Abstract: There is provided an apparatus for measuring a position of a linear type valve which is open/shut by operation of a hydraulic cylinder. More particularly, the apparatus more accurately measures a valve position by outputting a rotation angle of a rotation sleeve which rotates by being operatively connected to a hydraulic cylinder which moves linearly, and by calculating a vertical movement distance of a valve gate which changes in proportion to the rotation angle. Further, since the structure of the apparatus is very simple, the cost of production is significantly reduced. In addition, for use, the apparatus is installed on the hydraulic cylinder by a simple method.

Abstract: There is provided a multi-turn hydraulic actuator used to open/close a passageway in ground and sea industries including general industrial machines, oil refineries and chemical plants and power generating plants, among others, and more particularly, a multi-turn hydraulic actuator comprising: a hydraulic motor and a decelerator, among others, whereby high torque is efficiently obtained by using low electric power, compared to a conventional electric actuator, and whereby an operation part and a drive part are freely attached to/detached from at a user's necessity.

Abstract: A clutch apparatus for an electric valve actuator, in which, where a manual handle is operated by an operator in a state that a power supply is stopped in a main motor, a coupling state between the manual handle and the main motor is released and the main motor is separately driven during a re-supply of the power, whereby preventing a safety accident of the operator of the manual handle.

Abstract: Disclosed is a device for sensing the opening degree of a valve, which can easily determine the upper and lower limits without using upper and lower limit switches so that, besides simplifying the mechanical structure, the device can be easily installed, maintained, and repaired. The device can avoid basic errors and improve the opening degree sensing performance without using upper and lower limit switches, cams, and a spline so that, by simplifying the mechanical structure, the device can be manufactured, installed, maintained, and repaired at a low cost, and its long-term durability is improved. The device has a main gear adapted to disengage from the meter gear when the main gear is rotated excessively so that any damage to the meter gear and potentiometer, which may occur during installation or use, is prevented.

Abstract: The present invention relates to an apparatus operating a hydraulic actuator for valve, which can manually operate the hydraulic actuator for opening and closing the valve by which a flow rate is adjusted. According to the present invention, by manually operating the hydraulic actuator for opening and closing the valve, there is an advantage of manually opening and closing the valve and thus easily adjusting a flow rate of fluid flowing in a pipe, even when power is cut off. Further, according to the present invention, the hydraulic actuator for opening and closing the valve can be selectively connected with a hydraulic power pack so as to automatically open and close the valve using the hydraulic power pack according to a user's selection, or which can manually open and close the valve.

Abstract: Disclosed is a device for sensing the opening degree of a valve, which can easily determine the upper and lower limits without using upper and lower limit switches so that, besides simplifying the mechanical structure, the device can be easily installed, maintained, and repaired. The device can avoid basic errors and improve the opening degree sensing performance without using upper and lower limit switches, cams, and a spline so that, by simplifying the mechanical structure, the device can be manufactured, installed, maintained, and repaired at a low cost, and its long-term durability is improved. The device has a main gear adapted to disengage from the meter gear when the main gear is rotated excessively so that any damage to the meter gear and potentiometer, which may occur during installation or use, is prevented.

Abstract: The present invention relates to an apparatus operating a hydraulic actuator for valve, which can manually operate the hydraulic actuator for opening and closing the valve by which a flow rate is adjusted. According to the present invention, by manually operating the hydraulic actuator for opening and closing the valve, there is an advantage of manually opening and closing the valve and thus easily adjusting a flow rate of fluid flowing in a pipe, even when power is cut off. Further, according to the present invention, the hydraulic actuator for opening and closing the valve can be selectively connected with a hydraulic power pack so as to automatically open and close the valve using the hydraulic power pack according to a user's selection, or which can manually open and close the valve.