초록 ▼

When the battery voltage is sufficient, and not nearing the point of insufficiency, a light-emitting diode is steadily illuminated. As the battery voltage decreases, the steady component of illumination decreases and also, when the decrease has proceeded to a certain extent, a superimposed pulsating

When the battery voltage is sufficient, and not nearing the point of insufficiency, a light-emitting diode is steadily illuminated. As the battery voltage decreases, the steady component of illumination decreases and also, when the decrease has proceeded to a certain extent, a superimposed pulsating component of illumination is introduced, causing the illuminated LED to begin to flicker, informing the user that the battery voltage is nearing insufficient values. As battery voltage drops further, the steady component of illumination ceases altogether, and the flicker converts to on-off blinking, indicating that the battery voltage is at the verge of an insufficient value. When the battery voltage drops further, the LED ceases to be illuminated. During part or all of the flicker phase, and/or during part or all of the blinking phase, the frequency of the pulsating component of illumination progressively increases with decreasing battery voltage, to create an effect of increasing urgency. In addition, or alternatively, at a certain point during pulsating illumination the frequency of the pulsating component is abruptly increased, likewise to create an effect of urgency.

대표청구항 ▼

In a still or motion-picture photographic camera having a battery, a battery-monitoring circuit operative for monitoring the condition of the battery and indicating battery condition to the user, the circuit comprising an indicator element; a controllable-conductivity semiconductor element connected

In a still or motion-picture photographic camera having a battery, a battery-monitoring circuit operative for monitoring the condition of the battery and indicating battery condition to the user, the circuit comprising an indicator element; a controllable-conductivity semiconductor element connected to the battery and to the indicator element and operative when conductive for carrying energizing current for the indicator element to cause the indicator element to generate a indication having a first character; an astable multivibrator also connected to the battery and to the indicator element and operative when switched on for causing the indicator element to be energized to generate an indication having a different second character; and means connected to the battery, the semiconductor element and the astable multivibrator operative for maintaining the semiconductor element conductive when the battery voltage is in a first range and operative for preventing and permitting oscillation of the astable multivibrator when the battery voltage is outside or in a second range, respectively, the astable multivibrator comprising an operational amplifier having inverting and non-inverting inputs, and RC-stage connected to the inverting input and a reference voltage divider connected to the battery and having a tap connected to the non-inverting input, said means including a semiconductor switch having a main-electrode path connected to the astable multivibrator to prevent and permit oscillation of the multivibrator in dependence upon the conduction state of the semiconductor switch and a voltage divider connected to the camera battery and having a tap connected to the control electrode of the semiconductor switch. In a still or motion-picture photographic camera having a battery, a battery-monitoring circuit operative for monitoring the condition of the battery and indicating battery condition to the user, the circuit comprising an indicator element, and means operative when the battery voltage is in a high range for effecting simple steady illumination of the indicator element, when the battery voltage is in a lower range effecting a pulsating illumination of the indicator element with a frequency which progressively increases as the battery voltage progressively declines, and ceasing to illuminate the indicator element at all when the battery voltage has declined to a predetermined value.