A valve device has a valve housing (10), in which fluid ports (P, A, T) are provided and in which at least one valve piston (12, 14) can be moved longitudinally. The valve piston either separates at least two of the fluid ports (P, A, T) from one another or interconnects them as a function of its travel position. At least one latching device (16, 18) is provided for each valve piston (12, 14) for the detachable fastening of the respective valve pistons (12, 14) in one of its travel positions. Each latching device has at least one latching means (20), which can be brought into a latching position (22). As part of the respective latching devices (16, 18) for detachably fastening the respective valve pistons (12, 14), at least one control body (24) t can be moved independently of the respective valve pistons (12, 14), which control body is set up such that, in at least one blocking position, it prevents the relevant latching means (20) disposed in the latching position (22) from leaving the latching position (22) by blocking the latching means (20).

A valve device has a valve housing (10), in which fluid ports (P, A, T) are provided and in which at least one valve piston (12, 14) can be moved longitudinally. The valve piston either separates at least two of the fluid ports (P, A, T) from one another or interconnects them as a function of its travel position. At least one latching device (16, 18) is provided for each valve piston (12, 14) for the detachable fastening of the respective valve pistons (12, 14) in one of its travel positions. Each latching device has at least one latching means (20), which can be brought into a latching position (22). As part of the respective latching devices (16, 18) for detachably fastening the respective valve pistons (12, 14), at least one control body (24) t can be moved independently of the respective valve pistons (12, 14), which control body is set up such that, in at least one blocking position, it prevents the relevant latching means (20) disposed in the latching position (22) from leaving the latching position (22) by blocking the latching means (20).

In various implementations, an electronic actuator may be coupled to a valve to provide the ability to shut off anhydrous ammonia flow through the valve (e.g., in emergencies). The valve may be coupled to anhydrous ammonia tanks, such as nurse tanks and/or storage tanks. The electronic actuator may include a handle and a bracket. The handle and the bracket may include at least two attractive components that are magnetically attracted to each other upon application of an electric current and the valve may be open. When the electric current is cut, the attractive components of the handle and the bracket may not be magnetically attracted to each other and the valve may be shut off. A controller (e.g., a switch) may be coupled to the electronic actuator to allow control of the electric signal to the electronic actuator.

In various implementations, an electronic actuator may be coupled to a valve to provide the ability to shut off anhydrous ammonia flow through the valve (e.g., in emergencies). The valve may be coupled to anhydrous ammonia tanks, such as nurse tanks and/or storage tanks. The electronic actuator may include a handle and a bracket. The handle and the bracket may include at least two attractive components that are magnetically attracted to each other upon application of an electric current and the valve may be open. When the electric current is cut, the attractive components of the handle and the bracket may not be magnetically attracted to each other and the valve may be shut off. A controller (e.g., a switch) may be coupled to the electronic actuator to allow control of the electric signal to the electronic actuator.

A valve actuator for a valve has an electric motor which comprises a rotor and a stator, and further a magnetic detent brake with at least one detent magnet for holding the rotor in a detent position. The least one rotor magnet is arranged on the rotor and co-operates with the detent brake.

A valve actuator for a valve has an electric motor which comprises a rotor and a stator, and further a magnetic detent brake with at least one detent magnet for holding the rotor in a detent position. The least one rotor magnet is arranged on the rotor and co-operates with the detent brake.

A limit switch assembly, for a rising-stem valve having a stem with a diameter and a groove marking a desired stem position, includes an actuator arm having an inner end and an outer end. The inner end of the actuator arm forms a follower. A radius washer is mounted to the outer end of the actuator arm. An electrical switch has an operating lever and is mounted adjacent to the outer end of the actuating arm such that when the actuator arm is in an outward position the radius washer moves the operating lever, operating the electrical switch. When the actuator arm is in an inward position the radius washer does not move the operating lever and the electrical switch is not operated. A bias spring biases the actuating arm toward the inward position.

A limit switch assembly, for a rising-stem valve having a stem with a diameter and a groove marking a desired stem position, includes an actuator arm having an inner end and an outer end. The inner end of the actuator arm forms a follower. A radius washer is mounted to the outer end of the actuator arm. An electrical switch has an operating lever and is mounted adjacent to the outer end of the actuating arm such that when the actuator arm is in an outward position the radius washer moves the operating lever, operating the electrical switch. When the actuator arm is in an inward position the radius washer does not move the operating lever and the electrical switch is not operated. A bias spring biases the actuating arm toward the inward position.

A method and toolset capable of remotely moving a rotor of an implanted device in a first arcuate direction and detecting a first limit of travel, moving the rotor in a second, opposite direction and detecting a second limit of travel without altering the current performance setting of the implanted device, comparing the first and second limits of travel with known values for a plurality of selectable performance settings, and indicating the current performance setting of the implanted device.

A method and toolset capable of remotely moving a rotor of an implanted device in a first arcuate direction and detecting a first limit of travel, moving the rotor in a second, opposite direction and detecting a second limit of travel without altering the current performance setting of the implanted device, comparing the first and second limits of travel with known values for a plurality of selectable performance settings, and indicating the current performance setting of the implanted device.