Showing papers on "Solenoid published in 1974"

Magnetic field generation apparatus

Abstract: A device for generating an easily accessible, substantially uniform and parallel magnetic field A number of identical solenoid posts are arranged symmetrically about a central axis and secured by corresponding ends to a pair of end-plates of magnetic material, to form an open, cagelike structure Equal magnetomotive forces are applied by separate windings on each post, the resulting magnetic field in the space between the endplates being substantially uniform and parallel to the axis, any non-axial flux components within the structure tending to cancel each other

Pulse width modulation control for valves

Abstract: A control circuit for a fluid controller such as a solenoid driven valve. A pulse output system operating at a fixed or variable frequency, with pulse width varying as a function of error signal. An integrator for integrating the error signal and providing an input to a threshold trigger circuit, and a multivibrator for periodically grounding the integrator output.

Exposure control system

Abstract: A system for controlling the closing of a camera shutter includes photosensitive means for detecting the available light level in the field of view of the camera to provide an output control signal a predetermined time after initiation of shutter closure dependent on the detected available light level. The power supply for the system includes a bidirectional linear magnetic generator which includes a spring drive which is mechanically loaded and unloaded by the film advance mechanism of the camera to power the exposure control circuitry. A solenoid, such as a rotary solenoid or linear solenoid magnetically latches the shutter in the open position during exposure until the solenoid coil is energized at the completion of the required exposure time to neutralize the magnetic flux in the magnetic stator of the solenoid, overcoming the magnetic latch and, due to a spring, thereafter biasing the armature to a second position which, through the mechanical linkage of the camera, closes the shutter.

Auto anti-theft device

Abstract: A solenoid-operated valve is disposed in the fuel line of an automobile to interrupt the fuel flow to the carburetor when the solenoid is deenergized. The solenoid operated valve is maintained in its fuel-open position only when both the automobile ignition switch is closed and a supplementary concealed switch is closed. The circuitry for operating the valve may include either a relay or an electronic device. An indicator light is illuminated during the fuel-closed position of the solenoid operated valve as a reminder that both switches must be operated to permit vehicle movement.

Magnetohydrodynamic behavior of a laser‐heated solenoid

Abstract: The problem of laser‐induced heating and radial expansion of a low‐density plasma in a solenoidal magnetic field has been examined by means of a Lagrangian computer code incorporating an exact solution of the relevant MHD equations plus thermal conduction. It is shown that for long‐term heating with a realistic range of laser power and magnetic field strength, the resulting radial temperature and density profiles can be closely approximated by a quasistatic solution of these equations.

Automatic drink dispenser

Abstract: An automatic drink dispenser for filling cups with liquid when placed in receiving position on a support platform and including a solenoid controlled valve for dispensing liquid into said cups comprises at least one contact member positioned to make contact with the liquid dispensed into said cup in said receiving position when the liquid reaches a predetermined level therein and means electrically interconnecting said contact member and said solenoid control valve for controlling said valve to stop the flow of liquid when the liquid reaches a predetermined level in the cup.

Electrically operated rotational actuator with failsafe disengagement

Abstract: A rotational actuator including an electric motor and gear reduction means. The gear reduction is at least partly provided by a planetary arrangement which transmits the rotational motion or permits its output shaft to "free-wheel" as a function of engagement or disengagement of a solenoid operated device for restraining the rotation of the ring gear of a planetary subassembly or permitting its free rotation, respectively. The output shaft is thus readily manually overridden when the solenoid is not energized. An optional overcenter resilient means (compression spring) provides for return of the output shaft to a first or second extreme position when the solenoid is deenergized.

Circuitry for controlling the response time of electromagnetic devices with a solenoid

Abstract: A method for controlling the response time of an electromechanical device having an actuating solenoid comprising: applying three reference voltages from three reference voltage sources in a predetermined order to a voltage and current amplifier which drives the solenoid, generating from the three reference voltages three corresponding currents through the solenoid, the three currents being a premagnetization current, a maximum activation current of the solenoid and a deactivation current of the solenoid.

Lighted hole assembly and ball projector for playboard

Abstract: A playboard for a pin ball machine having a ball-receptive hole, the bottom of which is formed by a translucent wafer having a diametrical slot. A trigger member underlies the wafer having a pair of upstanding parallel fins which extend upwardly through the slot adjacent the edges thereof, the member being yieldingly mounted so that the fins depress when a ball falls into the hole. A switch responsive to the movement of the trigger member energizes a solenoid which actuates an ejection finger centered between the fins of the trigger member for prompt ejection of the ball. A source of light is provided under the hole for illuminating the wafer and trigger member including the fins. At least a portion of the surfaces are faceted to provide bright jewel-like illumination within the hole.

Methods of finding the parameters of ideal current loops for computer simulation of magnetic fields

Abstract: Methods are described for finding the position, radius, and strength of ideal current loops to represent the magnetic field of 1) a partially immersed convergent electron gun, 2) a short solenoid, using the Helmholtz concept extended to triplets and quadruplets, and 3) a periodic permanent magnet (P.P.M.) focusing stack for a TWT. The parameters of the coils then constitute a complete description of the magnetic field with no paraxial approximation.

Material dispenser control circuit with false trigger prevention

Abstract: A control system for turning on and off apparatus which discharges material onto objects moving on a conveyor past an article sensing and material dispensing station. An article sensor, including an incandescent lamp and a phototransducer spaced on opposite sides of a conveyor, senses movement of an article beneath a material dispensing valve as the article interrupts a light beam projecting across the conveyor from the lamp to the phototransducer. A threshold detecting circuit, including an operational amplifier and a single-shot, responds to the change in light intensity on the phototransducer occasioned by interruption of the light beam to energize a solenoid which controls operation of the material dispensing valve. A power supply including a full-wave rectifier and a smoothing capacitor provide power for the circuit components. A switch in the energization path of the solenoid, which is opened when the main ON/OFF power switch located between the rectifier and a conventional 60Hz source is opened, prevents discharge of energy from the smoothing capacitor to the solenoid to actuate the dispensing valve when the threshold detector faslely cycles as the incident light on the photocell decreases when the lamp is de-energized by open-circuiting the ON/OFF switch. A capacitor connected between the phototransducer input line to the operational amplifier and the power supply alters the potential of the reference input to the operational amplifier such that the signal output from the phototransducer to the operational amplifier temporarily existing after the ON/OFF switch has been closed and prior to build-up of the incandescent lamp intensity to its normal level does not falsely trigger the operational amplifier and in turn cycle the solenoid and material dispensing valve.

Combination smoke and heat detector alarm

Abstract: A combination smoke and heat detector alarm including a self contained stored energy source in the form of a cylinder of compressed gas. A T-fitting connects to the cylinder and feeds separate conduit systems leading to individual sounding devices. A fusible element is interposed in one of the conduit systems to automatically permit transfer of the compressed gas to a first sounding device upon the presence of elevated temperatures. A solenoid operated switch is interposed in the other conduit system to normally prevent the flow of gas. The solenoid is responsive to a smoke detector and is wired to open the solenoid valve upon sensing the presence of a predetermined concentration of smoke.

High speed solenoid employing multiple springs

Abstract: A high speed solenoid assembly especially adapted for use in impact printers of the dot matrix type The solenoid coil, when energized, drives the solenoid armature and a print wire connected thereto for impact against an inked ribbon and paper document to form a dot upon the paper document The armature is initially driven against the biasing force of a "weak" spring to facilitate rapid acceleration to impact velocity Just before the print wire strikes the inked ribbon and paper document, the armature comes under the influence of a "kicker" spring having a greater spring force and which is flexed by the moving armature which serves to return the armature to the non-impact position at a more rapid rate when the solenoid coil is deenergized The use of a headed armature with a depression along its rear surface serves to significantly reduce armature "bounce" The assembly significantly reduces elapsed time between movement of the armature and print wire from the rest position to the impact position and return of the armature to the rest position enabling significantly increased printing speeds

Solenoid actuator for high pressure valve

Abstract: Some solenoid operated valves have their plungers and plunger guides exposed to the fluid medium that the valve controls. Such solenoids are commonly referred to as ''''wet solenoids'''', though the medium controlled may be either liquid or dry gas. When the medium control is at high pressure, of the order of 6,000 pounds per square inch or higher, the plunger guide must be constructed with hoop strength sufficient to withstand this pressure. This invention provides a valve construction with the plunger guide of thin wall section for a portion of its length, so that it becomes magnetically saturated to concentrate flux in the plunger, and with special provisions for preventing the high pressure fluid from breaking the thin wall. The plunger guide, when there is no fluid pressure in the valve, is mechanically loaded by a force exerted in a direction opposite to the main thrust of the high pressure medium.

Recording arm safety lifter

Abstract: There is disclosed a disc type magnetic recording and playing system wherein a recording arm tracks over concentric circular tracks in a flexible magnetic disc. There is also disclosed apparatus for swinging the recording arm into position with the record/playback transducer centered within a given track, and a stepping motor for stepping the transducer from track to track. A safety lifting device is provided for prevention of excessive wear of any one track. The safety lifting device is under the control of a solenoid which in turn is energized through a timer. When any of several operating controls are activated the timer is set and the solenoid is energized. After a predetermined period of time, the timer deenergizes the solenoid, and the arm is raised automatically. Raising of the arm is accomplished by a spring which works against the solenoid so that there is always a positive arm lifting moment which in the absence of an energizing current to the solenoid, raises the arm. Thus "fail safe" operation is provided.

Retarder control device

Abstract: A retarder control device for a vehicle with an oil-cooled multi-plate disc brake which has solenoid and hand brake valves assembled in parallel with a pneumatic line. A check valve is provided at the pneumatic pressure line for checking oil flow from the solenoid and hand brake valves, and thus the rear brake is manually and automatically operated.

Solenoid driving means

Abstract: Apparatus for sequentially energizing and maintaining a pulrality of solenoids in operated condition for a predetermined period of time includes electro-optical distributive means for sequentially applying triggering pulses circuits, a plurality of solenoid operating amplifiers, each of said circuits including two operational amplifiers, one of which is included in a circuit for providing a solenoid energizing pulse, and the other of which is included in a circuit for providing a solenoid holding pulse.

Shift locking device for vehicle manual transmission

Abstract: Unless a driver wears a seat belt a solenoid plunger engages a notch in the striking rod operated by a manual shift lever locking it in neutral.

Three axis coil magnetic minesweeping system

Abstract: A magnetic influence minesweeping system and a method are disclosed whereinhree large area air core solenoid coils are arranged with their planes in mutually orthogonal relation. A battery power supply and alternating current pulse generator are utilized to successively energize each coil and generate three magnetic fields having mutually perpendicular principal axes.

Automatic choke assembly for small engines

Abstract: An automatic choke for an internal combustion engine includes a rotary solenoid which is energized when the engine is cranked by the starter motor. During starting, the solenoid rotates a choke valve to its starting position in which choking is applied, and a bimetallic temperature responsive spring coupling the solenoid to the choke valve adjusts the amount of choking in response to the ambient temperature. A stop element limits the range over which the bimetallic spring adjusts the position of the choke valve.

Dynamically compensated exposure control system

Abstract: An exposure control system for photographic apparatus of a variety utilizing a solenoid actuated exposure mechanism drive. Consistent dynamic performance for the system is achieved through an arrangement wherein the solenoid is coupled to be operated only against the substantially constant retarding force of a spring, while exposure mechanism movement, with attendant massaccelerative characteristics, is provided by isolated spring drives.

Inlet and outlet valve control arrangement - uses DC error signal with superimposed triangular waveform to minimise operating error (BE020676)

Abstract: The precise control of pressure within a container is achieved by continuous pulsing of inlet and outlet solenoid valves operating about average value levels. A comparator (1) operates upon a preset reference level signal (Vc) and a feedback signal from a pressure transducer (2). A signal generator (3) produces a triangular wave output of constant frequency that is amplified (4) before transmission to an adder circuit (5). The adder circuit output is of variable d.c. level with the triangular wave from superimposed and is used to drive inlet solenoid valves (EVA, EVA') and outlet valves (EVE, EVE') coupled to the pressure container (C). In operation two valves (EVA, EVE) are set to respond to a higher level than the other valves to operate when large erras exist.

Choke control system for carburetors

Abstract: A mechanism is provided whereby the opening of an automatic choke valve is controlled by means of pressure in a diaphragm chamber with the chamber being selectively communicated with a vacuum pickup tube or an atmospheric pressure pickup tube through operation of a solenoid controlled valve. A switch actuatable in response to vehicle speed and another switch actuatable in response to engine temperature operate to selectively connect the solenoid controlled valve to a power source thereby to determine the operating mode of the valve.

Photographic copying arrangement with automatic diaphragm control

Abstract: A first and second diaphragm blade respectively are coupled to a first and second solenoid. The solenoids are intercoupled by gearing in such a manner that the first solenoid rotates in a direction opposite to the second solenoid. One solenoid is activated for closing the diaphragm, one for opening the diaphragm. The signals activating each solenoid are derived from a differential amplifier which compares a signal furnished by a photosensitive element to a reference signal signifying the desired exposure.

Automatic dog and cat feeder

Abstract: An animal feeder including a feed hopper and a timer actuated discharge means. The discharge means including a panel for closing the hopper held in place by a magnetic catch and released by a push type solenoid means.

Transmission locking device

Abstract: The selector lever in "N" is caught and locked by a notch of a plate moving in response to an actuated solenoid energized by failure of the driver to fasten his seat belt.

Toroidal solenoids with a space magnetic and a plane-geometry axis

Abstract: A study is made of the magnetic field of a solenoid formed by current-carrying loops, the plane of which is perpendicular to a helical line. Analytical expressions are derived for the scalar potential and the components of the magnetic field strength inside a straight solenoid with a dense winding. The toroidal case was investigated using a BESM-6 computer. The results are presented of an experimental study of the magnetic field of a rectilinear system with a helical magnetic axis. The paper discusses the possible design of a toroidal trap with the magnetic configuration in question.

The solenoid which gives the desired value of magnetic field for the smallest possible volume of conductor

Abstract: We derive the shape which a solenoid must have to give, for the smallest possible volume of conductor, the desired value of magnetic field at a point z0 on its axis. To get a somewhat more complete picture of the field produced by the solenoids of such shape we study its behavior away from point z0 in the case of the cylindrical ``frame'' of radius r0=2 cm and for a few values of the conductor volume.

Flat packaging of magnetic bubble devices

Abstract: This paper describes a new method of packaging of a bubble device using, "flat-faced-coil (FFC)" drive coils, which simplify bubble device construction and facilitate easy heat radiation from the coils. The construction of the bubble drive coils is very important, because it determines the bubble device assembly process and the thermal dissipation of the coils. The FFCs sandwich the bubble chips. On the other hand, solenoid coils usually wrap around the bubble chips. As the FFC creates no large obstacles, it is easy to remove bubble chips from the coils as required. There is also excellent accessibility when wiring from the bubble chips to the electronic circuits.