JP4414531B2 - Electronic camera and battery level calculation method for electronic camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic camera that accurately calculates the remaining amount of a battery that supplies power, and a battery remaining amount calculation method for the electronic camera.
[0002]
[Prior art]
Conventionally, a battery is used as a power source for performing various operations of the camera. As the battery, a battery pack containing a plurality of cell batteries such as AA alkaline batteries, Ni-MH secondary batteries, or Li-ion batteries is used.
[0003]
FIG. 7 shows the discharge characteristics of a lithium battery generally used as a camera battery. This figure shows the temperature as a parameter when the horizontal axis represents the current consumption, the vertical axis represents the battery voltage when a predetermined load current is passed, and the specified load current is passed from the battery that consumed each current consumption. The battery voltage is plotted.
[0004]
Here, the voltage value V _INHB represents a voltage value at which the camera cannot operate normally below the voltage value. Then, a margin of ΔV _{M is added} to this voltage value V _INHB to determine a determination level V _LOCK for determining whether to allow camera operation. The upper limit of the V _LOCK level is limited by the standard for the number of shots that can be taken at low temperatures.
[0005]
By the way, as can be seen from FIG. 7, in the vicinity of the V _LOCK level designed as described above, the lower the temperature, the more the rate of change (drop rate) of the battery voltage with respect to the current consumption when a predetermined load current flows. On the other hand, the rate of change (falling rate) becomes large (the slope is stiff) at a low temperature (relative slope), while at a high temperature (room temperature or higher).
[0006]
For this reason, when the camera operation is permitted just _below the V _LOCK voltage, the current capacity until the battery voltage reaches V _INHB greatly varies depending on the temperature due to current consumption due to a defective operation, and decreases as the temperature increases (I _Cap1 and _ICap2 )
[0007]
Normally, V _LOCK is designed based on the low temperature side as described above. Therefore, there is a problem that current consumption is large and camera operation over a relatively long period of time becomes inoperative and interrupted. On the other hand, if the margin current capacity in the vicinity of V _LOCK at a high temperature is ensured, the margin at a low temperature becomes excessive, and the standard for the number of shots that can be taken at a low temperature cannot be satisfied.
[0008]
Therefore, conventionally, the voltage level of the V _LOCK is changed depending on the temperature so that the above problem does not occur. For example, as a method of changing the voltage level of V _LOCK depending on the temperature, a method of imparting temperature dependency to the battery check voltage using a plurality of resistors having different temperature coefficients is disclosed in Japanese Utility Model Publication No. 59-131567, This is disclosed in Japanese Utility Model Laid-Open No. 62-106165.
[0009]
Also, a method of having a temperature detection means and correcting the determination level based on the detected temperature information is disclosed in Japanese Patent Laid-Open Nos. 2-262278 and 3-180784.
[0010]
[Problems to be solved by the invention]
Electronic cameras capable of incorporating a plurality of types of batteries, such as AA batteries and battery packs incorporating a plurality of cell batteries, have been developed. However, since the AA battery and the battery pack have different heat generating parts, there is a problem that the temperature of the built-in battery cannot be measured accurately and the remaining battery charge cannot be calculated accurately.
[0011]
FIG. 8 shows the discharge characteristics of an alkaline battery, a Ni-MH battery, and a Li-ion battery. In the figure, the time change of voltage at the same temperature and the same load is measured.
[0012]
As shown in FIG. 8, the discharge characteristics vary depending on the type of battery. There is a problem that accuracy is poor depending on the type of battery, since the process for obtaining the remaining battery level is not performed according to the type of each battery.
[0013]
An object of the present invention is to provide an electronic camera that can accurately measure the temperature of a battery regardless of the type of battery.
[0014]
Another object of the present invention is to provide an electronic camera capable of accurately measuring the battery temperature and accurately measuring the remaining amount regardless of the type of battery, and a method for calculating the remaining battery level of the electronic camera.
[0015]
[Means for Solving the Problems]
[Constitution]
The present invention is configured as follows to achieve the above object.
[0016]
(1) An electronic camera according to the present invention (Claim 1) is an electronic camera that records video captured by an image sensor as digital data and can use a plurality of types of batteries, and includes a temperature detection unit. An external power input terminal to which the pack is connected, a battery that does not have temperature detecting means, or a battery mounting portion in which a battery having temperature detecting means is loaded, and temperature detection provided in the battery mounting portion Any one of the temperature detection means electrically connectable to the temperature detecting means of the battery pack, the temperature detecting means of the mounted battery, and the temperature detecting means provided inside the battery mounting portion. identification and temperature calculation means, the presence or absence of the connection of the connectable temperature detector to the temperature calculating unit, the battery type supplying power to calculate the temperature based on the temperature information detected by the means Including a battery identification unit, based on the identification result of the cell identification means, and a temperature information selection means for selecting whether said temperature calculation means which of the temperature detection means calculates the temperature based on the temperature information detected to It is characterized by becoming.
[0017]
(2) An electronic camera according to the present invention (Claim 2) is an electronic camera that records video captured by an image sensor as digital data and can use a plurality of types of batteries, and includes a temperature detection unit. An external power input terminal to which the pack is connected, a battery that does not have temperature detecting means, or a battery mounting portion in which a battery having temperature detecting means is loaded, and temperature detection provided in the battery mounting portion Any one of the temperature detection means electrically connectable to the temperature detecting means of the battery pack, the temperature detecting means of the mounted battery, and the temperature detecting means provided inside the battery mounting portion. identification and temperature calculation means, the presence or absence of the connection of the connectable temperature detector to the temperature calculating unit, the battery type supplying power to calculate the temperature based on the temperature information detected by the means A battery identification unit that, based on the identification result of the cell identification means, and the temperature information selection means for selecting whether to calculate the temperature said temperature calculation means based on the temperature information detected by the one of the temperature detecting means, wherein A remaining amount calculating unit for determining a remaining battery level based on the temperature calculated by the temperature calculating unit based on the temperature information selected by the temperature information selecting unit and the voltage of the battery identified by the battery identifying unit ; It is characterized by comprising.
[0018]
It is preferable that the temperature detection means provided inside the battery mounting portion is installed at a position corresponding to a position where the temperature of the battery not provided with the temperature detection means rises most.
[0019]
It is preferable that power is supplied to the electronic camera from a battery that is not inserted into the battery mounting portion and includes temperature detection means.
[0020]
(3) The battery remaining amount calculation method of the present invention ( Claim 6 ) has an external power input terminal that can be connected to a battery pack having a temperature detecting means, and the image captured by the image sensor is converted into digital data. The remaining battery level of an electronic camera comprising: a recording means; a battery having a temperature detection means or a battery insertion portion having a temperature detection means provided therein, and a battery not having a temperature detection means inserted therein Any one of the temperature detection means of the battery pack, the temperature detection means of the battery inserted in the battery insertion portion, and the temperature detection means provided inside the battery mounting portion is a calculation method. Identifying the type of battery supplying power from the temperature detection means connected to the temperature calculation means for calculating the temperature based on the temperature information detected by the temperature detection means; , Based on the identified cell, and calculates the temperature based on the steps of the temperature calculation means selects either temperature calculation, the selected temperature information by using the temperature information detected by any of the temperature detecting means A step of reading from a memory with built-in table data indicating a remaining battery level with respect to a temperature and a voltage value related to the battery supplying the power, and the calculation from the table data, the selected temperature, and the voltage of the identified battery. Determining the remaining battery level from the identified temperature and the voltage of the identified battery .
[0021]
[Action]
The present invention has the following operations and effects by the above configuration.
[0022]
A temperature detection means is provided in the battery insertion section, and a battery having a temperature detection means can be inserted in the battery insertion section, and temperature information detected by any of the temperature detection means is selected based on a battery supplying power. By doing so, temperature measurement according to the type of battery becomes possible, and the temperature of the battery can be accurately measured.
[0023]
In addition, the temperature of the battery can be accurately measured by the above-described method, and the remaining amount of the battery that supplies power can be accurately known by calculating the remaining amount of the battery according to the type of battery that supplies power. it can.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0025]
FIG. 1 is a block diagram showing a schematic configuration of an electronic camera according to an embodiment of the present invention.
[0026]
As shown in FIG. 1, an image projected onto the image sensor 12 via the imaging lens system 11 is converted into digital data via the imaging circuit 13 and the A / D converter 14. The converted image data is temporarily stored in the buffer memory 15 and the data amount is compressed by the compression / expansion circuit 16. The image data compressed by the compression / decompression circuit 16 is recorded in the removable memory 19 attached to the card slot 18 via the I / F 17. Depending on the recording mode, the image data may be recorded in the removable memory 19 without being compressed by the compression / decompression circuit 16. The image data recorded in the removable memory 19 is transmitted to an external device such as a personal computer or a printer connected to the external input / output terminal 21 via the external I / F 20. The image input to the image sensor 12 and the image stored in the removable memory 19 and expanded by the compression / expansion circuit 16 are displayed on the image display LCD 24 via the video memory 22 and the video output circuit 23. Note that the above-described image can be displayed on a home television via the video-out terminal 25.
[0027]
In addition, information set by the operation unit, release, mode setting, and battery display selection unit 26 is transmitted to a system controller (battery identification means, temperature information selection means, remaining amount calculation means) 27. The system controller 27 performs display control of the mode LCD 28 in which the battery remaining amount display and various setting items or selection items are displayed. Further, the strobe light emitting unit 29 emits light according to a command from the system controller 27 according to the brightness.
[0028]
The electric power supplied from the internal battery inserted into the internal battery insertion part (battery mounting part) or the external power input terminal is supplied to the system controller 27 and the camera circuit via the power supply part 30.
[0029]
As a built-in battery inserted into the built-in battery insertion section, there is a pack battery 33 incorporating a cell battery 34 such as an AA alkaline battery (primary battery), a Ni-MH battery, or a plurality of lithium batteries. A thermistor 32 is disposed on the side surface of the internal battery insertion portion. As shown in FIG. 2, the thermistor 32 provided in the built-in battery insertion portion 51 is a position where the temperature of the alkaline battery (primary battery) or the Ni-MH battery (secondary battery) of the AA battery 31 rises most. Is provided at a position corresponding to the center of the AA battery 31. In addition, although the site | part where the temperature of AA type | mold battery 31 rises is a center part inside a battery, since it cannot measure from the outside, the thermistor 32 is set in the position corresponding to the center part of AA type | mold battery 31. It is arranged.
[0030]
As a voltage source supplied from an external input terminal, there are a battery pack 37 incorporating a large-capacity cell battery 38 and an AC adapter 41 for transforming a household power source.
[0031]
Further, in the battery pack 33 and the battery pack 37 for storing a plurality (n) of cell batteries 38, thermistors 35 and 39 for measuring the temperature of the battery cells to be stored, and pack-specific information are recorded. The memories 36 and 40 are provided. The thermistors 35 and 39 in the battery pack 33 and the battery pack 37 are arranged in a space between adjacent cell batteries where heat generated from the cell batteries 34 and 38 is likely to be trapped. For example, as shown in FIG. 3, in the case of a battery pack including four cell batteries, a thermistor is arranged at the center of the four cell batteries.
[0032]
The pack-specific information stored in the memories 36 and 40 includes voltage, capacity, number of times of charging / discharging, date of charging / discharging, and the like. Further, in the memories 36 and 40, a table (FIG. 4) indicating the remaining battery capacity with respect to the temperature and the voltage value is stored.
[0033]
In the case of the battery pack 37, the power line, the signal line connected to the thermistor, and the signal line connected to the memory are bundled into one input / output pin, and power and signals are transferred from the external power input terminal to the electronic camera.
[0034]
The temperature calculation circuit (temperature information selection means) 42 is one of the thermistor 32, the pack battery, or the thermistors 35 and 39 of the battery pack installed in the built-in battery insertion unit, depending on the power supply source supplied to the power supply unit 30. The temperature is calculated from the resistance value, and the measured temperature is transferred to the system controller 27.
[0035]
The system controller 27 includes the measured temperature and voltage value, the remaining battery level with respect to the temperature and voltage registered in advance, or the remaining battery level with respect to the temperature and voltage registered in the memory of the battery pack 33 or the battery pack 37. The remaining battery level of the battery to which power is supplied is calculated, and the result is displayed on the image display LCD 24 or the mode LCD 28.
[0036]
Next, a procedure for calculating the remaining amount of the battery will be described.
[0037]
5 and 6 are flowcharts showing the steps of the battery remaining capacity measuring method according to the embodiment of the present invention.
[0038]
First, the system controller 27 identifies whether power is supplied from the external power input terminal, and determines whether the power supplied to the camera body is supplied from the built-in battery inserted in the built-in battery insertion unit. (Step S1). When it is determined that power is not supplied from the built-in battery, it is determined whether the power supply source is the battery pack 37 based on whether or not the thermistor is connected to the temperature calculation unit (step S2).
[0039]
When power is supplied from the battery pack 37, the system controller 27 selects to measure the temperature from the resistance value (temperature information) of the thermistor 39 in the battery pack 37 (step S3). Next, the system controller 27 instructs the temperature calculation circuit 42 to measure the temperature using the thermistor 39 in the battery pack 37. Next, the temperature calculation circuit 42 measures the resistance value of the thermistor 39 in the battery pack 37 to measure the temperature of the cell battery 38, and transfers the measurement result to the system controller 27 (step S4). Next, the system controller 27 instructs the power supply unit 30 to measure the voltage supplied from the battery pack 37. The power supply unit 30 measures the voltage of the battery pack 37 and transfers the measurement result to the system controller 27 (step S5).
[0040]
Next, the system controller 27 reads a table indicating the remaining battery level with respect to the temperature and voltage value stored in the memory 40 in the battery pack 37 (step S6), and the read table and the measured voltage value and temperature value. Then, the remaining battery level is calculated (step S7), and the remaining battery level measurement routine is stopped (END).
[0041]
If it is determined in step S2 that power is not supplied from the battery pack 37, it is determined that power is supplied from the AC adapter 41, and the battery remaining amount measurement routine is stopped (END).
[0042]
If it is determined in step S1 that power is supplied from the built-in battery, the system controller 27 determines whether the built-in battery inserted in the built-in battery insertion unit is a pack battery based on whether or not the thermistor is connected to the temperature calculation unit. It is determined whether it is 33 (step S8). When it is determined that the battery inserted in the internal battery insertion portion is a battery pack, the system controller 27 selects to measure the temperature from the resistance value (temperature information) of the thermistor 35 in the battery pack 33 (step). S9). Next, the system controller 27 instructs the temperature calculation circuit 42 to measure the temperature using the thermistor 35 in the battery pack 33. Next, the temperature calculation circuit 42 measures the resistance value of the thermistor 35 in the battery pack 33 to measure the temperature of the cell battery 34, and transfers the measurement result to the system controller 27 (step S10). Next, the system controller 27 instructs the power supply unit 30 to measure the voltage supplied from the battery pack 33. The power supply unit 30 measures the supplied voltage and transfers the measurement result to the system controller 27 (step S11).
[0043]
Next, the system controller 27 reads a table indicating the remaining battery capacity with respect to the temperature and voltage value stored in the memory 36 in the battery pack 33 (step S12), and the read table and the measured voltage value and temperature value. Then, the remaining battery level is calculated (step S7), and the remaining battery level measurement routine is stopped (END).
[0044]
If it is determined in step S8 that the battery pack 33 is not inserted, it is assumed that power is supplied from the AA battery 31 in the built-in battery insertion section, and the system controller 27 sends the temperature calculation circuit 42 to the internal battery insertion section. The temperature is measured using the thermistor 32 (step S13). Next, the temperature calculation circuit 42 measures the resistance value of the thermistor 32 in the built-in battery insertion portion to measure the temperature of the AA battery 31 and transfers the measurement result to the system controller 27 (step S14). Next, the system controller 27 instructs the power supply unit 30 to measure the voltage supplied from the AA battery 31. The power supply unit 30 measures the voltage of the AA battery 31 and transfers the measurement result to the system controller 27 (step S15).
[0045]
Next, the system controller 27 determines whether the AA battery 31 inserted in the built-in battery insertion unit is a Ni-MH battery from the voltage supplied from the AA battery (step S16). If the supplied voltage is 4.8V (= 1.2 [V / book] × 4 [book]), it is determined that the AA battery is a Ni-MH battery, and 6V (= 1.5 [= 1.5 [book]). V / book] × 4 [book]), it is determined that the AA battery is an alkaline battery.
[0046]
When it is determined that the Ni-MH battery is inserted, the system controller 27 reads out a table indicating the remaining battery level with respect to the temperature and voltage value related to the Ni-MH battery registered in the main body (step S17). The remaining battery level is calculated from the obtained table and the measured voltage value and temperature value (step S7), and the remaining battery level measurement routine is stopped (END).
[0047]
In step S16, when it is determined that the Ni-MH battery is not inserted, it is determined that the alkaline battery is inserted, and the system controller 27 determines the temperature and voltage values related to the alkaline battery registered in the main body. A table indicating the remaining battery level is read (step S18), the remaining battery level is calculated from the read table and the measured voltage value and temperature value (step S7), and the remaining battery level measurement routine is stopped (END). .
[0048]
After the above battery remaining amount processing routine is completed, the system controller 27 displays the calculated battery remaining amount on the image display LCD 24 or the mode LCD 28.
[0049]
As described above, according to the present embodiment, the thermistor is provided in the battery insertion portion, the thermistor is also provided in the battery pack, and any one of the thermistors is used according to the battery that supplies power by the temperature calculation circuit. By calculating the temperature of the battery that supplies power, it becomes possible to measure the temperature according to the type of battery, and the temperature of the battery that supplies power can be accurately calculated.
[0050]
In addition to accurately measuring the temperature of the battery by the method described above, the system controller calculates the remaining amount of the battery according to the type of the battery that supplies the power, thereby accurately determining the remaining amount of the battery that supplies the power. I can know.
[0051]
The present invention is not limited to the above embodiment. For example, the temperature may be calculated from the resistance value of the thermistor in the battery pack, and the calculated temperature may be transferred as digital data to the temperature calculation circuit.
[0052]
In addition, when a battery pack that does not have a temperature detection means is inserted into the battery insertion portion, the temperature is measured using a thermistor in the battery insertion portion, and the remaining amount of the battery is calculated using a table stored in the main body. Can do.
[0053]
In addition, the present invention can be variously modified and implemented without departing from the scope of the invention.
[0054]
【The invention's effect】
As described above, according to the present invention, the battery insertion portion is provided with the temperature detection means, and the battery insertion portion can be inserted with the battery having the temperature detection means therein, and either one of the batteries is supplied based on the power supply. By selecting the temperature information detected by the temperature detecting means, it is possible to measure the temperature according to the type of the battery, and to accurately measure the temperature of the battery.
[0055]
In addition, the temperature of the battery can be accurately measured by the above-described method, and the remaining amount of the battery that supplies power can be accurately known by calculating the remaining amount of the battery according to the type of battery that supplies power. it can.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of an electronic camera according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a schematic configuration of a built-in battery insertion portion of an electronic camera according to an embodiment of the present invention.
FIG. 3 is a diagram showing a schematic configuration of a battery pack according to an embodiment of the present invention.
FIG. 4 is a table showing a remaining battery level with respect to a temperature and a voltage value according to an embodiment of the present invention.
FIG. 5 is a flowchart showing steps of a battery remaining amount measuring method according to an embodiment of the present invention.
FIG. 6 is a flowchart showing steps of a battery remaining amount measuring method according to an embodiment of the present invention.
FIG. 7 is a graph showing discharge characteristics of a lithium battery.
FIG. 8 is a graph showing discharge characteristics of an alkaline battery, a Ni-MH battery, and a Li-ion battery.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Imaging lens system 12 ... Imaging element 13 ... Imaging circuit 14 ... A / D converter 27 ... System controller (battery identification means, temperature information selection means, remaining amount calculation means)
30 ... Power supply 31 ... AA battery 32 ... Thermistor (temperature detection means)
33 ... Pack batteries 34, 38 ... Cell batteries 35, 39 ... Thermistor (temperature detection means)
36, 40 ... Memory 37 ... Battery pack 39 ... Thermistor (temperature detection means)
40 ... Memory 41 ... AC adapter 42 ... Temperature calculation circuit (temperature information selection means)
51 ... Built-in battery insertion part (battery mounting part)

Claims (7)

An electronic camera that records video captured by an image sensor as digital data and can use multiple types of batteries,
An external power input terminal to which a battery pack having temperature detecting means is connected;
A battery mounting portion in which a battery not having a temperature detection means or a battery having a temperature detection means is loaded;
Temperature detecting means provided inside the battery mounting portion;
The battery pack temperature detecting means, the temperature detecting means of the attached battery, and the temperature detecting means provided inside the battery mounting portion can be electrically connected, and detected by any one of the temperature detecting means. Temperature calculating means for calculating the temperature based on the temperature information to be performed;
Battery identification means for identifying the type of battery to supply power from the presence or absence of connection of a temperature detection means connectable to the temperature calculation means ;
Based on the identification result of the cell identification means, characterized in that said temperature calculation means which of the temperature detecting means is formed by and a temperature information selection means for selecting whether to calculate the temperature based on the temperature information detected And an electronic camera. An electronic camera that records video captured by an image sensor as digital data and can use multiple types of batteries,
An external power input terminal to which a battery pack having temperature detecting means is connected;
A battery mounting portion in which a battery not having a temperature detection means or a battery having a temperature detection means is loaded;
Temperature detecting means provided inside the battery mounting portion;
The battery pack temperature detecting means, the temperature detecting means of the attached battery, and the temperature detecting means provided inside the battery mounting portion can be electrically connected, and detected by any one of the temperature detecting means. Temperature calculating means for calculating the temperature based on the temperature information to be performed;
Battery identification means for identifying the type of battery to supply power from the presence or absence of connection of a temperature detection means connectable to the temperature calculation means ;
Based on the identification result of the cell identification means, and the temperature information selection means for selecting whether to calculate the temperature said temperature calculation means based on the temperature information detected by the one of the temperature detecting means,
A remaining amount calculating means for determining the remaining amount of the battery based on the voltage of the battery identified temperature calculated by said temperature calculation means based on the temperature information selected by said temperature information selection means by the cell identification means An electronic camera comprising: A memory for storing, for each battery type, table data indicating a remaining battery level with respect to a temperature and a voltage value related to the mounted battery;
The remaining amount calculating means determines the remaining amount of the battery from the table data read from the memory, the temperature calculated from the selected temperature information, and the voltage of the battery supplying the power. The electronic camera according to claim 1 or 2. 4. The electronic device according to claim 3 , wherein the temperature detection means provided in the battery mounting portion is installed at a position corresponding to a position where the temperature of the battery not provided with the temperature detection means rises most. camera. The battery identification means identifies the type of battery to be supplied from the battery pack, a battery not equipped with the temperature detection means, or a battery equipped with the temperature detection means. Item 5. The electronic camera according to any one of Items 4 above. An external power input terminal that can be connected to a battery pack having temperature detection means, means for recording video captured by the image sensor as digital data, a battery having temperature detection means, or a temperature detection means A battery remaining amount calculation method for an electronic camera including a battery insertion portion in which a battery is inserted and a temperature detection means is provided therein,
Among the temperature detection means of the battery pack, the temperature detection means of the battery inserted into the battery insertion portion, and the temperature detection means provided inside the battery mounting portion, by any one of the temperature detection means connected Identifying the type of battery supplying power from the temperature detection means connected to the temperature calculation means for calculating the temperature based on the detected temperature information ;
A step of based on the identified cell, the temperature calculation means selects either temperature calculation using the temperature information detected by any of the temperature detecting means,
Calculating a temperature based on the selected temperature information;
Reading from the table data built-in memory indicating the remaining battery capacity with respect to the temperature and voltage values for the battery supplying the power;
An electronic camera comprising: a step of obtaining a remaining battery level from the table data, the selected temperature and the voltage of the identified battery, and the calculated temperature and the voltage of the identified battery . Battery level calculation method. 7. The battery remaining amount calculation for an electronic camera according to claim 6, wherein the battery to be supplied is identified from the battery pack, a battery not provided with the temperature detection means, or a battery provided with the temperature detection means. Method.

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