Showing papers on "Solenoid published in 1982"

Method and apparatus employing received independent magnetic field components of a transmitted alternating magnetic field for determining location

Abstract: The location method uses relatively low frequency electromagnetic fields, e.g., 1-1000 Hz, for determining the relative position and/or orientation of a transmitting magnetic dipole antenna by using a vector field receiver. The transmitting antenna for subterranean location, is preferably a single axis, elongated solenoid with a ferromagnetic core. The receiving sensor may be a precise three-axis magnetic field detector of either a magnetometer or search coil type. Measurements are made for one or more positions of either the transmitter or receiver, or with one or more transmitters or receivers. The relative location of the transmitter and the receiver is calculated with respect to some known survey station by a method of successive approximations. The operating frequency is chosen to minimize field distortion from common steel structures, such as pipe, casing or railroad tracks, and to minimize field scattering such as from conducting inhomogeneities in the earth. Either the transmitter or receiver can be operated within metal structures such as casing. The method can be used for location of underground boreholes or pipelines; location of trapped miners; as a means of blind surveying such as in underground mines; or as a means of navigation such as in relatively shallow horizontal or vertical drilling and tunneling or in raise bore mining.

Precision medication dispensing system and method

Abstract: The implantable device includes a medication reservoir, a pulsatile pump and an absolute pressure transducer. The pumping pressure wave developed in the pumping chamber is measured by the absolute pressure transducer whose output is used to adjust the pulsing rate of the solenoid operated pump so that the programmed time averaged rate of infusion of medication into the body is precisely maintained throughout all operating temperature and pressure conditions.

D.C. Electromagnetic actuator

Abstract: An actuator driven by D.C. power suitable for use in actuating automobile door locking device. The actuator has a yoke apparatus defining a space, two annular solenoid coils supported and received by the yoke apparatus and adapted to be energized simultaneously such that poles of the same polarity appear at the adjacent ends of the coils, and moving means reciprocatably disposed in the space of the yoke apparatus. The moving means includes an axially magnetized permanent magnet carried by a shaft and a pair of magnetic members attached to both axial ends of the permanent magnet.

Control system for a power steering device

Abstract: A control system for a power steering device of a vehicle, wherein the rotational angular position of a steering wheel, the vehicle driving speed and the steering torque applied to the steering wheel are detected and processed by a digital computer. The computer selects one of plural control values stored in a memory device based upon the detected steering torque and the detected vehicle speed and outputs the selected one of the control values along with solenoid selection data which is determined based upon the detected rotary angular position data. An electric current having a value corresponding to the selected one of the control values is applied from a solenoid drive circuit to one of a pair of solenoids, so that a four-way open center type solenoid valve having the solenoids controls the supply and exhaust of pressurized fluid to and away from a power cylinder of the power steering device in accordance with the detected vehicle driving speed and the detected steering torque.

Hydraulic control system for electronic transmission control

Abstract: The hydraulic control circuit for an automatic transmission includes solenoid-operated clutch pressure valves which selectively connect line pressure to the selected clutch as the winding of the solenoids are energized and de-energized by an electronic control system. A solenoid feed valve and feedback valve operate to connect line pressure to the input port of the several clutch actuator valves, provided the clutch pressures are within certain limits. If these limits are exceeded, line pressure is disconnected from the actuator valves and is applied, instead, automatically and without respect to electronic control, to the clutches that produce a predetermined gear ratio. A coast control valve operates to regulate pressure to a servo that is pressurized at a lower level for low gear ratio operation and at a higher level for reverse drive operation. The coast control valve vents the servo if either of the clutches that produce the predetermined speed ratio are pressurized. A line pressure regulator and boost valve act in combination with an on-off valve whose state is determined by a solenoid. Minimum line pressure is established at a minimum value, determined by the pressure drops across two orifices whose sizes are predetermined, when the solenoid opens line pressure to a vent port. Maximum line pressure is determined by pressure forces developed on a boost valve when the line pressure regulator solenoid closes the boost line to the vent port.

A control circuit for a variable displacement air conditioning compressor

Abstract: A control circuit is disclosed for controlling the operation of a variable displacement device in an air conditioning compressor (10) in order to change the capacity of the compressor (10). The control circuit includes at least one solenoid (20) which controls the operation of one more valves in the variable displacement device. The solenoid (20) is connected to a voltage source (18) via a detecting device (21) which includes a pressure sensitive switch responsive to the pressure of the refrigerant in the air conditioning system at the inlet of the compressor (10). The detecting device (21) enables the solenoid (20) to decrease the capacity of the compressor (10) when the refrigerant pressure goes below a first predetermined pressure level and then disables the solenoid (20) when the refrigerant pressure exceeds a second predetermined level. The detecting device (21) also is responsive to the temperature of the refrigerant at the inlet of the compressor (10).

What do ``voltmeters'' measure?: Faraday's law in a multiply connected region

Abstract: A long solenoid carrying a varying current produces a time‐dependent magnetic field and induces electric fields, even in the region exterior to the solenoid where ∂B/∂t and therefore curl E vanish. By paying attention to (a) what it is that a ‘‘voltmeter’’ measures and (b) the simplest properties of line integrals (e.g., under what circumstances the line integral of E is path independent), it is easy to use Faraday’s law to predict the readings of voltmeters connected to various points in a circuit external to the solenoid. These predicted meter readings at first seem puzzling and paradoxical; in particular, two identical voltmeters, both connected to the same two points in the circuit, will not show identical readings. These theoretical predictions are confirmed by simple experiments.

Battery jump cable apparatus

Abstract: Apparatus for transferring power from the battery of a service vehicle to the battery of a second vehicle, wherein the final connection between the batteries is made from a remote location via a radio transmitter and a receiver which is mounted in the casing of the apparatus to actuate a solenoid in response to a signal from the transmitter. The circuit between the solenoid and the receiver includes a transistor to control current through the solenoid coil and the base of the transistor is connected to the battery of the second vehicle. Cables used to attach the apparatus to the second vehicle battery are wound on a spool having an interrupted ratchet on one end thereof, the ratchet engaging a ratchet lock that pivots in one direction to hold the reel when the reel is turned in one direction to pay out the battery cables and the ratchet lock pivoting in the other direction within a ratchet wheel interruption to permit free rotation of the reel in the opposite direction for retrieval of the cables on the reel.

Forward drive release system for automatic transmission

Abstract: A control system for reducing the torque applied to an automotive engine when the vehicle is idling and the transmission is set for operation in an acceptable drive range includes sensors to determine the manual gear selector position, output shaft speed, engine speed, turbine speed, and the throttle valve position. A solenoid operated valve opens and closes a source of high pressure fluid to a clutch whose engagement is required to transmit torque through the transmission from the engine to the drive wheels. An electronic computer is supplied with the digital equivalent of the shaft speeds, the position of the gear selector and of the throttle. An equation for determining the duty cycle of the solenoid valve coils is repetitively calculated through the use of a computer program algorithm. The equation corrects a previously calculated duty cycle with feedback error and terms that are proportional to the magnitude of the present error and the magnitude of the previous error.

Solenoid drive circuit

Abstract: A solenoid drive circuit for a matrix printer comprises a capacitor (C1) connected in parallel with the series arrangement of a first diode (D2), the solenoid coil (L1), and the collector-emitter path of a transistor (T1). A second diode (D3) is connected in parallel with the coil (L1) and transistor (T1). The capacitor is charged from a d.c. supply which includes a switching regulator (10, T10) via a diode (D1). When the transistor is switched ON by a print signal applied to a terminal (4) the capacitor is discharged resonantly into the coil. The first diode (D2) prevents current flow from the solenoid to the capacitor during the negative half cycle of the resonant frequency so that current in the coil circulates in the loop formed by the coil, the transistor and the second diode. When the transistor is switched OFF the current flowing in the coil is discharged via a further diode (D4) into the storage capacitor (C10) of the d.c. power supply to increase the efficiency of the drive circuit. The print signal is also fed to an inhibit input of the pulse width modulator (10) to switch OFF transistor (T10) during the print operation.

Solenoid valve for hot melt material

Abstract: A solenoid valve for controlling the flow of hot melt material such as hot melt adhesive. The valve includes an aluminum body in which is disposed a heater cartridge for supplying heat energy to the body. The body is bored to receive an insert constructed of brass of like material having good heat conductivity and the insert defines a cylindric passage. Extending through the cylindric passage is a valve stem that has an outer diameter less than the inner diameter of the cylindrical passage so that an annular flow path is formed. Hot melt material supplied to one end of the annular flow path flows to a valve seat at the other end of the flow path. The diameters of the cylindric passage and the valve stem are established so that the annular path has a sufficiently small radial dimension (e.g. 0.004 inch) that the hot melt material in the path is rapidly and efficiently heated so that when discharged through the valve seat it will be at a suitable operating temperature. A solenoid coil assembly is mounted exterior of the body by a threaded connection between the assembly and the body so that relative rotation therebetween changes the relative axial position of the solenoid assembly and the body. The valve stem is attached to a core within the solenoid assembly so that the stroke of the stem is adjusting the relative rotational position of the body and the solenoid assembly. Rigid with the body is a support housing formed of stainless steel or like low heat conductivity material. The solenoid assembly is attached to the housing so that flow of heat from the body to the solenoid is attenuated by the housing, and the solenoid thus operates at a relatively low temperature.

Control circuit for a solenoid-operated actuator

Abstract: A control circuit comprises a switching element connected in series with the coil of an actuator for generating a drive current when rendered conductive. A drive current sensing resistor is coupled in a circuit with the switching element and the coil to develop a first voltage in response to the switching element being rendered conductive. A surge current sensing resistor is coupled in a circuit with the coil through a unidirectionally conducting element to develop a second voltage in response to the switching element being rendered nonconductive. The first and second voltage are amplified and fed to a differential integrator to which an actuator control signal is also applied. The output of the differential integrator is compared with the instantaneous value of a ramp voltage to generate gating pulses applied to the switching element.

Small solenoid with a superconducting shield for nuclear‐magnetic‐resonance near 1 mK

Abstract: A small superconducting solenoid to provide the steady homogeneous field for NMR at ultralow temperatures is described. The solenoid is shielded by a superconducting tube and there is a simple method of computing the field distribution. Three different shield materials, Pb, Nb–Ti, and pure Nb, were investigated. The final version of the solenoid and shield gives a field of ∼0.5 T with a homogeneity of ∼5×10−4 over 1 cm with, heating of less than 0.1 μ W.

Solenoid current control

Abstract: The response time and power consumption of a solenoid-type actuator are minimized through exercising control over a transistor connected in series with the solenoid coil and a current source. Upon receipt of a command signal the series connected transistor is driven into saturation for a period of time commensurate with the current flow through the coil to rise to the level where a magnetic field of sufficient magnitude to pull in the solenoid plunger will be generated. The solenoid current is, once the solenoid armature moves, reduced to that level needed to maintain the field by controlling the transistor such that there is a constant voltage across the solenoid winding.

Fuel injection valve

Abstract: PURPOSE:To control open-close operation of a fuel injection valve at high speed CONSTITUTION:An iron core 1 and valve head 2 in a solenoid fuel injection valve are formed by a ferrite core Since the ferrite core can be used also in an extremely high frequency, an eddy current is hardly generated even for a very sharp rise-up of current in a solenoid core Accordingly, delay of the magnetic flux is not caused for change of a current, and the sharper the current is changed the sharper the magnetic force is caused, then the valve can be open- close controlled at high speed

Solenoid driving apparatus for actuating key of player piano

Abstract: A solenoid driving apparatus for actuating keys of a player piano is provided in which respective key striking strength data can be applied to respective solenoids of keys, so that musical tones can be reproduced correctly and in which the key striking strength data at the time of musical performance can be compensated for high fidelity reproduction. The solenoid driving apparatus includes a plurality of keys and solenoids provided on each key. When a key is depressed, a first key striking strength data corresponding to key striking strength and a data designating the depressed key are generated. The first key striking strength data is then converted into a second key striking strength data so as to make the latter data in linear proportion to an operating or response speed of the solenoid. In accordance with the second key striking strength data, a solenoid driving data is generated, and is applied to the solenoid corresponding to the key designated by the designating data. The solenoid driving data thus converted from the second key striking strength data causes musical tones to be reproduced as having correct timings and high fidelity.

Motor control for data disc rotating systems

Abstract: A system for rotating a data storage disc in a disc drive and for rapidly bringing the disc to a halt comprises a brushless motor fed with direct current in its windings by a motor drive circuit which current is also fed to a solenoid to hold a spring loaded solenoid arm from pressing a brake against a shaft to brake the disc, the motor control circuit using the current caused by back emf in the windings of the motor to provide motor braking while passing the current through the solenoid which applies the brake when the motor speed falls below a predetermined limit, the solenoid also being employed as a current smoothing choke

Active vibration isolator

Abstract: An active vibration isolator for removing vibration between a vibration source and a payload. The payload being various types of equipment such as measuring instruments, a camera, a vehicle seat, weaponry and other types of devices whose performance is sensitive to vibration. The isolator suspending the payload from a coil spring attached to the vibration source. A solenoid is mounted between the spring and the payload and an electrical control system is used to control the solenoid so the solenoid moves in an equal but opposite direction to the vibration on the spring thereby stablizing the payload.

Proportional solenoid valve

Abstract: A normally closed spool type solenoid-controlled valve which changes its opening in proportion to the amount of current supplied to the solenoid. The spool which blocks the valve opening in an overlapping relation is held in a closed position by a dual spring design having differing spring rates wherein the lighter spring holds the spool in an overlapping closed position.

System for controlling cooling water temperature for a water-cooled engine

Abstract: A system for controlling cooling water temperature for a water-cooled engine has a radiator, a cooling water passage communicating a water jacket in the engine with the radiator, and a thermostat provided in the cooling water passage. The system is provided with a bypass for bypassing the thermostat, a bypass valve provided in the bypass for closing the bypass, and a solenoid operated valve for actuating the bypass valve. Switch circuits are connected parallel to a solenoid of the solenoid operated valve means. The switch circuits comprise a thermo-switch responsive to low cooling water temperature to effect the operation of the solenoid operated valve for closing the bypass valve of the bypass, a vacuum switch responsive to a vacuum in the intake passage at heavy load operation of the engine to effect the operation of said solenoid operated valve for opening the bypass valve, whereby the cooling water temperature is controlled according to the engine operation.

Apparatus for stamping indicia on materials

Abstract: In a marking system for stamping materials such as aluminum strip, a pulse of determined energy is supplied to a solenoid, to impart a determined kinetic energy to a die. The die is guided to dissipate substantially all of this kinetic energy in the deformation of the material being stamped. The pulse of energy applied to the solenoid may be controlled by a programmable computer, programmed to control the duration of time that a current is applied to the solenoid. The computer may control a plurality of such solenoids, controlling the times and relative numbers of operation of each of the solenoids.

Auxiliary head lamp device for car equipped with cover

Abstract: The invention discloses an auxiliary head lamp device for a car equipped with a cover which is optionally fitted to a car and is lit during driving in fog or the like. The cover of this device can be opened when a solenoid of a cover driving mechanism is energized by operating a switch disposed inside the room of the car. The solenoid releases engagement of a stopper that restricts the cover urged in the opening direction. The switch may be used also as a switch for a light source bulb. After the solenoid is energized and the opening operation of the cover starts, a current to the solenoid is automatically cut off so that over-heat or burn-out of the solenoid that would occur if the current is continuously applied thereto can be prevented.

Multiple way pinch valve

Abstract: A miniature electromagnetic valve having a valve mechanism with three spaced parallel rods, a pair of generally semi-circular, resilient conductor tubes extending between the rods and a linear solenoid for selectively shifting the intermediate rod for selectively and individually pinching the tubes closed.

Pressure modulating valve assembly

Abstract: The pressure modulating valve assembly includes a solenoid coil, a yoke having curved support surfaces extending from one end of the coil to the other, and a resilient non-magnetic valve support having at least one valve secured thereto and a pair of attaching legs secured to the yoke in overlying relation relative to the curved support surfaces. An armature of magnetic material is secured to the valve support at a central portion thereof spaced from the point of attachment of the valve support to the yoke. A spring normally biases the armature in a direction away from the solenoid coil so that upon energization of the coil the solenoid support and the armature secured thereto are subjected to a rolling motion along the curved surfaces of the yoke to provide a friction free connection between the yoke and the combined armature and valve support.

Apparatus for generating uniform magnetic field

Abstract: PURPOSE:To compensate the magnetic field of an annular permanent magnet to form a uniform magnetic field, by a method wherein a pair of annular permanent magnets are provided so as to leave the interval therebetween toward the same direction and a circular magnetic field compensating member is provided to the space between said annular permanent magnets. CONSTITUTION:A magnetic field generating apparatus 15 is formed by providing a pair of annular permanent magnets 8, 9 so as to leave the space (a) therebetween in coaxial relation to each other while coaxially providing a cylindrical solenoid to the gap between the annular permanent magnets 8, 9. By this constitution, the formation of a uniform magnetic field is enabled by compensating the magnetic field of the annular permanent magnets and, because a power consumption amount can be remarkably reduced, running cost can be reduced, a cooling system become a small scale and apparatus cost is lowered.

Gas burner control system

Abstract: A burner system of the type in which a thermocouple or like EMF-generating sensor detects the presence of a pilot flame and controls a main fuel valve to hold the latter open as long as the pilot flame remains lit. According to the invention, the main valve is held open by a solenoid and a resistance is provided in circuit between the sensor and the solenoid to reduce the response time of the latter which results from the inductance contributed by the magnetic coil forming the solenoid.

Control circuit arrangement for an electromagnetically operated power tool

Abstract: A control circuit arrangement for an electromagnetically operated power tool has a primary circuit including a solenoid and a semi-conductor switch, in series, the semi-conductor switch being capable of being triggered into a conducting state upon application of a trigger signal from a trigger control circuit. The trigger control circuit is actuated upon closure of a main trigger switch which is connected in series with the solenoid and the semi-conductor switch in the primary circuit for supplying current to the solenoid. Thus, should the semi-conductor switch fail due to a short-circuit, the power supply is disconnected from the solenoid the moment the operator releases the main trigger switch so protecting the solenoid. The semi-conductor switch is preferably a thyristor. An additional circuit is preferably provided for preventing the thyristor from firing a second time if the main switch remains closed. A delay circuit is also preferably provided for delaying firing of the thyristor until some time after the main switch has been closed to prevent arcing and damage to the main switch contacts.

One shot firing circuit for power tools

Abstract: A one shot firing circuit for electrically powered tools is described which includes a manually operable normally open trigger switch connected electrically in series with a solenoid coil and an AC power source for controlling the supply of electrical power to both the firing circuit and the solenoid, such that when the trigger switch is open, the path of current flow to the solenoid coil is physically interrupted. The firing circuit also includes an SCR connected electrically in series with the trigger switch, the solenoid coil and the AC power source, for controlling the flow of current through the solenoid coil after the trigger switch has been closed. The firing circuit further includes a timing circuit connected to the gate of the SCR which is operable in response to the closing of the trigger switch to provide a predeterminable delay after the trigger switch is closed before enabling the SCR to conduct and permit a unidirectional current impulse to flow through the solenoid coil of sufficient magnitude to energize the solenoid. The timing circuit also operates to disable further unidirectional current impulses through the solenoid coil once the solenoid has been energized until a predeterminable delay after the trigger switch has opened.

Magnetic disk storage device

Abstract: PURPOSE:To prevent a magnetic disk and a magnetic head from being damaged by an external force such as the external vibration, etc. when the disk is stopped, by providing a mechanism for separating the magnetic head from the magnetic disk face when the disk is stopped. CONSTITUTION:An arm 5 of a protecting mechanism is fitted to a shaft 3 connected to a solenoid 15 with a screw 17, and in order that it is rotated in the direction as indicated with an arrow 4 when the solenoid 15 is de-energized, a spring 18 is incorporated. When a magnetic disk 1 is rotated, the arm 5 is in a shunted position of 5' by energizing of the solenoid 15, but when the disk 1 is stopped, a carriage 8 moves to a position of a stopper 14, a magnetic head 2 is fixed, also the arm 5 is rotated in the direction as indicated with an arrow 4, its tip press-pushes a plate spring 7, and the head 2 is pressed in the direction for separating it from the disk 1. Therefore, it is possible to prevent the disk and the head from being damaged by external force such as external vibration, etc.

Window security system

Abstract: The following disclosure shows a window security system. The window security system comprises a grate or security bar assembly that is hinged to the outside of a window and includes louvres attached to the grate for protecting against the elements and in particular, sunlight. The grate is hinged to the window at one side, while on the other side, it is secured by means of a latch comprising a pointed latch pin which is engaged by a pair of jaws that are pivotally actuated by a toggle member. The toggle member can be actuated by a solenoid or by a hand operated cable or other assembly attached thereto. The solenoid can be either pushbutton operated or operated by means of a smoke detector. The entire assembly, including the grate and the louvres are opened at the time of the smoke detector detecting combustion to protect against entrapping occupants in the building.