JP3783573B2

JP3783573B2 - DC power supply with charging function

Info

Publication number: JP3783573B2
Application number: JP2001111023A
Authority: JP
Inventors: 信宏高野; 岳史武田; 栄二中山; 一彦船橋
Original assignee: Hitachi Koki Co Ltd
Current assignee: Koki Holdings Co Ltd
Priority date: 2001-04-10
Filing date: 2001-04-10
Publication date: 2006-06-07
Anticipated expiration: 2021-04-10
Also published as: JP2002315223A

Description

【０００１】
【発明の属する技術分野】
本発明は、着脱可能な電池パックを電源とするコードレス電動工具等のコードレスツールに着脱可能なアダプタを備えたケーブルを介して直流電圧を供給すると共に電池パックを充電する充電機能付き直流電源装置に関するものである。以下説明の便宜上コードレスツールをコードレス電動工具(以下単に電動工具という)に特定して説明する。
【０００２】
【従来の技術】
電動工具は電源ケーブルによる作業上の制約が無く、どのような場所においても作業できるというメリットを有しているが、電池パックの容量が低下すると電池パックを充電するか別の充電済み電池パックと交換しなければならないという問題があった。そこで、作業場所と交流電源設置場所が近く作業中の移動が少ない場合には交流を直流に変換する直流電源装置を用い、作業場所と交流電源設置場所が遠く作業中の移動が多い場合には電池パックを用い、作業状況に合わせて電動工具の電源として電池パックと直流電源を併用していた。
【０００３】
しかし、作業場所に充電器と直流電源を持ち込まなければ効率のよい作業ができないという問題がある。この問題を解決するため、特開２０００−１８４６１４号において、電動工具の動作を検出し、電動工具の動作時は充電をしないで直流電源を供給し、電動工具の動作が停止している時は電池パックを充電する充電機能付き直流電源装置を提案した。
【０００４】
【発明が解決しようとする課題】
特開２０００−１８４６１４号は、電池パックの充電中に電動工具の電源スイッチがオンされた時、マイコンは電源であるＤＣ−ＤＣコンバータをオフする信号を出力してＤＣ−ＤＣコンバータを一旦オフし、充電するか電源供給するかを切り換えるスイッチを充電側から電動工具駆動側へ切り換え、その後再びＤＣ−ＤＣコンバータをオンさせるため、電池パックの充電中に電動工具の電源スイッチがオンされた時、瞬時に電動工具を駆動することができず、使用者に違和感を与える。これは、ＤＣ−ＤＣコンバータを一度オフした後に再びオンさせるためであり、充電か電源供給かを切り換えるのが一つのスイッチで行われているためである。
【０００５】
本発明の目的は、上記した従来技術の欠点をなくし、電池パックの充電中に電動工具の電源スイッチがオンされた時、瞬時に充電を停止すると共に電動工具への電源供給に切り換えるようにし、使用者に違和感を与えることがない充電機能付き直流電源装置を提供することである。
【０００６】
【課題を解決するための手段】
上記目的は、電動工具の電源スイッチのオンを検出した瞬間に充電不許可信号及び電動工具への電源供給を許可する許可信号を出力するトリガ検出手段と、電源出力を電動工具に供給可能にする電源出力スイッチ回路と、電池パックへの充電を可能にする充電出力スイッチ回路を有する電源出力切り換え手段と、電池パックへの充電電流を制御する充電電流制御回路と、電動工具への供給電圧を制御する駆動電圧制御回路を有する電源出力制御手段とを備え、充電中に電源スイッチがオンされた時、瞬時にトリガ検出手段の出力に基づいて充電から電源供給に切り換えるようにすることにより達成される。
【０００７】
【発明の実施の形態】
図１は本発明充電機能付き直流電源装置の一実施形態を示す斜視図である。１はＡＣコード組、２は充電機能付き直流電源装置本体(以下単に電源装置本体という)、３はアダプタ組であり、一端に電動工具４に接続するアダプタプラグ、他端に直流電源装置本体２に接続する出力ケーブルとを有する。アダプタプラグは、上部が電池パック５の挿入部と同じ形状をしており、電池パック５と同様に電動工具４に着脱可能となっている。
【０００８】
図２は充電機能付き直流電源装置の一実施形態を示すブロック図である。ＡＣコード組１はＡＣ１００Ｖの商用交流電源に接続される。２は電源装置本体、アダプタ組３は複数の電動工具４に対し、各々の定格電圧に対応する電圧を出力させるための出力電圧設定手段３ａを備えている。電動工具４はＤＣモータ４ａ及び直列に接続された電源スイッチ４ｂを内蔵し、電源スイッチ４ｂがオンされた時、アダプタ組３を介して、電源装置本体２から直流電源が供給される。５は電動工具４に装着可能な電池パックで、充電可能な蓄電池５ａ及び蓄電池５ａの近傍または接触されて取り付けられる温度素子５ｂ（例えばサーミスタ等）から構成される。
【０００９】
スイッチング電源１０は、第一整流平滑回路１１、高周波トランス１２、第二整流平滑回路１３、スイッチング素子１４、スイッチング制御回路１５等から構成され、スイッチング制御回路１５はスイッチング素子１４の駆動パルス幅を変えて第二整流平滑回路１３の出力電圧及び出力電流を調整する。
【００１０】
電源出力制御手段２０は、電源スイッチ４ｂのオン時に電動工具４の駆動電圧を制御し、電源スイッチ４ｂのオフ時で電池パック５が充電可能な場合に充電電流を制御する電圧・電流制御回路２１、駆動電圧及び充電電流の値を設定する電圧・電流設定回路２２から構成される。電動工具４が駆動している時は、電圧検出回路４２の信号に基づきスイッチング制御回路１５に帰還をかけスイッチング素子１４のスイッチングデューティを制御し、同時に出力電流検出回路４１からの信号に基づきアダプタ組３のケーブルにおける電圧降下分を補正する機能を有する。また電源スイッチ４ｂのオフ時で電池パック５が充電可能な場合は、出力電流検出回路４１からの信号に基づききスイッチング制御回路１５に帰還をかけ、スイッチング素子１４のスイッチングデューティを制御し、電池パック５への充電電流を電池状態検出手段５０の出力に基づいて制御する。
【００１１】
電源出力切り換え手段３０は、電源スイッチ４ｂのオン時に電源出力を電動工具４に供給可能にする電源出力スイッチ回路３１、電動工具４の未使用時に電池パック５への充電を可能にする充電出力スイッチ回路３２から構成される。
【００１２】
電源出力検出手段４０は、電源スイッチ４ｂのオン時に電動工具４に供給される電流または電源スイッチ４ｂのオフ時に電池パック５に供給される充電電流を検出する出力電流検出回路４１、第二整流平滑回路１３の出力電圧を検出する電圧検出回路４２、電源スイッチ４ｂがオンされたことを検出し、その瞬間に充電不許可信号及び電動工具４への電源供給を許可する信号を出力するトリガ検出回路４３、アダプタ組３の出力電圧設定手段３ａの設定電圧を検出する出力電圧設定検出回路４４等から構成される。
【００１３】
電池状態検出手段５０は、蓄電池５ａの電池電圧を検出する電池電圧検出回路５１、電池パック５内の温度素子５ｂの特性に応じて電池温度を検出する電池温度検出回路５２から構成される。
【００１４】
本発明制御手段を構成するマイコン６０は、電源出力検出手段４０の出力及び電池状態検出手段５０の出力に基づいて、電動工具４の駆動電圧の設定、電動工具４の未使用時における電池パック５への充電電流の設定を行うと共に、電動工具４の未使用、すなわち電源スイッチ４ｂのオフ及び電池状態検出手段５０の出力に基づき充電可能か否かを判別し、電池パック５が充電可能な時はトリガ検出回路４３を介して充電出力スイッチ回路３２に充電許可信号を出力する等の機能を有する。
【００１５】
例えばＬＥＤ等から構成される表示回路７０は、マイコン６０の出力に基づいて、電動工具４が使用中、使用可能か否かの表示、または電池パック５が充電中であること等を表示する。補助電源回路８０は、マイコン６０等の電源及び電源出力制御手段２０、電源出力検出手段４０及び電池状態検出手段５０等に基準電圧Ｖｃｃを供給する。
【００１６】
次に電池パック５の充電中に電源スイッチ４ｂがオンされた時、瞬時に充電を停止すると共に電動工具４への電源供給に切り換える動作について図３を参照して説明する。
【００１７】
電圧・電流制御回路２１は、電動工具４の駆動電圧を制御する駆動電圧制御回路２１ａ、蓄電池５ａへ供給する充電電流を制御する充電電流制御手段２１ｂ、スイッチング制御回路１５に所定の駆動電圧及び充電電流に制御すべく帰還をかける伝達手段であるフォトカプラ２１ｃ、ダイオード２１ｄ、２１ｅ、デジタルトランジスタ２１ｆ、２１ｇ、充電出力スイッチ回路３２からの信号を反転するインバータ２１ｈ等から構成されている。
【００１８】
充電出力スイッチ回路３２は、蓄電池５ａへ供給する充電電流をオンオフさせるリレー３２ａ、リレー３２ａを駆動するデジタルトランジスタ３２ｂ、トリガ検出回路４３及びマイコン６０の出力信号の論理和により充電を許可するアンド回路３２ｃ、トリガ検出回路４３の出力信号を反転させるインバータ３２ｄ等から構成される。
【００１９】
出力電流検出回路４１は、シャント抵抗４１ａ、シャント抵抗４１ａの出力を増幅し、その電流値をマイコン６０に入力する電流検出回路４１ｂから構成されている。
【００２０】
トリガ検出回路４３は、コンパレータ４３ａ、抵抗４３ｂ〜４３ｋ、ダイオード４３ｌ、デジタルトランジスタ４３ｍ等から構成される。トリガ検出回路４３は、電源スイッチ４ｂがオンした時にコンパレータ４３ａの出力が論理値１となるように構成されている。具体的には、電動工具４の未使用時すなわち電源スイッチ４ｂがオフの時、第二整流平滑回路１３の出力電圧Ｖｏｕｔを抵抗４３ｂ、４３ｃで分圧した電圧がコンパレータ４３ａの反転入力端子に印加され、第二整流平滑回路１３の出力電圧Ｖｏｕｔを抵抗４３ｊ、４３ｋで分圧した電圧を更に抵抗４３ｄ、４３ｅで分圧した電圧がコンパレータ４３ａの非反転入力端子に印加され、この時これら抵抗４３ｂ〜４３ｅの抵抗値はコンパレータ４３ａの出力が論理値０となるように設定される。電源スイッチ４ｂがオンの時は、直流モータ４ａの直流抵抗は抵抗４３ｊに比べ非常に小さい（数オーム程度）ので、コンパレータ４３ａの非反転入力端子に印加される電圧は第二整流平滑回路１３の出力電圧Ｖｏｕｔを抵抗４３ｄ、４３ｅで分圧した電圧となって、コンパレータ４３ａの出力は論理値１となり、これにより電源スイッチ４ｂがオンされたと判別する。抵抗４３ｄ、４３ｅの分圧比は、抵抗４３ｂ、４３ｃの分圧比より大きくなるよう設定されておりこの結果コンパレータ４３ａは論理値１の出力となる。コンパレータ４３ａの出力が論理値１となった時すなわち電源スイッチ４ｂがオンされた時、コンパレータ４３ａの出力はダイオード４３ｌ、抵抗４３ｈを介して非反転入力端子に帰還され、コンパレータ４３ａの出力は論理値１のままラッチされ、ＦＥＴからなる電源出力スイッチ回路３１は常にオンされ電動工具４の駆動が維持される。
【００２１】
電動工具４の使用から未使用状態になり、その後蓄電池５ａの充電への切り換えは、マイコン６０が電動工具４の未使用を電流検出回路４１ｂの出力から検出し、トリガ検出回路４３のデジタルトランジスタ４３ｍのベースに印加する論理値１の信号を出力してコンパレータ４３ａのラッチ動作を解除することにより行われる。ラッチ動作が解除されれば、コンパレータ４３ａの出力は論理値０となり電源出力スイッチ回路３１がオフされて電動工具４への電源供給が禁止される。一方、充電出力スイッチ回路３２のアンド回路３２ｃの一方の入力端子にはインバータ３２ｄを介して論理値１の信号が印加されると共にマイコン６０から論理値１の充電許可信号がアンド回路３２ｃの他方の入力端子に印加されてアンド回路３２ｃは論理値１の出力を発生するので、デジタルトランジスタ３２ｂを介してリレー３２ａがオンされて蓄電池５ａに充電電流が供給されるようになる。
【００２２】
この充電許可時において、アンド回路３２ｃの論理値１の信号は、電圧・電流制御回路２１のインバータ２１ｈを介してデジタルトランジスタ２１ｇをオンさせて電動工具４の駆動電圧を制御する駆動電圧制御回路２１ａを動作不能にする。これと同時に電圧・電流制御回路２１のデジタルトランジスタ２１ｆはオフし充電電流制御手段２１ｂを動作可能にして充電電流の制御が可能になる。
【００２３】
上記とは逆に充電中に電動工具４の電源スイッチ４ｂがオンされた時は、上記した如く、コンパレータ４３ａの出力は論理値１となり、充電出力スイッチ回路３２のアンド回路３２ｃの一方の入力端子には論理値０の信号が印加されるので、マイコン６０から論理値１の充電許可信号が発生されていたとしてもアンド回路３２ｃの出力は論理値０となり、デジタルトランジスタ３２ｂがオフしてリレー３２ａもオフされ蓄電池５ａへの充電電流の供給は遮断される。
【００２４】
また、この充電中から電動工具４の電源スイッチ４ｂがオンされた時、アンド回路３２ｃの論理値０の信号は、電圧・電流制御回路２１のインバータ２１ｈを介してデジタルトランジスタ２１ｇをオフさせ、電動工具４の駆動電圧を制御する駆動電圧制御回路２１ａを動作可能にし、一方、電圧・電流制御回路２１のデジタルトランジスタ２１ｆをオフさせ、充電電流制御手段２１ｂを動作不能にする。
【００２５】
上記した実施形態によれば、電池パック５が充電中であっても電動工具４の電源スイッチ４ｂがオンされた場合、電動工具４に瞬時に直流電力を供給できるようになるので、使用者は違和感を持つことなく電動工具を使用できるようになり、電動工具の使い勝手を向上できる。
【００２６】
【発明の効果】
以上のように本発明によれば、電動工具の動作時に電池パックを充電せず電動工具に直流電源を供給し、電動工具未使用時に電池パックへの充電が可能な充電機能付き電源電装置において、電池パックの充電中に電動工具の電源スイッチがオンされれば、瞬時に充電を停止し、電動工具への電源供給に切り換えるので、使用者に違和感を与えない充電機能付き直流電源装置を提供することができる。
【図面の簡単な説明】
【図１】本発明充電機能付き直流電源装置の一実施形態を示す斜視図。
【図２】本発明充電機能付き直流電源装置の一実施形態を示すブロック回路図。
【図３】図２の本発明スイッチ動作検出手段の一例を示すブロック回路図。
【符号の説明】
２は直流電源装置本体、３はアダプタ組、４は電動工具、５は電池パック、１０はスイッチング電源、２０は電源出力制御手段、３０は電源出力切り換え手段、４０は電源出力検出手段、４３はトリガ検出回路、５０は電池状態検出手段、６０はマイコンである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a DC power supply device with a charging function that supplies a DC voltage via a cable having an adapter that can be attached to and detached from a cordless tool such as a cordless electric tool that uses a detachable battery pack as a power source and charges the battery pack. Is. Hereinafter, for convenience of explanation, the cordless tool will be described as being a cordless power tool (hereinafter simply referred to as a power tool).
[0002]
[Prior art]
The power tool has the advantage of being able to work in any place without any power cable restrictions, but if the battery pack capacity drops, the battery pack can be recharged or another charged battery pack. There was a problem that had to be replaced. Therefore, if the work place is close to the AC power supply installation location and there is little movement during work, use a DC power supply device that converts AC to DC, and if the work place is far from the AC power supply installation place and there is much movement during work A battery pack was used, and a battery pack and a DC power source were used in combination as the power source of the electric tool according to the work situation.
[0003]
However, there is a problem that efficient work cannot be performed unless a charger and a DC power supply are brought into the work place. In order to solve this problem, in Japanese Patent Laid-Open No. 2000-184614, when the operation of the electric tool is detected, the DC power is supplied without charging when the electric tool is operating, and the operation of the electric tool is stopped. We proposed a DC power supply with a charging function to charge the battery pack.
[0004]
[Problems to be solved by the invention]
In Japanese Patent Laid-Open No. 2000-184614, when the power switch of the electric tool is turned on while the battery pack is being charged, the microcomputer outputs a signal to turn off the DC-DC converter that is the power supply and temporarily turns off the DC-DC converter. When the power switch of the power tool is turned on during charging of the battery pack, the switch for switching between charging or power supply is switched from the charging side to the power tool driving side, and then the DC-DC converter is turned on again. The electric tool cannot be driven instantaneously, giving the user a sense of incongruity. This is because the DC-DC converter is turned off and then turned on again, and switching between charging and power supply is performed by one switch.
[0005]
The object of the present invention is to eliminate the drawbacks of the prior art described above, and when the power switch of the power tool is turned on during charging of the battery pack, the charging is instantaneously stopped and switched to power supply to the power tool, It is to provide a DC power supply device with a charging function that does not give a sense of incongruity to a user.
[0006]
[Means for Solving the Problems]
The object is to provide a trigger detection means for outputting a charging non-permission signal and a permission signal for permitting power supply to the power tool at the moment when the power switch of the power tool is detected, and to enable power supply to be supplied to the power tool. A power supply output switch circuit, a power supply output switching means having a charge output switch circuit that enables charging of the battery pack, a charge current control circuit that controls a charge current to the battery pack, and a supply voltage to the power tool are controlled. And a power supply output control means having a drive voltage control circuit that performs the switching from charging to power supply instantaneously based on the output of the trigger detection means when the power switch is turned on during charging. .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view showing an embodiment of a DC power supply device with a charging function according to the present invention. 1 is an AC cord set, 2 is a DC power supply main body with a charging function (hereinafter simply referred to as a power supply main body), 3 is an adapter set, an adapter plug connected to the electric tool 4 at one end, and a DC power supply main body 2 at the other end And an output cable connected to the. The upper part of the adapter plug has the same shape as the insertion part of the battery pack 5 and can be attached to and detached from the electric tool 4 in the same manner as the battery pack 5.
[0008]
FIG. 2 is a block diagram showing an embodiment of a DC power supply device with a charging function. The AC cord set 1 is connected to an AC 100V commercial AC power source. Reference numeral 2 denotes a power supply device body, and the adapter set 3 includes output voltage setting means 3a for outputting a voltage corresponding to each rated voltage to a plurality of power tools 4. The electric power tool 4 includes a DC motor 4a and a power switch 4b connected in series. When the power switch 4b is turned on, DC power is supplied from the power supply device body 2 via the adapter set 3. A battery pack 5 that can be attached to the electric tool 4 includes a rechargeable storage battery 5a and a temperature element 5b (for example, a thermistor) that is attached in the vicinity of or in contact with the storage battery 5a.
[0009]
The switching power supply 10 includes a first rectifying / smoothing circuit 11, a high-frequency transformer 12, a second rectifying / smoothing circuit 13, a switching element 14, a switching control circuit 15 and the like. The switching control circuit 15 changes the drive pulse width of the switching element 14. The output voltage and output current of the second rectifying / smoothing circuit 13 are adjusted.
[0010]
The power output control means 20 controls the drive voltage of the electric tool 4 when the power switch 4b is turned on, and controls the charging current when the battery pack 5 can be charged when the power switch 4b is turned off. And a voltage / current setting circuit 22 for setting values of the driving voltage and the charging current. When the power tool 4 is driven, the switching control circuit 15 is fed back based on the signal from the voltage detection circuit 42 to control the switching duty of the switching element 14, and at the same time, the adapter assembly is set based on the signal from the output current detection circuit 41. 3 has a function of correcting a voltage drop in the cable 3. Further, when the battery pack 5 can be charged when the power switch 4b is turned off, feedback is given to the switching control circuit 15 based on a signal from the output current detection circuit 41, and the switching duty of the switching element 14 is controlled. 5 is controlled based on the output of the battery state detecting means 50.
[0011]
The power output switching means 30 includes a power output switch circuit 31 that can supply power output to the power tool 4 when the power switch 4b is turned on, and a charge output switch that enables charging of the battery pack 5 when the power tool 4 is not used. The circuit 32 is configured.
[0012]
The power output detection means 40 includes an output current detection circuit 41 for detecting a current supplied to the electric tool 4 when the power switch 4b is turned on or a charging current supplied to the battery pack 5 when the power switch 4b is turned off. A voltage detection circuit 42 that detects the output voltage of the circuit 13, a trigger detection circuit that detects that the power switch 4 b is turned on and outputs a charging non-permission signal and a signal that permits power supply to the power tool 4 at that moment. 43, an output voltage setting detection circuit 44 for detecting the set voltage of the output voltage setting means 3a of the adapter set 3 and the like.
[0013]
The battery state detection means 50 includes a battery voltage detection circuit 51 that detects the battery voltage of the storage battery 5a, and a battery temperature detection circuit 52 that detects the battery temperature in accordance with the characteristics of the temperature element 5b in the battery pack 5.
[0014]
The microcomputer 60 constituting the control means of the present invention sets the drive voltage of the electric tool 4 and the battery pack 5 when the electric tool 4 is not used based on the output of the power output detection means 40 and the output of the battery state detection means 50. When the electric power tool 4 is not used, that is, whether or not charging is possible is determined based on the power switch 4b being turned off and the output of the battery state detecting means 50, and the battery pack 5 can be charged. Has a function of outputting a charge permission signal to the charge output switch circuit 32 via the trigger detection circuit 43.
[0015]
For example, the display circuit 70 constituted by an LED or the like displays, based on the output of the microcomputer 60, an indication as to whether or not the electric power tool 4 is in use or usable, or that the battery pack 5 is being charged. The auxiliary power supply circuit 80 supplies the reference voltage Vcc to the power supply and power supply output control means 20, the power supply output detection means 40, the battery state detection means 50, etc. of the microcomputer 60 and the like.
[0016]
Next, when the power switch 4b is turned on while the battery pack 5 is being charged, the operation for instantaneously stopping the charging and switching the power supply to the power tool 4 will be described with reference to FIG.
[0017]
The voltage / current control circuit 21 includes a drive voltage control circuit 21a for controlling the drive voltage of the electric tool 4, charging current control means 21b for controlling a charging current supplied to the storage battery 5a, and a predetermined drive voltage and charge for the switching control circuit 15. It is composed of a photocoupler 21c, diodes 21d and 21e, digital transistors 21f and 21g, which are transmission means for applying feedback to control the current, an inverter 21h that inverts a signal from the charge output switch circuit 32, and the like.
[0018]
The charge output switch circuit 32 turns on and off the charging current supplied to the storage battery 5a, the digital transistor 32b that drives the relay 32a, the trigger detection circuit 43, and the AND circuit 32c that permits charging by the logical sum of the output signals of the microcomputer 60. , And an inverter 32d for inverting the output signal of the trigger detection circuit 43.
[0019]
The output current detection circuit 41 includes a shunt resistor 41 a and a current detection circuit 41 b that amplifies the output of the shunt resistor 41 a and inputs the current value to the microcomputer 60.
[0020]
The trigger detection circuit 43 includes a comparator 43a, resistors 43b to 43k, a diode 43l, a digital transistor 43m, and the like. The trigger detection circuit 43 is configured such that the output of the comparator 43a becomes a logical value 1 when the power switch 4b is turned on. Specifically, when the power tool 4 is not used, that is, when the power switch 4b is OFF, the voltage obtained by dividing the output voltage Vout of the second rectifying and smoothing circuit 13 by the resistors 43b and 43c is applied to the inverting input terminal of the comparator 43a. The voltage obtained by dividing the output voltage Vout of the second rectifying / smoothing circuit 13 by the resistors 43j and 43k is further applied to the non-inverting input terminal of the comparator 43a by the resistors 43d and 43e. At this time, the resistors 43b The resistance values of .about.43e are set so that the output of the comparator 43a becomes a logical value of zero. When the power switch 4b is on, the DC resistance of the DC motor 4a is very small (about several ohms) compared to the resistor 43j, so the voltage applied to the non-inverting input terminal of the comparator 43a is The output voltage Vout is divided by the resistors 43d and 43e, and the output of the comparator 43a becomes a logical value 1, thereby determining that the power switch 4b is turned on. The voltage dividing ratio of the resistors 43d and 43e is set to be larger than the voltage dividing ratio of the resistors 43b and 43c. As a result, the comparator 43a outputs a logical value 1. When the output of the comparator 43a becomes the logical value 1, that is, when the power switch 4b is turned on, the output of the comparator 43a is fed back to the non-inverting input terminal via the diode 43l and the resistor 43h, and the output of the comparator 43a is the logical value. The power output switch circuit 31 composed of an FET is always turned on and the driving of the power tool 4 is maintained.
[0021]
When the power tool 4 is changed from being used to being unused, and then the storage battery 5a is switched to charging, the microcomputer 60 detects that the power tool 4 is not used from the output of the current detection circuit 41b, and the trigger transistor 43 has a digital transistor 43m. This is performed by outputting a signal of logical value 1 applied to the base of the comparator 43a and releasing the latch operation of the comparator 43a. When the latch operation is released, the output of the comparator 43a becomes a logical value 0, the power output switch circuit 31 is turned off, and the power supply to the power tool 4 is prohibited. On the other hand, a signal of logical value 1 is applied to one input terminal of the AND circuit 32c of the charging output switch circuit 32 via the inverter 32d, and a charging permission signal of logical value 1 is sent from the microcomputer 60 to the other input terminal of the AND circuit 32c. When applied to the input terminal, the AND circuit 32c generates an output of logical value 1, so that the relay 32a is turned on via the digital transistor 32b, and the charging current is supplied to the storage battery 5a.
[0022]
When this charging is permitted, a signal having a logical value 1 of the AND circuit 32c is supplied to the drive voltage control circuit 21a that controls the drive voltage of the electric tool 4 by turning on the digital transistor 21g via the inverter 21h of the voltage / current control circuit 21. Make inoperable. At the same time, the digital transistor 21f of the voltage / current control circuit 21 is turned off, and the charge current control means 21b can be operated to control the charge current.
[0023]
Contrary to the above, when the power switch 4b of the power tool 4 is turned on during charging, the output of the comparator 43a becomes a logical value 1 as described above, and one input terminal of the AND circuit 32c of the charge output switch circuit 32 Since a signal having a logical value of 0 is applied to the AND circuit 32c, the output of the AND circuit 32c becomes a logical value of 0 even if a charge permission signal having a logical value of 1 is generated from the microcomputer 60, the digital transistor 32b is turned off, and the relay 32a Is also turned off, and the supply of the charging current to the storage battery 5a is cut off.
[0024]
In addition, when the power switch 4b of the electric tool 4 is turned on during this charging, the logical value 0 signal of the AND circuit 32c turns off the digital transistor 21g via the inverter 21h of the voltage / current control circuit 21, thereby The drive voltage control circuit 21a for controlling the drive voltage of the tool 4 is enabled, while the digital transistor 21f of the voltage / current control circuit 21 is turned off to disable the charge current control means 21b.
[0025]
According to the above-described embodiment, when the power switch 4b of the electric tool 4 is turned on even when the battery pack 5 is being charged, the user can instantaneously supply DC power to the electric tool 4, so that the user can The power tool can be used without a sense of incongruity, and the usability of the power tool can be improved.
[0026]
【The invention's effect】
As described above, according to the present invention, in the power supply device with a charging function that can supply the DC power to the electric tool without charging the battery pack when the electric tool is operated and can charge the battery pack when the electric tool is not used. If the power switch of the power tool is turned on while the battery pack is being charged, the charging is stopped instantaneously and the power supply is switched to the power tool, thus providing a DC power supply with a charging function that does not give the user a sense of incongruity can do.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a DC power supply device with a charging function according to the present invention.
FIG. 2 is a block circuit diagram showing an embodiment of a DC power supply device with a charging function according to the present invention.
FIG. 3 is a block circuit diagram showing an example of the switch operation detecting means of the present invention shown in FIG. 2;
[Explanation of symbols]
2 is a DC power supply main body, 3 is an adapter set, 4 is an electric tool, 5 is a battery pack, 10 is a switching power supply, 20 is a power output control means, 30 is a power output switching means, 40 is a power output detection means, and 43 is A trigger detection circuit, 50 is a battery state detection means, and 60 is a microcomputer.

Claims

A cordless tool that has a power switch and is driven by using a detachable battery pack as a power source, and a DC that has a battery pack insertion slot into which a battery pack to be charged is inserted after the input AC is converted into a direct current and output. A battery pack comprising: a power supply main body; and an adapter that can be attached to and detached from the cordless tool through an insertion portion having the same shape as the tool insertion portion of the battery pack, and that is supplied with the output of the DC power supply main body to be a power source for the cordless tool Or a DC power supply device with a charging function that selectively performs DC power supply to the cordless tool via an adapter,
Power supply output control means for controlling the output of the DC power supply main body in response to power supply to the cordless tool and charging to the battery pack; and power supply output switching means for switching power supply to the cordless tool or charging to the battery pack. A DC power supply device with a charging function, comprising: a trigger detection means for outputting a charging non-permission signal and a signal for permitting power supply to the cordless tool at the moment when the power switch on of the cordless tool is detected.

2. The charging function according to claim 1, wherein the power output switching means comprises a power output switch circuit that enables power supply to be supplied to the cordless tool and a charge output switch circuit that enables charging of the battery pack. DC power supply with

3. The charging function according to claim 2, wherein the trigger detection means outputs a signal for turning on the power output switch circuit and a signal for turning off the charge output switch circuit when the power switch of the cordless tool is turned on. DC power supply with

The power supply output control means includes a voltage / current control circuit for controlling the output voltage and output current of the DC power supply main body, and the voltage / current control circuit includes a charging current control circuit for controlling the charging current to the battery pack, and a cordless A drive voltage control circuit that controls the supply voltage to the tool, and based on the output of the charge output switch circuit, the charge current control circuit is switched to the drive voltage control circuit when using the cordless tool, and the charge current control circuit is switched when using the cordless tool. The DC power supply device with a charging function according to claim 2 or 3.

A cordless tool that has a power switch and is driven by using a detachable battery pack as a power source, and a DC that has a battery pack insertion slot into which a battery pack to be charged is inserted after the input AC is converted into a direct current and output. A battery pack comprising: a power supply main body; and an adapter that can be attached to and detached from the cordless tool through an insertion portion having the same shape as the tool insertion portion of the battery pack, and that is supplied with the output of the DC power supply main body to be a power source for the cordless tool Or a DC power supply device with a charging function that selectively performs DC power supply to the cordless tool via an adapter,
Power supply output control means for controlling the output of the DC power supply unit in response to power supply to the cordless tool or charging to the battery pack, and power supply output switching means for switching power supply to the cordless tool or charging to the battery pack, respectively Battery state detection means for detecting the state of the battery pack, trigger detection means for detecting the power switch on of the cordless tool, output current detection means for detecting the output current of the DC power supply main body, output current detection means, A DC power supply with a charging function, comprising: control means for switching to charging the battery pack when the cordless tool is not used, based on the output of the battery state detecting means.