Showing papers on "Solenoid published in 1984"

Calibration of ac susceptometer for cylindrical specimens

Abstract: The absolute magnetic susceptibility of cylindrical specimens is obtained with an ac susceptometer whose calibration is based on a calculation of mutual inductance. An axially magnetized cylinder is modeled as a solenoid of the same size. The mutual inductance between such a solenoid and a pickup coil of arbitrary dimensions is computed. The susceptibility is then a function of the mutual inductance, the cylinder length, the magnitude and frequency of the ac magnetizing field, and the voltage induced on the pickup coil. Demagnetization factor and eddy‐current effects are considered, an example is given, and pickup coil compensation is discussed. Other calibration methods are also presented.

Power steering device

Abstract: PURPOSE:To improve the sense of steering during high speed running by generating auxiliary steering power when the steering power exceeds the first set point and car speed is below a specified one and generating the auxiliary steering power independently of the car speed when the steering power exceeds the second higher set point CONSTITUTION:When steering power exceeds the first set point and is below the second set point during steering, a steering power sensor 22 issues an output signal to the contact 21 of a relay 19 At this time, if the car speed is below a specified value, a car speed sensor 18 issues a low speed signal Thus, a solenoid 20 is excited and the contact 21 is closed As a result, since the solenoid 24 of a relay 23 is excited and a contact 26 is closed, a motor 10 is started If the car speed exceeds the specified value, since the sensor 18 will not issue the signal, the contact 21 is opened and the motor will not be started If the steering power exceeds the second set point, the sensor 22 directly issues the output signal to the solenoid 24 without interposing the contact 21 and the contact 26 is closed Consequently, the motor 10 is started in this case independently of the car speed

Pulse controlled solenoid valve

Abstract: A pulsed controlled solenoid flow control valve suitable for use in a closed vapor cycle air conditioning system is disclosed. A pulsewidth modulated control signal is generated for cyclically opening and closing the flow through the expansion valve. The duty cycle of the pulsed control signal determines the average flow rate through the valve. An exponential response control curve is used in conjunction with an integrator offset to obtain a single set point control operating point for all flow rates through the valve, where a given change in the second superheat of the evaporator produces the same percentage change in flow rate regardless of the flow rate.

Door latch mechanism

Abstract: A door latch mechanism has a pivoted latch disposed be­ tween a retaining solenoid and a four-bar toggle linkage. The toggle linkage connects the operating stem of the solenoid to the latch, has an under-the-center arrangement in a direction away from the solenoid in the latched position of the mecha­ nism, and provides a substantial mechanical advantage to am­ plify the holding force of the solenoid. When the solenoid is de-­ energized and pressure is applied to open the door, the latch pivots and the toggle linkage collapses to release the keeper bar. The keeper bar is trapped but has a limited movement in both horizontal and vertical directions in a plane substantially parallel to the pivot axis of the latch. the overall arrangement is relatively simple, compact, inexpensive, easy to install, and re­ liable in its operation.

Variable reluctance actuator having position sensing and control

Abstract: A controlled force variable reluctance actuator. A variable reluctance actuator having a moving element operated by a solenoid is provided in which the current in the solenoid is controlled by a signal representative of the flux density in the magnetic circuit of the actuator. The signal is produced by a Hall effect device placed in the magnetic circuit. Preferably, the Hall effect device controls the current in the solenoid by controlling its duty cycle; however, continuous control of the current may also be employed. Alternative embodiments are provided for a constant force actuator, an actuator whose force-displacement characteristic is altered, and an actuator in which the force may be selectively controlled. An embodiment is also provided for selectively controlling the position of the moving element based upon measured electric and magnetic parameters of the actuator.

Water saving system

Abstract: A water saving system for preventing the waste of water which falls below a predetermined temperature, which system includes a recirculating pipe line extending from an outlet faucet back to a heating device and which system is appropriately controlled thermostatically by a series of temperature sensing devices. The system includes a solenoid control valve which prohibits the delivery of water, which is below a predetermined temperature but which is appropriately controlled to be opened when the water in the delivery line is sufficiently heated. The system further includes a pump, which is energized to recirculate cooled water back to a heating source and which pump is de-energized when the water in the delivery line is at the desired predetermined delivery temperature.

Modulator for hydraulic brakes

Abstract: This invention is a braking force modulator for hydraulic vehicle brakes which is intended to be inserted into the braking fluid conduit between the main cylinder or the like and one or more of the wheel braking cylinders and controlled by a sensor system for performing braking force modulation. The braking force modulator comprises a piston pump unit (12) with normally open inlet and outlet valves (37, 38) adapted to be closed under the action of a solenoid device (47, 48, 49, 52) whereby the unit is conditioned to act as a piston pump. The inlet and outlet valves (37, 38) are two mutually independent units adapted to be operated individually by one solenoid device each.

Aharonov-Bohm effect as a scattering event

Abstract: The Aharonov-Bohm effect is reconsidered as a scattering event of an electron by a magnetic field confined in an infinite solenoid of finite radius both in the situation where the solenoid is penetrable as well as impenetrable. We next discuss the validity of the Born approximation for the partial-wave scattering amplitudes and explain why for the cylindrically symmetric $(m=0)$ partial wave the first Born approximation fails in the long-wavelength limit or as the radius of the solenoid shrinks to zero.

Method for sensing and controlling the position of a variable reluctance actuator

Abstract: A controlled force variable reluctance actuator. A variable reluctance actuator having a moving element operated by a solenoid is provided in which the current in the solenoid is controlled by a signal representative of the flux density in the magnetic circuit of the actuator. The signal is produced by a Hall effect device placed in the magnetic circuit. Preferably, the Hall effect device controls the current in the solenoid by controlling its duty cycle; however, continuous control of the current may also be employed. Alternative embodiments are provided for a constant force actuator, an actuator whose force-displacement characteristic is altered, and an actuator in which the force may be selectively controlled. An embodiment is also provided for selectively controlling the position of the moving element based upon measured electric and magnetic parameters of the actuator.

Time delay undervoltage release

Abstract: A time delay undervoltage release for an electric circuit breaker causes the circuit breaker to trip when the control voltage drops below an acceptable level and prevents the breaker from being closed until the control voltage rises to a predetermined level. When the control voltage drops below an acceptable level, the undervoltage release energizes a trip solenoid to trip the breaker. A variable delay is interposed between the control voltage dropping below the acceptable level and the trip solenoid being energized. At the same time the trip solenoid is energized, an inhibit solenoid is deenergized to block the operation of the push-to-close button. When the control voltage increases to a predetermined level, the inhibit solenoid is energized, allowing the push-to-close button to be manually operated and the breaker returned to service.

Solenoid-controlled valve

Abstract: A solenoid-controlled valve of the present invention is provided with a valve housing having first, second and third ports, first and second movable members housed in the valve housing to freely move along its longitudinal axis and is made of magnetic material, and a magnetic circuit for magnetically attracting the first and second movable members independently in order to move them in the direction of the axis. The magnetic circuit includes a solenoid, a magnetic flux by-pass for by passing the second movable member, and a magnetic resistance attached to that portion of the magnetic circuit which is by-passed by the magnetic flux by-pass. The solenoid-controlled valve further has first and second valve members, which are actuated by the movement of the first and second movable members in the direction of the axis to independently open and close the first and second ports.

Electromagnetic fuel injector with tapered armature/valve

Abstract: An electromagnetic fuel injector is provided with a tapered armature valve plate operatively positioned by means of a locator so that it is arranged so as to, in effect, pivot from a spring biased position at which it seats against a valve seat associated with a plurality of orifice discharge passages located concentrically about the axis of the injector to a second position adjacent to the working surface of the pole piece means of the associate solenoid. Preferably, the electromagnetic fuel injector is of the bottom feed type whereby it can be supplied with fuel in excess of the amount to be injected, with the flow path of fuel being arranged so that the excess fuel will purge vapors from the injector and cool the solenoid coil therein.

Electromagnetic unit fuel injector with piston assist solenoid actuated control valve

Abstract: An electromagnetic unit fuel injector includes a pump assembly having an external actuated plunger reciprocable in a bushing with flow therefrom during a pump stroke being directed to a fuel injection nozzle of the assembly. Fuel flow from the pump can also flow through a passage means, containing a normally open, substantially pressure-balanced control valve actuated by a solenoid assembly in the valve closing direction to block drain flow during a pump stroke, as desired. A piston, actuated by discharge fuel pressure is operatively connected to the control valve to assist the solenoid in holding the control valve in a closed position.

Power steering control apparatus

Abstract: A power steering control apparatus for a car in which, under normal conditions, the steering becomes heavy as the speed of the car increases for the purpose of safety. This is realized by means of a hydraulic valve controlled by the reaction oil pressure of a proportional solenoid in the steering mechanism. In an abnormal condition such as the shortcircuit between solenoid coils or the failure of an electric control circuit, the proportional solenoid is deenergized through a failsafe circuit due to the fact that a feedback signal from the solenoid has become zero and the error with a high amplification gain between the car speed inverse proportional signal and the feedback signal has exceeded a first predetermined value. On the occasion of the voltage reduction of the power source for the electric control circuit and/or the increased temperature of the proportional solenoid, the failsafe circuit is disabled by an error protection circuit only when the difference between the car speed inverse proportional signal and the reduced feedback signal exceeds a second predetermined value.

Electric starting system

Abstract: An electric starting system for cranking an internal combustion engine that utilizes a starter having a solenoid that is provided with pull-in and hold-in coils. The solenoid includes a plunger which when shifted operates solenoid switch contacts and shifts a pinion into mesh with the ring gear of the engine to be cranked. The electric starting motor has series and shunt field coils and during cranking operation the shunt field is energized through the hold-in coil of the solenoid and the series field is energized through the pull-in coil of the solenoid. This mode of energization produces a small indexing torque that slowly rotates the pinion when end tooth abutment occurs between the pinion and the ring gear.

Exhaust gas purifier for internal combustion engine

Abstract: PURPOSE:To attain a high purification efficiency through the utilization of the oxygen retaining function of a ternary catalyst, by connecting the negative pressure of a variable-Venturi-part carburetor through a solenoid valve which is opened and closed at a constant frequency of about 1Hz to 2Hz and by determining the cross-sectional area of the valve so that the average of the air-fuel ratio of a mixture is nearly equal to a theoretical air-fuel ratio and the fluctuation width of the actual air-fuel ratio is about + or -0.2 to + or -1.0 as to the average. CONSTITUTION:A solenoid drive circuit 60, which generates rectangular pulses of 1Hz to 2Hz in frequency, energizes a solenoid 56 to open a valve port 53 to introduce air into a negative pressure chamber 20 from an air filter 51. Consequently, a suction piston 8 is moved toward a Venturi part 13 to intensify the negative pressure in it to cause a sucking action for fed fuel. For that reason, a mixture is thickened. A thick mixture and a thin mixture are thus alternately introduced into an engine cylinder. The dimensions of the valve port 53 are determined so that the average of the air-fuel ratio of the mixture is nearly equal to a theoretical air-fuel ratio and the fluctuation width of the actual air-fuel ratio is about + or -0.2 to + or -1.0 as to the theoretical ratio. This results in providing a high purification efficiency through the oxygen retaining function of a ternary monolithic catalyst 5.

Apparatus for controlling the rolling of an engine

Abstract: When detecting means detects that changes have been achieved by an automatic transmission in lever position and/or gear position, a solenoid drive circuit is actuated for a predetermined period of time to drive shock absorbers which control the rolling of the engine of an automobile. More specifically, when it is actuated, the solenoid drive circuit energizes solenoids, whereby the rotary valves of the shock absorbers are rotated for said period. As a result, one of the two orifices of either shock absorber is closed, thus increasing the force damping the vibrations of the engine. Hence, the vibrations caused by a large torque of the engine are not transmitted to the chassis of the automobile.

Magnet system and method of its manufacture

Abstract: A magnet system for providing a localized, substantially homogeneous magnetic field for use in nuclear magnetic resonance imaging. The magnet system includes a vacuum vessel defining a bore for receiving the subject of the imaging. It further includes a cryogenic containment vessel supported within the vacuum vessel. A single coil or "simple" solenoid is positioned within the containment vessel for providing the magnetic field. This coil includes a winding made up of thousands of turns of small superconductive wire, with the winding having a modular geometry including a plurality of axially spaced wire modules. The coil further includes an insulative substance, having a greater coefficient of thermal contraction than that of the wire, distributed in the winding. As the temperature of the coil is reduced from room temperature to its cryogenic operating temperature, the development of localized stress concentrations of sufficient magnitude to rupture the wire, are avoided. A method of winding the coil is also disclosed.

Torque fluctuation control device of engine

Abstract: PURPOSE:To improve the deceleration performance during running by providing an electric driving device and a power generating device applying positive and reverse torque to a crank shaft and performing the torque control in the direction to increase the braking action during the partial-cylinder operation and deceleration, in particular. CONSTITUTION:Two types of rotary solenoid coils 8, 9 and a magnetic body 10 are provided on the outer periphery of a flywheel 2 fitted to the end of a crank shaft 1. A stationary solenoid coil 7 is provided on the inner periphery of a fitting member 6 fixed to a cylinder block 3 around the flywheel 2. An electric driving device applying positive torque to the crank shaft 1 is constituted by exciting the stationary coil 7 and the rotary coil 8, and a power generating device applying reverse torque to the crank shaft 1 is constituted by exciting the rotary coil 9 with the stationary coil 7 connected to a rectifying circuit. The torque control is performed so that the reverse torque applied by the power generating device is corrected during the partial-cylinder operation and deceleration more than during the normal operation.

Hydraulic controller of automatic stepless speed changer for vehicle

Abstract: PURPOSE:To increase durability of solenoid valves, by directly supplying the oil pressure from a hydraulic pressure source to the hydraulic servo of an input pulley via a shift sequence mechanism and an input pulley modulator valve mechanism not through a speed reduction ratio control valve at steady running operation of a speed changer. CONSTITUTION:The oil pressure from a hydraulic pressure source 20 is directly supplied to the hydraulic servo of an input pulley 150 in a V-belt type stepless speed changer 140 at its steady running operation via a shift sequence mechanism 60 and an input pulley modulator valve mechanism 66 not through a speed reduction ratio control valve 51 operated by upshift and downshift solenoid valves 55, 56. Accordingly, a speed, at which driving power of an engine in each throttle opening is balanced with running resistance on the fixed land, is obtained, and its necessary hydraulic servo pressure of the input pulley is supplied from tne input pulley modulator valve mechanism, causing a number of on-off operating times of the solenoid valves 55, 56 to decrease at steady running and downshift maintaining time of a speed reduction ratio control mechanism, thus durability and reliability of the valve can be improved.

Electromagnetic unit fuel injector with cartridge type solenoid-actuated valve

Abstract: An electromagnetic unit fuel injector for use in a diesel engine includes a housing with a pump therein defined by an externally actuated plunger reciprocable in a bushing and defining therewith a pump chamber open at one end for the discharge of fuel to a spring biased, pressure actuated fuel injection nozzle. The pump chamber is also connected to a first chamber via a solenoid actuated, normally open, hollow pressure balanced poppet valve controlled passage to permit the ingress and egress of fuel. The first chamber adjacent to one end of the valve is in flow communication with a second chamber at the opposite end of the valve and these chambers are connected to a drain passage and supply passage, respectively. During a pump stroke, the solenoid can be energized to move the valve in position to block flow from the pump chamber to the first chamber so as to allow the pressurization of fuel by the pump to effect discharge of fuel from the injection nozzle. In a preferred embodiment the solenoid actuated poppet valve is a cartridge type assembly which is adapted to be received in a suitable socket provided for it in the housing and to be secured therein in hydraulic sealed relationship.

Ball-type vacuum valve for leak detection apparatus

Abstract: In a system for leak detection having many valves, it is desirable to have high vacuum valves operated by solenoids at opposite ends of a diffusion pump in order to isolate the diffusion pump during powr failure or during an intentional shutdown. A valve having a hard spherical ball fitting a vacuum seal and having a spring means to bias the ball in a closed position will close during a power failure. A bell-shaped actuator connected to a solenoid can be used to open the valve with built-in mechanical advantage. A circuit means can be used to supply high starting voltage to the solenoid and then lower voltage to hold the valve open.

Control means for precision control of valves

Abstract: Control means for precision control of valves having a through opening (7) which is steeplessly adjustable by means of a valve member (10) which is movable within the valve. According to the invention one end of the valve number (10) is rigidly connected to one end of a rod-like control element (16) of giant magnetostrictive material consisting of an alloy between rare earth metals and iron, cobalt or nickel, particularly an alloy between one or several of terbium, dysprosium, samarium and iron. The opposite end of the control element (16) is attached to a rigid supporting structure and is preferably prestressed in the intended direction of movement, e.g. by means of a spring (19). The control element (16) is surrounded by a solenoid (21) for generating a magnetic field acting upon the control element, said magnetic field being proportional to the supply of current to the coil. The control means further include a control device (37) for control of the supply of current to the solenoid in dependence of selected parameters and in accordance with a predetermined program.

Solenoid driver with switching during current decay from initial peak current

Abstract: A solenoid driver circuit has reduced power consumption by switching the solenoid coil current during a decay period from an initial peak current to a lower magnitude sustaining peak current. Current decays from the sustaining peak current magnitude for a predetermined length of time to a lower current level. Two transistors and a Zener diode are operatively connected to the solenoid and controlled by a logic circuit to apply the desired current to the solenoid. A sense resistor is coupled in series with the solenoid to sense current in the solenoid. The Zener diode is coupled in parallel with the sense resistor to provide a current decay path from the solenoid parallel to the sense resistor. The two transistors are turned on and off using logic flip-flops to sense voltage comparisons with the initial peak current voltage, the sustaining peak current, and the sustaining low current. A logic signal is generated as a function of the predetermined length of time, and an output signal is coupled to the bases of the two transistors to control their on/off states.

Brake installation for trailer trains

Abstract: 1. Carriage-train braking system comprising pressure-medium braking devices both on the traction engine and on the trailer, provided with an electric control for the traction engine brake and the trailer brake and with an electric pressure pick-up (16, 17) for differential pressure measurement and with a solenoid valve device (37) in the braking system of the trailer, the solenoid part of which can be controlled as a function of a signal, the magnitude of which is variable, of the electric pressure pick-up (16, 17) on the traction engine, characterised in that a pneumatic connection (reservoir line coupling head 23 and brakeline coupling head 24) for supplying a trailer reservoir (27) and for connecting the trailer brakeline to a trailer brake valve (26) is provided and that the trailer brakes are connected via a two-way valve (34) in parallel both to the solenoid valve device (37) and to the trailer brake valve (26).

Method of controlling automatic transmission shift pressure

Abstract: A method of selecting a desired transmission gear by controlling the duty cycle of a solenoid applying hydraulic pressure to one side of a transmission shift valve in relation to the hydraulic pressure applied to the other side.

Magnetic recording device

Abstract: PURPOSE:To save electric power and solve the problem of heat generation by using a self-holding type solenoid which is only fed with an instantaneous current at head loading, i.e. at attraction and return and requires no holding current. CONSTITUTION:The solenoid has a compression coiled spring 10 which generates restoring force and a permanent magnet 5 at the front part. A figure (a) shows a state before an attracting coil 1 is conducted. When the gap 13 between a movable iron core 3 and a fixed receptacle 9 is set larger than the gap 12 between the movable iron core 3 and a yoke 7, almost no attracting force is generated at the gap 13 by the magnetic force of the permanent magnet 5. A figure (b) shows an conductive state and the magnetic flux by the coil 1 is opposite to the magnetic flux of the permanent magnet 5 at the gap 12, so that all pieces of magnetic flux are attracted by the fixed receptacle 9. A figure (c) shows the nonconductive state of the coil 1 after the movable iron core 3 is attracted to the fixed receptacle 9 and the gap 13 at this time is zero, so the movable iron core 3 and fixed receptacle 9 are attracted continuously by the magnetic flux of the permanent magnet 5. A figure (d) shows a state when the conductive direction is made opposite, and the iron cre returns to its original position by the compressed coiled spring 10.