Abstract: A proportional solenoid, capable of linear motion, includes an electromagnetic valve device including a solenoid assembly having a mobile core, a push rod connecting the solenoid mobile core to a valve plunger, and a device operable to apply a controlled friction force to hold the mobile core in an intermediate position. The friction force applied by the friction device is greater than the motive forces generated by the solenoid.

Abstract: A water and/or air dispenser for snowmaking system includes water and/or air supplying ducts and is equipped with at least one valve (9) associated with an electric actuator (10), the actuator (10) being connected to an electric power source (12, 19) and associated with its own management unit (11) to ensure the operation of the valve (9) between the open and closed configurations thereof. The dispenser is associated with security elements able to cause the valve (9) to be positioned in a known security configuration, for example tightly closed, in case of voltage cut-off at the electric source (12, 19), the security elements being integrated and including a capacitor-type electric unit (16), connected to the electric power source and to the actuator (10), the capacitor unit being able to store, and then return, a quantity of energy necessary for complete actuation of the valve, to implement the security elements.

Abstract: A valve control apparatus including a stepping motor coupled to a valve and a motor control unit for controlling the stepping motor is provided. The motor control unit includes a motor control section for applying drive pulses to the pulse motor, a counting section for counting the number of drive pulses applied to the pulse motor, a voltage-drop detecting section for detecting a voltage drop of a drive power supply for the motor control section, and a writing section for writing a count from the counting section in a nonvolatile memory if the voltage-drop detecting section detects the voltage drop.

Abstract: An emergency shutdown system includes an emergency shutdown valve, a control line to carry a signal determinative of positioning of the emergency shutdown valve, a solenoid assembly coupled to the control line to effectuate the positioning of the emergency shutdown valve, and a junction device coupled to the control line and the solenoid assembly. In some embodiments, the junction device includes a switch, such as a relay, responsive to the signal to control whether the solenoid assembly is coupled to the control line and, therefore, energized.

Abstract: A valve locking device comprising an intermediate member (18) mountable between a valve body and valve actuator and securable to said valve body and/or actuator; a stem attachment member (20) attachable to and rotatable with a valve stem (14) and contained at least partially within said intermediate member, and an engagement member (22) movably located within said intermediate member for selective engagement with said stem attachment member; whereby in use, engagement between said engagement member and said stem attachment member prevents rotation of said stem attachment member, thus preventing rotation of said valve stem to operate the valve.

Abstract: In a device for restoring a throttle valve, which is for controlling combustion air of an internal combustion engine, into a definite limp-home air position, having a throttle valve shaft, which supports a drivable driver and is rotatably supported in a housing, and having a prestressed clamping spring, whose spring ends, by simultaneously embracing a housing catch and a driver catch on opposing catch surfaces, fix a limp-home air position of the throttle valve, from which the throttle valve can be moved through rotation of the driver , a compensation spring, which has a definite initial stress force directed counter to the spring force of the clamping spring, is disposed between one spring end of the clamping spring and a catch surface on one of the catches in order to produce a rotary play-free state of the driver in the limp-home air position.

Abstract: An electromagnetic actuator composed of: an armature movable along a linear path between first and second end positions; electromagnets positioned and operative for selectively moving the armature to either one of the first and second end positions; and a mechanical holding element operative in response to movement of the armature to either one of the end positions for holding the armature in the end position to which the armature has moved until an appropriate one of the electromagnets is operated to move the armature to the other one of the end positions.

Abstract: The invention relates to an electromagnetic valve having a passage therethrough and a closure member which is reciprocable between first and second positions in whoch the passage is openend and closed. An electromagnectic controllable actuator effects movement of the closure member against a spring force from the first position into the second position. The valve includes a retainer which retains the closure member in the second position. The retainer is formed by a piezoelectric bending element which locks the closure member positively in the second position.

Abstract: To provide for extremely short valve operating time periods, in the order of up to 10.sup.-5 seconds, for example, a valve element (3, 33, 53, 63, 73, 93) is slidable within a bore (2, 52), movable by a spring (10, 60) or by applied hydraulic pressure (P), and restrained from movement by an electrical positioning element (14, 44, 45, 94) which has a positioning movement transverse to the movement of the valve element, and which clamps the valve element in the bore, or an extending flap or strip (34) against a counter element, which may be another positioning element (45). Preferably, and for fast operation, the positioning element (14) is a stack or column (15) of piezoelectric disks (16) which, when energized, push a stem or bolt element (13) in clamping direction towards the valve stem; alternatively, (FIG. 6), the positioning element (94) can be a solenoid coil pushing the armature (93) thereof into clamping direction towards the valve stem.

Abstract: A gas supply pipe is provided with a terminal shutoff valve upstream of a heater, stove or the like. An automatic shutoff valve is provided to the gas pipe upstream of the terminal shutoff valve which automatically closes upon receipt of an electrical signal from an earthquake sensor, fire detector, gas leak detector or other sensor indicating a dangerous condition. A gas pressure sensor provided between the automatic shutoff valve and the terminal shutoff valve prevents the automatic shutoff valve from being manually reset unless the terminal shutoff valve is closed, thereby preventing an explosion which might result if gas were fed to the heater or stove with the pilot light extinguished.

Abstract: An electrically operated fail-safe valve actuator employs a spring which is wound to store energy during operation of the electric drive motor, an electric clutch operable to disengage the drive motor from the actuator output shaft in response to loss of power from the electrical supply whereby the spring drives the valve in the opposite direction.