Preferential power distribution system for battery powered camera having electronic flash unit

Claim 2

In combination with a camera having an electronic flash unit and a film transport motor, a source of electrical energy having an output voltage that fluctuates with use, means operable to supply energy from said source to said motor, and switching means responsive to the voltage of said source for supplying energy from said source to said flash unit when said voltage is above a predetermined value, whereby the energy of said source is available for supply to said motor without diminution by said flash unit when said voltage is below said predetermined value.

Claim 3

The apparatus of claim 1, in which said switching means comprises a relay, and means for connecting said relay to said source.

Claim 4

The apparatus of claim 1, in which said switching means comprises trigger circuit means for producing a first signal when said voltage is above said predetermined value and a second signal when said voltage goes below said predetermined value by a predetermined amount, and means responsive to said first signal for supplying energy from said source to said flash unit.

Claim 5

The apparatus of claim 2, in which said relay comprises contacts connected between said source and said flash unit and a winding responsive to a first voltage to close said contacts and responsive to a second voltage lower than said first voltage for opening said contacts, and means for connecting said source to said winding.

Claim 6

A photographic system comprising a camera having a lens and shutter, a strobe unit, a shutter button for operating the shutter, a film transport motor requiring a first voltage for operation, a battery, and means for connecting said battery to said motor, said strobe unit comprising a storage capacitor, a ready light connected to said capacitor for producing a light signal when said capacitor is charged to a predetermined voltage, charging circuit means connected across said capacitor, and responsive to applied voltage at least equal to a second voltage to charge said capacitor to said pedetermined voltage, voltage sensing means responsive to an applied voltage to produce a first signal when the applied voltage reaches or exceeds a third voltage higher than said second voltage and to produce a second signal when the applied voltage falls below said secoNd voltage, said second voltage being higher than said first voltage, manually operable switching means settable to first and second positions, means controlled by said manually operable switching means in its second position for connecting said battery to said voltage sensing means, and means controlled by said manually operable switching means and said voltage sensing means for supplying current from said battery to said charging circuit means when said manually operable switching means is in its second position and said first signal is present, whereby said light signal indicates that said strobe unit is in readiness for use and that said battery has sufficient residual capacity to operate said motor, and the absence of said light signal provides a low battery indication while said battery still has sufficient residual capacity to operate said motor.

Claim 7

A photographic system comprising a camera having a lens and shutter, a strobe unit, a shutter button for operating the shutter, a film transport motor requiring a first voltage for operation, a battery, and means for connecting said battery to said motor, said strobe unit comprising a storage capacitor, a ready light connected to said capacitor for producing a light signal when said capacitor is charged to a predetermined voltage, charging circuit means connected across said capacitor, and responsive to applied voltage at least equal to a second voltage to charge said capacitor to said pedetermined voltage, voltage sensing means responsive to an applied voltage to produce a first signal when the applied voltage reaches or exceeds a third voltage higher than said second voltage and to produce a second signal when the applied voltage falls below said secoNd voltage, said second voltage being higher than said first voltage, manually operable switching means settable to first and second positions, means controlled by said manually operable switching means in its second position for connecting said battery to said voltage sensing means, and means controlled by said manually operable switching means and said voltage sensing means for supplying current from said battery to said charging circuit means when said manually operable switching means is in its second position and said first signal is present, whereby said light signal indicates that said strobe unit is in readiness for use and that said battery has sufficient residual capacity to operate said motor, and the absence of said light signal provides a low battery indication while said battery still has sufficient residual capacity to operate said motor.

Claim 8

The apparatus of claim 5 in which said voltage sensing means comprises a relay having a winding and contacts closed when said third voltage is applied to said winding, said contacts being opened when a voltage not greater than said second voltage is applied to said winding, means connecting said winding in series with said battery when said manually operable switching means is in its second position, and means including a path over said contacts when closed for supplying current from said battery to said charging circuit.

Claim 9

The apparatus of claim 5, in which said voltage sensing means comprises a Schmitt trigger circuit responsive to the voltage of said battery when said manually operable switching means is in its second position, said trigger circuit being switched to produce said first signal when the voltage of said battery rises to at least said third voltage, and said trigger circuit being switched to produce said second signal when the voltage of said battery falls at least to said second voltage.

Claim 10

The apparatus of claim 7, in which said charging circuit means comprises a transistor having an emitter, a collector and a base, a voltage step up transformer having a primary winding connected in series with the emitter and the collector of said transistor and a tuned secondary winding, rectifying means coupling said secondary winding and said capacitor, and regenerative coupling means between said secondary winding and the base of said transistor, said regenerative coupling means being controlled by said trigger circuit and responsive to said first signal to cause oscillation in said secondary winding, said second signal being effective to quench oscillation in said secondary winding by biasing said transistor against conduction.

Claim 11

A preferential power distribution system for a camera having a plurality of power consuming devices including a strobe unit, said strobe unit being operable in response to an applied voltage above a first value and the other of said devices being operable in response to an applied voltage above a second value below said first value, said system comprising, at least a pair of supply terminals adapted for connection to a common electrical power supply subject to voltage variations in use, means for connecting said terminals to said other devices, and means responsive to voltage across said terminals for operatively connecting said terminals to said strobe unit when the voltage across said terminals rises to a third value higher than said first value and for effectively disconnecting said terminals from said strobe unit when the voltage across said terminals falls below said first value.

Claim 12

A preferential power distribution system for a camera having a plurality of power consuming devices including a strobe unit, said strobe unit being operable in response to an applied voltage above a first value and the other of said devices being operable in response to an applied voltage above a second value below said first value, said system comprising, at least a pair of supply terminals adapted for connection to a common electrical power supply subject to voltage variations in use, means for connecting said terminals to said other devices, and means responsive to voltage across said terminals for operatively connecting said terminals to said strobe unit when the voltage across said terminals rises to a third value higher than said first value and for effectively disconnecting said terminals from said strobe unit when the voltage across said terminals falls below said first value.

Claim 13

The apparatus of claim 9, in which said strobe unit comprises indicating means for producing a visible signal when said strobe unit is operable, whereby the absence of said visible signal indicates a voltage across said terminals below said first value while the voltage across said terminals is still sufficient to operate said other devices.

Claim 14

The apparatus of claim 9, in which said means responsive to the voltage across said terminals comprises a relay having a winding and contacts closed When the voltage across said winding rises to a value determined by said third value, said contacts being opened when the voltage across said windings falls below a value determined by said first value and lower than the voltage at which said contacts are closed, means for connecting said winding to said terminals, and means connecting said contacts in series between said terminals and said strobe unit.

Claim 15

The apparatus of claim 11, in which said strobe unit comprises indicating means for producing a visible signal when said strobe unit is operable, whereby the presence of said visible signal indicates a voltage across said terminals adequate to operate all of said power consuming devices, and the absence of said visual signal indicates a voltage across said terminals inadequate to operate all of said power consuming devices while the voltage is still adequate to operate said other power consuming devices.

Claim 16

The apparatus of claim 9, in which said means responsive to the voltage across said terminals comprises a voltage sensing trigger circuit switched to produce a first signal in response to an applied voltage equal to or greater than a value proportional to said third value and switched to produce a second signal in response to an applied voltage equal to or less than a value in the same proportion to said first value, and means responsive to said trigger circuit for operatively connecting or effectively disconnecting said terminals to said strobe unit according as said first or said second signal is produced, respectively.

Claim 17

The apparatus of claim 13, in which said strobe unit comprises indicating means for producing a visible signal when said strobe unit is operable, whereby the presence of said visible signal indicates a voltage across said terminals adequate to operate all of said power consuming devices, and the absence of said visual signal indicates a voltage across said terminals inadequate to operate all of said power consuming devices while the voltage is still adequate to operate said other power consuming devices.

Claim 18

A photographic system comprising a camera having a film transport motor, a battery, and an electronic flash unit, comprising means for supplying current to said motor from said battery, and means for sensing the voltage of said battery, means controlled by said sensing means for operatively connecting said battery to said flash unit when said battery voltage is above a first value and effectively disconnecting said battery from said flash unit when said battery voltage is below a second value lower than said first value.

Claim 19

A photographic system comprising a camera having a film transport motor, a battery, and an electronic flash unit, comprising means for supplying current to said motor from said battery, and means for sensing the voltage of said battery, means controlled by said sensing means for operatively connecting said battery to said flash unit when said battery voltage is above a first value and effectively disconnecting said battery from said flash unit when said battery voltage is below a second value lower than said first value.