JP7758936B2 - Electrical Equipment - Google Patents

Description

The present invention relates to electrical equipment such as power tools.

Some electrical devices, such as power tools, have additional functions (auxiliary functions) in addition to their main function. For example, the impact driver described in Patent Document 1 below has a main function of tightening screws using a rotary impact mechanism, and an additional function of illuminating the work area with a light.

Japanese Patent Application Laid-Open No. 2011-056664

In electrical equipment that has both a main function and an additional function, the power supply voltage may become unstable depending on the operating state of the main function, causing the additional function to malfunction. If the additional function malfunctions due to an unstable power supply voltage, it will affect the usability of the main function and reduce convenience. Furthermore, depending on the configuration of the additional function, the wiring may become complicated and difficult to assemble.

The present inventors have recognized the following problems.
Problem 1: To provide an electrical device that can operate additional functions normally even if the power supply voltage becomes unstable.
Problem 2: To provide an electrical device that can operate its main functions normally even if the power supply voltage becomes unstable.
Problem 3: To provide an electrical device that can suppress deterioration of assembly and manufacturing costs due to the addition of additional functions.
Problem 4: To provide an electrical device that can operate normally even when it has an additional function that requires a voltage higher than the power supply voltage.

The present invention aims to solve at least one of the above problems 1 to 4.

One aspect of the present invention is an electric device.
a first load unit driven by power from a power supply unit;
a voltage conversion unit connected between the power supply unit and the first load unit, which converts an output voltage of the power supply unit and supplies the converted output voltage to the first load unit;
a control unit that controls the first load unit;
a second load unit driven by power from the power supply unit;
a drive unit connected between the power supply unit and the second load unit and configured to drive the second load unit;
Equipped with
the voltage conversion unit includes a first conversion unit connected to the power supply unit and a second conversion unit connected to the first conversion unit and the first load unit ,
The output of the second conversion unit serves as a power source for the drive unit.
It is characterized by :
Another aspect of the present invention is an electric device.
a first load unit driven by power from a power supply unit;
a voltage conversion unit connected between the power supply unit and the first load unit, which converts an output voltage of the power supply unit and supplies the converted output voltage to the first load unit;
a control unit that controls the first load unit;
Equipped with
the voltage conversion unit includes a first conversion unit connected to the power supply unit and a second conversion unit connected to the first conversion unit and the first load unit,
the first load section includes a plurality of LEDs connected in series with each other;
The second conversion unit outputs a voltage higher than an operating voltage of the plurality of LEDs.
It is characterized by:
Another aspect of the present invention is an electric device.
a first load unit driven by power from a power supply unit;
a voltage conversion unit connected between the power supply unit and the first load unit, which converts an output voltage of the power supply unit and supplies the converted output voltage to the first load unit;
a control unit that controls the first load unit;
a housing that accommodates the voltage conversion unit and the control unit;
Equipped with
the voltage conversion unit includes a first conversion unit connected to the power supply unit and a second conversion unit connected to the first conversion unit and the first load unit,
the power supply unit is a battery pack that is detachable from the housing,
the second conversion unit boosts the output voltage of the first conversion unit to a voltage higher than a discharge-inhibition voltage of the battery pack;
It is characterized by:

The present invention may also be expressed as a "work machine" or "power tool," and such expressions are also valid aspects of the present invention.

The present invention can solve at least one of the above problems 1 to 4.

1 is a side view of an electrical device 1 according to an embodiment of the present invention. FIG. 1A is a front view of the electric device 1. FIG. 1B is a front view of an LED board 35 of the electric device 1. FIG. 2 is a circuit block diagram of the electrical device 1. 4 is a simplified graph showing an example of changes over time in the current flowing through the motor 3, the output voltage of the battery pack 7, and the illuminance of the light-emitting diodes D1 to D3 in the electrical appliance 1. 10 is a simplified graph showing another example of changes over time in the current flowing through the motor 3, the output voltage of the battery pack 7, and the illuminance of the light-emitting diodes D1 to D3 in the electrical device 1. A simplified graph showing an example of the change over time in the current flowing through the motor 3, the output voltage of the battery pack 7, and the illuminance of the light-emitting diodes D1 to D3 in an electrical device of a comparative example, which is configured so that the voltage of the battery pack 7 is directly applied to the light-emitting diodes D1 to D3. 10 is a simplified graph showing another example of changes over time in the current flowing through the motor 3, the output voltage of the battery pack 7, and the illuminance of the light-emitting diodes D1 to D3 in the electrical device of the comparative example.

In the following, identical or equivalent components, parts, etc. shown in each drawing will be given the same reference numerals, and duplicate explanations will be omitted where appropriate. The embodiments are illustrative and do not limit the invention. Not all features or combinations thereof described in the embodiments are necessarily essential to the invention.

This embodiment relates to an electrical device 1. Figures 1 and 2 define the mutually orthogonal front-to-rear and up-to-down directions of the electrical device 1. The front-to-rear direction is a direction parallel to the motor shaft 3a of the electrical device 1. The electrical device 1 is an electric power tool, specifically an impact driver.

The electrical device 1 has a housing 2. The housing 2 includes a body portion 2a, a handle portion 2b, and a battery attachment/detachment portion 2c.

The body 2a is a cylindrical part whose central axis is approximately parallel to the front-to-rear direction. The housing 2 includes a hammer case 11, made of, for example, metal, connected to the front of the body 2a. The front surface of the hammer case 11 is covered by a front cap 12, which is a protective member.

The upper end of the handle portion 2b is connected to the front-to-rear intermediate portion of the body portion 2a and extends downward from said intermediate portion. The electrical device 1 has a trigger switch 6 and a forward/reverse switching lever 13 (forward/reverse switching button) at the upper end of the handle portion 2b. The trigger switch 6 is an operating part that allows the user to switch between driving and stopping the motor 3 (the driving state of the motor 3). The trigger switch 6 is an infinitely variable speed switch. The forward/reverse switching lever 13 is a rotation direction switching part that allows the user to switch between forward and reverse rotation of the motor 3, i.e., forward and reverse rotation of the anvil 10 (described below).

The battery attachment/detachment section 2c is located at the bottom end of the handle section 2b, and allows the battery pack 7, which serves as the power source, to be detachably attached. The electrical device 1 operates on power from the battery pack 7. Here, as an example, the rated voltage of the battery pack 7 is assumed to be 10.8V (3.6V cells x 3).

The electrical device 1 has an operation panel 20 (switch panel) on the front upper surface of the battery attachment/detachment section 2c. The user can use the operation panel 20 to turn on/off the lighting switch 39 shown in Figure 4. The electrical device 1 has a control board 30 inside the battery attachment/detachment section 2c.

The electrical device 1 includes a motor 3 as a second load section, a reduction mechanism 4, a spindle 5, a hammer 8, a spring 9, and an anvil 10 as a tool attachment section within the body section 2a and hammer case 11. The reduction mechanism 4, spindle 5, hammer 8, and spring 9 constitute a rotary impact mechanism that converts the driving force (rotational force) of the motor 3 into a rotary impact force that acts on the anvil 10.

The motor 3 is an inner rotor type brushless motor. The reduction mechanism 4 reduces the rotation of the motor 3 and transmits it to the spindle 5. The spindle 5 rotates the hammer 8. The spring 9 biases the hammer 8 forward. The hammer 8 rotates or rotary strikes the anvil 10. In other words, the anvil 10 is driven by the driving force of the motor 3. The anvil 10 is rotatably supported by the hammer case 11. Driving the anvil 10 by driving the motor 3 is the main function of the electrical device 1.

The electrical device 1 has a sensor/inverter board 15 inside the body 2a. The sensor/inverter board 15 is supported in front of the main body of the motor 3 (the part of the motor 3 excluding the motor shaft 3a) in a position approximately perpendicular to the motor shaft 3a. The sensor/inverter board 15 is equipped with a Hall IC 43 and an inverter circuit unit 45 shown in Figure 4.

The electrical device 1 has an LED board 35 as a lighting board around the front of the hammer case 11. The LED board 35 is supported inside the body 2a and front cap 12 in a position approximately perpendicular to the motor shaft 3a. The LED board 35 is annular with a notched top as shown in Figure 3(B), and surrounds the front of the hammer case 11 approximately coaxially.

The electrical device 1 has light-emitting diodes (LEDs) D1 to D3 as a first load, a pair of electrode portions 36 (terminal portions), and three conductor patterns 37 on the front surface of the LED board 35.

When viewed from the front, light-emitting diode D1 is located directly below the central axis of the anvil 10 (hereinafter referred to as the "central axis"). Light-emitting diodes D1 to D3 are arranged at 120-degree intervals (equidistant intervals) around the central axis. The front of light-emitting diodes D1 to D3 is covered by a lighting cover 34. Light-emitting diodes D1 to D3 are lighting units that illuminate the work area. The function of illuminating the work area using light-emitting diodes D1 to D3 is an additional function of electrical device 1.

The pair of electrode sections 36 are electrically connected to the control board 20 via wiring 38 shown in FIG. 2 and are electrically connected to a pair of output terminals of the boost circuit 32 shown in FIG. 4. The conductor pattern 37 connects the light-emitting diodes D1 to D3 in series between the pair of electrode sections 36.

Figure 4 is a circuit block diagram of electrical device 1. Capacitor C1 is used to prevent noise and is connected between the output terminals of battery pack 7. Resistor R is used for current or load detection and is connected to the path of the current flowing through motor 3 (hereinafter referred to as "motor current").

The electrical device 1 has a Hall IC 43 and an inverter circuit section 45 on the sensor/inverter board 15. The Hall IC 43 is a position sensor (magnetic sensor) for detecting the rotational position of the motor 3.

The inverter circuit unit 45 is connected between the battery pack 7 and the motor 3 and drives the motor 3. The inverter circuit unit 45 converts the DC power output by the battery pack 7 into drive power for the motor 3 and supplies it to the motor 3. The inverter circuit unit 45 includes, for example, six switching elements connected in a three-phase bridge. The motor 3 is driven by power from the battery pack 7.

The electrical device 1 has a control board 30 that includes a step-down circuit 31 as a first conversion unit, a step-up circuit 32 as a second conversion unit, a gate driver 40 (control signal output circuit) as a drive circuit unit, a lighting switch 39, a lighting drive circuit 41, and a calculation unit 42.

The step-down circuit 31 and the step-up circuit 32 are connected between the battery pack 7 and the light-emitting diodes D1-D3, and also between the battery pack 7 and the gate driver 40. The step-down circuit 31 and the step-up circuit 32 constitute a voltage conversion unit that converts the output voltage of the battery pack 7 (hereinafter referred to as "battery voltage") and supplies it to the light-emitting diodes D1-D3 and the gate driver 40.

The step-down circuit 31 is connected to the battery pack 7 via a diode D4 for preventing backflow and a capacitor C2 for preventing noise. The battery voltage is input to the step-down circuit 31 via diode D4 and capacitor C2. The step-down circuit 31 is, for example, a 5V regulator, and steps down the battery voltage to, for example, 5V before outputting it. The step-down circuit 31 is connected to the power input terminal of the calculation unit 42. The output voltage of the step-down circuit 31 becomes the power supply voltage for the calculation unit 42.

The boost circuit 32 is connected to the step-down circuit 31 and boosts the output voltage of the step-down circuit 31 to, for example, 12 V. The boost circuit 32 may be a general step-up DC-DC converter, such as a step-up switching regulator. The boost circuit 32 includes a boost IC 33, a choke coil L, a diode D5, and a capacitor C3. The boost IC 33 is a unit that incorporates a switching element connected in parallel with the capacitor C3 and its control circuit.

While the output voltage of the boost circuit 32 is constant, the battery voltage varies depending on the output current (hereinafter "battery current") and remaining capacity (hereinafter "remaining battery power") of the battery pack 7. The battery voltage is at its maximum (e.g., 12 V) when the battery is fully charged and the battery current is zero, and decreases as the remaining battery power decreases and as the output current increases. For this reason, the battery voltage can be lower than the output voltage of the boost circuit 32, or can become lower.

The output voltage of the boost circuit 32 is higher than the discharge prohibition voltage (hereinafter referred to as the "discharge prohibition voltage") of the battery pack 7. The discharge prohibition voltage is a voltage set to prevent over-discharge, and is, for example, 7.5 V (2.5 V/cell) when the motor 3 is stopped.

The boost circuit 32 is connected to the light-emitting diodes D1 to D3 and supplies a boosted output voltage to the light-emitting diodes D1 to D3. The boosted output voltage is higher than the total operating voltage of the series-connected light-emitting diodes D1 to D3, i.e., the minimum voltage required to light the light-emitting diodes D1 to D3 (hereinafter referred to as the "LED on voltage"). The LED on voltage is higher than the discharge-inhibition voltage.

The boost circuit 32 is connected to the gate driver 40 and supplies the boosted output voltage to the gate driver 40 as a power supply voltage. The gate driver 40 is an example of a first load unit. That is, in the electrical device 1, the light-emitting diodes D1 to D3 and the gate driver 40 each constitute a first load unit.

Under the control of the calculation unit 42, the gate driver 40 transmits (applies) a drive signal, such as a PWM (Pulse Width Modulation) signal, to the control terminal (each gate) of each switching element in the inverter circuit unit 45. The gate driver 40 includes a bootstrap circuit for driving the high-side switching elements of the inverter circuit unit 45. Together with the inverter circuit unit 45, the gate driver 40 constitutes a drive unit that drives the motor 3. The output voltage of the boost circuit 32 serves as the power source for the drive unit.

The lighting switch 39 is a switch that can be turned on and off by the user, and sends a lighting switching signal in response to the user's operation to the calculation unit 42. The lighting drive circuit 41 controls the lighting state of the light-emitting diodes D1 to D3 according to the control of the calculation unit 42.

The calculation unit 42 includes an MCU (Micro Controller Unit). The calculation unit 42 constitutes a control unit that controls the overall operation of the electrical device 1. The calculation unit 42 controls the illumination of the light-emitting diodes D1 to D3 through control of the lighting drive circuit 41. The calculation unit 42 controls the drive of the motor 3 through control of the gate driver 40.

The calculation unit 42 detects the current flowing through the motor 3 (hereinafter referred to as "motor current") from the voltage across both terminals of the resistor R. The calculation unit 42 detects the load on the motor 3 from the motor current. The calculation unit 42 detects the on/off status and operation amount (pulling amount) of the trigger switch 6. The calculation unit 42 detects the rotation direction indicated by the forward/reverse switching lever 13 (hereinafter referred to as "rotation indication direction"). The calculation unit 42 detects the rotation position of the motor 3 (hereinafter referred to as "motor rotation position") and the rotation speed of the motor 3 (hereinafter referred to as "motor rotation speed") from the output signal of the Hall IC 43.

The calculation unit 42 controls the gate driver 40 and controls the driving of the motor 3 according to the motor current, the on/off and operation amount of the trigger switch 6, the rotation direction, the motor rotation position, and the motor rotation speed.

Figure 5 is a simplified graph showing an example of changes over time in motor current, battery voltage, and illuminance of light-emitting diodes D1 to D3 (hereinafter "LED illuminance") in electrical device 1. In this graph, it is assumed that the lighting switch 39 is always on. The same applies to Figures 6 to 8 described below.

At time t1, the user turns on the trigger switch 6, starting the motor 3 and causing the motor current to rise. As the motor current rises, the battery voltage drops, and at time t2 the battery voltage falls below the LED-on voltage. Thereafter, the motor current changes depending on the task, and the battery voltage repeatedly rises above and falls below the LED-on voltage.

Specifically, the battery voltage exceeds the LED-on voltage at time t3, falls below the LED-on voltage at time t4, exceeds the LED-on voltage at time t5, falls below the LED-on voltage at time t6, and exceeds the LED-on voltage at time t7.

The motor current then decreases further, reaching zero at time t8. This causes the battery voltage to recover, but because the remaining battery charge is lower than it was before time t1, the battery voltage remains slightly lower than it was before time t1. Note that the moment the motor current begins to decrease between times t6 and t7 is when the user turns off the trigger switch 6.

During this series of operations, the battery voltage fluctuates above and below the LED on voltage, but because a constant drive voltage is supplied to light-emitting diodes D1 to D3 from boost circuit 32, the LED illuminance remains constant throughout.

Figure 6 is a simplified graph showing another example of changes in motor current, battery voltage, and LED illuminance over time for electrical device 1.

At time t11, the user turns on the trigger switch 6, starting the motor 3 and causing the motor current to rise. The motor current continues to rise until time t13, remains constant from time t13 to t14, and then drops to zero from time t14 to t16.

Battery voltage changes as the motor current changes. Specifically, battery voltage begins to decrease from time t11, falls below the LED on voltage at time t12, continues to decrease until time t13, remains constant from time t13 to t14, and then increases from time t14 to t16. As in the case of Figure 5, because the remaining battery power is lower than before time t11, the battery voltage at time t16 remains slightly lower than before time t11. Note that time t14 is when the user turns off the trigger switch 6.

During this series of operations, the battery voltage remains below the LED on voltage between times t12 and t15, but because a constant drive voltage is supplied to light-emitting diodes D1 to D3 from boost circuit 32, the LED illuminance remains constant throughout, including between times t12 and t15.

Figure 7 is a simplified graph showing an example of the changes over time in motor current, battery voltage, and LED illuminance in a comparative electrical device in which the voltage of the battery pack 7 is applied directly to light-emitting diodes D1 to D3. The changes over time in motor current and battery voltage in Figure 7 are the same as those in Figure 5.

In the electrical device of the comparative example, as the battery voltage decreases between times t1 and t2, the LED illuminance decreases. When the battery voltage falls below the LED on voltage at time t2, light-emitting diodes D1 to D3 turn off (LED illuminance becomes zero). During the period from times t2 to t7, the battery voltage temporarily exceeds the LED on voltage between times t3 and t4 and between times t5 and t6, and light-emitting diodes D1 to D3 turn on (LED illuminance rises slightly). As the battery voltage increases between times t7 and t8, the LED illuminance increases.

Figure 8 is a simplified graph showing another example of the changes over time in motor current, battery voltage, and LED illuminance for the electrical device of the comparative example. The changes over time in motor current and battery voltage in Figure 8 are the same as the changes over time in motor current and battery voltage in Figure 6.

In the electrical device of the comparative example, as the battery voltage decreases between times t11 and t12, the LED illuminance decreases. When the battery voltage falls below the LED on voltage at time t12, light-emitting diodes D1 to D3 turn off (LED illuminance becomes zero). Light-emitting diodes D1 to D3 remain off until time t15. As the battery voltage increases between times t15 and t16, the LED illuminance increases.

As described above, in the electrical device of the comparative example, fluctuations in battery voltage cause fluctuations in LED illuminance, resulting in flickering. Furthermore, when the battery voltage falls below the LED on voltage, light-emitting diodes D1 to D3 turn off. Flickering or unintentional turning-off of light-emitting diodes D1 to D3 reduces workability. This embodiment effectively solves these issues of the comparative example.

This embodiment can achieve the following effects:

(1) The light-emitting diodes D1 to D3 are driven by the stable output voltage of the boost circuit 32, which is not affected by fluctuations in battery voltage. This ensures constant LED illumination even when battery voltage fluctuates due to motor current or remaining battery charge, resulting in improved workability and convenience.

(2) The boost circuit 32 can output a voltage higher than the battery voltage. This allows the light-emitting diodes D1 to D3 to operate (light up) normally even when a voltage higher than the battery voltage is required to operate (light up) the light-emitting diodes D1 to D3, providing excellent convenience.

(3) The boost circuit 32 receives the stable output voltage of the step-down circuit 31, which is unaffected by fluctuations in battery voltage, as its input. This enables stable boost operation even when battery voltage fluctuates due to motor current or remaining battery charge. Furthermore, an inexpensive integrated circuit (IC) with a narrow input voltage range can be used as the boost circuit 32, helping to keep costs down.

(4) Because the output voltage of the step-down circuit 31, which serves as the power source for the calculation unit 42, is used as the input voltage for the step-up circuit 32, there is no need to prepare a separate power supply circuit to generate the input voltage for the step-up circuit 32, reducing the number of parts and costs.

(5) Because the light-emitting diodes D1 to D3 are connected in series, the wiring 38 connecting the LED board 35 and the control board 30 can be made less complicated than when they are connected in parallel. This also prevents the conductor pattern 37 on the LED board 35 from becoming more complex, thereby reducing assembly difficulties and manufacturing costs.

(6) Because the boost circuit 32 supplies the gate driver 40 with a stable output voltage that is not affected by fluctuations in battery voltage, the gate driver 40 can be driven stably even if the battery voltage fluctuates due to motor current or remaining battery charge, and the drive signal for the switching elements of the inverter circuit unit 45 can be stabilized.

(7) A single boost circuit 32 can ensure both the drive voltage for the light-emitting diodes D1 to D3 and the supply voltage to the gate driver 40, thereby reducing the number of components and costs.

The present invention has been described above using exemplary embodiments, but those skilled in the art will understand that various modifications are possible to the components and processes of the embodiments within the scope of the claims. Modifications are discussed below.

The rated voltage of the battery pack 7, the output voltage of the step-down circuit 31, the output voltage of the step-up circuit 32, the number of light-emitting diodes (number connected in series) serving as the first load, and other specific values given as examples in the embodiments do not limit the scope of the invention in any way and can be changed as desired to suit the required specifications.

For example, the rated voltage of the battery pack 7 may be 14.4V (four 3.6V cells) or 18V (five 3.6V cells). The output voltage of the boost circuit 32 may exceed 12V as long as it is within the range that the gate driver 40 can accept as an input voltage. If the gate driver 40 is a bootstrap circuit, the output voltage of the boost circuit 32 is preferably 20V or less.

The electrical device of the present invention may be a power tool other than an impact driver, or may be an electrical device other than a power tool. The power supply is not limited to a detachable battery pack, but may be a battery built into the electrical device itself, or may be a commercial power source.

1...electrical equipment, 2...housing, 2a...body portion, 2b...handle portion, 2c...battery attachment/detachment portion, 3...motor, 3a...motor shaft, 4...reduction mechanism, 5...spindle, 6...trigger switch (operation portion), 7...battery pack, 8...hammer, 9...spring, 10...anvil (tip tool attachment portion), 11...hammer case, 12...front cap (protective member), 13...forward/reverse switch lever (rotation direction switch portion), 15...sensor/inverter board, 20...operation panel (switch panel), 30...control board, 31...step-down Circuit (first conversion unit), 32...Boost circuit (second conversion unit), 33...Boost IC, 34...Lighting cover, 35...LED board (lighting board), 36...Electrode unit (terminal unit), 37...Conductor pattern, 38...Wiring, 39...Lighting switch, 40...Gate driver (control signal output circuit), 41...Lighting drive circuit, 42...Calculation unit (control unit), 43...Hall IC (magnetic sensor), 45...Inverter circuit unit, C1-C3...Capacitors, D1-D3...Light-emitting diodes (light-emitting elements), D4, D5...Diodes, L...Choke coil.

Claims (11)

a first load unit driven by power from a power supply unit;
a voltage conversion unit connected between the power supply unit and the first load unit, which converts an output voltage of the power supply unit and supplies the converted output voltage to the first load unit;
a control unit that controls the first load unit;
a second load unit driven by power from the power supply unit;
a drive unit connected between the power supply unit and the second load unit and configured to drive the second load unit;
Equipped with
the voltage conversion unit includes a first conversion unit connected to the power supply unit and a second conversion unit connected to the first conversion unit and the first load unit ,
The output of the second conversion unit serves as a power source for the drive unit.
An electrical device characterized by: a first load unit driven by power from a power supply unit;
a voltage conversion unit connected between the power supply unit and the first load unit, which converts an output voltage of the power supply unit and supplies the converted output voltage to the first load unit;
a control unit that controls the first load unit;
Equipped with
the voltage conversion unit includes a first conversion unit connected to the power supply unit and a second conversion unit connected to the first conversion unit and the first load unit,
the first load section includes a plurality of LEDs connected in series with each other;
The second conversion unit outputs a voltage higher than an operating voltage of the plurality of LEDs.
An electrical device characterized by: 3. The electrical device according to claim 1,
The first conversion unit steps down the output voltage of the power supply unit and outputs the resulting voltage.
An electrical device characterized by: 4. The electrical device according to claim 1,
The second conversion unit boosts the output voltage of the first conversion unit and outputs the boosted output voltage.
Electrical equipment characterized by 5. The electrical device according to claim 4 ,
The output voltage of the power supply unit is lower than or may be lower than the output voltage of the second conversion unit.
An electrical device characterized by: 2. The electrical device according to claim 1 ,
the drive unit includes an inverter circuit unit connected to the second load unit and a drive circuit unit that transmits a drive signal to the inverter circuit unit,
the first load unit has the drive circuit unit;
An electrical device characterized by: 7. The electrical device according to claim 1,
The output of the first conversion unit serves as a power source for the control unit.
An electrical device characterized by: 8. An electrical device according to any one of claims 1 to 7 ,
a housing that accommodates the voltage conversion unit and the control unit,
The power supply unit is a battery pack that is detachable from the housing.
An electrical device characterized by: 9. The electrical device according to claim 8 ,
the second conversion unit boosts the output voltage of the first conversion unit to a voltage higher than a discharge-inhibition voltage of the battery pack;
An electrical device characterized by: 3. The electrical device according to claim 2 ,
a housing that accommodates the voltage conversion unit and the control unit,
the power supply unit is a battery pack that is detachable from the housing,
an operating voltage of the plurality of LEDs is higher than a discharge prohibition voltage of the battery pack;
An electrical device characterized by: a first load unit driven by power from a power supply unit;
a voltage conversion unit connected between the power supply unit and the first load unit, which converts an output voltage of the power supply unit and supplies the converted output voltage to the first load unit;
a control unit that controls the first load unit;
a housing that accommodates the voltage conversion unit and the control unit;
Equipped with
the voltage conversion unit includes a first conversion unit connected to the power supply unit and a second conversion unit connected to the first conversion unit and the first load unit,
the power supply unit is a battery pack that is detachable from the housing,
the second conversion unit boosts the output voltage of the first conversion unit to a voltage higher than a discharge-inhibition voltage of the battery pack;
An electrical device characterized by: