Abstract: An instrument has a crossed-coil-type movable magnet in which a movable magnet rotatable about the shaft of a pointer needle is installed in a crossed coil unit and a measured quantity or the like is operated by supplying electric power to the crossed coil unit. The instrument includes an input unit to receive an input from a measurement object to be measured, an arithmetic section or ROM to set directions and time values for supplying electric current to the coils of the crossed coil unit, and a circuit section to deliver pulse signals with predetermined potential values to the crossed coils under conditions associated with the directions and time values, to provide a very broad angular range of the pointer needle.

Abstract: A tachometric device is provided with a D.C. electric motor a shaft of which drives a pair of permanent magnets to rotate. A first permanent magnet controls a speed indicator unit; a second permanent magnet is rotatably mounted within a winding the terminals of which are connected to a negative feed back circuit for controlling the speed of the motor.

Abstract: An electromagnetic power generating type rotation sensor has a magnetic pole which is divided into an inner magnetic pole piece and an outer magnetic pole piece (3a, 13a) located in a position close to an outer peripheral part or a side part of a magnetic rotator. The inner magnetic pole piece (3b, 13b) is located adjacent to the outer magnetic pole piece but inside the sensor so as not to be exposed to the external environment.

Abstract: A vehicle tachometer kit including a pick up coil that is adapted to be mounted on the outside of the vehicle's alternator to sense its rotating field without any disassembly. An induced signal in the coil from alternator field leakage provides the normal input to a user calibrated r.p.m. display driving circuit in the tachometer that can be calibrated for different alternators and drive pulley ratios without another tachometer by selectively applying a simulated input reference signal to the display driving circuit and adjusting the r.p.m. display until a scheduled ratio is achieved between the displayed r.p.m. and the reference signal.

Abstract: Rotary type knotmeters designed to detect relative motion between an underwater vehicle and the water in which it is submersed at relatively great depths comprise a vaned rotor external unit, an electronic counter/display internal unit, a multiplexing transmission line connecting the external unit to the internal unit and, preferably, a brake unit to stop rotation of the rotor unit when the knotmeter is not immersed in water. The external unit comprises a plurality of spaced Hall-effect magnetic sensors that function with bi-phase electronic detectors to modulate current flowing in the transmission line to power the external unit. Such detectors count the number of rotations per unit time of the vaned rotor which is proportional to the relative motion between vehicle and water. The current is demodulated in the internal unit to produce a velocity value which is then displayed as a digital speed reading.

Abstract: In an MWD measurement system, the speed of rotation of a downhole turbine is measured by the interaction of a triaxial magnetometer in a sensor package and a permanent magnet attached to the turbine shaft. The triaxial magnetometer may be part of an existing MWD system for measuring borehole directional parameters. The magnet is a strong magnet mounted on the turbine shaft perpendicular to the axis of the turbine and the axis of the drill string.

Abstract: A modularized marine instrument sensing device is described wherein a paddlewheel assembly for providing an electromagnetic signal proportional to marine vessel speed is separably mountable on retaining members provided in a sensor housing. The sensor housing may house a Hall-effect device which converts the varying magnetic field from the paddlewheels to an electrical signal proportional to vessel speed. The sensor housing may also incorporate a piezoelectric transducer for providing a depth sounding and fish finding function. Optionally, the paddlewheel assembly may include a temperature sensing device, such as a thermistor, within a frame assembly which incorporates locking tabs and engagement pins which cooperate with the retaining members on the sensor housing.

Abstract: A marine speed sensor mounted in a housing which may also include a temperature sensor and a sonic transducer. The speed sensor includes a paddlewheel for producing an electromagnetic field. The paddlewheel is rotatably mounted adjacent the housing and exposed at top and bottom and mounted between support members extending from the housing.

Abstract: A system for detecting mechanical movement of a body under detection formed of: a synchro generator having a primary and a secondary windings, one of which is capable of being coupled to the body; an exciting circuit for providing exciting current to the primary winding; a reference signal generator for providing a reference signal of a predetermined frequency; a first circuit producing pulses at a frequency which changes depending on the phase difference between the reference signal and the signal induced in the secondary winding; and a frequency-divider counting the pulses and producing a first digital signal indicative of the count value at each moment. The first digital signal is supplied to the exciting circuit which determines the instantaneous value of the exciting current at each moment.

Abstract: A marine speed sensor mounted in a housing which may also include a temperature sensor and a sonic transducer. The speed sensor includes a paddlewheel for producing an electromagnetic field. The paddlewheel is rotatably mounted adjacent the housing and exposed at top and bottom and mounted between support members extending from the housing.

Abstract: In a vane compressor, a rotational speed sensor for sensing the rotational speed of the rotor comprises a permanent magnet embedded in an end face of the rotor, a pin formed of a ferromagnetic material, rigidly fitted in a pump housing accommodating the rotor, with its one end disposed to encounter the permanent magnet, and a magnetically sensing element disposed opposite the other end face of the pin.

Abstract: In a highly compact odometer an electric motor which drives a mechanical display thereof, is disposed within the set of annular figure wheels used in the display and drivingly connected to said wheels through a worm and worm wheel drive train. In the case of integrated "total" and "trip" odometers a multipole rotor having a torque capacity adequate for driving both odometers is disposed within the set of figure wheels used for the "total" odometer display while the coil is disposed within the "trip" odometer set. Yokes extend between the sets of wheels to provide a magnetic connection between the coil and rotor. To prevent reversing of the odometer and gear chatter in the drive train a one-way clutch type bearing is used to support the output shaft of the electric motor.

Abstract: A system for detecting mechanical movement of a body under detection comprises: a synchro generator having multiple-phase primary windings and a secondary winding, either of the primary windings or the secondary winding capable of being coupled to the body, and a phase-shifting circuit phase-shifting the secondary induced signal by 90.degree.. A phase comparator determines the phase difference between a set of two-phase reference sinusoidal signals and a second set of two-phase signals consisting of the induced signal and the phase-shifted signal. A frequency-divider counts pulses of a frequency proportional to the phase difference and produces a digital signal indicative of the count value at each moment. An exciting circuit for exciting the synchro generator determines the instantaneous values of the exciting voltage in accordance with the count value of the frequency divider.

Abstract: A frequency detector comprising first, second and third conductive patterns. The first conductive pattern includes an even number of first straight conductive pieces which are disposed radially at regular intervals and sequentially connected in series alternately through first inner periphery conductive pieces and first outer periphery conductive pieces. The second conductive pattern includes an even number of second straight conductive pieces disposed radially at predetermined intervals between the adjacent two first straight conductive pieces at the outer periphery sides of the respective first inner periphery conductive pieces and connected in series. The third conductive pattern includes an even number of third straight conductive pieces disposed radially at predetermined intervals between the adjacent two first straight conductive pattern at the inner periphery sides of the respective first outer periphery conductive piece and connected in series.

Abstract: A device to make a measurement of a variable quantity such as the speed of rotation of a first shaft or the speed of operation of an ignition system of an engine, wherein electrical pulses are produced at a frequency which is a function of the speed. The device comprises fixed first and second coils having axes in a common plane, and the planes of the coils are disposed at right-angles. Square waves corresponding to the pulses energize the first and second coils alternately, and each successive energizing of each coil is in an alternate direction, thus the magnetic field produced by the coils rotates continuously and rotates a disc magnet within the coils about an axis in the planes of the coils at an angular velocity which is a function of the speed. A rotor of conducting material in the form of a cylindrical cap over and about the magnet is integral with a second shaft coaxial with the magnet.

Abstract: A voltage generator which provides the biasing voltage to a telemetry transmitter positioned inside the tire of a moving vehicle is disclosed. The entire transmitting system, including the antenna, is self-contained within the pneumatic tire; and, accordingly, there is no need for connecting wires of any nature to be extended outside the tire containing the invention. The invention utilizes one of several available types of voltage generators to generate a voltage in response to the rotation of the tire as the vehicle moves within a coil. As is known, as a tire rotates along a road, the tire deflects and flattens along the area which contacts the road. The transducer used in the invention generates a voltage in response to this tire deflection. The voltage thus generated are processed and utilized to provide the biasing voltage for a transmitter.

Abstract: A speed measuring sensing device for producing a signal corresponding to the relative angular rotation between two structural members including a rotor arranged on the rotating member and a stator mounted on the stationary member. The stator is separated from the rotor by an air gap. The rotor includes a plurality of magnetizable sectors which vary the magnetic field while passing a pole shoe of the stator. The surface area of each of the magnetizable sectors of the rotor and the surface area of the pole shoe of the stator exhibit a maximum ratio of 1 to 1.

Abstract: A rotatable disk having a plurality of calibration segments and at least one marker along the peripheral portion thereof is provided while a stationary pick-up provided adjacent the disk for generating a first signal indicative of calibration segments and a second signal indicative of a reference position of the rotation of the disk. The frequency of the first signal is increased in order to accurately measure the rotational angle from the reference position.

Abstract: A device (1) for transmitting rotary motion from a first to a second shaft and for measuring the angular speed of said rotary motion, comprising a first and second pulse generator associated respectively with said first and second shaft, and governing, by means of a processing circuit, the operation of an electric motor (2) of direct current type one shaft (7) of which is torsionally coupled to said second shaft; and a speed indicator comprising means (25) sensitive to magnetic field variations is described. The main feature of this device (1) is that said second pulse generator comprises a magneto-electrical transducer (32), and a permanent magnet (9) is torsionally coupled to said second shaft; said magnet (9) determining the activation either of said magneto-electrical transducer (32), or of those means (25) of said speed indicator which are sensitive to magnetic field variations.

Abstract: An air core gage having a pair of coils in quadrature to drive a pointer has the first coil energized by a relatively constant reference current while the second coil is energized by a current which varies as a tangent function of the input quantity in order to drive the pointer through an octant of the gage. The current polarity to the second coil is reversed and the current is again varied in the same manner to vary the pointer through a second octant. Then, the reference current is applied to the second coil and the current is varied in the first coil according to the tangent function to drive the pointer through a third octant, and so on for a wide angle pointer drive. When the input quantity is a frequency, the driving circuit is conveniently a digital circuit including a ROM which stores the tangent function of the input quantity and a steering logic circuit which selectively applies the steady state and the variable signals to the gage coils to effect the appropriate pointer movement.

Abstract: Improvements are provided for a vehicle locator system of the type in which vehicle-borne emitters radiate coded tone combinations for reception by spaced sensors which are linked to a central decoding office. In one improvement the vehicle capacity of the system is increased without increasing the number of tone oscillators by using a sequential tone coding arrangement wherein each oscillator is switchable to provide a different tone during different intervals in the coding sequence. In addition, the pulsing rate of the emitted tone is synchronized to the vehicle odometer to assure that a code sequence is transmitted while the vehicle is in the proximity of each sensor station.

Abstract: A detector for a movalbe member such as a rotatable shaft includes a sensor and an alarm having a normal and a signaling condition. The sensor includes one or more magnetic pole pieces attached to the shaft whose rotational speed is to be detected, to rotate in unison therewith, and a pick-up including a coil mounted adjacent the shaft for producing an electrical signal in response to the rotating magnetic pole pieces. An electrical circuit is provided, connected between the coil and the alarm for switching the alarm between its normal and signaling conditions in response to a predetermined value of the electrical signal. The position of the coil with respect to the shaft and magnetic pieces is adjustable for selectively producing the predetermined switching value of the electrical signal in response to different rotational speeds of the shaft.

Abstract: My invention relates to ship'logs and speedometers, comprising magnetometers and associated circuitry located inside the hull of the vessel, for accurately sensing, indicating, and recording the revolutions of an external rotator equipped with a small permanent magnet assembly. The rotator with a low-friction bearing arrangement is suitably located outside and below the hull of the vessel so that its rotation accurately registers the movement of the vessel through the water. The elimination of any mechanical or electrical connection between the rotator and the inside sensing components of the magnetometer assembly facilitates removal of the rotator for maintenance and substantially reduces the risk of leaks through the hull of the vessel.

Abstract: Low pressure in a vehicle tire is detected by an electronic system which compares the difference in phase between two cyclic signals and produces an output signal having a negative going pulse and a positive going pulse for each revolution of the tire. Each negative going pulse represents a decrease in phase between the two signals and is generated in response to a shorted coil passing through an electromagnetic field produced by an induction coil in a parallel resonant circuit which produces the second of the two signals. The first signal is produced by an oscillator and is used to excite the resonant circuit and as a reference signal. The coil is shorted by a closed switch in the tire when the pressure is normal. Abnormal tire pressure opens the switch and renders the coil ineffective. Each positive going pulse represents an increase in phase between the two signals and is generated in response to a ferrous metal plate passing through the field.

Abstract: The invention relates to a device for checking the angular position and the starting position of a roller supporting a plurality of indicating pallets, which roller is driven in stepwise rotation. The device comprises magnetic members adapted to sense the position of magnetic poles provided on the roller or on a member mechanically linked to the roller, whereby the number of steps taken by the roller, starting from a predetermined position, can be counted taking advantage of a circumferentially arranged Hall effect and without contact between the sensing members and the roller or the member mechanically linked thereto.

Abstract: A system for monitoring the operation of a plurality of rotating-shaft machines, including a switchable meter to indicate the shaft speed of any one of these machines. Each machine has a monitoring circuit including respective visual warning branch circuits to indicate if the machine shaft falls below a first preset speed and then to indicate if the machine shaft falls below a second preset speed, with provision for sounding an audible alarm. The system has a single power supply, switchable meter, audible alarm control circuit and warning reset circuit, and identical monitor modules for the respective machines to be monitored. Each module has an external sensor, consisting of a pickup coil and a magnet assembly attached to the rotating shaft of the monitored machine; a high-gain integrated circuit amplifier to amplify the pulses from the sensor; circuitry to convert the pulses to a D.C.

Abstract: An air core gauge is provided with a plurality of angularly oriented coils. Switching means are connected to the coils in order to control the flow of current therethrough. Pulse generators responsive to variations in frequency of electrical signals representative of a condition, such as vehicle speed or engine RPM, control the switching means so as to cause excitation of the coils to produce a resultant mmf vector, the angular position of which is related to the frequency of the signals. The resultant mmf vector causes a magnet and associated pointer to rotate to thereby provide an indication of the value of the condition.