Patent ID: 6181098
Filing Date: 2001-01-30
Classification: G05B

Abstract:
A DC motor control circuit for controlling a DC motor, comprising:a rotational signal output circuit detecting a rotation of a DC motor, that is controlled by a control unit to attain a relative movement between a print head and a recording medium, and outputting a rotation signal indicative of the detected rotation;an operation signal output circuit receiving the rotation signal and outputting an operational signal, the operational signal including a movement direction signal indicative of a direction, in which the relative movement is attained between the print head and the recording medium, and a movement amount signal indicative of an amount of the relative movement between the print head and the recording medium;a position output circuit receiving the operational signal and outputting a positional value indicative of the relative position between the print head and the recording medium;a comparing circuit comparing the positional value with a first predetermined value, and outputting a matching signal when the positional value is matched with a first predetermined value;a switch circuit receiving the matching signal, and switching from outputting of a drive signal for driving the DC motor to outputting of a stop signal for stopping the DC motor;a controlled movement amount count circuit counting a movement amount value, controlled to be attained onto the relative movement, based on the movement amount signal;an actual movement amount count circuit counting an actual movement amount, by which the relative movement is actually performed, based on the movement amount signal, by incrementing the actual movement amount based on the movement amount signal when the movement direction signal indicates the same direction with a controlled direction signal that is issued from the control unit and that is indicative of the direction in which the control unit controls to attain the relative movement, and by decrementing the actual movement amount based on the movement amount signal when the movement direction signal indicates the opposite direction from the controlled direction signal;a reset circuit resetting the value counted by the controlled movement amount count circuit and the value counted by the actual movement amount count circuit when the value counted by the actual movement amount count circuit reaches a second predetermined value; anda stopped condition signal output circuit outputting, to the control unit, a signal indicating that the relative movement is stopped, when the value counted by the controlled movement amount count circuit reaches a third predetermined value that is greater than the second predetermined value.