Solenoid

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

Electrically controlled pressure relief valve system and method

Abstract: An electrically controlled, proportional, pressure relief valve (100/200) used to control the maximum allowable pressure in a hydraulic line (3), whose pressure is used to control, for example, the relative up-and-down positioning and speed of movement of a combine header (1) on an agricultural combine, in which the effective maximum pressure of the pilot valve of the relief valve is controlled by a solenoid (113/213). The distal tip of the armature (114/214) of the solenoid bears against a movement and force translating drive pin (112/212), which in turn bears against a ball (110; FIG. 2) or a poppet pin (210; FIG. 3). The effective maximum pressure permitted by the relief valve is linearly varied by the applied voltage/current to the solenoid coil (115/215). Such an arrangement allows the electrically controlled pressure relief valve to be easily interfaced and controlled by, for example, a computer (20) with a condition responsive input/output section (21), greatly expanding the possible applications for the pressure relief valve system of the invention. In the preferred application (FIG. 1 ), the movement of a ground contacting ski sled (22) carried by the combine ("C") is monitored by the computer, which then sends electrical signals to the pressure relief valve, which in response to the electrical signals controls the pressure level in the hydraulic line to the ram moving the combine header, determining its vertical position and the speed with which the header moves, as it goes from one vertical position to the other with respect to the ground.

Design and Tests of Prototype Hybrid Superconducting Fault Current Limiter With Fast Switch

Abstract: This paper deals with design and operating tests of prototype hybrid superconducting fault current limiter (SFCL) which is series connected non-inductive solenoid resistive coil and asymmetric non-inductively wound coils. The role of resistive SFCL is for reducing the fault current in the first swing. Moreover, resistive SFCL can reduce a load of dielectric strength in hybrid SFCL. Two kinds of high temperature superconductor (HTS) wires were used to fabricate asymmetric HTS coil. These HTS wires had different quench characteristics such as different critical current and n-value. Unbalanced current distribution between two HTS wires in the asymmetric HTS coil during the fault should occur. Thus, the asymmetric HTS coil generates impedance and repulsive force from magnetic flux. The finite element method was performed to calculate maximum repulsive force. From experimental tests and FEM simulation results, proper combination of HTS wires and configuration of asymmetric HTS coil with fast switch were determined to increase maximum repulsive force. Also, the prototype hybrid SFCL with fast switch was fabricated and performed.

Expansion valve for air conditioning system with proportional solenoid

Abstract: An expansion valve (10) for heat transfer systems such as an air conditioning system, includes a control element (20) for controlling the flow rate of working fluid through the valve. The control element has a stem member (28) and movable member (42) movable on the stem member. Openings (38) to an internal passage (30) in the stem member are regulated by positioning the movable member to achieve regulated flow rate of refrigerant material through the valve. The movable member of the control element is moved by a plunger (24) of a proportional solenoid (22). The proportional solenoid has a magnetic flux circuit including a low permeance isolation tube (62) surrounding the plunger, which enables removal of the coil (76) and frame (78) of the solenoid from the valve. The solenoid further includes a variable permeance flux washer (69) the flux through which varies with plunger position, which is disposed from a gap (82) which provides an area of magnetic saturation. The proportional solenoid produces force/displacement characteristics which enable precise control of the control element and accurate regulation of the refrigerant flow rate through the valve.

Driver alertness device

Abstract: A driver alertness device is disclosed. The device includes a timing counter that decrements from the time set towards zero. When the timer reaches zero, a solenoid is energized to urge the throttle to the idle position. A reset button is manually operable by the driver of the vehicle, a predetermined amount of time being added to the timer for each push of the reset button, and an on/off switch is accessible to the driver.