Patents Assigned to Sigma Instruments Inc.
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Patent number: 6539328Abstract: A device and process for measurement and treatment of spinal mobility is disclosed. The device includes an impulse and sensing head capable of determining spinal segment mobility by applying a force impulse to a spinal segment and generating a waveform characteristic of spinal mobility. An inclinometer disposed within the head determines the angle of incidence of the head in contact with the spinal segment in at least one, preferably three, axis. Characteristics of the waveform and the angle of incidence are analyzed to determine spinal mobility. The information in the waveform and device are then used to treat the patient by applying an oscillating head to a spinal segment so that spinal mobility is increased.Type: GrantFiled: April 30, 1999Date of Patent: March 25, 2003Assignee: Sigma Instruments, Inc.Inventors: Joseph G. Cremonese, Tamas Becse, John B. Crunick, Lou L. Laskey, Jr.
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Patent number: 5136456Abstract: The disclosed faulted current indicator ignores temporary overloads and transients by inhibiting any trip resulting from an overcurrent signal until a disabling circuit senses that a fuse or circuit breaker has reduced the line current to zero.Type: GrantFiled: November 17, 1989Date of Patent: August 4, 1992Assignee: Sigma Instruments, Inc.Inventor: Thomas Yeh
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Patent number: 5124642Abstract: A power line post insulator has a housing that encloses two inductive sensors that transversely straddle a recess which receives the power conductor. Wires connect the sensors additively with respect to voltages induced by currents in the conductor between the sensors. The sensors may each include one or two additively connected coils.Type: GrantFiled: December 21, 1989Date of Patent: June 23, 1992Assignee: Sigma Instruments, Inc.Inventor: Thomas I. Marx
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Patent number: 5111189Abstract: In the disclosed fault indicator a sensing device is arranged for location in the magnetic field surrounding a conductor, an electronic device responsive to the sensing device assumes a first state in response to the sensing device sensing a trip condition and remains in the first state until set to a second state, a signaling device coupled to the electronic device serves for generating a signal only in response to the electronic device being in the first state, and a timing device responsive to the electronic device assumes the first state serves for setting the electronic device to the second state after a predetermined period. The sensing device is an inductive sensor, preferably a coil with an axis transverse to the conductor. In one embodiment an inrush restraint circuit renders the electronic device insensitive to inrush currents.Type: GrantFiled: November 27, 1989Date of Patent: May 5, 1992Assignee: Sigma Instruments, Inc.Inventor: Thomas Yeh
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Patent number: 5097202Abstract: In a sensor for sensing current in a conductor, a magnetic laminar arrangement adapted to surround the conductor passes through a coil. Inside the coil the laminar arrangement forms a gap with two projections extending transverse to lamina within the arrangement and facing each other. In one embodiment the coil drives a display to form part of a fault indicator.Type: GrantFiled: June 5, 1989Date of Patent: March 17, 1992Assignee: Sigma Instruments, Inc.Inventor: John G. Gamble
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Patent number: 5055771Abstract: A sensor in a faulted current indicator includes a coil and a magnetic arrangement passing through the coil and around a current-carrying conductor for coupling the coil to the conductor. The magnetic arrangement has given magnetic reluctance and forms a higher reluctance section, such as a gap, within the coil. Preferably the magnetic arrangement includes a U-shaped laminate and two core laminations joined to the U-shaped laminate by two gaps to allow for installation around the conductor. The ferromagnetic plate outside the coil shields the coil. The sensitivity of the sensor is increased by coating the inner surface of the U-shaped laminate and the core lamination surfaces contacting the U-shaped laminate with a high Ni content ferromagnetic material.Type: GrantFiled: August 21, 1989Date of Patent: October 8, 1991Assignee: Sigma Instruments, Inc.Inventors: John G. Gamble, Matthew G. Dillon
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Patent number: 5045778Abstract: An inrush restraint in a fault indicator disables trip in response to the current in the cable being monitored changing from reset to trip values within a predetermined period.Type: GrantFiled: January 30, 1989Date of Patent: September 3, 1991Assignee: Sigma Instruments, Inc.Inventors: Joseph R. Thibodeau, Matthew G. Dillon
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Patent number: 5029039Abstract: A fault indicator which senses current in a cable, resets in response to a minimum current and arms a trip arrangement in response to current rising a predetermined amount with respect to time. If the rising current also opens a circuit breaker within a predetermined time and cuts off current to the cable, the indicator trips. If no zero current occurs within the time period, the trip arrangement is disarmed for the next current rise.Type: GrantFiled: August 7, 1989Date of Patent: July 2, 1991Assignee: Sigma Instruments, Inc.Inventor: Thomas Yeh
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Patent number: 5003426Abstract: A faulted circuit indicator includes an inrush restraint circuit that suppresses a trip signal when an inrush current rises from below a minimum value to a trip value within a predetermined time and then drops again to another value such as the trip value. According to various aspects the restraint ends after a fixed time or after a variable time. According to another aspect a second trip circuit overrides the inrush restraint circuit when the current rises a given amount beyond the first trip value.Type: GrantFiled: June 30, 1989Date of Patent: March 26, 1991Assignee: Sigma Instruments, Inc.Inventors: Thomas Yeh, Joseph R. Thibodeau
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Patent number: 4984124Abstract: The disclosed faulted current indicator senses current in a line having a breaker or fuse, and avoids tripping in response to current inrush signals by producing a trip signal in response to an overcurrent occurring for an overcurrent duration which is inversely related to the magnitude of the overcurrent and is faster than the overcurrent operating time of the breaker or fuse. In one embodiment, this involves operating a current protection device in response to an overcurrent occurring for a second overcurrent duration inversely related to the magnitude of the overcurrent according to a first characteristic, and adjusting the first overcurrent duration to follow a second characteristic having variations substantially the same as the first characteristic but having a shorter first overcurrent duration than the second overcurrent duration.Type: GrantFiled: June 30, 1989Date of Patent: January 8, 1991Assignee: Sigma Instruments, Inc.Inventor: Thomas Yeh
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Patent number: 4980790Abstract: The reset circuit of a fault indicator is coupled to a transformer secondary winding by a cable having an elongated conductor and a resistance close to the secondary winding. The resistance is capable of withstanding a minimum transient impulse of 10 kv.Type: GrantFiled: January 17, 1989Date of Patent: December 25, 1990Assignee: Sigma Instruments, Inc.Inventor: Joseph R. Thibodeau
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Patent number: 4968884Abstract: In the disclosed outdoor lighting control, angular reflectors (52) direct vertical light passing through a translucent dome (38) onto a vertically oriented photocell (24) and a rigid vertically-adjustable sheet (54) between the photocell and the reflectors regulates the operating point of the photocell. The backs of the reflectors, and a socket (14) projecting vertically from a base (12) under the dome, shield the vertical photocell from horizontal light.Type: GrantFiled: April 11, 1989Date of Patent: November 6, 1990Assignee: Sigma Instruments Inc.Inventor: Thomas Yeh
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Patent number: 4864264Abstract: In the disclosed device, a pair of magnets supported in the ends of a C-shaped yoke bias an armature into one of the two rotary positions. A short pulse to a coil about the center of the yoke induces a short term magnetic field that supplements the polarity at one end of the yoke so as to either maintain the armature in its biased position or swing the armature to its other biased position. A subsequent pulse, producing a field in the opposite direction, returns the armature to its first position. In each case, the magnets retain the armature in its biased position even after the pulse stops. The armature pivots between portions of the yoke magnetized by the same magnet.Type: GrantFiled: January 20, 1988Date of Patent: September 5, 1989Assignee: Sigma Instruments, Inc.Inventor: John G. Gamble
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Patent number: 4859925Abstract: In a power distribution system, in order to maximize efficiency and to provide protection in the event of a lightning strike or other transient, a fiber optic drive is utilized to transmit measured parameter signals through a fiber optic link to a control system. The fiber optic drive is powered only in timed, short bursts at ten second to ten minute intervals with a power supply that capacitively draws small amounts of energy over the long intervals and energizes the drive with accumulated high power pulses.Type: GrantFiled: December 19, 1986Date of Patent: August 22, 1989Assignee: Sigma Instruments, Inc.Inventor: Thomas E. Beling
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Patent number: 4782287Abstract: In a watt-hour meter pulse width modulated signals, representing the voltage supplied to a load, serve as chopping signals that modulates a waveform representing current to produce an output indicative of power. A series of pulses is spaced on the basis of the power signal and the number of pulses connected as a measure of energy.Type: GrantFiled: October 30, 1986Date of Patent: November 1, 1988Assignee: Sigma Instruments, Inc.Inventor: Thomas I. Marx
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Patent number: 4763034Abstract: The electric motor includes a mover, which may be a rotor or actuator, and a stator having a number of poles projecting toward the mover. The poles have soft-magnetic teeth projecting toward the mover and extending transverse to the direction of mover movement, and the mover has soft-magnetic teeth projecting toward the stator teeth and extending transverse to the direction of mover movement. Windings energize the stator to move the mover. Dividing each pole transverse to the direction of mover movement to define two pole portions per pole, and locating permanent magnetic material between stator teeth in only one portion of each of the poles, enhances the motor torque while achieving a saving of permanent magnetic material. Preferably the magnetic material exists on alternate pole portions in successive poles.Type: GrantFiled: July 10, 1987Date of Patent: August 9, 1988Assignee: Sigma Instruments, Inc.Inventor: John G. Gamble
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Patent number: 4728830Abstract: Iron surfaces of stator poles, rotor periphery, or both stator poles and rotor periphery, of stepping motors are manufactured without teeth. The stepping effects of teeth are obtained by bonding, to the toothless surfaces, webs composed of fluted magnetic material having alternate thin and thick sections magnetized in the direction of the thickness of the material and carrying soft magnetic inserts in the flutes. The inserts form virtual teeth. The thick sections are magnetized in the direction opposite to the thin section and the flutes extend in the direction transverse to the direction of relative motion between rotor and stator.Type: GrantFiled: June 4, 1986Date of Patent: March 1, 1988Assignee: Sigma Instruments, Inc.Inventor: John G. Gamble
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Patent number: 4712028Abstract: A stepping motor with toothed stator poles and toothed rotor poles is magnetically enhanced by locating permanently magnetized inserts in the spaces between the stator teeth and magnetizing the inserts transverse to the direction of movement of the rotor and substantially transverse to the direction in which the teeth extend. In a hybrid motor with a split and axially magnetized rotor the inserts are magnetized to oppose the magnetization of the rotor. In a variable reluctance motor with an unmagnetized rotor inserts are placed in both rotor and stator and magnetized to aid each other. Linear motors use either configuration.Type: GrantFiled: May 21, 1984Date of Patent: December 8, 1987Assignee: Sigma Instruments, Inc.Inventor: Ralph W. Horber
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Patent number: 4700123Abstract: In a power distribution system, power line insulators have three electrodes, two of which are connected to the line and to ground, and the third of which forms a capacitively stepped down voltage corresponding to the line voltage, and use sensing coils to measure current. The sensing coils are inversely connected and differentially located to suppress noise.Type: GrantFiled: September 17, 1985Date of Patent: October 13, 1987Assignee: Sigma Instruments, Inc.Inventor: Thomas E. Beling
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Patent number: D530019Type: GrantFiled: February 23, 2004Date of Patent: October 10, 2006Assignees: MyPleasure/Sawhorse Enterprises, Sigma Instruments, Inc.Inventors: John Crunick, Sandor Gardos