JP2018207739A - Imaging apparatus - Google Patents

Abstract

To enable capacity learning without operation of a battery pack protection function, when performing the capacity learning in an imaging apparatus.SOLUTION: An imaging apparatus (123) is connectable to a battery pack which includes: a secondary battery; current detection means which detects a charge/discharge current of the secondary battery; storage means which stores a learning capacity corresponding to a dischargeable capacity of the secondary battery from a full charge state to a discharge completion state; and update means which updates the learning capacity when the secondary battery becomes the discharge completion state. After reaching the operation prohibition state of a first operation mode of the imaging apparatus, the imaging apparatus permits an operation mode, in which a current amount flowing through the secondary battery and a current change amount are smaller than predetermined values, so as to shift to a second operation mode in which operation can be performed to the discharge completion state of the secondary battery.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an imaging apparatus to which a battery pack can be connected and a control method therefor.

  Conventionally, it is known that a battery pack used in an imaging device includes a battery pack that can update a dischargeable capacity (learning capacity) of a secondary battery from a fully charged state to a discharge end state.

  Since the learning capacity changes depending on the use condition of the battery pack and the aging of the secondary battery in the battery pack, a gradual difference occurs between the learning capacity and the actual capacity. In order to correct the discrepancy between the learning capacity and the actual capacity, it is necessary to appropriately update the learning capacity (capacity learning).

  Patent Document 1 describes a method of storing a discharge capacity from a fully charged state to a discharge end state and updating the discharge capacity as a learning capacity when the battery pack is in a discharge end state. Yes.

  Patent Document 2 describes a method of performing capacity learning by correcting the learning capacity according to the number of times the battery pack is charged when the battery pack reaches a predetermined voltage.

JP 2009-162623 A JP 2004-14228 A

  However, the methods described in Patent Documents 1 and 2 have a problem when performing battery pack capacity learning in the imaging apparatus. Specifically, the imaging device has a large current and large current fluctuation operation mode such as high-speed continuous shooting, and when there is a certain deviation between the learning capacity and the actual capacity, There is a concern that the secondary battery will be below the discharge end voltage.

  The battery cell protection function of the secondary battery in the battery pack has a function to shut off the discharge circuit in the battery pack so that the secondary battery will not be overdischarged when the voltage becomes lower than the discharge end voltage. May have. In this case, when the protection function is activated, the terminal supplying power to the connection portion from the battery pack to the imaging device is released, and thus the operation is suddenly stopped while the imaging device is in use.

  Therefore, an object of the present invention is to enable capacity learning without performing a battery pack protection function when capacity learning is performed in an imaging apparatus.

In order to achieve the above object, an imaging apparatus according to the present invention includes:
A secondary battery; current detection means for detecting a charge / discharge current of the secondary battery; and storage means for storing a learning capacity corresponding to a dischargeable capacity of the secondary battery from a fully charged state to a discharge end state. An imaging device connectable to a battery pack having an updating means for updating the learning capacity when the secondary battery is in a discharge end state, and prohibiting operation in the first operation mode of the imaging device After reaching the state, permitting an operation mode in which the amount of current flowing through the secondary battery and the amount of current fluctuation are smaller than predetermined, and shifting to the second operation mode in which the secondary battery can operate until the discharge end state. It is characterized by.

  According to the imaging apparatus according to the present invention, when capacity learning is performed in the imaging apparatus, capacity learning can be performed without the protection function of the battery pack being operated.

6 is a block diagram for explaining an example of configurations of an imaging device 123 and a battery pack 105 in Embodiments 1, 2, and 3. FIG. 3 is a flowchart for explaining a flow of battery check and capacity learning of a battery pack 105 in the first embodiment. It is a figure which shows the example of the information for notifying a user that the imaging device 123 reached | attained the operation prohibition state. 6 is a flowchart for explaining a flow of battery check and capacity learning of the battery pack 105 in the second embodiment. It is a figure which shows the example of the information for making a user select whether the capacity learning of the battery pack 105 is performed. It is a figure which shows the example of the information for notifying a user that it is during capacity learning. 14 is a flowchart for explaining a flow of battery check and capacity learning of the battery pack 105 in the third embodiment. It is a figure which shows the example of the information for notifying a user of the function etc. which can be performed with the imaging device 123 during capacity learning.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments.

[Embodiment 1]
FIG. 1 is a block diagram for explaining an example of the configuration of the imaging device 123 and the battery pack 105 in the first, second, and third embodiments.

  In the first, second, and third embodiments, the battery pack 105 can be connected to the imaging device 123.

  First, an example of the configuration of the battery pack 105 will be described with reference to FIG.

  The battery pack 105 includes a secondary battery 101, a current detection unit 102, a memory 103, a battery pack control unit 104, a voltage conversion unit 106, a voltage detection unit 107, a protection circuit 108, a + terminal 109, a D terminal (communication terminal) 110, -It has the terminal 111 and the temperature detection part 112.

  The secondary battery 101 has, for example, two battery cells connected in series. The secondary battery 101 is, for example, a lithium ion battery. One terminal of the secondary battery 101 is connected to the + terminal 109 via the protection circuit 108 and also connected to the voltage conversion unit 106. The other terminal of the secondary battery 101 is connected to the negative terminal 111 via the current detection unit 102 for measuring the charging or discharging current of the secondary battery 101 and also connected to the GND in the battery. Yes.

  The current detection unit 102 is a low resistor such as 20 mΩ, for example, and converts the charge / discharge current into a voltage, and the battery pack control unit 104 performs A / D conversion to measure the charge / discharge current.

  The memory 103 is a rewritable nonvolatile memory, for example, and stores a program for controlling each component of the battery pack 105. Further, the memory 103 corresponds to a capacity of the secondary battery 101 in a fully charged state (corresponding to a learning capacity), an integrated value of charging / discharging current, and a remaining capacity (a capacity obtained by subtracting the integrated value of charging / discharging current from the learning capacity). ) Is remembered.

  The battery pack control unit 104 is composed of, for example, a one-chip microcomputer having AD conversion, ROM / RAM, and a timer, and controls the operation of each component of the battery pack 105. The battery pack control unit 104 reads a program for operating the battery pack 104 stored in the ROM in the battery pack control unit 104, develops it in the RAM in the battery control microcomputer 104, and controls the operation of each component. To do.

  In addition, the battery pack control unit 104 integrates the charge / discharge current measured by the current detection unit 102 at regular intervals (for example, 100 ms cycle), and causes the memory 103 to store the integrated value of the charge / discharge current. As described above, the battery pack control unit 104 stores the capacity obtained by subtracting the accumulated value of the charge / discharge current from the learned capacity in the memory 104 as the remaining capacity.

  The voltage conversion unit 106 includes, for example, a linear regulator, and supplies a constant voltage (for example, 3 V) to the battery pack control unit 104. As a result, the battery pack control unit 104 can operate even when the battery pack 105 is detached from the imaging device 123.

  The voltage detection unit 107 includes, for example, an A / D converter, detects the voltage of each battery cell of the secondary battery 101, and transmits it to the battery pack control unit 104.

  The protection circuit 108 includes a charge protection FET and a discharge protection FET, and is a switch that shuts off the circuit so as not to be overcharged or discharged during charging and discharging, and is controlled by the battery pack control unit 104. . For example, when one of the voltages of each battery cell detected by the voltage detection unit 107 is 2.4 V or less, the battery pack control unit 104 determines that the secondary battery 101 is in an overdischarge state, The discharge protection FET in the protection circuit 108 is controlled to be cut off.

  The temperature detection unit 112 is configured by, for example, a thermistor, converts a temperature change into a resistance value, and AD converts it at an A / D port of the battery pack control unit 104 to detect the temperature of the battery pack 105.

  When the battery pack 105 is connected to the imaging device 123, a voltage is supplied between the + terminal 109 and the − terminal 111, and power is supplied to the imaging device 123. In addition, the imaging device 123 and the D terminal 110 of the battery pack 105 are connected, and the battery pack control unit 104 and the control unit 114 can communicate with each other.

  Next, an example of the configuration of the imaging device 123 will be described with reference to FIG.

  Similarly to the battery pack 105, the imaging device 123 has a + terminal connected to the + terminal 109, a D terminal (communication terminal) connected to the D terminal 110, and a − terminal connected to the − terminal 111.

  The voltage conversion unit 113 includes, for example, a switching regulator or a linear regulator, and supplies a predetermined voltage to each component in the imaging device 123 as well as the control unit 114.

  The control unit 114 is composed of, for example, a one-chip microcomputer having AD conversion, ROM / RAM, a timer, and the like, and controls the operation of each component of the imaging device 123. The control unit 114 reads, for example, a program for operating each component of the imaging device 123 stored in the ROM in the control unit 114, expands the program in the RAM in the control unit 114, and performs the operation of each component. Control.

  Further, the control unit 114 determines a shutter speed and an aperture value according to the exposure amount calculated by an exposure calculation unit (not shown), and transmits it to a lens driving unit 117 and a shutter control unit 116 described later.

  The image processing unit 115 applies A / D conversion processing to the analog image signal input from the image sensor 120 to convert it into digital image data. Thereafter, the image processing unit 115 applies various image processing such as resolution conversion processing and color tone conversion processing to the digital image data, and records the digital image data in a recording medium 124 described later.

  The shutter drive unit 116 drives the shutter 121 according to the shutter speed information determined by the control unit 114.

  The lens driving unit 117 drives the focusing lens (focus lens) of the lens unit 122 according to information on the position of the focusing lens that focuses on the subject detected by the focus detection unit (not shown). The lens driving unit 117 receives the exposure amount information determined by the control unit 114 and drives the aperture of the lens unit 122 according to the aperture value information determined by the control unit 114.

  The display unit 118 is a display device having a liquid crystal display. The display unit 118 can sequentially display (through display) the subject image output from the image sensor 120. The display unit 118 not only functions as an electronic viewfinder by through display, but also displays, for example, a GUI for setting the imaging device 123 and an image recorded on a recording medium. Note that the imaging device 123 also has a display device on the right shoulder of the imaging device 123.

  The operation unit 119 has a user input interface included in the imaging device 123 such as a power button and a release button, for example, receives an operation from the user for each button, and notifies the control unit 114 that there is an input. The operation unit 119 receives a process corresponding to an operation by each switch provided to the lens connected to the imaging device 123 and notifies the control unit 114 that there is an input.

  The image pickup device 120 is, for example, a CCD or CMOS sensor, and photoelectrically converts a subject image that is incident on the image pickup device 123 via the lens unit 122 and forms an analog image signal to the image processing unit 115. Output.

  The lens unit 122 includes, for example, a lens group such as a focusing lens (focus lens) and a zoom lens, an aperture, a shutter, and the like, and takes in reflected light from a subject into the imaging device 123.

  The recording medium 124 is a detachable recording medium used by being connected to the imaging device 123 such as a recording storage area built into the imaging device 123, a memory card, an HDD, or the like.

  Next, the flow of battery check and capacity learning of the battery pack 105 in the first embodiment will be described with reference to the flowchart of FIG.

  The processing described with reference to the flowchart of FIG. 2 is started at regular intervals (for example, every 5 seconds) after the battery pack 105 is inserted into the imaging device 123 and the imaging device 123 is turned on.

  In step S <b> 201, the control unit 114 communicates with the battery pack control unit 104 to acquire remaining amount information of the battery pack 105. The battery pack control unit 104 transmits the remaining amount and learning capacity stored in the memory 103 to the camera microcomputer 104 as remaining amount information. The control unit 114 calculates a ratio between the remaining amount of the battery pack 105 received from the battery pack control unit 104 and the learning capacity of the battery pack 105 received from the battery pack control unit 104, and subtracts a predetermined offset value from the ratio. Thus, the remaining amount used in the imaging device 123 is calculated. For example, when the ratio calculated by the battery pack control unit 104 is 15% and the predetermined offset value is 10%, the remaining amount used by the imaging device 123 is 5% (= 15% −10%). Become.

  In step S202, the control unit 114 determines whether the remaining amount calculated in step S201 is 0% or less. When the control unit 114 determines that the remaining amount calculated in step S201 is not 0% or less, the flowchart of FIG. 2 ends. On the other hand, when the control unit 114 determines that the remaining amount calculated in step S201 is 0% or less, the process proceeds to step S203.

  In step S203, the control unit 114 causes the display unit 118 and other display devices to display information for notifying the user that the imaging device 123 has reached the operation prohibited state for a predetermined time (for example, 10 seconds). Control. 3A and 3B show examples of information for notifying the user that the imaging device 123 has reached the operation prohibited state. FIG. 3A is an example of information displayed on a display device installed on the right shoulder of the imaging device 123, and FIG. 3B is an example of information displayed on the display unit 118. The control unit 114 displays the information and performs a process of ending main operations of the imaging device 123 such as writing to the recording medium 112 and imaging operations.

  In step S204, the control unit 114 controls each component of the imaging device 123 so as to operate in the standby mode. Here, the standby mode is characterized in that, for example, the current value is small compared to the imaging operation in a mode that operates with low power consumption such that the battery current is 100 mA or less and the current fluctuation is 100 mA or less.

  In step S <b> 205, the control unit 114 communicates with the battery pack control unit 104 to acquire the voltage of the secondary battery 101 in the battery pack 105. When it is determined that the voltage of the secondary battery 101 is equal to or lower than the end voltage (for example, 5.4 V), the control unit 114 proceeds to step S206.

  On the other hand, when the control unit 114 determines that the voltage of the secondary battery 101 exceeds the end voltage, the control unit 114 continues the standby mode of the imaging device 123, and again after a predetermined time (for example, 5 seconds) has elapsed. The process of step S205 is repeated. Here, the control unit 114 determines whether or not the voltage of the secondary battery 101 has reached the end voltage, but the battery pack control unit 104 performs this process, and the voltage of the secondary battery 101 reaches the end voltage. It is good also as a structure which notifies the control part 114 whether it did.

  In step S206, the battery pack control unit 104 uses the integrated value of the charge / discharge current stored in the memory 103 until the voltage of the secondary battery 101 reaches the end voltage as a new learning capacity. Save to.

  In step S207, the control unit 114 performs control to stop each component of the imaging device 123, and the flowchart of FIG.

  Thereby, the capacity learning of the battery pack 105 is completed in the imaging device 123, and the battery pack 105 can be detached from the imaging device 123. Here, even when the voltage of the secondary battery 101 is not equal to or lower than the end voltage, it is possible to remove the battery pack 105 from the imaging device 123 halfway. However, in this case, since the capacity learning of the battery pack 105 has not been completed, the flowchart of FIG. 2 is started when the battery pack 105 is connected to the imaging device 123 again.

  As described above, in the first embodiment, the remaining amount used in the imaging device 123 can be calculated by subtracting a predetermined offset value from the ratio between the remaining amount of the battery pack 105 and the learning capacity of the battery pack 105. it can. As a result, even when there is a divergence between the actual capacity and the learning capacity, it is possible to prevent a situation in which the imaging device 123 is suddenly prohibited from operating.

  Furthermore, in the first embodiment, the battery pack 105 can be discharged in the low power consumption mode with a small load fluctuation from the time when the imaging device 123 reaches the operation prohibited state to the end voltage of the secondary battery 101. Thereby, the capacity learning of the battery pack 105 can be performed without operating the protection circuit 108 of the battery pack 105.

[Embodiment 2]
In the first embodiment, the example in which the operation mode of the imaging device 123 automatically transitions to the mode for performing the capacity learning of the battery pack 105 after the imaging device 123 reaches the operation prohibited state has been described.

  However, in the first embodiment, there is a problem that there is no means for allowing the user to freely select whether or not the capacity learning of the battery pack 105 is performed. If the capacity learning of the battery pack 105 is performed, the charging time becomes longer by the capacity from the time when the imaging device 123 reaches the operation prohibited state until the voltage of the secondary battery 101 reaches the final voltage. There are challenges.

  In the second embodiment, an example for solving the problem of the first embodiment will be described. In the second embodiment, description of parts common to the first embodiment will be omitted, and description will be made focusing on parts unique to the second embodiment.

  First, the flow of battery check and capacity learning of the battery pack 105 in the second embodiment will be described with reference to the flowchart of FIG.

  In steps S401 to S402 in FIG. 4, the same processing as in steps S201 to S202 in FIG. 2 is executed. Further, in steps S405 to S407 in FIG. 4, the same processing as in steps S205 to S207 in FIG. 2 is executed.

  In step S <b> 403, the control unit 114 causes the display unit 118 to display information for allowing the user to select whether or not to perform capacity learning of the battery pack 105 when the imaging device 123 reaches the operation prohibited state. Take control. An example of information for causing the user to select whether or not to perform capacity learning of the battery pack 105 is shown in FIG. Thereby, the user can instruct the imaging device 123 whether or not to perform capacity learning of the battery pack 105 by operating the operation unit 119. When the user operates the operation unit 119 and selects “Yes”, the control unit 114 proceeds to step S404. When the user operates the operation unit 119 and selects “No”, the control unit 114 performs step S408. Proceed to

  In step S404, the control unit 114 provides information for notifying the user that capacity learning is being performed, a guideline for the remaining capacity learning time, the user's work after capacity learning, and the like until capacity learning is completed. Control for displaying on the display unit 118 is performed. FIG. 6 shows an example of information for notifying the user that the capacity learning is being performed, a guide for the remaining capacity learning time, the user's work after the capacity learning, and the like. Further, the control unit 114 displays the information and performs a process of ending main operations of the imaging device 123 such as writing to the recording medium 112 and imaging operations. The battery current and current fluctuation in this state are about 150 mA, which is small compared to the imaging operation.

  As described above, in the second embodiment, the remaining amount used in the imaging device 123 can be calculated by subtracting a predetermined offset value from the ratio between the remaining amount of the battery pack 105 and the learning capacity of the battery pack 105. it can. Accordingly, even when there is a divergence between the actual capacity and the learning capacity, it is possible to prevent a situation in which the imaging device 123 is suddenly prohibited from operating.

  Furthermore, in the second embodiment, the battery pack 105 can be discharged in the low power consumption mode with a small load fluctuation from the time when the imaging device 123 reaches the operation prohibited state to the end voltage of the secondary battery 101. Accordingly, the battery pack control unit 104 can perform capacity learning of the battery pack 105 without operating the protection circuit 108 of the battery pack 105.

  Furthermore, in the second embodiment, when the imaging device 123 reaches the operation prohibited state, the user can select whether or not to perform capacity learning of the battery pack 105. If the user selects not to learn the capacity of the battery pack 105, the time required for charging the battery pack 105 can be shortened.

  Furthermore, in the second embodiment, the process after the capacity learning can be displayed on the display unit 118. Accordingly, it is possible to notify the user that the capacity learning is being performed, and to notify the user what to do after the capacity learning ends.

[Embodiment 3]
In the second embodiment, the user can select whether or not to change the operation mode of the imaging device 123 to the mode for performing the capacity learning of the battery pack 105 after the imaging device 123 reaches the operation prohibited state. Explained.

  However, in the second embodiment, there is a problem that the user cannot use the imaging device 123 until the capacity learning of the battery pack 105 is completed.

  In the third embodiment, an example for solving the problem of the second embodiment will be described. In the third embodiment, description of parts common to the second embodiment will be omitted, and description will be made focusing on parts unique to the third embodiment.

  First, the flow of battery check and capacity learning of the battery pack 105 in the third embodiment will be described with reference to the flowchart of FIG.

  In steps S701 to S703 in FIG. 7, the same processes as in steps S401 to S403 in FIG. 4 are executed. Further, in steps S705 to S707 in FIG. 7, the same processing as in steps S405 to S407 in FIG. 4 is executed.

  In step S <b> 704, control is performed to display on the display unit 118 information for notifying the user that the capacity learning is being performed and the functions that can be executed by the imaging device 123 during the capacity learning. 8A and 8B show examples of information for notifying the user of the capacity learning and the functions that can be executed by the imaging device 123 during the capacity learning.

  In the third embodiment, the user can use some of the functions of the imaging device 123 even during capacity learning. Specifically, the control unit 114 determines the battery current and the current fluctuation so that the protection circuit 104 does not operate until the voltage of the battery pack 105 reaches the end voltage after the imaging device 123 reaches the operation prohibited state. Allows operation lower than a predetermined value. Functions that can be executed during capacity learning are, for example, functions in which the battery current and the current fluctuation are 300 mA or less. The display on the display unit 118 of the menu screen, the display on the display unit 118 of the captured image, and the like are functions that can be executed during capacity learning.

  FIG. 8A is also an example of a menu screen for changing the setting of the built-in strobe function.

  The flash mode and dimming correction settings of the built-in flash can be selected, but the test flash with the built-in flash is grayed out so that it cannot be selected. This is because the charging current for the light emission operation of the built-in strobe is larger than a predetermined value (for example, 1 A).

  In FIG. 8A, when the user operates the operation unit 119 and selects an icon displayed as “learning” at the lower right of the screen displayed on the display unit 118, the screen transitions to the screen in FIG. It is possible to check the capacity learning status at any time.

  In addition, when the user tries to perform an imaging operation with the operation unit 119 during capacity learning, the control unit 114 displays information for notifying the user that the imaging operation cannot be performed as illustrated in FIG. Control for displaying on the unit 118 is performed.

  As described above, in the third embodiment, the remaining amount used in the imaging device 123 can be calculated by subtracting a predetermined offset value from the ratio between the remaining amount of the battery pack 105 and the learning capacity of the battery pack 105. it can. Accordingly, even when there is a divergence between the actual capacity and the learning capacity, it is possible to prevent a situation in which the imaging device 123 is suddenly prohibited from operating.

  Furthermore, in the third embodiment, the battery pack 105 can be discharged in the low power consumption mode with a small load fluctuation from the time when the imaging device 123 reaches the operation prohibited state to the end voltage of the secondary battery 101. Thereby, the capacity learning of the battery pack 105 can be performed without operating the protection circuit 108 of the battery pack 105.

  Furthermore, in the third embodiment, when the imaging device 123 reaches the operation prohibited state, the user can select whether or not to perform capacity learning of the battery pack 105. If the user selects not to learn the capacity of the battery pack 105, the time required for charging the battery pack 105 can be shortened.

  Furthermore, in the third embodiment, the process after the capacity learning can be displayed on the display unit 118. Accordingly, it is possible to notify the user that the capacity learning is being performed, and to notify the user what to do after the capacity learning ends.

  Furthermore, in the third embodiment, the control unit 114 permits the operation in the operation mode in which the battery current and the current fluctuation have little influence on the capacity learning even during the capacity learning. Therefore, it is possible to continue using some functions of the imaging device 123.

  In addition, this invention is not limited to said Embodiment 1, 2, and 3, If it is the range of the summary of invention, various changes or corrections can be added to Embodiment 1, 2, and 3. FIG.

105 battery pack, 123 imaging device

Claims (3)

A secondary battery; current detection means for detecting a charge / discharge current of the secondary battery; and storage means for storing a learning capacity corresponding to a dischargeable capacity of the secondary battery from a fully charged state to a discharge end state. An imaging device connectable to a battery pack having an update means for updating the learning capacity when the secondary battery is in an end-of-discharge state,
After reaching the operation prohibition state of the first operation mode of the imaging device, an operation mode in which the amount of current flowing through the secondary battery and the amount of current fluctuation are smaller than a predetermined value is permitted, and until the discharge end state of the secondary battery. An image pickup apparatus that shifts to an operable second operation mode. Selection means capable of selecting whether or not the imaging device shifts to the second operation mode when the battery pack connected to the imaging device reaches the operation prohibited state of the first operation mode When,
The operation mode notifying unit for notifying the user that the imaging apparatus is operating in the second operation mode when the imaging apparatus is operating in the second operation mode. The imaging apparatus according to 1.   The imaging apparatus according to claim 1, further comprising an operable mode notifying unit that notifies the user of an operable mode while the imaging apparatus is operating in the second operation mode.