초록 ▼

Actuator for a seat valve or a butterfly valve which is of the type that is normally closed (NC) or normally open (NO), and also has a cylinder and a piston being held in the normal position by a spring. The spring includes a closed space with a pressurized fluid, and the actuator further has at lea

Actuator for a seat valve or a butterfly valve which is of the type that is normally closed (NC) or normally open (NO), and also has a cylinder and a piston being held in the normal position by a spring. The spring includes a closed space with a pressurized fluid, and the actuator further has at least a top unit, with two or more connections for a pressurized fluid. The actuator is with one of the connections in the top unit that is connected to the inside of the cylinder through one or more openings at one end of the cylinder and another connection is connected to the inside of the cylinder through one or more openings at the other end of the cylinder. The top unit is designed to allow the connections to be interchanged by changing the position of the top unit, e.g. by turning the top unit 180 degrees around an axis corresponding to or parallel to the axis of the piston and cylinder.

대표청구항 ▼

1. Actuator for activating opening or closing of a valve, where the actuator is of a type that is normally closed or normally open, and also contains a cylinder and a piston, said piston being held in the normal position in the cylinder by a spring,wherein said spring acting on the piston in the cyl

1. Actuator for activating opening or closing of a valve, where the actuator is of a type that is normally closed or normally open, and also contains a cylinder and a piston, said piston being held in the normal position in the cylinder by a spring,wherein said spring acting on the piston in the cylinder consists of a closed space with a pressurised fluid,the actuator further comprises at least one top unit with two or more connections for the pressurised fluid, the top unit being rotatably mounted on the cylinder, one of said connections for pressurised fluid in the top unit is connected to the closed space inside said cylinder through an opening of the cylinder and another of said connections for pressurised fluid in the top unit is connected to the closed space inside said cylinder through another opening of said cylinder,the top unit being configured to rotate relative to the cylinder to change a position of the top unit relative to the cylinder to allow the connections to be interchanged. 2. Actuator for activating a valve according to claim 1, wherein the cylinder includes a cylinder wall and a plurality of internal fluid channels along the cylinder wall, where the internal channels near one end of the cylinder are open to the inside of said cylinder and at the other end are in connection with a connection for pressurised fluid. 3. Actuator for activating a valve according to claim 1, wherein the cylinder is closed at least at one end, an outer end face of the cylinder is provided with at least two holes, where the top unit is provided with corresponding holes and where sealing between the cylinder's outer end face and the top unit is accomplished with a static seal arranged around the holes. 4. Actuator for activating a valve according to claim 3, wherein the static seal is an O-ring arranged around the holes. 5. Actuator for activating a valve according to claim 1, wherein the cylinder is closed at least at one end, an outer end face of the cylinder is provided with two elongated recesses, where the top unit is provided with holes arranged to correspond to said recesses and where sealing between the cylinders outer end face and the top unit is accomplished with a static seal arranged around the elongated recesses. 6. Actuator for activating a valve according to any one of claim 3 and claim 5, wherein the outer end face of the cylinder is provided with one or more symmetrically arranged threaded holes for fixing the top unit in a specific position relative to the cylinder, the top unit being provided with thru holes corresponding to the one or more threaded holes. 7. Actuator for activating a valve according to any one of claim 3 and claim 5, wherein the outer end face of the cylinder is provided with one or more threaded holes for fixing the top unit in a specific position relative to the cylinder and the top unit is provided with one or more elongated holes, allowing the top unit to be rotated a certain angle. 8. Actuator for activating a valve according to claim 5, wherein the static seal is an O-ring arranged around the holes. 9. Actuator for activating a valve according to claim 1, wherein the top unit is a modular unit and further contains one or more of the following components: magnetic indicator of piston position, light indication of piston position, solenoid for activating the piston. 10. Actuator for activating a valve according to claim 1, wherein the actuator at least consists of a modular cylinder unit, a modular top unit and a modular yoke unit. 11. An actuator for activating opening and closing of a valve, and switchable between normally open and normally closed, the actuator comprising: a cylinder;a piston located in the cylinder;at least one top unit movably mounted on the cylinder to change a position of the top unit relative to the cylinder, the top unit including at least two connections for a pressurized fluid, the at least two connections including a first connection and a second connection;a spring comprising a closed space containing a pressurized fluid acting on the piston in the cylinder to hold the piston in a normally closed position or a normally open position;the top unit being movable relative to the cylinder to position the top unit in a first position relative to the cylinder in which the first connection in the top unit is connected to a first portion of the cylinder on one side of the piston through a first opening of the cylinder and the second connection is connected to a second portion of the cylinder on an opposite side of the piston through a second opening of the cylinder so that the actuator is normally open; andthe top unit being movable relative to the cylinder to position the top unit in a second position relative to the cylinder in which the second connection in the top unit is connected to a first portion of the cylinder through the first opening of the cylinder and the first connection is connected to the second portion of the cylinder through the second opening of the cylinder so that the actuator is normally closed. 12. The actuator for activating a valve according to claim 11, further comprising a static seal between the cylinder and the top unit. 13. The actuator for activating a valve according to claim 11, wherein an outer end face of the cylinder includes a plurality of symmetrically arranged threaded holes for fixing the top unit in a specific position relative to the cylinder, the top unit including thru holes positionally corresponding to the threaded holes in the outer end face of the cylinder. 14. The actuator for activating a valve according to claim 11, wherein an outer end face of the cylinder includes a plurality of threaded holes for fixing the top unit in a specific position relative to the cylinder, the top unit including thru holes positionally corresponding to the threaded holes in the outer end face of the cylinder. 15. The actuator for activating a valve according to claim 11, wherein the top unit contains at least one of: a magnetic indicator of piston position, a light indication of piston position and a solenoid for activating the piston. 16. The actuator for activating a valve according to claim 11, further comprising an O-ring seal between the cylinder and the top unit. 17. An actuator for activating opening or closing of a valve, where the actuator is of a type that is normally closed or normally open, the actuator comprising: a cylinder in which is positioned a piston, the piston being held in the normal position in the cylinder by a spring;the spring acting on the piston in the cylinder consists of a closed space with a pressurised fluid;at least one top unit with at least two connections for the pressurised fluid, one of the connections for pressurised fluid in the top unit being connected to a first portion of the closed space inside the cylinder through an opening of the cylinder and the other of the connections for pressurised fluid in the top unit being connected to a second portion of the closed space inside the cylinder through another opening of the cylinder, the first portion of the closed space inside the cylinder being positioned on one side of the piston and the second portion of the closed space inside the cylinder being positioned on an opposite side of the piston; andthe top unit being rotatably mounted on the cylinder and configured to rotate relative to the cylinder to change a position of the top unit relative to the cylinder and allow the connection between the connections and the first and second portions to be interchanged. 18. The actuator for activating a valve according to claim 17, further comprising a static seal between the cylinder and the top unit. 19. The actuator for activating a valve according to claim 17, wherein an outer end face of the cylinder includes a plurality of symmetrically arranged threaded holes for fixing the top unit in a specific position relative to the cylinder, the top unit including thru holes positionally corresponding to the threaded holes in the outer end face of the cylinder.