JPWO2017002520A1 - Battery charger for power tool battery pack - Google Patents

Abstract

In order to provide a charging device capable of charging a high-capacity battery pack in a short time, the charging device can charge a battery pack including a secondary battery, and the battery pack having a nominal capacity of 5 Ah or more is charged to 2 C or more. It is configured to be rechargeable with current.

Description

The present invention relates to a charging device for charging a battery pack including a secondary battery such as a nickel / cadmium battery, a nickel / hydrogen battery, or a lithium ion battery.

Conventionally, a battery pack is used as a power source for an electric tool or the like, and the battery pack is charged by a dedicated charging device. Battery packs used for electric tools and the like have a large battery capacity and a high discharge voltage. In recent years, the capacity has further increased, and battery packs with a nominal capacity of 5 Ah or more have appeared.

On the other hand, a charging device described in Patent Document 1 is known as a charging device that charges a battery pack having a nominal capacity of less than 5 Ah with a charging current of a charging rate of 2C or more.

JP 2008-104349 A

However, in the charging device described in Patent Document 1, charging a battery pack having a high capacity (5 Ah or more) is not considered. In addition, in a configuration in which a high-capacity battery pack (5 Ah or more) is charged with a charging current comparable to that of a conventional battery pack (less than 5 Ah), it takes a long time to charge the high-capacity battery pack, and the charging time It was difficult to shorten. In addition, a configuration in which charging is performed with a relatively large charging current with respect to the nominal capacity of the high-capacity battery pack and the charging time is shortened is also conceivable. In this case, for the protection of the secondary battery provided in the battery pack. There is also a problem that the charging current is interrupted by the interrupting means (fuse, thermal protector, etc.), the charging is interrupted or terminated, and as a result, the charging time cannot be shortened.

Accordingly, an object of the present invention is to provide a charging device that can charge a high-capacity battery pack in a short time.

In order to solve the above problems, the present invention is a charging device capable of charging a battery pack including a secondary battery, and is configured to be able to charge the battery pack having a nominal capacity of 5 Ah or more with a charging current of 2 C or more. A charging device is provided.

According to such a configuration, a high-capacity battery pack with a nominal capacity of 5 Ah or more can be charged with a charging current of 2 C or more, so that a high-capacity battery pack can be charged in a short time of about 30 minutes. it can.

In order to solve the above problems, the present invention further provides a charging device capable of charging a battery pack including a secondary battery, wherein the battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more is 2αA. Provided is a charging device configured to be able to be charged with the above charging current.

According to such a configuration, a high-capacity battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more. A high-capacity battery pack can be charged.

In the above configuration, the battery pack further includes a blocking unit that allows a charging current to flow through the secondary battery when a predetermined condition is satisfied and blocks the charging current when the predetermined condition is not satisfied. A battery connection portion connectable to the battery pack, and a charge control means for specifying the predetermined condition of the blocking means of the battery pack connected to the battery connection section and performing charge control so as to satisfy the predetermined condition And preferably.

According to such a configuration, the charging control unit performs charging control so that the predetermined condition of the blocking unit is satisfied. Therefore, the charging current is not blocked by the blocking unit, and charging is not interrupted or terminated. For this reason, it is possible to charge a high-capacity battery pack with a relatively large charging current, and it is possible to charge the high-capacity battery pack in a short time.

In order to solve the above problems, the present invention further provides a secondary battery and a charging current that is allowed to flow through the secondary battery when a predetermined condition is satisfied and does not satisfy the predetermined condition. A charging device capable of charging a battery pack comprising: a battery connecting portion connectable to the battery pack; and the shutting means of the battery pack connected to the battery connecting portion. There is provided a charging device comprising: charge control means for specifying a predetermined condition and performing charge control so as to satisfy the predetermined condition.

According to such a configuration, the charging control unit performs charging control so that the predetermined condition of the blocking unit is satisfied. Therefore, the charging current is not blocked by the blocking unit, and charging is not interrupted or terminated. For this reason, it is possible to charge a high-capacity battery pack with a relatively large charging current, and it is possible to charge the high-capacity battery pack in a short time.

In the above configuration, it is preferable that the battery pack having a nominal capacity of 5 Ah or more can be charged with a charging current of 2 C or more.

According to such a configuration, a high-capacity battery pack with a nominal capacity of 5 Ah or more can be charged with a charging current of 2 C or more, so that a high-capacity battery pack can be charged in a short time of about 30 minutes. it can.

Further, it is preferable that the battery pack having a nominal capacity α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more.

According to such a configuration, a high-capacity battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more. A high-capacity battery pack can be charged.

The predetermined condition is satisfied when the charging current is smaller than an allowable maximum current value corresponding to the battery temperature of the secondary battery, and the charge control means acquires a battery temperature of the battery pack. Temperature acquisition means, current setting means capable of setting one current value from a plurality of current values, and current control means for controlling the charging current so as to charge the battery pack with the set one current value And charging the battery pack with a maximum current value among current values smaller than an allowable maximum current value among the plurality of settable current values based on the battery temperature. It is preferable to control the current.

According to such a configuration, the battery pack can be charged with the maximum current value among the current values smaller than the allowable maximum current value among the plurality of settable current values based on the battery temperature. That is, the battery pack can be charged with the maximum current value among the current values that satisfy the predetermined condition. For this reason, the charging time can be further shortened.

Further, it is preferable that the allowable maximum current value in the predetermined condition becomes smaller as the battery temperature becomes higher, and the charging control means makes the charging current smaller as the battery temperature becomes higher.

According to such a configuration, the charging current can be changed in accordance with a predetermined condition, that is, the interruption characteristic of the interruption means, so that interruption of the charging current by the interruption means can be reliably avoided. Thereby, charging time can be shortened reliably.

In addition, when charging with the first current value, the charging control means is configured to charge with a second current value smaller than the first current value when the battery temperature is equal to or higher than the first temperature threshold. Preferably, the one temperature threshold is lower than the first battery temperature at which the corresponding allowable maximum current value is the first current value.

According to such a configuration, the interruption of the charging current by the interruption means can be avoided more reliably. More specifically, the allowable maximum current value corresponding to the first battery temperature is the first current value, and when charging is performed with the first current value, when the battery temperature reaches the first battery temperature, the cutoff means Although the charging current is cut off, the above configuration changes the charging current from the first current value to a smaller second current value when the battery temperature reaches a first temperature threshold lower than the first battery temperature. Can be more reliably avoided.

Further, in the case where the charging control unit is charged with the second current value, a third value smaller than the second current value is obtained when the battery temperature becomes equal to or higher than a second temperature threshold value higher than the first temperature threshold value. The charging current is controlled to charge at a current value, and the second temperature threshold is lower than the second battery temperature at which the corresponding allowable maximum current value is the second current value, and the first battery temperature Higher than that.

According to such a configuration, it is possible to more reliably avoid the interruption of the charging current by the interruption means and further shorten the charging time. More specifically, since the second temperature threshold value for changing the charging current from the second current value to the smaller third current value is lower than the second battery temperature, it is possible to reliably avoid the operation of the cutoff means. it can. Further, the second temperature threshold is not a value higher than the first battery temperature, that is, an excessively low value. If the second temperature threshold is set to an excessively low value, for example, if the second temperature threshold is set to a value lower than the first battery temperature, it is possible to reliably avoid the operation of the cutoff means, but the charging current is set to the second value. The timing for changing from the current value to the smaller third current value is advanced, and the charging time cannot be sufficiently shortened. In this regard, by setting the second temperature threshold higher than the first battery temperature as in the above configuration, the timing for changing to a smaller current value can be delayed, and the charging time can be further shortened.

Moreover, it is preferable that this interruption | blocking means is a thermal protector.

Moreover, it is preferable that this interruption | blocking means is a fuse.

Further, it is preferable that a plurality of battery packs having different voltages and different nominal capacities can be selectively charged, and a battery pack having a nominal capacity of less than 5 Ah can be charged with a charging current of 2 C or more. .

According to such a configuration, a battery pack of less than 5 Ah can be rapidly charged.

In order to solve the above-mentioned problems, the present invention further provides a charging device capable of directly charging a battery pack including a secondary battery from a commercial AC power source, wherein the battery pack having a nominal capacity of 5 Ah or more is 2C or more and 3C or less. Provided is a charging device configured to be able to be charged with a charging current.

In order to solve the above-mentioned problem, the present invention further provides a charging device capable of directly charging a battery pack including a secondary battery from a commercial AC power source, wherein the nominal capacity is α (α is a real number of 5 or more) Ah or more. Provided is a charging device characterized in that the battery pack can be charged with a charging current of 2αA or more and 3αA or less.

According to the charging device of the present invention, a high-capacity battery pack can be charged in a short time.

1 is an external view of a charging device according to a first embodiment of the present invention. The top view of the charging device shown in FIG. The side view of the charging device shown in FIG. The top view which shows the charging circuit part in the case of the charging device shown in FIG. The side view of the charging device shown in FIG. 1 which charges a battery pack. The perspective view which shows the thermal radiation member, charging circuit part, 1st and 2nd fan inside the charging device shown in FIG. The front view of the charging device shown in FIG. 1 which charges a battery pack. It is a figure explaining the relationship between a heat radiating member and cooling air, (a) is the flow of cooling air when there is no second heat radiating part, (b) is the flow of cooling air when there is a second heat radiating part. To do. FIG. 2 is a circuit diagram including a block diagram illustrating an electrical configuration of the charging device illustrated in FIG. 1, and illustrates a state where a battery pack is mounted on a battery mounting portion. The figure which shows the 1st interruption | blocking characteristic curve which the 1st interruption | blocking element with which the battery pack shown in FIG. 9 is provided has. The figure which shows the 2nd interruption | blocking characteristic curve which the 2nd interruption | blocking element with which the battery pack shown in FIG. 9 is provided has. The flowchart which shows the charge process by the charge control part of the charging device shown in FIG. The flowchart which shows the charge process by the charge control part of the charging device shown in FIG. The table for determining the target electric current value used when the charge control part of the charging device shown in FIG. 9 charges a battery pack. (A) And (b) is a time chart which shows the time change of the battery temperature at the time of performing charge control by the charge control part of the charging device shown in FIG. 9, a charging voltage, and a charging current. (C) is a time chart which shows the time change of the battery temperature at the time of performing charge control by the conventional charging device, a charging voltage, and a charging current. The top view which shows the inside of the charging device which shows the modification of 1st Embodiment. The perspective view of the heat sink in the modification shown in FIG. The perspective view which shows the relationship between the heat sink shown in FIG. 16, and the air path defined. The figure explaining the flow of the cooling air in the charging device shown in FIG. 16 when charging a battery pack. The figure explaining the flow of the cooling air in the charging device shown in FIG. 16 when charging a battery pack. The top view which shows the charging circuit part in the case of the charging device by the 2nd Embodiment of this invention. The side view of the charging device shown in FIG. The top view which shows the modification of 2nd Embodiment. The top view which shows the modification of 2nd Embodiment. The side view which shows the modification of 2nd Embodiment. The side view which shows the modification of 2nd Embodiment. The top view which shows the modification of 2nd Embodiment. The top view which shows the modification of 2nd Embodiment. The top view of the charging device by the 3rd Embodiment of this invention. The flowchart which shows the 1st charging operation of the charging device by the 3rd Embodiment of this invention. The figure explaining the 1st cooling air which arises when only a 1st fan is driven in the charging device shown in FIG. The figure explaining the 2nd cooling air which arises when only the 2nd fan is driven in the charging device shown in FIG. The top view which shows the 1st and 2nd cooling air which arises in a case when the charging device shown in FIG. 29 charges a battery pack. The flowchart which shows the 2nd charging operation of the charging device by the 3rd Embodiment of this invention. FIG. 30 is a diagram for explaining cooling air flowing in the case when the rotation speed of the first fan is larger than the rotation speed of the second fan in the charging device shown in FIG. 29. FIG. 30 is a diagram for explaining cooling air generated in the case when the rotation speed of the second fan is larger than the rotation speed of the first fan in the charging device shown in FIG. 29. Side surface sectional drawing which shows the inside of the charging device by the 4th Embodiment of this invention. The top view of the charging device shown in FIG. The top view of the charging device by the 5th Embodiment of this invention.

A charging apparatus according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the direction in which the surface on which the battery pack is attached to the charging device faces is defined as the upward direction, and the opposite direction is defined as the downward direction. Further, the left-right direction and the front-rear direction are the directions shown in the drawings unless otherwise specified.

The charging device 1 according to the first embodiment of the present invention charges a plurality of types of battery packs including the battery packs 3 and 33, that is, a plurality of battery packs having different battery types (battery pack voltage and nominal capacity). It is configured to be possible. In the following description, the case where the battery pack 3 is attached to the charging device 1 will be mainly described, and the battery pack 33 will be described together with the description of the battery pack 3 as appropriate.

Referring to FIGS. 1 to 5, the charging device 1 includes a case 2 with a charging circuit unit 4 for charging the battery pack 3 and a plurality of fans for cooling the charging circuit unit 4 and the battery pack 3. The first fan 5 and the second fan 6 are provided.

The case 2 has a substantially rectangular parallelepiped shape, and a battery mounting portion 7 on which the battery pack 3 is mounted for charging is provided on the upper surface 21 on the front side. The battery mounting portion 7 is provided with a plurality of terminals 70 for charging the battery pack 3 and an opening 71 through which wind for cooling the battery pack 3 passes. Furthermore, the case 2 has four side surfaces 22, 23, 24, and 25 that surround the upper surface 21, and a bottom surface 27 that is located on the opposite side of the upper surface 21, and the side surfaces 22 and 23 that are adjacent to each other are at the corners 26. Are connected. Further, the side surfaces 22 and 24 face each other, and the side surfaces 23 and 25 face each other. In the case 2, the direction from the bottom surface 27 toward the upper surface 21 is defined as the upper direction of the charging device 1, that is, the first direction intersecting with the upper surface.

As shown in FIG. 4, the first fan 5 is disposed in the case 2 in the vicinity of the corner portion 26 and the opening 71 and in the vicinity of the side surface 22. The first fan 5 has a first rotating shaft 5a. Moreover, the 1st exhaust port 22a which consists of a some ventilation window is formed in the part of the side surface 22 which the 1st fan 5 opposes. When driven, the first fan 5 generates first cooling air in the direction of the first rotating shaft 5a. The first cooling air flows toward the first exhaust port 22a and is exhausted from the case 2 through the first exhaust port 22a.

As shown in FIG. 4, the second fan 6 is disposed in the case 2 in the vicinity of the corner portion 26 and the opening 71 and in the vicinity of the side surface 23. The second fan 6 has a second rotating shaft 6a. The second fan 6 is arranged such that the extending direction of the second rotating shaft 6 a intersects the extending direction of the first rotating shaft 5 a of the first fan 5. A second exhaust port 23 a made up of a plurality of ventilation windows is formed in the portion of the side surface 23 that faces the second fan 6. When driven, the second fan 6 generates second cooling air in the direction of the second rotation shaft 6a. The second cooling air flows toward the second exhaust port 23a and is exhausted from the case 2 through the second exhaust port 23a. Therefore, the cooling efficiency of the heating element in the charging device 1 can be increased by the plurality of fans (the first fan 5 and the second fan 6). Furthermore, by arranging the fans 5 and 6 along the side surfaces of the case 2 (specifically, the side surfaces 22 and 23), it is possible to secure an installation space in the case 2 of the substrate 40 and to effectively use the substrate 40. . In particular, it is effective to provide in the vicinity of the corner portion connecting the side surfaces of the case 2.

In the case 2, a plurality of ventilation windows are formed as intake ports 24 a over a predetermined range on the side surface 24 opposite to the side surface 22. Therefore, when the first fan 5 and the second fan 6 are driven, air is taken into the case 2 from the intake port 24a, and the taken air passes through the inside of the case 2 as first and second cooling air. It passes along the cooling air passage and is exhausted to the outside of the case 2 through the first and second exhaust ports 22a and 23a. Details of the cooling air passage will be described later.

The charging circuit unit 4 includes a diode 40, a transformer 42, an FET 43, a temperature detection element 44, and a charging control unit 45 on a substrate 40 disposed in the vicinity of the air inlet 24a in the case 2. Implemented and configured. The charging circuit unit 4 charges the battery pack 3 through the terminal 70 using, for example, power supplied from the commercial AC power supply P under the control of the charging control unit 45. When a large amount of current per unit time is passed through the charging circuit unit 4 for large current and rapid charging, so-called 2C charging, the diode 41, the transformer 42, and the FET 43 tend to generate heat. In order to protect these components from heat generation and promote heat dissipation, heat dissipation members 46 and 47 are attached to the diode 41 and the FET 43, respectively.

Further, the diode 41, the transformer 42, and the FET 43 are disposed in the vicinity of the air inlet 24a so as to be directly exposed to the air introduced into the case 2 from the air inlet 24a. In particular, the transformer 42 is arranged on the most upstream side of the cooling air passage, that is, in the vicinity of the intake port 24a.

The heat dissipating member 46 is formed of a metal having high thermal conductivity, and as shown in FIG. 5, a plate-shaped first heat dissipating from the substrate 40 toward the upper surface 21, that is, in the first direction, to which the diode 41 is fixed. Part 46A, and a plate-like second heat radiating part 46B extending from the tip of the first heat radiating part 46A to the heat radiating member 47 substantially parallel to the upper surface 21. The direction in which the second heat radiating portion 46B extends is the direction intersecting the first direction, that is, the second direction. Therefore, the heat radiating member 46 has a substantially L-shaped cross section when viewed from the side.

Similarly, the heat radiating member 47 is formed of a metal having high thermal conductivity, and as shown in FIG. 5, extends in the first direction from the substrate 40 toward the upper surface 21 and the plate-like first heat radiating to which the FET 43 is fixed. 47A, and a plate-like second heat radiating portion 47B extending in the second direction toward the heat radiating member 46 from the front end of the first heat radiating portion 47A substantially parallel to the upper surface 21. Therefore, the heat radiating member 47 has a substantially L-shaped cross section when viewed from the side.

As shown in FIG. 6, when the heat radiating members 46 and 47 are mounted on the substrate 40, one end portions of the first heat radiating portion 46 </ b> A and the first heat radiating portion 47 </ b> A are separated from each other and in the vicinity of the air inlet 24 a. Placed in. Further, the second heat radiating portions 46B and 47B are arranged at a predetermined distance determined by the standard from the transformer 42 so as to sandwich the transformer 42 therebetween. Further, as shown in FIG. 5, the second heat radiating portion 46 </ b> B and the second heat radiating portion 47 </ b> B are located between the diode 41 and the FET 43 and the upper surface 21 in the first direction. The first and second heat radiating portions 46A and 46B of the heat radiating member 46 and the first and second heat radiating portions 47A and 47B of the heat radiating member 47 are formed to have dimensions that allow an appropriate insulation distance from the transformer 42. ing.

Further, when the heat radiating members 46 and 47 are mounted on the board 40, together with the board 40, the air passage of the air taken into the case 2 from the intake port 24 a is defined, and the diode 41 is placed in the air path. , The transformer 42, and the FET 43.

The temperature detection element 44 is made of, for example, a thermistor, and detects the temperature inside the case 2.

The charging control unit 45 controls the charging of the battery pack 3 by the charging circuit unit 4 while monitoring the temperature of the battery pack 3 and controls the rotation of the first and second fans 5 and 6.

In the charging device 1, when the battery pack 3 is attached to the battery mounting portion 7 as shown in FIG. 7, the first fan 5 and the second fan 6 are driven. By driving the fan, first cooling air and second cooling air are generated in the case 2 to form a cooling air passage from the intake port 24a to the first exhaust port 22a and the second exhaust port 23a.

In the vicinity of the air inlet 24a, the cooling air path is formed on the upper surface of the heat radiating members 46A, 47A and the second heat radiating parts 46B, 47B and the substrate 40 as shown in FIG. The part is defined as a duct having an opening. Accordingly, the first cooling air and the second cooling air flow from the one end side near the intake port 24a of each of the first heat radiating portions 46A and 47A toward the other end side near the exhaust ports 22a and 23a. Proceed inside.

The cooling air generally tends to pass through the shortest distance from the intake port 24a toward the exhaust ports 22a and 23a. For this reason, when the second heat radiating portion 46B is not provided, most of the cooling air does not flow from one end portion of the heat radiating member 46 to the other end portion as shown in FIG. And reach the exhaust ports 22a and 23a directly. Therefore, the first cooling air or the second cooling air does not pass through the diode 41, the transformer 42, and the FET 43 disposed between the heat radiation members 46, 47, and the diode 41, the transformer 42, and the FET 43 are sufficiently cooled. It will not be possible.

On the other hand, in the embodiment of the present invention, as shown in FIG. 8A, the cooling air is cooled by the second heat radiating portions 46B and 47B extending in the second direction from the respective tip portions of the first heat radiating portions 46A and 47A. However, it is blocked | prevented from flowing through the 1st thermal radiation part 46A to the exhaust ports 22a and 23a. For this reason, the cooling air flows from one end portion of each of the first heat radiating portions 46A and 47A toward the other end portion, so that the diode 41, the transformer 42, and the FET 43 disposed between the heat radiating members 46 and 47 are adjacent to each other. The diode 41, the transformer 42, and the FET 43 can be sufficiently cooled.

The arrangement of the diode 41, the transformer 42, and the FET 43 in the cooling air path defined by the heat dissipating members 46 and 47 shown in FIGS. 4, 5, and 6 is an example, and the first cooling air and the second cooling air are used. If it passes by the side of an element, it can take an appropriate arrangement. Further, the cooling air is supplied to the inside of the case 2 by the fans 5 and 6 using the exhaust ports 22a and 23a provided close to the first fan 5 and the second fan 6 as the intake ports and the intake port 24a as the exhaust ports. It is good also as a structure incorporated in. However, in this case, since the cooling air is blown to the heat generating element, the cooling effect is lower than the structure in which the first fan 5 and the second fan 6 discharge the air outside the case 2. Since the cooling air is focused near the opening 24a (used as an exhaust opening), the heat generating elements (such as the transformer 42) disposed in the vicinity of the intake opening 24a can be cooled with a high air volume. Moreover, dust may be sucked together with air by the first fan 5 and the second fan 6 and may be clogged in the exhaust ports (22a, 23a). Therefore, by adopting a configuration in which the first fan 5 and the second fan 6 discharge the air outside the case 2, the cooling efficiency of the heating element can be increased and clogging of the exhaust ports (22a, 23a) is suppressed. can do.

Moreover, in order to cool the battery pack 3, an air path is also formed between the opening 71 and the first exhaust port 22a and the second exhaust port 23a by the duct 90 shown in FIG. The duct 90 separates the cooling air path of the battery pack 3 and the cooling air path of the charging device 1. That is, the air taken into the battery pack 3 from the air inlet of the battery pack 3 and taken into the charging device 1 through the opening 71 passes through the upper side of the duct 90 from the first exhaust port 22a and the second exhaust port 23a. Discharged. On the other hand, the air taken into the charging device 1 from the intake port 24a passes through the lower side of the duct 90 without flowing to the battery pack 3 side through the duct 90 and is discharged from the first exhaust port 22a and the second exhaust port 23a. Note that the duct 90 is omitted in FIG.

Here, the electrical configuration of the battery pack 3 and 33 connected to the charging device 1 and the charging device 1 according to the first embodiment will be described with reference to FIG. 9. The battery pack 3 and the battery pack 33 are different from each other in battery type and have different cutoff elements, allowable charging current values and internal resistance (nominal capacity) of the battery set, etc., but the basic configuration, the connection relationship with the charging device, and the charging device The communication method with 1 is the same. For this reason, the battery pack 3 will be described as an example, and only the differences with respect to the battery pack 33 will be described. FIG. 9 is a circuit diagram including a block diagram showing an electrical configuration of the charging device 1 and the battery packs 3 and 33, and shows a state where the battery pack 3 or 33 is attached to the battery attachment portion 7.

First, the electrical configuration of the battery pack 3 will be described. The battery pack 3 is a battery pack having a high capacity (nominal capacity of 5 Ah or more) that is configured to be detachable from a power tool such as a hammer drill or a portable circular saw and used as a power source for driving the power tool. As shown in FIG. 9, the battery pack 3 includes a battery set 3A, a connection terminal portion 3B, a protection IC 3C, a battery-side power supply circuit 3D, a battery temperature detection circuit 3E, a first cutoff element 3F, A battery-side control unit 3G. The battery capacity may be a rated capacity.

The battery set 3A has a configuration in which four battery cells 3a are connected in series. In the present embodiment, for example, the battery cell 3a is a lithium ion battery, the nominal voltage is 3.6V, the maximum charging voltage is 4.2V, and the maximum charging voltage as the battery set 3A is 16.8V (4. 2V / cell × 4 cells). Further, the battery pack 3A has a nominal capacity of 6Ah and an allowable charging current value of about 12A (or 2C), and has a high capacity as a driving power source for the electric tool. The allowable charging current value is the maximum value of the charging current that can be charged without the risk of deterioration or failure of the battery set 3A, and 12A (2C) is merely an example and may be more than that. For example, in the case of a high-performance battery cell, an allowable charging current value of 12 A (2C) or more may be used. The battery cell 3a is an example of the “secondary battery” in the present invention.

The connection terminal portion 3B has a positive connection terminal 3b and a negative connection terminal 3c. The positive connection terminal 3b is connected to the positive terminal of the battery cell 3a having the highest potential via the first cutoff element 3F. The minus connection terminal 3c is connected to the minus terminal of the battery cell 3a having the lowest potential. When the battery pack 3 is mounted on the battery mounting portion 7 of the charging device 1, each of the positive connection terminal 3 b and the negative connection terminal 3 c is connected to a predetermined terminal among the plurality of terminals 70 of the charging device 1. The set 3A and the charging device 1 are connected. The battery mounting part 7 and the terminal 70 are examples of the “battery connection part” in the present invention.

The protection IC 3C individually monitors the voltage of each of the four battery cells 3a, and even if one of the cells is in a state that is not in a normal state, such as an overcharge state or an overdischarge state, an abnormal signal is sent to the battery. To the side control unit 3G. The battery side power supply circuit 3D is a circuit that transforms the voltage of the battery set 3A and supplies the electric power to the battery side control unit 3G.

The battery temperature detection circuit 3E is a circuit that detects the temperature (battery temperature) of the battery set 3A, and includes a temperature sensitive element such as a thermistor (not shown) provided adjacent to the battery set 3A. The battery temperature detection circuit 3E detects a battery temperature using a temperature sensitive element such as a thermistor, converts the detected temperature into a voltage signal, and outputs the voltage signal to the battery side control unit 3G.

The first cutoff element 3F is, for example, a thermal protector, a fuse, or the like provided between the positive connection terminal 3b and the battery set 3A for protecting the battery set 3A (battery cell 3a). The first cutoff element 3F has a cutoff characteristic that defines a condition for cutting off the charging current. When the cutoff characteristic is satisfied, the first cutoff element 3F allows the charging current to flow through the battery set 3A (battery cell 3a). The charging current is cut off when the cutoff characteristic is not satisfied. More specifically, the first cutoff element 3F has a first cutoff characteristic curve A (charging current-ambient temperature curve) shown in FIG. The first blocking element 3F is an example of the “blocking unit” in the present invention.

FIG. 10 is a diagram illustrating a first cutoff characteristic curve A included in the first cutoff element 3F. The first interruption characteristic curve A is a curve showing a boundary between a state where the first interruption element 3F is in an open state and the charging current is interrupted and a state where the first interruption element 3F is in a closed state and the charging current is allowed. In the graph, the region above the first cutoff characteristic curve A is a region where the first cutoff element 3F is opened and cuts off the charging current, that is, a region that does not satisfy the cutoff characteristic. The ambient temperatures Ta to Te and T1 to T6 shown in FIG. 10 satisfy T1 <Ta <T2 <Tb <T3 <Tc <T4 <Td <T5 <Te <T6, and the charging currents I1 to I5 satisfies I5 <I4 <I3 <I2 <I1.

The first cutoff characteristic curve A of the first cutoff element 3F decreases as the charging current increases, and the maximum allowable ambient temperature (allowable maximum temperature) decreases, in other words, as the ambient temperature increases. The maximum charging current (allowable maximum current value) is set to be small.

For example, when the charging current is I4, the allowable maximum temperature is Td, and the charging current is allowed to flow until the ambient temperature reaches Td, and when the ambient temperature becomes equal to or higher than Td, the charging current is cut off. In other words, when the charging current is I4, the maximum allowable temperature is Td, and the cutoff characteristic is satisfied until the ambient temperature reaches Td, and when the ambient temperature exceeds Td, the cutoff characteristic is not satisfied. Become. In addition, when the interruption | blocking characteristic in this Embodiment is satisfy | filled, it is an example of "when the predetermined condition is satisfy | filled" in this invention.

On the other hand, when the charging current is I3 larger than I4, the allowable maximum temperature is Tc lower than Td in the case of the charging current I4, and when the ambient temperature is equal to or higher than Tc, the charging current is cut off. From another viewpoint, when the ambient temperature is Tc, the allowable maximum current value is I3, and when the charging current becomes I3 or more, the charging current is cut off. On the other hand, when the ambient temperature becomes Td higher than Tc, the allowable maximum current value becomes I4 smaller than I3.

Note that T6 is the ambient temperature at which the first cutoff element 3F is opened even when no charging current is flowing. In the present embodiment, the first cutoff element 3F is installed in contact with the battery set 3A, and the ambient temperature is substantially the same as the battery temperature. For this reason, the 1st interruption | blocking element 3F has not only the role which restrict | limits or interrupt | blocks a charging current but the role which prevents a charge start, when battery temperature is higher than predetermined value.

The battery side control unit 3G is a microcomputer having a ROM, a RAM, an arithmetic function, and the like, and includes an information communication port 3H. The information communication port 3 </ b> H is connected to a predetermined terminal among the plurality of terminals 70 of the charging device 1 when the battery pack 3 is connected to the charging device 1. Communication between the battery side control unit 3G and the charging device 1 is performed via the information communication port 3H.

The battery side control unit 3G transmits the battery type from the information communication port 3H to the charging device 1 during charging. The battery type is a classification based on the characteristics of the battery pack 3, and the charging device 1 can specify the characteristics of the battery pack 3 necessary for charge control by receiving the battery type from the battery-side control unit 3G. . The characteristics of the battery pack 3 that can be specified from the battery type include, for example, the number of battery cells 3a constituting the battery set 3A, the connection configuration (the number of series, the number of parallel), the maximum charging voltage of the battery cell 3a, and the battery set 3A. Nominal capacity of the battery pack 3, the cutoff characteristic (first cutoff characteristic curve A) of the first cutoff element 3F of the battery pack 3, the target charging voltage for properly charging the entire battery set 3A (in this embodiment, the maximum charging voltage) ), An allowable charging current value, a termination current value serving as a determination criterion for terminating charging, and the like. In the present embodiment, the battery type of the battery pack 3 is C, for example. Further, when an abnormal signal is input from the protection IC 3C, the battery side control unit 3G outputs a charge stop signal to the charging device 1 via the information communication port 3H.

Next, a battery pack 33 having a different battery type from the battery pack 3 will be described. The battery pack 33 includes a battery set 33A having characteristics different from those of the battery set 3A. The battery set 33A has the same nominal capacity (6Ah) as the battery set 3A, but the allowable charging current value is different, for example, 12A (2C) or more. Since the allowable charging current value varies depending on the manufacturer and performance of the battery cell, it is not limited to this current value. Since the battery pack 33 includes the battery set 33A having an allowable charging current value different from that of the battery set 3A, the battery pack 33 includes the second cutoff element 33F having a cutoff characteristic different from that of the first cutoff element 3F. More specifically, the second cutoff element 33F has a second cutoff characteristic curve B shown in FIG. In the present embodiment, the battery type of the battery pack 33 is, for example, D. When the battery pack 33 is attached, the charging device 1 receives D as the battery type from the battery side control unit 3G of the battery pack 33. Is received, the cutoff characteristic of the second cutoff element 33F of the battery pack 33, that is, the second cutoff characteristic curve B, the target charging voltage, and the like can be specified. The second blocking element 33F is an example of the “blocking unit” in the present invention.

FIG. 11 is a diagram illustrating a second cutoff characteristic curve B included in the second cutoff element 33F. Note that the ambient temperatures T1 to T5 and the charging currents I1 to I5 shown in FIG. 11 are the same values as the ambient temperatures T1 to T5 and the charging currents I1 to I5 shown in FIG. , T6 and Tf to j satisfy T5 <Tf <Tg <Th <Ti <Tj <T6.

As shown in FIG. 11, in the second cutoff characteristic curve B of the second cutoff element 33F, the allowable maximum temperature decreases as the charging current increases, similarly to the first cutoff characteristic curve A of FIG. Yes. In the second cutoff element 33F (second cutoff characteristic curve B), the allowable maximum temperatures corresponding to the charging currents I1 to I5 are Tf to Tj, respectively, and Tf is the lowest allowable maximum temperature of Tf to Tj. Even if it exists, it is higher than allowable maximum temperature Ta-Te corresponding to each of charging current I1-I5 in T5 and the 1st interruption | blocking element 3F (1st interruption | blocking characteristic curve A).

In the present embodiment, as described above, the battery temperature is substantially the same as the ambient temperature, and generally the battery temperature tends to increase as the charging current increases and the charging current flows for a longer time. . In view of the above, the battery pack 33 including the second cutoff element 33F having a higher allowable maximum temperature than the first cutoff element 3F of the battery pack 3 causes a larger charging current to flow for a longer time than the battery pack 3. be able to. For example, when battery pack 3 and battery pack 33 are charged with charging current I1, battery temperature (ambient temperature) is only allowed up to Ta (<Tf) in battery pack 3, but Tf is lower in battery pack 33. (> Ta) is allowed. For this reason, when the ambient temperature Ta is reached, the charging current (I1) is cut off in the battery pack 3, but is not cut off in the battery pack 33, and the charging current can flow after that. Thus, in the battery pack 33, the charging current I1 can flow for a longer time than the battery pack 3.

Next, the electrical configuration of the charging device 1 will be described. As shown in FIG. 9, the charging device 1 includes a power supply circuit 48, an auxiliary power supply circuit 53, a switching power supply circuit 54, a charge control unit 45, a voltage setting control circuit 55, and a current setting circuit 56. A current control circuit 57, a first control signal transmission unit 61, a second control signal transmission unit 62, a fan unit 58, a temperature detection element 44, a voltage detection circuit 59, and a display circuit 60. In the state where the battery pack 3 is mounted, the battery set 3A (battery cell 3a) of the battery pack 3 is charged by constant current and constant voltage control.

The constant current / constant voltage control means setting a target current value when charging is started, charging while controlling the charging current so that the charging current becomes the target current value (constant current control), and charging the entire battery set 3A. After the voltage reaches the predetermined target charging voltage, charging is continued while keeping the charging voltage at the target charging voltage (constant voltage control), and the charging current becomes below the predetermined end current value under constant voltage control. In this case, charging control is performed to end charging.

The power supply circuit 48 is a circuit that supplies power to the battery pack 3, and includes a first rectifying / smoothing circuit 50, a switching circuit 51, a charging plus line 48 </ b> A, a charging minus line 48 </ b> B, and a second rectifying / smoothing circuit 52. It has.

The first rectifying / smoothing circuit 50 includes a full-wave rectifying circuit 50A and a smoothing capacitor 50B, and full-wave rectifies the AC voltage supplied from the commercial AC power supply P by the full-wave rectifying circuit 50A, thereby smoothing the capacitor 50B. Smoothes and outputs a DC voltage. The commercial AC power source P is, for example, an AC 100V external power source or the like.

The switching circuit 51 is connected to the first rectifying / smoothing circuit 50, and includes a transformer 42, an FET 43, and a PWM control IC 51A. The PWM control IC 51A changes the drive pulse width of the FET 43, and the FET 43 performs switching according to the drive pulse width, and uses the DC output from the first rectifying and smoothing circuit 50 as the voltage of the pulse train waveform. The voltage of the pulse train waveform is applied to the primary winding of the transformer 42, and is stepped down (or stepped up) by the transformer 42 and output to the second rectifying and smoothing circuit 52.

The second rectifying / smoothing circuit 52 includes two diodes 41, a smoothing capacitor 52A, and a discharging resistor 52B. The output voltage obtained from the secondary winding of the transformer 42 is rectified and smoothed to output a DC voltage. The DC voltage is configured to be output from predetermined terminals (a plurality of terminals 70) connected to the positive connection terminal 3b and the negative connection terminal 3c of the battery pack 3, respectively.

The charging plus line 48 </ b> A and the charging minus line 48 </ b> B are electric paths through which a charging current flows when the battery pack 3 is charged. The charging plus line 48 </ b> A connects the terminal 70 connected to the plus connection terminal 3 b and one end of the secondary winding of the transformer 42 in a state where the battery pack 3 is connected to the battery mounting portion 7. The charge minus line 48B connects the terminal 70 connected to the minus connection terminal 3c and the other end of the secondary winding of the transformer 42 in a state where the battery pack 3 is connected to the battery mounting portion 7. A current detection resistor 48C is provided on the charge minus line 48B.

The current detection resistor 48C is a shunt resistor for detecting a charging current flowing through the battery pack 3, and is provided between the second rectifying / smoothing circuit 52 and GND on the charging minus line 48B. The charge current is detected by inverting and amplifying the voltage drop of the current detection resistor 48C by the current control circuit 57 and inputting it to the charge control unit 45.

The auxiliary power supply circuit 53 is a constant voltage power supply circuit for supplying a stabilized reference voltage Vcc to various circuits such as the charging control unit 45 and operational amplifiers 55E and 57A described later. The auxiliary power supply circuit 53 is connected to the first rectifying / smoothing circuit 50, and includes coils 53a, 53b and 53c, a switching element 53A, a control element 53B, a rectifying diode 53C, a three-terminal regulator 53D, and an oscillation preventive circuit. Capacitors 53E and 53F and a reset IC 53G are provided. The reset IC 53G is an IC that outputs a reset signal to the charge control unit 45 to reset the charge control unit 45.

The switching power supply circuit 54 is a circuit that supplies power to the PWM control IC 51A, and includes a coil 54a, a rectifier diode 54b, and a smoothing capacitor 54c.

The charge control unit 45 is a microcomputer including a ROM, a RAM, and a calculation unit, and includes an A / D input port unit 45A, a first output port unit 45B, a second output port unit 45C, and a digital communication port unit 45D. And a reset port unit 45E. The charging control unit 45 processes various signals input to the A / D input port unit 45A and the digital communication port unit 45D by the calculation unit, and outputs various signals based on the processing result to the first output port unit 45B and the second output. Output from the port unit 45C and the digital communication port unit 45D to the current setting circuit 56, the fan unit 58 and the like to control charging of the battery pack to be charged.

In the ROM, various control programs necessary for charge control, battery types of a plurality of types of battery packs that can be charged, characteristics corresponding to the battery types (the above-described cutoff characteristics, target charging voltage, etc.), shown in FIG. Stored table is stored. The charge control unit 45 receives the battery type from the battery pack connected to the terminal 70, and specifies the characteristics of the connected battery pack from the received battery type.

The A / D input port unit 45 </ b> A is connected to the current control circuit 57, the temperature detection element 44, and the voltage detection circuit 59. The A / D input port unit 45A has a voltage signal indicating the charging current from the current control circuit 57, a voltage signal indicating the temperature of the charging circuit unit 4 from the temperature detecting element 44, and a voltage indicating the charging voltage from the voltage detecting circuit 59. A signal is input.

The first output port unit 45B has a plurality of ports, and each of the plurality of ports is connected to the current setting circuit 56 or the fan unit 58. The charge control unit 45 sends a signal for setting a target current value from the first output port unit 45B to the current setting circuit 56 and a fan control signal for controlling the first fan 5 and the second fan 6 to the fan unit 58. Output to.

The second output port unit 45C has a plurality of ports, and each of the plurality of ports is connected to the display circuit 60 or the second control signal transmission unit 62. The charging control unit 45 outputs a signal for controlling the display circuit from the second output port unit 45 </ b> C to the display circuit 60 and a signal for controlling charging start / stop to the second control signal transmission unit 62.

The digital communication port unit 45D is connected to the information communication port 3H of the battery pack 3 when the battery pack 3 is connected to the battery mounting unit 7, and is configured to be capable of bidirectional communication. The charge control unit 45 acquires information on the battery pack 3 necessary for charge control, that is, the battery temperature and the battery type, through the digital communication port unit 45D. The reset port unit 45E is connected to the auxiliary power circuit 53 and receives a reset signal output from the reset IC 53G. The digital communication port unit 45D is an example of the “battery temperature acquisition unit” in the present invention.

The voltage setting control circuit 55 is a circuit that sets a target charging voltage and controls the charging voltage to become the target charging voltage. The voltage setting control circuit 55 includes voltage dividing resistors 55A to 55D, an operational amplifier 55E, and a diode 55F.

The voltage dividing resistors 55A and 55B are connected in series between the charging plus line 48A and GND, and the connection point of the voltage dividing resistors 55A and 55B is connected to the inverting input terminal of the operational amplifier 55E. The charging voltage appearing on the charging plus line 48A is divided by the voltage dividing resistors 55A and 55B, and the divided value is output to the inverting input terminal of the operational amplifier 55E as a comparison voltage value.

The voltage dividing resistors 55C and 55D are connected in series between the reference voltage Vcc and GND, and the connection point of the voltage dividing resistors 55C and 55D is connected to the non-inverting input terminal of the operational amplifier 55E. The reference voltage Vcc is divided by the voltage dividing resistors 55C and 55D, and the divided value is output to the non-inverting input terminal of the operational amplifier 55E as a reference value for setting the target charging voltage.

The operational amplifier 55E is an element that compares the above-described comparison voltage value with a reference value, and an output terminal thereof is connected to the first control signal transmission unit 61 via a diode 55F.

The current setting circuit 56 is a circuit that selectively sets a target current value, and includes voltage dividing resistors 56A to 56F. The voltage dividing resistors 56A and 56B are connected in series between the reference voltage Vcc and GND, and the voltage dividing resistors 56C to 56F are connected to the connection point 56a of the voltage dividing resistors 56A and 56B and the first of the charge control unit 45. The output port unit 45B is connected in parallel. The connection point 56a is connected to the current control circuit 57, and the voltage (divided voltage value) appearing at the connection point 56a is output to the current control circuit 57 as a reference value for setting the target current value. In the present embodiment, by outputting or not outputting a low signal from the first output port unit 45B to the voltage dividing resistors 56C to 56F, the target current value is selectively selected from five types of current values I1 to I5. Can be set to The current setting circuit 56 is an example of the “current setting means” in the present invention.

Specifically, the divided voltage value that appears at the connection point 56a when the low voltage is not output from any port of the first output port section 45B and the reference voltage Vcc is divided by the voltage dividing resistors 56A and 56B is the target value. This is a reference value when the current value is set to I1. In the present embodiment, I1 is, for example, 12A.

Further, when a low signal is output from the port connected to the voltage dividing resistor 56C of the first output port section 45B, and the reference voltage Vcc is divided by the parallel resistance of the voltage dividing resistors 56B and 56C and the voltage dividing resistor 56A The divided voltage value appearing at the connection point 56a becomes a reference value when the target current value is set to I2. In the present embodiment, I2 is, for example, 10A.

Similarly, the divided value that appears at the connection point 56a when a low signal is output from the port connected to the voltage dividing resistor 56D of the first output port portion 45B is a reference value when the target current value is set to I3. Thus, the divided voltage value that appears at the connection point 56a when a low signal is output from the port connected to the voltage dividing resistor 56E of the first output port section 45B is a reference value when the target current value is set to I4. When the low signal is output from the port connected to the voltage dividing resistor 56F of the first output port section 45B, the divided voltage value that appears at the connection point 56a is a reference value when the target current value is set to I5. . In the present embodiment, for example, I3 is 9A, I4 is 8A, and I5 is 6A.

Note that I1 to I5 set as target current values may be configured so that different values are set depending on the battery type (nominal voltage, number of cells, etc.) of the battery pack 3. In other words, if the types of battery packs (battery types) are different, the combinations of I1, I2, I3, I4, and I5 may be different. Further, a low signal may be output simultaneously from two or more of the four ports of the first output port section 45B connected to the voltage dividing resistors 56C to 56F. In this case, the target current value As a result, it is possible to set six or more types.

The current control circuit 57 includes operational amplifiers 57A and 57B, resistors 57C to 57G, and a diode 57H. The output terminal of the operational amplifier 57A is connected to the A / D input port unit 45A of the charge control unit 45, the inverting input terminal is connected to the current detection resistor 48C via the resistor 57C, and the non-inverting input terminal is connected to GND. Has been. The output terminal of the operational amplifier 57B is connected to the first control signal transmission unit 61 via the resistor 57G and the diode 57H, the inverting input terminal is connected to the output terminal of the operational amplifier 57A via the resistor 57E, and the non-inverting input terminal is The current setting circuit 56 is connected to a connection point 56a.

The current control circuit 57 inverts and amplifies the comparison voltage corresponding to the charging current input to the inverting input terminal of the operational amplifier 57A by the operational amplifier 57A and inputs the comparison voltage to the inverting input terminal of the operational amplifier 57B. 56 is compared with a reference value corresponding to the target current value input to the non-inverting input terminal of the operational amplifier 57B from 56, and a voltage signal corresponding to the comparison result is output from the output terminal of the operational amplifier 57B to control the charging current. . The current control circuit 57 is an example of the “current control unit” in the present invention. The charging control unit 45, the current setting circuit 56, and the current control circuit 57 are examples of the “charging control unit” in the present invention.

The first control signal transmission unit 61 includes a photocoupler 61A. The photocoupler 61A is connected to the voltage setting control circuit 55 and the current control circuit 57, and corresponds to signals output from the output terminal of the operational amplifier 55E of the voltage setting control circuit 55 and the output terminal of the operational amplifier 57B of the current control circuit 57. The feedback signal is output to the PWM control IC 51A.

The fan unit 58 includes a first fan 5, a second fan 6, a constant voltage circuit 58A, a first fan control circuit 5A, and a second fan control circuit 6A. The constant voltage circuit 58 </ b> A is a circuit that converts the output voltage of the second rectifying / smoothing circuit 52 and supplies the converted voltage to the first fan 5 and the second fan 6. The first fan control circuit 5 </ b> A and the second fan control circuit 6 </ b> A are connected to the first output port unit 45 </ b> B of the charging control unit 45. In response to the fan control signal output from the first output port section 45B, the first fan control circuit 5A controls the drive / stop of the first fan 5 and the air volume, and the second fan control circuit 6A includes the second fan. 6 drive / stop and control air volume.

The temperature detection element 44 is connected to the A / D input port unit 45A of the charge control unit 45, detects the temperature inside the case 2, that is, the temperature of the charging circuit unit 4, and a voltage indicating the detected temperature. The signal is output to the A / D input port unit 45A.

The voltage detection circuit 59 is a circuit that detects a charging voltage, and includes voltage dividing resistors 59A and 59B. The voltage dividing resistors 59A and 59B are connected in series between the charging plus line 48A and GND of the charging device 1, and the connection point of the voltage dividing resistors 59A and 59B is an A / D input port of the charging control unit 45. Connected to the unit 45A. The charging voltage appearing on the charging plus line 48A is divided by the voltage dividing resistors 59A and 59B, and the divided value is input to the A / D input port unit 45A of the charging control unit 45 as a voltage signal indicating the charging voltage. The charging control unit 45 detects the charging voltage by reading the voltage signal.

The display circuit 60 is a circuit for displaying the state of charge, and includes an LED 60A and resistors 60B and 60C. The LED 60A is connected to the second output port unit 45C of the charging control unit 45 through resistors 60B and 60C. When the charge control unit 45 outputs a high signal from a port connected to the resistor 60B of the second output port unit 45C, the LED 60A lights in red, and the port connected to the resistor 60C of the second output port unit 45C When a high signal is output from the LED 60A, the LED 60A lights in green, and when a high signal is output from both the port connected to the resistor 60B and the port connected to the resistor 60C of the second output port 45C. LED 60A lights up in orange. In the present embodiment, the charging control unit 45 lights the LED 60A in red before charging when the battery pack 3 is not connected or waiting for charging, and lights the LED 60A in orange during charging to charge the battery. After completion, the green LED 60A is turned on.

The second control signal transmission unit 62 includes a photocoupler 62A and an FET 62B. The photocoupler 62A transmits a signal for controlling start / stop to the PWM control IC 51A. The FET 62B is connected between the light emitting element constituting the photocoupler 62A and GND, and the gate of the FET 62B is connected to the second output port portion 45C. When a high signal is output from the port connected to the FET 62B in the second output port 45C of the charge control unit 45, the FET 62B is turned on and the photocoupler 62A is turned on. As a result, the PWM control IC 51A is activated and charging is started. When a low signal is output from the port connected to the FET 62B in the second output port portion 45C, the FET 62B is turned off and the photocoupler 62A is turned off. As a result, the PWM control IC 51A stops and charging is stopped (terminated).

Next, charging control by the charging control unit 45 of the charging device 1 will be described. The charging control unit 45 of the charging device 1 according to the present embodiment performs charging control for the purpose of shortening the charging time, in particular, charging of 2C or more for a battery pack having a high capacity (nominal capacity of 5 Ah or more). Control is performed to shorten the charging time by performing so-called 2C charging, which is performed by charging with current.

In a conventional charging device, if a high-capacity battery pack is to be charged with a relatively large charging current (charging current of 2 C or more) with respect to the nominal capacity in order to shorten the charging time, it is a charging target. Since the interruption | blocking element of a battery pack operate | moves for a short time and charge is interrupted, there existed a problem that charge time will become long as a result.

In view of the above problems, in the present embodiment, a charging current of 2 C or more with respect to the nominal capacity (5 Ah or more) of the battery pack (10 A or more when the nominal capacity is 5 Ah, 12 A or more when 6 Ah, that is, 10 A) In the above, charging is started, and in consideration of the breaking characteristics (breaking characteristic curve) of the breaking element of the battery pack, the breaking element does not operate (a range satisfying the breaking characteristics, the breaking characteristic curves in FIGS. 10 and 11). In the lower region), charging is controlled while sequentially changing the target current value so as to charge with as large a charging current as possible. Further, in addition to the above control, charging is started with a charging current of 2C or more with respect to the nominal capacity of the high-capacity battery pack, and even if a charging current of 2C or more flows, the interruption element of the battery pack to be charged When does not operate, the charging is performed with a charging current of 2 C or more from the start of charging until the charging voltage reaches the target charging voltage, and control is performed to shorten the charging time. Note that the charging current is more preferably 2C or more and 3C or less (or 10A or more and 15A or less) in consideration of the balance between the shortening of the charging time and the deterioration and failure of the battery pack due to the charging current. However, the upper limit is not limited to 3C or less, and may be 3C (15A) or more because it varies depending on the manufacturer and performance of the battery cell. The charging device 1 can charge a battery pack of 5 Ah or more with a charging current of 2C (10 A) or more, and can charge a battery pack of less than 5 Ah with a charging current of 2 C or more. Therefore, the conventional battery pack can also shorten the charging time. Furthermore, the charging device 1 can charge not only battery packs connected in series with four cells, but also battery packs with different voltages (5 cells or more and 3 cells or less in series). In this case, the voltage setting control circuit 55 may be configured to be able to set a plurality of target charging voltages so as to be compatible with battery packs having different voltages.

Next, an example of the charging process by the charging device 1 will be described with reference to FIGS. 12 to 14. 12 and 13 are flowcharts illustrating the charging process by the charging control unit 45 of the charging device 1. FIG. 14 is a table for determining a target current value used when the charging control unit 45 charges the battery pack 3.

When charging apparatus 1 is connected to commercial AC power supply P, as shown in FIG. 12, charging control unit 45 starts charging control at S1, and indicates that it is in a charging standby state at S2. The display circuit 60 is lit in red. In order to light the display circuit 60 in red, a high signal is output from the port connected to the resistor 60B among the plurality of ports of the second output port portion 45C, and the LED 60A is lighted in red.

In S2, after the LED 60A is lit red, it is determined in S3 whether or not a battery pack is attached to the battery attachment portion 7 (terminal 70). Whether or not the battery pack is attached is determined by the battery side control unit 3G and the charge control unit 45 of the battery pack communicating through the information communication port 3H and the digital communication port unit 45D. When the battery pack is not attached (S3: No), the process returns to S2. That is, the charging standby state is maintained while repeating S2 and S3 until the battery pack is mounted.

If it is determined in S3 that the battery pack is mounted on the battery mounting portion 7 (S3: Yes), the battery type is determined in S4. The battery type is determined by communication with the battery pack. In the present embodiment, when the battery pack 3 is attached to the battery attachment portion 7 (terminal 70), the charge control portion 45 receives C as the battery type, and when the battery pack 33 is attached, Receive D as seed. In the present embodiment, the battery type is determined by communication with the battery pack. However, when the battery pack is provided with a determination resistor for determining the battery type, the charging device is connected to the determination resistor. The structure which discriminate | determines a battery type by providing the possible discrimination terminal and reading the resistance value of the said discrimination resistance may be sufficient.

After the battery type is determined in S4, the target current value is set to I1 in S5, and charging is started with a charging current of 2C or more, that is, I1 in S6. Charging is started by outputting a high signal from a port connected to the FET 62B of the second control signal transmission unit 62 among the plurality of ports of the second output port unit 45C, and putting the PWM control IC 51A into an operating state. .

When charging is started in S6, the display circuit 60 is lit in orange to indicate that charging is in progress in S7. In order to light the display circuit 60 in orange, a high signal is output from both the port connected to the resistor 60B and the port connected to the resistor 60C among the plurality of ports of the second output port portion 45C. The LED 60A is lit in orange.

In S7, the display circuit 60 is lit in orange, and in S8, the first and second fans 5 and 6 are driven. The first and second fans 5 and 6 are driven by outputting fan control signals from the first output port unit 45B to the first fan control circuit 5A and the second fan control circuit 5B. The first and second fans 5 and 6 generate first and second cooling air, and the air is taken into the case 2 through the air inlet 24a. Thereby, the cooling air path of the charging device 1 toward the first and second exhaust ports 22a and 23a is formed. Further, a cooling air passage for the battery pack from the opening 71 toward the first and second exhaust ports 22a and 23a is also formed.

After the first and second fans 5 and 6 are driven, it is determined in S9 whether or not the battery type is C. When the battery type is C (S9: Yes), it is determined that the battery pack 3 is connected to the charging device 1, and in S10, the target current value corresponding to the battery temperature (ambient temperature) is shown in FIG. Reset (change) according to the table shown. The battery temperature is detected by communication with the battery pack 3 in the same manner as the battery type.

The table shown in FIG. 14 shows that the first cutoff element 3F is charged in the range in which the first cutoff element 3F does not operate (the range in which the charging current is not cut off, the range in which the cutoff characteristic is satisfied). 6 is a correspondence table between battery temperature and target current value determined in consideration of a cutoff characteristic of the element 3F, that is, a first cutoff characteristic curve A.

As shown in FIG. 14, when the battery temperature (ambient temperature) is lower than T1, the target current value is reset (changed) to I1. As shown in FIG. 10, T1 is a value slightly lower than the allowable maximum temperature Ta corresponding to the charging current I1 in the first cutoff characteristic curve A. When the battery temperature is equal to or higher than T1 and lower than T2, the target current value is changed to I2. T2 is a temperature between the allowable maximum temperature Ta corresponding to the charging current I1 and the allowable maximum temperature Tb corresponding to the charging current I2 in the first cutoff characteristic curve A (Ta <T2 <Tb), which is slightly lower than Tb. The value is very low.

According to the first cutoff characteristic curve A, until the battery temperature reaches Ta, I1 that is the maximum current value that can be set by the charging apparatus 1 can be set as the target current value. When the battery temperature rises slightly higher than T1 and reaches Ta when the charging current I1 is flowing, the first interrupting element 3F is opened, the charging current is interrupted, and the charging is interrupted. The target current value is changed to I2 lower than I1 when T1 slightly lower than Ta is reached. Thereby, it can avoid reliably that the 1st interruption | blocking element 3F interrupts | blocks a charging current.

As shown in FIG. 14, when the battery temperature is T2 or more and less than T3, the target current value is set to I3. When the battery temperature is T3 or more and less than T4, the target current value is set to I4, and T4 or more. In this case, the target current value is set to I5. T3 and T2 are determined so as to satisfy Tb <T3 <Tc, T4 is determined so as to satisfy Tc <T4 <Td, and T5 is defined as Td < It is determined to satisfy T5 <Te. T1 to T5 are determined as described above, and the target current value (charging current) is sequentially changed to a smaller value at a temperature slightly lower than the allowable maximum temperature corresponding to the currently set target current value (charging current). By doing so, it is possible to charge with as large a charging current as possible within a range in which the first cutoff element 3F does not operate, and to reliably avoid the first cutoff element 3F from being in an open state and continue charging. Can do. Thereby, the charge time of a high capacity | capacitance battery pack can be shortened. I1 is an example of the “first current value” in the present invention. When I1 is a “first current value”, I2 is an example of a “second current value” in the present invention, and I3 is an example of a “third current value” in the present invention. T1 is an example of the “first temperature threshold” in the present invention. When T1 is a “first temperature threshold value”, T2 is an example of the “second temperature threshold value” in the present invention, Ta is an example of the “first battery temperature” in the present invention, and Tb is the present value. It is an example of "second battery temperature" in the invention.

Returning to FIG. 12, after the target current value is reset (changed) in S10 as described above, it is determined in S11 whether or not full charge has been reached. Full charge is determined as, for example, when the charge current drops below a predetermined end current value under constant voltage control in constant current constant voltage control, which is a general method for charging a lithium ion battery. do it. However, the method of determining full charge is not limited to this.

If it is determined that the battery is fully charged (S11: Yes), charging is terminated in S13. The charging stop process is performed by outputting a low signal from a port connected to the FET 62B among the plurality of ports of the second output port unit 45C and stopping the PWM control IC 51A.

On the other hand, when it is determined that the battery is not fully charged (S11: No), it is determined in S12 whether or not the battery temperature is equal to or higher than T5. T5 is a high temperature that is not normally reached in a state where charging is performed with the charging current I5 and is not suitable for charging for the battery set 3A. When the battery temperature reaches T5 or more, charging is performed. In step S13, charging is stopped.

If it is determined in S12 that the battery temperature is not equal to or higher than T5, the process returns to S10 and is changed again to the target current value corresponding to the battery temperature. That is, the target in which the battery temperature is set while repeating S9, S10, S11, and S12 until it is determined that the battery is fully charged in S11 or the battery temperature is determined to be T5 or higher in S12. Each time the temperature reaches a temperature slightly lower than the allowable maximum temperature corresponding to the current value, the battery pack 3 is charged by the constant current / constant voltage control while the target current value is sequentially changed to a lower current value. Even when the battery temperature drops, the target current value is changed according to the battery temperature after the drop. For example, when the battery temperature falls from a range from T3 to less than T4 to a range from T2 to less than T3, the target current value is changed from I4 to I3 that is larger than I4.

Returning to S9, when it is determined that the battery type is not C, that is, the battery type is D (S9: No), it is determined that the battery pack 33 is attached to the charging device 1, and the processing of S11 and S12 is performed. move on. That is, the target current value changing process in consideration of the cutoff characteristic in S10 is not performed. This is because, in the second cutoff element 33F provided in the battery pack 33, as shown in FIG. 11, the target current values I1 to I5 that can be set by the charging device 1 if the battery temperature is in the range of Tf or less. In any range, the charging current is not cut off, and the maximum of the settable target current values from the start of charging until the charging voltage reaches the target charging voltage within a range where the second cutoff element 33F does not operate. This is because charging is possible with the current value I1, and there is no need to change the target current value.

Note that the second blocking element 33F of the battery pack 33 does not block the charging current as long as it is in the range of Tf or less. If it becomes (S12: Yes), the charging is terminated. As described above, when the battery pack 33 is attached to the charging apparatus 1, the charging voltage from the start of charging at the charging current of 2C, that is, I1, is 1 as long as the battery temperature does not exceed T5 while repeating S9, S11, and S12. The battery is charged until the target charging voltage is reached.

After the charge termination process is performed in S13, as shown in FIG. 13, in S14, the display circuit 60 is lit in green to indicate the charge termination state. In order to light the display circuit 60 in green, a high signal is output from a port connected to the resistor 60C among the plurality of ports of the second output port portion 45C, and the LED 60A is lighted in green.

After the display circuit 60 is lit in green at S14, it is determined at S15 whether the battery temperature is 40 degrees or higher. If the battery temperature is 40 ° C or higher (S15: Yes), S15 is repeated while driving the first and second fans, and the cooling of the battery pack 3 is continued until the battery temperature becomes less than 40 ° C.

When the battery temperature is less than 40 degrees (S15: No), in S16, it is determined whether or not the temperature of the charging circuit unit 4 is 40 degrees or more. The temperature of the charging circuit unit 4 is detected by reading a voltage signal indicating the temperature of the charging circuit unit 4 output from the temperature detection element 44 to the A / D input port unit 45A. If the temperature of the charging circuit unit 4 is 40 ° C. or more (S16: Yes), the process returns to S15 and repeats S15 and S16 until the temperature of the charging circuit unit 4 becomes less than 40 ° C. The driving is continued and cooling of the charging circuit unit 4 is continued. When the temperature of the charging circuit unit 4 becomes less than 40 degrees (S16: No), the driving of the first and second fans 5 and 6 is stopped in S17.

When the battery pack 3 or 33 is being charged in S6 to S13, an air path is formed in the case 2 from the intake port 24a to the first and second exhaust ports 22a and 23a. Since the diode 41, the transformer 42, and the FET 43 are arranged in the vicinity of the air inlet 24a, the air before being heated immediately after being sucked in from the air inlet 24a is cooled as cooling air, so that it is efficiently cooled.

Moreover, since the heat radiation members 46 and 47 define the air path so that the diode 41, the transformer 42, and the FET 43 are included in the air path, the diode 41, the transformer 42, and the FET 43 that require cooling can be efficiently cooled. Furthermore, since the diode 41 and the FET 43 are respectively attached to the heat radiating members 46 and 47, the diode 41 and the FET 43 are efficiently cooled by being exposed to the cooling air flowing along the heat radiating members 46 and 47. Furthermore, since the transformer 42 is located on the most upstream side of the air passage defined by the heat radiating members 46 and 47 (in the vicinity of the intake port 24a), the transformer 42 is efficiently cooled by the air before being warmed.

Returning to the description of the charging process, after stopping the driving of the first and second fans 5 and 6 in S17, it is determined whether or not the battery pack is detached from the charging device 1 in S18. When it is determined that the battery pack is not detached (S18: No), the charging end state is maintained until the battery pack is detached from the charging device 1 while repeating S18. On the other hand, when it is determined that the battery pack has been detached (S18: Yes), the process returns to S2, and the charging standby state is maintained until the battery pack is attached to the charging device 1 again. Thus, according to the charging device 1 of the present embodiment, the battery pack 3 or 33 having a high capacity (5 Ah or more) can be directly charged from the commercial AC power source P with a large current (2 C or more or 10 A or more). And the charging time can be shortened.

Next, with reference to FIGS. 15 (a) and 15 (b), time variations of the battery temperature, the charging voltage, and the charging current of the battery packs 3 and 33 when the above charging process is performed will be described. FIGS. 15A and 15B are time charts showing changes over time in battery temperature, charging voltage, and charging current when charging control by the charging device 1 is performed.

As shown in FIG. 15A, when the battery pack 3 is charged by the charging device 1 according to the present embodiment, the target current value is set to I1 (this embodiment) by the charging control unit 45 at time t0. 12A), that is, a charging current of 2C is set for the nominal capacity 6Ah of the battery pack 3 (corresponding to S5), and charging is started with the charging current I1 (corresponding to S6). When charging is started, the battery pack 3 is charged in a state where the charging current is maintained at I1 by constant current control (corresponding to repetition of S9, S10, S11, and S12). After the time t0, the battery temperature and the charging voltage increase with the charging, and the battery temperature reaches T1 at the time t1.

When the battery temperature reaches T1 at time t1, the charging control unit 45 changes (resets) the target current value from I1 to I2, and the charging current drops from I1 to I2 (corresponding to S10). After the charging current drops to I2, charging is continued in a state where the charging current is maintained at I2 by constant current control (corresponding to repetition of S9, S10, S11 and S12). The charging voltage once decreases as the charging current decreases at time t1, but increases again as charging continues after time t1. Further, the battery temperature rises after time t1, and reaches T2 at time t2.

When the battery temperature reaches T2 at time t2, the charge control unit 45 changes (resets) the target current value from I2 to I3, and the charging current drops from I2 to I3 (corresponding to S10). After the charging current drops to I3, charging is continued in a state where the charging current is maintained at I3 by constant current control (corresponding to repetition of S9, S10, S11, and S12). The charging voltage decreases again as the charging current decreases at time t2, but increases further as charging continues after time t2. Further, the battery temperature further increases after time t2, and reaches T3 at time t3.

When the battery temperature reaches T3 at time t3, the target current value is changed (reset) from I3 to I4 by the charging control unit 45, and the charging current drops from I3 to I4 (corresponding to S10). After the charging current drops to I4, charging is continued in a state where the charging current is maintained at I4 by constant current control (corresponding to repetition of S9, S10, S11, and S12). The charging voltage decreases again as the charging current decreases at time t3, but further increases as charging continues after time t3, and reaches a predetermined target charging voltage at time t5. When the charging voltage reaches the target charging voltage, the charging control unit 45 shifts to constant voltage control, and after time t5, charging is continued in a state where the charging voltage is maintained at the target charging voltage (S9, S10, S11 and Equivalent to repetition of S12). On the other hand, the battery temperature further increases after time t3, but does not reach T4, which is the next temperature threshold used for changing the target current value, at time t5.

After the time t5 when the control is shifted to the constant voltage control, the charging is continued in a state where the charging voltage is maintained at the target charging voltage. However, the charging current is decreased and the battery temperature is decreased and the first fan is also decreased. 5 and the second fan 6 decrease (corresponding to repetition of S9, S10, S11, and S12). Thereafter, when the charging current becomes equal to or less than the predetermined end current value at time t7, the charging control unit 45 determines that the charging is full (S10: equivalent to Yes), and the charging is terminated (corresponding to S13). In FIG. 15A, the charging current is switched when the battery temperature reaches a predetermined value regardless of the charging voltage (battery voltage).

As shown in FIG. 15B, when the battery pack 33 is charged by the charging apparatus 1 according to the present embodiment, the target current value is set to I1 (this embodiment) by the charging control unit 45 at time t0. 12A), that is, a charging current of 2C is set for the nominal capacity 6Ah of the battery pack 33 (corresponding to S5), and charging is started with the charging current I1 (corresponding to S6). When the battery pack 33 is charged, unlike the case where the battery pack 3 is charged, the target current value is not changed according to the battery temperature (S9: No, the process of S10 is not performed), and from the start of charging. Until the charging voltage reaches the target charging voltage (during constant current control), charging is always performed while the charging current is maintained at I1 (corresponding to repetition of S9, S11, and S12). This is because, as described above, the battery packs 3 and 33 both have a nominal capacity of 6 Ah, but have breaker elements with different allowable charge current values and different breakage characteristics. Both the battery temperature and the charging voltage increase with charging after time t0, and reach a predetermined target charging voltage at time t4.

After time t4 when the charging voltage reaches the target charging voltage, charging is continued in a state where the charging voltage is maintained at the target charging voltage. However, as the charging current decreases, the battery temperature also decreases and the charging current decreases. It decreases due to the driving of the first fan 5 and the second fan 6 (corresponding to the repetition of S9, S11 and S12). Thereafter, when the charging current becomes equal to or lower than the predetermined end current value at time t6, the charging control unit 45 determines that the charging is fully charged (corresponding to S10: Yes), and the charging is terminated (corresponding to S13).

As described above, since the charging of the battery pack 33 is performed with the charging current of 2C from the start of charging to the shift to the constant voltage control, the charging end of the battery pack 33 is earlier than the charging end time t7 of the battery pack 3. At time t6. In the present embodiment, the time from time t0 to time t6, that is, the charging time of battery pack 33 by charging device 1 is approximately 30 minutes, and the time from time t0 to time t7, that is, charging device 1 The charging time of the battery pack 3 is approximately 40 minutes.

Here, the time change of the battery temperature, the charging voltage, and the charging current of the battery pack when the charging control by the conventional charging device is performed will be described. FIG. 15C is a time chart showing changes over time in battery temperature, charging voltage, and charging current when charging control is performed by a conventional charging device.

As shown in FIG. 15 (c), in the conventional charging apparatus, the interruption characteristic (interruption characteristic curve) of the interruption element of the battery pack that is the object of charging performed in the present embodiment is considered. The charging current switching control is not performed (the processing corresponding to S10 in FIG. 12 is not performed). Further, in the conventional charging device, when the charging current is charged at 2C or more, the interruption element operates in a short time, and the charging is interrupted or terminated, so the charging current is set to less than 2C. That is, in the conventional charging device, the charging current is set to 8 A so that the interruption element does not operate. FIG. 15C shows a case in which a battery pack having the same nominal capacity as the battery packs 3 and 33 of the present embodiment is charged at 8 A (charge current of less than 2 C) by using a conventional charging device. Is shown.

In the conventional charging device, when charging is started at time t0, the time to reach the target charging voltage is t7, the charging end time is t8, and the charging time is approximately 45 minutes. When the charging device 1 and the conventional charging device are compared with the charging time for a battery pack of the same capacity, the charging device 1 charges the battery pack 33 approximately 30 minutes, and the charging device 1 charges the battery pack 3 About 40 minutes, the charging time in the conventional charging device is about 45 minutes. Thus, the charging time of the battery pack 3 by the charging device 1 and the charging time of the battery pack 33 are both shorter than the charging time in the conventional charging device.

As described above, the charging device 1 according to the first embodiment of the present invention can directly charge the battery pack 3 including the battery set 3A having the battery cells 3a from the commercial AC power source P, and has a nominal capacity of 6 Ah (5 Ah). The battery pack 3 described above is configured to be able to be charged with a charging current of 2C (preferably a charging current of 2C or more and 3C or less). In other words, the battery pack having a nominal capacity α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more (preferably a charging current of 2α or more and 3α or less). For this reason, a high-capacity battery pack can be charged in a short time of about 30 minutes.

Further, the charging device 1 allows the charging current to flow through the battery cell 3a when the interruption characteristic is satisfied, and the first interruption element 3F (second interruption element) that interrupts the charging current when the interruption characteristic is not satisfied. The battery pack 3 (battery pack 33) including the element 33F) can be charged. Further, the plurality of terminals 70 that can be connected to the battery pack 3 (battery pack 33) and the cutoff characteristics of the first cutoff element 3F (second cutoff element 33F), that is, the first cutoff characteristic curve A (second cutoff characteristic curve B). ) And a charge control unit 45 that performs charge control so as to satisfy the cutoff characteristic. For this reason, the charging current is not cut off by the first cutoff element 3F (second cutoff element 33F), and charging is not interrupted or terminated. Thereby, the high-capacity battery pack 3 (battery pack 33) can be charged with a charging current of 2C, and the high-capacity battery pack 3 (battery pack 33) can be charged in a short time.

In the present embodiment, the interruption characteristic of the battery pack 3 (battery pack 33) is satisfied when the charging current is smaller than the allowable maximum current value corresponding to the battery temperature of the battery cell 3a. The charge control unit 45 that acquires the battery temperature of the battery pack 3 (battery pack 33), the current setting circuit 56 that can set one current value among a plurality of current values (I1 to I5), and the set current And a current control circuit 57 that controls the charging current so as to charge the battery pack 3 (battery pack 33) with a single current value. The charging control unit 45 can be set based on the battery temperature. The charging current is controlled so that the battery pack 3 (electric pack 33) is charged with the maximum current value among the current values smaller than the allowable maximum current value corresponding to the battery temperature among I1 to I5. In the present embodiment, when S9: No shown in FIG. 12, that is, when the charging target is the battery pack 33, the charging current switching control (S10) according to the cutoff characteristic is performed. However, the charging current switching control (S10) may be performed on the battery pack 33.

According to the above configuration, for example, when the current value smaller than the allowable maximum current value among the plurality of settable current values (I1 to I5) is I2 to I5, the maximum value among I2 to I5 Battery pack 3 (battery pack 33) can be charged with current value I2. For this reason, the charging time can be further shortened.

Further, in the present embodiment, the allowable maximum current value in the cutoff characteristic of battery pack 3 (battery pack 33) is smaller as the battery temperature is higher, and charge control unit 45 has a higher battery temperature. Accordingly, the charging current is further reduced. That is, in the charging device 1, the charging current can be changed according to the cutoff characteristic of the first cutoff element 3 </ b> F (second cutoff element 33 </ b> F), and thus the first cutoff element 3 </ b> F (second cutoff element 33 </ b> F) is used. It is possible to reliably avoid interruption of the charging current. Thereby, charging time can be shortened reliably.

In the present embodiment, when charging is performed with I1, the charging control unit 45 controls the charging current so that charging is performed with I2 smaller than I1 when the battery temperature becomes T1 or higher. Further, T1 is set to be lower than the battery temperature at which the corresponding allowable maximum current value is I1, that is, Ta. Thereby, interruption of the charging current by the first interruption element 3F (second interruption element 33F) can be avoided more reliably.

More specifically, the allowable maximum current value corresponding to Ta is I1, and when charging is performed at I1, the charging current is cut off by the first cutoff element 3F when the battery temperature reaches Ta. According to the configuration, when the battery temperature reaches T1 lower than Ta, the charging current is changed from I1 to a smaller I2, so that it is possible to more reliably avoid interruption of the charging current by the interruption element.

Further, in the present embodiment, the charging control unit 45 controls the charging current so as to charge with I3 smaller than I2 when the battery temperature becomes T2 higher than T1 when charging with I2. Yes. Further, T2 is set lower than the battery temperature, that is, Tb corresponding to the maximum allowable current value I2, and higher than T2. As a result, it is possible to more reliably avoid interruption of the charging current by the first interruption element 3F and further shorten the charging time.

More specifically, since the temperature threshold T2 for changing the charging current from I2 to a smaller I3 is lower than Tb, the operation of the first cutoff element 3F can be surely avoided. Furthermore, T2 is not higher than Ta, that is, not too low. If T2 is set to an excessively low value, for example, a value lower than Ta, the operation of the first cutoff element 3F can be reliably avoided, but the charging current is reduced from I2 to I3 smaller than I2. The timing to change to is advanced and the charging time cannot be shortened sufficiently. In this regard, by setting T2 higher than Ta as in the present embodiment, the timing for changing to a smaller current value can be delayed, and the charging time can be further shortened. Moreover, since the charging device 1 can alternatively charge a plurality of battery packs having different voltages and different nominal capacities, a plurality of battery packs can be charged by preparing one charging device 1. There is no need to prepare a charging device. Furthermore, since a battery pack with a nominal capacity of less than 5 Ah can be charged with a charging current of 2 C or more, the charging time of a battery pack with a low capacity (less than 5 Ah) can also be shortened.

Next, a modification of the first embodiment will be described with reference to FIGS.

In the charging device 1 of this modification, a heat radiating plate 80 is used instead of the heat radiating members 46 and 47. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

The heat radiating plate 80 defines an air path as cooling air of the air taken in from the intake port 24a and guides it toward the exhaust ports 22a and 23a.

As shown in FIG. 16, the heat radiating plate 80 is large enough to cover the heat generating elements such as the diode 41, the transformer 42, and the FET 43, as shown in FIGS. 16 to 18, when attached to the case 2 of the charging device 1. It is arranged between the upper surface 21 of the case 2 and the diode 41, the transformer 42, and the FET 43.

In the heat dissipation plate 80, openings 81, 82, 83, 84, and 85 having shapes corresponding to the outer shapes of the respective elements are formed at positions corresponding to the diode 41, the transformer 42, and the FET 43, respectively. Further, ribs 81A, 82A, 83A, 84A, and 85A are formed from the vicinity of the edge portions of the openings 81, 82, 83, 84, and 85 toward the substrate 40. For example, the air passage for the transformer 42 reaching the opening 82 from the substrate side of the transformer 42 is defined by the opening 82 formed with respect to the transformer 42 and the rib 82A. Similarly, an air path for the diode 41 is defined by the diode 41, the opening 81, and the rib 81A, and an air path is defined for the heating elements such as the FET 43.

Therefore, when the heat radiating plate 80 is mounted in the case 2, the openings 81, 82, 83, 84, 85 together with the ribs 81 </ b> A, 82 </ b> A, 83 </ b> A, 84 </ b> A, 85 </ b> A provided at the respective peripheral portions, The periphery of the element is surrounded by a slight gap. That is, the heating element is surrounded by the ribs 81A to 85A.

For this reason, when the fans 5 and 6 are driven, as shown in FIGS. 18 to 20, the exhaust ports 22a and 22a are formed from the intake ports 24a through the air passages and openings formed around the corresponding heating elements. A cooling air passage reaching 23a is formed. The first cooling air and the second cooling air pass through the cooling air passage, and each of the diode 41, the transformer 42, and the FET 43, which are heat generating elements, is cooled. In the vicinity of each heating element, an air path is defined between the side surface of the heating element and the corresponding rib, and the cooling air flows toward the opening along the side surface of the heating element. The cooling air that has passed through the opening flows toward the exhaust ports 22a and 23a along the heat radiating plate 80 and is exhausted outside the case 2. Therefore, since the cooling air is configured to be concentrated around the heating elements by the ribs, the heating elements are efficiently cooled, and the temperature rise of the entire charging device 1 is suppressed.

Next, a second embodiment of the present invention will be described with reference to FIGS.

Referring to FIG. 21, the charging device 1 includes a charging circuit unit 104 for charging the battery pack 3, a first fan 105 for cooling the charging circuit unit 104 and the battery pack 3, 2 fans 106.

The case 102 has a substantially rectangular parallelepiped shape, and the upper surface 121 is provided with a battery mounting portion 107 on the front side where the battery pack 3 is mounted for charging. The battery mounting portion 107 is provided with a plurality of terminals 170 for charging the battery pack 3 and an opening 171 through which air for cooling the battery pack 3 passes. Further, the case 102 has four side surfaces 122, 123, 124, and 125 that surround the upper surface 121, and the side surfaces 122 and 123 that are adjacent to each other are connected to each other by a corner portion 126. The side surfaces 122 and 124 face each other, and the side surfaces 123 and 125 face each other.

The first fan 105 is disposed in the case 102 so as to be close to the corner portion 126 and the opening 171 and to face the side surface 122. When driven, the first fan 105 generates first cooling air in the rotation axis direction X. A first exhaust port 122a made up of a plurality of ventilation windows is formed in a portion of the side surface 122 where the first fan 105 faces. When driven, the first fan 105 takes in air from the intake port 124a and generates first cooling air toward the first exhaust port 122a. The first cooling air is exhausted from the case 102 through the first exhaust port 122a.

The second fan 106 is disposed in the case 102 so as to be close to the corner 126 and the opening 171 and to face the side surface 123. When driven, the second fan 106 generates second cooling air in the rotation axis direction Y. At this time, the second fan 106 is disposed such that the rotation axis direction Y intersects the rotation axis direction X of the first fan 105. A second exhaust port 123a including a plurality of ventilation windows is formed in a portion of the side surface 123 that the second fan 106 faces. When driven, the second fan 106 takes in air from the intake port 124a and generates second cooling air toward the second exhaust port 123a. The second cooling air is exhausted from the case 102 through the second exhaust port 123a.

The air inlet 124 a is formed as a plurality of ventilation windows over a predetermined range of the side surface 124 of the case 102. Therefore, when the first and second fans 105 and 106 are driven, air is sucked into the case 102 through the air inlet 124a.

In the charging circuit unit 104, a diode 141, a transformer 142, an FET 143, a temperature detection element 144, and a charging control unit 45 are mounted on a substrate 140. For example, the charging circuit unit 104 uses power supplied from a commercial AC power supply. The battery pack 3 is charged via the terminal 170. When a large amount of current per unit time is passed through the charging circuit unit 104 for rapid charging, the diode 141, the transformer 142, and the FET 143 tend to generate heat and become so-called heating elements. In order to protect these components from heat generation and dissipate heat, for example, the heat radiation members 146 and 147 are attached to the diode 141 and the FET 143, respectively.

The diode 141, the transformer 142, and the FET 143 are disposed in the vicinity of the air inlet 124a, and are directly exposed to the air introduced into the case 102 from the air inlet 124a.

The case 102 has an opening 171 on the upper surface 121, and a first exhaust port 122a, a second exhaust port 123a, and an intake port 124a on the side surface. The flow of air in the case 102 is mainly between the opening 171 and the first exhaust port 122a and the second exhaust port 123a, and between the intake port 124a and the first exhaust port 122a and the second exhaust port 123a. , Formed. The heat dissipating members 146 and 147 are disposed in the air path formed between the air inlet 124a and the first air outlet 122a and the second air outlet 123a, and at least one of the diode 141, the transformer 142, and the FET 143, preferably all of them. Each shape and a position in the case 102 are set so as to include them. Further, the diode 141 and the FET 143 are attached to the heat radiating members 146 and 147 so that the diode 141 and the FET 143 in the case 102 can be cooled by the first and second cooling air. Note that each of the heat dissipation members 146 and 147 does not have the second heat dissipation portion.

The temperature detection element 144 is made of, for example, a thermistor, and detects the temperature inside the case 102.

The charging control unit 45 controls the charging of the battery pack 3 by the charging circuit unit 104 while monitoring the temperature of the battery pack 3, and controls the rotation of the first and second fans 105 and 106.

When the battery pack 3 is being charged, since the two fans 105 and 106 are driven in the case 102, the cooling air taken into the case 2 from the intake port 124a is transmitted to the diode 41, the transformer 42, these heater elements are cooled by passing by the side of the FET 43 and exhausted from the exhaust ports 122a and 123a. Therefore, the temperature rise of the diode 41, the transformer 42, and the FET 43 can be prevented, and the charging device 100 can be efficiently cooled.

Further, the heat radiation members 146 and 147 define an air path so as to surround the diode 141, the transformer 142, and the FET 143, and the first cooling air and the second cooling air are mainly close to the intake ports of the heat radiation members 146 and 147. Since it flows from one end side toward the other end side, the diode 141, the transformer 142, and the FET 143 that need to be cooled can be efficiently cooled. Further, since the diode 141 and the FET 143 are respectively attached to the heat radiating members 146 and 147, the diode 141 and the FET 143 are efficiently cooled by being exposed to the cooling air flowing along the heat radiating members 146 and 147.

Further, since the first fan 105 and the second fan 106 are arranged so that the respective rotation axis directions intersect with each other and are provided at the corners 126 of the case 102, the area for the charging circuit unit 104 is provided. Can be made large in the case 102. Moreover, the passage area of the cooling air can be widened.

Furthermore, since the diode 141, the transformer 142, and the FET 143 are arranged in the vicinity of the air inlet 124a, the air before being heated immediately after being sucked in from the air inlet 124a is cooled as cooling air, so that it is efficiently cooled. The Note that the flow of the cooling air may be reversed. In other words, air may be sucked using the exhaust ports 122a and 123a as the intake port, and air may be discharged using the intake port 124a as the exhaust port.

Next, a modification of the second embodiment will be described below with reference to FIGS.

FIG. 23 shows a charging device 100 </ b> A in which the first fan 105 and the second fan 106 are juxtaposed close to the side surface 123 of the rectangular parallelepiped case 102. The air inlet 124 a is formed on the side surface 125 facing the side surface 123. The other components are the same as those in the second embodiment, and thus detailed description thereof is omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port 124a toward the exhaust ports 122a and 123a, and the diode 141 disposed in the air path. The transformer 142 and the FET 143 are cooled. That is, the heat radiating members 146 and 147 are arranged so as to guide the cooling air from the intake port 124a toward the exhaust ports 122a and 123a (front and rear direction in the figure), and the transformer 142 is arranged between the heat radiating members 146 and 147. doing. By providing the two fans 105 and 106 in the case 102, it is possible to increase the air volume and increase the cooling air passage area, thereby enhancing the cooling effect of the heating elements 141, 142, and 143 and further the charging device 100A.

FIG. 24 shows a charging device 100 </ b> B in which the first fan 105 and the second fan 106 are juxtaposed close to the side surface 122 of the case 102. The air inlet 124 a is formed on the side surface 124 that faces the side surface 122. The other components are the same as those in the second embodiment, and thus detailed description thereof is omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port 124a toward the exhaust ports 122a and 123a, and the diode 141 disposed in the air path. The transformer 142 and the FET 143 are cooled. That is, the heat dissipating members 146 and 147 are arranged so as to guide the cooling air from the intake port 124a toward the exhaust ports 122a and 123a (left and right in the figure), and the transformer 142 is disposed between the heat dissipating members 146 and 147. doing. By providing the two fans 105 and 106 in the case 2, it is possible to increase the air volume and increase the cooling air passage area, thereby enhancing the cooling effect of the heating elements 141, 142, and 143 and the charging device 100A. Note that the flow of the cooling air may be reversed. In other words, air may be sucked using the exhaust ports 122a and 123a as the intake port, and air may be discharged using the intake port 124a as the exhaust port.

FIG. 25 shows a charging device 100 </ b> C in which the first fan 105 and the second fan 106 are juxtaposed in the vertical direction close to the side surface 125 of the case 102. Exhaust ports are respectively formed on the side surfaces 125 in the vicinity of the fans 105 and 106, and intake ports are formed on the side surfaces 123 facing the side surfaces 125. The other components are the same as those in the second embodiment, and thus detailed description thereof is omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142, The FET 143 is cooled. By providing the two fans 105 and 106 in the case 2, it is possible to increase the air volume and enhance the cooling effect of the heating elements 141, 142, and 143, and further the charging device 100A. In FIG. 25, the heat dissipating members 146 and 147 are arranged so as to block the cooling air path from the air inlet 124a to the air outlets 122a and 123a. However, the heat radiating is performed so as to guide the cooling air as shown in FIG. If the members 146 and 147 are arranged, the cooling effect can be enhanced. At this time, if the transformer 142 is disposed between the heat radiation members 146 and 147 in the vicinity of the air inlet 124a, the cooling effect of the transformer 142 in addition to the diode 141 and the FET 143 can be enhanced. Further, the flow of the cooling air may be reversed. In other words, air may be sucked using the exhaust ports 122a and 123a as the intake port, and air may be discharged using the intake port 124a as the exhaust port.

FIG. 26 shows a charging device 100 </ b> D in which the first fan 105 and the second fan 106 are juxtaposed in the vicinity of the position removed from the battery mounting portion 107 on the upper surface 121 of the case 102. An intake port is formed on the upper surface 121 in the vicinity of the fans 105 and 106, and an exhaust port is formed on the side surface 123. The other components are the same as those in the second embodiment, and thus detailed description thereof is omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142, The FET 143 is cooled. By providing the two fans 105 and 106 in the case 2, it is possible to increase the air volume and enhance the cooling effect of the heating elements 141, 142, and 143, and further the charging device 100A. Further, since the two fans 105 and 106 are arranged along the upper surface 121, the arrangement space of the substrate 140 can be secured. Also, the two fans 105 and 106 can be arranged along the upper surface 121 and the side surfaces 122 or 124. As in FIG. 25, the cooling effect can be further enhanced by disposing the heat dissipating members 146 and 147 along the cooling air passage. Further, the flow of the cooling air may be reversed. That is, an exhaust port may be formed on the upper surface in the vicinity of the fan, and air may be sucked by using the exhaust port 123a of the side surface 123 as the intake port.

FIG. 27 shows a charging device 100E in which the first fan 105 is disposed near the side surface 125 and the second fan 106 is disposed near the side surface 123. That is, the first fan 105 and the second fan 106 are arranged on both sides of the charging circuit unit 104 so as to be separated from each other. The intake port is formed on the side surface 125, and the exhaust port is formed on the side surface 123. The other components are the same as those in the second embodiment, and thus detailed description thereof is omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142, The FET 143 is cooled. By providing two fans 105 and 106 in the case 102 and driving one for intake and the other for exhaust, the amount of cooling air flowing in the case 2 is increased and the heating elements 141, 142, 143, The cooling effect of the charging device 100A can be enhanced.

FIG. 28 shows a charging device 100 </ b> F in which the first fan 105 is disposed near the corners of the side surface 124 and the side surface 125, and the second fan 106 is disposed near the corner portion 126. That is, the first fan 105 and the second fan 106 are arranged on both sides of the charging circuit unit 104 so as to be separated from each other. The intake port is formed on the side surface 125, and the exhaust port is formed on the side surface 123. The other components are the same as those in the second embodiment, and thus detailed description thereof is omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142, The FET 143 is cooled. Two fans 105 and 106 are provided at opposite ends in the diagonal direction in the case 102, and one is driven for intake and the other is driven for exhaust, thereby increasing the distance of the air path of the cooling air flowing through the case 2. As a result, the cooling effect of the heating elements 141, 142, 143, and the charging device 100F can be enhanced. Note that the cooling effect can be further enhanced by disposing the heat dissipating members 146 and 147 along the cooling air passages (arrows in the figure). Further, the flow of the cooling air may be reversed. That is, air may be sucked in from the side surface 123 side and air may be discharged from the side surface 125 side.

Next, a charging apparatus 200 according to a third embodiment will be described below with reference to FIG. Regarding the charging device 200, the same members as those in the first embodiment are denoted by the same reference numerals, and different parts will be mainly described below.

Referring to FIG. 29, the charging device 200 includes a charging circuit unit 204 for charging the battery pack 3, a first fan 205 and a first fan 205 for cooling the charging circuit unit 204 and the battery pack 3 in the case 202. 2 fans 206.

The case 202 has a substantially rectangular parallelepiped shape, and a battery mounting portion 207 to which the battery pack 3 is mounted for charging is provided on the upper surface 221 on the front side. The battery mounting unit 207 is provided with a plurality of terminals 270 for charging the battery pack 3 and an opening 271 through which air for cooling the battery pack 3 passes. Further, the case 202 has four side surfaces 222, 223, 224, and 225 that surround the upper surface 221, and the side surfaces 222 and 223 that are adjacent to each other are connected by a corner portion 226.

The first fan 205 is disposed in the case 202 so as to be close to the corner portion 226 and the opening 271 and to face the side surface 222. A first ventilation hole 222a formed of a plurality of ventilation windows is formed in a portion of the side surface 222 facing the first fan 205. When driven, the first fan 205 sucks air from the first vent hole 222a and generates first cooling air with the rotation axis direction X as the blowing direction.

The second fan 206 is disposed in the case 202 so as to be close to the corner portion 226 and the opening 271 and to face the side surface 223. A second ventilation port 223a formed of a plurality of ventilation windows is formed in a portion of the side surface 223 facing the second fan 206. When driven, the second fan 206 sucks air from the second vent 223a and generates second cooling air with the rotation axis direction Y as the blowing direction. The second fan 106 is arranged such that the rotation axis direction Y intersects the rotation axis direction X of the first fan 5.

The first vent 222a and the second vent 223a function as an inlet for taking air into the case 202 while the battery pack 3 is being charged.

Further, a plurality of exhaust windows are formed as exhaust ports 224a over a predetermined range on the side surface 224 of the case 202, and the first and second fans 224a are driven by the first and second fans 205 and 206 through the exhaust ports 224a. 2 Exhaust of cooling air to the case 202 is performed.

The charging circuit unit 204 is mainly mounted with a diode 241, a transformer 242, an FET 243, a temperature detection element 244, and a charging control unit 45 on a substrate 240, and uses, for example, power supplied from a commercial AC power supply. The battery pack 3 is charged via the terminal 270. When a large amount of current per unit time is passed through the charging circuit unit 204 for rapid charging, the diode 241, the transformer 242, and the FET 243 tend to generate heat, and become so-called heating elements. In order to protect these components from heat generation and dissipate heat, for example, heat dissipating members 246 and 247 are attached to the diode 241 and the FET 243, respectively.

The diode 241, the transformer 242, and the FET 243 are disposed in the vicinity of the exhaust port 224a and are directly exposed to the first and second cooling air exhausted from the exhaust port 224a to the outside of the case 202.

The case 202 has an opening 271 on the upper surface 221 and a first ventilation port 222a, a second ventilation port 223a, and an exhaust port 224a on the side surface. The air flow in the case 202 is mainly between the first and second fans 205 and 206 and the opening 271 and between the first and second vent holes 222a and 223a and the exhaust port 224a. It is formed. In particular, the heat radiating members 246 and 247 form an air path between the first vent 222a and the second vent 223a and the exhaust port 224a. Each shape and a position in the case 202 are set so that at least one, preferably all, of the diode 241, the transformer 242, and the FET 243 are included in the air path. Further, the diode 241 and the FET 243 are attached to the heat dissipating members 246 and 247 so that the diode 241 and the FET 243 in the case 202 can be cooled by the first and second cooling air.

The temperature detection element 244 is made of, for example, a thermistor, and detects the temperature inside the case 202.

The charging control unit 45 controls the charging of the battery pack 3 by the charging circuit unit 204 while monitoring the temperature of the battery pack 3, and controls the rotation of the first and second fans 205 and 206.

Next, a first operation of the charging apparatus 200 will be described with reference to FIG.

When the charging device 200 is connected to, for example, a commercial power source, the charging control unit 45 determines whether or not the battery pack 3 is mounted on the battery mounting unit 207 in S111. If the battery pack 3 is mounted (S111: Yes), the first fan 205 is turned on for 5 seconds and the second fan 206 is kept off in S112. At this time, as shown in FIG. 31, the air sucked from the first vent 222 a by the driving of the first fan 205 and the turning off of the second fan 206 becomes the second cooling air from the first fan 205 as the first cooling air. The air is blown toward the vent 223a and the exhaust port 224a. The first cooling air directed toward the second vent 223a is exhausted from the second vent 223a to the outside of the case 202, and dust and the like attached to the second vent 223a is blown out of the case 202.

In step S113, the first fan 205 is turned off and stopped for 5 seconds, and the second fan 206 is turned on and driven. At this time, as shown in FIG. 32, the air sucked from the second vent 223a by the first fan 205 being turned off and the second fan 206 being driven becomes the first cooling air from the second fan 206 as the first cooling air. The air is blown toward the vent 222a and the exhaust 224a. The second cooling air directed toward the first vent 222a is exhausted from the first vent 222a to the outside of the case 202, and dust and the like attached to the first vent 222a are blown out of the case 202.

Although the time in S112 and S113 is 5 seconds in this embodiment, the time is not limited to this time, and may be an appropriate length of time.

In step S114, charging of the battery pack 3 is started, and in step S115, both the first and second fans 205 and 206 are turned on. As shown in FIG. 33, the first and second fans 205 and 206 generate the first and second cooling air, so that the air is taken into the case 202 through the first vent holes 222a and 223a. An air path toward the exhaust port 224a is formed. In addition, an air path from the first ventilation holes 222a and 223a toward the opening 271 is also formed.

When charging of the battery pack 3 is completed in S116, the charging control unit 45 confirms whether or not the temperature of the battery pack 3 is 40 degrees or higher in S117. If the temperature of the battery pack 3 is 40 ° C. or higher (S117: Yes), the first and second fans 205 and 206 are continuously driven (S118), and the cooling of the battery pack 3 is continued.

If the temperature of the battery pack 3 is less than 40 degrees (S117: No), it is confirmed whether the temperature of the charging circuit unit 204 is 40 degrees or more (S119). If the temperature of the charging circuit unit 204 is 40 ° C. or more (S119: Yes), the first and second fans 205 and 206 are continuously driven (S120), and the charging circuit unit 204 is continuously cooled. If the temperature of the charging circuit unit 204 is less than 40 degrees (S119: No), the driving of the first and second fans 205 and 206 is stopped (S121).

On the other hand, when the battery pack 3 is not attached in S111 (S111: No), in S122, the first fan 205 is turned on for 5 seconds, and the second fan 206 is maintained in the off state. . At this time, as shown in FIG. 31, when the first fan 205 is driven and the second fan 206 is turned off, the air sucked from the first vent 222a is supplied as the first cooling air from the first fan 205 to the second air. The air is blown toward the vent 223a and the exhaust port 224a. The first cooling air directed toward the second vent 223a is exhausted from the second vent 223a to the outside of the case 202, and dust and the like attached to the second vent 223a is blown out of the case 202.

Next, in S123, the first fan 205 is turned off and stopped for 5 seconds, and the second fan 206 is turned on and driven. At this time, as shown in FIG. 32, the air sucked from the second vent 223a by the first fan 205 being turned off and the second fan 206 being driven is supplied from the second fan 206 as the second cooling air. The air is blown toward the vent 222a and the exhaust 224a. The second cooling air directed toward the first vent 222a is exhausted from the first vent 222a to the outside of the case 202, and dust and the like attached to the first vent 222a are blown out of the case 202.

Note that the time in S122 and S123 is 5 seconds in this embodiment, but the time is not limited to this time, and may be an appropriate length of time.

Next, it progresses to S124 and each of the 1st fans 205 and 206 is stopped. Next, it progresses to S125 and the charging device 200 waits in S125 until the battery pack 3 is mounted | worn.

In the charging device 200 according to the second embodiment, the first vent 222a and the second vent 223a of the case 202 that are used as the inlet during charging of the battery pack 3 are the same as those of the case 202 in S113 and 112, respectively. Since it functions as an exhaust port for exhausting air to the outside, it is possible to remove dust and the like adhering to the first vent 222a and the second vent 223a from the first vent 222a and the second vent 223a by exhaust. It becomes.

Further, the diode 241, the transformer 242, and the FET 243 serving as heating elements are provided in the vicinity of the exhaust port 224a. Since the first and second cooling airs are focused on the exhaust port 224a for exhausting out of the case, the diode 241, the transformer 242, and the FET 243 are cooled by a relatively high air volume, so that the diodes 241, 242 are efficiently used. FET 243 can be cooled.

Moreover, since the 1st fan 205 and the 2nd fan 206 are arrange | positioned in the case 202 so that each ventilation direction may cross | intersect, it enlarges the cooling area | region in the case 202 by the 1st and 2nd cooling air. Can do. Therefore, not only the battery pack 3 being charged, but also various electronic components such as the diode 241, the transformer 242, and the FET 243 centering on the heat generating elements in the case 202 can be appropriately cooled to be protected from heat generation.

Next, the second operation of the charging apparatus 200 will be described with reference to FIG.

When the charging device 200 is connected to, for example, a commercial power source, in S31, it is determined whether or not the battery pack 3 is attached to the battery attachment portion 7. When the battery pack 3 is attached (S31: Yes), the charging control unit 45 proceeds to S32 and starts charging the battery pack 3. At the same time, in S33, the first fan 205 is turned on to start driving at the same 100% rotational speed as during charging of the battery pack 3. At this time, the second fan 206 is also turned on and driven. If the charging of the battery pack 3 is 100%, the second fan 206 is driven at a rotation speed of 20% for 5 seconds. At this time, as shown in FIG. 35, the air is sucked from the second vent 223a by the driving of the second fan 206, but the rotational speed of the first fan 205 is higher than the rotational speed of the second fan 206. A portion of the first cooling air generated by the first fan 205 is exhausted out of the case 202 through the second vent 223a. For this reason, dust or the like adhering to the second vent 223a is blown out of the case 202 by a part of the first cooling air.

Next, in S34, the second fan 206 is started to be driven at the same 100% rotational speed as during charging of the battery pack 3. At this time, the first fan 205 is driven for 5 seconds at a rotation speed of 20% assuming that charging of the battery pack 3 is 100%. At this time, as shown in FIG. 36, the air is sucked from the first vent 222a by driving the first fan 205, but the rotational speed of the second fan 206 is higher than the rotational speed of the first fan 205. A part of the second cooling air generated by the second fan 206 is exhausted out of the case 202 through the first vent 222a. For this reason, dust or the like attached to the first vent 222a is blown out of the case 202 by a part of the second cooling air.

Although the time in S33 and S34 is 5 seconds in this embodiment, the time is not limited to this time, and can be an appropriate length of time. In addition, although the rotation speed of the second fan 206 and the first fan 205 in S33 and S34 is 20%, the present invention is not limited to this, and cooling air can be exhausted from the second vent 223a or the first vent 222a. An appropriate ratio is selected.

Next, in S35, the first and second fans 205 and 206 are both driven to 100% to generate the first and second cooling air. The battery pack 3 being charged is cooled by the first and second cooling airs, and the heating elements such as the diode 241, the transformer 242, and the FET 243 in the case are cooled to protect these heating elements from heat. .

When the charging of the battery pack 3 is completed in S36, the charging control unit 45 confirms whether or not the temperature of the battery pack 3 is 40 degrees or higher in S37. If the temperature of the battery pack 3 is 40 degrees or more (S37: Yes), the first and second fans 205 and 206 are continuously driven (S38), and the cooling of the battery pack 3 is continued.

If the temperature of the battery pack 3 is less than 40 degrees (S37: No), it is confirmed whether or not the temperature of the charging circuit unit 204 is 40 degrees or more (S39). If the temperature of the charging circuit unit 204 is 40 ° C. or higher (S39: Yes), the driving of the first and second fans 205 and 206 is continued (S40), and the cooling of the charging circuit unit 204 is continued. If the temperature of the charging circuit unit 204 is less than 40 degrees (S39: No), the driving of the first and second fans 205 and 206 is stopped (S41).

On the other hand, if the battery pack 3 is not attached at S31 (S31: No), the first fan 205 is turned on for 5 seconds and the second fan 206 is kept off at S42. . At this time, when the first fan 205 is driven and the second fan 206 is turned off, the air sucked from the first vent 222a becomes the first cooling air from the first fan 205 to the second vent 223a and the exhaust port 224a. It is blown toward and. The first cooling air directed toward the second vent 223a is exhausted from the second vent 223a to the outside of the case 202, and dust and the like attached to the second vent 223a is blown out of the case 202.

Next, in S43, the first fan 205 is turned off and stopped for 5 seconds, and the second fan 206 is turned on and driven. At this time, when the first fan 205 is turned off and the second fan 206 is driven, the air sucked from the second vent 223a becomes the second cooling air from the second fan 206 to the first vent 222a and the exhaust vent 224a. It is blown toward and. The second cooling air directed toward the first vent 222a is exhausted from the first vent 222a to the outside of the case 202, and dust and the like attached to the first vent 222a are blown out of the case 202.

Next, it progresses to S44 and each of the 1st fans 205 and 206 is stopped. Next, it progresses to S45 and the charging device 200 waits in S45 until the battery pack 3 is mounted | worn. When the attachment of the battery pack 3 is detected in S45, the process returns to S31.

In the second operation of the charging device 200 according to the second embodiment, at the same time as the charging of the battery pack 3 is started, the rotational speed of one of the first and second fans 205 and 206 is set to the value of the other fan. By making it larger than the number of revolutions, the cooling air generated by the fan with the high number of revolutions is exhausted from the vents corresponding to the fans with the small number of revolutions, and thereby the air attached to the vents corresponding to the fan with the small number of revolutions. Dust and the like are blown out of the case 202. Next, the first fan 205 and the second fan 206 are rotated at opposite speeds, so that dust or the like adhering to the other vent is blown out of the case 202. Therefore, clogging of the first and second vents that occur during charging of the battery pack 3 can be eliminated.

Further, the diode 241, the transformer 242, and the FET 243 serving as heating elements are provided in the vicinity of the exhaust port 224a. Since the first and second cooling airs are focused on the exhaust port 224a for exhausting out of the case, the diode 241, the transformer 242, and the FET 243 are cooled by a relatively high air volume, so that the diodes 241, 242 are efficiently used. FET 243 can be cooled.

Furthermore, since the 1st fan 205 and the 2nd fan 206 are arrange | positioned in the case 202 so that each ventilation direction may cross | intersect, rather than arrange | positioning so that the ventilation direction of two fans may become mutually parallel. The cooling area in the case 202 by the first and second cooling air can be widened. Therefore, not only the battery pack 3 being charged, but also various electronic components such as the diode 241, the transformer 242, and the FET 243 centering on the heat generating elements in the case 202 can be appropriately cooled to be protected from heat generation.

In the above embodiment, the first vent 222a and the second vent 223a are separated by the corner 226. However, in other embodiments, the first vent 222a and the second vent 223a may be formed continuously over the side surfaces 222, 223. Similarly, the first vent 222a and the second vent 223a are separated by a corner 226. However, in other embodiments, the first vent 222a and the second vent 223a may be formed continuously over the side surfaces 222, 223.

The charging device according to the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the invention described in the claims.

For example, the air path of the cooling air may be configured as shown in FIGS. In the charging apparatus 1 of the fourth embodiment, the plate 300 formed integrally with the case 2 together with the heat radiating members 46 and 47 is used instead of the heat radiating plate 80 of the first embodiment instead of the cooling air flow path. use. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

The plate 300, together with the heat radiating members 46 and 47, defines an air path as cooling air for the air taken in from the intake port 24a and guides it toward the exhaust ports 22a and 23a.

As shown in FIG. 37, the plate 300 is provided integrally or separately with the case 2 on the inner peripheral surface on the case upper surface side in the case 2 of the charging device 1. When separate from the case 2, it is fixed to the inner peripheral surface of the case 2 with screws (not shown) or the like. In the assembled state of the charging device 1, the plate 300 covers the heat generating elements such as the diode 41, the transformer 42, and the FET 43, that is, covers the air path formed by the heat radiating members 46 and 47. It is located above and has a size and shape along the longitudinal direction of the heat dissipating members 46 and 47. The plate 300 is disposed between the upper surface 21 of the case 2 and the diode 41, the transformer 42, and the FET 43.

In the first embodiment, the upper portion of the transformer 42 is open, but in this embodiment, the plate 42 covers the transformer 42. Therefore, the cooling efficiency of the transformer 42 can be increased.

Therefore, when the fans 5 and 6 are driven, as shown in FIG. 38, the cooling from the intake port 24a to the exhaust ports 22a and 23a through the air passage formed by the heat radiating members 46 and 47 and the plate 300 is performed. An air path is formed. The first cooling air and the second cooling air pass through the cooling air passage, and each of the diode 41, the transformer 42, and the FET 43, which are heat generating elements, is cooled. Since the heating element is covered with the plate 300 above each heating element, the cooling air surely passes around the heating element, the heating element is efficiently cooled, and the temperature rise of the entire charging device 1 is suppressed. .

In the above-described embodiment, the battery pack and the heating element are cooled by providing a plurality (two) of fans. However, when a battery pack having a nominal capacity of 5 Ah or more is charged with a charging current of 2 C or more or 10 A or more, a plurality of fans or only one fan may be used as long as the air volume is sufficient to cool the battery pack and the heating element. But you can.

In the fifth embodiment, as shown in FIG. 39, a single fan 6 is used. The fan may be arranged at any position such as the position of the fan 5 in FIG. 4 or the positions of the fans 105 and 106 in FIGS.

When charging the battery pack with a charging current of 10 A or more, the air flow in the case 2 by the single fan 6 is 13.0 m ^ 3 / hr (13 cubic meters per hour) or more, preferably 13.5 m ^ 3 / hr With the above configuration, charging can be performed while suppressing heat generation of the heat generating element. At that time, the wind pressure is preferably 0.0015 Pa or more. Further, as shown in FIG. 4 and the like, the air volume generated in the case 2 by a plurality of fans may be 13.0 m ^ 3 / hr or more. Therefore, when the battery pack is charged with a charging current of 10 A or more, a single fan may be used as long as the air volume in the case 2 can be 13 m ^ 3 / hr or more.

DESCRIPTION OF SYMBOLS 1,100,200 ... Charging device, 2,102,202 ... Case, 3,33 ... Battery pack, 3a ... Battery cell, 3F ... First interruption | blocking element, 4,104,204 ... Charging circuit part, 5,105, 205 ... 1st fan, 6, 106, 206 ... 2nd fan, 7 ... Battery mounting part, 22a, 122a ... 1st exhaust port, 23a, 123a ... 2nd exhaust port, 222a ... 1st ventilation port, 223a ... 1st 2 vents, 33F ... second blocking element, 41,141,241 ... diode, 42,142,242 ... transformer, 43,143,243 ... FET, 45 ... charge control unit, 46,47 ... radiating member, 46A, 47A ... 1st heat radiation part, 46B, 47B ... 2nd heat radiation part, 56 ... Current setting circuit, 57 ... Current control circuit, 70 ... Terminal

The present invention relates to a battery pack charging device for a power tool that charges a battery pack for a power tool composed of a secondary battery such as a nickel / cadmium battery, a nickel / hydrogen battery, or a lithium ion battery.

In order to solve the above problems, the present invention provides a battery pack charging device for a power tool that can charge a battery pack for a power tool including a secondary battery, and the battery pack having a nominal capacity of 5 Ah or more is 2 C or more. Provided is a battery pack charging device for an electric tool , characterized in that it can be charged with a charging current of.

In order to solve the above problems, the present invention further provides a battery pack charging device for a power tool that can charge a battery pack for a power tool including a secondary battery, wherein the nominal capacity is α (α is 5 or more). (Real number) A battery pack charging device for an electric tool , characterized in that the battery pack of Ah or more can be charged with a charging current of 2αA or more.

In order to solve the above problems, the present invention further provides a secondary battery and a charging current that is allowed to flow through the secondary battery when a predetermined condition is satisfied and does not satisfy the predetermined condition. A battery pack charging device for a power tool capable of charging a battery pack for a power tool, comprising: a battery connecting portion connectable to the battery pack; and a battery connecting portion connected to the battery connecting portion. A battery pack charging device for a power tool , comprising: charge control means for specifying the predetermined condition of the blocking means of the battery pack and performing charge control so as to satisfy the predetermined condition. .

In order to solve the above-mentioned problem, the present invention further provides a battery pack for a power tool that can directly charge a battery pack for a power tool including a secondary battery from a commercial AC power source, and has a nominal capacity of 5 Ah or more. Provided is a battery pack charging device for an electric tool , characterized in that the battery pack can be charged with a charging current of 2C or more and 3C or less.

In order to solve the above-mentioned problems, the present invention further provides a battery pack charging device for a power tool that can directly charge a battery pack for a power tool including a secondary battery from a commercial AC power source, and has a nominal capacity of α (α Provides a battery pack charging device for a power tool , characterized in that the battery pack can be charged with a charging current of 2αA or more and 3αA or less.

Claims (15)

A charging device capable of charging a battery pack including a secondary battery,
A charging device configured to be able to charge the battery pack having a nominal capacity of 5 Ah or more with a charging current of 2 C or more. A charging device capable of charging a battery pack including a secondary battery,
A charging device characterized in that the battery pack having a nominal capacity α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more. The battery pack further includes a blocking unit that allows a charging current to flow through the secondary battery when a predetermined condition is satisfied, and blocks the charging current when the predetermined condition is not satisfied,
A battery connecting portion connectable to the battery pack;
Charging control means for specifying the predetermined condition of the blocking means of the battery pack connected to the battery connecting portion and performing charge control so as to satisfy the predetermined condition;
The charging device according to claim 1, further comprising: A battery pack comprising: a secondary battery; and a blocking means that allows a charging current to flow through the secondary battery when the predetermined condition is satisfied and blocks the charging current when the predetermined condition is not satisfied. A rechargeable charging device,
A battery connecting portion connectable to the battery pack;
Charging control means for specifying the predetermined condition of the blocking means of the battery pack connected to the battery connecting portion and performing charge control so as to satisfy the predetermined condition;
A charging device comprising: The charging device according to claim 4, wherein the battery pack having a nominal capacity of 5 Ah or more is configured to be charged with a charging current of 2 C or more. 5. The charging device according to claim 4, wherein the battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more. The predetermined condition is satisfied when the charging current is smaller than an allowable maximum current value corresponding to the battery temperature of the secondary battery,
The charge control means includes
Battery temperature acquisition means for acquiring the battery temperature of the battery pack;
Current setting means capable of setting one current value from a plurality of current values;
Current control means for controlling a charging current so as to charge the battery pack with the set one current value;
Have
Based on the battery temperature, the charging current is controlled so as to charge the battery pack with a maximum current value among current values smaller than an allowable maximum current value among the settable current values. The charging device according to any one of claims 3 to 6, characterized in that: The allowable maximum current value in the predetermined condition becomes smaller as the battery temperature becomes higher,
8. The charging apparatus according to claim 7, wherein the charging control unit reduces the charging current as the battery temperature increases. The charging control means controls the charging current so that charging is performed at a second current value smaller than the first current value when the battery temperature is equal to or higher than the first temperature threshold when charging is performed at the first current value. And
9. The charging device according to claim 7, wherein the one temperature threshold is lower than a first battery temperature at which the corresponding maximum allowable current value is the first current value. In the case where the charging control unit is charged with the second current value, a third current value smaller than the second current value when the battery temperature is equal to or higher than a second temperature threshold value higher than the first temperature threshold value. Control the charging current to charge with,
10. The second temperature threshold value according to claim 9, wherein the corresponding maximum allowable current value is lower than the second battery temperature, which is the second current value, and higher than the first battery temperature. Charging device. The charging device according to any one of claims 3 to 10, wherein the blocking means is a thermal protector. The charging device according to claim 3, wherein the blocking means is a fuse. A plurality of battery packs having different voltages and different nominal capacities can be alternatively charged,
The charging device according to claim 1, wherein the battery pack having a nominal capacity of less than 5 Ah is configured to be charged with a charging current of 2 C or more. A charging device capable of directly charging a battery pack including a secondary battery from a commercial AC power source,
A charging device configured to be able to charge the battery pack having a nominal capacity of 5 Ah or more with a charging current of 2C or more and 3C or less. A charging device capable of directly charging a battery pack including a secondary battery from a commercial AC power source,
A charging device, wherein the battery pack having a nominal capacity α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more and 3αA or less.

Images