Solenoid

About: Solenoid is a research topic. Over the lifetime, 19278 publications have been published within this topic receiving 114721 citations.

Active control of simply supported plates with a magnetostrictive layer

Abstract: This paper deals with the damping characteristics obtained by using a distributed magnetostrictive layer, bonded to an aluminum plate for different boundary conditions and coil configurations. The magnetostrictive layer is used to induce the actuating force to control vibration in the plate, based on a negative velocity feedback control law. The control input is the current to the solenoid surrounding the plate. In several prior formulations in the literature, it has been assumed that the current through the coil is a function of axial distance. Even though this assumption is mathematically valid, a physical consideration of the problem does not allow such an assumption. In the present study, perhaps for the first time, a finite element formulation, physically consistent with the problem, has been developed. Vibration reduction in the plate by positioning the magnetostrictive layer and its current carrying actuating coil pair along the plate is investigated. Issues associated with control for different boundary condition are highlighted.

Valve operating system

Abstract: The system is particularly suitable for controlling a solenoid valve SV1 having two stable operating positions in accordance with programmed `on` and `off` periods set at a 24 hour timer 10. The valve typically in one position connects a gas supply to a regulator ensuring the latter then supplies gas at a higher pressure; and in the other position connects the regulator to atmosphere through a vent stack so that the regulator then supplies gas at a lower pressure. The system is powered by 3 volt batteries B1, B2 and has extremely lower current consumption giving a battery life of 5-6 years. The solenoid 18 is energised briefly by voltage pulses fed from a capacitor C5 via a reversing switch 16. Automatic battery voltage checking is incorporated.

Solenoid engagement sensing circuit

Abstract: In a disk memory library, picker arms, operated by a solenoid, are used to remove a selected disk from a library stack of disks and to place the disk in a reading/writing environment. The solenoid plunger's position is determined by noting its effect on a series resonant circuit that is formed with the coil inductance of the solenoid coil and a series capacitor. A function generator provides a triangular signal to the solenoid coil. An amplifier and peak detector are coupled to the coil to amplify and peak detect the voltage signal across the coil. A threshold detector, coupled to the output of the peak detector, is set to provide a digital output indicating when the solenoid's plunger is in or out. The function generator also provides a square wave that is synchronized to the triangle wave and is coupled to sample the output from the threshold detector. The change in the coil's inductance causes a phase shift in the triangle wave which further accentuates the voltage difference appearing across the coil. The output from the synchronous detector is used to determine when the plunger is in or out and, in turn, when the picker arms are extended or retracted.

Marker assembly for spray marking dot matrix characters and method of fabrication thereof

Abstract: A linear array of solenoid actuated marker valve assemblies is contained in a housing configured as a manifold which carries marker fluid as well as nebulizing air supplies and a solvent distributing valve for use in clearing the air passages. All valve assemblies are accessible from the front surface of the device for ease of maintenance and are assembled in a manner assuring uniform and consistent valve stem travel advantageously eliminating the need for valve stem travel adjustment. The control system utilized with the valve assemblies provides both for an enhanced current input rate to the windings of the solenoid driven components, as well as an efficient and effective turn-off clamping procedure. This form of actuation of the solenoids achieves dynamically efficient and rapid turn-off and turn-on to the extent that the size of dots formed by the assembly can be provided having a broader range of diameters and these diameters can be adjusted remotely by a simple impedance variation. The features of the invention permit the application of characters at substantially enhanced production line speeds.

Fail-safe ground fault receptacle circuit

Abstract: A fail-safe ground fault receptacle circuit includes a ground fault circuit interrupter inductively coupled to a load, directly coupled to one potential source terminal, and coupled by way of a series connected solenoid winding and contacts of a circuit breaker shunted by a series connected impedance and indicating lamp to another potential source terminal whereby manually closing the circuit breaker causes current flow through the solenoid winding shunting the indicator lamp and preventing activation thereof and excessive current flow through the solenoid winding opens the circuit breaker to cause current flow through and activation of the indicating lamp