and the second volume contains substantially no heat generating components. The head assembly includes at least one fan within the second volume that draws cool air from outside the head cover and forces the cool air through the second volume and into the first volume to remove heat.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: September 27, 2016
    Assignee: MTS Systems Corporation
    Inventors: Bradley Dean Schulz, Tyler B. Kuhlmann, Paul M. Krueger, Richard Leo Taylor
  • Patent number: 9389131
    Abstract: A device, assembly and method for clamping single fibers that utilizes snubbing surfaces simultaneously with magnetic gripping action are described. The device can be fabricated at miniature sizes with very low mass and volume, which are desirable requirements for testing of small fibers in highly sensitive force-transducing load frames. Advantageously, the combined use of snubbing surfaces and magnetic gripping greatly reduces the probability of slippage or fiber failure at the grip during testing.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: July 12, 2016
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Eric D. Wetzel
  • Publication number: 20140326073
    Abstract: Systems and methods provide for testing a cement by applying force in a first direction until the first portion of the cement sample fails in compression or tension; and applying force a second direction opposite the first direction until the second portion of the cement sample fails in tension or compression.
    Type: Application
    Filed: July 21, 2014
    Publication date: November 6, 2014
    Inventors: David Leon Meadows, Robert Phillip Darbe, Walmy Cuello Jimenez, Robert Lee Browning
  • Patent number: 8766811
    Abstract: A compression testing assembly for compression testing of a test material includes a testing stage with a first surface and a second surface. The test material is disposed between the first and second surfaces. The assembly also includes a thickness detector that automatically detects a thickness of the test material. Moreover, the assembly includes an actuator that moves at least one of the first and second surfaces toward the other of the first and second surfaces to compress the test material to a predetermined percentage of the detected thickness of the test material. Additionally, the assembly includes a load detector that detects a compression load of the test material and that detects a change in the compression load over time.
    Type: Grant
    Filed: January 21, 2011
    Date of Patent: July 1, 2014
    Assignee: NIKE, Inc.
    Inventors: Juan-Pier A. Spampinato, Edward F. Wachtel
  • Patent number: 8714016
    Abstract: A method and apparatus for generating a tension wave. A beam of coherent light is directed to an absorber surface of a transducer structure. A compression wave is generated within the transducer structure. The compression wave is reflected on a reflecting surface of the transducer structure to form the tension wave. The tension wave is directed through a test object in a desired direction using a configuration of the reflecting surface relative to the test object.
    Type: Grant
    Filed: February 1, 2012
    Date of Patent: May 6, 2014
    Assignee: The Boeing Company
    Inventors: Alan Frank Stewart, Richard H. Bossi, Clarence L. Gordon, III
  • Patent number: 8132447
    Abstract: A testing machine includes a stand and a test device. The stand includes a base, box frame, a slide device driven to slide by a motor, and a control system controls the force applied on the test specimen. The test device is coupled at the slide device for performing various hardness tests consisting of Rockwell hardness test, Vickers hardness test, Brinell hardness test, micro-hardness test, and tension-compression test. The test device includes a force sensor and a data processing circuit converting an analog signal of the force sensor into digital data to interface with the control system.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: March 13, 2012
    Inventors: Shaoming Wu, Richard Wu
  • Patent number: 7757564
    Abstract: The present invention includes: a pair of columnar members 12 disposed on both sides of a specimen piece SP; a crosshead 15, bridging the pair of columnar members 12, that applies a load to the specimen piece SP by moving in a direction of a longitudinal axis of the columnar member 12 and; a movable member 31 disposed at a side of the columnar member 12, extending in the direction of the longitudinal axis and elastically supported so as to be movable in the direction of the longitudinal axis; a striker 35, integrally attached to the movable member 31 so as to be displaceable in the direction of the longitudinal direction, that is allowed to be pushed by a movement of the crosshead 15 to a position where the striker is attached; a position sensor 38 that detects a movement of the movable member 31 by being pushed by the striker 35; a limitation member 34 that limits the position where the striker 35 is attached; and an elastic member 36 that supports the striker 35 so that the striker 35 is capable of relative
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: July 20, 2010
    Assignee: Shimadzu Corporation
    Inventor: Masaki Kaneda
  • Publication number: 20090199651
    Abstract: A gripper and a driving method using the same are disclosed, wherein an actuator has a configuration combined with a piezoelectric operating unit and a bending structure, whereby an amount of variation of a gap between fingers are amplified more than that of the piezoelectric operating unit by generating a movement of the fingers perpendicular to a movement direction of the piezoelectric operating unit, and wherein the gripper having arms including a strain gauge sensor can precisely measure a force applied to a micro object.
    Type: Application
    Filed: February 2, 2009
    Publication date: August 13, 2009
    Inventors: Kwang Bum Park, Joon Shik Park, Hyo Derk Park
  • Publication number: 20090120199
    Abstract: The crosshead for a universal testing machine includes a interior face which is formed at angle to the front face which is typically about 17°. A wedge pocket is machined with walls perpendicular to the interior face, and therefore at an angle other than perpendicular to the front surface of the crosshead. This allows a rectangular steel plate to be oriented to match the machine column locations. Therefore, the material cost is significantly reduced as no special casting shape is required.
    Type: Application
    Filed: November 9, 2007
    Publication date: May 14, 2009
    Inventor: John Hemmerlin
  • Patent number: 7509874
    Abstract: The apparatus has an elongate and vertically running carrier (90) for pressure sensors (50), which precedes a group of levers (71 ). The cross section of this carrier (90) is arcuate, so that it has two flanks (93, 94 ). During the testing of a leg garment (80), this carrier (90) simulates the region of the shin. The apparatus has, furthermore, moldings or stays (88) which are carried by the levers and which simulate the rear face of the calf or of the thigh of a leg. The width of these stays corresponds to the width of the calf or of the thigh of a leg. The apparatus also comprises two longitudinally running groups (50) of pressure sensors, one of which is in each case assigned to outside of one of the flanks (93, 94) of the carrier (90). The leg garment (80) to be tested, in order to test it, is slipped over this apparatus in such a way that it lies on the outer faces both of the carrier (90) and of the stays and exerts pressure on the pressure sensors (51).
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: March 31, 2009
    Assignee: Salzmann AG
    Inventors: Daniel Kuenzli, Walter Braun, Muck Ruettiger
  • Patent number: 7510866
    Abstract: A hybrid bioreactor for cell culture is disclosed. To simultaneously apply compressive strain for cell differentiation and shear strain for cell proliferation to cells, the hybrid bioreactor includes a plurality of reactor tube assemblies (100), a compressive strain motor (5), a shear strain motor (25), a lower anchor mount (20) having a plurality of toothed anchors (70) to respectively anchor the lower ends of the reactor tube assemblies (100) to the lower anchor mount (20), a ball screw (90) operated in conjunction with the compressive strain motor (5), an upper anchor mount (60) which engages with the ball screw (90) to vertically move upward and downward and having a plurality of compressive strain anchors (80) to anchor the upper ends of the reactor tube assemblies (100) to the upper anchor mount (60), a power transmission unit to transmit the rotating force of the shear strain motor (25) to the toothed anchors (70).
    Type: Grant
    Filed: October 29, 2003
    Date of Patent: March 31, 2009
    Assignee: Korea Institute of Science and Technology
    Inventors: Kuiwon Choi, Tae Soo Bae, Jung Kyu Kim, Chang Yang Lee
  • Patent number: 7441465
    Abstract: A method and system are provided for obtaining force-displacement responses for a specimen or sample of material. The sample is supported with a spanning portion spanning in an environment between at least three points not in a line, wherein the points are fixed relative to each other, and wherein the spanning portion is capable of displacement relative to the points. An oscillating mechanical excitation at at least one frequency and at at least one known amplitude is applied to the spanning portion. In addition, at least one other mechanical excitation is also applied to the spanning portion independently of the oscillating mechanical excitation.
    Type: Grant
    Filed: June 1, 2007
    Date of Patent: October 28, 2008
    Assignee: Agilent Technologies, Inc.
    Inventors: Warren C. Oliver, Erik G. Herbert
  • Patent number: 7409869
    Abstract: A method for evaluating thermal fatigue resistance for a welding consumable alloy can include the following steps: placing a test specimen of a welding consumable alloy in a testing device such that a tensile load and a compressive load can be introduced to the test specimen; heating the test specimen to a first temperature; applying a compressive force to the test specimen while heating the test specimen; cooling the test specimen to a second temperature; and applying a tensile force to the test specimen while cooling the test specimen.
    Type: Grant
    Filed: May 18, 2005
    Date of Patent: August 12, 2008
    Assignee: Lincol Global, Inc.
    Inventors: Damian J. Kotecki, Sudarsanam S. Babu
  • Publication number: 20080011094
    Abstract: A testing system includes a soft reaction structure formed by column assemblies, a base and a crosshead. Compliant devices are disposed between the column assemblies and the base and/or the crosshead to isolate interaction of these components and reduce structural vibration mode excitation.
    Type: Application
    Filed: June 29, 2006
    Publication date: January 17, 2008
    Applicant: MTS Systems Corporation
    Inventors: Byron J. Saari, Craig L. Campbell
  • Patent number: 7038592
    Abstract: A method and a device for detection of physical or approximately physical bottom contact for objects, for instance fishing tackles, which are dragged closely above or on a sea bottom, said method consisting of sensoring an alteration of a force acting on a tension sensor (4) as a consequence of a mass (7) coupled to the tension sensor (4) coming into physical contact with the bottom, said alteration being used as indication of bottom contact, and that frictional forces (F2) being due to the dragging of the mass (7) along the bottom mainly are taken up by means of a tension release means (8). The device comprise the mass (7) being suspended in a tension sensor (4) in such a manner that the sensor (4) is actuated by bottom contact, and at least one tension release means (8) connected to the mass (7) and adapted to take up forces caused by dragging of the mass above the bottom.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: May 2, 2006
    Assignee: Simrad AS
    Inventors: Kjell Ramberg, Bjørn Faber
  • Patent number: 7000484
    Abstract: A beam transducer employs a linear bearing which surrounds the active element of the transducer which is the beam. One end of the bearing is welded to the inactive end of the load beam. The other end of the bearing is not welded, allowing the active end of the beam to move freely. The linear bearing eliminates friction and jamming which will cause inaccurate load measurement, but the ability to allow the active element to move freely with one end free enables the load beam sensitivity to be maximized. The free end is sealed environmentally by employing a flexible metal membrane or diaphragm which is welded between the bearing end and the load beam. This configuration provides a hermetic seal to protect the load beam and the sensitive gages which are placed on the load beam.
    Type: Grant
    Filed: March 25, 2003
    Date of Patent: February 21, 2006
    Assignee: Kulite Semiconductor Products, Inc.
    Inventors: Anthony D. Kurtz, Adam Kane
  • Patent number: 6925890
    Abstract: Anchor chain load measurement arrangement for measuring the reactive load in structures which support an anchor chain. In one arrangement, standard resistance compression load cells are mounted directly in the load path between a chain retainer and a trunnion block. In another arrangement a non-contact sensor is positioned to measure the deflection of an inner portion of the trunnion block with respect to a supported outer portion of the trunnion block. The non-contact sensor can be based on capacitive, eddy current or optical measurement principles.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: August 9, 2005
    Assignee: FMC Technologies, Inc.
    Inventor: William L. Fontenot
  • Publication number: 20040187594
    Abstract: A beam transducer employs a linear bearing which surrounds the active element of the transducer which is the beam. One end of the bearing is welded to the inactive end of the load beam. The other end of the bearing is not welded, allowing the active end of the beam to move freely. The linear bearing eliminates friction and jamming which will cause inaccurate load measurement, but the ability to allow the active element to move freely with one end free enables the load beam sensitivity to be maximized. The free end is sealed environmentally by employing a flexible metal membrane or diaphragm which is welded between the bearing end and the load beam. This configuration provides a hermetic seal to protect the load beam and the sensitive gages which are placed on the load beam.
    Type: Application
    Filed: March 25, 2003
    Publication date: September 30, 2004
    Inventors: Anthony D. Kurtz, Adam Kane
  • Publication number: 20040144180
    Abstract: A load increasing in a stepped manner from an initial load is applied to a test piece (4) of material in order to examine mechanical properties of the material by applied load, but the load having a next step load added thereto is applied to the test piece after it is confirmed that the variation of strain within a unit time applied to the test piece in the load (Wn) applied in each step falls within a predetermined value whereby there are measured physical variation and time variation in the load applied in each step. The load applied to the test piece is preferably kept at a constant value and the applied load (Wn) and and time variation are preferably recorded.
    Type: Application
    Filed: November 25, 2003
    Publication date: July 29, 2004
    Inventor: Senji Imamura
  • Patent number: 6679124
    Abstract: A material testing system includes a base and first and second specimen holders. A first displacement sensor measures displacement of the first specimen holder relative to the base. In addition, a second displacement sensor measures displacement of the second specimen holder relative to the base.
    Type: Grant
    Filed: June 6, 2001
    Date of Patent: January 20, 2004
    Assignee: MTS Systems Corporation
    Inventor: Warren C. Oliver
  • Patent number: 6666097
    Abstract: A force measuring device and method for determining a force required to move a cart. The force measuring device includes a force generating device, a load member, a load cell, and a controller. The force generating device is connected to the load member and moves the load member toward or away from the cart so as to apply pushing or pulling forces to the cart. The load cell is disposed between the load member and the cart, and transmits sensed force data to the controller. During a test, the controller collects the force data from the load cell. By testing carts of various configurations under all expected loading conditions, the performance of each cart configuration can be experimentally determined. The performance data is assembled in a database to permit a user to identify an optimum cart for an intended application.
    Type: Grant
    Filed: December 27, 2001
    Date of Patent: December 23, 2003
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventor: Robert T. Smith
  • Patent number: 6647802
    Abstract: A creep testing fixture and method for applying a precise amount of constant tensile stress to a creep test specimen to allow for precise measurement of creep in the test specimen. The fixture includes first and second mounting grips for holding opposite ends of a test specimen. A frame supports the mounting grips for relative reciprocal movement toward and away from each other. A tensile spring is connected between the first and second mounting grips. The frame subjects a test specimen held between the mounting grips to tensile stress in response to axially inward force that the tensile spring applies to the frame.
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: November 18, 2003
    Assignee: Automotive Composites Consortium
    Inventors: Kelly Willson-Hackworth, Steven George Luckey, Jr., Daniel Q. Houston, Edward M. Hagerman, John M. Henshaw
  • Publication number: 20030121333
    Abstract: A force measuring device and method for determining a force required to move a cart. The force measuring device includes a force generating device, a load member, a load cell, and a controller. The force generating device is connected to the load member and moves the load member toward or away from the cart so as to apply pushing or pulling forces to the cart. The load cell is disposed between the load member and the cart, and transmits sensed force data to the controller. During a test, the controller collects the force data from the load cell. By testing carts of various configurations under all expected loading conditions, the performance of each cart configuration can be experimentally determined. The performance data is assembled in a database to permit a user to identify an optimum cart for an intended application.
    Type: Application
    Filed: December 27, 2001
    Publication date: July 3, 2003
    Inventor: Robert T. Smith
  • Patent number: 6553320
    Abstract: A method for testing the stability of vertically braced masts wherein the relevant mast is subjected to the load of a bending force starting from a defined initial value, and increasing to a maximum pre-set testing force above its bracing, the mast thereby being laterally displaced. The load is then removed from the mast and is subjected to a restoring force which reduces to zero. The mast is evaluated in conjunction with the load removal procedure to determine damage to the mast and/or its bracing. The mast is subjected to an additional bending force in the opposite direction of the first bending force, and the load is once again removed from the mast in a second test procedure. A possible remaining displacement of the mast/bracing system is evaluated in conjunction with the highest mast loads to determine the type of possible damage to the mast.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: April 22, 2003
    Inventors: Mathias Roch, Oliver Roch
  • Publication number: 20020174725
    Abstract: The present invention aim at providing a releasing/hooking force meter, which measures the releasing/hooking force of the leader pin of the magnetic tape cartridge.
    Type: Application
    Filed: May 7, 2002
    Publication date: November 28, 2002
    Applicant: FUJI PHOTO FILM CO., LTD.
    Inventor: Yusuke Ishihara
  • Patent number: 6446510
    Abstract: A force transducer assembly for measuring compressive and tensile loads applied to a force transmission device, the assembly includes a housing, a sleeve assembly and a sensor device. The housing has a hollow interior. The sleeve assembly is coupled within the interior of the housing. The sensor device is secured within the interior of the housing between a portion of the sleeve assembly and a portion of the housing. The sensor device includes first and second sensors each including an isolation diaphragm at least partially defining an oil-filled cavity, and a piezoresistive sensor positioned so as to be effected by a change in pressure in the oil-filled cavity. When a first force is applied to the apparatus in a first direction via the force transmission device, one of the isolation diaphragms is deflectable in response thereto, and when a second force is applied in a second direction opposite to the first direction, the other of the isolation diaphragms is deflectable in response thereto.
    Type: Grant
    Filed: July 24, 2000
    Date of Patent: September 10, 2002
    Assignee: Kulite Semiconductor Products, Inc.
    Inventors: Anthony D. Kurtz, Robert Gardner, Richard Martin, Lou DeRosa, Estelle Anselmo
  • Publication number: 20020104380
    Abstract: A device to monitor and quantify the tension and compression forces acting on a well logging instrument string during deployment. The device eliminates the undesirable effects of downhole hydrostatic pressure on the sensors, and eliminates the need for a costly, complex, and high maintenance hydraulic pressure equalizing system in the force gage assembly. The device provides improved measurement accuracy, provides enhanced reliability and longer life of the sensors, and allows lower cost of manufacture and maintenance.
    Type: Application
    Filed: February 8, 2001
    Publication date: August 8, 2002
    Inventor: James E. Brewer
  • Patent number: 6341529
    Abstract: A method and apparatus for estimating the degree of cleanliness of a substrate surface, particularly an inorganic surface used in the manufacturing of electronic components. A soft metal, eg., indium, probe is pressed against the substrate surface to be tested and then withdrawn. A tensile force, caused by the surface energies of the two materials, opposes the separation. If the inorganic surface is contaminated by any organic material, this force will be greatly affected. The tensile force is measured with a load cell and the displacement from the expected value will indicate the degree of contamination of the substrate surface.
    Type: Grant
    Filed: August 4, 1999
    Date of Patent: January 29, 2002
    Assignee: International Business Machines Corporation
    Inventor: Donato Casati
  • Patent number: 6339962
    Abstract: A force sensor has an elastically deformable carrier (10; 110) which absorbs the force to be measured and on which there are a first and a second strain measurement element (21, 31; 121, 131) arranged such that the elastic deformation of the carrier (10; 110) which is caused by the force leads to different elongations in the two strain measurement elements (21, 31; 121, 131). This difference in elongations is used as a measure for the force to be measured. The force sensor as claimed in the invention is largely immune to disruptive ambient influences such as temperature changes, electromagnetic interference, tensile, compressive and/or shearing forces in the lengthwise direction of the tube, shearing forces transversely to the lengthwise direction of the tube, etc. Wheel load scales with several force sensors as claimed in the invention have such a short response time that it enables measurement of the wheel loads of moving vehicles.
    Type: Grant
    Filed: May 11, 2000
    Date of Patent: January 22, 2002
    Assignee: Haenni Instruments AG
    Inventors: Felix Scheuter, Christian Maurer
  • Patent number: 6314376
    Abstract: According to the method suggested, the mast is submitted to an increasing force, and both this force and the deflection path are correlated to establish a characteristic load line. After it has been loaded, the mast is again relieved from the load, a characteristic load relief line is determined and the return force is correlated to the decreasing return path. The finds related to the mast solidity and anchorage are based on the tracing of the characteristic load relief line and the comparison with the characteristic load line.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: November 6, 2001
    Inventors: Mathias Roch, Oliver Roch
  • Patent number: 6308577
    Abstract: A circuit and method for correcting a sense signal of a sensor (100) where the sense signal is reduced by a negative nonlinear error component introduced by membrane stress in a sensor structure (101). A first transducer (103) is disposed at a location (203) having substantial bending stress to produce a sense signal having a linear component and the nonlinear error component. A second transducer (102) is disposed at a location (202) with substantially zero bending stress to produce a sense signal having the nonlinear error component but a substantially zero linear component. The sense signal from the second transducer (102) is added to the sense signal from the first transducer (103) to correct the nonlinear error for producing a linear output sense signal (VOUT) of the sensor (100) which is representative of the physical condition.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: October 30, 2001
    Assignee: Motorola, Inc.
    Inventors: Ira E. Baskett, Andrew C. McNeil
  • Patent number: 6205862
    Abstract: A viscoelasticity measurement instrument having a support whose position can be varied relative to a sample holder for holding an end portion of a sample. A detection rod is resiliently held to the support, and holds a part of the sample. When a DC or AC force is applied to the detection rod, the displacement of the detection rod relative to the support is detected. The position of the support is varied or the DC force is varied to restore the displacement to zero. In this manner, the effect of the elastic constant of the support is eliminated. In one embodiment, a detection rod is support by leaf springs. Negative feedback control is utilized to return deformation of the leaf springs to zero at all times to eliminate the spring constant effect of the leaf springs. Since the average displacement of the leaf springs is zero, the positional relation between the permanent magnet and the coil forming the electromagnetic force generator varies negligibly.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: March 27, 2001
    Assignee: Seiko Instruments Inc.
    Inventors: Nobutaka Nakamura, Haruo Takeda, Masafumi Take
  • Patent number: 6176139
    Abstract: A pressure force sensor has two oppositely located connectors for a force introduction to an inside located force sensor module which emits an output signal as a function of an external pressure force, a fork arm attached to each of the connectors and having two fork ends which are offset by 90° and enclose the force sensor module, and pressure elements located between respective bases of the fork arms and a force introduction surface of the force sensor module, the pressure elements being also laterally enclosed by angled sections of the fork ends, so that pressure forces as well as tensile forces can be passed from the connectors to the force introduction surface of the force sensor module.
    Type: Grant
    Filed: January 16, 1999
    Date of Patent: January 23, 2001
    Assignee: Robert Bosch GmbH
    Inventors: Wolfgang Seils, Georg Blosch
  • Patent number: 6079278
    Abstract: Slackness of a ball spline joint which engages a first member of a circular shape and a second member fitted outside of the first member is measured by measuring a displacement of a first measurement point (P1) and a second measurement point (P2). The measurement points are set on the radial line passing through the center of the first member and the center of the spline groove. Using the distances (R1, R2) between the center of the first member and the measurement points (P1, P2), and the displacement amount (A1, A2) of the measurement points (P1, P2) under a predetermined relative torque, the slackness of the joint is calculated. By arranging the measurement points (P1, P2) on either side of the center of the first member, the effect of measurement error in the displacement amount (A1, A2) on the calculation is reduced.
    Type: Grant
    Filed: October 27, 1998
    Date of Patent: June 27, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Hideo Ishida
  • Patent number: 6055866
    Abstract: A method and apparatus or device are shown for checking the solidity of vertically anchored masts increasing tensile and compression forces which can be acquired with a force sensor are introduced into the mast above its anchoring, in order to load the mast with bending moments aligned oppositely to one another. With at least one distance sensor which can be brought to bear against the mast above the mast anchoring a lateral deflection of the mast which occurs on account of the bending moments is measured. The readings for the force F and the deflection S produced by the force and distance sensors are processed in an evaluation unit with respect to the functions f=F(S) and f=S(F), this being separately according to the courses of the functions f1 for the compression loading case f2 for the tensile loading case.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: May 2, 2000
    Inventors: Mathias Roch, Oliver Roch
  • Patent number: 6029504
    Abstract: A tube loading apparatus and method for tensile strength and leak testing an elongated, hollow tube such as a steam generator heat transfer tube of a steam generator plant. The apparatus may be used to determine the axial or compressive load placed on a hollow tube.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: February 29, 2000
    Assignee: ABB Combustion Engineering Nuclear Power, Inc.
    Inventors: Philip Edward House, Alan Brian Goulet
  • Patent number: 5950142
    Abstract: The tension in an optical fiber being drawn from a preform is monitored by sensing its motion transverse to the drawing direction and analysing the sensed motion using an autoregressive time-series model to provide a power spectrum. One of the peaks of the spectrum is identified as associated with the fundamental natural frequency of the drawn fiber and the frequency of that peak is used in a calculation of the tension of the fiber.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: September 7, 1999
    Assignee: Pirelli General plc
    Inventor: Hong Shi
  • Patent number: 5948994
    Abstract: A multi-functional test machine is provided.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: September 7, 1999
    Inventors: Ming-Hwa R. Jen, Wei-Hwang Lin
  • Patent number: 5798463
    Abstract: A tensile test fixture for applying constant tensile forces to a tensile test specimen comprises two mounting grips, each mounted to one of two lever arms in a pivoted lever arm frame structure. One end of each lever arm is pivotally attached to a compression column while the other end of each lever arm is attached to one end of a force-applying assembly. The mounting grips are pivotally attached to their respective lever arms between the compression column and the force-applying assembly and are designed to hold opposite ends of a tensile test specimen. The force-applying assembly comprises stress and strain modules that are interchangeably installable into the force-applying assembly to selectively subject tensile test specimens to constant strain and constant stress.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: August 25, 1998
    Assignees: Automotive Composites Consortium, University of Tulsa
    Inventors: John C. Doudican, Edward M. Hagerman, John M. Henshaw, Laura J. Meyer, Daniel Q. Houston
  • Patent number: 5767402
    Abstract: A material testing machine includes a support structure and a DC brushless linear motor operable to develop a force along a reaction axis. The DC brushless linear motor includes a set of magnets disposed along a line on the support structure parallel to the reaction axis. An elongated member slidably guided by the support structure on the reaction axis includes a plurality of coils proximate the set of magnets. A controller selectively energizes the coils.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: June 16, 1998
    Assignee: MTS Systems Corporation
    Inventors: Gary S. Sandlass, Larry G. Mosiman, Scott G. Johnson, Douglas S. Morrissette
  • Patent number: 5706698
    Abstract: A tester for measuring a durability of a knitted yarn portion in which at least two sets of yarns, including a set of first yarns and a set of second yarns, are intersected, the tester includes: a first holding unit holding ends of the two sets of yarns at first positions that are relative to the knitted yarn portion; a second holding unit holding opposite ends of the two sets of yarns at second positions that are relative to the knitted yarn portion; and a position adjusting unit, connected to the first holding unit and the second holding unit, allowing at least one of the first positions and the second positions, relative to the knitted yarn portion, to be moved to other positions, thus varying an intersecting angle of the yarns of the knitted yarn portion.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: January 13, 1998
    Assignees: Toyota Jidosha Kabushiki Kaisha, Toyoda Gosei Co., Ltd.
    Inventors: Kiyoshi Hanai, Kanji Ishii, Nobuaki Funahashi, Fumio Ikeda
  • Patent number: 4869112
    Abstract: A mechanical screw drive loading test frame has a crosshead on the frame with a grip supported from the crosshead, and a second grip for gripping a second end of a specimen on which a second grip is connected to an axially movable shaft which is ragidly supported and guided for axial movement for loading the specimen. The support for the second grip is in a second rigid cross member positioned very close to the second grip to prevent lateral loads from loading the specimen transversly. The loading shaft is loaded from below the rigid cross member by a screw through a coupling and mounting arrangement which isolates load caused by misalignment in the drive screw or drive motor from the movable shaft and second grip.
    Type: Grant
    Filed: November 8, 1988
    Date of Patent: September 26, 1989
    Assignee: MTS Systems Corporation
    Inventors: Martin M. Gram, Richard E. Bearden
  • Patent number: 4464937
    Abstract: An extensometer readout circuit conditions a strain information signal, representing strain of a specimen being tested, in such a way that yield point measurements and final elongation measurements of such specimen may be concurrently obtained. The strain information signal is provided by subjecting the specimen to a tensile or compression test by any conventional means known in the prior art. The strain information signal is first applied to a preamplifier. The preamplified strain information signal is then concurrently applied to both a high gain amplifier and a low gain amplifier. The signal obtained from the high gain amplifier is used for performing modulus calculations and for obtaining yield point measurements. The signal obtained from the low gain amplifier is used to obtain the total elongation measurement.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: August 14, 1984
    Assignee: MTS Systems Corporation
    Inventors: David E. Watts, Robert W. Winters
  • Patent number: 4227400
    Abstract: The length and firmness of a cigarette rod during smoking are measured on automatic basis to determine the effects of blend, moisture and temperature on the firmness of a cigarette rod behind the coal of a burning cigarette.
    Type: Grant
    Filed: May 29, 1979
    Date of Patent: October 14, 1980
    Assignee: Philip Morris Incorporated
    Inventors: John F. Nienow, Christopher L. Irving, Lynwood V. Shaw