JPH1144901A - Camera and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a camera and an electronic equipment which can enhance the reliability of battery check. SOLUTION: This camera has plural loads 8, 9, and 10 supplying power from a battery, plural modes performing specified energizing on the respective loads, a battery voltage detecting means 4, a reference voltage setting means 1 capable of setting a first reference voltage value and a reference voltage value which is lower than the first one, a comparing means 1 comparing the detected battery voltage with the reference voltage, a storing means 12 storing information related to the operating mode of the camera performed just before, a time measuring means 7 measuring the elapsed time after the operating mode of the camera is performed, and a means 1 for setting the measuring time of the means 7; and the inhibition of operation or warning are performed in accordance with the output of the comparing means. In this case, the output of the reference voltage setting means can be switched only in the time set by a time setting means in accordance with the stored contents of the means 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a camera and an electronic apparatus, and more particularly, to the reliability of a camera battery check.

[0002]

2. Description of the Related Art In recent years, the development of electronic devices has been remarkable, and the size and weight of electronic devices in which portability has been particularly emphasized have been increasing. In order to reduce the size and weight of the batteries used to operate these electronic devices, there have been some batteries in which the battery voltage is reduced or the internal resistance is sacrificed to some extent.

[0003] With the advance of miniaturization of cameras, such batteries are being actively employed. When such batteries are used, when the batteries are exhausted or batteries with large internal resistance are used. In this case, or immediately after the application of a large current load, a considerable time is required for the power supply voltage to recover. For example, when a strobe is charged, a considerable load is supplied from the battery, so that the battery voltage temporarily drops. Thereafter, the battery voltage recovers over a period of several tens of seconds to several minutes.

Therefore, in a camera using such a battery, once charging of the strobe is performed, a phenomenon occurs in which the battery voltage temporarily drops for several minutes thereafter, and the camera is used at that time. If the battery is already depleted to some extent, it will reach the battery check voltage that guarantees normal operation of the camera at that point. After a while, if the battery recovers, a state where the battery can be used normally is generated although the battery cannot be used normally, and the operability is significantly reduced.

[0005] In a camera having a display means, a battery warning display is further displayed, which confuses the user.

In order to avoid such a phenomenon, for example,
Japanese Utility Model Application Publication No. Sho 56-1567317 discloses a method of selecting a reference voltage to be compared with a power supply voltage from a plurality of reference voltages for each of a plurality of shooting modes.

[0007]

However, in the above-mentioned conventional example, Japanese Utility Model Application Laid-Open No. 56-167317 describes that a reference voltage to be compared with a power supply voltage for each of a plurality of photographing modes is selected from a plurality of reference voltages. Is to do
When a specific photographing mode is selected, there is a problem that it is easy to imagine that the same disadvantages as those in the related art occur in the same manner.

[0008] Japanese Utility Model Application Laid-Open No. 2-47631 discloses, as a related prior art, a method in which when a battery check is performed at the time of charging a strobe, a display is provided so that the batteries are sufficient regardless of the battery voltage. However, in this case, even when the battery voltage is really low and normal operation cannot be expected, a display indicating that the battery is sufficient is given, thereby causing a problem of giving a misunderstanding to the user. is there.

Japanese Patent Application Laid-Open No. Hei 4-50935 discloses a related art as a prior art in which a drive mode in which the actuator has a large load and a drive mode in which the actuator has a small load can be selected. Is selected, a variable control method is proposed in which a higher value is set as the comparison reference voltage than when the drive mode with a smaller load is selected, but this also depends on the actual battery type and state. There is a problem that it is hard to say that the variable control follows the variable control with high reliability.

Therefore, an object of the present invention is as follows.
In order to solve the conventional problems, it is an object of the present invention to provide a battery check type camera having improved operability in consideration of battery characteristics while enhancing the reliability of battery check and warning display.

A second object of the present invention is to provide a battery check system having excellent operability in consideration of the characteristics of the battery while improving the reliability of the battery check and the warning display after the flash charging operation. It is to provide a camera.

A third object of the present invention is to improve the reliability of battery check and warning display without being affected by temperature and to provide a battery check system having excellent operability in consideration of battery characteristics. To provide a camera.

A fourth object of the present invention is to improve the reliability of battery check and warning display regardless of the degree of battery consumption and to provide a battery check system having excellent operability in consideration of battery characteristics. To provide a camera.

Further, the object of the invention described in claim 5 is to improve the reliability of battery check and warning display regardless of the type of battery used in the camera and to have excellent operability in consideration of the characteristics of the battery. It is an object of the present invention to provide a battery check type camera.

Still another object of the present invention is to provide a camera capable of accurately detecting whether or not a large load has been supplied in advance for switching the reference voltage.

It is a further object of the present invention to provide a camera which accurately detects the type of battery used and switches the reference voltage, thereby improving the reliability of the battery check.

[0017]

According to a first aspect of the present invention, there is provided a configuration for realizing the object of the present invention, wherein a plurality of loads supplied with electric power from a battery and a predetermined load is supplied to each load. A plurality of modes for energizing the battery, battery voltage detecting means for detecting a voltage of the battery, reference voltage setting means for setting a first reference voltage value and a lower reference voltage value, and Comparing means for comparing the battery voltage with the output of the reference voltage setting means; storage means for storing information relating to the operation mode of the camera executed immediately before; and clocking for measuring an elapsed time since execution of the operation mode of the camera immediately before Means, and a time setting means for setting a time to be measured by the time measuring means. In a camera for prohibiting operation or warning in accordance with an output of the comparing means, There the output of the reference voltage setting means in the camera, characterized in that switch only time set by the time setting means.

According to this configuration, the output of the reference voltage setting means is switched only for the time set by the time setting means in accordance with the contents stored in the storage means, so that the battery check accurately corresponds to the state of the battery. Warning display can be performed.

In a specific configuration for realizing the object of the invention according to the present application, one of the plurality of operation modes is a strobe charging operation as described in claim 2. In the camera.

According to this configuration, a battery check corresponding to the state of the battery immediately after charging the strobe and an accurate warning display can be performed.

In another specific configuration for realizing the object of the invention according to the present invention, the output of the reference voltage setting means or the output of the time setting means is variable according to the temperature. 3. The camera according to claim 1, wherein:

According to this configuration, it is possible to perform a battery check corresponding to the state of the battery due to a change in temperature and display an accurate warning.

According to another specific configuration for realizing the object of the invention according to the present invention, the output of the reference voltage setting means or the output of the time setting means is provided by the battery voltage detecting means. 3. The camera according to claim 1, wherein said camera is variable according to an output.

According to this configuration, accurate battery check and warning display corresponding to the output of the battery voltage detecting means can be performed.

According to another specific structure for realizing the object of the invention according to the present invention, the output of the reference voltage setting means or the output of the time setting means depends on the type of battery. 3. The camera according to claim 1, wherein the camera is variable.

According to this configuration, the type of the battery is detected, and a battery check corresponding to the type of the battery and an accurate warning display can be performed.

According to another specific configuration for realizing the object of the invention according to the present application, the information on the operation mode of the camera immediately before being stored in the storage means is as follows.
The camera according to any one of claims 1 to 4, wherein the camera has a strobe charged bit indicating strobe charging, a film rewinding bit by a predetermined amount indicating film rewinding, and an elapsed bit indicating time elapse.

According to this configuration, a large load supply operation for strobe charging or rewinding of a predetermined amount of film is performed;
It is possible to reliably detect the elapsed time after the execution, and to perform a battery check corresponding to the state of the battery immediately after supplying a large load and an accurate warning display.

According to another configuration for realizing the object of the invention according to the present application, the type of the battery is detected by a battery type detecting means as an internal battery or an external battery. The camera according to claim 5, wherein:

According to this configuration, it is possible to accurately detect whether the battery is a small battery loaded in the camera or a large battery mounted outside, and perform a corresponding battery check and an accurate warning display.

According to another aspect of the present invention, in an electronic apparatus having a load to which power is supplied from a battery, a voltage for detecting a voltage of the battery is provided. Detecting means; determining means for comparing the detected voltage with a first reference voltage to determine a battery state; and a second reference which is lower than the first reference voltage within a predetermined time after driving the load. An electronic device is set to a voltage.

According to this configuration, a battery check according to the state of the battery and an accurate warning display can be performed.

According to another configuration for realizing the object of the invention according to the present application, the reference voltage is set to a voltage higher than the second reference voltage after a predetermined time elapses. The electronic device according to claim 8, wherein

According to this configuration, accurate battery check and warning display can be performed.

Another structure for realizing the object of the invention according to the present application is that, when the drive amount of the load is smaller than a predetermined amount according to the drive amount of the load, the reference 10. The electronic device according to claim 8, wherein setting the voltage to the second reference voltage is prohibited.

According to this configuration, the reference voltage can be set to one.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1 to 5 are views according to a first embodiment of the present invention. FIG. 1 shows the first embodiment of the present invention.
It is a block diagram of a camera concerning an embodiment. FIG. 2 is a diagram showing a change in battery voltage of the camera shown in FIG. FIG. 3 is a flowchart of the operation of the camera shown in FIG. 1 at the time of flash charging. FIG. 4 is a flowchart of the operation when the operation switch of the camera shown in FIG. 1 is pressed. FIG.
4 is a flowchart of an operation when an interruption of a clock timer of the camera shown in FIG. 1 occurs.

In FIG. 1, reference numeral 1 denotes a CPU for controlling the sequence of the entire camera, and 2 denotes an A / D built in the CPU 1.
Converter 3, temperature detecting means for outputting an analog signal proportional to temperature, 4 battery voltage detecting means for outputting an analog signal corresponding to the battery voltage of the camera, 5 information display means for displaying the state of the camera, 6 Is a high-speed oscillator for operating the CPU 1, 7 is a low-speed oscillator for controlling the time and clock functions of the CPU 1, 8 is a flash circuit of the camera and inputs a divided output of the charging voltage of the main capacitor to the A / D converter 2. doing. 9 is a film feeding motor, 10 is a film feeding means for winding and rewinding the film by the motor 9, 11 is an exposure control means for exposure, 12 is an EEPROM for storing adjustment data for each camera, and 13 is an EEPROM. The switch detection means 14 for detecting the operation switch and the state detection switch is a DC / DC converter for boosting the battery voltage.

First, the DC / DC converter 14 is activated to enable the high-speed operation of the CPU 1 and the operation of the A / D converter 2. Thereafter, the output of the temperature detecting means 3 is A / D converted by an A / D converter 2 built in the CPU 1 to obtain temperature information. Next, the output of the battery voltage detecting means 4 is A / D converted to obtain battery voltage information. Generally, in order to obtain more accurate information on the battery at this time, a predetermined current is applied to a load in the camera (for example, energization in a shutter closing direction (not shown)), and the battery voltage is changed to A during this energization. By performing the / D conversion, information on the battery voltage including the effect of the output impedance of the battery is obtained.

In general, when this voltage drops to a voltage at which the operation of the camera cannot be guaranteed or an operation prohibition voltage, the operation of the camera is prohibited to prevent a malfunction or a possible failure. The CPU 1 controls.

In a camera having a display means, when the battery voltage decreases to an operation warning voltage higher than the operation prohibition voltage of the camera, the display means informs the user of the replacement of the battery. Some cameras have a warning display.

The input range of the A / D converter 2 is 0 to 2.5 V.
And the resolution is 8 bits. If the battery is a 3V battery, the output of the battery voltage detecting means 4 divides the battery voltage by one-to-one resistance,
The half value of the battery voltage is output to the A / D converter 2. That is, for example, if the battery voltage at the time of battery check is 2.5 V, the output of the battery voltage detecting means 4 is 1.25 V, and as a result of A / D conversion,
CPU 1 obtains 80H.

Here, assuming that the first reference voltage value, that is, the voltage for judging whether or not to prohibit the operation when the battery check is executed under the current battery voltage in a steady state is 70H, the battery check When the battery voltage is (2.5
V / 256) × 70H × 2 = 2.19V or less,
The CPU 1 determines that the subsequent normal operation of the camera is impossible, displays an operation prohibition state on the information display means 5, does not perform the subsequent operation (such as shutter drive), and waits for the operation switch to be pressed again. Enter the wait state.

This is an operation prohibition state, and a battery check is performed when the operation switch is pressed again. If the operation prohibition voltage is exceeded, operation is possible. If the operation prohibition voltage is not exceeded, no camera operation is performed. Not performed.

Next, the release switch is operated, and as a result of the battery check, it is determined that the battery voltage is sufficient to execute the operation of the camera, and the sequence of the camera proceeds.
When the strobe is charged, a large amount of energy is supplied from the battery to the capacitor in the strobe circuit 8, so that the battery voltage drops considerably during charging. Therefore, the charging operation is temporarily stopped, and if there is no other large load, the once lowered battery voltage gradually recovers. This is shown in FIG.

In a conventional battery having a large external shape, the voltage drop during charging is relatively small because the internal resistance of the battery is small, and the recovery time of the battery voltage after the completion of charging is short. On the other hand, in recent miniaturized batteries, since the internal resistance is large, the voltage drop during charging is large, and the recovery time after completion of charging is longer.

Further, when the battery is kept at a low temperature, both the internal resistance and the recovery time increase. That is, after the charging operation is stopped, if the battery is checked again until time T1, the operation of the conventional battery is prohibited because the battery voltage is lower than the first reference voltage. Similarly, if the battery is miniaturized, the operation is prohibited until the time T2 after stopping the charging operation, and if the temperature is still lower, until the time T3 after stopping the charging, if the battery check is performed during this time. I understand.

Certainly, at this point, the battery voltage has actually dropped, but this is because the battery voltage has temporarily dropped due to the supply of a large load. It is not a drop. Therefore, in order to improve the operability without impairing the reliability of the battery check when operating the camera using such a battery that is known to recover after a while, in this embodiment, the camera Focusing on the charging operation of the strobe with the largest load among the operations of the above, when the charging operation of the strobe is executed, the information is stored and the reference voltage of the battery check is set to the first voltage until a certain time elapses after the execution. The reference voltage is changed to a reference voltage lower than one reference voltage. That is, if the battery check operation is performed again within a certain period of time after the completion of flash charging, a follow-up control that permits the operation of the camera up to a battery voltage lower than the normal operation prohibition voltage is dealt with.

Next, the operation will be described mainly with reference to the flowcharts shown in FIGS. Note that “S” in the following flowcharts represents a step.

First, A / D conversion is performed on the current charging voltage of the main capacitor (S101). If the strobe has not fired since the previous charge, there should be sufficient charge stored in the main capacitor, and the strobe can emit light with a small supplementary charge. Since charging is completed with much less energy than when charging is started from the state described above, since such a case does not correspond to the heavy load considered in the present embodiment, such a case is detected. For this purpose, a charging voltage detection procedure is performed.

When the charging result is less than the predetermined amount, a large amount of energy is supplied from the battery in the subsequent charging operation, and nothing is performed when the charging result is more than the predetermined amount.

Next, the result of the A / D value is determined (S10).
2). Here, the result of the A / D conversion is converted to the main capacitor voltage of the strobe, and it is determined whether the result is greater than, for example, 50V.

When the voltage is 50 V or less, a large load is supplied in the subsequent charging process.
A predetermined bit at a predetermined address of the PROM 12 (this bit is called a strobe charged bit) is set to 1 (S1).
03).

A charge start command is output to the flash circuit 8 (S104). When the charging voltage of the main capacitor reaches a predetermined voltage set in the flash circuit, the flash circuit stops charging and outputs to the CPU 1 that the charging voltage has reached the predetermined voltage. After outputting the charge start command, the CPU 1 waits for a charge completion signal (S105). At this point, it is actually necessary to prepare for a case where the charge completion signal is not output within a predetermined time for safety measures, but is omitted here for simplification.

When the charging completion signal is detected, the charging sequence of the strobe is terminated. Thereafter, control of the focus lens, control of the shutter, and the like are performed as necessary, and a sequence such as light emission of the strobe is performed. Is completed.

Next, after the photographing is completed or the next switch operation is completed upon completion of the charging of the strobe, the state shown in FIG.
This will be described with reference to the flowchart of FIG.

Wait for the operation switch to change. At this time, the CPU 1 is set to accept an interrupt of the clock counter clocked by the low-speed clock (S11).
0). In this state, a change occurs in the operation switch, and the CPU 1
Performs a predetermined operation according to the operated switch. In that case, first, a battery check is performed.

The battery voltage is measured by A / D conversion by the battery voltage detecting means 4 in a state where a predetermined load is supplied (S111). Next, the result of the A / D conversion is compared with a reference voltage to determine whether or not to prohibit the operation.
The information of the flash-charged bit of the EEPROM 12 is read (S112).

The result read from the EEPROM 12 is
It is determined whether it is set to 1 (S113).
If the battery voltage remains at 0, it is determined that the battery voltage is in a sufficiently steady state because a large load such as charging of the strobe has not been supplied immediately before. The reference voltage 70H is used (S11
4).

If it has been set to 1, it is determined that the flash has been charged immediately before and that the battery voltage has temporarily dropped, and the first reference value is used as the battery voltage comparison reference value. Set 60H obtained by subtracting 10H from 70H (S
115).

The reference voltage set in steps S114 and S115 is compared with the battery voltage previously A / D converted (S116). When 70H is set as the reference voltage, the operation prohibition voltage is 2.19 V as previously obtained, but when 60H is set as the reference voltage,
(2.5V / 256) × 60H × 2 = 1.88V, and the operation inhibition voltage is 1.88V.

If the battery voltage is higher than any of the previously set reference voltages, it is determined that the camera is operable, and the sequence of the camera according to the operation switch is executed (S117).

If it is determined that the battery voltage does not reach any of the reference voltages, it is determined that the camera is not functioning properly, and the information display means 5 is displayed to indicate that the camera is in a forbidden state.
It returns to 110 (S118).

Next, the processing when an interrupt is generated by the clock counter will be described with reference to the flowchart of FIG.

Now, the camera measures the time by the low-speed oscillator 7 and displays the clock information on the information display means 5. For this reason, when an interrupt of the clock counter occurs, the clock data stored in the RAM (not shown) and the elapsed time of the clock timer are added and written again in the RAM (S12).
0).

Next, as a result of updating the clock data, it is determined whether or not the display means needs to be rewritten (S12).
1). Generally, the clock information displays the date, time, date and time, and so on. In such a case, if the “minute” of the clock is increased, the clock display on the display means is updated. There is a need.

If the display needs to be updated, the display is updated (S122). Since an interrupt of the clock counter generally occurs in a time shorter than one minute, it is necessary to rewrite the display once every several tens of timer interrupts. Further, in the present embodiment, when it is necessary to update the display, that is, it is determined whether or not 1 is set to the strobe charged bit of the EEPROM 12 every minute.

That is, the flash-charged bit of the EEPROM 12 is read (S123), and the flash-charged bi is read.
It is determined whether or not t is set to 1 (S12)
4). If the flash-charged bit is not set to 1, there is no history of charging the flash immediately before, so the interrupt processing ends without doing anything.

On the other hand, when the flash-charged bit is set to 1, the elapsed bit which records the elapsed time from the detection of the flash-charged bit in a specific bit at a predetermined address of the EEPROM 12 is read ( S12
5). That is, if the elapsed bit is 0, the strobe charged bit becomes 1 after the previous clock timer interrupt.
, That is, within 1 minute after charging the flash, and if this elapsed bit is 1, it can be determined that the charging is within 1 minute or more and within 2 minutes after charging the flash.

Then, it is determined whether or not the elapsed bit is 1 (S126). If the elapsed bit is 1, since at least one minute has elapsed since the strobe was charged,
Battery voltage is judged to have recovered, strobe charged bi
While resetting t to 0, the elapsed bit is also reset to 0 (S127).

If the elapsed bit is 0, it is determined that the battery voltage has not recovered since one minute has not yet elapsed, and the elapsed bi is waited for another one minute to elapse.
t is set to 1 and the interrupt processing is terminated (S12).
8).

As described above, according to the present embodiment, when the strobe circuit 8 performs the charging operation at a predetermined value or more from the above procedure, at least one minute after the start of the charging operation.
Until the elapse of 2 minutes at the maximum, the battery check reference voltage is set lower than the normal reference voltage, so that batteries that have sufficient remaining capacity for normal operation and have temporarily dropped after charging are prohibited. And the operability can be improved.

On the other hand, if the battery is really depleted, even if the reference voltage is lowered temporarily after charging the strobe and checked, the operation is temporarily disabled because the battery voltage has dropped further. In addition, the user is notified that the remaining battery level is low, and if the battery level is further reduced, and if a maximum of 2 minutes have elapsed after charging the strobe, the operation inhibition state is determined based on the same reference value as a normal battery check. So
The reliability of the battery check is not impaired.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
The embodiment will be described with reference to the drawings. FIG. 6 is a flowchart of a film rewinding operation of the camera according to the second embodiment of the present invention. FIG. 7 is a flowchart of the operation when the operation switch of the camera shown in FIG. 6 is pressed. FIG. 8 is a flowchart of an operation when an interruption of the clock timer of the camera shown in FIG. 6 occurs.

The block diagram shown in FIG. 1 is common to the second embodiment. 2 and FIG. 3 are also common, and redundant description of the configurations in FIG. 1 and FIG. 2 is omitted.

In the first embodiment, only charging of a strobe is considered as a large load. However, in addition to the operation of the camera, the operation of energizing the motor and the like is a relatively large load, although smaller than charging the strobe circuit. In particular, in recent zoom cameras that have been downsized, the DC resistance of the motor tends to be reduced in order to obtain the same level of power of the motor as the downsized battery and downsized motor. The current at the time of energization is increasing.

In the second embodiment, the charging operation of the strobe is executed by paying attention to the charging operation of the strobe having the largest load in the operation of the camera and the rewinding operation of the film which is considered to have the next highest load. If so, the information is stored, and the reference voltage of the battery check is changed to a second reference voltage lower than the first reference voltage until a predetermined time after the execution has elapsed, and the film rewind operation is performed. In this case, the information is stored, and the reference voltage of the battery check is changed to a third reference voltage lower than the first reference voltage until a predetermined time has elapsed after the execution.

That is, if the battery check operation is performed again within a fixed time after the completion of the flash charging or within a fixed time after the execution of the film rewinding operation, the camera voltage is lowered to a battery voltage lower than the normal operation prohibition voltage. The operation is permitted.

In the second embodiment, A /
The D converter 2 is the same as that in the first embodiment, and the first reference voltage of the battery check is the same as that in the first embodiment.

Next, the operation will be described.

First, the flash charging operation is exactly the same as that of the first embodiment shown in FIG. 3, and therefore, the duplicate description will be omitted, and the operation at the time of film rewinding shown in the flowchart of FIG. 6 will be mainly described. I do.

When the number of shots reaches the specified number of films, or when the user presses the midway rewind button, the film rewind operation starts.

The current number of frames of the film before the start of rewinding is detected (S130). This is because these values are detected in the sense of detecting such a case because the load is not large when the number of rewinds is very small, such as when the rewind button is pressed halfway. is there.

Next, the number of frames to be rewound is calculated (S13).
1). That is, the number of frames to be rewound by the rewinding operation can be calculated from the specified number of films read at the time of loading the film and the current number of photographed films. If the number of frames is equal to or more than a predetermined number (for example, 15 or more in the second embodiment), it is determined that the load is large, and this state is stored.

That is, a predetermined bit of a predetermined address of the EEPROM 12 (this is rewinded by a predetermined amount of film b
is set to 1 (S132). On the other hand,
If the number of frames is equal to or less than the predetermined value, the film rewinding operation is started by driving the film feeding motor 9 by the film feeding means 10 without doing anything (S13).
3).

Next, it is determined whether or not the film has been normally rewound (S134). Actually, the film rewinding operation of the film is more strictly checked and displayed. However, since the operation is not directly related to the present invention, it is omitted here. If it is determined in S134 that the film has been normally rewound, the control of the film feeding means 10 is stopped, and the operation of the film feeding motor 9 is stopped (S134).
135).

Thus, the rewinding operation of the film is completed. Thereafter, the information display means 5 indicates that the rewinding operation has been completed, if necessary, and waits for the rewinding film to be taken out.

Next, the state after waiting for a switch operation will be described with reference to the flowchart of FIG.

Wait for the operation switch to change (S14)
0). At this time, the CPU 1 is set to accept an interrupt of the clock counter measured by the low-speed clock.

In this state, the operation switch changes, and C
When the PU1 is activated, a predetermined operation is performed according to the operated switch. In that case, first, a battery check is performed.

[0091] With a predetermined load being energized, the battery voltage is measured by the battery voltage detecting means 4 by A / D conversion (S141). Next, the result of the A / D conversion is compared with a reference voltage to determine whether or not to prohibit the operation. Before that, the information of the strobe charged bit of the EEPROM 12 is first read (S142).

It is determined whether the result of the strobe charged bit read from the EEPROM 12 is set to 1 (S143). If it is set to 1, it is determined that the flash has been charged immediately before and that the battery voltage has temporarily dropped, and the A / A
As the reference voltage to be compared with the D conversion result, 60H obtained by subtracting 10H from the first reference voltage 70H is set (S14).
5).

In this case, since the load due to the flash charging is greater than the load for rewinding the film, it is determined that the effect of rewinding the film is sufficiently small, and the rewind bit for the predetermined amount of the film is checked. Perform the following steps without performing

On the other hand, if the strobe charged bit remains 0, it is determined that the large load of the strobe charging has not been supplied immediately before, and the film rewind bit of a predetermined amount is checked (S144). ). Here, if the film rewind bit of the predetermined amount is 1, it is determined that the battery has been rewinded by a predetermined amount or more immediately before, and that the battery voltage has temporarily decreased somewhat, First
Is set to 68H by lowering the reference voltage from 70H (S1).
46). On the other hand, if the film rewind bit by the predetermined amount is 0, it is determined that the battery voltage is in a sufficiently steady state, and the first reference voltage 70H is used as the reference voltage (S147).

Thus, S145, S146, S147
Is compared with the battery voltage that has been previously A / D converted (S148). When 70H is set as the reference voltage, the operation inhibition voltage is set to 2.
Although it is 19V, when 60H is set as the reference voltage, (2.5V / 256) × 60H × 2 = 1.88V
And the operation inhibition voltage becomes 1.88V.

When 68H is set as the reference voltage, (2.5 V / 256) × 68H × 2 = 2.03
V and the operation inhibition voltage becomes 2.03V.

If the battery voltage is higher than any of the previously set reference voltages in step S148, it is determined that the camera is operable, and the camera is operated in accordance with the previously operated operation switch. Execute the sequence (S14)
9). If it is determined in step S148 that the battery voltage does not reach any of the reference voltages, it is determined that the camera does not function properly, and the information display unit 5 displays that the camera is in an operation-prohibited state, and then proceeds to step S140. Return to (S150).

Next, the processing when an interrupt is generated by the clock counter, which has been set earlier during this sequence, will be described with reference to the flowchart shown in FIG.

Now, the camera measures time using a low-speed oscillator, and displays clock information on the information display means 5. Therefore, when an interrupt of the clock counter occurs, the clock data stored in the RAM (not shown) and the elapsed time of the clock timer are added, and written again in the RAM (S16).
0).

Next, as a result of updating the clock data, it is determined whether or not the display means needs to be rewritten (S16).
1). Generally, clock information displays the date, time, date and time, and so on.In such a case, if the “minute” of the clock increases, the clock display on the display means must be updated. is there. Therefore, if an update is necessary, the display is updated (S162). Since the interrupt of the watch counter generally occurs in a time shorter than one minute, it is necessary to rewrite the display once every several tens of timer interrupts.

If the display needs to be updated, the strobe charged bit of the EEPROM 12 is updated every minute.
Then, it is determined whether or not 1 is set in the rewind bit of the film by a predetermined amount. That is, the flash-charged bit and the film rewind bit of the predetermined amount of the EEPROM 12 are read (S163), and it is determined whether or not any of the bits is set to 1 (S164).

Here, when none of the bits is set to 1, there is no history of charging the strobe just before or rewinding the film.
End the interrupt processing without doing anything. On the other hand, if any bit is set to 1, any bi
The elapsed bit, which records the elapsed time from the detection of t in a specific bit at a predetermined address of the EEPROM 12, is read (S165).

That is, if this elapsed bit is 0, one of the bits has been set to 1 after the previous timer interrupt, that is, within 1 minute after charging the strobe or within 1 minute after the film rewind operation. If the elapsed bit is 1, it can be determined that the elapsed time is 1 minute or more and 2 minutes or less, respectively.

Thus, it is determined whether the elapsed bit is 1 (S166). In the case of 1, since at least one minute has passed since the flash charging or the film rewinding, it is determined that the battery voltage has been recovered, and the flash charged bit or the film rewinding a predetermined amount of the bit has been completed.
Is reset to 0, and the elapsed bit is also reset to 0 (S167). If the elapsed bit is 0, it is determined that the battery voltage has not recovered yet because one minute has not yet elapsed, and the elapsed bit is set to 1 to wait for one minute to elapse and an interrupt is generated. Finish the processing (S16
8).

From the above procedure, when the strobe circuit executes the charging operation at a predetermined value or more, or when the film is rewound by a predetermined number or more, at least one minute after the start of each operation and up to two minutes at most. During this period, when the battery check reference voltage is lowered from the normal reference voltage in accordance with each operation, the battery has sufficient remaining capacity for normal operation, and temporarily drops after a large load is energized. For example, it is possible to reduce the probability of operation prohibition and improve operability.

On the other hand, if the battery is really exhausted,
Even if the reference voltage is lowered temporarily after the large load is energized, the battery voltage further drops, so the operation is temporarily disabled and the user is notified that the remaining battery level is low, and furthermore, If the state is lowered, if 2 minutes or more have passed after the large load is energized, the operation inhibition state is determined based on the same reference value as in the normal battery check, and finally the battery is checked. It will not be compromised.

(Third Embodiment) Next, a third embodiment of the present invention will be described.
The embodiment will be described with reference to the drawings. FIG. 9 is a block diagram of a camera according to the third embodiment of the present invention. FIG. 10 is a flowchart of the operation when the operation switch of the camera shown in FIG. 9 is operated. FIG. 11 shows FIG.
6 is a flowchart of an operation when an interruption of a watch timer of the camera shown in FIG.

In FIG. 9, reference numeral 15 denotes a battery type detecting means for determining the type of the battery loaded in the camera. The same components as those in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted.

Here, first, the battery type detecting means 15
The type of the battery loaded in the camera is determined. Some cameras use commonly used lithium batteries,
Alkaline batteries such as AA batteries can be used, small batteries that are used by mounting inside standard cameras,
By connecting a large battery outside the camera to the camera,
Since there is a type that can use an external battery preferentially, those types are identified first. In this embodiment, it is assumed that the system can use an external battery.

Also, the description will be made on the assumption that the characteristics of the A / D converter are the same as those of the first embodiment, and that the first reference voltage of the battery check is the same as that of the first embodiment.

Hereinafter, in the present embodiment, attention is paid only to the strobe charging operation having the largest load among the camera operations, and when the strobe charging operation is executed, the information is stored and a predetermined time after the execution is stored. Until elapses, the reference voltage of the battery check is changed to a reference voltage lower than the first reference voltage. When a small battery mounted inside a standard camera is used by the battery type detecting means, the reference voltage is converted to an A / D conversion value rather than the first reference voltage, as in the conventional example. When it is determined that an external large battery is used, it is determined that the voltage drop is smaller than that of the internal small battery, and the A / D conversion value is smaller than the first reference voltage. 8H is set to a smaller value.

On the other hand, as described in the first embodiment, the state of recovery of the battery voltage after supplying a large load greatly varies depending on the battery temperature.

Therefore, in the present embodiment, when the charging operation of the strobe is performed, the information is stored and the reference voltage of the battery check is lower than the first reference voltage until a certain time elapses after the execution. The temperature is changed to the reference voltage, and the constant time is measured by the temperature detecting means 3 to measure the environmental temperature, and the temperature is switched according to the result.

That is, if the temperature is room temperature or higher, it waits for one to two minutes to elapse. If the temperature is low, this time is extended to two to three minutes.

If the battery check operation is performed again within a certain period of time after the completion of the flash charging, the operation of the camera is permitted up to a battery voltage lower than a normal operation prohibition voltage. The comparison reference value of the battery voltage is switched according to the type of the battery.

Next, the operation will be described with reference to the flowchart of FIG.

In the camera sequence, for example,
The operation from the start of the flash charging sequence by pressing the release switch is the same as that described in the first embodiment with reference to FIG.

First, it waits for the operation switch to change (S170). At this time, the CPU 1 is set to accept an interrupt of the clock counter clocked by the low-speed clock. In this state, the operation switch changes,
When the CPU 1 is started, a predetermined operation is performed according to the operated switch.

The type of battery currently used by the camera is determined. It is determined whether the battery is an internal small battery or an external large battery according to the output of the battery type detection means 15 (S17).
1).

Next, a battery check is performed. here,
The battery voltage is measured by the A / D conversion by the battery voltage detecting means 4 in a state where a predetermined load is supplied (S172).

Next, the A / D value is compared with a reference voltage to determine whether or not operation is prohibited.
Read the information of the OM12's flash charged bit (S1
73).

The result read from the EEPROM 12 is 1
Is determined (S174). 0
If the battery voltage remains as it is, a large load such as charging of the strobe is not supplied immediately before, and it is determined that the battery voltage is in a sufficiently steady state, and is compared with the A / D conversion result of the battery voltage. The first reference voltage 70H
(S176).

If the value is set to 1, it is determined that the flash was charged immediately before and the battery voltage is temporarily lowered. Here, the determination result of the battery type is confirmed (S175). When the battery currently used is an internal battery, it is determined that the amount of voltage drop is large, and 60H obtained by subtracting 10H from the first reference voltage 70H is determined as a reference voltage to be compared with the A / D conversion result of the battery voltage. Set (S
177).

On the other hand, if it is determined that the battery currently used is an external battery, it is determined that the amount of voltage decrease is not so large, and the reference voltage to be compared with the A / D conversion result of the battery voltage is: 68H is set lower than the first reference voltage 70H (S178). Thus, S176, S17
7. The reference voltage set in S178 is compared with the battery voltage previously A / D converted (S179). Reference voltage is 7
In the case of 0H, the operation inhibition voltage has a value of 2.
In the case of 19V and 68H, it becomes 2.03V, and in the case of 60H, it becomes 1.88V.

If the battery voltage is higher than any of the previously set reference voltages, it is determined that the camera is operable, and the sequence of the camera corresponding to the previously operated operation switch is executed (S180). ).

If it is determined in S179 that the battery voltage does not reach any of the reference voltages, it is determined that the camera cannot function normally, and the information display means 5
Is displayed to indicate that the operation is prohibited, and the process returns to the operation switch waiting loop of S170 (S181).

Next, the processing in the case where an interrupt is generated by the previously set clock counter during this sequence will be described with reference to the flowchart of FIG.

The camera according to the present embodiment measures time using a low-speed oscillator and displays clock information on the information display means 5. Therefore, when the watch counter interrupts, R
The clock data stored in the AM (not shown) and the elapsed time of the clock timer are added and written in the RAM again (S190).

Next, as a result of updating the clock data, it is determined whether or not the display means needs to be rewritten (S19).
1). Generally, the clock information displays the date, time, date and time, so in such a case, it is necessary to update the clock display on the display means when the “minute” of the clock increases. is there. Therefore, the display is updated (S192). Also,
In this embodiment, when the display needs to be updated,
That is, the strobe charged in the EEPROM 12 every minute
It is determined whether 1 has been set to it. That is,
Read the strobe charged bit of the EEPROM 12 (S
193). It is determined whether the strobe charged bit is set to 1 (S194).

Strobe charged bit of EEPROM 12
However, if it is not set to 1, there is no history of charging the strobe just before, so the interrupt processing is terminated without doing anything. On the other hand, when the strobe charged bit is set to 1, the strobe charged bit is set.
The data (hereinafter, referred to as “elapsed data”) in which the elapsed time from the detection of the data is recorded at a predetermined address of the EEPROM is read (S195).

That is, if the elapsed data is 0,
After the previous timer timer interrupt, the flash-charged bit is set to 1 to indicate that it is within 1 minute after the flash is charged. If this elapsed data is 1, 1 minute or more and 2 minutes after the flash is charged Can be determined to be within
If it is 2, it can be determined that it is 2 minutes or more and 3 minutes or less after the flash charging. The temperature is measured to set the elapsed time (S196).

Therefore, the output of the temperature detecting means 3 is A / D converted, and based on this information, it is determined whether the ambient temperature is equal to or higher than the normal temperature. Here, it is determined whether the temperature is 0 ° C. or higher (S197).

If it is determined that the temperature is 0 ° C. or less, it is determined whether or not the elapsed data is 2 (S19).
8). If the elapsed data is 2, it means that at least 2 minutes have passed since the flash was charged.
It is determined that the battery voltage has sufficiently recovered even if the temperature is 0 ° C. or less, the elapsed data is set to 0, and the strobe charged bit is set to 0.
(S202).

If the elapsed data is not 2, the elapsed data is incremented and the process waits for the next timer interrupt (S201). As described above, when the strobe charged bit is set to 1 when the temperature is 0 ° C. or less, the strobe charged bit is set to 1 for at least 2 minutes.

If the temperature is 0 ° C. or more in S197, it is determined whether the elapsed bit is 1 or more (S199).

In the case of 1 or more, since at least one minute has elapsed since the strobe was charged, if the temperature is 0 ° C. or more, it is determined that the battery voltage has recovered, and the strobe charged bit
Is reset to 0, and the elapsed bit is reset to 0 (S2
00).

If the elapsed bit is 0, one minute has not yet elapsed, so that it is determined that the battery voltage has not recovered yet, and in order to wait for another one minute, the elapsed bi
t is incremented, and the interrupt processing ends (S20).
1).

In S 199, counting is performed until the elapsed data reaches 2 while the external battery is used, and when the battery is switched to the internal battery, the elapsed data remains at 2 and the process proceeds to S 199.
Since the determination in 199 may be made, it is determined whether the value is “1” or more. Then, when the strobe charged bit is set to 1 when the temperature is 0 ° C. or higher, the strobe charged bit is set to 1 for at least one minute.

According to such a third embodiment,
When the strobe circuit performs the charging operation at a predetermined value or more from the above procedure, if the temperature is high after the charging operation is started, at least 1 minute and up to 2 minutes elapse.
When the temperature is low, the reference voltage for the battery check is set lower than the normal reference voltage for at least two minutes and up to three minutes.

Further, when the internal small battery is used, the reference voltage at this time can be further controlled by lowering the reference voltage. Immediately after that, it is possible to reduce the probability of prohibiting the operation if it is only temporarily lowered, and to further improve the operability.

(Other Embodiments) For the sake of simplicity, only the reference voltage for the operation inhibition voltage has been described. However, the same method can be applied to the operation warning voltage. Of course.

In the present invention, the strobe charged bi
t, the film rewind bit by a predetermined amount, and the elapsed bit
Although stored in the PROM 12, a storage area inside the CPU 1 may be used. Even if the volatile memory that is not backed up by the battery loses the information only when the battery is replaced, it is sufficient for the use of the present invention.

Further, in the present invention, the time measurement is also performed by the clock timer of the camera for simplification of the software. Of course, by measuring the elapsed time after the execution of the predetermined operation accurately, Needless to say, more accurate control becomes possible.

In the present invention, the reference value is changed depending on whether or not the charging voltage before the start of flash charging is equal to or higher than a predetermined value. It is needless to say that finer control is possible by performing linear control.

In the present invention, the reference voltage is changed only for the strobe charging and the film rewinding operation. However, other operations having a large load (for example, searching for unexposed frames) can be performed. Similarly, it goes without saying that appropriate control is performed by changing the reference voltage according to the magnitude of each load.

Further, in the present invention, the comparison reference voltage is changed according to the temperature measurement data, and the reference voltage change time is changed according to the battery type detection result. Either parameter may be changed.

It is also possible to change the comparison reference voltage and the change time according to other measurement data, for example, the A / D conversion result of the battery voltage at the time when the strobe charged bit is 0. . That is, when the strobe completed bit is 0, the A / D of the battery voltage when the battery is fully recovered
Based on the result, it is determined how much the battery is depleted, and if the battery is depleted, the comparison reference voltage is reduced accordingly. Alternatively, control for increasing the change time is also possible.

[0148]

As described above, according to the first aspect of the present invention, the output of the reference voltage setting means is switched only for the time set by the time setting means according to the contents stored in the storage means. Thereby, the reliability of the battery check and the warning display can be enhanced, and a camera having excellent operability in consideration of the characteristics of the battery can be provided.

Further, according to the second aspect of the present invention, since one of the plurality of modes is a strobe charging operation, the reliability of the battery check and the warning display after the strobe charging operation is improved, and the characteristics of the battery are improved. It is possible to provide a camera with excellent operability considering the above.

Further, according to the third aspect of the invention, the output of the reference voltage setting means or the time setting means is varied according to the temperature, so that the reliability of the battery check and the warning display can be improved without being affected by the temperature. It is possible to provide a camera with improved operability and excellent operability in consideration of battery characteristics.

Further, according to the fourth aspect of the present invention, the outputs of the reference voltage setting means and the time setting means are made variable in accordance with the output of the battery voltage detecting means, so that the output is independent of the degree of battery consumption. The reliability of the battery check and the warning display can be enhanced, and a camera having excellent operability in consideration of the characteristics of the battery can be provided.

Further, according to the fifth or seventh aspect of the present invention, the outputs of the reference voltage setting means and the time setting means are made variable in accordance with the type of the battery, so that the output is independent of the type of battery used. The reliability of the battery check and the warning display can be enhanced, and a camera with excellent operability in consideration of the characteristics of the battery can be provided.

Further, according to the present invention, as information relating to the operation mode, a strobe charging bit, a predetermined amount of film winding bit and an elapsed bit are stored in the RAM.
, Accurate data for switching the outputs of the reference voltage setting means and the time setting means can be stored.

Further, according to the present invention, a battery check according to the state of the battery and an accurate warning display can be performed.

Further, according to the ninth aspect of the present invention, accurate battery check and warning display can be performed.

Further, according to the tenth aspect of the present invention,
The reference voltage can be set to one.

[Brief description of the drawings]

FIG. 1 is a block diagram of a camera according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a change in battery voltage of the camera shown in FIG.

FIG. 3 is a flowchart of an operation of the camera shown in FIG. 1 during flash charging.

FIG. 4 is a flowchart of an operation when an operation switch of the camera shown in FIG. 1 is pressed.

FIG. 5 is a flowchart of an operation when an interruption of a watch timer of the camera shown in FIG. 1 occurs.

FIG. 6 is a flowchart of a film rewinding operation of the camera according to the second embodiment of the present invention.

FIG. 7 is a flowchart of an operation when an operation switch of the camera shown in FIG. 6 is pressed.

FIG. 8 is a flowchart of an operation when an interruption of a watch timer of the camera shown in FIG. 6 occurs.

FIG. 9 is a block diagram of a camera according to a third embodiment of the present invention.

FIG. 10 is a flowchart of an operation when an operation switch of the camera shown in FIG. 9 is operated.

FIG. 11 is a flowchart of an operation when an interruption of a watch timer of the camera shown in FIG. 9 occurs.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CPU 2 A / D converter 3 Temperature detecting means 4 Battery voltage detecting means 5 Information display means 6 High-speed oscillator 7 Low-speed oscillator 8 Strobe circuit 9 Motor 10 Film feeding means 11 Exposure control means 12 EEPROM 13 Switch detecting means 14 DC / DC converter 15 Battery type detection means

Claims (10)

[Claims] A plurality of loads to be supplied with power from a battery; a plurality of operation modes for supplying a predetermined power to each of the loads; a battery voltage detecting means for detecting a voltage of the battery; A reference voltage setting means for setting a reference voltage value and a reference voltage value lower than the reference voltage value; a comparison means for comparing the detected battery voltage with the output of the reference voltage setting means; Storage means for storing information relating to the mode, timer means for measuring an elapsed time since execution of the operation mode of the immediately preceding camera, and time setting means for setting a time to be measured by the timer means, wherein the comparing means In a camera that prohibits operation or warns in accordance with the output of the above, switching the output of the reference voltage setting means only for the time set by the time setting means in accordance with the storage contents of the storage means. Features camera. 2. The camera according to claim 1, wherein one of the plurality of operation modes is a flash charging operation. 3. The camera according to claim 1, wherein an output of said reference voltage setting means or an output of said time setting means is variable according to a temperature. 4. The camera according to claim 1, wherein an output of said reference voltage setting means or an output of said time setting means is variable according to an output of a battery voltage detecting means. 5. The camera according to claim 1, wherein an output of said reference voltage setting means or an output of said time setting means is variable according to a type of a battery. 6. The information about the operation mode of the camera immediately before being stored in the storage means is a strobe charged bit indicating strobe charging, a film rewinding bit by a predetermined amount indicating film rewinding, and an elapsed bit indicating time lapse. The camera according to any one of claims 1 to 4, wherein: 7. The camera according to claim 5, wherein the type of the battery is detected by a battery type detecting means as an internal battery or an external battery. 8. An electronic apparatus having a load supplied with power from a battery, a voltage detecting means for detecting a voltage of the battery, and comparing the detected voltage with a first reference voltage to determine a battery state. Electronic equipment, wherein the reference voltage is set to a second reference voltage lower than the first reference voltage within a predetermined time after driving the load. 9. The electronic apparatus according to claim 8, wherein the reference voltage is set to a voltage higher than a second reference voltage after a predetermined time has elapsed. 10. The method according to claim 8, wherein setting the reference voltage to a second reference voltage is prohibited when the drive amount of the load is smaller than a predetermined amount according to the drive amount of the load. Or the electronic device according to 9.