JP2006162402A - Device and method for determination of battery residual capacity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly determine the end stage, even when any one of a plurality of batteries of different kinds is used. <P>SOLUTION: The control part 25 detects the voltage (the 1st voltage) of the battery 35, when no current is fed to a specific load attended with a photographing action, and the voltage (the 2nd voltage) of the battery 35, when the current is fed to the specific load, calculates the difference voltage, and determines the residual capacity of the battery 35 by comparing the calculated different voltage and the previously set reference voltage. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a remaining battery level determination device and a remaining battery level determination method for a device such as a digital camera that uses a battery as a power source.

  In general, portable electronic devices such as a digital camera, a mobile phone, and a PDA (personal digital assistant) can operate using a battery (dry battery) as a power source. Such an apparatus is provided with a function of detecting the remaining battery level and notifying the user.

  Conventionally, as a method for detecting the remaining battery level, it is determined that the remaining battery level is low when the battery voltage is measured and this voltage value becomes a specified value or less.

  For example, the battery voltage value is measured, the battery voltage drop value due to the current increase until the circuit stabilizes immediately after the operation mode of the device is changed, and the battery remaining amount is detected by this measured drop value. A warning circuit is considered (for example, Patent Document 1).

In addition to alkaline batteries, nickel metal hydride batteries, and nickel cadmium batteries, in recent years, nickel oxyhydroxide, new manganese dioxide, and new graphite are used for the positive electrode to maintain a higher voltage than conventional alkaline batteries. Batteries that can be continued (hereinafter referred to as high voltage holding batteries) have also been used. These various batteries have different discharge curve voltage characteristics that change with use depending on the type. For example, FIG. 4 shows characteristics of a general discharge curve of an alkaline battery or the like and characteristics of a discharge curve of a high voltage holding battery.
JP 2004-37299 A

  Thus, in the past, the battery voltage value was measured to determine the remaining battery level, but as shown in FIG. 4, the voltage characteristics differ depending on the type of battery, so that the battery cannot be used. In some cases, the end-stage determination for determining this cannot be properly performed.

  For example, as shown in the characteristics shown in FIG. 4, in an alkaline battery or the like, the voltage value suddenly decreases from the start of use, but the stable state continues at a voltage of 2.0 V or higher, and the voltage value gradually decreases even at 2.0 V or lower. Will go down. On the other hand, in a high voltage holding battery, a high voltage can be kept from the start of use as compared with an alkaline battery or the like, but at 2.0 V or less, the voltage value rapidly decreases.

  Therefore, if the reference voltage value for determining the end stage is 2.0 V, the battery voltage is rapidly increased even if the zoom lens is extended in a digital camera, for example, when the end stage determination is performed with an alkaline battery. Therefore, the lens can be stored after the end stage determination. On the other hand, in the high-voltage holding battery, since the voltage value suddenly drops at the end of the determination, the operation for retracting the lens cannot be executed, and the operation is performed with the lens extended. There was a risk of stopping.

  On the other hand, assuming that such a high voltage holding battery is used, for example, if the reference voltage value is 2.2 V, the operation is stopped after the lens is accommodated after the final stage determination even when the high voltage holding battery is used. Can be made. However, in this case, an alkaline battery or the like reaches 2.2 V at an early stage, so that it is determined as the end stage despite the remaining battery level.

  An object of the present invention is to provide a battery remaining amount determining device and a battery remaining amount determining method capable of appropriately determining the end of life regardless of which of a plurality of types of batteries having different characteristics is used. is there.

The invention according to claim 1 is a battery remaining amount determining device for determining a remaining amount of a battery.
First detection means for detecting the voltage value of the battery when current supply to the specific load is not performed, and second detection for detecting the voltage value of the battery when current supply to the specific load is performed Means for calculating a difference between the first voltage value detected by the first detection means and the second voltage value detected by the second detection means, and the voltage value calculated by the calculation means And determining means for determining the remaining battery level based on a preset reference value.

  According to a second aspect of the present invention, in the first aspect of the invention, the first aspect includes a determination unit that determines an instruction to start current supply to the specific load, and the first detection unit responds to the determination by the determination unit. The voltage value immediately before the current supply to the specific load is started is detected.

  According to a third aspect of the present invention, in the first aspect of the invention, the first detection unit detects a voltage value before and after supplying the current to the specific load, and the second detection unit detects a current to the specific load. The voltage value is detected a plurality of times during supply, and the calculating means calculates the average of the voltage values detected by the first detecting means and the average of the voltage values detected by the second detecting means. The difference is calculated.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, the determination condition recording means for recording a reference value based on the determination by the determination means for each of a plurality of battery types, and the determination means include the determination The remaining battery level is determined based on a reference value recorded by the condition recording unit according to the battery to be determined.

  The invention according to claim 5 is the invention according to claim 4, further comprising type information input means for inputting type information indicating the type of battery, wherein the determination means is the type information input by the type information input means. The remaining battery level is determined based on the reference value recorded by the determination condition recording means corresponding to the above.

  According to a sixth aspect of the present invention, in the fourth aspect of the present invention, an initial voltage value detecting unit that detects an initial voltage value of the battery, and a predetermined time has elapsed since the voltage value was detected by the voltage value detecting unit. And a voltage value detecting means for measuring a voltage value after being measured, and a difference between a voltage value detected by the initial voltage value detecting means and a voltage value detected by the voltage value detecting means after the elapse. Battery type discriminating means for discriminating the type of battery, wherein the judging means is a battery based on the reference value recorded by the judgment condition recording means corresponding to the type discriminated by the battery type discriminating means. The remaining amount is determined.

  According to a seventh aspect of the present invention, in the first aspect of the invention, the determination means determines the remaining battery level based on a reference value for determining a currently required remaining battery level. Features.

  According to an eighth aspect of the present invention, in the digital camera driven by a battery, first detection means for detecting a voltage value of the battery when the shutter is not driven, and the battery when the shutter is driven Second detection means for detecting a voltage value of the first detection means, calculation means for calculating a difference between the first voltage value detected by the first detection means and the second voltage value detected by the second detection means, And determining means for determining the remaining battery level based on a voltage value calculated by the calculating means and a preset reference value.

  The invention according to claim 9 is a battery remaining amount determining method for determining the remaining amount of the battery, the first detecting step of detecting the voltage value of the battery when the current is not supplied to the specific load; A second detection step for detecting a voltage value of the battery when supplying a current to the specific load; a first voltage value detected by the first detection step; and a detection by the second detection step. A calculation step for calculating a difference from the second voltage value, and a determination step for determining the remaining battery level based on the voltage value calculated in the calculation step and a preset reference value. Features.

  According to the first, eighth, and ninth aspects of the present invention, the voltage of the stable battery that is not supplying current to the specific load and the voltage value of the battery that is lowered by supplying current to the specific load Since the remaining amount is determined based on the difference, a battery that cannot determine the end state by simply using the voltage value of the battery, using the characteristics of the discharge curve that varies depending on the battery type and the voltage drop near the end. Also, the remaining amount can be correctly determined.

  According to the second aspect of the present invention, in addition to the effect of the first aspect of the invention, when it is determined that there has been an instruction to start current supply to the specific load, for example, a shutter operation in the digital camera, the shutter drive is performed. By detecting the voltage value immediately before the current supply to the load for the battery is started, it is only necessary to detect the voltage value at the timing necessary for determining the remaining battery level. There is no risk of increasing.

  According to the third aspect of the present invention, in addition to the effect of the first aspect of the invention, the voltage value detected before and after the current is supplied to the specific load, and a plurality of times detected when the current is supplied to the specific load. The remaining battery level is determined based on the average value of each voltage value, so it is possible to reduce the influence of fluctuations in the voltage value that appears instantaneously and to determine the stable remaining battery level. it can.

  According to the invention of claim 4, in addition to the effect of the invention of claim 1, a reference value for determination is recorded for each type of a plurality of batteries, and the reference according to the battery to be determined By determining the remaining amount of the battery based on the value, it is possible to determine the remaining amount of the battery more stably using the characteristics according to the type of the battery.

  According to the fifth aspect of the invention, in addition to the effect of the fourth aspect of the invention, it is possible to input the type information indicating the type of the battery, so that, for example, the user designates the type of the battery attached to the apparatus. Thus, it is possible to set a reference value used for determining the remaining battery level.

  According to the invention of claim 6, in addition to the effect of the invention of claim 4, the initial voltage value of the battery and a predetermined time have elapsed by utilizing the fact that the characteristics of the discharge curve are different in different types of batteries. Based on the difference from the subsequent voltage value, the type of battery used can be determined, and a reference value used for determining the remaining battery level can be set.

  According to the seventh aspect of the invention, in addition to the effect of the first aspect of the invention, the remaining battery level can be determined based on the reference value for determining the currently required remaining battery level. For example, when a zoom lens is being extended in a digital camera, it is possible to determine the end of the battery while leaving the remaining battery capacity to accommodate the zoom lens, and the zoom lens cannot be operated when it is extended. Can be avoided.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a camera apparatus 1 that realizes a battery remaining amount determination apparatus according to an embodiment of the present invention. The camera device 1 is a digital still camera, for example, and can operate using a battery as a power source.

  In the camera apparatus 1 shown in FIG. 1, in the photographing mode which is the basic mode, the photographing lens 11 is moved to the lens position corresponding to the aperture position or the normal photographing by driving the motor (M) 10 in the lens optical system. Further, the photographing lens 11 is extended / stored by driving a motor (not shown) according to the zoom operation. A CCD (Charge Coupled Device) 12, which is an image sensor disposed behind the photographing optical axis of the photographing lens 11, is scanned and driven by a timing generator (TG) 13 and a vertical driver 14, and is formed at regular intervals. The photoelectric conversion output corresponding to is output for one screen.

  The photoelectric conversion output is appropriately gain-adjusted for each primary color component of RGB in the state of an analog value signal, sampled and held by a sample hold (S / H) circuit 15, and digital data by an A / D converter 16. The color process circuit 17 further performs color process processing including pixel interpolation processing and gamma correction processing to generate a digital luminance signal Y and color difference signals Cb, Cr, and a DMA (Direct Memory Access) controller. 18 is output.

  The DMA controller 18 once uses the luminance signal Y and the color difference signals Cb and Cr output from the color process circuit 17 by using the composite synchronization signal, the memory write enable signal, and the clock signal from the color process circuit 17 once. And the DMA transfer to the DRAM 21 used as a buffer memory through the DRAM interface (I / F) 20.

  The control unit 25 includes a CPU, a ROM in which operation programs executed by the CPU, data, and the like are fixedly recorded, a RAM used as a work memory, and the like, and controls the entire camera device 1. . For example, the control unit 25 can execute a process for determining the remaining amount of the battery 35 used as a power source by executing a remaining battery level determining process according to the remaining battery level determining process program.

  After completing the DMA transfer of the luminance and color difference signals to the DRAM 21, the control unit 25 reads the luminance and color difference signals from the DRAM 21 via the DRAM interface 20 and writes them to the VRAM 27 via the VRAM controller 26.

  The digital video encoder 28 periodically reads luminance and color difference signals from the VRAM 27 via the VRAM controller 26, generates a video signal based on these data, and outputs the video signal to the display unit 29.

  The display unit 29 functions as a monitor display unit (electronic finder) in the shooting mode, and performs display based on the video signal from the digital video encoder 28 to display image information captured from the VRAM controller 26 at that time. The base image (through image) is displayed in real time.

  When a through image is displayed in real time on the display unit 29, a trigger signal is generated when the shutter key of the key input unit 37 is operated at the timing of capturing a still image.

  In response to this trigger signal, the control unit 25 stops driving the CCD 12 at that time, and then performs an automatic exposure process to obtain an appropriate exposure value, and controls the aperture of the lens optical system and the exposure time of the CCD 12. Re-capture the image.

  After the newly obtained image data for one frame is DMA-transferred and written in the DRAM 21 in this way, the control unit 25 reads out the image data for one frame written in the DRAM 21 to the image processing unit 30. Write. The image processing unit 30 encodes image data by JPEG (Joint Photographic Experts Group) with respect to the image data.

  The encoded image data is written to the memory card 32 that is detachably mounted as a recording medium of the camera device 1 or to the built-in memory 33 that is fixedly built when the memory card 32 is not mounted. .

  Then, with the completion of the writing of the image data to the memory card 32 or the built-in memory 33 for one frame, the control unit 25 resumes the drive for displaying the through image from the CCD 12 via the DRAM 21 on the display unit 29. .

  The control unit 25 is connected to a power control unit 34, a key input unit 37, an audio processing unit 40, and a strobe driving unit 41.

  The power control unit 34 performs control for supplying power from the battery 35 to each unit under the control of the control unit 25.

  The battery 35 is a power source for operating each part, and various types of batteries can be used. For example, in addition to an alkaline battery, a nickel metal hydride battery, a nickel cadmium battery, etc., a high voltage holding battery using nickel oxyhydroxide, new manganese dioxide and new graphite as the positive electrode can be used. This high-voltage holding battery keeps the voltage value higher than that of alkaline batteries, etc., but when a large current flows near the end of the battery (when the remaining battery level is low), the voltage value drops ( (Drop) has a large characteristic (see FIGS. 3 and 4).

  The A / D conversion unit 36 is connected to the battery 35 and outputs data indicating the voltage value of the battery 35 to the control unit 25.

  The control unit 25 acquires the voltage value of the battery 35 through the A / D conversion unit 36 in the battery remaining amount determination process according to the battery remaining amount determination processing program, and based on this voltage value and a preset reference value. Then, the remaining amount of the battery 35 is determined (term determination). The control unit 25 records and holds the reference value data used in the remaining battery level determination process for each type of the plurality of batteries used in the camera device 1 in the memory as the determination condition table 25a (third embodiment). Form).

  The key input unit 37 includes a power key, a shutter key, a mode switch, a menu key, a selection key, a cross key (cursor key), and the like, and signals associated with these key operations are sent directly to the control unit 25. The

  The audio processing unit 40 includes a sound source circuit such as a PCM sound source, digitizes the audio signal input from the microphone unit (MIC) 42 when recording audio, and performs a predetermined data file format such as MP3 (MPEG-1 Audio Layer-). 3) According to the standard, the data is compressed and an audio data file is created and sent to the memory card 32 or the built-in memory 33, while the audio data file sent from the memory card 32 or the built-in memory 33 is uncompressed at the time of playing the sound. Then, it is converted into an analog signal and the speaker unit (SP) 43 is driven to emit loud sounds.

  Furthermore, the sound processing unit 40 generates various operation sounds, for example, a pseudo shutter sound associated with the operation of the shutter key, a beep sound associated with the operation of other keys, and the like based on the control from the control unit 25. The sound is emitted from 43.

  The strobe drive unit 41 charges a large-capacitance capacitor for strobe (not shown) at the time of still image shooting, and then drives the strobe light emitting unit 45 to flash based on the control from the control unit 25.

(First embodiment)
Next, power remaining amount determination processing in the camera device 1 of the first embodiment will be described with reference to the flowchart shown in FIG. Here, it is assumed that an alkaline battery or a high-voltage holding battery is arbitrarily attached and used as the battery 35 by the user.

  FIGS. 3A and 3B are diagrams illustrating voltage value change characteristics depending on the type of battery 35 used in the camera apparatus 1, and a series of shooting operations including, for example, zoom drive, focus drive, and shutter drive. Shows an example in which is repeatedly executed, for example, every 10 seconds. FIG. 3A is a diagram showing a voltage change of the alkaline battery, and FIG. 3B is a diagram showing a voltage change of the high voltage holding battery. As shown in FIG. 3, by supplying current to each unit in order to execute each photographing operation, a drop in voltage value occurs in accordance with the execution of each photographing operation. FIG. 4 is a diagram showing the characteristics of a general discharge curve of an alkaline battery or the like and the characteristics of a discharge curve of a high voltage holding battery in an easily understandable state near the end of the battery.

  As shown in FIG. 3A, in the alkaline battery, the voltage drop value (drop width) of the voltage value when the photographing operation is executed (current supply) from when the voltage value is high until the voltage value becomes low. ) Gradually increases. On the other hand, as shown in FIG. 3B, in the high voltage holding battery, when the voltage value is high, the voltage value drop value when the photographing operation is executed (current supply) is small, but the voltage The voltage drop value suddenly increases as the value decreases (see the range indicated by the broken line in FIG. 3).

  FIG. 5 is an enlarged view of the range indicated by the broken line shown in FIG. As shown in FIG. 5, by supplying current to each part (load) in order to execute a photographing operation, a drop in voltage value occurs in accordance with the driving of each part, and in particular, shutter driving indicated by a circle in the figure. The biggest decline has occurred. In the case of a high voltage holding battery, when the photographing operation is not executed (no load), even if the battery is in a high voltage state, as shown in FIG. In addition, the voltage value at no load also drops. FIG. 6 is a diagram showing a comparison of drop amounts when an alkaline battery and a high voltage holding battery are loaded.

  Therefore, the end of the high-voltage holding battery is determined based on the drop amount at the time of loading such as shutter driving for each battery, for example, the drop (drop amount) at the time of loading of the high-voltage holding battery shown in FIG. A reference value for the voltage drop value that can be set is set.

  In the first embodiment, the control unit 25 (CPU) of the camera device 1 in a normal operation state at regular intervals (for example, 1 second) so that the remaining amount determination process does not affect other operations. The remaining battery level determination process is executed.

  When the control unit 25 determines that a predetermined time has elapsed from the previously executed battery remaining amount determination process (step A0, Yes), the operation ends when another operation is being performed (step A1, Yes). The voltage measurement of the battery 35 is executed after waiting for (Step A1, No).

  The control unit 25 acquires data indicating the voltage value of the battery from the A / D conversion unit, and records this as a detection voltage at no load (step A2). Here, the control unit 25 compares the recorded no-load voltage value with a reference voltage value set for determining the end stage of an alkaline battery or the like other than the high voltage holding battery, and performs the end stage determination. (Step A3). As a result, when the detected voltage value is equal to or lower than the reference voltage value (step A3, Yes), the battery 35 being used is other than a high voltage holding battery such as an alkaline battery and is in an end state. judge.

  In this case, the control unit 25 causes the display unit 29 to display a notification for a decrease in the remaining battery level through the VRAM controller 26 or outputs a predetermined warning sound from the speaker unit 43 through the audio processing unit 40. Then, the user is notified of a decrease in the remaining battery level (step A9).

  Further, all the operations currently being processed are completed (step A10), and after the taking lens 11 is housed and completed normally (step A11), the power supply to each unit is stopped (off) (step). A12).

  On the other hand, when the voltage value at the time of no load is not less than or equal to the reference voltage value, the control unit 25 causes the power supply control unit 34 to start supplying current to the specific load (step A4). Here, it may be a current supply to a component for realizing a function executed in accordance with a user operation, or may be a dummy load mounted for determining the remaining amount of power.

  Here, the control part 25 measures the battery voltage which changed by supplying power to the load, and records it as a detection voltage at the time of the load (step A5). And the control part 25 stops the electric current supply with respect to a specific load (step A6).

  Here, the control unit 25 detects the difference between the detected voltage at the time of no load and the load that has been recorded previously (step A7), and the voltage difference is equal to or greater than a predetermined value (reference value) determined in advance. (Step A8).

  Here, when the difference between the detection voltage at the time of no load and the load is not equal to or greater than a predetermined value, the control unit 25 determines that the remaining amount of the battery 35 is sufficient (No in Step A8).

  On the other hand, when the difference between the detection voltage at the time of no load and the load is equal to or greater than a predetermined value (step A8, Yes), the control unit 25 determines that the remaining amount of the battery 35 is low and is in an end state. To do. That is, even when the voltage value of the battery 35 at no load is high, as shown in the characteristics shown in FIG. The terminal state is determined.

  The control unit 25 displays to the user through the VRAM controller 26 to notify the display unit 29 of the decrease in the remaining battery level, or outputs a predetermined warning sound from the speaker unit 43 through the audio processing unit 40. In contrast, a decrease in the remaining battery level is notified (step A9).

  Then, all the operations currently being processed are completed (step A10), and after the taking lens 11 is housed and completed normally (step A11), the power supply to each unit is stopped (off) (step) A12).

  Thus, in the first embodiment, since the determination of the remaining battery level is performed based on the difference between the battery voltage at no load and the battery voltage at no load, even if the battery voltage is high, Even when a battery with the characteristic that the voltage value drops greatly during operation near the end of the period is used, it is determined that the remaining battery level is low so that the remaining battery level is sufficient to complete the operation in the middle of processing. Thus, the current operation state can be terminated normally.

(Second Embodiment)
Next, power remaining amount determination processing in the camera device 1 of the second embodiment will be described with reference to the flowchart shown in FIG.
In the second embodiment, using the fact that the voltage drop value of the battery 35 is the largest when the shutter is driven in a series of shooting operations of the camera device 1, the voltage value of the battery 35 before and after the shutter drive and the voltage value during the shutter drive are Based on the difference, the remaining amount determination of the battery 35 is executed.

  FIG. 8 is a diagram illustrating a voltage change accompanying a photographing operation of the camera device 1 when the high voltage holding battery illustrated in FIG. 5 is used. FIG. 8 shows voltage changes when a series of photographing operations including, for example, zoom driving, focus driving, and shutter driving are repeatedly performed at 10-second intervals, and shows that the voltage drop during shutter driving is the largest. Yes. Note that the time during which the voltage drops due to the shutter drive in FIG. 8 is shown in an easily understandable manner (actually, the time during which the voltage drops with the shutter drive is about 20 ms). In FIG. 8, the measurement timing of the battery voltage is indicated by a vertical line in the graph (at regular time intervals (for example, every 1 second) during normal operation).

  First, when the control unit 25 detects a pressing operation on the shutter button of the key input unit 37 (step B0, Yes), the data (voltage) indicating the voltage value of the battery 35 from the A / D conversion unit immediately before starting the shutter drive. The value A) is acquired and recorded (step B1). That is, the voltage value of the battery 35 immediately before the voltage drop is detected by supplying current to each part (specific load) for driving the shutter separately from the detection at regular time intervals at the timing A in FIG. .

  Here, the control unit 25 compares the recorded voltage value immediately before driving the shutter (no load) and a reference voltage value set to determine the end of the alkaline battery other than the high voltage holding battery. Then, the end stage determination is performed (step B3). As a result, when the detected voltage value is equal to or lower than the reference voltage value (step B3, Yes), the used battery 35 is other than a high voltage holding battery such as an alkaline battery and is in an end state. judge.

  In this case, the control unit 25 causes the display unit 29 to display a notification for a decrease in the remaining battery level through the VRAM controller 26 or outputs a predetermined warning sound from the speaker unit 43 through the audio processing unit 40. Then, the user is notified of a decrease in the remaining battery level (step B11).

  Further, after all the operations currently being processed are completed (step B12) and the photographing lens 11 is housed and completed normally (step B13), the power supply to each unit is stopped (turned off) (step B13). B14).

  On the other hand, if the voltage value immediately before the shutter drive is not less than or equal to the reference voltage value, the control unit 25 starts the shutter drive, and supplies power to each unit for performing the shutter drive by the power supply control unit 34. To do. Thereby, the voltage value of the battery 35 falls as shown in FIG.

  Here, the control unit 25 acquires and records data (voltage value B) indicating the voltage value of the battery 35 from the A / D conversion unit (step B4). That is, the voltage value of the battery 35 is detected while the voltage drop occurs at the timing B in FIG.

  Further, after waiting for a predetermined time in a range where the shutter drive is not completed (step B5), similarly, the voltage value (voltage value C) of the battery 35 while the voltage drop occurs at the timing C in FIG. Is measured and recorded (step B6).

  Thereafter, the control unit 25 stops the shutter drive (step B7), and stops the supply of current to each unit for executing the shutter drive by the power supply control unit 34. As a result, the voltage value of the battery 35 returns to the voltage value before the shutter driving as shown in FIG. Here, immediately after the shutter drive is completed, the control unit 25 acquires and records data (voltage value D) indicating the voltage value of the battery 35 from the A / D conversion unit (step B8).

  Then, the control unit 25 uses the voltage values A and D measured before and after the shutter drive and the voltage values B and C measured during the shutter drive to determine the voltage value when the shutter is not driven. The difference from the voltage value when the shutter is driven is calculated (step B9). That is, the average value of the voltage values A and D measured before and after the shutter drive and the voltage value measured between the shutter drives by (voltage value A + voltage value D) / 2− (voltage value B + voltage value C) / 2. The difference from the average value of B and C is calculated.

  Here, the control unit 25 determines whether or not the difference between the average value of the voltage values before and after shutter driving and the average value of the voltage values during shutter driving is equal to or greater than a predetermined value (step B10). .

  Here, when the difference between the average values is not equal to or greater than the predetermined value, the control unit 25 determines that the remaining amount of the battery 35 is sufficient (No in Step B10).

  On the other hand, when the difference between the average values is equal to or greater than the predetermined value (step B10, No), the control unit 25 determines that the remaining amount of the battery 35 is low and is in an end state. That is, even if the voltage value before and after the shutter driving of the battery 35 is in a high state, as shown in the characteristics shown in FIG. The terminal state is determined.

  The control unit 25 displays to the user through the VRAM controller 26 to notify the display unit 29 of the decrease in the remaining battery level, or outputs a predetermined warning sound from the speaker unit 43 through the audio processing unit 40. In contrast, a decrease in the remaining battery level is notified (step B11).

  Then, all the operations currently being processed are completed (step B12), and after the taking lens 11 is housed and completed normally (step B13), the power supply to each unit is stopped (turned off) (step B13). B14).

  As described above, in the second embodiment, the voltage value of the battery 35 is measured before and after the shutter driving and during the shutter driving to target the voltage drop due to the shutter driving where the voltage drop of the battery 35 is large. Since the amount determination is executed, there is no need to always measure the voltage of the battery 35 (for example, at an interval shorter than 1 second), and there is no possibility that the processing load due to the battery remaining amount determination is increased. In addition, since the determination is performed using the average value obtained by measuring the voltage a plurality of times, it is possible to reduce the influence of the fluctuation of the voltage value that appears instantaneously and the like, and it is possible to determine the remaining battery level stably.

  In addition, although the difference of the voltage value using the average value of 2 times measured before and after shutter driving and the average value of 2 times at the time of shutter driving is calculated, the voltage value of the battery 35 is measured 3 times or more. Thus, the average value may be calculated. In addition, the number of times measured before and after shutter driving may not be the same as the number of times measured during shutter driving.

  Furthermore, in the above description, the remaining amount of the battery 35 is determined based on the difference between the voltage value before and after driving and the voltage value during driving for the time of shutter driving, but for other specific loads. It may be executed for a driving operation accompanied by a voltage drop by supplying current.

  Further, since the voltage value is measured at the time of loading such as when the shutter is driven, the number of times of voltage value measurement at a normal constant time (for example, 1 second) may be reduced to further reduce the burden. .

(Third embodiment)
In the third embodiment, the remaining battery level determination process is executed using a reference value corresponding to the type of the battery 35, thereby making it possible to more accurately determine the remaining battery level (late stage) regardless of the difference in the battery type. .

  FIG. 9 shows an example of data registered in the determination condition table 25 a prepared in advance in the control unit 25.

  In the determination condition table 25a, for each battery type, voltage determination conditions (voltage values) during steady operation and a voltage drop determination for a voltage that drops by supplying a current to a specific load (for example, a component related to shutter driving). An AND / OR condition is set that indicates whether the determination is based on both the condition (voltage value width) and whether the determination is based on both the voltage determination condition and the voltage drop determination condition (AND condition) or one (OR condition). ing.

  For example, in FIG. 9, the respective data are registered for alkaline batteries, nickel batteries, high voltage holding batteries, and the like. Further, default data when the battery type is not specified is registered. As data for alkaline batteries, data indicating 2.0 V or less as a voltage determination condition, 0.4 V or more as a voltage drop determination condition, and data indicating an AND condition as an AND / OR condition are registered. As data for the default, data of 2.0 V or less as a voltage determination condition, 0.6 V or more as a voltage drop determination condition, and OR condition data as an AND / OR condition are registered.

  First, a process for setting which of the data indicating the reference value registered in the determination condition table 25a is used will be described. In the third embodiment, the battery is set by a battery type setting process for the user to set the type of the battery 35 attached to the camera device 1 or a battery type determination process for automatically determining the battery type attached to the camera device 1. 35 types are specified, and the remaining battery level determination process is executed using data registered in the determination condition table 25a corresponding to the types. Only one of the processes may be executed in advance, or may be executed by the user arbitrarily selecting either one in mode setting or the like.

  First, the battery type setting process will be described with reference to the flowchart shown in FIG.

  First, when a battery type setting request is input by a predetermined key operation of the key input unit 37 by the user, the control unit 25 selects a battery type prepared according to the battery type registered in the determination condition table 25a. The menu is displayed on the display unit 29 through the VRAM controller 26 (step C1). For example, in the battery type selection menu, corresponding selection items such as an alkaline battery, a nickel battery, and a high voltage holding battery are prepared.

  Here, the user can arbitrarily designate one of the selection items of the battery type selection menu as a selection candidate by operating the cross key (cursor key) of the key input unit 37, and can select and confirm the selection by operating the selection key. it can.

  When any selection item (battery type) is selected from the battery type selection menu (step C2, Yes), the control unit 25 records type information indicating the selected battery type (step C3). . Thereby, in the battery remaining charge determination process mentioned later, the process using the data according to the kind information registered into the determination condition table 25a can be performed.

  Next, the battery type determination process will be described with reference to the flowchart shown in FIG. The battery type determination process is executed when the battery 35 is attached to the camera device 1. First, the control unit 25 acquires and records a voltage value in an initial state immediately after the battery 35 is mounted through the A / D conversion unit 36 (step D1).

  Thereafter, the control unit 25 determines whether a predetermined time has elapsed since the battery 35 was mounted while performing a normal operation (step D2).

  For example, in the camera apparatus 1, in the normal shooting mode, the display unit 29 displays an image (through image) based on the image information captured from the VRAM controller 26 at that time as a monitor display unit (electronic finder) in real time. it's shown. By executing such a normal operation for about 5 to 10 minutes, the battery 35 is consumed, and the voltage drops according to the discharge curve corresponding to the battery type.

  When it is determined that a predetermined time (for example, 10 minutes) has elapsed, the control unit 25 acquires the voltage value of the battery 35 at that time through the A / D conversion unit 36 (post-elapsed voltage value), and the post-elapsed voltage. The battery type is determined based on the difference between the value and the previously recorded initial voltage value (step D4).

  For example, as shown in FIG. 3 or FIG. 4, since the discharge curve is different between an alkaline battery or the like and a high voltage holding battery, after a predetermined time elapses while the battery 35 is mounted and performing normal operation, That is, the voltage is stepped down to a voltage according to the discharge curve corresponding to the type of battery. For example, the alkaline battery has a larger voltage drop value than the high voltage holding battery. Therefore, it is possible to determine the type of the attached battery 35 based on the difference between the post-elapsed voltage value and the initial voltage value.

  When a through image is displayed in the shooting mode, for example, the voltage value is detected after elapse of 10 minutes. However, when another operation mode is being executed (for example, the playback mode). In this case, the passage of time according to the operation mode may be monitored.

  If the battery type cannot be determined from the difference from the voltage value after the lapse of a predetermined time (step D5, No), the side and the voltage value after the lapse are measured after the predetermined time has elapsed. Similarly, the difference from the initial voltage value is obtained to determine the battery type (steps D2 to D4). However, when measuring the voltage value after the second time or later, the elapsed time may be shortened.

  When the battery type is determined from the change in the voltage value of the battery 35 (step D5, Yes), the control unit 25 records type information indicating the determined battery type (step D6). Thereby, in the battery remaining charge determination process mentioned later, the process using the data according to the kind information registered into the determination condition table 25a can be performed.

  Next, the remaining battery level determination process in the third embodiment will be described with reference to the flowchart shown in FIG.

  First, the control unit 25 determines whether type information about the battery 35 being used is set (step E1).

  Here, when the type information is not set (step E1, No), the control unit 25 adopts the determination condition for the default registered in the determination condition table 25a, and the voltage acquired from the determination condition table 25a. The determination condition, voltage drop determination condition, and AND / OR condition data are temporarily stored for use in subsequent processing (step E2).

  On the other hand, when the type information is set (step E1, Yes), the control unit 25 adopts the determination condition for the corresponding battery type registered in the determination condition table 25a, and similarly, the determination condition table 25a. Are temporarily stored (step E3).

  Here, the control part 25 acquires the voltage value at the time of the steady state which is not supplying the electric current with respect to a specific load through the A / D conversion part 36 (step E4). The control unit 25 determines whether the voltage value in the steady state and the voltage value set in the voltage determination condition are satisfied (step E5). For example, when default determination conditions are employed, it is determined whether the steady-state voltage is 2.0 V or less.

  As a result, when it is determined that the voltage determination condition is not satisfied (step E5, No), the control unit 25, when the AND condition is registered as the AND / OR condition (step E6, Yes), It is determined that the remaining amount of the battery 35 is present (not at the end) (step E10).

  When the AND condition is not registered as the AND / OR condition (No at Step E6), the control unit 25 measures the voltage drop value at the time of shutter driving as the specific load (Step E8). That is, through the A / D conversion unit 36, the voltage value at the time of shutter driving is obtained a plurality of times (twice), the average is obtained through the same as in the second embodiment, and the difference from the voltage value previously measured in the steady state Is calculated as a voltage drop value.

  The control unit 25 determines whether the voltage drop value satisfies the voltage condition set in the voltage drop determination condition (step E9). For example, when the default determination condition is adopted, it is determined whether the voltage drop value is 0.6 or more.

  Here, when the voltage drop determination condition is not satisfied (step E9, No), the control unit 25 determines that the remaining amount of the battery 35 is present (not at the end) (step E10). On the other hand, when the voltage drop determination condition is satisfied (step E9, Yes), the control unit 25 determines that the remaining amount of the battery 35 is not present (terminal stage) (step E11).

  On the other hand, when it is determined in step E5 that the voltage determination condition is satisfied (step E5, Yes), the control unit 25 determines that the OR condition is registered as the AND / OR condition (step E7, Yes). ), It is determined that the remaining amount of the battery 35 is not present (terminal stage) (step E11).

  When the OR condition is not registered as the AND / OR condition (No at Step E7), the control unit 25 measures the voltage drop value at the time of driving the shutter as the specific load in the same manner as described above (Step S7). E8).

  The control unit 25 determines whether the voltage drop value satisfies the voltage condition set in the voltage drop determination condition (step E9).

  Here, when the voltage drop determination condition is not satisfied (No at Step E9), the control unit 25 determines that the remaining amount of the battery 35 is present (not at the end) (Step E10), and sets the voltage drop determination condition. When it is satisfied (step E9, Yes), it is determined that the remaining amount of the battery 35 is not present (terminal stage) (step E11).

  In this way, in the third embodiment, since the remaining amount determination is performed using the determination condition registered in the determination condition table 25a, an appropriate end-stage determination according to the battery type of the actually installed battery 35 is performed. Can be executed. In addition, by setting the AND / OR condition, not only the determination based on the voltage determination condition but also the difference between the voltage value during the steady state and the voltage value during the load (as in the first and second embodiments) It can be determined based on the voltage drop value. Therefore, depending on the characteristics of the battery type, for example, a battery having sufficient voltage characteristics only by determination using voltage determination conditions, or a battery having characteristics that require determination based on voltage drop determination conditions as well as voltage determination conditions , Determination suitable for each can be executed.

  In each of the above-described embodiments, the remaining amount of the battery 35 is determined by comparing the difference between the voltage value at the steady state and the voltage value at the time of loading with a preset reference value. The reference value may be dynamically changed according to the current operation state so that the amount of electric power necessary for normally ending the operation of the camera apparatus 1 can be left. For example, in a state where the photographing lens 11 is extended to the zoom position in the photographing mode, a reference value that retains electric power for normally housing the photographing lens 11 is used, and the motor 10 is driven in the reproduction mode. If unnecessary, a lower reference value may be used.

  In the above-described embodiment, the camera apparatus 1 has been described. However, the present invention can be applied to other devices driven by a battery, such as a mobile phone or a personal digital assistant (PDA). For example, in the case of a cellular phone, the remaining voltage of the battery 35 is determined in the same manner as in the first to third embodiments by measuring the voltage value at the time of transmission or reception as the voltage value at the time of load. Can be executed.

  Further, in each of the above-described embodiments, it is assumed that the end-of-stage determination can be made appropriately for a high-voltage holding battery having a characteristic that the voltage drops rapidly near the end, but a battery manufactured with other poor quality, that is, a stable battery Thus, it is possible to appropriately determine the end of the battery even if the battery has a characteristic (discharge curve) in which the voltage value suddenly drops without maintaining the voltage value.

  Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, at least one of the problems described in the column of problems to be solved by the invention can be solved, and described in the column of the effect of the invention. In a case where at least one of the obtained effects can be obtained, a configuration in which this configuration requirement is deleted can be extracted as an invention.

  Further, a battery remaining amount determination processing program that can be executed by a computer mounted on the camera apparatus 1 is recorded on, for example, a magnetic disk (flexible disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), a semiconductor memory, etc. It can be written on a medium or provided through a communication medium. By controlling the operation of the computer mounted on the camera device 1 by the battery remaining amount determination processing program, the battery remaining amount monitoring function in the above-described embodiment can be realized.

The block diagram which shows the structure of the camera apparatus 1 which implement | achieves the battery remaining charge determination apparatus in embodiment of this invention. The flowchart for demonstrating the power supply residual amount determination process in the camera apparatus 1 of 1st Embodiment. The figure which shows the change characteristic of the voltage value by the difference in the kind of battery 35 used with the camera apparatus 1. FIG. The figure which shows the state of the general discharge curve of an alkaline battery etc., and the state of the discharge curve of a high voltage holding battery near the end of the battery. The figure which expands the range shown with the broken line shown in FIG.3 (b), and is shown clearly. The figure which compares and shows the drop amount at the time of load of an alkaline battery and a high voltage holding battery. The flowchart for demonstrating the power supply residual amount determination processing in the camera apparatus 1 of 2nd Embodiment. The figure for demonstrating the operation | movement of the voltage value measurement in 2nd Embodiment. The figure which shows an example of the data registered into the determination condition table 25a prepared beforehand by the control part 25 in 3rd Embodiment. The flowchart for demonstrating operation | movement of the battery type setting process and battery type discrimination | determination process in 3rd Embodiment. The flowchart for demonstrating the battery remaining charge determination process in 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Camera apparatus, 11 ... Shooting lens, 10 ... Motor (M), 12 ... CCD, 13 ... Timing generator (TG), 14 ... Vertical driver, 15 ... Sample hold circuit (S / H), 16 ... A / D converter, 17 ... color process circuit, 18 ... DMA controller, 20 ... DRAM interface (I / F), 21 ... DRAM, 25 ... control unit, 26 ... VRAM controller, 27 ... VRAM, 28 ... digital video encoder, 29 DESCRIPTION OF SYMBOLS ... Display part, 30 ... Image processing part, 32 ... Memory card, 33 ... Built-in memory, 34 ... Power supply control part, 35 ... Battery, 36 ... A / D conversion part, 37 ... Key input part, 40 ... Sound processing part, 41 ... Strobe drive unit, 42 ... Microphone unit (MIC), 43 ... Speaker unit (SP), 45 ... Strobe light emitting unit.

Claims (9)

In the battery remaining amount determination device for determining the remaining amount of the battery,
First detection means for detecting a voltage value of the battery when no current is supplied to the specific load;
A second detecting means for detecting a voltage value of the battery when supplying a current to the specific load;
Calculating means for calculating a difference between the first voltage value detected by the first detecting means and the second voltage value detected by the second detecting means;
A battery remaining capacity determining apparatus comprising: a determining means for determining the remaining battery capacity based on a voltage value calculated by the calculating means and a preset reference value. Comprising a determination means for determining an instruction to start current supply to the specific load;
2. The remaining battery level determining apparatus according to claim 1, wherein the first detecting unit detects a voltage value immediately before the current supply to the specific load is started in accordance with the determination by the determining unit. The first detection means detects a voltage value before and after supplying current to the specific load,
The second detection means detects a voltage value a plurality of times when supplying current to the specific load,
2. The battery according to claim 1, wherein the calculating means calculates a difference between an average of the voltage values detected by the first detecting means and an average of the voltage values detected by the second detecting means. Remaining amount determination device. Determination condition recording means for recording a reference value based on the determination by the determination means for each of a plurality of battery types;
The remaining battery level according to claim 1, wherein the determination unit determines a remaining battery level based on a reference value recorded by the determination condition recording unit and corresponding to a battery to be determined. Judgment device. Provided with type information input means for inputting type information indicating the type of battery,
5. The battery determination unit according to claim 4, wherein the determination unit determines a remaining battery level based on a reference value recorded by the determination condition recording unit corresponding to the type information input by the type information input unit. The battery remaining charge determination apparatus of description. Initial voltage value detecting means for detecting an initial voltage value of the battery;
A post-elapsed voltage value detecting unit for measuring a voltage value after a predetermined time has elapsed since the voltage value was detected by the voltage value detecting unit;
Battery type determining means for determining the battery type based on the difference between the voltage value detected by the initial voltage value detecting means and the voltage value detected by the post-elapsed voltage value detecting means;
5. The determination unit according to claim 4, wherein the determination unit determines a remaining battery level based on a reference value recorded by the determination condition recording unit corresponding to the type determined by the battery type determination unit. Battery remaining capacity judgment device.   2. The remaining battery level determining apparatus according to claim 1, wherein the determining unit determines the remaining battery level based on a reference value for determining a currently required remaining battery level. In digital cameras powered by batteries,
First detecting means for detecting a voltage value of the battery when the shutter is not driven;
Second detection means for detecting a voltage value of the battery when the shutter is driven;
Calculating means for calculating a difference between the first voltage value detected by the first detecting means and the second voltage value detected by the second detecting means;
A digital camera comprising: a determination unit that determines a remaining amount of the battery based on a voltage value calculated by the calculation unit and a preset reference value. A battery remaining capacity determination method for determining a remaining battery capacity,
A first detection step of detecting a voltage value of the battery when no current is supplied to the specific load;
A second detection step of detecting a voltage value of the battery when current is supplied to the specific load;
A calculation step for calculating a difference between the first voltage value detected by the first detection step and the second voltage value detected by the second detection step;
A battery remaining capacity determining method comprising: a determining step for determining the remaining battery capacity based on the voltage value calculated in the calculating step and a preset reference value.

Images