Automatic, remote operator for manually operable valve

Claim 1

For a valve having a shaft rotatable through more than 360 degrees for fully opening the valve when it is fully closed and for fully closing the valve when it is fully open, an automated, remote opening and closing unit, comprising: an electric motor having a rotary output shaft and being provided with a power supply means for providing electrical power for operating the motor to rotate the output shaft of the motor; rotary power transmission means connecting the rotary output shaft with the rotatable shaft of the valve, so that rotation of the power transmission means in one sense normally opens the valve and rotation of the power transmission means in the opposite sense normally closes the valve; a degree of openness transmitting means linked to the rotatable shaft of the valve, for normally providing a signal which is interpretable to provide an indication of the extent to which the valve that is being controlled is in an open condition; a control panel disposed remotely from the valve to be controlled thereby; the control panel including: degree of openness receiver for receiving said signal and for providing as an interpretation thereof an indication of the extent to which the valve that is being controlled is in an open condition; and a power supply controlling switch means linked to the power supply for said motor and operable to provide the supply of power to the motor for rotating the power transmission means in both said one sense and said opposite sense to change the degree of openness of the valve, and for interrupting the supply of power to the motor for maintaining the valve at a selected degree of openness; the rotary power transmission means including: a speed reducer; first endless belt means driving the speed reducer from the rotary output shaft of the motor; limit switch means interposed in the power supply means and sensitive to the attainment by the valve of a fully open and a fully closed condition and for then interrupting application of rotary power to the rotatable shaft of the valve, in order to prevent over-torquing of the rotatable shaft once an extreme of rotation is reached; second endless belt means between the speed reducer and the limit switch means and third endless belt means between the degree of openness transmitter, respectively, for coordinately driving the limit switch means and the degree of openness transmitter from the speed reducer.