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Hair Cutting Appliance

A haircutting appliance comprises an enclosed housing having a hollow handle connecting the housing to a vacuum source to carry away cut hairs from a subject's head.

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Class 324/254 - Second harmonic type


Subclass of Class 324 - Electricity: measuring and testing
Definition: Subject matter wherein the electrical coil sensing the change
No. of patents: 37
Last issue date: 04/29/2008


NumberTitleIssue Date
7366619Signal-processing unit for fluxgate magnetometers
A signal processing unit includes an integrating unit. The integrating unit is composed of a plurality of digital elements and is operative to integrate a detection signal over every quarter of one cycle of the detection signal to generate an integration value. The ...
04/29/2008
7353614Vehicle compass system with continuous automatic calibration
The compass system of the present invention utilizes an improved calibration routine in which a processing circuit of the compass recalibrates the compass each time three data points are obtained from a magnetic field sensor that meet predetermined criteria. One suc...
04/08/2008
7141968Integrated sensor system for measuring electric and/or magnetic field vector components
A compact sensor system integrates electric and/or magnetic field sensors to accurately measure, with a high level of sensitivity, one or more electric and magnetic vector components of fields. The electric and magnetic field data can be utilized separately or combi...
11/28/2006
7124656Gimbal mechanism
Provided is a gimbal mechanism comprising a support stand, an outer frame and an inner frame. The support stand includes a spaced pair of L-shaped legs comprising a first member having at least one first slot formed therethrough. The outer frame is nested within the...
10/24/2006
7123005Magnetometer with structure asymmetry correction
A differential magnetometer consisting of at least one active coil (4, 5) and a receiver coil (10) for which the windings are installed differentially, is provided with a measurement circuit (14) with a slaving device that corrects dissymmetry a...
10/17/2006
7098657Method of stabilising a magnetometer signal, and stabilised magnetometers
The magnetometer includes a magnetic core (1) with at least one branch (2, 3), at least one exciting coil (4, 5) and one take-up coil (10) sensitive to ambient fields thanks to the excitation field (B). An additional magnetic field, to ad...
08/29/2006
7098658Digital signal conditioning solution for a magnetometer circuit
A fluxgate magnetometer including a fluxgate and a digital processor. The digital processor includes an analog to digital converter for digitizing the back EMF from the fluxgate and a signal generator to generate the fluxgate driving signal. Further, a current sourc...
08/29/2006
6909368Magnetic field detection device
The present invention is a magnetic field detection device that makes use of a frequency characteristic affording circuit in order to selectively detect magnetic signals from a frequency domain accurately at a high level of sensitivity. The present invention has a m...
06/21/2005
6345228Road vehicle sensing apparatus and signal processing apparatus therefor
A road vehicle sensor provides an output signal having a magnitude which varies with time through a plurality of values as a vehicle passes the sensor. Signal processing apparatus monitors the timing of sensor signals generated from sensors in adjacent la...
02/05/2002
5973501Current and voltage probe for measuring harmonic distortion
A non-contact probe provides information as to relative amplitudes of harmonics of a current or voltage waveform as well as total harmonic distortion. The probe includes a non-contact sensor with an amplifier coupled thereto. Output signals from the ampli...
10/26/1999
5844814Optical position sensing device and method for sub-micron measurement
A high resolution, independent position sensor is provided, having application in a magnetic tape drive and other environments in which a linear or angular position is to be monitored. Analog outputs from an inexpensive, low resolution optical encoder are...
12/01/1998
5696575Digital flux gate magnetometer
Digital logic and a high resolution digital to analog converter are used to adequately digitize a magnetic signal that is subsequently processed by magnetic data processing algorithms. The high resolution digital to analog converter is directly incorporat...
12/09/1997
5652512Advanced digital flux gate magnetometer
Digital logic comprising a high speed analog to digital converter, a high speed analog to digital converter, a digital multiplier, and an infinite impulse response filter and decimation circuit are used to digitize a magnetic signal that is subsequently p...
07/29/1997
5530349Magnetic field sensor device using a flux-gate principle
The sensor device uses the flux-gate principle and detects and cancels a second harmonic frequency (2fo) output by a sensor coil (23). The sensor device includes a master oscillator (1) that provides a stable output that is supplied to a genera...
06/25/1996
5168223High sensitivity saturable core magnetic field sensor with symmetrical structure
A high sensitivity magnetic field sensor comprises a high permeability magnetic circuit (10) and excitation means (Le) for periodically saturating the magnetic circuit. Two identical windings (L1, L2) are symmetrically wou...
12/01/1992
5052116Method and apparatus for measuring azimuth
A method of measuring an azimuth by detecting the earth's magnetism by using two perpendicular coils to detect the azimuth according to the outputs of the coils, including the steps of converting the outputs of the coils by multiplying them by a constant ...
10/01/1991
4995165Roll-independent magneto meter system
A roll-independent magnetometer which may be used for example in a towed array magnetometer system comprises a first magnetic field sensor having iso-angular flux sensitivity about a roll axis and a second magnetic field sensor having sensitivity along th...
02/26/1991
4977374Radiation hardened magnetic voltage and/or current reference produced by a saturable, two core transformer with first harmonic nulling
A highly accurate, predictable and stable magnetic voltage and/or current reference that is substantially impervious to potentially hazardous radiation including neutrons, single or multiple particles, ionizing doses, particle beams and the like. The magn...
12/11/1990
4918824Electronic digital compass
An electronic digital compass utilizes an amorphous magnetostrictive wire 100 exhibiting reentrant behavior as a core. A sense wiring 104 is wrapped about the core and the core is driven with a triangular wave through a drive coil 102. The earth's magneti...
04/24/1990
4751783Azimuth determination apparatus
Disclosed is an azimuth determination apparatus attached to a motor vehicle for determinating the forward direction of the vehicle. The azimuth determination apparatus includes an azimuth sensor for generating orthogonal first and second signals indicativ...
06/21/1988
4717873Magnetic displacement transducer system having a magnet that is movable in a tube whose interior is exposed to a fluid and having at least one magnetometer outside the tube
A magnetic displacement transducer system for measuring the movement of a member includes an elongated permanent magnet which is mechanically coupled to the member so that the magnet moves parallel to its axis. A magnet-position sensor assembly, which inc...
01/05/1988
4692703Magnetic field sensor having a Hall effect device with overlapping flux concentrators
An alternating magnetic excitation field is generated in the flux concentrators (11,12) of a Hall effect device, including a Hall element (13), by passing an a.c. current through a coil (14). This alternating field serves to drive the flux concentrators i...
09/08/1987
4677381Flux-gate sensor electrical drive method and circuit
An electrical drive dircuit for a flux-gate magnetic sensor used in a digital compass for a vehicle provides signals for application to the primary of a flux-gate sensor to assure the core is saturated at a predetermined time during each cycle of the driv...
06/30/1987
4646011Electronic angular position transmitter with toroidal core and rotatable magnet
In a contact-less electronic angular-position transmitter having a turnable magnet (5), sensor coils (11, 12) arranged at right angles to each other are provided on a toroidal core (9), common to all sensor coils, of a magnetic-field detector formed in ac...
02/24/1987
4527123Improved method and apparatus for detecting and locating residually magnetized items
Methods and apparatus for detecting and locating residually magnetized misplaced tools and the like are disclosed. A sensitive gradiometer having a hand-held probe provides a balanced, phase cancelling magnetic field. The presence of a weak residual mange...
07/02/1985
4475078System for reading magnetic sensors for fault location in gas-insulated electrical apparatus
A fault location system for use with sealed, gas-insulated electrical power apparatus. The system includes a sensor for placement in close proximity to the outer surface of a housing of the apparatus and a detector for in-place reading of the sensor. The ...
10/02/1984
4399615Direction indicator
In a direction indicator including a direction sensor having an excitation coil wound on a core and two output coils wound thereon to cross at the right angles with each other, a direct current of given amount is supplied to the two output coils and a dir...
08/23/1983
4293815Fluxgate magnetometer circuit with earth's field elimination
A flux gate magnetometer system utilizes three independent flux gates for measuring the three mutually orthogonal components of the earth's magnetic field. A sensor for each flux gate includes a ring core with a toroidal winding as the drive winding and a...
10/06/1981
4277751Low-power magnetometer circuit with constant current drive
The drive signal applied to the drive winding of a magnetometer is provided by a voltage controlled oscillator. The average current flowing through the drive winding is monitored, and a signal representative of the average current is applied to the input ...
07/07/1981
4274052Current meter using core saturation
It is known for current meters to operate by sensing the magnetic field produced by the unknown current being measured. Such meters may include a core (200-1) of magnetic material which may be opened to receive a current carrying conductor (400-1) and whi...
06/16/1981
4110689Magnetic detecting apparatus with novel means for positioning sensor assembly in a housing
A magnetic locator in which flux-gate sensors are mounted in longitudinal notches at the ends of a tubular support to form an assembly which is inserted into a tubular housing, the sensors being press-fitted into the notches and the tubular support being ...
08/29/1978
4100492Harmonic magnetic field probe with novel core construction
The elongated core of a magnetic field probe is constructed of a heat-resistant diamagnetic body with lengthwise openings into which are received closely fitting wires of a magnetizable material. The wires are secured to the body by a heat-resistant cemen...
07/11/1978
4064834Apparatus for sensing the concentration of toner in a developer mix
An apparatus and method for sensing and controlling the concentration of toner in a developer mix comprising toner and carrier particles used to develop electrostatic images on a photoconductive or the like member includes the provision of a surface which...
12/27/1977
3983475Frequency selective detecting system for detecting alternating magnetic fields
A system for detecting an AC magnetic field of a desired frequency using a magnetic sensing element of the parametrically excited second harmonic oscillator, in which a reference signal having a repetition period substantially equal to the repetition peri...
09/28/1976
3982179Magnetic gradient detector with means for adjusting the parallelism of the sensors
The magnetic gradient detector has two magnetic field sensors with their magnetic axes arranged parallel to an imaginary line. The sensor electrical outputs are connected with one another such that an electrical signal is created corresponding to the grad...
09/21/1976
3971981Magnetism detecting system
A magnetism detecting system, in which reference magnetic fields sequentially scan many radial scanning lines obtained by dividing a plane to be detected at regular intervals of a desired angle with respect to an origin positioned at the common intersecti...
07/27/1976
3935643Methods of and means for measuring angles
Apparatus is provided for measuring both the angle between the vertical and a particular axis of a body and the azimuth angle of the displacement of such axis from the vertical. The body houses a trasnducer having a bar magnet mounted on the free end of a...
02/03/1976
 
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