Auto power cut-off device for camera and driving method therefor

• US 5,309,195 A
• Filed: 12/31/1992
• Issued: 05/03/1994
• Est. Priority Date: 10/16/1992
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Aerospace Industries, Ltd. (Korea Aerospace Industries Limited)
• Inventors: Moon, Byeongjun, Goo, Bonjeong
• Primary Examiner(s): ADAMS JR, RUSSELL E
• Application Number:
  US07/999,614
• Time in Patent Office: 488 Days
• Field of Search: 354/484
• US Class Current: 396/302
• CPC Class Codes: G03B 7/26 Power supplies; Circuitry or arrangement to switch on the power source; Circuitry to check the power source voltage

Abstract

An auto power cut-off device for camera and a driving method which can automatically close an automatic lens cap and concurrently cut-off power supplied to an auxiliary circuit in case that a user does not use a camera during a predetermined time after supplying the power to the camera. The auto power cut-off device is constituted by a switch block including a power control for staring the operation of the automatic camera, an encoder switch which can be varied according to the state of the automatic camera, and an operation switch for controlling the operation of the camera. The power cut-off device also has a micro controller of outputting a signal to block the power supplied to the auxiliary circuits in case that the automatic camera is not used during a predetermined period after operation of the automatic camera beings; and a power control means for blocking the power supplied to the auxiliary circuits in case that the power cut-off signal is inputted from the micro controller.

Claims

1. A driving method for an auto power cut-off device for an automatic camera comprising the steps of:

initializing all the variables and auxiliary circuits of the camera after power voltage is applied to start operation;

reading whether a lens cap is closed in case to turning on of a power control switch;

reading whether the lens cap is closed by rotating a lens group driving motor in a reverse direction in case the lens cap was not closed;

cutting off the power supplied to auxiliary circuits after suspending the operation of the lens group driving motor in case that the lens cap is closed by rotating the lens group driving motor in the reverse direction;

reading whether the lens cap can be opened by rotating the lens group driving motor in a forward direction in case that the lens cap is closed after the power control means is turned ON;

reading whether an operation switch is turned ON after suspending the operation of the lens group driving motor in case that the lens cap is opened by rotating the lens group driving motor in the forward direction;

operation the camera in case that the operation switch is turn ON;

saving the present state of the camera after a predetermined time passes in case that the operation switch has not been turned ON;

suspending the operation of the lens group driving motor in case that the lens cap is closed after reading whether the lens cap is closed by rotating the lens group driving motor in the reverse direction;

cutting off the power supplied to the auxiliary circuits after the operation of the lens group driving motor is suspended; and

terminating all the operations.

2. Auto power cut-off device for an automatic camera comprising

a switch block including a power control switch for turning ON to start the operation of the automatic camera, an least one encoder switch indicating an ON/OFF state of the automatic camera, and an operation switch for controlling the operation of the camera;

a micro controller for outputting a cut-off signal to cut off the power supplied to auxiliary circuits of the camera in response to none-use of the automatic camera a predetermined period after the operation of the automatic camera begins; and

a power supplying control means for blocking the power supplied from a power voltage signal line to the auxiliary circuits in response to said power cut-off signal being inputted from said micro controller, said control means including

a first resistance with one terminal connected to a power supplying signal output terminal of said micro controller;

a transistor with a base connected to another terminal of said first resistance and with an emitter connected to ground;

a second resistance connected between a collector and said base of said transistor;

a third resistance with one terminal connected to said collector of said transistor;

a PNP type transistor with a base connected to another terminal of said third resistance and with an emitter connected to the power voltage signal line; and

a fourth resistance connected between an emitter and said base of said PNP type transistor.