Showing papers on "Solenoid published in 1996"

The Forward muon detector of L3

Abstract: The forward-backward muon detector of the L3 experiment is presented. Intended to be used for LEP 200 physics, it consists of 96 self-calibrating drift chambers of a new design enclosing the magnet pole pieces of the L3 solenoid. The pole pieces are toroidally magnetized to form two independent analyzing spectrometers. A novel trigger is provided by resistive plate counters attached to the drift chambers. Details about the design, construction and performance of the whole system are given together with results obtained during the 1995 running at LEP.

The Modeling and Simulation of a Proportional Solenoid Valve

Abstract: A nonlinear dynamic model of a high speed direct acting solenoid valve is presented. The valve consists of two subsystems ; a proportional solenoid and a spool assembly. These two subsystems are modeled separately. The solenoid is modeled as a nonlinear resistor/inductor combination, with inductance parameters that change with displacement and current. Empirical curve fitting techniques are used to model the magnetic characteristics of the solenoid, enabling both current and magnetic flux to be simulated. The spool assembly is modeled as a spring/mass/damper system. The inertia and damping effects of the armature are incorporated in the spool model. The solenoid model is used to estimate the spool force in order to obtain a suitable damping coefficient value. The model accurately predicts both the dynamic and steady-state response of the valve to voltage inputs. Simulated voltage, current, and displacement results are presented, which agree well with experimental results.

Method for sweeping charged particles out of an isochronous cyclotron, and device therefor

Abstract: A method for sweeping a charged particle beam out of an isochronous cyclotron (1) comprising a solenoid forming a magnetic circuit that includes at least a number of sectors (3, 3') known as 'ridges' where the air-gap is reduced, and separated by sector-shaped spaces (4) known as 'valleys' where the air-gap is larger. According to the sweeping method, the particle beam is swept without using a sweeping device as the magnetic field has a special arrangement produced by designing the solenoid air-gap at the ridges (3, 3') of the isochronous cyclotron in such a way that the aspect ratio between the solenoid air-gap at the ridges in the region of the maximum radius, and the radius gain per turn of the particles accelerated by the cyclotron at said radius is less than 20.

Method for locating an inaccessible object having a magnetic field generating solenoid

Abstract: In order to locate an inaccessible object, such as an underground boring tool (30), a solenoid (10) on or in the tool generates a magnetic field which is detected at two measuring locations (20, 21). Information relating to the relationship between the axial and radial components of the field from the solenoid (10) are stored, and comparison of the measured values of the axial and radial components at the measurement locations (20, 21) enables the direction of the solenoid (10) from the measurement locations (20, 21) to be determined. The known attenuation of the magnetic field from the solenoid (10) enables the distance between the solenoid (10) and the measurement locations to be determined from the absolute value of the field at the measurement locations (20, 21) and the direction to the solenoid (10). The present invention thus makes use of the fact that there is a known relationship between the axial and radial fields of the solenoid (10) at any point in the plane containing the solenoid and the line joining the measurement location to the solenoid. A tilt sensor may be provided to indicate if the axis of the solenoid is not horizontal, to enable axial radial directions to be determined.

High latent refrigerant control circuit for air conditioning system

Abstract: A high latent cooling control assembly for a compression-expansion air conditioning system employs a subcooler coil (44) disposed in the leaving air side of the indoor air evaporator coil (22). A liquid line branch (42) supplies condensed liquid refrigerant from the condenser (16) to the subcooler coil (44), and a flow restrictor (48), which can be a TXV, drops the sub-cooled liquid pressure before the refrigerant reaches the expansion device (20) associated with the evaporator coil (22). A bypass line (50) connects the condenser (16) to the expansion device (20), and has a liquid line solenoid valve (32) that is humidistat actuated. When dehumidification is called for, the solenoid is closed and refrigerant flows through the subcooler coil (44). When the humidistat is satisfied, the solenoid opens and the refrigerant path bypasses the subcooler coil (44). The high latent subcooler assembly (40) can be field-installed or retrofitted onto an existing air conditioner.

Proportional variable force solenoid control valve

Abstract: A proportional variable force solenoid valve comprises a non-magnetic housing having a solenoid and a permanent magnet armature movable by the solenoid in response to current applied to the solenoid, a coil compression spring for biasing the armature in a direction to establish a valve fluid pressure response to solenoid current, and a valve housing closure engaging the spring and permanently deformed to position the closure relative to the spring in a manner to adjust the valve response. The size of the valve is reduced by providing a permanent magnet armature of reduced length having a flat outermost axial end which is engaged by the spring. A plate spring retainer is disposed on the flat axial end of the permanent magnet armature and is received with clearance in an enlarged longitudinal bore region of the solenoid coil bobbin.

Ground fault circuit interrupter

Abstract: A ground fault circuit interrupter (GFCI) interrupts the flow of current through a pair of lines extending between a source of power and a load. The GFCI includes a circuit breaker having a switch located in one of the pair of lines. The switch has a first position in which the source of power in its associated line is not connected to the load and a second position in which the source of power in its associated line is connected to the load. A relay circuit is coupled to the switch for selectively positioning the switch in either the first or second position. The relay circuit includes a solenoid which operates in either an energized or a de-energized state. When energized, the solenoid positions the switch in its second position and when de-energized, the solenoid positions the switch in its first position. The GFCI also includes a booster circuit for selectively supplying a first voltage through the switch and to the solenoid which is sufficient to cause the solenoid to switch from its de-energized state to its energized state. A power supply circuit supplies a second voltage to the solenoid which is less than the first voltage. The second voltage is sufficient to maintain the solenoid in its energized state after being initially energized by the first voltage but is insufficient to switch the solenoid from its de-energized state to its energized state. A latch circuit operable in first and second bi-stable states allows the solenoid to switch from its de-energized state to its energized state and remain in its energized state when in its first bi-stable state and allowing solenoid to switch from its energized state to its de-energized state and remain in its de-energized state when in its second bi-stable state. A fault detecting circuit detects the presence of a fault condition in at least one of the lines extending between the power and the load and causes the latch circuit to latch in its second bi-stable state upon detection of the fault condition.

Pulse width modulated solenoid driver controller

Abstract: Electronic drive circuitry for a solenoid that utilizes a pulse width modulation scheme is disclosed. The solenoid is connected in series with a transistor and a sense resistor. The voltage across the sense resistor is compared to a reference value to determine if an over-current condition exists within the solenoid. The circuitry operates on a repetitive time window scheme in which current is allowed to flow through the solenoid at the beginning of each time window, regardless of whether an over-current condition exists. If an over-current condition was detected at any time during the time window, then the current will be shut off to the solenoid during the next time window after the initial portion of that window. Conversely, if no over-current condition was detected during a time window, current will be allowed to flow during the entire duration of the next time window. Wraparound circuitry is also provided for sensing an open-coil condition during a latter portion of one of the time windows after a plurality of such windows has elapsed.

Electro-hydraulic control system in a power transmission

Abstract: Power transmissions incorporate gear ratios including a plurality of forward ratios, a neutral condition and at least one reverse ratio. The establishment of each ratio is controlled by selectively engageable hydraulically operated friction devices, such as clutches and brakes. The interchange between forward ratios is controlled by the interchange of at least one friction device. The control elements to accomplish the establishment and interchange of the ratios include a pressure source, shift valve, solenoid control valves and pressure control valves. The solenoid valves are electrically actuated and the hydraulic portion of the control includes elements that permit continued operation of the transmission in selected ratios in the event of electrical discontinuance. Also provided within the hydraulic control is a pressure knockdown or pressure reducing valve element which operates with one of the shift valves to establish a maximum pressure level in the forward ratios that is less than the maximum pressure level in the reverse ratio.

Solenoid and solenoid valve

Abstract: A solenoid comprising a solenoid coil (1) having a longitudinal hole (11c) made at the center of a bobbin (11) made of a non-magnetic material and a coil winding (12) wound round the peripheral wall (11d) of the bobbin (11), a yoke (2) comprising a peripheral side plate (21), an upper end plate (22) and a lower end plate (23) all for covering the outer peripheral surface and both end surfaces of the solenoid coil (1), a pole core (16) disposed at one end of the longitudinal hole (11c) and a plunger (15) fitted slidably into the other end of the longitudinal hole (11c). The solenoid further comprises a protrusion member (24) for forming an irregular magnetic field, formed integrally at the center of the yoke (2), and a recess (11f) for fitting the protrusion member (24) from the end surface of the peripheral wall (11d) of the bobbin (11), formed in the peripheral wall (11d). A diaphragm (3) of a solenoid valve for opening and closing a main valve port (63), opened and closed by the movement of the plunger (15) operates at a constant stroke above a predetermined feed water pressure and at a stroke proportional to the water drainage pressure below the predetermined feed water pressure.

Solenoid injector driver circuit

Abstract: A solenoid driver circuit is controlled by an electronic control module ("ECM") and eliminates many components required for a high voltage power supply required by the prior art. The solenoid driver circuit includes a high voltage select switch, a select switch and a modulation switch that are controlled by the ECM. The ECM causes the switches to be opened and closed so that the back EMF created by the solenoid coil when the modulation switch is opened can be recaptured by charging a capacitor. That energy can then be used to energize the solenoid coil.

Gasketing and bleed means for an electrically controlled faucet assembly

Abstract: An electrically controlled faucet is disclosed which is operable by pushing a button or placing hands within the operating range of a sensor. The faucet is mounted to a sink deck or like surface using specially configured gasket means which insure against slippage of the faucet on the deck. The gasketing means provide special channels through which electrical operating wires can be securely passed from the faucet to operating means below the sink deck. These operating means include a solenoid valve that controls fluid flow through the faucet and a temperature control valve fluidly linked to the solenoid valve. Solenoid disabling pressure buildup in the line linking the temperature control valve and solenoid is bled through special bleed means in the temperature control valve inlets.

Solenoid coil positioning assembly

Abstract: A solenoid actuated valve includes a first subassembly that carries a coil having its terminal pins attached to a structure such as a circuit board or lead frame. A second subassembly is provided for mating with the first subassembly and carries the valve body. The first subassembly has a solenoid spool including the coil, and a case surrounding the spool. An end plate is suitably locked to the case. A bias spring is provided between the spool and the end of the case. The spool assembly is designed to be freely floating both radially and axially within the coil case and end plate, as restricted by the bias spring. This permits proper location of the coil case to the hydraulic valve body assembly.

Simulation of plasma flow in toroidal solenoid filters

Abstract: An improved drift approximation model with an added radial electrostatic field has been successfully developed. Our model provides a computationally efficient way of quantitatively describing the plasma motion and predicting the plasma behavior in the toroidal solenoid in a filtered cathodic vacuum arc (FCVA) system. Storer's (1989) experimental results have been successfully simulated by this model. A good quantitative fit is obtained for our simulation results to the measured ion currents versus distance along the torus for various B field strengths, the attenuation length, and the wall current. The model describes the change of plasma density along the torus and provides the value of the electron-ion collision frequency at various conditions. The effect of the magnetic field and radial electric field on the plasma transportation can be assessed by the simulation and various plasma parameters can be determined. It is found that the radial electric field confines the 3-directional drift of the ions and is one of the most important parameters in determining the ion throughput. For any given B field strength and plasma parameters, there is a peak ion output corresponding to an optimal potential difference which can be obtained by the simulation. Over three times more ion output can be achieved when the torus wall is appropriately biased.

Solenoid valve for flow rate control

Abstract: A solenoid valve is disclosed and includes a solenoid, a plunger made of a magnetic material, and a yoke receiving the plunger therein such that the plunger may be moved by the magnetic field produced by the solenoid. A valve element is connected to the plunger for controlling the rate of flow through the solenoid valve. A permanent magnet is disposed in a desired position outside the yoke. The magnetic flux of the magnetic field of the permanent magnet is effectively used for damping the oscillation of the plunger to thereby achieve excellent controllability of the valve.

Solenoid valve and method for its manufacture

Abstract: A solenoid valve has a solenoid including a push rod. The solenoid has a central axis along which the push rod is displaceable. A valve member with a piston is provided, and the valve member and solenoid are enclosed in a casing. The solenoid and the valve member are connected to one another before being mounted in the casing such that the solenoid and the valve member are movable relative to one another in a direction perpendicular to the central axis.

Energy efficient control circuit for solenoid actuated locking device

Abstract: The present invention provides a driver circuit for energizing a solenoid actuated locking device. The circuit is adapted to include a microprocessor, a battery power supply, a boosting circuit and an energy storage circuit. The battery voltage is stepped up by the boosting circuit and the stepped up voltage is stored in the energy storage circuit. A solenoid driver circuit including a plurality of transistors arranged in an H-bridge configuration supply energy from the storage circuit to the solenoid under control of the microprocessor.

Building exterior fire prevention system

Abstract: A new Building Exterior Fire Prevention System for preventing bush and forest fires from engulfing a building by automatically soaking the building with water after a fire has been detected. The inventive device includes a central processing unit (CPU), a plurality of heat sensors, a solenoid powered control valve connected to a water main, a distribution pipe connected to the control valve and a plurality of sprinklers connected to the distribution pipe. The sprinklers direct water towards the building and towards the ground surrounding the building.

Control system for two opposed solenoid-type electromagnetic valve

Abstract: A control system for an electromagnetic valve having a valve element, a pair of solenoids opposed to each other and disposed to drive the valve element in respective directions opposite to each other and between a first extreme position and a second extreme position, and a spring interposed between the solenoids, for biasing the valve element toward a neutral position intermediate between the first and second extreme positions. The solenoids are controlled such that when the valve element is to start moving from one of the first and second extreme positions toward the other extreme position, energization of a corresponding one of the solenoids is terminated, and energization of the other solenoid is started when a predetermined delay time period elapses from the termination of the corresponding one solenoid. The solenoids are also controlled such that they are both energized over a predetermined lap time period during movement of the valve element from one of the first and second extreme positions toward the other extreme position.

Wireless residential door unlatch system

Abstract: Described is a preferred wireless system for unlatching the door of a residence. The system includes a solenoid/strike plate assembly controlled by a receiver unit which in turn is controlled by RF or other electromagnetic signals. The preferred system is readily retrofit into existing residential structures with a single bore into the door jamb into which the solenoid/strike plate assembly is mounted, and includes a minimum of moving parts.

Method and apparatus for controlling and detecting the position of a solenoid-operated valve element

Abstract: A method and apparatus for controlling a solenoid-operated valve element are provided. The valve element is movable between first and second end positions, and is urgable toward the first end position by magnetic attraction caused by activation of the solenoid and is normally urged toward the second end position. The method further enables detection of the time at which the valve element returns to the second end position from the first end position after deactivation of the solenoid. The method includes activating the solenoid by sending current from a current source through the solenoid to urge the valve element to the first end position, deactivating the solenoid by disconnecting the solenoid from the current source so that the valve element is urged toward the second end position, reconnecting the second end of the solenoid to the second pole of the current source a predetermined time after the solenoid is deactivated such that remaining energy in the solenoid generates a measuring current, and measuring the measuring current to detect a first predetermined characteristic change in the measuring current which occurs when the valve element has returned to the second end position.

Hydraulic and electric powered parking brake system

Abstract: The hydraulic and electric powered parking brake system (10) comprises a redundant or simultaneous operation of the system (10) to meet Federal Safety Standards. A dash mounted control knob (24) operates a hydraulic brake application mechanism (20) which transmits a hydraulic pressure to a hydraulically operated pilot piston (70). The control knob (24) also operates a switch (30) to send an electrical signal to an electrical control unit (100) which sends an electrical signal to a solenoid (80). The solenoid (80) and hydraulic pilot piston (70) can be operated, independently or simultaneously, to displace a control valve (60) located within a parking actuator assembly (114) and effect the release of hydraulic pressure from spring apply and hydraulic release actuators (16, 90) connected to vehicle brakes (18). The hydraulic fluid is released past the control valve (60) and to a reservoir (52). When the parking brake knob (24) is returned to an at-rest position, either the solenoid (80) or the hydraulic pilot piston (70), independently or simultaneously, can be operated to effect closing of the control valve (60) and actuation of a motor pump (50) which transmits fluid pressure to the spring apply and hydraulic release actuators (16, 90) so that the actuators will release the vehicle brakes (18) connected therewith.

Construction of ITER common test facility for CS model coil

Abstract: Japan Atomic Energy Research Institute is constructing the International Thermonuclear Experimental Reactor common test facility for the Central Solenoid Model Coil which is around 180 tons, a forced-flow cooled magnet with the maximum pulsed operation of 2 T/s and generates the rated magnetic field of 13 T at 48 kA with stored energy of 668 MJ. The test facility consists of a coil vacuum chamber, a cryogenic system with the 5-kW refrigerator and 500-g/s cryogenic pump, two pairs of 50-kA current leads, two DC power supplies (50 kA and 60 kA) and two JT-60 pulsed power supplies (50 kA, /spl plusmn/4.5 kV and /spl plusmn/40 kA, /spl plusmn/1.5 kV). The facility will be demonstrating the refrigeration and operation of a fusion pulsed magnet and the design and construction will accumulate experience towards the construction of ITER.

Integrated transmission control system

Abstract: An integrated solenoid circuit system for a motor vehicle transmission, and a method of forming the same. The system comprises a housing including a solenoid subhousing and a transmission range sensor (TRS) subhousing. The system also includes a solenoid sensor operatively located in the solenoid subhousing for sensing activation of transmission solenoids. The plurality of transmission sensors is operatively positioned in the transmission range sensor subhousing for communicating transmission states sensed by the solenoid sensor to the controller. A manifold is operatively mounted in the solenoid subhousing for energizing system components. A transmission sensor circuit operatively connects a plurality of transmission sensors to the manifold for selectively activating each of the plurality of transmission sensors in response to a sensed transmission state. The system integrates the transmission sensors, the manifold and the transmission sensor circuit into a single piece construction.

Positioning apparatus and method utilizing pwm control of a double-acting hydraulic cylinder

Abstract: A double-acting hydraulic cylinder is controlled by a pair of three-way solenoid valves respectively fluid connected to the two ends of the cylinder and energized in parallel with a continuous stream of pulse width modulated (PWM) pulses to create a mean effective fluid pressure balance at the cylinder ends that hold a desired position of a connected load and mean effective fluid pressure imbalances in the cylinder ends that produce variable rate load movement in either of two directions to a desired new position, all determined by the pulse duty cycle.

Brushless electric motor

Abstract: A solenoid-based propulsion system and methodology comprised of at least one multiple wire coil set solenoid that reversibly receives at least a portion of a magnetic object, wherein the wire coil sets of the solenoid are connected to the energizing control system that controls the alternate energizing of the wire coil sets; the adjustable dwell angle of the energizing; and provides for skip energizing. The electronic format of the energizing control system utilizes an electronic timer to establish the frequency at which the alternate energization occurs to propel the magnetic object in a reciprocal motion. The energizing control system in a payload delivery system embodiment of the invention helps converts the kinetic energy stored in the reciprocal motion of the magnetic object into a movement propelling the magnetic object completely and unilaterally out of the invention.

Method and apparatus for preventing coil induced delay in a automatic transfer switch

Abstract: An automatic transfer switch for transferring a load between a normal power source and an alternate power source has a control circuit which senses the movement of the plunger of the switch-actuating solenoid into a position proximate the plunger stop or pole piece and then turns off power to the coil current so that the plunger can be restored to its rest position as the inertia of the switch enables completion of the transfer. Upon interruption of voltage to the coil, the coil is switched in series with a resistance which rapidly dissipates the residual current generated by the collapsing field within the coil to alleviate the braking effect of the residual coil current on the solenoid plunger.

Inductive/MR composite type thin-film magnetic head

Abstract: An inductive/MR composite type thin film magnetic head which realizes high speed, high density recording while at the same time preventing the occurrence of read-out error by reducing NLTS. In one embodiment an inductive/MR composite type thin-film magnetic head is equipped with [a] an inductive head used for writing in which a magnetic gap layer, a conductive coil and insulating layers are laminated between upper and lower magnetic films, and [b] a magnetic resistance (MR) head used for read-out consisting of an MR element sandwiched between an upper shield which also serves as the aforementioned lower magnetic film, and a lower shield, the aforementioned conductive coil is formed in the shape of a solenoid which is wrapped around the aforementioned upper magnetic film by forming a lower coil part consisting of numerous segments on the surface of the first insulating layer, and then forming an upper coil part consisting of numerous segments from a point above a second insulating layer, upper magnetic film and third insulating layer laminated on the surface of the lower coil part, so that the respective end portions of the segments of the upper coil part are alternately connected with the respective end portions of the segments of the lower coil part.

Target and collection optimization for muon colliders

Abstract: To achieve adequate luminosity in a muon collider it is necessary to produce and collect large numbers of muons. The basic method used in this paper follows closely a proposed scheme which starts with a proton beam impinging on a thick target ({approximately} one interaction length) followed by a long solenoid which collects muons resulting mainly from pion decay. Production and collection of pions and their decay muons must be optimized while keeping in mind limitations of target integrity and of the technology of magnets and cavities. Results of extensive simulations for 8 GeV protons on various targets and with various collection schemes are reported. Besides muon yields results include-energy deposition in target and solenoid to address cooling requirements for these systems. Target composition, diameter, and length are varied in this study as well as the configuration and field strengths of the solenoid channel. A curved solenoid field is introduced to separate positive and negative pions within a few meters of the target. This permits each to be placed in separate RF buckets for acceleration which effectively doubles the number of muons per bunch available for collisions and increases the luminosity fourfold.