JP2007006628A - Battery charger and electric power tool set therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery charger to prevent continuation of an unexpected unrechargeable state, where the battery charger allows the control circuit to control charging current control circuit, and stops or prevents starting of the supply of the charging current to the rechargeable battery, when the temperature of the mounted rechargeable battery is higher than the temperature of battery protection. <P>SOLUTION: The battery charger 1 is provided with an ambient temperature detection circuit 13. In response to a detection result of a battery temperature detection circuit 18, the control circuit 12 charges, for instance, constant-current and constant-voltage charging; and when a detection result of the ambient temperature detection circuit 13 is higher than a determination temperature for the ambient high temperature, it displays the result on an ambient abnormal high-temperature display portion 14. Thus, with high temperature caused by exposure to direct sunlight etc. on the installation location of the battery charger 1, the detection result of the battery temperature will quickly reach higher one than that of the battery protection; and if charging is to be stopped, the system can notify this cause to the user. Thus, the user can take measures, such as moving the installation location to a shaded area. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a charger for charging a secondary battery and a power tool set in which the charger is used for charging a secondary battery of a power tool.

  In the secondary battery charger, the control means controls the charging current control means for the attached secondary battery to be charged, for example, charging is initially performed at a constant current (constant current charging). After the voltage reaches a predetermined voltage, the charging current is gradually reduced so that the voltage is maintained or not exceeded, and is reduced to approximately 0 (constant voltage charging), so that charging is performed until full charge. It is like that.

On the other hand, the battery protection temperature and the return temperature are set for each secondary battery. In Patent Document 1, the temperature detection means is built in the charger or the secondary battery, and the ambient temperature is detected and detected. When the temperature is equal to or higher than the battery protection temperature, the control means controls the charging current control means to stop the supply of the charging current to the secondary battery. Further, when the ambient temperature falls below the return temperature, charging becomes possible.
JP 7-147730 A

  However, in the above-described conventional technology, even if charging is stopped, the user does not know the cause and may determine that the failure has occurred. Also, for example, when a battery pack that has become hot due to use under heavy heat or left on a paved road is mounted on the charger, the battery pack is hot and the user may Even if it can be recognized that the battery cannot be charged, if it is left in the mounted state, it is considered that the temperature is lowered and charging is started. However, if the ambient temperature is high due to direct sunlight hitting the place where the charger is installed, the detection result of the battery temperature immediately reaches the battery protection temperature or more, and charging stops. In such a case, the state in which charging cannot be performed continues undesirably, and there is a problem that, for example, the user intends to charge at the construction site during the lunch break but cannot charge the power tool.

  The objective of this invention is providing the charger which can alert | report a cause which cannot be charged to a user, and an electric tool set using the same.

  The charger of the present invention responds to the detection result of the battery temperature detecting means built in the attached secondary battery to be charged, and if the detected temperature is equal to or higher than a predetermined first temperature, the control means In the charger that controls the control means so as not to stop or start the supply of the charging current to the secondary battery, the control means includes an ambient temperature detection means for detecting the ambient atmosphere temperature, and a display means. Responds to the detection result of the ambient temperature detecting means, and displays the fact that the ambient temperature is high when the detected temperature is equal to or higher than a predetermined second temperature.

  According to the above configuration, the control unit controls the charging current control unit, for example, initially charges the attached secondary battery to be charged with a constant current (constant current charging). After reaching a predetermined voltage, the charging current is gradually reduced so that the voltage is not maintained or exceeded, and is reduced to approximately 0 (constant voltage charging), so that the secondary battery is fully charged. In response to the detection result of the battery temperature detection means built in the battery, if the detected temperature is equal to or higher than a predetermined first temperature (battery protection temperature), supply of the charging current to the secondary battery is not stopped or started. In the battery charger as described above, an atmosphere temperature detecting means and a display means are further provided, and the control result when the detection result by the atmosphere temperature detecting means is not less than a predetermined second temperature (atmosphere high temperature determination temperature). It means, on said display means to display the ambient temperature is high.

  Therefore, direct sunlight hits the place where the charger is installed, and the detection result of the battery temperature immediately reaches the first temperature (battery protection temperature) at a high temperature, and charging stops or starts. If not, the cause can be notified to the user. As a result, the user can take measures such as moving the installation location to the shade, and can prevent the state in which charging cannot be continued undesirably without knowing the cause of charging failure. .

  Further, in the charger according to the present invention, the control means is configured such that, even if the detection result of the battery temperature detection means is lower than the first temperature, the atmosphere temperature is determined based on the detection result of the atmosphere temperature detection means. When the temperature is equal to or higher than the temperature, or when the difference between the ambient temperature and the first temperature is within a predetermined value, the charging current control means is controlled to supply the charging current to the secondary battery. It is characterized by not stopping or starting.

  According to the above configuration, as described above, the charging is stopped by detecting the battery temperature, the battery temperature is lower than the first temperature (battery protection temperature), and even if the charging is not stopped by this, Even if the ambient temperature is very high above the first temperature (battery protection temperature), or even if the ambient temperature is lower than the first temperature (battery protection temperature), the difference is only within a predetermined value. In a certain state, the control means prevents the charging current control means from stopping or starting the supply of the charging current to the secondary battery.

  Therefore, when the ambient temperature is high and charging is immediately stopped even after charging is started, charging is not stopped or started even when the battery temperature is lower than the first temperature (battery protection temperature). Therefore, the stress on the secondary battery can be further suppressed.

  Furthermore, the charger according to the present invention further includes a determination unit that determines the type of the secondary battery to be mounted and changes at least one of the first temperature or a predetermined value in accordance with the determination result. It is characterized by.

  According to the above configuration, even if the battery temperature is lower than the first temperature (battery protection temperature) and charging is not stopped by this, there is a difference between the ambient temperature and the first temperature (battery protection temperature). When the control means stops charging in a state where the value is within a predetermined value, the predetermined value serving as a determination threshold value changes according to the type of the secondary battery. Alternatively, the first temperature is changed according to the type of the secondary battery.

  Therefore, even if a plurality of types of secondary batteries can be charged with the same charger, it is possible to appropriately determine whether to stop charging each.

  Further, the charger of the present invention is characterized in that the ambient temperature detecting means is provided in the vicinity of the inlet of the outside air for cooling or in the air path from the inlet to the outlet for blowing the air for cooling the secondary battery. And

  According to the above configuration, the ambient temperature can be accurately detected without being affected by the heat generation part such as the charging current control means.

  Furthermore, the electric power tool set of the present invention is characterized by using the above charger.

  According to said structure, the electric tool set which can prevent beforehand that the state which cannot be charged cannot continue undesirably without knowing the cause which cannot be charged is realizable.

  As described above, the charger of the present invention responds to the detection result of the battery temperature detecting means built in the attached secondary battery, and the detected temperature is equal to or higher than the first temperature (battery protection temperature) that is determined in advance. And a control means for controlling the charging current control means so that supply of the charging current to the secondary battery is not stopped or started, and provided with an ambient temperature detection means and a display means, and the ambient temperature detection means If the detection result by is equal to or higher than a predetermined second temperature (atmosphere high temperature determination temperature), the control means causes the display means to display that the atmosphere temperature is high.

  Therefore, direct sunlight hits the installation location of the charger, the detection result of the battery temperature immediately reaches the first temperature (battery protection temperature) or higher at a high temperature, charging stops, If it does not start, the user can be notified of the cause. As a result, the user can take measures such as moving the installation location to the shade, and can prevent the state in which charging cannot be continued undesirably without knowing the cause of charging failure. .

  Furthermore, the power tool set of the present invention uses the charger as described above.

  Therefore, it is possible to realize a power tool set that can prevent the state where charging cannot be continued undesirably without knowing the cause of charging failure.

[Embodiment 1]
FIG. 1 is a block diagram showing an electrical configuration of a charger 1 and a secondary battery 2 in an electric tool set according to an embodiment of the present invention. The charger 1 generally converts the power from the commercial power source 3 to the attached secondary battery 2 to be charged, for example, charging at a constant current at first (constant current charging), After the charging voltage reaches a predetermined voltage, the charging current is gradually reduced so that the voltage is maintained or not exceeded, and is reduced to approximately 0 (constant voltage charging) to perform charging until full charging. This is a constant current-constant voltage charger.

  For this reason, in the charger 1, a charging current control circuit 11 that converts the power from the commercial power source 3 into desired voltage and current and applies the secondary battery 2 from the charging terminals P1 and P2, and the A control circuit 12 for controlling the charging current control circuit 11, an ambient temperature detection circuit 13 for detecting the ambient temperature around the charger 1, an ambient temperature high temperature abnormality display unit 14, a battery temperature high temperature abnormality display unit 15, A power supply circuit 16 that steps down and stabilizes electric power from the commercial power supply 3 to a desired DC voltage and supplies power to each of the above-described units is provided.

  On the other hand, the secondary battery 2 is configured to include one or more battery cells 17 connected in series and parallel and a battery temperature detection circuit 18. The battery cell 17 is connected between the charging terminals P1 and P2, and power is supplied to the battery temperature detection circuit 18 from the power supply circuit 16 via the high-side power supply terminal P3 and the GND-side charging terminal P2. Is done. The detection result of the battery temperature detection circuit 18 is input to the control circuit 12 from the detection terminal P4.

  The ambient temperature detection circuit 13 and the battery temperature detection circuit 18 are composed of a thermistor or the like, and supply the control circuit 12 with a voltage corresponding to each ambient temperature. The control circuit 12 responds to the detection result of the battery temperature detection circuit 18 at the time of charging, and enters the charge standby mode when the detected temperature is equal to or higher than the battery protection temperature, which is the first temperature set in advance, and the charging current control circuit 11 In addition, the supply of the charging current to the secondary battery 2 is not stopped or started. When the battery temperature decreases and falls below the return temperature lower than the battery protection temperature, the supply of charging current is resumed or started.

  It should be noted that in the charger 1 of the present invention, the control circuit 12 performs the constant current-constant voltage charging in response to the detection result of the battery temperature detection circuit 18 and is provided on the charger 1 side. In response to the detection result of the ambient temperature detection circuit 13, if the detected ambient temperature is equal to or higher than the ambient high temperature determination temperature, which is a predetermined second temperature, this is displayed on the ambient temperature / high temperature abnormality display unit 14. . Further, when the detection result of the battery temperature detection circuit 18 is equal to or higher than the battery protection temperature as described above, the control circuit 12 prevents the supply of the charging current from being stopped or started, and this is indicated by the battery temperature high temperature abnormality display. Display on the unit 15.

  Furthermore, even if the detection result of the battery temperature detection circuit 18 is lower than the battery protection temperature, the control circuit 12 determines that the ambient temperature is equal to or higher than the battery protection temperature based on the detection result of the ambient temperature detection circuit 13. Or when the difference between the ambient temperature and the battery protection temperature is within a predetermined value, the charging standby mode is entered, and the charging current control circuit 11 is stopped from supplying the charging current to the secondary battery 2 or While not starting, it is displayed on the atmospheric temperature / high temperature abnormality display unit 14.

  2 is a plan view showing the structure of the charger 1, FIG. 3 is a bottom view thereof, and FIG. 4 is a longitudinal sectional view thereof. An insertion hole 21 for the secondary battery 2 is formed at one end of the charger 1. When the secondary battery 2 is inserted into the insertion hole 21, the terminals P <b> 1 to P <b> 4 are electrically connected. . In the vicinity of the insertion hole 21, a discharge port 22 that blows cooling air when the secondary battery 2 is charged is provided, and on the bottom surface, a position corresponding to the discharge port 22 is provided with a cooling port. A suction port 23 for introducing outside air is provided. An air passage is formed between the discharge port 22 and the suction port 23 by a duct 24, and a fan 25 is provided in the air passage.

  The ambient temperature detection circuit 13 is provided in the suction port 23 or the air path (suction port 23 in FIG. 4). On the other hand, the charging current control circuit 11 and the control circuit 12 are provided in the remaining area in the charger 1, and the heat generated from these circuits 11 and 12 is exhausted from the vent 29 and the duct 24. The atmosphere temperature detection circuit 13 can accurately detect the ambient temperature of the charger 1 without being affected by the heat generated from the circuits 11 and 12. The ambient temperature detection circuit 13 may be provided in any of the air paths from the discharge port 22 to the suction port 23, but when the heat from the circuits 11 and 12 is exhausted by the fan 25, the suction port 23. It may be provided in.

  A display unit 26 is provided on the upper surface of the charger 1, and instructions for handling, display of completion of charging, and the like are performed. At one corner of the display unit 26, the ambient temperature / high temperature abnormality display unit 14 and the battery temperature / temperature are high. An abnormality display unit 15 is provided. These display units 14 and 15 may be configured such that the entire display unit 26 is formed of a liquid crystal panel or the like, and the characters are displayed when the abnormality should be displayed. As shown in FIG. Characters or the like may be printed on the unit 26 in advance, and display may be performed with a light emitting diode or the like. Furthermore, the display of the present invention is not limited to the visual display as described above, but may be an audio display, or a visual display and an audio display may be used in combination.

  FIG. 5 is a flowchart for explaining the operation of the control circuit 12 as described above. When the secondary battery 2 is inserted into the insertion hole 21, the process proceeds to step S <b> 1, and the ambient temperature detection circuit 13 detects the ambient temperature around the charger 1. Next, in step S2, the battery temperature detection circuit 18 detects the battery temperature. In step S3, it is determined whether or not the battery temperature is equal to or higher than the battery protection temperature. When the battery temperature is equal to or higher than the battery protection temperature, the process proceeds to step S4, and the secondary battery 2 is hot from the battery temperature high temperature abnormality display unit 15. In step S5, the process enters a standby mode, and the process ends without stopping or starting charging.

  In step S3, if the battery temperature is lower than the battery protection temperature, the process proceeds to step S6, and the ambient temperature is equal to or higher than the battery protection temperature, or the difference between the ambient temperature and the battery protection temperature is within a predetermined value. It is determined whether or not there is, and if so, the process proceeds to step S7, where it is displayed from the atmospheric temperature / high temperature abnormality display unit 14 that the installation location is high temperature, and in step S8, the standby mode is set as in step S5. Thus, the process is terminated without stopping or starting charging.

  On the other hand, in step S6, if the ambient temperature is not equal to or higher than the battery protection temperature, or the difference between the ambient temperature and the battery protection temperature is not within a predetermined value, the process proceeds to step S10, and the constant current charging is performed. Charging is started by this method, and the ambient temperature around the charger 1 is detected again by the ambient temperature detection circuit 13 in step S11. Similarly, in step S12, the battery temperature is detected again by the battery temperature detection circuit 18, and in step S13, it is determined whether or not the battery temperature is equal to or higher than the battery protection temperature. When the temperature is equal to or higher than the battery protection temperature, the process proceeds to step S14. As in step S4, the battery temperature / high temperature abnormality display unit 15 displays that the secondary battery 2 is at a high temperature. The process ends without stopping or starting.

  In step S13, if the battery temperature is lower than the battery protection temperature, the process proceeds to step S16, and the ambient temperature is equal to or higher than the battery protection temperature, or the difference between the ambient temperature and the battery protection temperature is within a predetermined value. It is determined whether or not there is, and if so, the process proceeds to step S17, and similarly to step S7, it is displayed from the atmospheric temperature / high temperature abnormality display unit 14 that the installation location is high temperature, and in step S18, the step S5 is performed. Similarly to the above, the standby mode is entered, and the process ends without stopping or starting charging.

  In step S16, if the ambient temperature is not equal to or higher than the battery protection temperature, or if the difference between the ambient temperature and the battery protection temperature is not within a predetermined value, the process proceeds to step S19, and charging is continued and constant voltage charging is performed. It is determined whether or not to end. When it should be ended, the process is ended, and when it should be continued, the process returns to step S11.

  By configuring in this way, the installation location of the charger 1 is exposed to direct sunlight, etc., and the detection result of the battery temperature immediately reaches or exceeds the battery protection temperature at a high temperature, and charging is stopped or started. If not, the cause can be notified to the user. As a result, the user can take measures such as moving the installation location to the shade, and can prevent the state in which charging cannot be continued undesirably without knowing the cause of charging failure. .

  Further, even if the battery temperature is lower than the battery protection temperature and charging is not stopped by this, even if the ambient temperature is very high above the battery protection temperature, or the ambient temperature is lower than the battery protection temperature. Even in a state where the difference is within a predetermined value, by preventing the supply of charging current from being stopped or started, the ambient temperature is high, and even if charging is started, charging is immediately stopped. In such a case, the stress on the secondary battery 2 can be further suppressed.

  Furthermore, the charging is performed by providing the ambient temperature detection circuit 13 in the vicinity of the cooling air intake port 23 or in the air path from the suction port 23 to the discharge port 22 for blowing the secondary battery cooling air. The ambient temperature can be accurately detected without being affected by the heat generation part such as the current control circuit 11.

[Embodiment 2]
FIG. 6 is a block diagram showing an electrical configuration of the charger 31 and the secondary battery 32 in an electric tool set according to another embodiment of the present invention. The charger 31 and the secondary battery 32 are similar to the charger 1 and the secondary battery 2 described above, respectively, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. It should be noted that in the charger 31 and the secondary battery 32, the secondary battery 32 is provided with a battery identification circuit 19 for identifying the type of the battery cell 17, and the battery identification circuit 19 is an identification terminal. The control circuit 42 is connected to the control circuit 42 via P5, and the control circuit 42 determines that the difference between the battery protection temperature and the ambient temperature and the battery protection temperature is within a predetermined value according to the determination result of the battery type. Or at least one of a predetermined value that is a determination threshold value for determining whether or not.

  The battery identification circuit 19 stores a voltage dividing resistor corresponding to the type of the battery cell 17, and even if a predetermined constant voltage is applied from the power supply circuit 16, the voltage dividing ratio is different, so that the identification terminal The voltage input from P5 to the control circuit 42 changes. The output voltage of the battery identification circuit 19 is, for example, 5V for Ni—Cd batteries and 0V for Ni—MH batteries. The control circuit 42 performs charge control by changing at least one of the battery protection temperature and a predetermined value according to the determination result, and also changes the driving mode of the fan 25.

  By comprising in this way, even if it can charge several types of secondary batteries with the same charger 31, it can determine a charge stop appropriately for each.

It is a block diagram which shows the electrical structure of the charger and secondary battery in the electric tool set which concerns on one Embodiment of this invention. It is a top view which shows the structure of the said charger. It is a bottom view which shows the structure of the said charger. It is a longitudinal cross-sectional view which shows the structure of the said charger. It is a flowchart for demonstrating operation | movement of the control circuit of the charger of this invention. It is a block diagram which shows the electrical structure of the charger and secondary battery in the electric tool set which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,31 Charger 2,32 Secondary battery 3 Commercial power supply 11 Charging current control circuit 12,42 Control circuit 13 Atmosphere temperature detection circuit 14 Atmosphere temperature high temperature abnormality display part 15 Battery temperature high temperature abnormality display part 16 Power supply circuit 17 Battery cell 18 Battery temperature detection circuit 19 Battery identification circuit 21 Insertion hole 22 Discharge port 23 Suction port 24 Duct 25 Fan 26 Display unit 29 Ventilation holes P1, P2 Charging terminal P3 Power supply terminal P4 Detection terminal P5 Identification terminal

Claims (5)

In response to the detection result of the battery temperature detection means built in the attached secondary battery to be charged, the control means controls the charging current control means when the detected temperature is equal to or higher than a predetermined first temperature, In a charger that prevents the supply of charging current to the secondary battery from being stopped or started,
An ambient temperature detection means for detecting the ambient ambient temperature;
Display means,
The control means is responsive to the detection result of the ambient temperature detection means, and causes the display means to display that the ambient temperature is high when the detected temperature is equal to or higher than a predetermined second temperature. Charger.   Even if the detection result of the battery temperature detection means is lower than the first temperature, the control means determines that the atmosphere temperature is equal to or higher than the first temperature from the detection result of the atmosphere temperature detection means, or the atmosphere When the difference between the temperature and the first temperature is within a predetermined value, the charging current control means is controlled so as not to stop or start the supply of the charging current to the secondary battery. The charger according to claim 1, wherein:   3. The charging according to claim 2, further comprising: a discriminating unit that discriminates a type of the secondary battery to be mounted and changes at least one of the first temperature or a predetermined value according to the discrimination result. vessel.   4. The atmosphere temperature detecting means is provided in the vicinity of a suction port for outside air for cooling or in an air path from the suction port to a discharge port for blowing out air for cooling a secondary battery. The charger according to claim 1.   The power tool set using the charger according to any one of claims 1 to 4.

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