JP2006133231A - Battery-driven device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a battery replaceable while being kept supplied with power. <P>SOLUTION: The battery 12 installed in a body connects to a power supply terminal 16 via a backflow prevention diode 14 and a battery pack 18 connects to the power supply terminal 16 via an external connection terminal 24. A microcomputer 30 causes a switch 28 to select a reference voltage Va when the battery pack 18 is not connected and to select a reference voltage Vb (>Va) when the battery pack 18 is connected. A comparison circuit 26 compares the voltage of the power supply terminal 16 to the reference voltage coming from the switch 28, and sets outputs at high level when the voltage of the power supply terminal 16 is lower. The microcomputer 30 causes a character information generation circuit 32 to generate character information indicative of battery consumption according to the high level outputs of the comparison circuit 26. The character information is applied to a video monitor 40 via an adder 36 and a video output terminal 38 to display video. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a battery-driven device, and more specifically, to a battery-driven device such as a portable device or a small electronic device that operates using a battery as a power source.

  FIG. 5 shows a schematic block diagram of a conventional example of a battery management portion of a portable magnetic recording / reproducing apparatus that can use a plurality of batteries. Reference numeral 110 denotes a main body of the magnetic recording / reproducing apparatus. A battery 112 is mounted on the main body 110, and its output voltage is connected to the power supply terminal 116 via the backflow prevention diode 114. The externally connected battery pack 118 has a configuration in which two batteries 120a and 120b are connected in parallel by backflow prevention diodes 122a and 122b, and its output voltage is connected to the power supply terminal 116 via the external connection terminal 124. . In FIG. 5, the battery 112 mounted on the main body and the external battery pack 118 are connected to the power supply terminal 116 in parallel. The power supply terminal 116 is connected to a power input terminal of each part of the main body 110. Thus, power necessary for operation is supplied to each part of the main body 110 from the battery 112 and / or the battery pack 118 mounted on the main body.

  The voltage of the power supply terminal 116 is applied to one input of the comparison circuit 126, and the reference voltage Vref corresponding to the lowest battery output voltage value at which the main body 110 operates reliably is applied to the other input. The comparison circuit 126 compares both voltages, and when the voltage at the power supply terminal 116 becomes lower than the reference voltage Vref, the output is set to a high level. When the output of the comparison circuit 126 becomes high level, the microcomputer 128 causes the character information generation circuit 130 to generate character information that warns the user that the battery is exhausted.

  The recording / reproducing circuit 132 is a circuit that records and reproduces video and audio on a recording medium, and outputs a video signal recorded on the recording medium, a video signal reproduced from the recording medium, and other video signals to the adder 134. The output of the character information generation circuit 130 is also applied to the adder 134, and the adder 134 synthesizes or superimposes the character information from the character information generation circuit 130 on the video signal from the recording / reproduction circuit 132. . The output of the adder 134 is applied to the video monitor 138 via the video output terminal 136.

  When power is held in one of the battery 112 and the battery pack 118 and the voltage at the power supply terminal 116 is higher than the reference voltage Vref, the output of the comparison circuit 126 remains at a low level, and the microcomputer 128 The character information generating circuit 130 is not allowed to output character information that warns of battery consumption.

  Thereafter, when both the battery 112 and the battery pack 118 are consumed and the voltage of the power supply terminal 116 becomes lower than the reference voltage Vref, the output of the comparison circuit 126 becomes high level. In response to this, the microcomputer 128 The information generation circuit 130 is made to output character information for warning of battery consumption. The warning character information output from the character information generation circuit 130 is applied to the monitor 138 via the adder 134 and the video output terminal 136 and displayed as a video. For example, a warning as shown in FIG. 6 is displayed on the screen of the monitor 138. Such a warning may be displayed not on the monitor screen but on the operation panel surface.

  In the conventional example, the reference voltage Vref is set to the lowest battery voltage at which the entire apparatus can operate without problems so that the operation time of the magnetic recording / reproducing apparatus 110 can be made as long as possible. That is, the reference voltage Vref is usually set to a voltage when the battery is almost exhausted. Therefore, in the conventional example, the battery 112 or the battery pack 118 cannot be replaced while the magnetic recording / reproducing apparatus 110 is kept operating after the warning message for battery consumption is output. This is because if the battery 112 (or battery pack 118) is to be replaced while the magnetic recording / reproducing apparatus 110 is operating, the remaining battery pack 118 (or battery) is removed when the battery 112 (or battery pack 118) is removed. 112) the output current rapidly increases, and the voltage at the power supply terminal 116 rapidly decreases due to the voltage drop of the battery internal resistance and the wiring resistance. This is because it is impossible to secure power necessary for the operation of the device 110.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a battery-driven device that enables battery replacement while operating.

  The battery drive device according to the present invention is, for example, a battery drive device capable of using a first battery and a second battery, and a connection detection means for detecting connection of the second battery, and the connection detection. According to the detection result of the means, if the second battery is not connected, the first reference value is selected, and if the second battery is connected, the first reference value is selected. According to the result of the comparison means, selection means for selecting a large second reference value, comparison means for comparing the output voltages of the first and second batteries with the reference value selected by the selection means, and battery consumption according to the result of the comparison means And control means for controlling whether or not to display warning information.

  Another battery-driven device according to the present invention is, for example, a battery-driven device capable of using a first battery and a second battery, and the first battery is connected thereto. When the battery is not connected, it is determined using the first reference value whether warning information for warning of battery consumption is supplied to the display means, and the first battery and the second battery are In the case of being connected, it has a determining means for determining whether or not to supply the warning information to the display means by using a second reference value higher than the first reference value.

  According to the present invention, it is possible to prompt the user to replace the battery appropriately according to their consumption state, and it is possible to replace the battery in the power supply state. Thereby, battery exchange can be performed now appropriately.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a schematic block diagram of a first embodiment of the present invention applied to a portable magnetic recording / reproducing apparatus. Reference numeral 10 denotes a main body of the magnetic recording / reproducing apparatus, to which a battery 12 is attached. The battery 12 is connected to the power supply terminal 16 via the backflow prevention diode 14. The externally connected battery pack 18 has a configuration in which two batteries 20 a and 20 b are connected in parallel by backflow prevention diodes 22 a and 22 b, and the output voltage is connected to the power supply terminal 16 via the external connection terminal 24. . As in the conventional example, the battery 12 mounted on the main body and the external battery pack 18 are connected to the power supply terminal 16 in parallel. The power supply terminal 16 is connected to a power input terminal of each part of the main body 10. Thereby, each part of the main body 10 is supplied with power necessary for operation from the battery 12 and / or the battery pack 18 mounted on the main body.

  The voltage of the power supply terminal 16 is applied to one input of the comparator circuit 26, and the voltage selected by the switch 28 from the two reference voltages Va and Vb is applied to the other input. The comparison circuit 26 compares the two input voltages, and when the voltage at the power supply terminal 16 becomes lower than the reference voltage Va or Vb selected by the switch 28, the output is made high. The reference voltage Va is set to a voltage value corresponding to the voltage of the power supply terminal 16 at which the device 10 operates reliably when the device 10 is operated only by the battery 12 without connecting the external battery pack 18. ing. The reference voltage Vb is the voltage of the power supply terminal 16 when the apparatus 10 is operated with the battery 12 and the battery pack 18 connected together, and the power supply terminal 16 when the battery pack 18 is removed from this state. Is set to a voltage obtained by adding the difference voltage from the voltage measured in step 1 to the reference voltage Va.

  When the output of the comparison circuit 26 becomes high level, the microcomputer 30 causes the character information generation circuit 32 to generate character information that warns the user of battery consumption. Although details will be described later, the microcomputer 30 detects whether or not the external battery pack 18 is connected to the external connection terminal 24 and switches the switch 28 according to the detection result. When the battery pack 18 is not connected, the switch 28 selects the reference voltage Va, and when the battery pack 18 is connected, the reference voltage Vb is selected.

  The recording / reproducing circuit 34, like the recording / reproducing circuit 132, is a circuit that records and reproduces video and audio on a recording medium. A video signal recorded on the recording medium, a video signal reproduced from the recording medium, and other video signals Is output to the adder 36. The output of the character information generating circuit 32 is also applied to the adder 36, and the adder 36 combines or superimposes the character information from the character information generating circuit 32 on the video signal from the recording / reproducing circuit 34. . The output of the adder 36 is applied to the video monitor 40 via the video output terminal 38.

  FIG. 2 is a flowchart of battery management of the embodiment shown in FIG. When a power switch (not shown) is turned on, the microcomputer 30 first detects whether or not an external battery pack 18 is connected (S1). If the battery pack 18 is not connected, the microcomputer 28 detects a reference voltage. Va is selected (S2), and when the battery pack 18 is connected, the switch 28 is made to select the reference voltage Vb (S3). Thereby, when the external battery pack 18 is not connected, the consumption of the power supply battery is determined based on the reference voltage Va, and when the battery pack 18 is connected, the power supply is determined based on the reference voltage Vb. Battery consumption is determined.

  Next, the microcomputer 30 checks the output level of the comparison circuit 26 (S4), and if it is high, causes the character information generation circuit 32 to generate warning information indicating battery consumption as shown in FIG. . The warning information output from the character information generating circuit 32 is applied to the monitor device 40 via the adder 36 and the video output terminal 38, and is displayed on the screen of the monitor device 40.

  The functions of the comparison circuit 26, the switch 28, and the reference voltages Va and Vb can be taken into the microcomputer 30. FIG. 3 is a block diagram of a schematic configuration of such a modified example. The same components as those in FIG. 1 are denoted by the same reference numerals. Reference numeral 42 denotes a microcomputer incorporating the functions of the comparison circuit 26, the switch 28, and the reference voltages Va and Vb. Reference numeral 44 denotes an A / D converter that converts the voltage of the power supply terminal 16 from analog to digital and supplies the converted voltage to the microcomputer 42. It is.

  FIG. 4 shows a flowchart of the embodiment shown in FIG. When a power switch (not shown) is turned on, the microcomputer 42 first reads the output value of the A / D converter 44 (voltage value of the power supply terminal 16) (S11). Whether or not the battery pack 18 is connected is checked (S12). If the battery pack 18 is not connected, the output value of the A / D converter 44 fetched in S11 is the reference data corresponding to the reference voltage Va. When the battery pack 18 is connected, the output value of the A / D converter 44 taken in S11 is compared with a reference data value corresponding to the reference voltage Vb (S14).

  When the output value of the A / D converter 44 captured in S11 is lower than the reference data value corresponding to the reference voltages Va and Vb (S12 and S13), the microcomputer 42 determines that the power supply battery is exhausted. The character information generating circuit 32 generates warning information indicating battery consumption as shown in FIG. The warning information output from the character information generating circuit 32 is applied to the monitor device 40 via the adder 36 and the video output terminal 38, and is displayed on the screen of the monitor device 40.

  In the embodiment shown in FIG. 1 and FIG. 3, a higher reference value is adopted when the external battery pack is connected as a reference value for determining the consumption of the power supply battery than when it is not connected. When both the battery and the external battery pack are used, a power consumption warning is output early. As a result, the battery mounted on the main body or the external battery pack can be replaced with a margin while the apparatus is operated, that is, in the power supply state.

  Next, an embodiment will be described in which the user is notified whether the battery mounted on the main body and the external battery pack (or a plurality of power supply batteries) should be replaced. FIG. 7 shows a schematic block diagram of the embodiment.

  In FIG. 7, reference numeral 210 denotes a main body of the magnetic recording / reproducing apparatus, to which a battery 212 is attached. The battery 212 is connected to the power supply terminal 216 via the backflow prevention diode 214. The externally connected battery pack 218 has a configuration in which two batteries 218 a and 218 b are connected in parallel, and the output voltage is connected to the power supply terminal 216 via the external connection terminal 220 and the backflow prevention diode 222. Similar to the embodiment described above, the battery 212 mounted on the main body and the external battery pack 218 are connected to the power supply terminal 216 in parallel. The power supply terminal 216 is connected to a power input terminal of each part of the main body 210. As a result, power required for operation is supplied to each part of the main body 210 from the battery 212 and / or the battery pack 218 mounted on the main body.

  224 is an A / D converter that converts the output voltage of the battery 212 into a digital value, 226 is an A / D converter that converts the output voltage of the battery pack 218 into a digital value, and 228 is a digital value of the voltage at the power supply terminal 216. These are A / D converters that convert values, and these digital outputs are applied to the microcomputer 230. The microcomputer 230 is also supplied with a signal indicating whether or not the battery pack 218 is connected to the external connection terminal 220. Although details will be described later, the microcomputer 230 determines whether or not to warn of the consumption of the power supply battery according to whether or not the battery pack 218 is connected and the output of the A / D converters 224, 226, and 228.

  The microcomputer 230 causes the character information generation circuit 232 to generate character information that warns the user of battery consumption under a predetermined condition that should warn of the consumption of the power battery.

  The recording / reproducing circuit 234 is a circuit that records and reproduces video and audio on a recording medium in the same way as the recording / reproducing circuits 132 and 34. The video signal is output to the adder 236. The output of the character information generation circuit 232 is also applied to the adder 236, and the adder 236 combines or superimposes the character information from the character information generation circuit 232 on the video signal from the recording / reproducing circuit 234. . The output of the adder 236 is applied to the video monitor 240 via the video output terminal 238.

  FIG. 8 shows an operation flowchart of the embodiment shown in FIG. When a power switch (not shown) is turned on, the microcomputer 230 captures the output of the A / D converter 228 (voltage of the power supply terminal 216) and stores it in the memory (S21), and the voltage value is stored only in the battery pack 218. Compared with the voltage value (reference voltage 1) of the power supply terminal 216 at which the apparatus 210 operates reliably when the apparatus 210 is operated in (S22).

  When the voltage at the power supply terminal 216 is equal to or higher than the reference voltage 1 (S22), the process returns to S21. When the voltage at the power supply terminal 216 is lower than the reference voltage 1 (S22), the microcomputer 230 causes the character information generation circuit 232 to generate character information corresponding to a warning as shown in FIG. 9 (S23). The warning information output from the character information generation circuit 232 is applied to the monitor device 240 via the adder 236 and the video output terminal 238 and displayed on the screen of the monitor device 240.

  After the warning display (S23), whether or not the external battery pack 218 is connected is confirmed by a signal from the external connection terminal 220 (S24). If the battery pack 218 is not connected (S24), the process returns to S21. If the battery pack 218 is connected (S24), the microcomputer 230 corresponds to a warning as shown in FIG. Character information to be generated is generated and displayed on the screen of the monitor device 240 (S25). This prompts the user to replace the battery pack.

  In order to confirm the replacement of the battery pack 218, the output data of the A / D converter 226 is captured (S26) and compared with the voltage value captured in S21 (S27). The capturing of the output value of the A / D converter 226 is repeated until the output value of the A / D converter 226 becomes larger than the voltage value captured in S21. If the output value of A / D converter 226 is greater than the voltage value acquired in S21, it is determined that battery pack 218 has been replaced.

  When the battery pack 218 is replaced (S27), the microcomputer 230 stores the output value of the A / D converter 226 in the memory, deletes the warning display shown in FIG. 10 (S28, S29), and shows in FIG. A battery replacement message for prompting replacement of the internal battery 212 is generated in the character information generation circuit 232 and displayed on the screen of the monitor device 240 (S30).

  In order to confirm the replacement of the battery 212, the output data of the A / D converter 224 is fetched (S31) and compared with the output value of the A / D converter 226 after the battery pack 218 is replaced (S32). S31 is repeated until it becomes larger. When the output data of the A / D converter 224 becomes larger than the output value of the A / D converter 226 after the battery pack 218 is replaced, it is determined that the battery 212 mounted on the main body has been replaced, and the message shown in FIG. 11 is displayed. Stop (S33).

  FIG. 12 shows a schematic block diagram of a modified example of the embodiment shown in FIG. Reference numeral 310 denotes a main body of the magnetic recording / reproducing apparatus, to which a battery 312 is attached. The battery 312 is connected via a backflow prevention diode 314 to a power supply terminal 316 that supplies power to the system control circuit of the device 310. The battery 312 is also connected to the contact a of the selection switch 318, and the common contact of the selection switch 318 is connected to a power supply terminal 320 that supplies power to each part of the device 310 except for the system control circuit.

  The externally connected battery pack 322 has a configuration in which two batteries 322 a and 322 b are connected in parallel, and can be connected to an external connection terminal 324. The external connection terminal 324 is connected to the power supply terminal 316 via the backflow prevention diode 326 and also connected to the b contact of the switch 318. Accordingly, power is supplied from the battery 312 and / or the battery pack 322 to the system control circuit, and power is supplied from the battery 312 or the battery pack 322 selected by the selection switch 318 to each part other than the system control circuit. .

  328 is an A / D converter that converts the output voltage of the battery 312 into a digital value, 330 is an A / D converter that converts the output voltage of the battery pack 322 into a digital value, and these digital outputs are sent to the microcomputer 332. Applied. The microcomputer 332 is also supplied with a signal indicating whether or not the battery pack 322 is connected to the external connection terminal 324. Although details will be described later, the microcomputer determines whether or not to warn of the consumption of the power supply battery according to whether or not the battery pack 322 is connected and the outputs of the A / D converters 328 and 330.

  The microcomputer 332 generates character information that warns the character information generation circuit 334 of battery consumption and prompts replacement of the battery under a predetermined condition that should warn of the consumption of the power battery.

  The recording / reproducing circuit 336 is a circuit that records and reproduces video and audio on a recording medium in the same manner as the recording / reproducing circuits 132, 34, and 234. Other video signals are output to the adder 338. The output of the character information generation circuit 334 is also applied to the adder 338, and the adder 338 combines or superimposes the character information from the character information generation circuit 334 with the video signal from the recording / reproduction circuit 336. . The output of the adder 338 is applied to the video monitor 342 via the video output terminal 340.

  FIG. 13 shows an operation flowchart of the embodiment shown in FIG. When a power switch (not shown) is turned on, the microcomputer 332 takes in the output of the A / D converter 330 (the output voltage of the battery pack 322), temporarily stores it in the built-in memory (S41), and the A / D converter 328. (Output voltage of the battery 312) is taken in and temporarily stored in the built-in memory (S42).

  It is checked whether or not the battery pack 322 is connected (S43). If it is connected, the output voltage value of the battery pack 322 fetched in S41 and the power supply terminal 320 at which the entire apparatus 310 operates reliably. It is compared with the reference value 1 corresponding to the lowest voltage value (S44). If the output voltage of the battery pack 322 is sufficient (S44), the microcomputer 332 connects the switch 318 to the b contact (S45). Thereby, electric power is supplied from the battery pack 322 to parts other than the system control circuit.

  When the output voltage of the battery pack 322 is lower than the reference value 1 (S44), the output of the A / D converter 328 (the output voltage of the battery 312) captured in S42 is compared with the reference value 1 (S46). If the output of the A / D converter 328 is greater than or equal to the reference value 1 (S46), the character information generating device 334 outputs character information indicating a battery replacement message as shown in FIG. 14 and displayed on the screen of the monitor device 342. (S47). At the same time or before and after this, the microcomputer 332 connects the switch 318 to the contact “a”, and selects the battery 312 as a power source for parts other than the system control circuit (S48).

  When the output of the A / D converter 328 is smaller than the reference value 1 (S46), the remaining amount of the battery 312 is insufficient. However, the microcomputer 332 connects the switch 318 to the contact a to connect the system. The battery 312 is selected as the power source for the parts other than the control circuit (S49), and then the character information generating circuit 334 generates the character information of the battery consumption warning message as shown in FIG. 9 (S50).

  When the battery pack 322 is not connected (S43), the microcomputer 332 compares the output of the A / D converter 328 (the output voltage of the battery 312) taken in S42 with the reference value 1 (S51). When the output of the A / D converter 328 is greater than or equal to the reference value 1 (S51), the microcomputer 332 connects the switch 318 to the contact a, and selects the battery 312 as a power source for parts other than the system control circuit (S52). . When the output of the A / D converter 328 is smaller than the reference value 1 (S51), the microcomputer 332 connects the switch 318 to the contact a and selects the battery 312 as a power source for parts other than the system control circuit (S49). Thereafter, the character information generating circuit 334 is caused to generate character information of a warning message for battery consumption as shown in FIG. 9 (S50).

  In the embodiment shown in FIGS. 7 and 12, it is possible to prompt the user to replace the batteries 212 and 312 mounted on the main body and the external battery packs 218 and 322 appropriately according to the consumption state thereof, and the apparatus is powered The battery packs 218 and 322 and the batteries 212 and 312 can be replaced while being supplied.

  Next, an embodiment in which the consumption states of a plurality of batteries are individually displayed will be described. FIG. 15 is a schematic block diagram of an embodiment applied to a camera-integrated recording / reproducing apparatus.

  FIG. 15 will be described. Reference numeral 410 denotes a main body of the camera-integrated recording / reproducing apparatus. The imaging lens 412, an imaging device 414 that converts an optical image from the imaging lens 412 into an electrical signal, and an output signal of the imaging device 414 are subjected to camera signal processing (white balance correction and gamma). The camera signal processing circuit 416 to be corrected), the recording system 418 for recording the output video signal of the camera signal processing circuit 416 on a video tape, the microcomputer 420 serving as a system control circuit for controlling the whole, and the microcomputer 420 From a character generator (CG) 422 that generates a video signal indicating a message and other information, an adder 424 that synthesizes or superimposes the output signal of the CG 422 with an output video signal of the camera signal processing circuit 416, and an adder 424 The output video signal is displayed in the image table. Comprising an electronic view finder (EVF) 426 to be.

  The main body 410 has two power supply connection terminals, and a battery 430 serving as a power supply in a normal case is connected to one of the power supply connection terminals 428a and 428b. Two batteries 434 and 436 can be connected to the other power connection terminals 432a, 432b and 432c. The terminal 432c is a common negative terminal for the terminals 432a and 432b. The battery 430 is attached to the main body 410 and is substantially directly connected to the connection terminals 428a and 428b. 432b and 432c.

  The connection terminals 428 a, 432 a, and 432 b are connected to the selection contact of the switch 440, and the common contact of the switch 440 is connected to the DC input of the DC / DC converter 442. The switch 440 can be operated by the user, and can arbitrarily select which battery 430, 434, 436 output voltage should be supplied to the DC / DC converter 442. The DC / DC converter 442 supplies a necessary power supply voltage to each part of the main body 410.

  The voltages at the connection terminals 428a, 432a, and 432b are respectively divided by resistors 444, 446; 448, 450; 452, and 454 for voltage division and applied to the A / D port of the microcomputer 420. The reason why the voltages are divided by the resistors 444, 446; 448, 450; 452, 454 is because the output voltage of the batteries 430, 434, 436 is usually higher than the power supply voltage of the microcomputer 420. Although details will be described later, the microcomputer 420 includes batteries 430, 434 and 430, 434, which are connected to the power connection terminals 428a, 428b; 432a, 432b, 432c by input voltages from resistors 444, 446; 448, 450; The output voltage of 436 and thus the remaining amount can be detected.

  When a power switch (not shown) is turned on, the DC / DC converter 442 supplies power to each part of the main body 410. The image sensor 414 converts an optical image from the photographing lens 412 into an electrical signal, and the camera signal processing circuit 416 performs camera signal processing on the output signal of the image sensor 414. The output signal of the camera signal processing circuit 416 is applied to the recording system 418 and the adder 424. The recording system 418 records the input video signal on the recording medium according to the instruction of the microcomputer 420. The microcomputer 420 also causes the CG 422 to generate an image signal of a desired character symbol as necessary. The adder 424 mixes or superimposes the image signal from the CG 422 with the output video signal of the camera signal processing circuit 416, and supplies it to the electronic view finder 426. As a result, the optical image incident on the image sensor 416, camera information, and other information are displayed on the screen of the electronic view finder 426.

  The main part of the present invention relating to the power source will be described in detail. The user can arbitrarily select which of the batteries 430, 434, and 436 is used as a power source by the switch 440. As information for the determination, the microcomputer 420 can display the following information on the screen of the electronic view finder 426.

  The microcomputer 420 outputs voltages of the power connection terminals 428a, 428b; 432a, 432b, 432c divided by the resistors 444, 446; 448, 450; 452, 454, that is, output voltages of the batteries 430, 434, 436. Compare with a predetermined reference voltage. FIG. 16 shows general discharge characteristics of the battery. Although there is a quantitative difference depending on the type of battery, any battery qualitatively exhibits discharge characteristics as shown in FIG. Therefore, the remaining amount can be estimated from the terminal voltage of the battery.

  The microcomputer 420 compares the reference value stored in advance with the input voltage value, estimates the remaining amount of each battery 430, 434, 436 to be connected, and outputs a remaining amount display image signal CG422 according to the estimated result. To generate. The output signal of the CG 422 is applied to the electric view finder 426 via the adder 424. Thereby, the remaining amount of the batteries 430, 434, and 436 is displayed in a graphic form as shown in FIG. 17, for example. In FIG. 17, the upper row displays the remaining amount of the battery 430, the middle row displays the remaining amount of the battery 434, and the lower row displays the remaining amount of the battery 436. At the same time, the battery used as a power source (as seen from the contact point to which the switch 440 is connected) may be displayed. The user can know the remaining amount of each battery 430, 434, 436 connected by looking at the display as shown in FIG. 17, and selects the battery to be used as a power source by the switch 440 based on this information. . FIG. 18 is an example of a remaining amount display when the remaining amount is divided into five levels.

  FIG. 19 is a schematic block diagram of a modification of the embodiment shown in FIG. In the embodiment shown in FIG. 19, the power connection terminals 428 a, 432 a, and 432 b are connected to the DC input of the DC / DC converter 442 via backflow prevention diodes 460, 462, 464 instead of the switch 440 of the embodiment shown in FIG. 15. Connected. The same components as those illustrated in FIG. 15 are denoted by the same reference numerals.

  In the embodiment shown in FIG. 15, since power is not supplied to the DC / DC converter 442 at the moment of switching the switch 440, there is a possibility that the photographing is interrupted. However, as shown in FIG. , 462, 464, there is no worry about that. In addition, photographing can be continuously performed when the batteries 430, 434, and 436 are replaced.

  The embodiment in which the remaining amount of each battery 430, 434, 436 is simultaneously displayed as shown in FIG. 17 has been described. The remaining amount of 436 may be displayed. In addition to displaying on the electronic view finder, it may be displayed on the display screen of the operation panel. The number of built-in or external batteries is not limited to the illustrated embodiment, and may be two or more.

It is a schematic block diagram of the first embodiment of the present invention. It is an operation | movement flowchart of the Example shown in FIG. It is a schematic block diagram of the second embodiment of the present invention. It is an operation | movement flowchart of the Example shown in FIG. It is a schematic block diagram of a prior art example. It is an example of the monitor screen which warns of exhaustion of a power supply battery. The schematic block diagram of the third embodiment of the present invention. It is an operation | movement flowchart of the Example shown in FIG. It is an example of a warning message screen of power battery consumption. It is an example of the message of battery consumption and battery pack replacement. It is an example of a message prompting replacement of a battery mounted on the main body. It is a schematic block diagram of the fourth embodiment of the present invention. It is an operation | movement flowchart of the Example shown in FIG. It is an example of a message prompting replacement of a battery pack. It is a schematic block diagram of a fifth embodiment of the present invention applied to a camera-integrated VTR. It is a discharge characteristic figure of a battery. It is an example of a display of the battery remaining amount of the Example shown in FIG. It is a transition diagram of a battery remaining charge and a display mode. It is a schematic block diagram of 6th Example of this invention.

Explanation of symbols

10: Main body of magnetic recording / reproducing apparatus 12: Battery 14: Backflow prevention diode 16: Power supply terminal 18: Battery pack 20a, 20b: Battery 22a, 22b: Backflow prevention diode 24: External connection terminal 26: Comparison circuit 28: Switch 30 : Microcomputer 32: Character information generating circuit 34: Recording / reproducing circuit 36: Adder 38: Video output terminal 40: Video monitor 42: Microcomputer 44: A / D converter 110: Main body 112 of magnetic recording / reproducing apparatus: Battery 114 : Backflow prevention diode 116: Power supply terminal 118: Battery pack 120a, 120b: Battery 122a, 122b: Backflow prevention diode 124: External connection terminal 126: Comparison circuit 128: Microcomputer 130: Character information generation circuit 132: Recording / reproduction circuit 134 : Adder 136: Video output terminal 13 : Video monitor 210: Magnetic recording / reproducing apparatus main body 212: Battery 214: Backflow prevention diode 216: Power supply terminal 218: Battery pack 218 a, 218 b: Battery 220: External connection terminal 222: Backflow prevention diode 224, 226, 228: A / D converter 230: microcomputer 232: character information generation circuit 234: recording / reproduction circuit 236: adder 238: video output terminal 240: video monitor 310: main body 312 of the magnetic recording / reproduction apparatus: battery 314: backflow prevention diode 316: Power supply terminal 318: Selection switch 320: Power supply terminal 322: Battery pack 322a, 322b: Battery 324: External connection terminal 326: Backflow prevention diode 328, 330: A / D converter 332: Microcomputer 334: Character information generation circuit 336: Recording / reproducing circuit 38: Adder 340: Video output terminal 342: Video monitor 410: Camera integrated recording / playback apparatus main body 412: Shooting lens 414: Image sensor 416: Camera signal processing circuit 418: Recording system 420: Microcomputer 422: Character generator (CG)
424: Adder 426: Electronic view finder (EVF)
428a, 428b: power connection terminal 430: batteries 432a, 432b, 432c: power connection terminals 434, 436: battery 438: external battery holder 440: switch 442: DC / DC converters 444, 446, 448, 450, 452, 454: Resistance 460, 462, 464: Backflow prevention diode

Claims (3)

A battery-driven device capable of using the first battery and the second battery,
Connection detection means for detecting connection of the second battery;
According to the detection result of the connection detection means, when the second battery is not connected, the first reference value is selected, and when the second battery is connected, the first reference value is selected. Selecting means for selecting a second reference value greater than the reference value;
Comparison means for comparing the output voltages of the first and second batteries with a reference value selected by the selection means;
A battery-driven device comprising: control means for controlling necessity of displaying warning information for warning battery consumption according to the result of the comparing means. A battery-driven device capable of using the first battery and the second battery,
When the first battery is connected but the second battery is not connected, the first reference value is used to determine whether or not warning information for warning battery consumption is supplied to the display means. If the first battery and the second battery are connected, whether or not to supply the warning information to the display means is determined by a second reference higher than the first reference value. A battery-powered device comprising determination means for determining using a value.   The battery-powered device according to claim 1, wherein the warning information is synthesized or superimposed on an image reproduced from a recording medium.

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