power tools

Abstract

To provide an electric power tool with an electric power tool power supply device capable of effectively utilizing each battery, where the electric power tool can be loaded with multiple batteries.SOLUTION: An electric power tool with an electric power tool power supply device comprises: a second voltage supply unit capable of supplying, based on a first power supply voltage supplied from a first battery, a second operating voltage for operating a second control unit, and capable of supplying, based on a second power supply voltage supplied from a second battery, a second operating voltage for operating the second control unit; a first voltage line configured to connect a first voltage supply unit and the second voltage supply unit and capable of supplying the first power supply voltage; a second voltage line configured to connect the first voltage supply unit and the second voltage supply unit and capable of supplying a second voltage lower than the first power supply voltage; and a backflow prevention circuit in the first voltage line capable of permitting a current to flow from the first voltage supply unit to the second voltage supply unit and capable of preventing a current from flowing from the second voltage supply unit to the first voltage supply unit.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a power tool. [Background technology]

[0002] 2. Description of the Related Art In recent years, power tools have become known that are more convenient to use by incorporating a wireless communication device in the power tool body.

[0003] Patent Document 1 discloses a power tool equipped with such a wireless communication device. This power tool includes an electric motor, a communication device for wireless communication, and a control unit for controlling the electric motor and the communication device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2017-064858 Summary of the Invention [Problem to be solved by the invention]

[0005] The power tool disclosed in Patent Document 1 has a problem in that the control unit controls the electric motor and the communication device, and therefore the control unit is affected by noise from the electric motor when communicating. In addition, the control unit must communicate while controlling the electric motor, and therefore cannot communicate in real time.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a power tool that is less susceptible to the effects of noise and that is capable of real-time communication. [Means for solving the problem]

[0007] The present application discloses a power tool including a power supply device for a power tool, the power supply device including a first control unit configured to control an electric motor mounted on the power tool with a first operating voltage based on a first power supply voltage supplied from a first battery, and a second control unit configured to control a communication device mounted on the power tool with a second operating voltage based on the first power supply voltage supplied from the first battery, and to control the communication device with the second operating voltage based on a second power supply voltage supplied from a second battery when the first power supply voltage is not supplied from the first battery, and the second control unit configured to execute a reset operation when a predetermined condition is satisfied.

[0008] The "power tool" of the present invention refers to a tool used for machining or other work that uses electricity as a power source. The "power tool" of the present invention includes not only a product used alone, but also a component or module that constitutes part of another device. For example, the "power tool" of the present invention may be a module that is attached to equipment such as a robot arm. The "power tool" of the present invention may also be a component that constitutes part of a machine tool with multiple functions. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a power tool according to one embodiment. [Figure 2] FIG. 2 is a cross-sectional view of a power tool according to one embodiment. [Figure 3] FIG. 3 is a block diagram showing the electrical circuit configuration of the power tool according to one embodiment. [Figure 4] FIG. 4 is a flowchart showing the operation of the power tool according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following embodiments of the present invention will be described with reference to the accompanying drawings. The following embodiments are merely examples for explaining the present invention, and are not intended to limit the present invention to these embodiments.

[0011] For convenience, the left-right direction on the paper in FIG. 2 will be referred to as the front-to-back direction X (an example of a "first direction"), and in particular the left direction on the paper will be referred to as the front X1 and the right direction on the paper will be referred to as the back X2. The up-down direction on the paper will be referred to as the up-down direction Z (an example of a "second direction"), and in particular the up direction on the paper will be referred to as the up Z1 and the down direction on the paper will be referred to as the down Z2. The direction perpendicular to the front-to-back direction X and the up-down direction Z will be referred to as the left-to-right direction Y (an example of a "third direction"), and in particular the right direction when facing forward X1 will be referred to as the right Y1 and the left direction will be referred to as the left Y2. These terms are used for the purpose of explaining relative directional relationships and do not indicate absolute directions.

[0012] An embodiment in which the present invention is applied to a reinforcing bar binding machine, which is a power tool, will be described below. Fig. 1 is a perspective view of a reinforcing bar binding machine 10, which is a power tool according to this embodiment, and Fig. 2 is a cross-sectional view of the reinforcing bar binding machine 10 taken along a plane perpendicular to the left-right direction Y.

[0013] However, the present invention is widely applicable to power tools that have communication capabilities and use an electric motor to perform work, such as drills, impact drivers, nailers, grinders, reciprocating saws, polishers, etc. The motor may be a brushless motor or a motor with a brush.

[0014] [Basic configuration of power tools]

[0015] The reinforcing bar binding machine 10 according to this embodiment is configured to be able to bind two or three or more reinforcing bars RB by feeding the wire W outward from the end of the front X1.

[0016] Specifically, the rebar tying machine 10 comprises a handle 10H for being held by an operator, a magazine 10M for storing the wire W, a wire feeding unit 12 for feeding the wire W outward from the front end X1, a curl forming unit 14 that forms a path of travel for the wire W for winding the wire W around the rebar RB, a cutting unit 16 for cutting the wire W wound around the rebar RB, a binding unit 18 for twisting the wire W wound around the rebar RB, a tool control unit including a drive control unit 22 for controlling a feed motor 12M and a binding motor 18M that are respectively equipped in the wire feeding unit 12 and the binding unit 18, and a communication unit 30 that comprises a communication device 32 for allowing the rebar tying machine 10 to communicate with external devices and a communication control unit 34 for controlling the communication device 32.

[0017] In the rebar tying machine 10 of this embodiment, the curl forming unit 14, cutting unit 16, tying unit 18, tool control unit, and communication unit 30 constitute the main body 10B of the rebar tying machine 10. The magazine 10M is provided extending downward Z2 from the lower part at the front X1 of the main body 10B. The handle 10H is provided extending downward Z2 from the lower part at the rear X2 of the main body 10B. Therefore, the magazine 10M is provided in front X1 of the handle 10H, and the handle 10H is provided in rear X2 of the magazine 10M. Furthermore, the lower part of the magazine 10M and the lower part of the handle 10H are connected. Each component will be described below.

[0018] The rebar binding machine 10 includes a handle 10H extending downward Z2 from the main body 10B. The handle 10H corresponds to the portion where an operator grips the rebar binding machine 10. The lower end of the handle 10H is formed so that a main battery 10BP can be detachably attached. A trigger 10HT is provided on the surface of the handle 10H facing forward X1. The rebar binding machine 10 is configured so that when an operator presses the trigger 10HT backward X2, the tool control unit starts a control operation as described below, and the binding operation begins.

[0019] The magazine 10M rotatably and detachably stores a reel RL around which a linear wire W is wound. The reel RL is configured to be able to simultaneously feed out one or more wires W. The wire W is a linear body suitable for bundling long, flexible metal wires (including coated wires) and other reinforcing bars RB.

[0020] The wire feeding unit 12 includes a pair of gears 12G configured to rotate in opposite directions while sandwiching the wire W, thereby allowing the wire W to advance, and a feed motor 12M (an example of an "electric motor") that drives the gears 12G. The feed motor 12M includes a rotor and a stator. The wire feeding unit 12 is configured to feed the wire W outward by rotating the rotor of the feed motor 12M in the forward direction, and to retract the wire W by rotating the rotor in the reverse direction. A tool control unit that controls the feed motor 12M of the wire feeding unit 12 will be described later.

[0021] The curl forming unit 14 includes a curl guide 14A that bends the wire W fed by the wire feeding unit 12 to form a curl, and an induction guide 14B that guides the wire W that has been curled by the curl guide 14A to the bundling unit 18. The curl guide 14A is configured to be able to curve the wire W into a loop by advancing the wire W along its inner wall surface. Therefore, by feeding the wire W in a state where multiple reinforcing bars RB are arranged in the space between the curl guide 14A and the induction guide 14B so that they extend in the left-right direction Y, it is possible to wind the wire W around the reinforcing bars RB.

[0022] The cutting unit 16 includes a fixed blade, a movable blade that cuts the wire W in cooperation with the fixed blade, and a transmission mechanism 16A that transmits the operation of the binding unit 18 to the movable blade. The cutting unit 16 is configured to be able to cut the wire W by the rotational operation of the movable blade with the fixed blade as a fulcrum axis. The transmission mechanism 16A is configured to transmit the operation of the binding unit 18 to the movable blade and to rotate the movable blade in conjunction with the binding operation of the binding unit 18. Therefore, the transmission mechanism 16A is configured to be able to cut the wire W at a predetermined timing, as described below, by rotating the movable blade in conjunction with the operation of the binding unit 18.

[0023] The binding unit 18 includes a pair of hooks 18H configured to be openable and closable to clamp the wire W, a rotating shaft for rotating the pair of hooks 18H around the forward / backward direction X as the rotation axis, a reducer for moving the rotating shaft in the rotation axis direction (forward / backward direction X) and rotating the rotating shaft that has moved forward X1, and a binding motor 18M configured to be rotatable around the rotation axis AX.

[0024] The rotating shaft of the bundling unit 18 rotates in the forward direction when the bundling motor 18M rotates in the forward direction. A sliding member is provided around the rotating shaft, and the sliding member is configured to move forward in the X1 direction when the rotating shaft rotates in the forward direction. When the pair of hooks 18H is in an open state, the wire W fed by the feed motor 12M advances while curving along the inner wall surfaces of the curl guide 14A and the induction guide 14B, and the tip of the wire W passes through the gap between the pair of hooks 18H, which are open. When the bundling motor 18M rotates in the forward direction and the rotating shaft rotates in the forward direction in this state, the sliding member moves forward in the X1 direction, and the pair of hooks 18H close. Therefore, the pair of hooks 18H are configured to be able to clamp the wire W. When the bundling motor 18M further rotates in the forward direction and the rotating shaft rotates in the forward direction, the sliding member moves forward in the X1 direction, and the transmission mechanism 16A rotates the movable blade to cut the wire W. When the bundling motor 18M further rotates in the forward direction, the bundling unit 18 bends the tip of the cut wire W with the pair of hooks 18H clamping the wire W. When the bundling motor 18M further rotates in the forward direction, the rotating shaft rotates together with the sliding unit around the rotation axis in the front-rear direction X. When the pair of hooks 18H clamp the wire W, the pair of hooks 18H are configured to twist the wire W by rotating the rotating shaft.

[0025] [Electric circuit configuration of power tools] 3 is a block diagram showing the electrical circuit configuration of the reinforcing bar binding machine 10 according to this embodiment. Of the electrical circuit configuration of the reinforcing bar binding machine 10, the configuration for controlling the feed motor 12M, the configuration for controlling the communication device 32, and the configuration for supplying power (voltage) to these components constitute the power supply device 40 of this embodiment.

[0026] Specifically, the power supply device 40 of this embodiment includes a battery connection unit 40CN for receiving power (voltage) from a battery 10BP (sometimes referred to as a "driving battery" or "first battery"), a power switch 40S for turning on and off the supply of power (voltage) supplied from the battery connection unit 40CN, a first power control unit 41PC (an example of a "first voltage supply unit") that receives power (voltage) from the battery 10BP via the power switch 40S and supplies a first operating voltage for operating a drive control unit 22 (an example of a "first control unit") based on the first power supply voltage supplied from the battery 10BP, a drive control unit 22 that operates based on the first operating voltage and generates a control signal for controlling the feed motor 12M, and a motor control unit 24 that controls the current flowing through the stator of the feed motor 12M based on the control signal generated by the drive control unit 22.

[0027] Battery 10BP is configured to be capable of supplying power for operating at least drive control unit 22, motor control unit 24, feed motor 12M, binding motor 18M, communication control unit 34, wireless communication device 32, and position information acquisition unit 36 ​​(described later). Battery 10BP is, for example, a rechargeable lithium-ion secondary battery with a predetermined rated capacity, rated voltage, and rated current. For example, battery 10BP has a rated capacity of 5.0 Ah and is configured to be capable of supplying a rated DC voltage of 14.4 V. However, as described later, the DC voltage supplied from battery 10BP gradually decreases as power is consumed by battery 10BP.

[0028] The battery connector 40CN receives a DC voltage from the battery 10BP and supplies it to the first power control unit 41PC. The power supply device 40 includes a first voltage line 41 that connects the battery connector 40CN and the first power control unit 41PC, and the first DC power supply voltage supplied from the battery 10BP is applied to this first voltage line 41.

[0029] The power switch 40S turns on or off the supply of power (voltage) supplied from the battery 10BP to the first power control unit 41PC via the battery connection unit 40CN in accordance with the operation of the main power switch (not shown) of the rebar binding machine 10. Therefore, when the operator turns off the main power switch, the power switch 40S cuts off (turns off) the supply of power (voltage) from the battery 10BP to the first power control unit 41PC, and when the operator turns it on, the power switch 40S permits (turns on) the supply of power (voltage) from the battery 10BP to the first power control unit 41PC.

[0030] The first power control unit 41PC generates a voltage for operating each circuit element, including the drive control unit 22, based on the first power supply voltage supplied from the battery 10BP, and supplies the generated voltage to each circuit element. For example, the first power control unit 41PC generates a voltage of 3.3 V (an example of a "first operating voltage"), which is the operating voltage of the drive control unit 22, based on the first power supply voltage of 14.4 V supplied from the battery 10BP, and supplies the voltage to the drive control unit 22. The first power control unit 41PC is also configured to supply the first power supply voltage (14.4 V) as is to the motor control units 24 and 26 and the stators of each motor. Here, supplying a voltage includes generating and supplying a voltage and passing through and supplying a voltage as is without generating it. The first power control unit 41PC is further configured to generate an intermediate voltage that is higher than the first operating voltage but lower than the first power supply voltage, and supply the intermediate voltage to different circuit elements. The first power control unit 41PC may also include a booster circuit that generates a voltage higher than the first power supply voltage and supplies the voltage to different circuit elements.

[0031] The drive control unit 22 operates based on a voltage of, for example, 3.3 V, generates a control signal for controlling the feed motor 12M, and supplies the control signal to the motor control unit 24. The drive control unit 22 is also configured to be able to control other actuators of the rebar binding machine 10. The drive control unit 22 also supplies the first power supply voltage supplied from the first power control unit 41PC to the motor control unit 24 (for example, to the positive power supply line of the motor control unit 24). The drive control unit 22 is further configured to receive a signal detecting that the trigger 10HT has been pressed, and to start a motor control operation based on this signal. In addition, the drive control unit 22 may be configured to receive a signal indicating the temperature of the power tool (rebar binding machine 10) from a thermistor, and to control the feed motor 12M based on this signal. For example, the drive control unit 22 may generate different control signals and supply them to the motor control unit 24 when the power tool is relatively high and when it is relatively low.

[0032] The drive control unit 22 may be composed of a single or multiple processors implemented by an integrated circuit (IC) and a memory (including a non-volatile semiconductor memory that stores information non-transitory) that stores firmware including computer instructions that are executed by the processor and perform the processes described in this embodiment. The drive control unit 22 may also be implemented by an IC called an ASIC, FPGA, microcontroller, etc. The drive control unit 22 also functions as part of the tool control unit. The motor control unit 24 controls the current flowing through the stator of the feed motor 12M based on the control signal generated by the drive control unit 22. For example, the motor control unit 24 may include a plurality of (e.g., six) semiconductor elements connected in a three-phase bridge configuration between a positive power supply line and a negative power supply line of ground (reference potential), and a driver circuit for generating and supplying a gate signal (or base signal) to the gate (or base) of each semiconductor element.

[0033] The feed motor 12M, which is an electric motor in this embodiment, includes, for example, a stator made up of three-phase windings connected to three-phase outputs of the motor control unit 24, and a rotor configured to be rotatable in either the forward or reverse direction in accordance with a rotating magnetic field generated by current flowing through the stator windings. The feed motor 12M may further include, for example, a Hall element for detecting the position of the rotor, and the drive control unit 22 may be configured to receive a position signal from the Hall element and generate a control signal based on the signal.

[0034] Similarly, the power supply device 40 also includes a drive control unit for the bundling motor 18M that generates a control signal for controlling the bundling motor 18M and supplies it to the motor control unit 26 of the bundling motor 18M, and a motor control unit 26 that controls the current flowing through the stator of the bundling motor 18M based on the control signal generated by the drive control unit (detailed description will be omitted).The drive control unit for the bundling motor 18M and the drive control unit 22 for the feed motor 12M may be configured to be provided on the same semiconductor chip.

[0035] The power supply device 40 further includes a first wiring board 41PCB on which at least a first power control unit 41PC, a drive control unit 22, a motor control unit 24, and a motor control unit 26 are mounted. The first wiring board 41PCB is provided with a first connection portion 41CN (an example of a "first connector") for connection to a second wiring board 42PCB (described later) via a cable 40CB. As shown in FIG. 3, the first voltage line 41 includes a first wiring portion 41A that connects the battery connection portion 40CN and the first power control unit 41PC, and a second wiring portion 41B that branches from the first wiring portion 41A and connects to the first connection portion 41CN. The power supply device 40 further includes a second voltage line 42 that is configured to be able to apply a first operating voltage (3.3V) generated by the first power control unit 41PC and connects the first power control unit 41PC and the first connection portion 41CN. In Figure 3, the first wiring board 41PCB is drawn conceptually, but the actual first wiring board 41PCB is formed in a rectangular shape having two parallel long sides and two parallel short sides connecting the ends of the long sides.

[0036] The above-described configuration enables the supply of power to realize the functions of the power tool. Next, the configuration relating to the communication function of the power tool will be described.

[0037] As also shown in FIG. 3, the power supply device 40 includes a second battery 42BP for communication (sometimes referred to as a "communication battery"), a second power control unit 42PC (an example of a "second voltage supply unit") that is configured to be able to supply a second operating voltage for operating the communication control unit 34 (an example of a "second control unit") based on a first power supply voltage supplied from the main battery 10BP, and that is configured to be able to supply a second operating voltage for operating the communication control unit 34 based on the second power supply voltage supplied from the second battery 42BP when the main battery 10BP is removed, etc., and a communication control unit 34 that controls the wireless communication device 32 (an example of a "communication device 32") and the location information acquisition unit 36 ​​based on the second operating voltage supplied from the second power control unit 42PC.

[0038] The power tool further includes a communication unit 30 including a position information acquisition unit 36 ​​that acquires position information of the power tool and supplies it to a communication control unit 34, and a wireless communication device 32 for wirelessly transmitting and receiving information to and from external devices.

[0039] The position information acquisition unit 36 ​​includes, for example, an antenna configured to receive signals from GPS (or GLONASS or other GNSS) positioning satellites, and a receiving circuit that acquires position information of the power tool based on the signals received by the antenna.

[0040] The wireless communication device 32 includes, for example, an antenna configured to be able to transmit and receive information to and from a remote base station based on a predetermined standard using a frequency band in a licensed or unlicensed band based on LPWA technology, an RFIC that demodulates an analog signal received by the antenna and supplies it to a baseband IC, and modulates the signal supplied from the baseband IC into an analog signal and transmits it from the antenna, and a baseband IC that decodes and encodes the signal obtained from the RFIC in accordance with a protocol defined in the standard to transmit and receive information. Note that the communication device 32 may be compatible with a short-range wireless communication method such as Bluetooth (registered trademark) or wireless LAN.

[0041] With the above-described configuration, the communication control unit 34 is configured to provide the position information of the power tool to an external device, for example, by transmitting the position information acquired by the position information acquisition unit 36 ​​via the wireless communication unit 30. In this embodiment, the communication control unit 34, the RFIC, and the baseband IC may be stacked in the same semiconductor package. Alternatively, the communication control unit 34 and the baseband IC may be formed on the same semiconductor chip.

[0042] The power supply device 40 further includes a second wiring board 42PCB on which at least the second power control unit 42PC, the communication control unit 34, the communicator 32, and the position information acquisition unit 36 ​​are mounted. The second wiring board 42PCB is provided with a second connection portion 42CN (an example of a "second connector") for connection to the first wiring board 41PCB via a cable 40CB. As shown in FIG. 3, the first wiring portion 41A and the second wiring portion 41B of the first voltage line 41 are formed on the first wiring board 41PCB, while the third wiring portion 41C electrically connected to the first wiring portion 41A and the second wiring portion 41B via a connector is formed on the second wiring board 42PCB. Furthermore, the wiring portion connecting the first connection portion 41CN of the second voltage line 42 to the first power control unit 41PC is formed on the first wiring board 41PCB, while the wiring portion electrically connected to this wiring portion via a connector and connected to the second power control unit 42PC is formed on the second wiring board 42PCB.

[0043] The power supply device 40 further includes a second battery 42BP, which supplies power for operating at least the communication control unit 34, the wireless communication device 32, and the position information acquisition unit 36. The second battery 42BP is, for example, a rechargeable lithium-ion secondary battery having a predetermined rated capacity, rated voltage, and rated current. For example, the second battery 42BP has a rated capacity smaller than that of the main battery 10BP and is configured to supply a DC voltage rated at 3.6 V (an example of a "second power supply voltage"). In addition, since the second battery 42BP is housed within a housing constituting the power tool body 10B, unlike the main battery 10BP, it is not easily detachable and is instead integrally fixed to the second wiring board 42PCB. Note that the second battery 42BP does not have to be integrally fixed to the second wiring board 42PCB; for example, it may be detachable from the second wiring board 42PCB.

[0044] The second power control unit 42PC is configured to be able to generate a voltage for operating each circuit element including the communication control unit 34 and the drive control unit 22 based on the power supply voltage supplied from the battery 10BP and supply the generated voltage to each circuit element, etc. For example, the second power control unit 42PC generates a voltage of 3.3 V (an example of a "second operating voltage") that is the operating voltage of the communication control unit 34 based on the power supply voltage of 14.4 V supplied from the battery 10BP and supplies the voltage to the communication control unit 34 via a third voltage line 43 that connects the second power control unit 42PC and the communication control unit 34. Similarly, the second power control unit 42PC generates a predetermined operating voltage and supplies it to the position information acquisition unit 36 ​​and the wireless communication unit 30.

[0045] Additionally, the second power control unit 42PC is configured to generate an operating voltage for operating each circuit element, etc., based on a DC voltage of 3.6 V, equivalent to the second power supply voltage, supplied from the second battery 42BP, and supply the operating voltage to each circuit element, etc., including the communication control unit 34 and the drive control unit 22. Here, the second power control unit 42PC includes a boost circuit capable of generating a voltage higher than the second power supply voltage to operate the antenna. However, the rebar binding machine 10 does not necessarily have to include a boost circuit. In this embodiment, because the operating voltage of the antenna is higher than the second power supply voltage, the rebar binding machine 10 includes a boost circuit such as a charge pump circuit. However, for example, if the circuit elements are selected so that the operating voltage of the circuit elements driven by power from the second battery 42BP is equal to or lower than the second power supply voltage, or if the second power supply voltage is set, the rebar binding machine 10 does not necessarily have to include a boost circuit.

[0046] With the above-described configuration, when the main battery 10BP is removed, the second power control unit 42PC is configured to operate the drive control unit 22, the communication control unit 34, the position information acquisition unit 36, and the wireless communication unit 30 based on the second power supply voltage supplied from the second battery 42BP, thereby enabling wireless transmission and reception of information with an external device. Therefore, even when the main battery 10BP is removed, the communication control unit 34 is configured to provide the external device with position information of the power tool by transmitting the position information acquired by the position information acquisition unit 36 ​​via the wireless communication unit 30, and is also configured to store update data for updating the firmware of the drive control unit 22, received via the wireless communication unit 30, in, for example, a nonvolatile semiconductor memory constituting the drive control unit 22.

[0047] Furthermore, the second power control unit 42PC is configured to generate a charging voltage for charging the second battery 42BP based on the power supply voltage supplied from the main battery 10BP, and to charge the second battery 42BP. Therefore, the power supply device 40 according to this embodiment is configured to operate the drive control unit 22, motor control unit 24, motor control unit 26, motors (feed motor 12M and bundling motor 18M), communication control unit 34, position information acquisition unit 36, and wireless communication unit 30 based on the power supplied from the battery 10BP when the battery 10BP is attached, and to charge the second battery 42BP, and is configured to operate the drive control unit 22, communication control unit 34, position information acquisition unit 36, and wireless communication unit 30 based on the power supplied from the second battery 42BP when the main battery 10BP is removed. As mentioned above, supplying a voltage includes passing it through without generating it and supplying it as is, so the power supply voltage may be supplied to the communication control unit 34, etc. by directly connecting the wiring to which the output voltage from the second battery 42BP is applied to the power supply terminal of the communication control unit 34, etc., or the power supply voltage may be supplied to the drive control unit 22, etc. by directly connecting the wiring to which the output voltage from the second power control unit 42PC is applied to the power supply terminal of the drive control unit 22, etc.

[0048] The power supply device 40 further includes a second wiring board 42PCB on which at least a second power control unit 42PC, a communication control unit 34, a position information acquisition unit 36, and a wireless communication unit 30 are mounted. The second wiring board 42PCB is provided with a second connection unit 42CN (an example of a "second connector") for connecting to the first wiring board 41PCB via a cable 40CB.

[0049] As shown in FIG. 3, the first voltage line 41 to which the power supply voltage from the battery 10BP is applied not only supplies voltage to the first power control unit 41PC via the power switch 40S, but also supplies voltage to the second power control unit 42PC by having wiring that connects to the second power control unit 42PC via the first connection portion 41CN of the first wiring board 41PCB, the cable 40CB, and the second connection portion 42CN of the second wiring board 42PCB.

[0050] Furthermore, the second voltage line 42 to which the first operating voltage (3.3V) generated by the first power control unit 41PC is applied has a wiring section connected to the second power control unit 42PC and the communication control unit 34 via a connection section of the first wiring board 41PCB, the cable 40CB, and a connection section of the second wiring board 42PCB, so that when the main battery 10BP is attached, it is configured to be able to supply power (voltage and current) in the direction from the first power control unit 41PC to the second power control unit 42PC, and when the main battery 10BP is removed, it is configured to be able to supply power (voltage and current) in the direction from the second power control unit 42PC to the first power control unit 41PC.

[0051] Here, the third wiring portion 41C of the first voltage line 41 provided on the second wiring board 42PCB is provided with, as a circuit configured to allow a current to flow from the first power control unit 41PC to the second power control unit 42PC and to prevent a current from flowing from the second power control unit 42PC to the first power control unit 41PC, for example, a diode (an example of a "backflow prevention circuit") having an anode connected to the first power control unit 41PC side and a cathode connected to the second power control unit 42PC. Note that the backflow prevention circuit may be provided in the second wiring portion 41B of the first voltage line 41 provided on the first wiring board 41PCB.

[0052] By providing a backflow prevention circuit, it is possible to prevent current from flowing from the second battery 42BP to the first power control unit 41PC via the second power control unit 42PC, thereby making it possible to effectively utilize the main battery 10BP and the second battery 42BP.

[0053] It is preferable that the second voltage line 42 is configured to be capable of allowing current to flow from the first power control unit 41PC (first voltage supply unit) to the second power control unit 42PC (second voltage supply unit), and to be capable of allowing current to flow from the second power control unit 42PC (second voltage supply unit) to the first power control unit 41PC (first voltage supply unit).

[0054] With this configuration, it is possible to supply power (voltage) to the power terminal of the drive control unit 22 of the first wiring board 41PCB via the second voltage line 42 that connects the second wiring board 42PCB, which is a communication board, the second connector, the first connector, and the first power control unit 41PC.

[0055] This allows the drive control unit 22 to operate even when the main battery 10BP is removed. For example, the drive control unit 22 can update firmware, which is a control program. This reduces the need for an operator to interrupt work in order to update firmware for the drive control unit 22, thereby improving work efficiency.

[0056] The second voltage line 42 may be provided to connect the first connector and the power supply terminal of the drive control unit 22 of the first wiring board 41PC directly without going through the first power control unit 41PC. Additionally, the power supply device 40 according to this embodiment is configured to connect the first wiring board 41PCB and the second wiring board 42PCB via a cable 40CB (including wiring that forms part of the first voltage line 41 and wiring that forms part of the second voltage line 42). This allows the first wiring board 41PCB and the second wiring board 42PCB to be located in different positions. For example, the first wiring board 41PCB may be located above the motor 18M (Z1) so that the board is substantially perpendicular to the vertical direction Z, and the second wiring board 42PCB may be located to the left and right of the motor 18M (e.g., to the right Y1) so that the board is substantially perpendicular to the horizontal direction Y. This configuration allows the two wiring boards to be located substantially perpendicular to each other and surround the motor (either the motor 18M or the feed motor 12M). Here, the two wiring boards may be arranged so that the distance between the rotation axis of the motor (e.g., bundled motor 18M) (e.g., rotation axis AX of bundled motor 18M) and second wiring board 42PCB is greater than the distance between the rotation axis of the motor and first wiring board 41PCB. This configuration allows second wiring board 42PCB to be arranged farther from the motor than first wiring board 41PCB, reducing the possibility that noise associated with motor rotation will adversely affect communication, and allows first wiring board 41PCB to be arranged closer to the motor than second wiring board 42PCB, making it possible to reduce the distance between motor control unit 24 (or motor control unit 26) and the stator of the motor.

[0057] The power supply device further includes a drive control unit 22 mounted on the first wiring board 41PCB to control the feed motor 12M and the binding motor 18M, which are the electric motors of the power tool 10, and a communication control unit 34 mounted on the second wiring board 42PCB to control the communicator 32. With this configuration, the power tool allows the communication control unit 34 to perform wireless communication simultaneously and in parallel with the drive control unit 22 controlling the electric motors. This allows the communication control unit 34 to provide operational information, positional information, and the like of the power tool to an external device in real time. Furthermore, communication by the communication control unit 34 does not interfere with the control of the electric motors by the drive control unit 22.

[0058] The inventors of the present application have noticed that providing the drive control unit 22 and the communication control unit 34 on separate chips may cause the communication control unit 34 to become uncontrollable.

[0059] That is, the communication control unit 34 is configured to be operable based on the second power supply voltage supplied from the second battery 42BP even when the main battery 10BP is removed, and the second battery 42BP is configured to be chargeable when the main battery 10BP is attached, so the communication control unit 34 is always operable. For this reason, even if the communication control unit 34 falls into an uncontrollable state, the communication control unit 34 cannot be reset by turning the power switch 40 on or off.

[0060] Therefore, the communication control unit 34 of the present application is configured to actively execute a reset operation when a predetermined condition is satisfied.

[0061] Specifically, the drive control unit 22 is configured to be able to transmit a predetermined signal to the communication control unit 34, and the communication control unit 34 is configured to be able to transmit a predetermined response signal to the drive control unit 22 when it receives the predetermined signal from the drive control unit 22. Furthermore, after transmitting the predetermined signal to the communication control unit 34, if the drive control unit 22 does not receive the predetermined response signal from the communication control unit 34 within a predetermined period of time, it is configured to transmit a reset signal to the communication control unit 34 to cause the communication control unit 34 to perform a reset operation.

[0062] With this configuration, it becomes possible for the drive control unit 22 to determine that the communication control unit 34 has fallen into an uncontrollable state based on the fact that the drive control unit 22 does not receive a response signal to a predetermined signal from the communication control unit 34. Furthermore, the drive control unit 22 can send a reset signal to the communication control unit 34 that has fallen into an uncontrollable state, thereby enabling the communication control unit 34 to perform a reset operation.

[0063] [Rebar binding machine operation] The following describes the operation of the reinforcing bar binding machine 10. As described above, this embodiment can be applied to power tools other than the reinforcing bar binding machine 10.

[0064] FIG. 4 is a flowchart showing the reset operation of the reinforcing bar binding machine 10. First, the drive control unit 22 determines whether power is being supplied from the main battery 10BP (step S10). When the worker attaches the main battery 10BP to the bottom end of the handle 10H and turns on the main power switch, the drive control unit 22 determines that power is being supplied from the main battery 10BP (YES). The rebar binding machine 10 is in a state where it can perform work. When predetermined conditions are satisfied in this state, the drive control unit 22 is configured to be able to perform a handshake with the communication control unit 34 (step S12).

[0065] When the rebar binding machine 10 is in a state where it can perform work, a DC voltage from the first battery is applied to the first voltage line 41, so that the first voltage line 41 is at 14.4 V. When the operator presses the trigger 10HT in this state, the drive control unit 22 starts drive control of the motors (binding motor 18M and feed motor 12M).

[0066] When the rebar binding machine 10 is in a state where it can perform work, the main battery 10BP simultaneously supplies power to the communication unit 30. Specifically, the first power supply unit is configured to generate an operating voltage of 3.3 V for the communication control unit 34 based on a DC voltage of 14.4 V, which corresponds to the first power supply voltage, supplied from the battery 10BP, and supply this voltage to the communication control unit 34 via the second voltage line 42. Therefore, the communication control unit 34 starts controlling the communication device 32. For example, the communication control unit 34 transmits the position information acquired by the position information acquisition unit 36 ​​from the antenna of the communication device 32 to an external device, thereby transmitting the position information of the rebar binding machine 10 to the external device, and also transmits operation information of the rebar binding machine 10 received from the drive control unit 22 to the external device.

[0067] In this way, the rebar binding machine 10 is configured to be able to execute drive control of the motor and control of the communication device in parallel. In this case, the drive control unit 22 and the communication control unit 34 are mounted on different wiring boards and are separated from each other, so the communication device 32 can communicate while suppressing the effects of noise and the like that accompanies the rotation of the motor.

[0068] On the other hand, when work is completed, the worker removes the main battery 10BP from the bottom end of the handle 10H or turns off the power switch 40. When the main battery 10BP is removed or the power switch 40S is turned off, the electric motors (feed motor 12M and binding motor 18M) of the rebar binding machine 10 are not operating and are in a non-operating state. At this time, the drive control unit 22 determines that power is not being supplied from the main battery 10BP (NO) and then determines whether power is being supplied from the sub-second battery 42BP (step S14). If the drive control unit 22 determines that power is being supplied from the sub-second battery 42BP (YES), the communicator 32 of the rebar binding machine 10 is in a state where it can communicate using the sub-second battery 42BP as its power source. In this state, if a predetermined condition is satisfied, the drive control unit 22 is configured to be able to execute a handshake with the communication control unit 34 (step S12). In other words, the drive control unit 22 is configured to be able to perform a reset operation when predetermined conditions are satisfied, whether the rebar binding machine 10 is capable of operation and is receiving power from the main battery 10BP, or whether the rebar binding machine 10 is capable of communication and is receiving power from the sub second battery 42BP. On the other hand, if the drive control unit 22 determines that power is not being supplied from the sub second battery 42BP (NO), the reset signal is not transmitted (step S16).

[0069] Next, a handshake operation is initiated to determine whether a reset operation is necessary. Specifically, the second power control unit 42PC applies the operating voltage (3.3 V) of the drive control unit 22 to the second voltage line 42 based on the first power supply voltage (operable state) or the second power supply voltage (communication available state) supplied from the battery 10BP (operable state) or the second battery 42BP (communication available state), thereby supplying power to the drive control unit 22 (step S20). At the same time, the second power control unit 42PC applies the operating voltage (3.3 V) of the communication control unit 34 to the third voltage line 43 based on the first power supply voltage (operable state) or the second power supply voltage (communication available state) supplied from the battery 10BP (operable state) or the second battery 42BP (communication available state). Similarly, the second power control unit 42PC generates operating voltages for operating each circuit element, such as the antenna of the communication unit 30, and supplies the operating voltages to each circuit element, including the communication control unit 34 and the drive control unit 22. Even when communication is possible, power is supplied from the second battery 42BP to the drive control unit 22, which is a circuit element on the first wiring board 41PCB, so the drive control unit 22 is configured to be operable together with the communication unit 30. The rebar binding machine 10 may be configured to perform a handshake operation to determine whether a reset operation is necessary, for example, when a predetermined time arrives (an example of "when a predetermined condition is satisfied").

[0070] Next, the drive control unit 22 transmits a predetermined signal to the communication control unit 34. Then, the drive control unit 22 determines whether or not a predetermined response signal has been received from the communication control unit 34 within a predetermined time (step S18).

[0071] If the drive control unit 22 receives a predetermined response signal from the communication control unit 34 within a predetermined time (YES), it is determined that the communication control unit 34 is not in an uncontrollable state, and the handshake operation ends (step S20). Thereafter, the communication control unit 34 may be configured to start communication.

[0072] On the other hand, if the drive control unit 22 does not receive a specified response signal from the communication control unit 34 within a specified time (NO), it is determined that the communication control unit 34 has fallen into an uncontrollable state, and the drive control unit 22 sends a reset command to the communication control unit 34 to perform a reset operation (step S22).

[0073] The communication control unit 34 receives the reset command and executes the reset operation (step S24).

[0074] As described above, according to this embodiment, it is possible to provide a power supply device for a power tool and a power tool that are less susceptible to the influence of noise and are capable of real-time communication.

[0075] It is also possible to prevent the communication control unit from unintentionally falling into an uncontrollable state. Furthermore, since the system is configured to execute an operation (for example, a handshake operation) using the sub-battery to determine whether a reset operation is necessary after the main battery is removed, the system does not interfere with the work of the operator.

[0076] This embodiment can be modified in various ways. For example, the communication control unit 34 may be configured to execute a reset operation when at least one of the following conditions is further satisfied:

[0077] Condition 1 is that the number of operations of the power tool (e.g., the number of bundling operations) or the number of times the trigger (e.g., trigger 10HT) is pressed is equal to or greater than a predetermined threshold. For example, the drive control unit 22 may be configured to be able to count at least one of the number of bundling operations by the rebar binding machine 10 or the number of times the trigger is pressed, and may be configured to be able to send a reset command to the communication control unit 34 when the number of bundling operations or the number of times the trigger is pressed is equal to or greater than a predetermined threshold.

[0078] Condition 2 is that a trigger (for example, trigger 10HT) is not pressed. The drive control unit 22 may be configured to be able to send a reset command to the communication control unit 34 when the trigger 10HT is not pressed (including within a predetermined time after the trigger 10HT is pressed).

[0079] Condition 3 is that the number or amount of data of the power tool operation information stored in the memory is equal to or greater than a predetermined threshold. As described above, the drive control unit 22 includes a volatile or non-volatile memory. Therefore, the drive control unit 22 may be configured to transmit a reset command to the communication control unit 34 when the number or amount of data of the power tool operation information stored in the memory is equal to or greater than a predetermined threshold.

[0080] Condition 4 is that all or part of the consumables (e.g., wire) used by the power tool have been used up. For example, the drive control unit 22 may be configured to be able to detect the amount of consumables (remaining amount of wire W) loaded in the rebar binding machine 10, and the drive control unit 22 may be configured to be able to send a reset command to the communication control unit 34 when all of the consumables have been used up.

[0081] Condition 5 is that an operational error has occurred in the power tool. For example, the rebar binding machine 10 is configured to be able to detect an error in which the desired curl cannot be formed by the curl guide 14A or the induction guide 14B. Therefore, for example, the drive control unit 22 may be configured to be able to send a reset command to the communication control unit 34 when an operational error is detected.

[0082] Condition 6 is that the operating conditions of the power tool have changed. For example, the rebar binding machine 10 is equipped with a torque adjustment unit for changing the binding force. Therefore, for example, the drive control unit 22 may be configured to be able to send a reset command to the communication control unit 34 when the operating conditions of the power tool have changed (when the binding force has changed due to torque adjustment).

[0083] Condition 7 is that the power tool is turned off due to inactivity for a certain period of time. For example, the rebar binding machine 10 may be configured so that the power switch 40S automatically turns off when the power tool is not operated for a certain period of time. In this case, the drive control unit 22 may be configured to be able to send a reset command to the communication control unit 34 when the power tool is turned off due to inactivity for a certain period of time.

[0084] Condition 8 is that the main battery 10BP does not supply power. The drive control unit 22 may be configured to be able to send a reset command to the communication control unit 34 when the main battery 10BP is removed or when the main battery 10BP is attached but does not supply power because it has no remaining power.

[0085] [Variation 1] Modifications of the above-described embodiment will be described below. Elements and effects that exhibit the same or similar configurations or functions as those of the above-described embodiment will be given the same reference numerals or names, and descriptions will be omitted or simplified as appropriate, with the focus on differences. The above-described embodiment and these modifications can be further modified within the scope of the ordinary creative ability of a person skilled in the art.

[0086] In the above embodiment, the communication control unit 34 is configured to be able to execute the reset operation by receiving a reset command from the drive control unit 22. In the power tool according to this modification, the communication device 32 is configured to receive a reset command transmitted by an external device, and the communication control unit 34 is configured to be able to execute the reset operation based on the reset command received by the communication device 32.

[0087] For example, the external device may be configured to send a reset command to the power tool at a time when no work is being performed (e.g., 2:00 a.m.) The communicator 32 may be configured to receive the reset command from the external device after the main battery is removed, and the communication control unit 34 may be configured to perform a reset operation based on the reset command received by the communicator 32.

[0088] The above configuration also makes it possible to prevent the communication control unit from unintentionally falling into an uncontrollable state. Furthermore, since the communication device 32 is configured to receive the reset command at a time when no work is being performed, it does not interfere with the work of the worker.

[0089] [Variation 2] The power tool according to this modification includes a reset button and a reset circuit. When an operator presses the reset button, the reset circuit transmits a reset command to the drive control unit 22 and the communication control unit 34, respectively. The drive control unit 22 and the communication control unit 34 receive the reset command from the reset circuit and are then able to perform a reset operation.

[0090] The above-described configuration also makes it possible to prevent the communication control unit from unintentionally falling into an uncontrollable state. Furthermore, it is possible to reliably execute the reset operation. The configuration of this modification may be applied to a power tool in combination with the configurations of the other embodiments and modifications.

[0091] [Variation 3] The power tool according to this modification includes a second power switch provided on a power line connecting the communication battery 46BP and the second power control unit 42PC. The communication control unit 34 also includes a built-in power-on reset circuit (POR circuit).

[0092] When a reset operation is performed in this power tool, the second power switch is configured to cut off the power supply (an example of the "supply of the second power supply voltage") from the communication battery 46BP to the second power control unit 42PC. The POR circuit of the communication control unit 34 is configured to perform a reset operation when the power supply is cut off.

[0093] In the above embodiment and modified examples, the conditions and timing for the drive control unit 22, which is the first control unit, to perform the reset operation may be different from the conditions and timing for the communication control unit 34, which is the second control unit, to perform the reset operation.

[0094] For example, when the drive control unit 22 executes a reset operation, the communication control unit 34 may be configured not to execute a reset operation. On the other hand, when the communication control unit 34 executes a reset operation, the drive control unit 22 may be configured not to execute a reset operation.

[0095] For example, the drive control unit 22 may be configured to execute a reset operation using a built-in POR circuit when the battery 46BP is attached and power supply starts, while the communication control unit 34, which has already been supplied with power at this time, does not execute a reset operation. Also, when the handshake of the first embodiment is performed, the communication control unit 34 may be configured to execute a reset operation, while the drive control unit 22 does not execute a reset operation at this time.

[0096] The present invention can be modified in various ways. For example, the reset operation may be executed at a specific time. Alternatively, the reset operation may be executed when a specific time has elapsed since the reset operation was executed. Furthermore, the communication control unit 34 may be configured to execute the reset operation when the power supply source is switched from the battery 46B to the battery 10BP, or when the power supply source is switched from the battery 10BP to the battery 46B.

[0097] For example, the power supply may be configured to be cut off for a predetermined period of time when the power supply source is switched, and by incorporating a POR circuit in the communication control unit 34, a reset operation may be performed when the power supply source is switched.

[0098] The present invention can be modified in various ways without departing from the spirit of the invention. For example, within the scope of ordinary creativity of a person skilled in the art, some components in a certain embodiment can be replaced with other known elemental technologies. Also, some components in a certain embodiment can be replaced with other known elemental technologies. For example, the drive control unit and the communication control unit can operate at different voltages. [Explanation of symbols]

[0099] 10 Rebar binding machine (power tool) 10H handle 10HT Trigger 10M Magazine 10B Main body 10BP Battery (Battery Pack, 1st Battery) 12 Wire feed section 12G Gear 12M Feed Motor 14 Curl forming section 14A Curl Guide 14B Guidance guide 16 Cut section 16A Transmission Mechanism 18 Binding section 18H hook 18M Binding Motor (Electric Motor) 22 drive control unit (first control unit) 24 Motor control unit 26 Motor control unit 30 Communications Department 32 Communication Device 34 Communication control unit (second control unit) 36 Location information acquisition unit 40 Power supply 40CB cable 40CN battery connection 40D Diode (reverse current prevention circuit) 40S Power Switch 41 First voltage line 41A 1st wiring section 41B 2nd wiring section 41C 3rd wiring section 41PCB First wiring board 41PC First power control unit (first voltage supply unit) 41CN 1st connection part (1st connector) 42 Second voltage line 42PC Second power control unit (second voltage supply unit) 42CN Second connection part (second connector) 43 Third voltage line 42PCB Second wiring board 42BP Second Battery RL Reel W Wire RB rebar

Claims

1. An electric motor, A first battery; A second battery; a first control unit configured to be able to control the electric motor with a first operating voltage supplied based on a first power supply voltage supplied from the first battery; A communication device and a second control unit configured to be able to control the communication device with a second operating voltage supplied based on the first power supply voltage supplied from the first battery, and configured to be able to control the communication device with the second operating voltage supplied based on the second power supply voltage supplied from the second battery when the first power supply voltage is not supplied from the first battery; Equipped with the first control unit is configured to be able to transmit a signal to the second control unit, the second control unit is configured to be able to transmit a response signal to the first control unit in response to the signal, the first control unit is configured to be able to supply a reset signal to the second control unit to cause the second control unit to execute a reset operation when the response signal is not received, The second control unit executes the reset operation when the reset signal is supplied. Power tools.

2. An electric motor; A first battery; A second battery; a first control unit configured to be able to control the electric motor with a first operating voltage supplied based on a first power supply voltage supplied from the first battery; A communication device and a second control unit configured to be able to control the communication device with a second operating voltage supplied based on the first power supply voltage supplied from the first battery, and configured to be able to control the communication device with the second operating voltage supplied based on the second power supply voltage supplied from the second battery when the first power supply voltage is not supplied from the first battery; Equipped with the communication device is configured to, when receiving a reset command, supply a reset signal to the second control unit to cause the second control unit to execute a reset operation; The second control unit executes a reset operation of the second control unit when the reset signal is supplied. Power tools.

3. An electric motor; A first battery; A second battery; a first control unit configured to be able to control the electric motor with a first operating voltage supplied based on a first power supply voltage supplied from the first battery; A communication device and a second control unit configured to be able to control the communication device with a second operating voltage supplied based on the first power supply voltage supplied from the first battery, and configured to be able to control the communication device with the second operating voltage supplied based on the second power supply voltage supplied from the second battery when the first power supply voltage is not supplied from the first battery; a switch for cutting off the supply of the second power supply voltage from the second battery; Equipped with The second control unit is configured to be able to execute a reset operation of the second control unit when the supply of the second power supply voltage from the second battery is cut off by the switch.

4. A first voltage supply unit configured to be able to supply the first operating voltage for operating the first control unit based on the first power supply voltage supplied from the first battery; a second voltage supply unit configured to be able to supply the second operating voltage for operating the second control unit based on the first power supply voltage supplied from the first battery and to be able to supply the second operating voltage for operating the second control unit based on the second power supply voltage supplied from the second battery; a first voltage line that connects the first voltage supply unit and the second voltage supply unit and is configured to be able to supply the first power supply voltage; a second voltage line that connects the first voltage supply unit and the second voltage supply unit and is configured to be able to supply a second voltage that is lower than the first power supply voltage; a first wiring substrate on which the first control unit and the first voltage supply unit are mounted; a second wiring board on which the second control unit and the second voltage supply unit are mounted; a first connector provided on the first wiring board; a second connector provided on the second wiring board; a cable connecting the first connector and the second connector, the cable including a power supply line constituting at least a part of the first voltage line and a power supply line constituting at least a part of the second voltage line; The power tool according to claim 1 , further comprising:

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