| 摘要 |
PROBLEM TO BE SOLVED: To reduce the number of parts used in a zoom camera and, at the same time, to reduce loss in the camera, by constituting a drive control mechanism for normally and reversely rotating a zoom motor which supplies two kinds of drive voltages to contain a total of four control transistors. SOLUTION: In a motor-driven zoom camera, two control transistors Tr10 and Tr4 are connected between a first power supply terminal 1 and a zoom motor 2. Therefore, the motor 2 can be rotated in the normal direction with a first constant voltage E1 by controlling control transistors Tr10 and Tr5 in turned-on states and control transistors Tr3 and Tr4 in turned-off states. On the contrary, when the transistors Tr10 and Tr5 are controlled to turned-off states and the transistors Tr3 and Tr4 are controlled to turned-on states, the motor 2 can be rotated reversely with the voltage E1. In addition, when the transistor Tr5 is controlled to a turned-on state and the transistors Tr10, Tr3, and Tr4 are controlled to turned-off states, the motor 2 can be rotated normally with a second constant voltage E2. |
