Document Type and Number:
Japanese Patent JPS5023937
Kind Code:
A
Abstract:
1417677 Printers INTERNATIONAL BUSINESS MACHINES CORP 1 May 1974 [27 June 1973] 19040/74 Heading G4H [Also in Division H2] A printer positioning system comprises a type carrier with character locations equally spaced about an axis of rotation, a stepper motor to rotate the type carrier, and a motor control circuit, the number of steps between character locations being equal to the number of phases of the motor. As disclosed, the motor has 4 phases and rotates 2 degrees per step, the character locations being spaced at 8 degrees, and the type carrier has 3 sets of 15 character locations each, for printing on cheques. N, S, E and W windings of the motor are energized in pairs in the sequence NE, SE, SW, NW by a Grey code counter 39 driven by an oscillator 36 while a "run" pulse 41 is present, the motor being initially detented in the NE position which corresponds to the centre line of a character location. However, after the second oscillator pulse, a damp pulse generator 37 drives the counter 39 back one step, from SW to SE, to damp out perturbations introduced on start up due to motor hunting. After the "run" pulse ceases, a stop pulse generator 38 produces two pulses to return the motor to the detent NE position.
Application Number:
JP6300274A
Publication Date:
March 14, 1975
Filing Date:
June 05, 1974
Export Citation:
International Classes:
B41J1/32; B41J7/34; B41J29/38; G06K15/14; (IPC1-7): G06K15/06