PHOTOGRAPHIC APPARATUS WITH ELECTRICALLY OPERATED FOCAL PLANE SHUTTER

• US 3,696,727 A
• Filed: 12/19/1969
• Issued: 10/10/1972
• Est. Priority Date: 12/24/1968
• Status: Expired due to Term

• Current Assignee: Junichi Yokozato
• Original Assignee: Junichi Yokozato
• Inventors: Yokozato, Junichi
• Primary Examiner(s): Matthews, Samuel S.
• Assistant Examiner(s): Hayes, Monroe H.
• Application Number:
  US04/886,568
• Time in Patent Office: 1,026 Days
• Field of Search: 95/57,11.5R,53E,53EA,53EB,1CT
• US Class Current: 396/263
• CPC Class Codes: G03B 9/34 with adjustable slot; with mechanism controlling relative movement of blinds to form slot
• CPC Class Codes: G03B 9/70 with flash-synchronising contacts

Abstract

A focal plane shutter for photographic apparatus has front and rear shutter curtain release mechanisms, a shutter release device which is movable from a starting to an operative position to thereby actuate the front shutter curtain release mechanisms, a selector knob which is turnable between a first position to thereby set the shutter for bulb exposure operation and several additional positions to thereby set the shutter for operation with different preselected exposure times, an electric circuit including an electromagnet which is deenergized with a preselected delay following depression of the release device to thereby cause or permit actuation of the rear shutter curtain release mechanism and which remains deenergized in the first position of the selector knob because the electric circuit is then deenergized by a contactor which rotates with the selector knob, and an actuating device which actuates the rear shutter curtain release mechanism in response to movement of the release device back to its starting position while the selector knob dwells in the first position. The consumption of energy is reduced to zero when the selector knob dwells in such first position because the circuit of the electromagnet is then deenergized.

Claims

1. In a photographic apparatus, a combination comprising a focal plane shutter comprising front shutter curtain release means and rear shutter curtain release means;

a release device movable between a starting position and an operative position and arranged to actuate said front shutter curtain release means in response to movement to said operative position so that the shutter admits scene light;

selector means actuatable to set the shutter for bulb exposure operation and for operation with a preselected exposure time, including a changeover member movable between a first position and at least one second position;

an electric circuit including electromagnet means deenergized with a predetermined delay following the movement of said release means to said operative position in said second position of said changeover member, said electromagnet means comprising an armature movable from a first to a second position in response to deenergization of said electromagnet means to thereby actuate said rear shutter release means so that the shutter terminates the admission of scene light; and

actuating means for moving said armature to said second position in response to movement of said changeover member to said first position and for moving said armature to said second position in response to movement of said release device to said starting position in said first position of said changeover member so that said armature actuates said rear shutter release means without any change in the condition of said electromagnet means.

2. A combination as defined in claim 1, wherein said actuating means comprises a driving member movable along a predetermined path in response to movement of said release device to said starting position and a driven member which includes motion receiving first and second portions and a motion transmitting third portion, said first portion being located in the path of movement of said changeover member to move said second portion into the path of movement of said driving member in response to movement of said changeover member to said first position whereby said second portion is displaced by said driving member and moves said armature to said second position by way of said third position is response to movement of said release device to said starting position.

3. A combination as defined in claim 2, wherein said driven member is pivotable by said changeover member about a predetermined axis and is movable transversely of said axis by said driving member.

4. A combination as defined in claim 2, wherein said third portion of said driven member is a spring and said driving member is pivotable in response to movement of said release device.