PURPOSE: To perform detection of the rotation angle of a rotary shaft with high precision by a method wherein a position detecting means is formed with a disc in which detecting slits are formed, and photo interrupters formed such that an emission part is positioned facing a collecting part and detecting a detecting slit, and the disc is positioned close to the collecting part side.
CONSTITUTION: A flow rate control device transmits rotation from the drive source of a DC motor to a rotary shaft 42c for controlling a flow rate valve of a flow rate control part 42 through a flow rate control gear unit. The rotation angle of the rotary shaft 42c is detected by a position detecting means, and by means of a position detecting signal therefrom, feedback control is made on the DC motor. A disc 50 in which detecting slits 51a and 51b are formed is mounted on the rotary shaft 42c. The position detecting means is formed such that an emission part 52a and a collecting part 52b are positioned facing each other and photo interrupters 53a and 53b to detect the detecting slits 51a and 51b are provided. The disc 50 is arranged close to the collecting part 52b side of the photo interrupters 53a and 53b. Since the disc 50 is positioned close to the collecting part 52b side and no influence by interference and reflection of light is exercised, the rotation angle of the rotary shaft 42c can be detected with high precision.
| JP2004060912 | TEMPERATURE LEVELING DEVICE |
TANIGUCHI YOSHIKAZU
HIGUCHI MOTOHIRO
SHIMIZU TOMOYUKI
SUZUKI HITOSHI
