A daisy wheel type printing device comprises a daisy printing wheel including a plurality of type holding members having type at the respective ends thereof, wheel driving motor for rotating the daisy printing wheel to set the type designated by input character data to a printing position, a printing hammer for hitting the type set to the printing position, and a control circuit for driving the printing hammer when a preset a period of time has elapsed after the type designated by the input character data has arrived at the printing position. The preset period of time is varied in response to the rotation amount by which said daisy printing wheel is rotated to set the designated type at the printing position. The delay is larger for a wheel rotation of less than a predetermined amount than it is for a large rotation.
A three-phase sine wave signal synthesizing circuit comprises a pair of detectors for respectively generating substantially sinusoidal wave output signals having a phase difference of 120.degree. in terms of electric angle upon detecting a two-phase sine wave output generated by a signal generator and a pair of amplifiers for amplifying the output signals from the pair of detectors and transmitting the non-inverted output signals as a first-phase output signal and a second-phase output signal as well as an inverted signal. Terminals for transmitting the inverted signals from the pair of amplifiers are mutually short-circuited and a third-phase, non-inverted output signal is transmitted from the point of the short-circuit. Such circuit does not require a synthesizer to obtain a third-phase output signal and consequently can be significantly simplified to reduce its manufacturing cost. Moreover, such circuit can enhance the accuracy of three-phase sine wave output signals it transmits. A brushless motor drive circuit using a three-phase sine wave signal synthesizing circuit according to the invention can be significantly simplified to reduce its manufacturing cost.
There is a printer comprising: a type wheel having a plurality of types; a type selecting apparatus for making the type wheel operative and thereby to lead the type selected from those types to a printing position; a signal generator to generate a striking signal to a printing hammer for making this selected type toward a printing paper; and a signal generator to generate a carriage moving signal to move a carriage on which the type wheel, type selecting apparatus and printing hammer are mounted. In this printer, the time intervals from the time of generation of the hammer driving signal until the time of generation of the carriage moving signal and until the time of generation of a wheel rotating signal are respectively changed with respect to the area of the individual type of the plurality of types. The time interval from the time of generation of the striking signal until the time of generation of the carriage moving signal is set on the basis of the time interval of generation of the striking signal which is set with regard to the individual type area.
