JPH0377296U - - Google Patents

Description

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of one embodiment of the brushless motor drive circuit of the present invention, Fig. 2 is a waveform diagram illustrating the operation of generating three position detection signals from the outputs of two Hall elements, and Fig. 3 The figure is a servo block diagram explaining the operation of the servo that controls the rotational speed, FIG. 4 is a characteristic diagram of the servo circuit, FIGS. 5 and 6 are plan views explaining the mounting positions of the coil and Hall element, and FIG. The figure is a diagram explaining the configuration of the Hall element, Figure 8 is a waveform diagram explaining the operation when the attachment position of the Hall element is shifted, and Figures 9 to 11 are the states in which the coil and Hall element of the present invention are attached. 12 is a waveform diagram illustrating the operation when the Hall element and coil are installed in the proper position, FIG. 13 is a sectional view showing the configuration of an example of a conventional brushless motor, and FIG. 14 15 is a plan view showing the configuration of an example of a stator of a conventional brushless motor, FIGS. 15 and 16 are circuit diagrams illustrating the connection state of Hall elements, and FIG. 17 is a block diagram showing the configuration of a conventional speed control circuit. It is. 1...Stator, 2 to 4, 2an to 4b, 8
... Coil, 5 to 7... Hall element, 5a... Hall chip, 5d... Mold, 10... Brushless motor, 11... Rotating shaft, 12... Rotor, 13, 14...
Permanent magnet, 15... Bearing, 30... Flexible printed circuit board, 31... Holder, 32a to 34
b... Core, 51 to 53... Buffer amplifier, 54
...Addition circuit, 57...Matrix circuit, 58 to 60...Amplifier, 64...Speed comparison circuit, 66...Reference voltage comparison circuit.

Claims (1)

[Scope of claims for utility model registration] (1) First to third parts arranged at a predetermined distribution angle
a coil; first to third position sensing elements arranged at a predetermined flow angle; an adding circuit for adding the outputs of the first and second position sensing elements; a generating circuit that generates a signal with a phase corresponding to the flow angle position of the position sensing element No. 3; a drive circuit that drives the coil; a comparison circuit that compares the output of the third position sensing element with a predetermined reference value and outputs an error signal; and a drive circuit that drives the coil in response to the output of the comparison circuit. A brushless motor drive circuit comprising a control circuit for controlling the rotational speed of a rotor. (2) A holder in which the first to third coils are arranged at a predetermined circulation angle, and the first to third position detection elements are arranged at a predetermined circulation angle, and the rotation shaft of the rotor is inserted therethrough. a substrate in which a substantially circular hole is formed; a long hole formed on the substrate on a circle concentric with the hole in the substrate; and a long hole inserted into the long hole to fix the substrate to the holder. A brushless motor with screws.