Loose Object Detection Patents (Class 73/572)
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Patent number: 10351112Abstract: An apparatus for testing vehicle stone chippings is disclosed. The apparatus includes a stone chipping rig having a chassis. The chassis includes a first end, a second end, and a longitudinally extending tongue extending from the second end. A rolling fixture is coupled to the first end of the chassis. A stone chipping test device is coupled to the first end of the chassis adjacent to the rolling fixture for measuring an impact force of a stone that strikes the stone chipping test device. The apparatus further includes a pilot vehicle used to receive the stone chipping rig so as to measure the impact force of the stone launched off the pilot vehicle wheels when the pilot vehicle travels on a road with loose gravel. The stone chipping rig is defined as a test vehicle towed at a fixed distance behind the pilot vehicle.Type: GrantFiled: February 1, 2017Date of Patent: July 16, 2019Assignee: TOYOTA MOTOR ENGINEERING & MANUFACTURING NORTH AMERICA, INC.Inventor: Kevin C. Nevaux
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Patent number: 9261421Abstract: A fixing force measuring apparatus including a section for applying a predetermined controlled hammering force to a wedge surface to generate a hammering sound, a section for controlling the hammering sound generated, a section for obtaining plural kinds of feature quantities such as a feature quantity due to a hammering sound energy, and a feature quantity due to a frequency of the hammering sound from the hammering sound collected by an arithmetic operation, and a section for obtaining a fixing force corresponding to the plural kinds of feature quantities by using a correlative relationship between the wedge fixing force previously obtained, and the plural kinds of feature quantities.Type: GrantFiled: December 10, 2013Date of Patent: February 16, 2016Assignee: Mitsubishi Hitachi Power Systems, Ltd.Inventors: Yoshitaka Tsutsui, Nobuaki Nakasu, Keiji Suzuki, Kengo Iwashige, Mitsuru Onoda, Harumasa Tsuchiya, Yasuaki Kageyama
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Patent number: 8966983Abstract: The invention relates to a method and a device for the contactless detection of laminated, flat objects, particularly sheet-like recording media. There is a galvanic separation and mechanical decoupling between the transmitter and receiver to improve detection. These measures can be further improved with correction characteristic methods.Type: GrantFiled: July 26, 2012Date of Patent: March 3, 2015Assignee: Pepperl + Fuchs GmbHInventor: Dierk Schoen
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Publication number: 20140290366Abstract: An apparatus includes a cantilevered element including a coating material having an affinity for at least one compound. The apparatus further includes a first capacitive plate and a second capacitive plate that are each spaced from and capacitively coupled to the cantilevered element. The first capacitive plate is configured to induce a vibration in the cantilevered element at a frequency related to a mass of the cantilevered element. A frequency detector is coupled to the second capacitive plate to detect a change in vibrational frequency of the cantilevered element as a result of at least one particle of the at least one compound coupling to the coating material.Type: ApplicationFiled: June 12, 2014Publication date: October 2, 2014Inventor: Robert Raymond Miller, II
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Publication number: 20130160549Abstract: A system is provided in one embodiment for real-time detection of an object in a fluid without interfering with fluid flow. The system may include a sensor element coupled to a fluid passage, which can transmit energy substantially parallel to the flow direction of a fluid in the fluid passage and receive energy reflected from an incident object in the fluid. Reflected energy can also be analyzed as a function of object size and material such that an object can be classified or characterized through appropriate signal analysis. A method is provided in another embodiment for detecting an object in a fluid passage. The method may include transmitting ultrasonic energy through an interface membrane into the fluid and receiving ultrasonic energy reflected from the object. A pressure change in the reflected ultrasonic energy may be measured and converted to a signal for an output device.Type: ApplicationFiled: June 15, 2011Publication date: June 27, 2013Applicant: BELL HELICOPTER TEXTRON INC.Inventor: Jeffrey P. Nissen
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Patent number: 8266965Abstract: A method and a device for the contactless detection of laminated, flat objects, particularly sheet-like recording media. There is a galvanic separation and mechanical decoupling between the transmitter and receiver to improve detection. These measures can be further improved with correction characteristic methods.Type: GrantFiled: June 7, 2006Date of Patent: September 18, 2012Assignee: Pepperl + Fuchs GmbHInventor: Dierk Schoen
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Patent number: 7854167Abstract: A diagnosis device for diagnosing loosening of a stator core of a rotary electrical machine. The diagnosis device has: excitation means for vibrating the stator core in the radial direction; vibration detection means for detecting the vibration of the stator core in the radial direction; means for frequency-analyzing an output signal of the vibration detection means that detects vibration generated in the stator core when the stator core is vibrated by the excitation means so as to extract a measurement natural vibration mode of the stator core in a circular ring natural vibration mode; means for estimating a circular ring natural vibration mode of the stator core from shape data of the stator core; and means for determining a clamping state of the stator core by comparing the measurement natural vibration mode and a determination criterion obtained based on the estimated natural vibration mode.Type: GrantFiled: May 16, 2008Date of Patent: December 21, 2010Assignee: Kabushiki Kaisha ToshibaInventors: Yutaka Hashiba, Norio Takahashi, Masayuki Ichimonji, Hitoshi Katayama, Takaharu Tani, Tatsuo Taniguchi, Masayuki Takahashi
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Publication number: 20080282803Abstract: A diagnosis device for diagnosing loosening of a stator core of a rotary electrical machine. The diagnosis device has: excitation means for vibrating the stator core in the radial direction; vibration detection means for detecting the vibration of the stator core in the radial direction; means for frequency-analyzing an output signal of the vibration detection means that detects vibration generated in the stator core when the stator core is vibrated by the excitation means so as to extract a measurement natural vibration mode of the stator core in a circular ring natural vibration mode; means for estimating a circular ring natural vibration mode of the stator core from shape data of the stator core; and means for determining a clamping state of the stator core by comparing the measurement natural vibration mode and a determination criterion obtained based on the estimated natural vibration mode.Type: ApplicationFiled: May 16, 2008Publication date: November 20, 2008Applicant: Kabushiki Kaisha ToshibaInventors: Yutaka Hashiba, Norio Takahashi, Masayuki Ichimonji, Hitoshi Katayama, Takaharu Tani, Tatsuo Taniguchi, Masayuki Takahashi
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Publication number: 20080034869Abstract: The invention relates to a method and device for imaged representation of acoustic objects by taking acoustic cards with the aid of an acoustic set to which a reference image of a measure object is associated. Said invention also relates to an information program product and to a recording support which is readable by a corresponding computer and can be used, in particular for photographic and filmic documentation and for acoustic analysis of noise sources, for example of machines, devices and vehicles. For this purpose an acoustic camera is used. Said camera consists of a microphone assembly of an integrated video camera, a data recording unit connected to a microphone and to an angular sensor, a calibration device and a computer.Type: ApplicationFiled: January 30, 2004Publication date: February 14, 2008Inventors: Gerd Heinz, Dirk Dobler, Swen Tilgner
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Patent number: 6993854Abstract: A centrifugal dryer of the present invention includes: a chamber for performing drying processing for plural substrates; a cradle, installed inside chamber, and drying plural substrates by rotation driving in a state of being held therein; and an elastic wave sensor for detecting an elastic wave generating upon striking of a chip from plural substrates to said chamber during the processing therefor.Type: GrantFiled: April 25, 2002Date of Patent: February 7, 2006Assignees: Renesas Technology Corp., Mitsubishi Electric Engineering Company LimitedInventors: Hirotoshi Ise, Toshiki Oono, Tatsuo Mizuno
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Publication number: 20040112136Abstract: Described herein is a technology for facilitating diagnosis of the operation of devices or machines based, at least in part, upon the acoustics of such.Type: ApplicationFiled: December 11, 2002Publication date: June 17, 2004Inventors: James P. Terry, William W. Uhl
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Patent number: 6558278Abstract: A method of determining the frequencies of a golf club entails suspending the golf club in a substantial free state and thereafter striking or engaging the golf club to cause the same to vibrate or oscillate. Once the golf club has been excited, the method entails measuring the natural frequencies of the golf club. More particularly, in the substantial free state, the club is suspended by a flexible connector which is secured to the grip end of the club.Type: GrantFiled: December 9, 2000Date of Patent: May 6, 2003Inventors: Julian W. Bunn, III, Alfred L. Wicks
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Patent number: 6499002Abstract: A method and system for generating a noise index for a mechanical system in which noise data is acquired over a predetermined frequency range. A fundamental harmonic frequency is chosen and this fundamental harmonic frequency is used to mark harmonic and sub-harmonic data bins. The amplitude of the harmonic and sub-harmonic data bins are recorded and a plurality of sub-harmonic bins equally offset from the center of each harmonic frequency are averaged and the average is subtracted from the preceding harmonic level. The result is accumulated as harmonic content levels to generate a harmonic index number.Type: GrantFiled: January 31, 2000Date of Patent: December 24, 2002Assignee: General Electric CompanyInventor: William E. Lancaster
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Patent number: 6289724Abstract: A method and apparatus for examining internal components of a sealed container is disclosed. In one embodiment, the method includes the steps of attaching an acoustic sensor to an outer surface of the sealed container and moving the sealed container about at least one axis of the sealed container. An audio signal is received from the acoustic sensor, where the audio signal is generated by a component within the sealed container that is put into motion as a result of the step of moving the sealed container about the at least one axis. The audio signal is analyzed to determine the frequency of the signal. In an embodiment for an apparatus of the present invention, an acoustic sensor is attached to the sealed container. An amplifier is coupled to the acoustic sensor and receives an audio signal from the acoustic sensor. The audio signal is generated by a component within the sealed container that is put into motion as a result of movement of the sealed container.Type: GrantFiled: August 5, 1999Date of Patent: September 18, 2001Assignee: TyCom (US) Inc.Inventors: Ramesh Varma, J. Bradley Hunter, Marty Alexander
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Patent number: 5754497Abstract: A method for locating structure-borne sound events in pressure enclosures to be monitored in power plants, includes positioning sensors at various locations on a pressure enclosure. Signals are picked up with each of the sensors upon arrival of a sound wave generated by a structure-borne sound event and propagating along the pressure enclosure. The signals are stored in recording devices disposed downstream. A location of the structure-borne sound event is determined with a hyperbolic section method, from transit time differences resulting from different arrival times of the sound wave at two different sensors. Each range of possible speed values for the propagation of the generated sound wave is made a basis of one respective structure-borne sound event. The hyperbolic section method is performed separately for each speed value of the range for outputting a location indication with an error. The location with the least error is selected as the most likely location of the structure-borne sound event.Type: GrantFiled: January 27, 1997Date of Patent: May 19, 1998Assignee: Siemens AktiengesellschaftInventor: Carlos Tapia-Egoavil
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Patent number: 5515726Abstract: A vehicle wheel cover noise testing machine comprises a test wheel mounted for rotation in the compartment of a first housing. A wheel cover is attached to the test wheel. A drive wheel is mounted in the compartment of a second housing. The housings are supported adjacent to one another in a cage and have adjacent walls provided with registering openings. The drive wheel is in frictional peripheral contact with a tire on the test wheel through the openings so that the test wheel may be rotated by the drive wheel. A microphone in the compartment for the test wheel detects wheel cover noise.Type: GrantFiled: December 27, 1994Date of Patent: May 14, 1996Assignee: Chrysler CorporationInventor: Timothy R. Welsh
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Patent number: 5245875Abstract: The process consists in subjecting the component to vibrations and detecting disturbances in the vibrations. The device for the application of this process comprises a vibrator (21) equipped with a swivelling clip (22) in which the component to be tested (23) is fixed. An accelerometer (34) fixed to the vibrating support (30) of the clip delivers an output signal to an electronic circuit which suppresses the low frequencies and which controls indicator lights indicating the acceptance or the refusal of the component. The position of the clip can be modified during the check.Type: GrantFiled: August 16, 1991Date of Patent: September 21, 1993Assignee: Societe de Fabrication Maty SarlInventor: Alain Tyrode
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Patent number: 5090244Abstract: System for detecting free particles in component housings assembled on a printed-circuit card, according to which the card is made integral with a vibrating frame by a pneumatic mechanism. A removable piezo-acoustic sensor makes it possible to test for the presence of free particles in one or more of the component housings.Type: GrantFiled: January 31, 1990Date of Patent: February 25, 1992Assignees: Thomson-CSF, Le Centre National d'Etudes SpatialesInventors: Daniel Potier, Jean Gruau, Albert Lecrivain
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Patent number: 5024090Abstract: A loose rock detector comprises an impact tool for hitting the rock face, sensors for detecting acoustic, rock motion and/or impact force signals generated by movement of the impact tool against the face of the rock, a data processor responsive to the sensors for correlating the above signals in the time and/or frequency domain against predetermined relationships to detect loose rocks and to assess mass and degree of looseness of the rock, and a display unit for displaying the results of the correlation.Type: GrantFiled: September 15, 1989Date of Patent: June 18, 1991Assignee: HDRK Mining Research LimitedInventors: Michel J. Pettigrew, David B. Rhodes, Eric G. Lux, Victor A. Mason
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Patent number: 4901572Abstract: A wedge measuring apparatus comprising a measuring head, capable of being inserted between a stator and a rotor of a revolving electric machine, for testing a coil-urging state of wedges inserted in a slot, and a mechanism for moving the measuring head in the longitudinal direction of the stator and the circumferential direction of the rotor. A test for the coil-urging state is performed to prevent a coil from extending from an opening in the radial direction. In this case, the coil is inserted in a slot having the opening formed in a stator wall surface opposite to the rotor, and the slots are formed along the axial direction of the stator core.Type: GrantFiled: February 17, 1989Date of Patent: February 20, 1990Assignee: Kabushiki Kaisha ToshibaInventor: Toshimitsu Suyama
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Patent number: 4897823Abstract: A method for the location of shocks with a structure-borne sound monitoring system is used especially for pressurized enclosures in power plants, particularly nuclear power plants. Structure-borne sound monitoring systems were heretofore dependent upon assumptions regarding the propagation velocities of the structure-borne sound sensors. According to the invention an exact method of ascertaining the propagation velocities and the burst location is given. The invention begins with the realization that the frequency spectrum of the respective bursts of information for clarification of the dispersion behavior, for identifying the sound wave modes and for deriving the group velocity of these modes is self-evident. Burst signal-rise time differences, wave modes, especially s.sub.0 and a.sub.0 mode, as well as the pertaining group velocities are then ascertained.Type: GrantFiled: February 1, 1988Date of Patent: January 30, 1990Assignee: Siements AktiengesellschaftInventor: Konrad Krien
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Patent number: 4862746Abstract: A vibration tester for measuring the looseness of thread connections is disclosed which comprises a support frame, a specimen holding section mounted in the support frame and a pair of pneumatic hammers mounted at both ends of the specimen holding section. The specimen holding section consists of a largely cylindrical shaped hollow holder, a strain gauge provided and attached to the gauge carrier for measuring the looseness of specimens, a vibrating plate mounted on the hollow holder in contact with the pneumatic hammers in such a manner as to be subjected to blows from the pneumatic hammers, and a guide mechanism adapted to guide the direction of pneumatic hammer blows. With this arrangement, the pneumatic hammers are activated to deliver impacts to the vibrating plates, with the bolt making up the specimen set on the tester by being inserted through the gauge carrier, hollow holder and vibratory plate, with the nut tightened to the protruding end of the bolt.Type: GrantFiled: March 16, 1987Date of Patent: September 5, 1989Inventor: Minoru Komatsu
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Patent number: 4854171Abstract: The presence of extraneous materials such as polypropylene strings or strands in textile fiber material is detected at the bale shaver or plucker in which tufts of the textile fiber are removed from the bale by a rotary plucker head. The plucker head is received in a suction removal hood so that a strand which tends to be wound on the head will impact upon the hood and the frequency of such impact is automatically detected and, if found to be related to the frequency of rotation of the head, automatically causes shut down of the machine to enable clearing of the extraneous fiber or string from the head.Type: GrantFiled: March 4, 1988Date of Patent: August 8, 1989Inventor: Hubert Hergeth
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Patent number: 4850225Abstract: Measuring vibrational frequency of a pin attached at one end by collimating two laser beams onto the pin and back scattering the beams. The back scattered frequency is modulated by doppler effect and is heterodyned with the original beam frequency to produce a signal representative of each modulating frequency. The representative signals are summed together and also subtracted from one another. The summed and subtracted signals are representative, one of the vibrational frequency of the pin and the other of the degree of focussing accuracy of each laser beam onto the pin.Type: GrantFiled: October 31, 1988Date of Patent: July 25, 1989Assignee: Northern Telecom LimitedInventors: Wayne G. Chen, Newman K. Lin
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Patent number: 4805457Abstract: In the test of a casing enclosed shaft and impeller for structural integrity against defects such as loose bolts or cracks, an apparatus and process is disclosed which enables in-situ testing to occur within a casing. A model of the shaft and impeller, such as a spare part, is suspended so as to simulate the in casing boundary conditions and is then vibrated. Vibration or "ringing" occurs through a normally exposed end of the shaft far removed from suspected defects. A cap can be used to suspend the shaft and impeller or rotor. Vibration is imparted to the remote end of the shaft, sometimes on the cap, with an instrumented hammer blow of specific duration and known energy. Measurement and resolution of the resultant vibrations and energy dissipating damping occurs by mounting accelerometers to the remote normally exposed shaft end and recording and playing back the vibrations from the mounted accelerometers through a spectrum analyzer.Type: GrantFiled: May 28, 1987Date of Patent: February 21, 1989Assignee: General Electric CompanyInventors: James H. Oates, Lun K. Liu, Swaminathan H. Sundaram, Hassanali Tafarrodi
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Patent number: 4770046Abstract: A method system for assessing the safety of a rotor of a shrinkage fitted type wherein an opening displacement of a crack is determined an elastic-plastic fracture method and a reduction in shrinkage fitting force is calculated based on the crack opening displacement. The safety of the rotor is assessed based on the reduction in shrinkage fitting force caused to occur by the opening of the crack.Type: GrantFiled: October 23, 1986Date of Patent: September 13, 1988Assignee: Hitachi, Ltd.Inventors: Satoshi Kanno, Shinji Sakata, Tasuku Shimizu, Ryoichi Kaneko, Kiyoshi Shimomura, Naoaki Shibashita
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Patent number: 4700127Abstract: A microwave probe has a cylindrical support made of stabilized zirconia being excellent in heat insulation, and the cylindrical support is threadably installed at a partitioning wall to partition an atmosphere of high temperature. The support is provided at the center with a through hole, and an antenna for transmitting or receiving microwave is installed at one opening of the through hole positioning at outside of the partitioning wall, and a metal ring member is installed at other opening of the through hole positioning within the partitioning wall. The transmitting and receiving antenna and the ring member are fixed to respective openings by a ceramic adhesive which is filled in the through hole and excellent in heat insulation. A part of the ring member projects in the atmosphere.Type: GrantFiled: May 1, 1985Date of Patent: October 13, 1987Assignee: Nippon Soken, Inc.Inventors: Kunihiko Sasaki, Masao Kodera, Seizi Huzino, Takeshi Tanaka
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Patent number: 4641526Abstract: Method and apparatus for estimating the location of an unknown sound source in a structure to be monitored, wherein sounds from at least three known sound sources are detected by a plurality of detectors. At least one of peak value data and signal arrival time data derived from the outputs of the detectors are classified for each of the known sound sources and stored in a storage. Pattern differences from each of the known sound sources to a number of predetermined positions respectively, are calculated to prepare for each of the known sound sources a correspondence table indicating relationships between the calculated pattern difference and the real distances from the known sound source positions to the predetermined positions, the correspondence table being stored in a storage. The pattern differences for each of the known sound source positions are calculated on the basis of the sound signal data derived through detection of a sound from an unknown sound source and the data stored in the storage.Type: GrantFiled: June 5, 1984Date of Patent: February 10, 1987Assignee: Hitachi, Ltd.Inventors: Shigeru Izumi, Makoto Senoh, Koji Tsumaki, Kenji Miyata
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Patent number: 4605924Abstract: Acoustic waves are sensed in contact with or near the plant at at least two points (1, 2, 3, 4) whose position is accurately determined with respect to the monitored region. The order of arrival of the acoustic waves at the sensing points (1, 2, 3, 4) is determined and this order is compared with a predetermined order corresponding to a phenomenon occurring in the monitored region. An alarm is triggered if the order of arrival corresponds to the predetermined order. The apparatus includes an encoding logic (9), a comparator (10) and a monostable circuit (12) triggering the alarm. The invention is particularly applicable to monitoring nuclear reactors in operation.Type: GrantFiled: February 1, 1984Date of Patent: August 12, 1986Assignee: Framatome & CIEInventors: Jean Marini, Bernard Audenard
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Patent number: 4586378Abstract: Method and apparatus for evaluating location of an unknown sound generated in a structure such as a pressure vessel. A plurality of sound detectors are mounted on the structure for detecting sounds generated in the structure. On the basis of sound information of the unknown sound source derived from the outputs of the detectors, the location where the unknown sound is produced is determined. To this end, reference sounds are first generated at a plurality of known reference sound source positions, wherein information of the reference sounds derived from the outputs of the detectors are stored in a storage unit. Equi-pattern-distance curves each of which is in an equal pattern distance between a supposed unknown sound source and each of the reference sound sources are calculated on the basis of the reference sound information. The equi-pattern-distance curves are further corrected in accordance with the reference sound information.Type: GrantFiled: October 5, 1984Date of Patent: May 6, 1986Assignee: Hitachi, Ltd.Inventors: Shigeru Izumi, Yoshihiro Michiguchi, Makoto Senoh
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Patent number: 4422320Abstract: A device for determining the tightness of a wedge used to close the slot of a dynamoelectric machine and firmly restrain the conductors installed in the slot, is in the form of a tapping hammer or similar tapping tool. The heat of the hammer contains an accelerometer which outputs a pulse signal having a duration representing the time the head is in contact with the wedge. The pulse signal duration is also related to the tightness of the wedge. Associated electronic circuitry measures the time duration and displays the measured value on a digital display on the hammer unless this display is inhibited. The strength of each blow is assessed by an integrating circuit which gives an output related to the strength of the blow. If this output is not within predetermined upper and lower limits, defining a "window", the display of the measured time duration is inhibited and instead the display indicates that the blow was too hard or too weak.Type: GrantFiled: February 1, 1982Date of Patent: December 27, 1983Assignee: Canadian General Electric Company LimitedInventors: Donald G. Moorby, Graham T. McMillen, Ralph S. Flemons
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Patent number: 4392214Abstract: Sound monitoring device for an industrial installation to detect possible impacts of stray bodies including at least one set of two sound detectors arranged in contact with the wall of the installation or in its vicinity, and a measuring and alarm circuit. The detectors are connected to this measuring circuit which includes a device for measuring the separation in time between the reception of the sound waves at one and the other detector, a comparator for this separation with at least one set of two predetermined values, and an alarm which is triggered if the separation in time falls between the two predetermined values. The invention is particularly useful for surveillance of the primary circuit of a pressurized water nuclear reactor.Type: GrantFiled: February 17, 1981Date of Patent: July 5, 1983Assignee: FramatomeInventors: Jean Marini, Bernard Audenard
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Patent number: 4285241Abstract: The impact signal derived from an acoustic transducer has a unique signature represented by its frequency spectrum. The present invention generates under predetermined conditions with objects, each of definite weight and form, a series of impact signals for reference purposes and correlates an actual impact signal from an unknown impacting object with such reference impact signals by comparing the frequency spectra, thereby to indirectly recognize the impacting object.Type: GrantFiled: July 13, 1979Date of Patent: August 25, 1981Assignee: Westinghouse Electric Corp.Inventors: John R. Smith, William Ciaramitaro, Raj Gopal
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Patent number: 4231258Abstract: In a method for detecting foreign matters present in gas sealed electrical apparatus including a tank at the ground potential and containing an insulating gas and a high voltage live part disposed in the tank, a voltage is applied to the high voltage live part causing generation of ultrasonic waves and the ultrasonic waves propagated through the tank is sensed by a sensing element mounted on the tank.Type: GrantFiled: January 2, 1979Date of Patent: November 4, 1980Assignees: Tokyo Shibaura Denki Kabushiki Kaisha, Tokyo Denryoku Kabushiki KaishaInventors: Shinichi Menju, Kunio Takahashi, Eiichi Haginomori, Yoichi Murakami, Eiichi Zaima
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Patent number: 4184372Abstract: A particle detection system for detecting the presence of a particle within a sealed enclosure. It includes a vibrator or shaker whereon is mounted an electromechanical shocking apparatus whereby an operator-actuated switch causes an armature to provide a physical or mechanical shock to the enclosure. A transducer is employed to sense the noise created by a particle within the enclosure striking a side wall thereof, and suitable indicating means are connected in circuit with such transducer to afford visual and audible indications of the presence of the particle. Means is provided for muting the indicators whenever the enclosure is shocked by the armature to prevent the indicators from responding to the noise created by such shocking.Type: GrantFiled: October 31, 1977Date of Patent: January 22, 1980Assignee: B and W Engineering ServicesInventor: Jack M. Brown