Document Type and Number:
Japanese Patent JPS4851632
Kind Code:
A
Abstract:
Both the position and its time derivatives, such as velocity, of a continuously moving information bearing medium, such as perforated motion picture film, with respect to a predetermined position of apparatus for handling the information bearing medium are derived by a transducer with a specially shaped sensor element adapted to sense indicia, such as sprocket holes of motion picture film, carried by the information bearing medium. The sensor element includes at least first and second members located a predetermined distance apart, and the transducer is fixedly located with respect to the indicia carried by the moving information bearing medium so that the indicia successively engage the first and second members of the sensor element. The transducer derives a first signal indicative of the position of the moving information bearing medium when the indicia engages the first member. The transducer derives a second signal when the indicia engages the second member, and the velocity of the moving information bearing medium is derived from the predetermined distance and the time period between the first and second signals. The sensor may be provided with further members from which may be derived the instantaneous acceleration of the moving information bearing medium and further derivatives of the position, velocity and acceleration of the moving information bearing medium. The transducer may comprise a single piezoelectric element which is deflected by the engagement of the sprocket holes of the movie film by the first and second members of the sensor.
Application Number:
JP10536172A
Publication Date:
July 20, 1973
Filing Date:
October 23, 1972
Export Citation:
International Classes:
G03B1/18; G01P3/66; G03B21/11; G03B21/43; G03B31/02; G03B35/24; G06K17/00; (IPC1-7): G06K7/04