JP2014226032A - Battery pack, charging system to charge battery pack, and power tool having battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack capable of charging by a contact or non-contact manner, a charging system, and a power tool.SOLUTION: A battery pack 200 comprises: a plurality of battery cells 202; a substrate 208 mounting a charging circuit 250; a terminal 210 for connecting electrically with an external device; and a power receiving coil 240 capable of receiving power from the outside by a non-contact manner. The power receiving coil 240 is installed between the battery cells 202 and a lower part 224 of a housing 230, and the substrate 208 is installed between an upper part 226 of a housing 220 and the battery cells 202. The battery pack 200 is connected to a power tool 100 through the terminal 210 to drive the power tool 100. The power receiving coil 240 is arranged within a prescribed distance from a power supply coil 301 of a power supply device 300, thereby, power can be supplied by the non-contact manner to charge the battery cells 202. Furthermore, the battery cells can be also charged by connecting to a charging device through the terminal 210.

Description

  The present invention relates to a secondary battery for a cordless power tool that can be charged in a non-contact state, a charging system that charges the battery pack, and a power tool including the battery pack.

  In power tools, cordless power tools that do not require a cord and are easy to handle even when used outdoors have become widespread. As a power source of the cordless electric tool, a secondary battery such as a nickel cadmium battery (hereinafter referred to as a nickel cadmium battery), a nickel metal hydride battery, or a lithium ion battery is used.

  When charging such a cordless power tool, most of the charging side such as the cordless power tool or the battery pack is charged by electrical contact with a charging device on the charging side by a metal contact. However, in working environments where electric tools are used, cutting scraps generated when cutting building materials, etc., and moisture, such as rain, are particularly likely to adhere to the metal contacts of the contact portion for electrical connection when outdoors. , Tend to cause contact failure. In addition, when charged objects generated by the human body come into contact with the metal contacts, the battery is protected from over-discharge and over-charge, etc., which are built into internal circuits such as lithium ion batteries in general. There is also a possibility that electrostatic breakdown may occur in a protection circuit or the like.

  Since the above is assumed when charging is performed using a metal contact, a non-contact charging method is also conceivable. For example, an electric tool has been proposed in which power is supplied in a non-contact state by a separation transformer between a charger and a battery pack and between the battery pack and a tool body (see, for example, Patent Document 1). ).

Japanese Patent Laying-Open No. 2005-73350 (page 4-5, FIG. 1)

  It is an object of the present invention to provide a battery pack that can be charged in a non-contact manner and that can stably drive an electric tool, a charging system that charges the battery pack, and an electric tool including the battery pack.

  Another object of the present invention is to enable charging of the battery pack while maintaining the connection state between the battery pack and the power tool.

  In order to achieve the above object, the invention described in claim 1 contains at least one battery cell, and includes an upper part, a lower part located on the side facing the upper part, and an upper part and a lower part. A housing having a side portion that is a portion for connecting the power tool, a metal terminal for supplying power to the power tool by being electrically connected to the power tool, a substrate on which the metal terminal is disposed, and electromagnetic induction A power receiving coil that receives charging power from the power supply device; and a charging circuit that supplies the charging power received by the power receiving coil to the battery cell, the substrate is disposed on the upper side of the housing, and the metal terminal is The battery pack is disposed outside the housing of the substrate, and the receiving coil is disposed on the lower side of the housing.

  According to such a structure, a metal terminal is used as an electrical connection means when connecting a battery pack and an electric tool. The power receiving coil is provided on a side different from the metal terminal of the battery pack. Since it has a charging circuit, it is charged by supplying power from the outside.

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, the power receiving coil is disposed on the lower side of the battery cell and in the housing.

  According to such a configuration, the power receiving coil is provided on the side opposite to the side to which a device such as a power tool is connected.

  The invention described in claim 3 is the invention described in claim 1 or 2, characterized in that the charging circuit is mounted on a substrate.

  According to such a configuration, a space for mounting the charging circuit is efficiently secured.

  According to a fourth aspect of the present invention, in the second or third aspect of the present invention, the power supply line further includes a power supply line that is pulled out from the power reception coil and connected to the charging circuit. The battery is connected to a charging circuit through the battery cell.

  According to such a configuration, the feeder line supplies power to the charging circuit while maintaining insulation from the battery cell and the outside of the housing.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the charging circuit is smoothed by a smoothing circuit for smoothing power from the power receiving coil and a smoothing circuit. And a charge control circuit for charging the battery cell using the obtained electric power.

  According to such a configuration, the battery pack is smoothed and charged with controlled electric power.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the battery cell is a lithium ion battery cell, and is mounted on a substrate for protecting the battery cell. It further has a protection circuit.

  According to such a configuration, when safety such as overcharging of the lithium ion battery is concerned, a signal corresponding thereto is output to the outside through the metal terminal.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the metal terminal includes a charging terminal for supplying charging power to the battery cell. .

  According to such a configuration, charging power is supplied to the battery pack by connecting the charger to the metal terminal.

  The invention according to claim 8 is electrically connected to the battery pack according to any one of claims 1 to 7 and the battery pack according to any one of claims 1 to 7. And a charging device that charges the battery pack.

  In this charging system, the charging device is electrically connected to the battery pack, and supplies charging power to the battery pack to charge the battery cells.

  The invention according to claim 9 is an electric tool comprising the battery pack according to any one of claims 1 to 7 and driven by being supplied with electric power from the battery pack. is there.

  According to such a configuration, the electric tool is driven while being connected to the battery pack by contact, and electric power is supplied in a non-contact manner when the battery pack is charged.

  According to invention of Claim 1, an electric tool can be driven by connecting a battery pack and an electric tool with a metal terminal. At this time, the metal terminal of the battery pack and the power receiving coil are provided on different sides, and the electric tool does not necessarily need to be disconnected from the battery pack during charging.

  According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, it is possible to have a configuration in which a device such as a power tool is placed on the power supply device in a state of being connected to the battery pack. It is. Moreover, it can charge with the state mounted in that way.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, the metal terminal and the charging circuit can be efficiently arranged, and the enlargement of the battery pack can be prevented. .

  According to the invention described in claim 4, in addition to the effect of the invention described in claim 2 or claim 3, it is possible to prevent a short circuit from occurring between the battery cell and an object outside the housing.

  According to the fifth aspect of the present invention, in addition to the effects of the first to fourth aspects of the invention, it is possible to prevent problems such as overcharge, heating, and lifetime reduction during charging of the battery pack. Is possible.

  According to the invention described in claim 6, in addition to the effects of the invention described in claims 1 to 5, the battery cell can be used for safe charging and driving of the electric tool even if the battery cell is a lithium ion battery. Is possible.

  According to the invention described in claim 7, in addition to the effects of the invention described in claims 1 to 6, the battery cell can be charged by connecting a charger to the metal terminal. Therefore, a method of receiving only power supply in a non-contact state from the outside via a power receiving coil and controlling charging with an internal charging circuit, and a charging circuit of the charger by electrically connecting the charger by contact There are two methods of charge control and two types of charge.

  According to the invention described in claim 8, the charging device can be connected to the battery pack by contact, and the battery pack is connected and controlled by contact with an external charging device instead of being supplied with electric power without contact. It can be charged by being supplied with the charged power.

  According to the ninth aspect of the present invention, the electric power tool is connected to the battery pack by contact connection, and power is reliably and efficiently supplied. When charging, it is possible to supply power without contact.

  As described above, according to the battery pack, the charging system for charging the battery pack, and the electric tool including the battery pack according to the present invention, charging can be performed in a non-contact manner and in a contact manner. In some cases, it is possible to obtain an excellent effect that it can be performed in a contact state.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic perspective view seen from the side of the electric tool by one embodiment of this invention, a battery pack, and an electric power supply apparatus. The perspective view from the upper part of the battery pack by this Embodiment. The perspective view of the battery pack and charging device by this Embodiment. The typical sectional view in the IV-IV section of Drawing 1 of the battery pack by this embodiment. The typical sectional view in the VV section of Drawing 1 of the battery pack by this embodiment. The block diagram which shows the battery pack and electric power supply apparatus by this Embodiment.

  A battery pack, a charging system for charging the battery pack, and a power tool including the battery pack according to an embodiment of the present invention will be described with reference to FIGS. In the drawings, the top, bottom, front and back are determined as shown in each figure.

  FIG. 1 is a diagram schematically illustrating a non-contact charging using the battery pack according to the present embodiment and a connection state with a power tool by a schematic perspective view. As shown in FIG. 1, the battery pack 200 according to the present embodiment drives the electric tool 100 by moving the electric power tool 100 such as an electric drill in the arrow A direction and electrically connecting it. Further, the battery pack 200 is charged by being fed by the power supply device 300.

  As shown in FIGS. 1 to 3, the battery pack 200 includes an upper housing 220 and a lower housing 230 that are divided at a boundary portion 250, and a plurality of battery cells 202 are accommodated therein. In the example of FIG. 1, at least eight battery cells 202 are stored. These battery cells are connected to each other in a predetermined connection state to form a battery cell set and output predetermined power. The battery cell 202 is a secondary battery such as a lithium ion battery.

  As shown in FIGS. 1 and 2, the upper housing 220 includes an upper part 226 and a side part 228. The upper part 226 is configured such that the front protrudes upward and the terminal 210 is disposed in the center part in the front-rear direction, and the rear part is formed below the front part side. The side surface portion 228 is formed so as to continuously surround the upper portion 226 in a substantially vertical direction, and forms a part of the side surface of the battery pack 200. An operation portion 223 is formed on a part of the side surface portion 228. The operation unit 223 is a member for releasing the engagement with the power tool or the like by pressing the battery pack 200 when the battery pack 200 is attached to or detached from the power tool or the like.

  As shown in FIGS. 1 and 3, the lower housing 230 includes a lower part 224 and a side part 222. The lower side portion 224 forms the bottom surface of the lower housing 230. The side surface portion 222 is formed so as to continuously surround the lower side portion 224 in a substantially vertical direction, and forms a part of the side surface of the battery pack 200.

  As shown in FIGS. 1 and 4, a substrate 208 is provided on the inner side of the upper portion 226 of the upper housing 220 and the lower housing 230 (also collectively referred to as housings 220 and 230). The substrate 208 is provided with a plurality of terminals 210 for electrical connection with external devices. For example, the terminal 210A can be a positive terminal connected to the positive side of the battery cell set, and the terminal 210B can be a negative terminal connected to the negative side of the battery cell set. The battery pack 200 supplies driving power to the electric power tool 100 via these terminals 210A and 210B, or is supplied with charging power when connected to a charging device.

  Further, a charging circuit 250 for charging the battery cell 202 and a protection circuit 252 for preventing overcharge, overdischarge, overcurrent, etc. when the battery cell 202 is a lithium ion battery are mounted on the substrate 208. Yes. When the protection circuit 252 detects overcharge, overdischarge, overcurrent, or the like of the battery cell 202, the protection circuit 252 transmits a signal to the charge circuit 250 to stop charging, or to stop power supply to the connected power tool 1. To do.

  As shown in FIGS. 1 and 5, the power receiving coil 240 is disposed between the lower side portion 224 inside the lower housing 230 and the battery cell 202. The power receiving coil 240 is connected to the charging circuit 252 of the substrate 208 through a wire 206 serving as a power feeding line. The power receiving coil 240 is supplied with electric power from the power supply device 300 by electromagnetic induction and receives power, thereby becoming a supply source of charging power for the battery cell 202. The wire 206 is inside the housings 220 and 230 and passes between the side portions 222 and 228 and the battery cell 202 to connect the power receiving coil 240 and the charging circuit 250.

  As shown in FIG. 1, the electric power tool 100 connected to the battery pack 200 according to the present embodiment is an electric drill, for example, and includes a main body portion 102, a handle portion 106 formed to extend from the main body portion 102, and It has a drill bit 104 attached to the tip of the main body. A drive circuit 113 is formed inside the main body portion 102, and a motor 115 is provided inside the handle portion 106. A terminal 111 for electrical connection with the battery pack 200 is provided at the lower end of the handle portion 106. The power tool 100 is configured to be supplied with power by being connected to the battery pack 200 via the terminal 111, and to drive the drill bit 104 by driving the motor 115 by the drive circuit 113 to perform a predetermined work. Yes.

  Next, electrical configurations and operations of the battery pack 200 and the power supply device 300 according to the present embodiment will be described with reference to FIGS. 1 and 6. As shown in FIGS. 1 and 6, the power supply device 300 includes a rectifier circuit 305, a high-frequency oscillation circuit 303, and a power supply coil 301, and is connected to a power source 307 such as a household commercial power source via the connection unit 303. It works by connecting.

  The battery pack 200 serving as a charging unit includes a power receiving coil 240 that receives power, a charging circuit 250 that charges the battery cell 202 with the received power, and a plurality of battery cells 202. The charging circuit 250 includes a resonance capacitor 254 that transmits the power received by the power receiving coil, a smoothing circuit 256 that smoothes the power output from the resonance capacitor 254, a charging current according to the type and connection state of the battery cell 202, and the like. It has a charge control circuit 258 that controls the charging voltage and outputs the charging power.

  An operation during charging of the power supply device 300 and the battery pack 200 configured as described above will be described. First, the power supply 307 and the power supply apparatus 300 are connected by the connection unit 303. The rectifier circuit 305 rectifies the AC power supplied from the power supply 307. The high-frequency oscillator circuit 303 converts the power rectified by the rectifier circuit 305 into a high-frequency voltage. An AC magnetic flux is generated in the feeding coil 301 by this high frequency voltage.

  Due to this AC magnetic flux, an induced electromotive force is generated in the power receiving coil 240 of the battery pack 200 according to Faraday's law. The resonance capacitor 254 is configured to transmit more power by reducing the coupling impedance between the power supply device 300 on the power supply side and the battery pack 200 on the power reception side by resonance. . The induced electromotive force transmitted by the resonance capacitor 254 is smoothed by the smoothing circuit 256. The smoothed electric power is supplied to the charging control circuit 258, and charging is performed with a charging current and a charging voltage corresponding to the type and connection state of the battery cell 202. At this time, when the overcharge and overcurrent are detected by the protection circuit 252, the charging is stopped.

  As described above, the battery pack 200 according to the present embodiment drives the electric power tool 100 by being connected to the electric power tool 100 via the terminal 210. Thus, since the electric tool 100 is driven by contact with a terminal, stable driving is possible.

  By arranging the power feeding coil 301 of the power supply device 300 and the power receiving coil 240 of the battery pack 200 within a predetermined distance, power from a commercial power source or the like can be received via the power supply device 300. The battery pack 202 can charge the battery cell 202 by the received power. With such a configuration, electric power can be supplied in a non-contact manner, so that contact failure due to cutting waste or electrostatic breakdown due to charged materials or the like does not occur at a work site or the like. On the other hand, when it is desired to perform charging in a short time, the charging can be performed by connecting to an external charging device 10 via the terminal 210 and configuring the charging system 20 as shown in FIG. As described above, since charging can be performed by either contact or non-contact methods, the battery can be selectively used according to the situation, and a useful battery pack is obtained.

  Further, the battery pack 200 has a protection circuit 252 and stops charging when an overcharge, overcurrent, or the like of the battery cell 202 is detected. When overdischarge is detected, power supply to the connected power tool 100 and the like is stopped. By including the protection circuit 252 as described above, it is possible to safely charge and drive the power tool.

  Since the charging circuit 250 and the protection circuit 252 are mounted on the substrate 208 provided with the terminals 210, the space in the battery pack can be used efficiently, and the battery pack 200 does not increase in size. Since the wire 206 passes between the battery cell 202 and the housings 220 and 230, the wire 206 can be reliably electrically disconnected from the battery cell 202 and the outside.

  Further, the battery pack 200 drives the electric power tool 100 by being connected to the electric power tool 100. However, since the board 208 and the power receiving coil 240 are provided on the opposing surfaces, the connection with the electric power tool 100 is continued. The battery can be charged by being placed on the power supply device 300 as shown in FIG.

  The battery pack, the charging system for charging the battery pack, and the electric tool including the battery pack according to the present invention are not limited to the above-described embodiments, and various modifications and improvements can be made within the scope described in the claims. Is possible. For example, the power receiving coil 240 is provided between the lower side portion 224 of the housing 220 and the battery cell 202, but may be provided between the side surface portion 222 or the side surface portion 228 and the battery cell 202. At this time, the wire 206 connecting the substrate 208 and the power receiving coil 240 can be shortened, and there are effects such as noise prevention and short circuit prevention.

  In the above embodiment, the housings 220 and 230 are divided and have a substantially rectangular parallelepiped shape with an unevenness on the upper part. However, the battery cell 202, the substrate 208, the power receiving coil 240, etc. can be accommodated without such a form. Any structure can be used as long as the terminal 210 can be installed and the substrate 208 and the power receiving coil 240 can be arranged at different locations.

  The battery pack of the present invention, the charging system for charging the battery pack, and the electric tool provided with the battery pack can be used as a power source for electric equipment such as an electric tool, a charging system, and an electric tool.

DESCRIPTION OF SYMBOLS 100: Electric tool 200: Battery pack 202: Battery cell 206: Wire 208: Board | substrate 210: Terminal 220, 230: Housing 222, 228: Side part 224: Lower part 226: Upper part 250: Charging circuit 252: Protection circuit 240 : Power receiving coil 300: Power supply device 301: Power feeding coil

  The present invention relates to a secondary battery for a cordless power tool that can be charged in a non-contact state, a charging system that charges the battery pack, and a power tool including the battery pack.

  In power tools, cordless power tools that do not require a cord and are easy to handle even when used outdoors have become widespread. As a power source of the cordless electric tool, a secondary battery such as a nickel cadmium battery (hereinafter referred to as a nickel cadmium battery), a nickel metal hydride battery, or a lithium ion battery is used.

  When charging such a cordless power tool, most of the charging side such as the cordless power tool or the battery pack is charged by electrical contact with a charging device on the charging side by a metal contact. However, in working environments where electric tools are used, cutting scraps generated when cutting building materials, etc., and moisture, such as rain, are particularly likely to adhere to the metal contacts of the contact portion for electrical connection when outdoors. , Tend to cause contact failure. In addition, when charged objects generated by the human body come into contact with the metal contacts, the battery is protected from over-discharge and over-charge, etc., which are built into internal circuits such as lithium ion batteries in general. There is also a possibility that electrostatic breakdown may occur in a protection circuit or the like.

  Since the above is assumed when charging is performed using a metal contact, a non-contact charging method is also conceivable. For example, an electric tool has been proposed in which power is supplied in a non-contact state by a separation transformer between a charger and a battery pack and between the battery pack and a tool body (see, for example, Patent Document 1). ).

Japanese Patent Laying-Open No. 2005-73350 (page 4-5, FIG. 1)

  It is an object of the present invention to provide a battery pack that can be charged in a non-contact manner and that can stably drive an electric tool, a charging system that charges the battery pack, and an electric tool including the battery pack.

  Another object of the present invention is to enable charging of the battery pack while maintaining the connection state between the battery pack and the power tool.

In order to achieve the above object, the present invention provides a housing for accommodating battery cells and a side of the housing connected to a power tool, connected to a terminal of the power tool to supply discharge power and charge. A metal terminal connected to the apparatus and supplied with charging power, and a receiving coil provided on a side other than the side connected to the electric tool of the housing and receiving charging power from the power supply apparatus. A battery pack is provided.

In the battery pack described above, the housing has an upper part, a lower part located on the side facing the upper part, and a side part that is a part connecting the upper part and the lower part, It is preferable that the metal terminal is disposed on the upper side of the housing, and the power receiving coil is disposed on the lower side of the metal terminal.

Moreover, it is preferable to arrange | position the said receiving coil in the said lower side part side.

Moreover, it is preferable to arrange | position the said receiving coil in the said side part part side.

Moreover, it is preferable to provide the metal terminal on a substrate located between the battery cell and the upper portion.

Moreover, this invention provides the electric tool characterized by driving by supplying electric power from an above-described battery pack.

The present invention also provides a charging system comprising: the battery pack described above; and a charging device that is electrically connected to the battery pack and charges the battery pack.

According to the battery pack, the charging system for charging the battery pack, and the electric tool provided with the battery pack according to the present invention, the charging can be performed in a non-contact manner and in a contact state, and when the electric tool is driven, the contact state It is possible to achieve an excellent effect that it can be performed with

BRIEF DESCRIPTION OF THE DRAWINGS The schematic perspective view seen from the side of the electric tool by one embodiment of this invention, a battery pack, and an electric power supply apparatus. The perspective view from the upper part of the battery pack by this Embodiment. The perspective view of the battery pack and charging device by this Embodiment. The typical sectional view in the IV-IV section of Drawing 1 of the battery pack by this embodiment. The typical sectional view in the VV section of Drawing 1 of the battery pack by this embodiment. The block diagram which shows the battery pack and electric power supply apparatus by this Embodiment.

A battery pack, a charging system for charging the battery pack, and a power tool including the battery pack according to an embodiment of the present invention will be described with reference to FIGS. In the drawings, the top, bottom, front and back are determined as shown in each figure.

FIG. 1 is a diagram schematically illustrating a non-contact charging using the battery pack according to the present embodiment and a connection state with a power tool by a schematic perspective view. As shown in FIG. 1, the battery pack 200 according to the present embodiment drives the electric tool 100 by moving the electric power tool 100 such as an electric drill in the arrow A direction and electrically connecting it. Further, the battery pack 200 is charged by being fed by the power supply device 300.

As shown in FIGS. 1 to 3, the battery pack 200 includes an upper housing 220 and a lower housing 230 that are divided at a boundary portion 250, and a plurality of battery cells 202 are accommodated therein. In the example of FIG. 1, at least eight battery cells 202 are stored. These battery cells are connected to each other in a predetermined connection state to form a battery cell set and output predetermined power. The battery cell 202 is a secondary battery such as a lithium ion battery.

As shown in FIGS. 1 and 2, the upper housing 220 includes an upper part 226 and a side part 228. The upper part 226 is configured such that the front protrudes upward and the terminal 210 is disposed in the center part in the front-rear direction, and the rear part is formed below the front part side. The side surface portion 228 is formed so as to continuously surround the upper portion 226 in a substantially vertical direction, and forms a part of the side surface of the battery pack 200. An operation portion 223 is formed on a part of the side surface portion 228. The operation unit 223 is a member for releasing the engagement with the power tool or the like by pressing the battery pack 200 when the battery pack 200 is attached to or detached from the power tool or the like.

As shown in FIGS. 1 and 3, the lower housing 230 includes a lower part 224 and a side part 222. The lower side portion 224 forms the bottom surface of the lower housing 230. The side surface portion 222 is formed so as to continuously surround the lower side portion 224 in a substantially vertical direction, and forms a part of the side surface of the battery pack 200.

As shown in FIGS. 1 and 4, a substrate 208 is provided on the inner side of the upper portion 226 of the upper housing 220 and the lower housing 230 (also collectively referred to as housings 220 and 230). The substrate 208 is provided with a plurality of terminals 210 for electrical connection with external devices. For example, the terminal 210A can be a positive terminal connected to the positive side of the battery cell set, and the terminal 210B can be a negative terminal connected to the negative side of the battery cell set. The battery pack 200 supplies driving power to the electric power tool 100 via these terminals 210A and 210B, or is supplied with charging power when connected to a charging device.

Further, a charging circuit 250 for charging the battery cell 202 and a protection circuit 252 for preventing overcharge, overdischarge, overcurrent, etc. when the battery cell 202 is a lithium ion battery are mounted on the substrate 208. Yes. When the protection circuit 252 detects overcharge, overdischarge, overcurrent, or the like of the battery cell 202, the protection circuit 252 transmits a signal to the charge circuit 250 to stop charging, or to stop power supply to the connected power tool 1. To do.

As shown in FIGS. 1 and 5, the power receiving coil 240 is disposed between the lower side portion 224 inside the lower housing 230 and the battery cell 202. The power receiving coil 240 is connected to the charging circuit 252 of the substrate 208 through a wire 206 serving as a power feeding line. The power receiving coil 240 is supplied with electric power from the power supply device 300 by electromagnetic induction and receives power, thereby becoming a supply source of charging power for the battery cell 202. The wire 206 is inside the housings 220 and 230 and passes between the side portions 222 and 228 and the battery cell 202 to connect the power receiving coil 240 and the charging circuit 250.

As shown in FIG. 1, the electric power tool 100 connected to the battery pack 200 according to the present embodiment is an electric drill, for example, and includes a main body portion 102, a handle portion 106 formed to extend from the main body portion 102, and It has a drill bit 104 attached to the tip of the main body. A drive circuit 113 is formed inside the main body portion 102, and a motor 115 is provided inside the handle portion 106. A terminal 111 for electrical connection with the battery pack 200 is provided at the lower end of the handle portion 106. The power tool 100 is configured to be supplied with power by being connected to the battery pack 200 via the terminal 111, and to drive the drill bit 104 by driving the motor 115 by the drive circuit 113 to perform a predetermined work. Yes.

Next, electrical configurations and operations of the battery pack 200 and the power supply device 300 according to the present embodiment will be described with reference to FIGS. 1 and 6. As shown in FIGS. 1 and 6, the power supply device 300 includes a rectifier circuit 305, a high-frequency oscillation circuit 303, and a power supply coil 301, and is connected to a power source 307 such as a household commercial power source via the connection unit 303. It works by connecting.

The battery pack 200 serving as a charging unit includes a power receiving coil 240 that receives power, a charging circuit 250 that charges the battery cell 202 with the received power, and a plurality of battery cells 202. The charging circuit 250 includes a resonance capacitor 254 that transmits the power received by the power receiving coil, a smoothing circuit 256 that smoothes the power output from the resonance capacitor 254, a charging current according to the type and connection state of the battery cell 202, and the like. It has a charge control circuit 258 that controls the charging voltage and outputs the charging power.

An operation during charging of the power supply device 300 and the battery pack 200 configured as described above will be described. First, the power supply 307 and the power supply apparatus 300 are connected by the connection unit 303. The rectifier circuit 305 rectifies the AC power supplied from the power supply 307. The high-frequency oscillator circuit 303 converts the power rectified by the rectifier circuit 305 into a high-frequency voltage. An AC magnetic flux is generated in the feeding coil 301 by this high frequency voltage.

Due to this AC magnetic flux, an induced electromotive force is generated in the power receiving coil 240 of the battery pack 200 according to Faraday's law. The resonance capacitor 254 is configured to transmit more power by reducing the coupling impedance between the power supply device 300 on the power supply side and the battery pack 200 on the power reception side by resonance. . The induced electromotive force transmitted by the resonance capacitor 254 is smoothed by the smoothing circuit 256. The smoothed electric power is supplied to the charging control circuit 258, and charging is performed with a charging current and a charging voltage corresponding to the type and connection state of the battery cell 202. At this time, when the overcharge and overcurrent are detected by the protection circuit 252, the charging is stopped.

As described above, the battery pack 200 according to the present embodiment drives the electric power tool 100 by being connected to the electric power tool 100 via the terminal 210. Thus, since the electric tool 100 is driven by contact with a terminal, stable driving is possible.

By arranging the power feeding coil 301 of the power supply device 300 and the power receiving coil 240 of the battery pack 200 within a predetermined distance, power from a commercial power source or the like can be received via the power supply device 300. The battery pack 202 can charge the battery cell 202 by the received power. With such a configuration, electric power can be supplied in a non-contact manner, so that contact failure due to cutting waste or electrostatic breakdown due to charged materials or the like does not occur at a work site or the like. On the other hand, when it is desired to perform charging in a short time, the charging can be performed by connecting to an external charging device 10 via the terminal 210 and configuring the charging system 20 as shown in FIG. As described above, since charging can be performed by either contact or non-contact methods, the battery can be selectively used according to the situation, and a useful battery pack is obtained.

Further, the battery pack 200 has a protection circuit 252 and stops charging when an overcharge, overcurrent, or the like of the battery cell 202 is detected. When overdischarge is detected, power supply to the connected power tool 100 and the like is stopped. By including the protection circuit 252 as described above, it is possible to safely charge and drive the power tool.

Since the charging circuit 250 and the protection circuit 252 are mounted on the substrate 208 provided with the terminals 210, the space in the battery pack can be used efficiently, and the battery pack 200 does not increase in size. Since the wire 206 passes between the battery cell 202 and the housings 220 and 230, the wire 206 can be reliably electrically disconnected from the battery cell 202 and the outside.

Further, the battery pack 200 drives the electric power tool 100 by being connected to the electric power tool 100. However, since the board 208 and the power receiving coil 240 are provided on the opposing surfaces, the connection with the electric power tool 100 is continued. The battery can be charged by being placed on the power supply device 300 as shown in FIG.

The battery pack, the charging system for charging the battery pack, and the electric tool including the battery pack according to the present invention are not limited to the above-described embodiments, and various modifications and improvements can be made within the scope described in the claims. Is possible. For example, the power receiving coil 240 is provided between the lower side portion 224 of the housing 220 and the battery cell 202, but may be provided between the side surface portion 222 or the side surface portion 228 and the battery cell 202. At this time, the wire 206 connecting the substrate 208 and the power receiving coil 240 can be shortened, and there are effects such as noise prevention and short circuit prevention.

In the above embodiment, the housings 220 and 230 are divided and have a substantially rectangular parallelepiped shape with an unevenness on the upper portion. Any structure can be used as long as the terminal 210 can be installed and the substrate 208 and the power receiving coil 240 can be arranged at different locations.

The battery pack of the present invention, the charging system for charging the battery pack, and the electric tool provided with the battery pack can be used as a power source for electric equipment such as an electric tool, a charging system, and an electric tool.

DESCRIPTION OF SYMBOLS 100: Electric tool 200: Battery pack 202: Battery cell 206: Wire 208: Board | substrate 210: Terminal 220, 230: Housing 222, 228: Side part 224: Lower part 226: Upper part 250: Charging circuit 252: Protection circuit 240 : Power receiving coil 300: Power supply device 301: Power feeding coil

Claims (7)

A housing for accommodating the battery cells;
A metal terminal provided on a side of the housing connected to the electric tool, connected to a terminal of the electric tool to supply discharge power and connected to a charging device to supply charging power;
A receiving coil provided on a side other than the side connected to the electric tool of the housing, and receiving charging power from a power supply device;
A battery pack comprising: The housing has an upper part, a lower part located on the side facing the upper part, and a side part that connects the upper part and the lower part,
The battery pack according to claim 1, wherein the metal terminal is disposed on the upper side of the housing, and the power receiving coil is disposed on the lower side of the metal terminal. .   The battery pack according to claim 2, wherein the power receiving coil is disposed on the lower side portion side.   The battery pack according to claim 2, wherein the power reception coil is disposed on the side surface portion side.   The battery pack according to any one of claims 1 to 4, wherein the metal terminal is provided on a substrate positioned between the battery cell and the upper portion.   An electric tool that is driven by being supplied with electric power from the battery pack according to any one of claims 1 to 5. The battery pack according to any one of claims 1 to 5,
A charging device that is electrically connected to the battery pack and charges the battery pack;
A charging system comprising:

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