Title:
【発明の名称】ズームレンズ駆動装置
Document Type and Number:
Japanese Patent JP2919700
Kind Code:
B2
Abstract:
PURPOSE:To provide a zoom lens driving device low in noise by setting the voltage of the low voltage side of a PMW driving voltage generated from a PMW generation circuit to a voltage value higher than the minimum starting voltage for driving a DC motor. CONSTITUTION:A high or low signal outputted from output terminals ZSW1, ZSW2 is supplied to a switching circuit 12 by operating zoom switches SW1, SW2 for the forward/backward rotation of a motor 13. The voltage of the low voltage side of the PMW driving voltage outputted from a transistor Q1 is set at the voltage value V2 higher than the minimum starting voltage V0 for driving the DC motor 13. When the motor 13 is driven by such PMW driving voltage, the motor is rotated at high speed in a period A (high level period), and the motor 13 is rotaed and driven at low speed without being stopped in the period B (low level period). Thus, the vibration peculiar to the PMW drive is suppressed, and the occurrence of a noise is reduced.
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Inventors:
SUGIMOTO KAZUHIKO
Application Number:
JP9434493A
Publication Date:
July 12, 1999
Filing Date:
April 21, 1993
Export Citation:
Assignee:
SANYO DENKI KK
International Classes:
G02B7/04; G02B7/08; H02P7/29; H04N5/232; (IPC1-7): G02B7/04; G02B7/08; H02P7/29; H04N5/232
Domestic Patent References:
| JP3155385A | ||||
| JP4290A |
Attorney, Agent or Firm:
Koji Yasutomi (1 person outside)