JP2008301591A - Method and apparatus for determining battery reverse connection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means that makes it possible to prevent damage to a battery due to charging of an internal battery by an external battery or an erroneous connection of the internal battery and to lengthen the battery life when the internal battery and the external battery are used in parallel. <P>SOLUTION: A diode D1 is placed between the (-) terminal 3b of an internal battery 1 and ground in the forward direction of the battery. A diode short-circuit circuit 4 is provided in parallel with this diode D1. A reverse connection detection circuit 7 is provided for detecting the voltage across the diode D1. When the reverse connection detection circuit 7 detects that the voltage across the diode D1 is equal to lower than a predetermined voltage value, it determines the connection of the internal battery to be correct. The diode short-circuit circuit 4 is controlled to short-circuit both ends of the diode D1 and bring a load circuit 11 into an operating state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a device that can be used by connecting a battery in parallel to the outside in addition to the built-in battery, and relates to a method and apparatus for determining whether the polarity of the built-in battery is correctly attached and preventing reverse connection. .

  In recent years, small internal batteries, such as AAA batteries, have been installed in portable audio devices to reduce the size of the housing, and when long-term use is desired, an external battery case can be installed to provide a larger capacity than the internal battery. A large AA battery, for example, is used as an external battery and is set so that it can be used for a long time.

  In such a case, current flows from an external, for example, AA battery to an internal, for example, an AAA battery as shown in FIG. 4 due to the difference in internal resistance of the battery, and the internal battery may be charged. .

  Also, if the internal battery and external battery are primary batteries and the external battery voltage (battery C + battery D) is higher than the internal battery voltage (battery A + battery B ... when two batteries are used in series), then the internal battery Current flows through the battery, both of which damage the built-in battery and cause liquid leakage.

  Also, as shown in FIG. 5, when the built-in battery A is connected so that the plus and minus are reversed, the battery B is charged with the total battery of the battery A + the battery C + the battery D, and the battery B leaks or ruptures. It becomes dangerous.

  Also, as shown in FIG. 6, if the positive and negative of the built-in battery B are connected in reverse, the battery A is charged with the total battery B + battery C + battery D, and the battery A leaks or ruptures, which is extremely dangerous. It becomes a state.

  As a countermeasure, even if the diode D1 is inserted in the forward direction of the batteries A and B as shown in FIG. 7 and either the battery A or the battery B is connected reversely as shown in FIG. There is a method of preventing current from flowing through B.

  There is a method of preventing an accident when a reverse connection as shown in FIG. 5 or FIG. 6 is inserted by inserting a fuse (not shown) instead of the diode D1, but a countermeasure when a weak current flows in a normal connection as shown in FIG. I can't.

In order to cope with such a problem, a method as shown in Patent Document 1 has also been proposed.
JP-A-10-224999

  For example, when the load circuit can be used up to 1.5V, in the state where there is no diode D1 as shown in FIG. 4, it can be used until the total of the built-in batteries reaches 1.5V, but the diode D1 is inserted as shown in FIG. Since the voltage drop of the diode D1 occurs, when the voltage drop of D1 is 0.6V, the battery can be used only up to 2.1V at both ends of the battery, and the battery life is shortened.

  In addition, since the voltage drop of the diode D1 varies depending on the current flowing through the diode D1, there is a problem that the accuracy of the remaining battery level is deteriorated. Further, there remains a problem that it is difficult to notice the positive and negative polarity errors of the internal battery A and the internal battery B.

  Moreover, the thing of patent document 1 requires a diode, a switch, and a light bulb or a sounding device for each battery, and when reversely connected, the corresponding bean lamp emits light or the sounding device emits a warning sound. However, when the batteries are connected correctly, it is necessary to grasp the degree of battery consumption by pressing each switch in turn and visually checking the light emission degree of the bulb.

  The present invention inserts a diode in series with the built-in battery to prevent damage to the battery due to the high voltage of the external battery or reverse connection of the built-in battery, and in order to prevent loss due to the voltage drop of this diode, Determine the connection of the built-in battery according to whether the voltage between the terminals of the connected diode is within the specified voltage range, and when the connection is correct, eliminate the loss due to the voltage drop of the diode by short-circuiting between the diode terminals, An object of the present invention is to provide a battery reverse connection determination method and a battery reverse connection determination device that can effectively use battery voltage and improve battery life.

  In order to cope with this problem, the battery reverse connection determination device according to the present invention includes a diode connected in series so as to be forward in the normal connection direction of the first battery, and a series circuit of the first battery and the diode. A second battery connected in parallel; a reverse connection detection circuit that detects whether or not a voltage between the terminals of the diode is within a predetermined voltage range; and a diode short circuit that short-circuits between the terminals of the diode. When the reverse connection detection circuit detects that it is within a predetermined voltage range, it is determined that the connection of the first battery is correct, and the diode short circuit is turned on.

  In order to cope with this problem, the battery reverse connection determination method of the present invention includes a diode connected in series so as to be forward in the normal connection direction of the first battery, and a series circuit of the first battery and the diode. A second battery connected in parallel to each other, a reverse connection detection circuit that detects whether or not a voltage between the terminals of the diode is within a predetermined voltage range, and a diode short circuit that short-circuits between the terminals of the diode And a detecting step for detecting whether or not the voltage between the terminals of the diode is within a predetermined range, and the connection of the first battery is correct when the voltage between the terminals of the diode is within the predetermined range. And a short-circuiting step for short-circuiting between the terminals of the diode when it is determined that the connection of the first battery is correct in the determination step. It is intended.

  According to the battery reverse connection determination method and the battery reverse connection determination device of the present invention, in order to prevent damage to the battery due to the high voltage of the second battery or the reverse connection of the first battery, the battery is connected in series with the first battery. In order to prevent loss due to the voltage drop of the inserted diode, the connection of the first battery is determined depending on whether or not the voltage between the terminals of the diode connected in series with the first battery is within a predetermined voltage range. When it is correct, the loss due to the voltage drop of the diode can be eliminated by short-circuiting the terminals of the diode, the battery voltage can be used effectively, and the battery life can be improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a battery reverse connection discriminating apparatus according to an embodiment of the present invention, FIG. 2 is an operation flowchart thereof, and FIG. 3 is an explanatory diagram showing a difference in battery life of an internal battery due to the operation of the battery reverse connection discriminating apparatus. Indicates.

  In FIG. 1, for example, an AAA battery A and a battery B can be mounted in series as an internal battery 1 that is a first battery, or a second battery using an external battery case (not shown) or the like. As an external battery (external battery) 2, for example, an AA battery C and a battery D can be mounted, and these are connected to the main circuit via the battery terminal 3. The internal battery terminal (+) 3a of the battery terminal 3 is connected to the (+) terminal 1a of the battery A, and the internal battery terminal (−) 3b is connected to the (−) terminal 1b of the battery B. The charging terminal 3c is connected to the terminal 1c only when the batteries A and B are charging batteries. The external battery terminal (+) 3d is connected to the (+) terminal 2a of the battery C of the external battery 2, and the external battery terminal (−) 3e is connected to the (−) terminal 2b of the external battery 2.

  The diode short circuit 4 is connected to both ends of the diode D1, the cathode of the diode D1 is connected to the anode of the FET Q1, and the anode of the diode D1 is connected to the cathode of the FET Q1. The cathode of the diode D1 is connected to the internal battery terminal (−) 3b, so that the diode D1 is connected in series with the internal batteries A and B in the forward direction.

  The cathode of the diode D1 is grounded through a series circuit of resistors R1 and R2, and the middle point of the resistors R1 and R2 is connected to a voltage detection terminal 5a of a microcomputer (hereinafter referred to as microcomputer) 5 for voltage detection. Yes. The display device 6 uses a liquid crystal display device, an LED, or the like, and displays at least a reverse connection state of a battery, which will be described later, under the control of the microcomputer 5. Thus, the resistors R1, R2, the microcomputer 5, and the display device 6 constitute a reverse connection detection circuit 7.

  The anode of the diode D1 of the diode short circuit 4 is normally grounded by the switch SW1 of the DC input jack section 8, and when an external input jack (not shown) is connected to the DC input jack section 8, the diode short circuit 4 is connected by the interlocked switch SW1. Is disconnected from the device.

  When the built-in battery 1 is a charging battery, the charging current control circuit 9 controls the charging current of the charging battery through the charging terminal 3c through the transistor Q2 whose emitter is grounded by the resistor R3, and the regulator control circuit 10 has a DC input. The voltage is adjusted via the transistor Q3 when an external power supply is input from the jack section 8, and none of them is included in the operation to be described in the present embodiment.

  The load circuit 11 is a built-in battery 1 and an external battery 2, or a portable audio device that operates by obtaining power from an external power source.

  The operation of the battery reverse connection determination device of the present embodiment configured as described above will be described below assuming that the connection polarity of the external battery is correct using the flowchart of FIG. First, the operation of the reverse connection detection circuit 7 is as follows. In step S1, the microcomputer 5 checks the voltage of the terminal 5a, and if the positive and negative of the batteries A and B of the built-in battery 1 are normally attached, the battery terminal 3 The terminal 3b becomes the cathode voltage of D1, and is determined by the forward voltage of the diode D1 being used, which is normally 0.6 V or less. For example, when the resistor R1 is 150 KΩ and R2 is 100 KΩ, the microcomputer 5 Is determined to be 0.6V × {100 ÷ (150 + 100)} = 0.24V, and if the voltage detection terminal 5a of the microcomputer 5 is equal to or less than a predetermined voltage obtained by adding an error to 0.24V, the predetermined voltage It can be determined that the battery is correctly attached as being within the range. If positive and negative of the batteries A and B of the built-in battery 1 are judged to be normal, the control output 5b of the microcomputer 5 is set to H output in step S2, and the FET Q1 as means for connecting the anode and cathode of the diode D1 is turned on. Thus, the diode short circuit 4 is shifted to the operating state, and the load circuit 11 is shifted to the operating state in step S3.

  In step S1, when the voltage detection terminal 5a of the microcomputer 5 exceeds a predetermined voltage, either the battery A or B of the built-in battery 1 or both positive and negative are mounted in reverse as described below. In step S4, the control output 5b of the microcomputer 5 is set to L output, and the FET Q1 as a means for connecting the anode and cathode of the diode D1 is kept off, and Q1 of the diode short circuit 4 is not turned on.

  In step S5, the microcomputer 5 controls the load circuit 11 to remain in a non-operating state, and in step S6, the display device 6 is used to display that there is an abnormality in battery connection.

  Explaining a specific numerical example when the connection of the built-in battery is wrong, the voltage of the diode D1 when the voltage of the battery alone is 1.5 V and either plus or minus of the battery A or B is reversed is installed. The cathode side voltage is 1.5V + 1.5V + 1.5V−1.5V = 3V. The voltage determined by the microcomputer 5 is 3V × {100 ÷ (150 + 100)} = 1.2V when R1 is 150 KΩ and R2 is 100 KΩ.

  In addition, when the battery voltage is lowered to 0.75 V per battery and either the positive or negative of the internal battery A or the internal battery B is mounted in reverse, the anode side voltage of D1 is 0.75 V + 0.75 V + 0 .75V-0.75V = 1.5V. The voltage determined by the microcomputer is 1.5 V × {100 ÷ (150 + 100)} = 0.6 V when R1 is 150 KΩ and R2 is 100 KΩ.

  Furthermore, when the voltage of the battery alone is 1.5V and both the battery A and the battery B are positively and negatively attached, the cathode side voltage of the diode D1 is 1.5V + 1.5V + 1.5V + 1.5V = 6V = 6V become. The voltage determined by the microcomputer 5 is 6 V × {100 ÷ (150 + 100)} = 2.4 V because R1 is 150 KΩ and R2 is 100 KΩ.

  Furthermore, when the voltage of the single battery is 0.75 V and both the batteries A and B are positively and negatively attached, the cathode side voltage of D1 is 0.75 V + 0.75 V + 0.75 V + 0.75 V = 3 V . The voltage determined by the microcomputer 5 is 3V × {100 ÷ (150 + 100)} = 1.2V when R1 is 150 KΩ and R2 is 100 KΩ.

  As described above, when positive or negative of at least one of the built-in batteries A and B or both of them are mounted in reverse, the voltage becomes 0.6V to 2.4V, so that the determination by the microcomputer 5 has an error of 0.24V. When the voltage is equal to or higher than the applied voltage, it can be determined that the plus and minus of the built-in batteries A and B are reversed.

  In FIG. 3, when the minimum operating voltage of the load circuit is 1.5V and the voltage of the single battery is 1.5V, two internal batteries and two external batteries are connected in series, and the diode D1 is still inserted. The voltage (V) of the built-in battery 1 gradually decreases with the passage of time (t) from the initial voltage V1, and when the voltage reaches V2 of 2.1 V, the load circuit becomes inoperative. It was possible to operate up to the point of voltage V3. As described above, according to the battery reverse connection determination method and the battery reverse connection prevention device of the present invention, the voltage loss due to the voltage drop of the diode D1 can be eliminated and the voltage across the battery can be fully used. -10% improvement.

  Since the voltage drop of D1 varies depending on the current flowing through D1, there is a problem that the accuracy of the remaining battery capacity is deteriorated. However, when the power supply that is normally connected is turned on, the anode and cathode of D1 are connected. Loss due to the descent is eliminated, and the accuracy of the remaining battery level is improved.

  As described above, according to the present embodiment, by detecting the terminal voltage of D1 with the diode D1 inserted, it is possible to easily detect erroneous mounting of the internal battery, and if the internal battery is correctly connected, the diode By short-circuiting the diode D1 by the short circuit 4, the voltage drop due to D1 can be eliminated and the substantial battery life can be extended.

  In the above-described embodiment, the external battery is normal and it has been described that the built-in battery is erroneously mounted. However, the circuit connection is switched between the internal battery and the external battery, and the diode D1 is connected in series to the external battery. If this is done, it is possible to detect whether there is an erroneous connection of the external battery (in this case, the first battery) when the internal battery (in this case, the second battery) is normal. Easy.

  Further, the battery type, the resistance value, the voltage value, and the like used for the description in the above embodiment are all examples, and are not limited thereto.

  According to the battery reverse connection determination method and battery reverse connection determination device of the present invention, the battery is prevented from being damaged when the voltage of the external battery is high or the internal battery is reversely connected, and a warning is issued if there is an incorrect battery connection. In addition, it is possible to ensure the safety of the device, such as not to operate the circuit, and to use the battery voltage effectively to improve the battery life.

The block diagram of the battery reverse connection discrimination | determination apparatus in one Embodiment of this invention. The operation flowchart Explanatory drawing which shows the difference in the battery life of an internal battery similarly by operation | movement of a battery reverse connection discrimination device Block diagram when the built-in batteries A and B are installed correctly Block diagram when built-in battery A is loaded with the plus and minus reversed, and built-in battery B is installed correctly Block diagram when the built-in battery B is mounted with the positive and negative reversed, and the built-in battery A is mounted normally Block diagram when diode D1 is inserted in series and built-in batteries A and B are installed normally Block diagram when the diode D1 is inserted in series and the built-in battery A is mounted with the plus and minus reversed, and the built-in battery B is mounted normally Block diagram when the diode D1 is inserted in series and the built-in battery B is mounted with the positive and negative reversed, and the built-in battery A is mounted normally Explanatory drawing which shows the relationship between the load circuit voltage and internal battery voltage when the diode D1 is inserted in series

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Built-in battery 2 External battery 3 Battery terminal 4 Diode short circuit 5 Microcomputer 6 Display apparatus 7 Reverse connection detection circuit 8 DC input jack part 9 Charging current control circuit 10 Regulator control circuit 11 Load circuit

Claims (8)

A diode connected in series so as to be forward in the normal connection direction of the first battery;
A second battery connected in parallel to a series circuit of the first battery and the diode;
A reverse connection detection circuit for detecting whether the voltage between the terminals of the diode is within a predetermined voltage range;
A diode short circuit for short-circuiting between the terminals of the diode;
When the reverse connection detection circuit detects that it is within a predetermined voltage range, it is determined that the connection of the first battery is correct and the diode short circuit is turned on. . When the reverse connection detection circuit determines that the connection of the first battery is correct, the reverse connection detection circuit controls the load circuit to be operated by the first battery and the second battery to be in an operating state. The battery reverse connection determination device according to claim 1, wherein: 3. The battery reverse connection determination device according to claim 1, wherein the reverse connection detection circuit includes a display device that displays whether or not the battery is connected correctly. The battery reverse connection determination device according to claim 1, wherein the first battery is a built-in battery, and the second battery is an external battery. A diode connected in series so as to be forward in the normal connection direction of the first battery;
A second battery connected in parallel to a series circuit of the first battery and the diode;
A reverse connection detection circuit for detecting whether the voltage between the terminals of the diode is within a predetermined voltage range;
With a diode short circuit that short-circuits between the terminals of the diode,
A detection step of detecting whether or not a voltage between terminals of the diode is within a predetermined range;
A determination step of determining that the connection of the first battery is correct when the voltage between the terminals of the diode is within a predetermined range;
A battery reverse connection determination method comprising: a short circuit step of short-circuiting between the terminals of the diode when it is determined in the determination step that the connection of the first battery is correct. The determination step further includes a step of controlling the load circuit to be operated by the first battery and the second battery to be in an operating state when it is determined that the connection of the first battery is correct in the determination step. The battery reverse connection determination method according to claim 5. The battery reverse connection determination method according to claim 5, further comprising a step of displaying that when it is determined that the connection of the first battery is incorrect in the determination step. The battery reverse connection determination method according to claim 5, wherein the first battery is a built-in battery, and the second battery is an external battery.

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