JP2006129544A - Charging electric apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress power consumption effectively. <P>SOLUTION: A charging electric apparatus comprises a motor switch section 56 being inserted into the power supply line of a motor 42 in order to control rotation thereof, a drive control section 58 for controlling operation of the motor switch section 56, a power supply switch section 62 operating to supply power from a secondary battery 20 to the drive control section 58 in response to operation of a trigger switch 44, and a section 22 for detecting overdischarge of the secondary battery 20. The motor 42 is rotated by operating the trigger switch 44 when the secondary battery 20 is not in overdischarge state, and rotation of the motor 42 is disabled even if the trigger switch 44 is operated when the secondary battery 20 is in overdischarge state. Driving of the drive control section 58 is stopped a predetermined time after operation of the trigger switch 44 is released. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rechargeable electric device in which power is supplied from a secondary battery to a motor by operating an operation switch.

In recent years, rechargeable electric devices such as a rechargeable electric tool that supplies power from a secondary battery to a motor have been widely used. Such a rechargeable electric device using a secondary battery includes an electric device main body such as a power tool main body, a battery pack that is attached to the electric device main body and includes a secondary battery for driving the electric device main body, It has. In addition, the secondary battery included in the battery pack is configured by stacking a plurality of cells (battery cells). The voltage of each cell is monitored, and whether at least one cell divides a predetermined voltage value. Alternatively, when the difference between the voltage values of the cells becomes larger than a predetermined value, a protection process is performed such that the protection circuit is activated and the use of the secondary battery is prohibited (for example, Patent Document 1).
JP-A-10-27630

  However, in the conventional rechargeable electric device, since it is necessary to constantly monitor the voltage value of each cell of the secondary battery, it is necessary to keep the control unit for performing the protection process in a driving state. Therefore, a standby current flows even when the rechargeable electric device is not driven. For this reason, even if the electric device main body is not driven, power consumption is made to a small extent, and the battery capacity is consumed, leading to a decrease in capacity, and depending on the type of secondary battery, the charging time is lost. When the battery is completely discharged, there is a problem that the performance of the secondary battery is deteriorated, and there is a possibility that the electric device main body cannot be used when it is desired to be used.

  This invention is made | formed in view of such a situation, and it aims at providing the rechargeable electric equipment which can suppress power consumption effectively.

  In order to achieve the above object, a first aspect of the present invention is a rechargeable electrical device in which power is supplied from a secondary battery to a motor by operating an operation switch, and is inserted in a power supply line to the motor. A motor switch unit that controls the rotation of the motor, a drive control unit that controls the operation of the motor switch unit, and the drive from the secondary battery by operating the operation switch in response to the operation. A power supply switch unit that supplies power to the control unit, and an overdischarge detection unit that detects an overdischarge state of the secondary battery, and the drive control unit, when the secondary battery is not in an overdischarge state, When the operation switch is operated, the motor switch unit is operated to rotate the motor, and when the operation switch is released, the motor switch unit is operated. While stopping the rotation of the motor, the operation of the power supply switch unit is stopped when a predetermined time has elapsed since the operation of the operation switch was released, and the power supply to the drive control unit is stopped. When the secondary battery is in an overdischarged state, the motor switch is not operated even if the operation switch is operated, thereby disabling the rotation of the motor, while the operation switch is operated. When a predetermined time has elapsed since the release, the operation of the power supply switch unit is stopped, and the power supply to the drive control unit is stopped.

  According to a second aspect of the present invention, in the first aspect, the operation of the operation switch is released when the drive control unit is in an overdischarged state during the rotation of the motor. The operation of the motor switch unit is stopped by the time before the rotation of the motor is stopped, while the operation of the power supply switch unit is stopped when a predetermined time has elapsed since the operation of the operation switch was released. It is characterized in that the power supply to the control unit is stopped.

  According to a third aspect of the present invention, the operation is controlled by the drive control unit according to the first or second aspect, and the rotation of the motor is braked and stopped by short-circuiting the voltage application terminals of the motor. A brake switch unit is provided, and the drive control unit stops the operation of the motor switch unit when the operation switch is released when the secondary battery is not in an overdischarged state. In addition, the rotation of the motor is stopped by operating the brake switch unit for a predetermined time, and the operation of the motor switch unit is performed when the secondary battery is in an overdischarged state during the rotation of the motor. The brake switch unit is not operated only by stopping.

  According to a fourth aspect of the present invention, in the device according to any one of the first to third aspects, the drive control unit is configured such that when the secondary battery is in an overdischarged state, the secondary battery is in an overdischarged state. It is characterized in that the operation of the power supply switch unit is stopped within a shorter time than the case where there is no power supply to stop the power supply to the drive control unit.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a voltage detection unit that detects a voltage across the secondary battery is provided, wherein the drive control unit is configured to control the motor. When the voltage at both ends of the secondary battery is lower than a reference value set higher than that in the overdischarged state during rotation driving, the rotation of the motor is gradually controlled by controlling the operation of the motor switch unit. It is characterized by being reduced and stopped within a predetermined time.

  According to a sixth aspect of the present invention, in the device according to the fifth aspect, when the drive control unit is gradually reducing the rotation of the motor, the rotation of the secondary battery becomes an overdischarged state. In this case, the rotation of the motor is stopped within a shorter time than when the reduction ratio is increased to be lower than the reference value.

  According to a seventh aspect of the present invention, in the method according to the fifth aspect, when the secondary battery is in an overdischarged state while the drive control unit is gradually reducing the rotation of the motor, Then, the operation of the motor switch unit is stopped to stop the rotation of the motor.

  According to an eighth aspect of the present invention, in any one of the fifth to seventh aspects, the drive control unit causes the motor to rotate as the voltage across the secondary battery decreases during operation of the operation switch. Even when the voltage across the secondary battery is recovered due to being stopped, the operation of the operation switch is once released, and then the motor is disabled to rotate unless it is operated again. It is said.

  According to the first aspect of the present invention, since the power supply to the drive control unit is stopped when a predetermined time has elapsed since the operation of the operation switch was released, unnecessary power consumption in the drive control unit is effectively reduced. In addition to being able to be suppressed, the power is supplied to the drive control unit until a predetermined time elapses after the operation of the operation switch is released, so that the drive control is performed after the operation switch is released. Thus, it is possible to reliably operate the operation unit that needs to be controlled by the unit.

  In addition, since the drive control unit is driven until a predetermined time elapses after the operation of the operation switch is released, the battery is stopped by stopping the rotation of the motor due to the secondary battery being overdischarged. Even if the voltage recovers, the motor will not rotate unless the operation switch is re-operated after the drive control unit has stopped driving, so accidents due to inadvertent start of the motor can be prevented. Can be secured.

  According to the second aspect of the present invention, when the secondary battery is in an overdischarged state during the rotation of the motor, power is supplied to the drive control unit when a predetermined time elapses after the operation switch is released. In addition to being able to effectively suppress unnecessary power consumption in the drive control unit, the rotation of the motor is stopped before the operation switch is released. Performance degradation can be effectively prevented.

  According to the invention of claim 3, when the secondary battery is not in an overdischarged state, the rotation of the motor is stopped by operating the brake switch portion when the operation of the operation switch is released. If the secondary battery becomes over-discharged while the motor is rotating, the motor stops rotating without operating the brake switch, effectively reducing the power consumption required to operate the brake switch. Can be suppressed.

  According to the invention of claim 4, when the secondary battery is overdischarged, the power supply to the drive control unit is stopped within a shorter time than when the secondary battery is not overdischarged. In addition to being able to more effectively suppress power consumption in the drive control unit, it is possible to operate an operation unit that requires control by the drive control unit after the operation of the operation switch is released as necessary. it can.

  According to the fifth aspect of the present invention, when the voltage across the secondary battery is lower than the reference value set to a higher value than in the overdischarged state during the rotation of the motor, the rotation of the motor is gradually reduced. Therefore, it is possible to make the user recognize that the secondary battery is in a state close to an overdischarged state and needs to be charged, and avoid giving the user the impression that it has failed. be able to.

  According to the sixth aspect of the present invention, when the secondary battery is in an overdischarged state while the rotation of the motor is being gradually decreased, the voltage across the secondary battery is shorter than when the voltage across the secondary battery is lower than the reference value. Since the rotation of the motor is stopped in time, not only can the user recognize that the secondary battery is in an overdischarged state and needs to be charged, but also the performance of the secondary battery will be degraded. Can be effectively prevented.

  According to the seventh aspect of the present invention, when the secondary battery is overdischarged while the rotation of the motor is being gradually reduced, the rotation of the motor is stopped at that time. Not only can the user recognize that there is a need to charge the battery in a state close to a discharged state, but it can also more effectively prevent performance degradation of the secondary battery.

  According to the eighth aspect of the present invention, even when the voltage across the secondary battery is recovered by stopping the rotation of the motor, the operation of the motor is not required unless the operation switch is once operated and then re-operated. Since rotation is disabled, an accident due to inadvertent start of rotation can be prevented in advance, and the safety of the user can be ensured.

  FIG. 1 is an external configuration diagram showing a main part of a rechargeable electric tool which is an example of a rechargeable electric apparatus according to an embodiment of the present invention. In this figure, the rechargeable electric tool 10 is composed of a battery pack 12 serving as a driving power source and an electric device main body (electric tool main body) 14 constituting a rechargeable drill driver to which the battery pack 12 is mounted. In addition, the rechargeable electric tool 10 according to the present embodiment, like a lithium ion secondary battery, has a battery pack 12 including a secondary battery that deteriorates performance when it is completely discharged and cannot be recovered. This is an example of using.

  The battery pack 12 includes a secondary battery (for example, a lithium ion secondary battery) 20 configured by connecting a plurality of cells (battery cells) in series in a housing 18 and overdischarge for detecting an overdischarge state of each cell. A main body part 24 in which the detection part 22 is housed, and a mounting protrusion part 26 that protrudes to one surface side (upper surface side) of the main body part 24 and is attached to the electric device main body 14 are provided. A plurality of electrode terminals 28 connected to the secondary battery 20 and the overdischarge detection unit 22 are provided at the tip of the mounting protrusion 26. Further, a part of the main body 24 is provided with a remaining capacity display unit 30 for displaying the remaining capacity of the secondary battery 20.

  For example, as shown in FIG. 2, the remaining capacity display unit 30 includes a plurality of (in the figure, five) LEDs 32 arranged in a line in the vertical direction, a display switch 34 for turning on and off the LEDs 32, and the like. Yes. When the display switch 34 is turned on, a predetermined LED 32 is turned on corresponding to the remaining capacity of the secondary battery 20, and when the display switch 34 is turned off, the lit LED 32 is turned off. . In this embodiment, in the case of full charge, all the LEDs 32 from the lowest stage to the uppermost stage are turned on, and the LEDs 32 are sequentially turned off from the upper stage side as the remaining capacity decreases.

  The electrical device main body 14 is formed in the grip portion 38 of the housing 36, and is disposed inside the housing 36, the mounting portion 40 to which the mounting protrusion 26 of the battery pack 12 is detachably mounted, and the battery pack 12. Motor 42 that is driven by the supply of electric power, a trigger switch 44 that is provided in the grip portion 38 of the housing 36 and that rotates the motor 42, and is driven by operating the trigger switch 44. The control circuit unit 46 and a rotating unit 48 which is rotated by the motor 42 and which is provided at the tip of the housing 36 and to which drill teeth and the like are attached are provided.

  A plurality of electrode terminals 50 connected to the trigger switch 44 and the control circuit unit 46 are disposed on the bottom of the mounting unit 40, and when the mounting protrusion 26 of the battery pack 12 is mounted on the mounting unit 40. Each electrode terminal 50 of the mounting portion 40 is pressed against each electrode terminal 28 of the mounting protrusion 26. FIG. 3 shows a state in which the battery pack 12 is mounted on the electric device main body 14.

  FIG. 4 is a block diagram illustrating a circuit configuration according to the first embodiment of the rechargeable power tool 10 in which the battery pack 12 is mounted on the electric device main body 14. In this figure, as described above, the battery pack 12 includes a secondary battery 20 configured by connecting a plurality of cells in series, and an overdischarge detection unit that detects an overdischarge state of each cell of the secondary battery 20. 22. The + terminal of the secondary battery 20, the − terminal of the secondary battery 20, and the output terminal of the overdischarge detection unit 22 are connected to the electrode terminal 28.

  The overdischarge detection unit 22 measures the voltage of each cell, and outputs a non-overdischarge signal (for example, a low signal) when all cells are in a normal state (non-overdischarge state). Is configured to output an overdischarge signal (for example, a high signal) when an overdischarge state occurs, for example, a Zener diode that generates a reference voltage by being connected to both ends of each cell, This is a well-known circuit configuration including a resistance voltage dividing circuit for detecting a voltage at both ends, a comparator to which a reference voltage generated by a Zener diode and a voltage divided by the resistance voltage dividing circuit are input.

  That is, when the divided voltage by the resistance voltage dividing circuit of the cell is in a normal state (non-overdischarge state) higher than the reference voltage, a low signal is output from the comparator of the corresponding cell, and the divided voltage is the reference voltage. When the overdischarge state is lower than that, a high signal is output from the comparator of the corresponding cell, and when even one of the plurality of cells is in the overdischarge state, the overdischarge detection unit 22 A high signal is output from the output terminal.

  Note that the overdischarge state in the present invention is a state in which discharge has progressed lower than the specified voltage value in the fully charged state, but performance deterioration that can be recovered to the specified voltage value by charging has occurred. Point to no state. When one of the plurality of cells is in an overdischarge state, an overdischarge signal is output from the overdischarge detection unit 22, and the state in which this overdischarge signal is output is the overdischarge state of the secondary battery 20. .

  As described above, the electric device main body 14 includes the motor 42, the trigger switch 44 that rotates the motor 42, and the control circuit unit 46 that is driven when the trigger switch 44 is operated. . The power supply line of the motor 42 and the control signal input line of the control circuit unit 46 are connected to the electrode terminal 50, respectively.

  The trigger switch 44 is inserted into the power supply line of the motor 42 and includes a variable resistor 54 such as a potentiometer. The trigger switch 44 is described later by rotating the operation shaft of the variable resistor 54 according to the pulling operation amount. The voltage supplied from the constant voltage source 60 is divided, and the divided voltage corresponding to the pulling operation amount is input as an operation signal to a drive control unit 58 (to be described later) of the control circuit unit 46. In addition, the trigger switch 44 rotates the motor 44 due to inertia after power supply is stopped by short-circuiting the voltage input terminals of the motor 44 when the pulling operation amount becomes zero. It is configured to brake the operation.

  The control circuit unit 46 includes a motor switch unit 56 that is a MOSFET that is a switch element with a control terminal inserted in the power supply line of the motor 42, and a drive that includes a microcomputer that controls the motor switch unit 56 and the like. The control unit 58, a constant voltage source 60 that supplies a constant voltage (for example, 5 V) to the drive control unit 58 by changing the voltage (for example, 12 V) of the secondary battery 20, and the constant voltage source 60 And a power supply switch unit 62 that controls power supply to the drive control unit 58.

  The drive control unit 58 includes a microcomputer and the like, and includes a CPU that executes arithmetic processing, a ROM that stores processing programs and data, and a RAM that temporarily stores data. . The constant voltage source 60 is constituted by a three-terminal regulator or the like.

  The power supply switch unit 62 is connected to the start switch 64 connected between the electrode terminal 50 connected to the + electrode of the secondary battery 20 and the drive control unit 58 and the + electrode of the secondary battery 20. A first switch element 66 having a control terminal made of a PNP transistor connected between the electrode terminal 50 and the constant voltage source 60, and between the control terminal (base) of the first switch element 66 and the ground Connected to the second switch element 68 with a control terminal made of an NPN transistor connected to the drive switch 58 and the control terminal (base) of the second switch element 68. The first diode 70 includes a second diode 72 connected between the drive control unit 58 and the control terminal (base) of the second switch element 68.

  Here, the activation switch 64 is interlocked with the trigger switch 44, and is turned on when the trigger switch 44 is in the operating state, and is turned off when the trigger switch 44 is in the non-operating state. The first diode 70 has an anode connected to the start switch 64 and a cathode connected to the control terminal (base) of the second switch element 68. The second diode 72 has an anode connected to the drive control unit 58 and a cathode connected to the control terminal (base) of the second switch element 68.

  The drive control unit 58 receives a detection signal output from the overdischarge detection unit 22 of the battery pack 12 and is connected to the above-described remaining capacity display unit 30 and is turned on. A timer 76 for counting the elapsed time after 64 is turned off is connected.

  The drive control unit 58 also includes a switch determination unit 78 for determining the on / off state of the start switch 64, and a start voltage for turning on the second diode 72 in response to the start switch 64 being turned on. 72, the output control unit 80 for outputting to the level 72, the level determining unit 82 for determining the voltage level output from the variable resistor 54 according to the pulling operation amount of the trigger switch 44, and the period during which the trigger switch 44 is being operated. A pulse control unit 84 for performing pulse control such as PWM (Pulse Width Modulation) control on the rotation of the motor 42 by controlling on / off of the motor switch unit 56 in accordance with the voltage level output from the variable resistor 54, a battery pack A signal discriminating unit 86 for discriminating whether a detection signal input from the 12 overdischarge detection units 22 is a high signal or a low signal; The remaining capacity of the secondary battery 20 is calculated, and the calculated remaining capacity is counted by the display control unit 88 that displays the calculated remaining capacity on the remaining capacity display unit 30, the timer control unit 90 that controls the driving of the timer 76, and the timer 76. Each function realization unit as a time discriminating unit 92 that discriminates whether or not the predetermined time has reached a predetermined time is provided.

  Note that the remaining capacity of the secondary battery 20 is calculated as follows, for example. That is, the charge amount Ca is integrated based on the amount of current flowing when the secondary battery 20 is charged, and the discharge amount Cb is integrated based on the amount of current flowing when discharging the electric device body 14 is driven. The remaining capacity Cx (Cx = Cs + Ca−Cb) of the secondary battery 20 is calculated by adding and subtracting the initial capacity Cs before charging, the accumulated charge amount Ca, and the accumulated discharge amount Cb.

  The power supply switch unit 62 configured as described above operates in the following manner together with the drive control unit 58. That is, when the trigger switch 44 is operated, the start switch 64 is turned on, whereby the first diode 70 is turned on and the second switch element 68 is turned on. As a result, the first switch element 66 is turned on. Thus, drive power is supplied from the constant voltage source 60 to the drive control unit 58.

  As a result, the drive control unit 58 is driven, and the switch determination unit 78 determines that the start switch 64 is turned on. As a result, the output control unit 80 sets the start voltage for turning on the second diode 72 to the second value. Output to the diode 72. As a result, even when the operation of the trigger switch 44 is released and the start switch 64 is turned off, so that the first diode 70 is turned off, the drive control unit 58 is maintained in the driving state.

  On the other hand, when the switch determination unit 78 determines that the operation of the trigger switch 44 is released and the start switch 64 is turned off, the timer control unit 90 outputs a drive signal to drive the timer 76, The elapsed time after the start switch 64 is turned off (that is, after the operation of the trigger switch 44 is released) is started. When the time determining unit 92 determines that a predetermined time set in advance has been reached, the output of the starting voltage for turning on the second diode 72 by the output control unit 80 is stopped. As a result, the first switch Both the element 66 and the second switch element 68 are turned off, and the power supply to the drive control unit 58 is stopped.

  In addition, after the start switch 64 is turned off (that is, after the operation of the trigger switch 44 is released), the driving of the power supply switch unit 62 is stopped until the power supply to the drive control unit 58 is stopped. The time is set to a predetermined time T1 (for example, 1 to 2 minutes) when a low signal is output from the overdischarge detection unit 22 because the secondary battery 20 is in a normal state. When the high signal is output from the overdischarge detection unit 22 because of the overdischarge state, the predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1 is set (T1> T2). ).

  FIG. 5 is a time chart for explaining the operation of the rechargeable electric tool 10 configured as described above. That is, when the secondary battery 20 is in a fully charged normal state (non-overdischarged state), the trigger switch 44 is operated by the user of the rechargeable power tool 10 (time t1), and the trigger switch 44 is activated in conjunction with the trigger switch 44. When the switch discriminating unit 78 determines that the switch 64 is turned on, the power feeding switch unit 62 is driven by operating as described above (time t1), and power supply from the constant voltage source 60 is started. The drive control unit 58 is driven.

  On the other hand, when the secondary battery 20 is in a fully charged state, a low signal is output from the overdischarge detection unit 22. For this reason, it is determined by the signal determination unit 86 that a low signal is output, and the pull operation amount of the trigger switch 44 is determined by the level determination unit 82 during this determination period. Then, the pulse control unit 84 supplies a pulse signal to the motor switch unit 56 according to the pulling operation amount, whereby the motor 42 is subjected to pulse control (PWM control). As a result, the trigger switch 44 corresponds to the pulling operation amount. The motor 42 is rotationally driven at the speed. That is, when the pulling operation amount of the trigger switch 44 is small, the motor 42 is rotationally driven at a low speed, and when the pulling operation amount is large, the motor 42 is rotationally driven at a high speed.

  When the operation of the trigger switch 44 is released and the switch discriminating unit 78 discriminates that the start switch 64 is turned off (time t2), the pulse control unit 84 sends a pulse signal to the motor switch unit 56. As a result, the motor switch unit 56 is turned off, and power supply to the motor 42 is stopped (time t2). At this time, the trigger switch 44 short-circuits the voltage input terminals of the motor 42, and the rotation of the motor 42 is braked, so that the motor 42 stops rapidly.

  On the other hand, the power supply switch unit 62 has a predetermined time T1 (for example, 1 to 2 minutes) set in advance as the elapsed time counted by the timer 76 after the operation of the trigger switch 44 is released and the start switch 64 is turned off. When it is determined by the time determination unit 92 that the output voltage has reached the output voltage, the output control unit 80 stops the output of the starting voltage, whereby the first switch element 66 and the second switch element 68 are cut off and the drive is stopped. (Time t3).

  That is, in this embodiment, since the operation of the trigger switch 44 is canceled and the power supply to the motor 42 is stopped, the drive control unit 58 is driven only for a predetermined time T1 (for example, 1-2 minutes). Unnecessary power consumption in the drive control unit 58 can be effectively suppressed. Further, since the operation of the trigger switch 44 is canceled and the power supply to the motor 42 is stopped, the drive control unit 58 is driven until a predetermined time T1 (for example, 1-2 minutes) elapses. The remaining capacity display unit 30 can be operated by operating the display switch 34 during the period.

  In addition, when the trigger switch 44 is operated again during a period when the low signal is output from the overdischarge detection unit 22 (time t4), it is determined that the start switch 64 linked to the trigger switch 44 is turned on. It is discriminated by the unit 78 and is driven by operating the power supply switch unit 62 as described above (time t4), the power supply from the constant voltage source 60 is started, and the drive control unit 58 is driven. As a result, a pulse signal is supplied to the motor switch unit 56 by the pulse control unit 84, and rotation is started by the pulse control of the motor 42 (time t4).

  However, during the operation of the trigger switch 44, the secondary battery 20 is overdischarged and a high signal is output from the overdischarge detection unit 22 (time t5), and the signal determination unit 86 indicates that this high signal has been output. When the determination is made, the supply of the pulse signal to the motor switch unit 56 is stopped (time t5) even though the trigger switch 44 is being operated (time t5), thereby stopping the power supply to the motor 42 (time). t5). In this case, since the trigger switch 44 is being operated and the voltage input terminals of the motor 42 are not short-circuited, the motor 42 is brought into a state where the brake is not applied and is stopped at a slow speed. In addition, the both-ends voltage (battery voltage) of the secondary battery 20 falls rather than the regulation voltage value Va in a full charge state, and becomes the discharge voltage value Vb in an overdischarge state.

  On the other hand, when the start switch 64 is turned off when the user releases the operation of the trigger switch 44 in response to the stop of the power supply to the motor 42 (time t6), it is determined that the switch is turned off. The timer 76 is actuated by the timer control unit 90 after being discriminated by the unit 78, and counting of the elapsed time after the start switch 64 is turned off is started. When the time determining unit 92 determines that the elapsed time counted by the timer 76 has reached a predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1, the output control unit 80 The output of the starting voltage to the second diode 72 is stopped, whereby the first switch element 66 and the second switch element 68 are cut off, and the driving of the power supply switch unit 62 is stopped (time t7).

  That is, in this embodiment, since the secondary battery 20 is in an overdischarged state and the high signal is output from the overdischarge detection unit 22, the power supply to the motor 42 is stopped. The deterioration can be prevented, and after the power supply to the motor 42 is stopped, the predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1 after the power supply is stopped. Since only the drive control unit 58 is driven, unnecessary power consumption in the drive control unit 58 can be more effectively suppressed.

  Further, since the drive control unit 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the supply of power to the motor 42 is stopped, the display switch 34 is necessary during this period. Can be operated to operate the remaining capacity display unit 30. In addition, since the drive control unit 58 is driven until a predetermined time T1 (for example, 1 to 2 minutes) elapses after the operation of the trigger switch 44 is released, the voltage across the secondary battery 20 (battery voltage). Even when the motor recovers, the motor 42 does not rotate unless the trigger switch 44 is operated again after the drive of the drive control unit 58 is stopped.

  For example, if the driving of the drive control unit 58 is stopped before the operation of the trigger switch 44 is released because the secondary battery 20 is in an overdischarged state, the rotation of the motor 42 is stopped. When the voltage across the secondary battery (battery voltage) is restored, the drive control unit 58 is re-driven and the motor 42 is rotated again. As a result, the drive control unit 58 is released until the trigger switch 44 is released. Repeats driving and stopping. On the other hand, in this embodiment, unless the operation of the trigger switch 44 is released, the drive of the drive control unit 58 is not stopped, so even when the both-end voltage (battery voltage) of the secondary battery 20 is recovered. As long as the trigger switch 44 is not operated again after the drive of the drive control unit 58 is stopped, the motor 42 does not rotate. That is, since the drive control unit 58 disables the rotation of the motor 42 unless the trigger switch 44 is operated again after the operation of the trigger switch 44 is released, an accident caused by an inadvertent rotation start of the motor 42 is prevented. And the safety of the user can be ensured.

  Returning to FIG. 5, the start switch 64 is turned on by operating the trigger switch 44 while the secondary battery 20 is in an overdischarged state and a high signal is output from the overdischarge detection unit 22. Is switched on by the operation as described above (time t8), and power supply to the drive control unit 58 is started, but the motor switch unit 56 Is not driven, the motor 42 remains stopped.

  Then, the operation of the trigger switch 44 is canceled and the start switch 64 is turned off by the switch discriminating unit 78 (time t9), and the time elapsed since the start switch 64 counted by the timer 76 is turned off. When the time determination unit 92 determines that the time has reached a predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1, the output control unit 80 outputs the starting voltage to the second diode 72. As a result, the first switch element 66 and the second switch element 68 are cut off, and the drive of the power supply switch unit 62 is stopped (time t10).

  That is, in this embodiment, the rotation of the motor 42 remains stopped even when the trigger switch 44 is operated during a period in which the secondary battery 20 is in an overdischarged state and a high signal is output from the overdischarge detection unit 22. Therefore, the performance deterioration of the secondary battery 20 can be prevented, and the drive control unit 58 can be operated only for a predetermined time T2 (for example, 0.5 to 1 minute) after the operation of the trigger switch 44 is released. Since it is not driven, unnecessary power consumption in the drive control unit 58 can be effectively suppressed. Further, since the drive control unit 58 is driven until a predetermined time T2 (for example, 0.5 to 1 minute) elapses after the operation of the trigger switch 44 is released, the display switch is displayed as necessary during this period. The remaining capacity display unit 30 can be operated by operating 34.

  FIG. 6 is a block diagram illustrating a circuit configuration according to the second embodiment of the rechargeable power tool 10 in which the battery pack 12 is mounted on the electric device main body 14. Since the circuit configuration according to the second embodiment is basically composed of the same components as the circuit configuration according to the first embodiment, components having the same functions are denoted by the same reference numerals. The detailed description will be omitted by giving, and the following description will focus on differences from the circuit configuration according to the first embodiment.

  The circuit configuration according to the second embodiment is different from the circuit configuration according to the first embodiment in that the electric device main body 14 includes a voltage detection unit 96 for detecting the voltage across the secondary battery 20, and this voltage While the voltage detected by the detection unit 96 is input to the drive control unit 58 as a detection signal, the voltage detected by the voltage detection unit 96 in the drive control unit 58 is equal to or lower than a predetermined value that is a warning value before the overdischarge state occurs. This is different from the first embodiment in that a function realization unit as a voltage discrimination unit 98 for discriminating whether or not is present is provided. Other configurations are the same as those according to the first embodiment.

  That is, in the circuit configuration according to the second embodiment, the voltage detection unit 96 is configured by a resistance voltage dividing circuit in which a plurality of resistance elements are connected in series, and the voltage detection unit including the resistance voltage dividing circuit. 96 is connected between the motor 42 side of the trigger switch 44 and the electrode terminal 50 side of the motor switch unit 56 to divide the voltage across the secondary battery 20 when the trigger switch 44 is operated. The voltage is input to the drive control unit 58 as a detection signal.

  In addition, the voltage determination unit 98 has a divided voltage input from the voltage detection unit 96 that is lower than the specified voltage value Va in which the voltage across the secondary battery 20 is fully charged, but is in an overdischarged state. It is determined whether or not the warning value Vc is higher than Vb. Note that the warning value Vc here is set in order for the user to recognize in advance that the secondary battery 20 is approaching an overdischarged state.

  FIG. 7 is a time chart for explaining the operation in the circuit configuration according to the second embodiment configured as described above. That is, when the secondary battery 20 is fully charged and in a normal state, the switch determination unit 78 determines that the trigger switch 44 is operated by the user and the start switch 64 linked to the trigger switch 44 is turned on. Then (time t1), the power supply switch unit 62 is driven by operating as described above (time t1), power supply is started from the constant voltage source 60, and the drive control unit 58 is driven. Thereby, the pulse control unit 84 performs pulse control of the motor switch unit 56 and rotation of the motor 42 is started.

  When the voltage determination unit 98 determines that the voltage across the secondary battery 20 in the normal state (non-overdischarged state) has decreased to the warning value Vc (time t2), the pulse control unit 84 The duty ratio of the control pulse supplied to the motor switch unit 56 gradually decreases until a predetermined time T3 (for example, 1 to 5 seconds) elapses, and finally the drive of the motor switch unit 56 is stopped. (Time t3). Thereby, the rotational speed of the motor 42 gradually decreases until a predetermined time T3 (for example, 1 to 5 seconds) elapses, and finally the power supply from the secondary battery 20 to the motor 42 is stopped. (Time t3).

  Here, the downward slope portion of the waveform relating to the motor switch unit 56 of the time chart shown in FIG. 7 at a predetermined time T3 indicates a state in which the duty ratio of the control pulse supplied to the motor switch unit 56 gradually decreases. The lower right slope portion of the waveform relating to the motor 42 at a predetermined time T3 indicates a state in which the rotational speed of the motor 42 is gradually decreased. In this embodiment, since the trigger switch 44 is operated even when the power supply to the motor 42 is stopped, the motor 42 is not braked, but the motor 42 gradually rotates. Therefore, the power supply is stopped immediately when the power supply is stopped.

  When the power supply to the motor 42 is stopped, the voltage across the secondary battery 20 gradually increases, and when the rotation of the motor 42 is stopped, the operation of the trigger switch 44 is released by the user. As a result, when the start switch 64 is turned off (time t4), it is determined by the switch determination unit 78 that the voltage across the secondary battery 20 returns to a value higher than the warning value Vc.

  On the other hand, the power feeding switch unit 62 has a predetermined time T2 (for example, 0.5 to 1) set in advance as the elapsed time counted by the timer 76 after the operation of the trigger switch 44 is released and the start switch 64 is turned off. Min), the output of the starting voltage by the output control unit 80 is stopped, whereby the first switch element 66 and the second switch element 68 are cut off and driven. Is stopped (time t5), and the drive controller 58 is also driven accordingly.

  That is, in this embodiment, when the voltage across the secondary battery 20 decreases to the warning value Vc while the motor 42 is driven to rotate, the rotational speed of the motor 42 gradually decreases. It is possible to recognize that the battery is approaching the overdischarge state, and it is possible to effectively prevent the performance deterioration of the secondary battery 20 by charging before the overdischarge state occurs, and the user has failed. It is possible to avoid giving an impression that it is. Further, since the drive control unit 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the operation of the trigger switch 44 is released, unnecessary power consumption in the drive control unit 58 is suppressed. Can do.

  Further, since the drive control unit 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the supply of power to the motor 42 is stopped, the display switch 34 is necessary during this period. Can be operated to operate the remaining capacity display unit 30.

  Furthermore, even if the voltage across the secondary battery 20 (battery voltage) decreases during the operation of the trigger switch 44, the rotation of the motor 42 stops, so that even if the voltage across the secondary battery 20 recovers, the trigger switch Since the drive control unit 58 is driven until a predetermined time T2 (for example, 0.5 to 1 minute) elapses after the operation of 44 is released, the drive control unit 58 is driven as described above. As long as the trigger switch 44 is not operated again after the motor is stopped, the motor 42 does not rotate. That is, even if the voltage across the secondary battery 20 is restored, the drive control unit 58 disables the rotation of the motor 42 unless the trigger switch 44 is once operated and then re-operated. As a result, an accident due to inadvertent start of rotation of the motor 42 can be prevented, and the safety of the user can be ensured.

  Returning to FIG. 7, when the trigger switch 44 is operated again (time t <b> 6) in a state where the voltage across the secondary battery 20 has returned to a value higher than the warning value Vc, the activation switch 64 that is linked to the trigger switch 44 is activated. It is determined by the switch determination unit 78 that the switch is turned on, and the power supply switch unit 62 is driven by operating as described above (time t6), power supply from the constant voltage source 60 is started, and the drive control unit 58 is activated. Driven. As a result, a pulse signal is supplied to the motor switch unit 56 by the pulse control unit 84, and rotation is started by the pulse control of the motor 42 (time t6).

  When the voltage determination unit 98 determines that the voltage across the secondary battery 20 at a value higher than the warning value Vc has decreased to the warning value Vc (time t7), the pulse control unit 84 causes the motor to The rotational speed of the motor 42 is reduced by gradually decreasing the duty ratio of the control pulse supplied to the switch unit 56 until a predetermined time T3 (for example, 1 to 5 seconds) elapses. However, it is determined by the voltage determination unit 98 that the voltage across the secondary battery 20 has reached the discharge voltage value Vb in an overdischarged state until a predetermined time T3 (for example, 1 to 5 seconds) elapses. From that point in time, the drive of the motor switch unit 56 is stopped until a predetermined time T4 (for example, 0 to 1 second) shorter than the predetermined time T3 elapses after the reduction rate of the rotation speed is increased. The power supply from the secondary battery 20 is stopped (time t8). Thereby, the motor 42 stops quickly.

  On the other hand, the operation of the trigger switch 44 is canceled, the start switch 64 is turned off (time t9), and the power supply switch unit 62 has a preset time T2 (for example, 0.5) When the time discriminating unit 92 determines that the time has reached (1 minute), the output control unit 80 stops the output of the starting voltage, and thereby the first switch element 66 and the second switch element 68 are cut off. Thus, the drive is stopped (time t10), and the drive control unit 58 is also driven accordingly.

  In other words, in this embodiment, the rotational speed of the motor 42 is gradually reduced by reducing the voltage across the secondary battery 20 to the warning value Vc during the rotation of the motor 42, and the voltage across the secondary battery 20 is further reduced. Since the rotation speed of the motor 42 is quickly stopped by the discharge voltage value Vb being in an overdischarged state, the user can recognize that the secondary battery 20 is in an overdischarged state, It is possible to effectively prevent the performance deterioration of the secondary battery 20 by charging the battery.

  Further, since the drive controller 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the power supply to the motor 42 is stopped, unnecessary power consumption in the drive controller 58 is suppressed. can do. Further, since the drive control unit 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the supply of power to the motor 42 is stopped, the display switch 34 is necessary during this period. Can be operated to operate the remaining capacity display unit 30.

  In the circuit configuration according to this embodiment, when the voltage across the secondary battery 20 does not decrease to the warning value Vc, the operation shown in the time chart of FIG. 5 is executed. The voltage detection unit 96 inputs the divided voltage from the resistance voltage dividing circuit to the drive control unit 58. However, the voltage detection unit 96 may output a high signal or a low signal by comparing with a reference voltage by a comparator. Good. In this case, the voltage determination unit 98 determines whether the signal is a high signal or a low signal. Further, when the voltage across the secondary battery 20 decreases to the warning value Vc during the rotation of the motor 42, the rotational speed of the motor 42 gradually decreases while the predetermined time T3 elapses. Instead of managing the stop of the motor 42 by time, the stop of the motor 42 may be managed by a speed reduction rate corresponding to the rotational speed of the motor 42 when the voltage across the secondary battery 20 is reduced to the warning value Vc. .

  FIG. 8 is a block diagram illustrating a circuit configuration according to the third embodiment of the rechargeable power tool 10 in which the battery pack 12 is mounted on the electric device main body 14. Since the circuit configuration according to the third embodiment is basically composed of the same components as the circuit configuration according to the first embodiment, components having the same functions are denoted by the same reference numerals. The detailed description will be omitted by giving, and the following description will focus on differences from the circuit configuration according to the first embodiment.

  The circuit configuration according to the third embodiment is different from the circuit configuration according to the first embodiment in that the motor switch unit 56 that controls the rotation of the motor 42 is configured by four switch elements, so that both forward and reverse directions are achieved. This is different from the first embodiment in that it is driven to rotate and a predetermined switch element of the four switch elements is driven to brake the rotation of the motor 42. It is the same as that relating to the form.

  That is, the circuit configuration according to the third embodiment has a connection between a connection point a connected to the + terminal side of the secondary battery 20 and a connection point b connected to the − terminal side of the secondary battery 20. A series circuit of a third switch element 100 with a control terminal made of a MOSFET and a fourth switch element 102 with a control terminal made of a MOSFET is connected, and a fifth switch element 104 with a control terminal made of a MOSFET and A motor switch unit 56 that controls the rotation of the motor 42 is configured by connecting a series circuit of sixth switch elements 106 having control terminals made of MOSFETs.

  The motor switch unit 56 configured in this manner is supplied with a pulse signal from the pulse control unit 84 of the drive control unit 58 to the control terminals (gates) of the switch elements 100, 102, 104, and 106. The motor 42 has one voltage input terminal connected to the connection point c between the third switch element 100 and the fourth switch element 102, and the other voltage input terminal connected to the fifth switch element 104 and the sixth switch element. It is connected to a connection point d of the element 106. That is, the switch elements 100, 102, 104, and 106 and the motor 42 form a bridge circuit between the connection point a and the connection point b.

  In this embodiment, the motor switch unit 56 configured as described above drives the motor 42 in the forward rotation direction by simultaneously driving the third switch element 100 and the sixth switch element 106, and By simultaneously driving the switch element 102 and the fifth switch element 104, the motor 42 is rotationally driven in the reverse direction, and by simultaneously driving the fourth switch element 102 and the sixth switch element 106, the motor The brake can be applied to the rotation of 42.

  FIG. 9 is a time chart for explaining the operation in the circuit configuration according to the third embodiment configured as described above. Here, a case where the motor 42 is rotated in the forward rotation direction will be described. That is, when the secondary battery 20 is in a fully charged normal state (non-overdischarged state), the trigger switch 44 is operated by the user of the rechargeable power tool 10 (time t1), and the trigger switch 44 is activated in conjunction with the trigger switch 44. When the switch discriminating unit 78 determines that the switch 64 is turned on, the power feeding switch unit 62 is driven by operating as described above (time t1), and power supply from the constant voltage source 60 is started. The drive control unit 58 is driven.

  On the other hand, when the secondary battery 20 is in a fully charged state, a low signal is output from the overdischarge detection unit 22. For this reason, it is determined by the signal determination unit 86 that a low signal is output, and the pull operation amount of the trigger switch 44 is determined by the level determination unit 82 during this determination period. Then, the pulse control unit 84 supplies a pulse signal to the third switch element 100 and the sixth switch element 106 according to the pulling operation amount, so that the motor 42 performs pulse control (PWM control). As a result, the motor 42 is driven to rotate at a speed corresponding to the pulling operation amount of the trigger switch 44.

  When the operation of the trigger switch 44 is released and the switch determination unit 78 determines that the start switch 64 is turned off (time t2), the third pulse of the motor switch unit 56 by the pulse control unit 84 is determined. As a result of the supply of the pulse signal to the switch element 100 and the sixth switch element 106 being stopped, the motor switch unit 56 is turned off and the power supply to the motor 42 is stopped (time t2). At this time, the pulse control unit 84 supplies a high signal to the fourth switch element 102 and the sixth switch element 106 of the motor switch unit 56 for a certain period (between times t2 and t3), so that the motor 42 The voltage input terminals are short-circuited, the brake of the rotation of the motor 42 is applied, and the motor 42 stops rapidly.

  On the other hand, the power supply switch unit 62 has a predetermined time T1 (for example, 1 to 2 minutes) set in advance as the elapsed time counted by the timer 76 after the operation of the trigger switch 44 is released and the start switch 64 is turned off. When it is determined by the time determination unit 92 that the output voltage has reached the output voltage, the output control unit 80 stops the output of the starting voltage, whereby the first switch element 66 and the second switch element 68 are cut off and the drive is stopped. (Time t4).

  That is, in this embodiment, since the operation of the trigger switch 44 is canceled and the power supply to the motor 42 is stopped, the drive control unit 58 is driven only for a predetermined time T1 (for example, 1-2 minutes). Unnecessary power consumption in the drive control unit 58 can be effectively suppressed. Further, since the operation of the trigger switch 44 is canceled and the power supply to the motor 42 is stopped, the drive control unit 58 is driven until a predetermined time T1 (for example, 1-2 minutes) elapses. During the period, the fourth switch element 102 and the sixth switch element 106 of the motor switch unit 56 can be driven to brake the rotation of the motor 42, and the remaining capacity display unit 30 can be operated by operating the display switch 34. Can be activated.

  Further, when the switch determination unit 78 determines that the start switch 64 is turned on by operating the trigger switch 44 again during the period when the low signal is output from the overdischarge detection unit 22 (time t5). ), The power supply switch unit 62 is turned on by operating as described above (time t5), and power supply to the drive control unit 58 is started. As a result, a pulse signal is supplied to the fourth switch element 102 and the sixth switch element 106 of the motor switch section 56 by the pulse control section 84, and rotation is started by the pulse control of the motor 42 (time t5). ).

  However, during the operation of the trigger switch 44, the secondary battery 20 is in an overdischarged state, a high signal is output from the overdischarge detection unit 22 (time t6), and the signal determination unit 86 indicates that the high signal is output. When the determination is made, the supply of the pulse signal to the fourth switch element 102 and the sixth switch element 106 of the motor switch unit 56 is stopped even though the trigger switch 44 is being operated. Is stopped (time t6). In this embodiment, the fourth switch element 102 and the sixth switch element 106 are not driven in order to suppress unnecessary power consumption thereafter, so that the motor 42 is not braked. It will be stopped slowly. Note that the voltage across the secondary battery 20 is lower than the specified voltage value Va in the fully charged state, and becomes the discharge voltage value Vb in the overdischarged state.

  On the other hand, when the start switch 64 is turned off by releasing the operation of the trigger switch 44 by the user in response to the stop of the power supply to the motor 42 (time t7), it is determined that the switch is turned off. The timer 76 is actuated by the timer control unit 90 after being discriminated by the unit 78, and counting of the elapsed time after the start switch 64 is turned off is started. When the time determining unit 92 determines that the elapsed time counted by the timer 76 has reached a predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1, the power supply switch unit 62 The driving is stopped (time t8).

  That is, in this embodiment, since the secondary battery 20 is in an overdischarged state and the high signal is output from the overdischarge detection unit 22, the power supply to the motor 42 is stopped. The deterioration can be prevented, and after the power supply to the motor 42 is stopped, the predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1 after the power supply is stopped. Since only the drive control unit 58 is driven, unnecessary power consumption in the drive control unit 58 can be more effectively suppressed.

  Further, since the drive control unit 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the supply of power to the motor 42 is stopped, the display switch 34 is necessary during this period. Can be operated to operate the remaining capacity display unit 30. Further, since the drive control unit 58 is driven until a predetermined time T1 (for example, 1 to 2 minutes) elapses after the operation of the trigger switch 44 is released, the drive control unit 58 as described above. The motor 42 does not rotate unless the trigger switch 44 is operated again after the drive is stopped. That is, even if the voltage across the secondary battery 20 is restored, the drive control unit 58 disables the rotation of the motor 42 unless the trigger switch 44 is once operated and then re-operated. As a result, an accident due to inadvertent start of rotation of the motor 42 can be prevented, and the safety of the user can be ensured.

  Returning to FIG. 9, the start switch 64 is turned on by operating the trigger switch 44 during a period in which the secondary battery 20 is in an overdischarged state and a high signal is output from the overdischarge detection unit 22. Is determined by the switch determination unit 78, the power supply switch unit 62 is turned on by operating as described above (time t9), and power supply to the drive control unit 58 is started. Since the third switch element 100 and the sixth switch element 106 are not driven, the motor 42 remains stopped.

  Then, the operation of the trigger switch 44 is canceled and the start switch 64 is turned off by the switch discriminating unit 78 (time t10), and the elapsed time since the start switch 64 counted by the timer 76 is turned off. When the time determination unit 92 determines that the time has reached a predetermined time T2 (for example, 0.5 to 1 minute) shorter than the predetermined time T1, the driving of the power supply switch unit 62 is stopped (time t11).

  That is, in this embodiment, the rotation of the motor 42 remains stopped even when the trigger switch 44 is operated during a period in which the secondary battery 20 is in an overdischarged state and a high signal is output from the overdischarge detection unit 22. Therefore, the performance deterioration of the secondary battery 20 can be prevented, and the drive control unit 58 can be operated only for a predetermined time T2 (for example, 0.5 to 1 minute) after the operation of the trigger switch 44 is released. Since it is not driven, unnecessary power consumption in the drive control unit 58 can be effectively suppressed. Further, since the drive control unit 58 is driven only for a predetermined time T2 (for example, 0.5 to 1 minute) after the operation of the trigger switch 44 is released, the display switch 34 is switched as necessary during this period. The remaining capacity display unit 30 can be operated by operating.

  The present invention is configured as shown in the above embodiments, and the drive control unit 58 is driven only for a predetermined time after the operation of the trigger switch 44 is released. Power consumption can be effectively suppressed. In addition, this invention is not limited to the thing of the said embodiment, The various deformation | transformation aspects as described below can be employ | adopted as needed.

  (1) In each of the embodiments described above, the rechargeable electric device is described as being configured by detachably attaching the battery pack 12 to the electric device main body 14 that is the electric power tool main body. However, the present invention is not limited to this. Absent. For example, the rechargeable electric device according to the present invention is not limited to the electric tool, and may be an electric device including the electric tool. Even if the battery pack 12 is integrated with the electric device main body 14 so as not to be detached. Good.

  (2) In each of the above embodiments, the overdischarge detection unit 22 detects the overdischarge state of each cell of the secondary battery 20, but the present invention is not limited to this. For example, an overdischarge state for each of a plurality of cell units can be detected.

  (3) In each of the embodiments described above, the start switch 64 is provided independently as interlocking with the trigger switch 44, but the present invention is not limited to this. For example, the start switch 64 may be used also as the trigger switch 44 by connecting the connections at both ends of the start switch 64 to both ends of the trigger switch 44.

  (4) In the first embodiment shown in FIG. 4 and the second embodiment shown in FIG. 6, when the operation of the trigger switch 44 is released, the trigger switch 44 connects the voltage input terminals of the motor 42. However, the present invention is not limited to this. For example, a switch element with a control terminal such as a MOSFET is connected between the voltage input terminals of the motor 42, and an on / off signal is supplied from the drive control unit 58. When the trigger switch 44 is operated, the switch element May be made non-conductive, and when the operation of the trigger switch 44 is released, the switch element is made conductive so that the voltage input terminals of the motor 42 are short-circuited.

  (5) In each of the above embodiments, the remaining capacity of the secondary battery 20 is displayed until the predetermined time elapses after the trigger switch 44 is released, or the rotation of the motor 42 is braked. However, it is not limited to this. In short, any operation unit that needs to be controlled by the drive control unit 58 after the trigger switch 44 is released until a predetermined time elapses may be used. In the present invention, the fourth operation for braking the rotation of the remaining capacity display unit 30 and the motor 42 of the secondary battery 20 to be driven until the predetermined time elapses after the trigger switch 44 is released. , The sixth switch elements 102, 106 and the like are referred to as operation parts.

  (6) The voltage detector 96 used in the circuit configuration of the second embodiment shown in FIG. 6 is not used in the circuit configurations of the other embodiments, but is not limited thereto. For example, the voltage detector 96 can be used in the circuit configuration of the first embodiment shown in FIG. 4 or the circuit configuration of the third embodiment shown in FIG. In this case, the drive control unit 58 may have a function realization unit as the voltage determination unit 98 shown in FIG. 6, and the operation similar to the operation shown in the time chart of FIG. 7 may be performed.

  (7) In each of the above embodiments, the remaining capacity display unit 30 displays the remaining capacity of the secondary battery 20 only when the display switch 34 is turned on. However, the present invention is not limited to this. For example, without using the display switch 34, the drive control unit 58 after the operation of the trigger switch 44 is released can be driven to automatically display the remaining capacity during the period. Further, the remaining capacity display unit 30 is not essential in the present invention.

It is an external appearance block diagram which shows the principal part of the rechargeable electric tool which is an example of the rechargeable electric equipment of this invention. It is a figure which shows the remaining capacity display part provided in the battery pack. It is a figure which shows the state with which the battery pack was mounted | worn with the mounting part of the electric equipment main body. It is a block diagram which shows the circuit structure which concerns on 1st Embodiment which mounted | wore the electric equipment main body with the battery pack. 5 is a time chart for explaining the operation of the circuit configuration according to the first embodiment shown in FIG. 4. It is a block diagram which shows the circuit structure which concerns on 2nd Embodiment which mounted | wore the electric equipment main body with the battery pack. It is a time chart for demonstrating operation | movement of the circuit structure based on 2nd Embodiment shown in FIG. It is a block diagram which shows the circuit structure which concerns on 3rd Embodiment which mounted | wore the electric equipment main body with the battery pack. It is a time chart for demonstrating operation | movement of the circuit structure based on 3rd Embodiment shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rechargeable electric tool 12 Battery pack 14 Electric equipment main body 20 Secondary battery 22 Overdischarge detection part 42 Motor 44 Trigger switch (operation switch)
56 Motor switch unit 58 Drive control unit 62 Power supply switch unit 96 Voltage detection unit

Claims (8)

  A rechargeable electric device that is supplied with power from a secondary battery to a motor by operating an operation switch, is inserted in a power supply line to the motor, and a motor switch unit that controls the rotation of the motor; A drive control unit that controls the operation of the motor switch unit; a power supply switch unit that supplies power to the drive control unit from the secondary battery by operating the operation switch according to an operation of the operation switch; An overdischarge detection unit that detects an overdischarge state of the battery, and the drive control unit operates the operation switch to operate the motor switch unit when the secondary battery is not in an overdischarge state. While operating and rotating the motor, the operation of the operation switch is released to stop the operation of the motor switch unit and stop the rotation of the motor. When a predetermined time has elapsed since the operation of the operation switch was released, the operation of the power supply switch unit was stopped to stop the power supply to the drive control unit, and the secondary battery was in an overdischarged state. In this case, even if the operation switch is operated, the motor switch portion is not operated to disable the rotation of the motor, while the operation switch is released when a predetermined time has passed after the operation switch is released. A rechargeable electric device characterized in that the operation of the power supply switch unit is stopped to stop the power supply to the drive control unit.   The drive control unit stops the operation of the motor switch unit until the operation of the operation switch is released when the secondary battery is in an overdischarged state during the rotation of the motor. While stopping the rotation, when a predetermined time has elapsed since the operation of the operation switch was released, the operation of the power supply switch unit is stopped and the power supply to the drive control unit is stopped. The rechargeable electric device according to claim 1.   The operation is controlled by the drive control unit, and includes a brake switch unit that applies a brake to stop rotation of the motor by short-circuiting between the voltage input terminals of the motor, and the drive control unit includes: When the secondary battery is not in an overdischarged state, the operation of the motor switch unit is stopped when the operation of the operation switch is released, and the brake switch unit is operated only for a predetermined time. When the secondary battery is in an overdischarged state during the rotation of the motor, the brake switch unit is not operated only by stopping the operation of the motor switch unit. The rechargeable electric device according to claim 1 or 2.   When the secondary battery is in an overdischarged state, the drive control unit stops the operation of the power supply switch unit within a shorter time than when the secondary battery is not in an overdischarged state. The rechargeable electric device according to any one of claims 1 to 3, wherein power supply to the control unit is stopped.   A voltage detection unit that detects a voltage across the secondary battery, wherein the drive control unit has a higher value than when the voltage across the secondary battery is in an overdischarged state during the rotation of the motor. 2. When the value is lower than a reference value set to 1, the operation of the motor switch unit is controlled to gradually reduce the rotation of the motor and stop it within a predetermined time. The rechargeable electric device according to any one of 1 to 4.   When the secondary battery is in an overdischarged state while gradually reducing the rotation of the motor, the drive control unit increases the reduction ratio of the rotation and lowers it from the reference value. 6. The rechargeable electric device according to claim 5, wherein the rotation of the motor is stopped within a short time.   When the secondary battery is in an overdischarged state while the rotation of the motor is being gradually reduced, the drive control unit stops the operation of the motor switch unit at that time and rotates the motor. The rechargeable electric device according to claim 5, wherein the rechargeable electric device is stopped.   Even if the drive control unit stops the rotation of the motor due to a decrease in the voltage across the secondary battery during operation of the operation switch, and thus the voltage across the secondary battery has recovered. The rechargeable electric device according to any one of claims 5 to 7, wherein rotation of the motor is disabled unless the operation switch is once released and then operated again.

Images