US 5,381,064 A · Print wheel motor for encoder

Abstract

A plurality of stepper motors, each of which comprises a stator assembly and a rotor, are axially aligned to form with a control system an encoder for use in a printing apparatus. The rotors constitute print wheels which support different print characters. The stator assembly of each motor only extends above a part of the circumference of the associated rotor. This enables the axial extent of the print wheels to be reduced, A sensor arrangement is provided to enable the home position of each wheel to be determined. In operation, the control system receives desired print character information and rotates the associated rotor to the correct position for printing to take place. Once all rotors have been rotated to their desired position for printing, printing can then take place. The arrangement enables the printing process to run faster than previously.

Claims11

Dependent claims

Apparatus comprising a plurality of wheels arranged in a row, each wheel comprising a plurality of formations at equidistantly spaced positions around the wheel at a particular radius except for one position, known as a blank position, where the formation is missing, each wheel further including a home formation disposed adjacent the blank position but on a different radius, each wheel being movable relative to the others into one of a plurality of positions in which a processing member of each wheel is disposed at a processing point, one of said plurality of positions being designated a home position, each wheel being formed such that a sensor beam is transmitted through aligned formations in order to determine the home position of each wheel, said apparatus further comprising two position sensors which are disposed respectively on said particular radius and said different radius, respectively.

Dependencies are inferred from the claim text.

Print wheel motor for encoder

Life of this patent

Print wheel motor for encoder

Life of this patent

Abstract

Claims11