| 摘要 |
PURPOSE:To move a photographic lens to its reset position prior to other operations by providing a holding circuit which keeps a motor driving circuit ready to drive a motor in another direction when a lens position detecting means and a half-depression detecting means are in the 2nd state respectively. CONSTITUTION:When a half-depression switch 1 is turned off during the operation of a shutter control circuit 15, the output of a NAND gate 11 falls to L and RS latch circuits 12 and 13 hold their output at H; and the outputs of an inverter 16 and an AND gate 14 goes up to H simultaneously with the completion of the operation of the shutter control circuit 15 to feed electricity to the motor reversely, and the photographic lens begins to be driven to its reset position. When the half-depression switch 1 is turned off after the completion of the operation of the shutter control circuit 15, the output of the NAND gate 11 falls to L and the RS shutter circuits 12 and 13 hold their outputs at H; and the output of an AND gate 14 rise to H and the photographic lens beings to be driven to the reset position. Consequently, when the motor is made to ready to operate, the movement of the photographic lens to the reset position is restarted prior to other operations.
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