Power tool

Abstract

To facilitate visual recognition of a work being worked on.SOLUTION: A power tool includes: a motor having a stator and a rotor rotatable with respect to the stator; an output shaft disposed further forward than the motor and rotated by the motor; a motor housing portion for housing the motor; a grip portion disposed below the motor housing portion; a battery holding portion disposed below the grip portion; and a COB light disposed in the battery holding portion.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The technology disclosed in this specification relates to power tools. [Background technology]

[0002] The power tool includes an output shaft to which a tool tip is attached and a light unit that illuminates a work target. Patent Document 1 discloses a power tool having an illumination unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-024044 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, if a part of the light emitted from the light unit is irradiated onto the tool tip, a shadow may be cast on the work object. If a shadow is cast on the work object, the worker may have difficulty visually recognizing the work object. In addition, if the luminance of the light emitted from the light unit is low, the worker may have difficulty visually recognizing the work object.

[0005] The technology disclosed in this specification aims to make it easier to visually recognize the work target. [Means for solving the problem]

[0006] This specification discloses an electric power tool, which may include a motor having a stator and a rotor rotatable relative to the stator, an output shaft disposed forward of the motor and rotated by the motor, a motor housing that houses the motor, a grip disposed below the motor housing, a battery holder disposed below the grip, and a COB light disposed in the battery holder. Effect of the Invention

[0007] According to the technology disclosed in this specification, the work target can be easily visually recognized. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a front perspective view showing a driver drill according to an embodiment. [Diagram 2] FIG. 2 is a side view showing the driver drill according to the embodiment. [Diagram 3] FIG. 3 is a cross-sectional view showing a driver drill according to an embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing an upper portion of the driver drill according to the embodiment. [Diagram 5] FIG. 5 is a cross-sectional view showing the light unit according to the embodiment. [Figure 6] FIG. 6 is a perspective view showing a light unit according to the embodiment. [Figure 7] FIG. 7 is a block diagram showing a driver drill according to the embodiment. [Figure 8] FIG. 8 is a block diagram showing the driver drill according to the embodiment. [Figure 9] FIG. 9 is a diagram showing an LED element mounted on a substrate according to an embodiment. [Figure 10] FIG. 10 is a diagram showing the entire circuit configuration of an LED circuit in the case of four LED elements according to the embodiment. [Figure 11] FIG. 11 is a diagram showing a circuit configuration of an LED circuit according to an embodiment in which there are four LED elements. [Figure 12] FIG. 12 is a diagram showing a circuit configuration of an LED circuit according to an embodiment in which there are four LED elements. [Figure 13] FIG. 13 is a diagram showing an LED element mounted on a substrate according to an embodiment. [Figure 14] FIG. 14 is a diagram showing the entire circuit configuration of an LED circuit in the case of six LED elements according to the embodiment. [Figure 15]FIG. 15 is a diagram showing a circuit configuration of an LED circuit in which there are six LED elements according to the embodiment. [Figure 16] FIG. 16 is a diagram showing a circuit configuration of an LED circuit in which there are six LED elements according to the embodiment. [Figure 17] FIG. 17 is a perspective view showing an optical member according to an embodiment. [Figure 18] FIG. 18 is an enlarged view of a part of the optical member according to the embodiment. [Figure 19] FIG. 19 is a front perspective view showing the polisher according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In one or more embodiments, the power tool may include a motor having a stator and a rotor rotatable relative to the stator, an output shaft positioned forward of the motor and rotated by the motor, a motor housing portion that houses the motor, a grip portion positioned below the motor housing portion, a battery holding portion positioned below the grip portion, and a COB light positioned in the battery holding portion.

[0010] In the above configuration, high-intensity light is emitted from the COB light located below the grip. This brightly illuminates the work target. In addition, the shadow of the tool tip is less likely to be cast on the work target. This makes it easier for the worker to see the work target.

[0011] In one or more embodiments, the COB light may be located at the front of the battery holder.

[0012] With the above configuration, the work target in front of the battery holding portion is brightly illuminated.

[0013] In one or more embodiments, the COB light may include a substrate and an LED device mounted on a front surface of the substrate. The substrate may be elongated in the left-right direction.

[0014] The above configuration allows illumination of a wide range of the work subject.

[0015] In one or more embodiments, a plurality of LED elements may be mounted with spaces between them in the left-right direction.

[0016] In the above configuration, even if some of the light emitted from the LED element is irradiated onto the tool tip, the LED elements are mounted at intervals in the left-right direction, so the shadows of the tool tip are cancelled out. As a result, the shadows cast on the work object are not noticeable. Therefore, the worker can easily see the work object.

[0017] In one or more embodiments, the power tool may include an optical member disposed forward of the COB light and having a light-transmitting portion through which light emitted from the COB light passes.

[0018] In the above configuration, the light transmitted through the optical member is irradiated onto the work object.

[0019] In one or more embodiments, the optical element may be disposed in a light opening in the battery holder.

[0020] In the above configuration, the light transmitted through the optical member is irradiated onto the work object without any loss.

[0021] In one or more embodiments, the optical element may be made of polycarbonate resin that has a white diffusing agent added thereto.

[0022] In the above configuration, since the optical member is milky white, it is difficult to see the outer shape of the element, such as the LED element of the COB light, from the outside of the power tool. Since the outer shape of the element is difficult to see, the design of the power tool is improved.

[0023] In one or more embodiments, the optical element may have a light transmittance of 40% or more and 70% or less.

[0024] In the above configuration, the outer shape of the COB light element is difficult to see from the outside of the power tool. Because the outer shape of the element is difficult to see, the design of the power tool is improved.

[0025] In one or more embodiments, the optical element may have an incident surface onto which light from the COB light is incident, a total reflection surface that totally reflects the light from the COB light, and an exit surface that exits the light from the incident surface and the light from the total reflection surface.

[0026] In the above configuration, even if a portion of the light emitted from the COB light is not incident on the entrance surface of the light-transmitting portion, it is reflected by the total reflection surface and emitted from the exit surface, thereby reducing the loss of light emitted from the COB light.

[0027] In one or more embodiments, the total internal reflection surface may be located above the input surface.

[0028] In the above configuration, even if a portion of the light emitted from the COB light travels above the light transmitting portion, it is reflected by the total reflection surface and emitted from the emission surface, thereby reducing loss of the light emitted from the COB light.

[0029] In one or more embodiments, the optical element may have an upper enclosure portion extending rearward from an upper end of the light-transmitting portion and an upper convex portion protruding upward from the upper enclosure portion. The total reflection surface may be disposed on the upper convex portion.

[0030] In the above configuration, the upper convex portion having the total reflection surface can function as a positioning portion for the optical member relative to the battery holding portion.

[0031] In one or more embodiments, the optical member may have a lower surrounding portion extending rearward from a lower end of the light-transmitting portion, and a lower convex portion protruding downwardly from the lower surrounding portion.

[0032] In the above configuration, the lower convex portion can function as a positioning portion for the optical member relative to the battery holding portion, and the upper convex portion and the lower convex portion can function as rotation stoppers for the optical member relative to the battery holding portion.

[0033] In one or more embodiments, the COB light may include a substrate and an LED device mounted on a front surface of the substrate. An angle between a rotation axis of the motor and a normal to the front surface of the substrate may be between 5 degrees and 20 degrees.

[0034] With the above-described configuration, the work target can be properly illuminated with the tool bit at the center.

[0035] In one or more embodiments, the COB light may include a substrate and an LED element mounted on a front surface of the substrate. At least four LED elements may be mounted at intervals in the left-right direction. A first group of LED elements including a first LED element and a second LED element may be connected in series, a second group of LED elements including a third LED element and a fourth LED element may be connected in series, and the first group of LED elements and the second group of LED elements may be connected in parallel. The second group of LED elements may be disposed between the first LED element and the second LED element in the left-right direction.

[0036] In the above configuration, even if an imbalance in the current supplied to the COB light causes an imbalance in the luminous intensity of the light emitted from the first group of LED elements and the luminous intensity of the light emitted from the second group of LED elements, the difference in illuminance between the left and right sides of the work object can be reduced.

[0037] In one or more embodiments, a third group of LED elements including a fifth LED element and a sixth LED element are connected in series, the first group of LED elements, the second group of LED elements and the third group of LED elements are connected in parallel, and in the left-right direction, the second group of LED elements are arranged between the first LED elements and the second LED elements, and the third group of LED elements are arranged between the third LED elements and the fourth LED elements.

[0038] In the above configuration, even if an imbalance in the current supplied to the COB light causes an imbalance in the luminous intensity of the light emitted from the first group of LED elements and the luminous intensity of the light emitted from the second group of LED elements, the illuminance on the work object can be made uniform.

[0039] In one or more embodiments, the power tool may include a motor having a stator and a rotor rotatable relative to the stator, an output shaft rotated by the rotor, a housing that accommodates the motor, and a COB light disposed in the housing. The rated voltage of the battery held in the battery holding portion of the housing may be 25.2 V or more.

[0040] In the above configuration, the COB light can be driven with a high voltage, so the work target is brightly illuminated, making it easier for the worker to see the work target.

[0041] In one or more embodiments, a power tool may include a motor having a stator and a rotor rotatable relative to the stator, an output shaft rotated by the rotor, a housing that accommodates the motor, and a COB light disposed in the housing. The rated voltage of the battery held in the battery holding portion of the housing may be 21.6 V or more, and the voltage of the battery may be applied to the COB light without being stepped down.

[0042] In the above configuration, the COB light can be driven with a high voltage, so the work target is brightly illuminated, making it easier for the worker to see the work target.

[0043] In one or more embodiments, the COB light may include a substrate and an LED element mounted on the substrate. At least six LED elements may be mounted. The at least six LED elements may be connected in series.

[0044] In the above configuration, the work target is brightly illuminated by at least six LED elements connected in series, making it easier for the worker to see the work target.

[0045] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited thereto. The components of the embodiments described below can be appropriately combined. In addition, some components may not be used.

[0046] In the embodiments, the positional relationship of each part will be described using the terms left, right, front, rear, top, and bottom. These terms indicate a relative position or direction based on the center of the power tool.

[0047] The electric power tool has a motor. In the embodiments, a direction parallel to a rotation axis AX of the motor is referred to as an axial direction, a direction going around the rotation axis AX is referred to as a circumferential direction or a rotation direction, and a radial direction of the rotation axis AX is referred to as a radial direction.

[0048] In the embodiment, the rotation axis AX extends in the front-rear direction. The axial direction and the front-rear direction coincide with each other. One axial side is the front, and the other axial side is the rear. In addition, in the radial direction, a position closer to or a direction approaching the rotation axis AX is appropriately referred to as the radial inner side, and a position farther from or a direction away from the rotation axis AX is appropriately referred to as the radial outer side.

[0049] In the embodiment, the power tool is a driver drill, which is a type of screw tightening tool. The power tool will be referred to as a driver drill as appropriate.

[0050] [Driver Drill Overview] Fig. 1 is a front perspective view showing the driver drill 1 according to the embodiment. Fig. 2 is a side view showing the driver drill 1 according to the embodiment. Fig. 3 is a cross-sectional view showing the driver drill 1 according to the embodiment. In the embodiment, the driver drill 1 is a vibration driver drill.

[0051] As shown in Figures 1, 2, and 3, the driver drill 1 includes a housing 2, a rear cover 3, a casing 4, a battery mounting section 5, a motor 6, a power transmission mechanism 7, an output section 8, a fan 9, a trigger lever 10, a forward / reverse rotation switch lever 11, a speed switch lever 12, a mode switch ring 13, a light unit 14, an interface panel 15, a dial 16, and a controller 18.

[0052] The housing 2 is made of synthetic resin. In this embodiment, the housing 2 is made of nylon. The housing 2 includes a left housing 2L and a right housing 2R. The left housing 2L and the right housing 2R are fixed together by a screw 2S. The housing 2 is formed by fixing the left housing 2L and the right housing 2R together.

[0053] The housing 2 has a motor accommodating portion 21, a grip portion 22, a battery holding portion 23, and a light holding portion 24.

[0054] The motor accommodating portion 21 accommodates the motor 6. The motor accommodating portion 21 is cylindrical.

[0055] The grip portion 22 is held by an operator. The grip portion 22 is disposed below the motor accommodating portion 21. The grip portion 22 extends downward from the motor accommodating portion 21. The trigger lever 10 is disposed in front of the grip portion 22.

[0056] The battery holding section 23 houses the controller 18. The battery holding section 23 holds the battery 20 via the battery attachment section 5. The battery holding section 23 is disposed below the grip section 22. The battery holding section 23 is connected to the lower end of the grip section 22. The external dimensions of the battery holding section 23 are larger than the external dimensions of the grip section 22 in both the front-rear and left-right directions.

[0057] The light holding portion 24 holds the light unit 14. The light holding portion 24 is fixed to the front of the battery holding portion 23 with a screw 5S. The light holding portion 24 may be considered as a part of the battery holding portion 23. The battery holding portion 23 may be considered as a first battery holding portion, and the light holding portion 24 may be considered as a second battery holding portion.

[0058] The rear cover 3 is made of synthetic resin. The rear cover 3 is disposed behind the motor accommodating portion 21. The rear cover 3 accommodates the fan 9. The rear cover 3 is disposed so as to cover an opening at the rear of the motor accommodating portion 21. The rear cover 3 is fixed to the motor accommodating portion 21 with screws 3S.

[0059] The motor accommodating portion 21 has an intake port 19A. The rear cover 3 has an exhaust port 19B. Air in the external space of the housing 2 flows into the internal space of the housing 2 through the intake port 19A. Air in the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 19B.

[0060] The casing 4 houses the power transmission mechanism 7. The casing 4 includes a first casing 4A and a second casing 4B. The second casing 4B is disposed in front of the first casing 4A. The mode switching ring 13 is disposed in front of the second casing 4B. The first casing 4A is made of synthetic resin. The second casing 4B is made of metal. In the embodiment, the second casing 4B is made of aluminum. The casing 4 is disposed in front of the motor accommodating section 21. Each of the first casing 4A and the second casing 4B is cylindrical.

[0061] The first casing 4A is fixed to the rear end of the second casing 4B. The opening at the rear end of the first casing 4A is covered by a bracket plate 4C. The opening at the front end of the second casing 4B is covered by a stop plate 4D. The stop plate 4D is fixed to the front end of the second casing 4B by screws 4E.

[0062] The casing 4 is disposed so as to cover the opening at the front of the motor accommodating portion 21. The first casing 4A is disposed inside the motor accommodating portion 21. The second casing 4B is fixed to the motor accommodating portion 21 with screws 4S.

[0063] The battery mounting section 5 is formed at the bottom of the battery holding section 23. The battery mounting section 5 is connected to the battery 20. The battery 20 is mounted to the battery mounting section 5. The battery 20 is detachable from the battery mounting section 5. The battery 20 includes a secondary battery. In the embodiment, the battery 20 includes a rechargeable lithium ion battery. When mounted to the battery mounting section 5, the battery 20 can supply power to the driver drill 1. The motor 6 is driven based on the power supplied from the battery 20. The interface panel 15 and the controller 18 operate based on the power supplied from the battery 20.

[0064] The motor 6 is a power source of the driver drill 1. The motor 6 is an inner rotor type brushless motor. The motor 6 is housed in the motor housing 21. The motor 6 has a cylindrical stator 61 and a rotor 62 disposed inside the stator 61. The rotor 62 includes a rotor shaft 63 extending in the axial direction. The rotor 62 is rotatable relative to the stator 61.

[0065] The power transmission mechanism 7 is disposed in front of the motor 6. The power transmission mechanism 7 is housed in the casing 4. The power transmission mechanism 7 connects the rotor shaft 63 and the output unit 8. The power transmission mechanism 7 transmits the power generated by the motor 6 to the output unit 8. The power transmission mechanism 7 has a plurality of gears.

[0066] The power transmission mechanism 7 includes a reduction mechanism 30 and a vibration mechanism 40 .

[0067] The reduction mechanism 30 reduces the rotation speed of the rotor shaft 63 and rotates the output section 8 at a lower rotation speed than the rotor shaft 63. In the embodiment, the reduction mechanism 30 has a first planetary gear mechanism 31, a second planetary gear mechanism 32, and a third planetary gear mechanism 33. The second planetary gear mechanism 32 is disposed in front of the first planetary gear mechanism 31. The third planetary gear mechanism 33 is disposed in front of the second planetary gear mechanism 32. The reduction mechanism 30 including the first planetary gear mechanism 31, the second planetary gear mechanism 32, and the third planetary gear mechanism 33 is disposed in front of the rotor 62. The gears of the first planetary gear mechanism 31, the second planetary gear mechanism 32, and the third planetary gear mechanism 33 are rotated by the rotor 62.

[0068] The vibration mechanism 40 vibrates the output portion 8 in the axial direction. The vibration mechanism 40 has a first cam 41, a second cam 42, and a vibration switching ring 43.

[0069] The output unit 8 (output shaft) is disposed forward of the motor 6. The output unit 8 rotates due to the rotational force of the motor 6. The output unit 8 rotates with the tool tip attached based on the rotational force transmitted from the motor 6 via the power transmission mechanism 7. The output unit 8 is disposed forward of a reduction mechanism 30 including a first planetary gear mechanism 31, a second planetary gear mechanism 32, and a third planetary gear mechanism 33, and is rotated by the reduction mechanism 30. The output unit 8 includes a spindle 81 that rotates about a rotation axis AX based on the rotational force transmitted from the motor 6, and a chuck 82 to which the tool tip is attached.

[0070] The fan 9 is disposed behind the motor 6. The fan 9 generates an airflow for cooling the motor 6. The fan 9 is fixed to at least a portion of the rotor 62. The fan 9 is fixed to a rear portion of the rotor shaft 63. The fan 9 rotates by the rotation of the rotor shaft 63. As the rotor shaft 63 rotates, the fan 9 rotates together with the rotor shaft 63. As the fan 9 rotates, air in the external space of the housing 2 flows into the internal space of the housing 2 through the intake port 19A. The air that has flowed into the internal space of the housing 2 cools the motor 6 by circulating through the internal space of the housing 2. The air that has circulated through the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 19B.

[0071] The trigger lever 10 is operated to start the motor 6. The trigger lever 10 is provided on the upper part of the grip portion 22. The front end of the trigger lever 10 protrudes forward from the front of the grip portion 22. The trigger lever 10 is movable in the front-rear direction. The trigger lever 10 is operated by an operator. When the trigger lever 10 is operated so as to move backward, a trigger signal is generated in the trigger signal generating circuit 17, and the motor 6 is started. When the operation of the trigger lever 10 is released, the motor 6 is stopped.

[0072] The forward / reverse switching lever 11 is operated to switch the rotation direction of the motor 6. The forward / reverse switching lever 11 is provided on the upper part of the grip portion 22. The left end of the forward / reverse switching lever 11 protrudes leftward from the left part of the grip portion 22. The right end of the forward / reverse switching lever 11 protrudes rightward from the right part of the grip portion 22. The forward / reverse switching lever 11 can move left and right. The forward / reverse switching lever 11 is operated by an operator. When the forward / reverse switching lever 11 is operated to move leftward, the motor 6 rotates in the forward direction. When the forward / reverse switching lever 11 is operated to move rightward, the motor 6 rotates in the reverse direction. When the rotation direction of the motor 6 is switched, the rotation direction of the spindle 81 is switched.

[0073] The speed switch lever 12 is operated to change the speed mode of the reduction mechanism 30. The speed switch lever 12 is provided on the upper part of the motor housing part 21. The speed switch lever 12 is movable in the forward and backward directions. The speed switch lever 12 is operated by an operator. The speed modes of the reduction mechanism 30 include a low speed mode and a high speed mode. The low speed mode refers to a speed mode in which the output part 8 is rotated at a low speed. The high speed mode refers to a speed mode in which the output part 8 is rotated at a high speed. When the speed switch lever 12 is operated to move forward, the speed mode of the reduction mechanism 30 is set to the low speed mode. When the speed switch lever 12 is operated to move backward, the speed mode of the reduction mechanism 30 is set to the high speed mode.

[0074] The mode switching ring 13 is operated to change the working mode of the vibration mechanism 40. The mode switching ring 13 is disposed in front of the casing 4. The mode switching ring 13 is rotatable. The mode switching ring 13 is operated by an operator. A mode detection ring 49 is provided which rotates integrally with the mode switching ring 13. The mode detection ring 49 is disposed inside the mode switching ring 13. A permanent magnet 49M is provided on the mode detection ring 49. The working modes of the vibration mechanism 40 include a vibration mode and a non-vibration mode. The vibration mode refers to a working mode in which the output unit 8 is vibrated in the axial direction. The non-vibration mode refers to a working mode in which the output unit 8 is not vibrated in the axial direction. The working mode of the vibration mechanism 40 is set to the vibration mode by operating the mode switching ring 13 to be disposed in the vibration mode position in the rotational direction. By manipulating the mode switching ring 13 so as to be disposed in the non-vibration mode position in the rotational direction, the working mode of the vibration mechanism 40 is set to the non-vibration mode.

[0075] The light unit 14 emits illumination light that illuminates the area in front of the driver drill 1. The light unit 14 includes, for example, a light emitting diode (LED). The light unit 14 and a light holding portion 24 that holds the light unit 14 are provided in the front of the battery holding portion 23. The light unit 14 may be considered to be disposed in the battery holding portion 23. The light unit 14 is disposed in the front of the battery holding portion 23.

[0076] A light opening 29 is provided in the light holding portion 24. The light opening 29 is formed in the front surface of the light holding portion 24 (the battery holding portion 23). At least a part of the light unit 14 is disposed in the light opening 29.

[0077] The interface panel 15 is provided in the battery holding section 23. The interface panel 15 includes an operating device 25A and a display device 25B. The interface panel 15 is plate-shaped. The operating device 25A includes an operation button. Examples of the display device 25B include a segment display including a plurality of segment light emitters, a flat panel display such as a liquid crystal display, and an indicator-type display in which a plurality of light-emitting diodes are arranged.

[0078] A panel opening 27 is formed in the battery holding portion 23. The panel opening 27 is formed in the upper surface of the battery holding portion 23, forward of the grip portion 22. At least a portion of the interface panel 15 is disposed in the panel opening 27.

[0079] The operating device 25A is operated to change the drive mode of the motor 6. The operating device 25A is operated by an operator. The drive modes of the motor 6 include a drill mode and a clutch mode. The drill mode refers to a drive mode in which the motor 6 is driven regardless of the torque acting on the motor 6 when the motor 6 is driven. The clutch mode refers to a drive mode in which the motor 6 is stopped when the torque acting on the motor 6 when the motor 6 is driven exceeds a torque threshold value.

[0080] The dial 16 is operated to change the driving conditions of the motor 6. The dial 16 is disposed on the right side of the front part of the battery holding part 23. The dial 16 is rotatable about a dial axis extending in the left-right direction. The dial 16 is rotatable 360° or more. The dial 16 is operated by an operator. The driving conditions of the motor 6 include a torque threshold. The dial 16 is operated to change the torque threshold in the clutch mode set by the operating device 25A.

[0081] A dial opening is formed in the battery holding portion 23. The dial opening is formed in the front portion of the battery holding portion 23. At least a portion of the dial 16 is disposed in the dial opening .

[0082] The controller 18 includes a computer system. The controller 18 outputs a control command to control the motor 6. At least a part of the controller 18 is housed in a controller case 26. The controller 18 is housed in a battery holding section 23 while being held in the controller case 26. The controller 18 includes a controller board 18A on which a plurality of electronic components are mounted. Examples of the electronic components mounted on the controller board 18A include a processor such as a CPU (Central Processing Unit), a non-volatile memory such as a ROM (Read Only Memory) or storage, a volatile memory such as a RAM (Random Access Memory), a transistor, a capacitor, and a resistor.

[0083] The controller 18 sets the drive conditions of the motor 6 based on the operation of the dial 16. As described above, the drive conditions of the motor 6 include a torque threshold. In the clutch mode, the controller 18 sets the torque threshold based on the operation of the dial 16.

[0084] Furthermore, in the clutch mode, the controller 18 stops the motor 6 when the torque acting on the motor 6 during driving of the motor 6 exceeds a set torque threshold value.

[0085] Furthermore, the controller 18 causes the display device 25B to display the set drive conditions of the motor 6. The controller 18 causes the display device 25B to display the set torque threshold value.

[0086] [Motor and power transmission mechanism] Fig. 4 is a cross-sectional view showing an upper portion of the driver drill 1 according to the embodiment. As shown in Fig. 4, the motor 6 has a cylindrical stator 61 and a rotor 62 disposed inside the stator 61. The rotor 62 includes a rotor shaft 63 extending in the axial direction.

[0087] The stator 61 includes a stator core 61A including a plurality of laminated steel plates, a front insulator 61B disposed in front of the stator core 61A, a rear insulator 61C disposed in the rear of the stator core 61A, a plurality of coils 61D wound around the stator core 61A via the front insulator 61B and the rear insulator 61C, a sensor circuit board 61E attached to the front insulator 61B, a fusing terminal 61F connected to the coils 61D, and a short-circuit member 61G supported by the front insulator 61B. The sensor circuit board 61E includes a plurality of rotation detection elements for detecting the rotation of the rotor 62. The short-circuit member 61G connects the plurality of coils 61D via the fusing terminal 61F. The short-circuit member 61G is connected to the controller 18 via a lead wire.

[0088] The rotor 62 rotates about a rotation axis AX. The rotor 62 has a rotor shaft 63, a rotor core 62A arranged around the rotor shaft 63, and a plurality of permanent magnets 62B held by the rotor core 62A. The rotor core 62A is cylindrical. The rotor core 62A includes a plurality of laminated steel plates. The rotor core 62A has a through hole extending in the axial direction. A plurality of through holes are formed in the circumferential direction. The permanent magnets 62B are arranged in each of the plurality of through holes of the rotor core 62A.

[0089] The rotation detection element of the sensor circuit board 61E detects the magnetic field of the permanent magnet 62B, thereby detecting the rotation of the rotor 62. The controller 18 supplies a drive current to the coil 61D based on the detection data of the rotation detection element.

[0090] The rotor shaft 63 rotates about a rotation axis AX. The rotation axis AX of the rotor shaft 63 coincides with the rotation axis of the output section 8. A front portion of the rotor shaft 63 is rotatably supported by a bearing 64. A rear portion of the rotor shaft 63 is rotatably supported by a bearing 65. The bearing 64 is held by a bracket plate 4C disposed in front of the stator 61. The bearing 65 is held by the rear cover 3. A front end portion of the rotor shaft 63 is disposed forward of the bearing 64. A front end portion of the rotor shaft 63 is disposed in the internal space of the casing 4.

[0091] A pinion gear 31S is provided at the front end of the rotor shaft 63. The rotor shaft 63 is connected to the first planetary gear mechanism 31 of the reduction mechanism 30 via the pinion gear 31S.

[0092] The first planetary gear mechanism 31 has a plurality of planetary gears 31P arranged around the pinion gear 31S, a first carrier 31C supporting the plurality of planetary gears 31P, and an internal gear 31R arranged around the plurality of planetary gears 31P. Gears are provided on the outer periphery of the first carrier 31C.

[0093] The second planetary gear mechanism 32 has a sun gear 32S, a plurality of planetary gears 32P arranged around the sun gear 32S, a second carrier 32C supporting the plurality of planetary gears 32P, and an internal gear 32R arranged around the plurality of planetary gears 32P. The sun gear 32S is arranged in front of the first carrier 31C. The diameter of the sun gear 32S is smaller than the diameter of the first carrier 31C. The first carrier 31C and the sun gear 32S are integral. The first carrier 31C and the sun gear 32S rotate together.

[0094] The third planetary gear mechanism 33 has a sun gear 33S, a plurality of planetary gears 33P arranged around the sun gear 33S, a third carrier 33C supporting the plurality of planetary gears 33P, and an internal gear 33R arranged around the plurality of planetary gears 33P. The sun gear 33S is arranged in front of the second carrier 32C.

[0095] The speed reduction mechanism 30 also has a speed change ring 34 connected to the speed change lever 12, and a connecting ring 35 arranged in front of the speed change ring 34. The connecting ring 35 is fixed to the inner surface of the first casing 4A. A gear is provided on the inner periphery of the connecting ring 35. The speed change ring 34 has a protrusion 34T that protrudes upward. Coil springs 36 are arranged in front of and behind the protrusion 34T. The speed change ring 34 is connected to the speed change lever 12 via the coil spring 36.

[0096] The speed change ring 34 switches between a low-speed mode and a high-speed mode. The speed change ring 34 is connected to the internal gear 32R. The speed change lever 12 is connected to the internal gear 32R via the speed change ring 34. The speed change lever 12, the speed change ring 34, and the internal gear 32R can move together. When the speed change lever 12 is operated by an operator, the speed change ring 34 moves in the front-rear direction inside the first casing 4A. The speed change ring 34 switches between the low-speed mode and the high-speed mode by moving in the front-rear direction between a low-speed mode position and a high-speed mode position rearward of the low-speed mode position while the internal gear 32R and the planetary gear 32P are engaged. When the speed change lever 12 is operated, the low-speed mode and the high-speed mode are switched.

[0097] When the internal gear 32R is disposed in the low speed mode position, it comes into contact with the coupling ring 35. The internal gear 32R comes into contact with the coupling ring 35, thereby restricting the rotation of the internal gear 32R. When the internal gear 32R is disposed in the high speed mode position, it moves away from the coupling ring 35. The internal gear 32R moves away from the coupling ring 35, thereby allowing the internal gear 32R to rotate.

[0098] Furthermore, the internal gear 32R meshes with the planetary gear 32P when placed in the low speed mode position. The internal gear 32R meshes with both the planetary gear 32P and the first carrier 31C when placed in the high speed mode position.

[0099] When the internal gear 32R is disposed in the low speed mode position, the rotor shaft 63 rotates by being driven by the motor 6, so that the pinion gear 31S rotates and the planetary gear 31P revolves around the pinion gear 31S. The revolution of the planetary gear 31P causes the first carrier 31C and the sun gear 32S to rotate at a rotational speed lower than the rotational speed of the rotor shaft 63. When the sun gear 32S rotates, the planetary gear 32P revolves around the sun gear 32S. The revolution of the planetary gear 32P causes the second carrier 32C and the sun gear 33S to rotate at a rotational speed lower than the rotational speed of the first carrier 31C. In this manner, when the internal gear 32R is positioned in the low speed mode position and the motor 6 is driven, both the speed reduction function of the first planetary gear mechanism 31 and the speed reduction function of the second planetary gear mechanism 32 are exerted, and the second carrier 32C and the sun gear 33S rotate in the low speed mode.

[0100] When the rotor shaft 63 rotates by the drive of the motor 6 while the internal gear 32R is disposed in the high speed mode position, the pinion gear 31S rotates and the planetary gear 31P revolves around the pinion gear 31S. Due to the revolution of the planetary gear 31P, the first carrier 31C and the sun gear 32S rotate at a rotation speed lower than the rotation speed of the rotor shaft 63. Since the internal gear 32R meshes with both the planetary gear 32P and the first carrier 31C while the internal gear 32R is disposed in the high speed mode position, the internal gear 32R and the first carrier 31C rotate together. Due to the rotation of the internal gear 32R, the planetary gear 32P revolves at the same revolution speed as the rotation speed of the internal gear 32R. Due to the revolution of planetary gear 32P, second carrier 32C and sun gear 33S rotate at the same rotational speed as that of first carrier 31C. In this manner, when motor 6 is driven in a state in which internal gear 32R is disposed in the high speed mode position, the speed reduction function of first planetary gear mechanism 31 is exerted but the speed reduction function of second planetary gear mechanism 32 is not exerted, and second carrier 32C and sun gear 33S rotate in the high speed mode.

[0101] When second carrier 32C and sun gear 33S rotate, planetary gear 33P revolves around sun gear 33S. The revolution of planetary gear 33P rotates third carrier 33C.

[0102] The spindle 81 is connected to the third carrier 33C via a lock cam 85. The spindle 81 is splined to the lock cam 85. The lock cam 85 is rotatably supported by a lock ring 86. The lock ring 86 is disposed inside the second casing 4B. The lock ring 86 is fixed to the second casing 4B. The spindle 81 rotates due to the rotation of the third carrier 33C.

[0103] The spindle 81 is rotatably supported by a bearing 83 and a bearing 84. While being supported by the bearings 83 and 84, the spindle 81 is movable in the front-rear direction.

[0104] The spindle 81 has a flange portion 81F. A coil spring 87 is disposed between the flange portion 81F and the bearing 83. The coil spring 87 generates an elastic force that moves the spindle 81 forward.

[0105] The chuck 82 is capable of holding a tool bit. The chuck 82 is connected to the front part of the spindle 81. The chuck 82 rotates as the spindle 81 rotates. The chuck 82 rotates while holding the tool bit.

[0106] The first cam 41 and the second cam 42 of the vibration mechanism 40 are disposed inside the second casing 4B. The first cam 41 and the second cam 42 are disposed between the bearing 83 and the bearing 84 in the front-rear direction.

[0107] The first cam 41 is ring-shaped. The first cam 41 is disposed around the spindle 81. The first cam 41 is fixed to the spindle 81. The first cam 41 rotates together with the spindle 81. Cam teeth are provided on the rear surface of the first cam 41. The first cam 41 is supported by a stop ring 44. The stop ring 44 is disposed around the spindle 81. In the front-rear direction, the stop ring 44 is disposed between the first cam 41 and the bearing 83. The elastic force of the coil spring 87 causes the stop ring 44 to contact the rear surface of the bearing 83.

[0108] The second cam 42 is ring-shaped. The second cam 42 is disposed behind the first cam 41. The second cam 42 is disposed around the spindle 81. The second cam 42 is rotatable relative to the spindle 81. Cam teeth are provided on a front surface of the second cam 42. The cam teeth on the front surface of the second cam 42 mesh with the cam teeth on the rear surface of the first cam 41. A pawl is provided on the rear surface of the second cam 42.

[0109] A support ring 45 is disposed between the second cam 42 and the bearing 84 in the front-rear direction. The support ring 45 is disposed inside the second casing 4B. The support ring 45 is fixed to the second casing 4B. A plurality of steel balls 46 are disposed on the front side of the support ring 45. A washer 47 is disposed between the steel balls 46 and the second cam 42. The second cam 42 is rotatable in a space defined by the small diameter portion 402 and the washer 47 with its front-rear movement restricted.

[0110] The vibration switching ring 43 switches between a vibration mode and a non-vibration mode. The mode switching ring 13 is connected to the vibration switching ring 43 via a cam ring 48. The mode switching ring 13 and the cam ring 48 can rotate together. The vibration switching ring 43 can move in the front-rear direction. The vibration switching ring 43 has a protrusion 43T. The protrusion 43T is inserted into a guide hole provided in the second casing 4B. The vibration switching ring 43 can move in the front-rear direction while being guided by the guide hole provided in the second casing 4B. The rotation of the vibration switching ring 43 is restricted by the protrusion 43T. When the mode switching ring 13 is operated by an operator, the vibration switching ring 43 moves in the front-rear direction. The vibration switching ring 43 switches between the vibration mode and the non-vibration mode by moving in the front-rear direction between a forward position and a backward position that is further rearward than the forward position. By operating the mode switching ring 13, the vibration mode and the non-vibration mode can be switched.

[0111] The vibration mode includes a state in which the rotation of the second cam 42 is restricted. The non-vibration mode includes a state in which the rotation of the second cam 42 is permitted. When the vibration switching ring 43 moves to the forward position, the rotation of the second cam 42 is restricted. When the vibration switching ring 43 moves to the backward position, the rotation of the second cam 42 is permitted.

[0112] In the vibration mode, at least a part of the vibration switching ring 43 that has moved to the forward position comes into contact with the second cam 42. The contact between the vibration switching ring 43 and the second cam 42 restricts the rotation of the second cam 42. When the motor 6 is driven in a state in which the rotation of the second cam 42 is restricted, the first cam 41 fixed to the spindle 81 rotates while contacting the cam teeth of the second cam 42. As a result, the spindle 81 rotates while vibrating in the front-rear direction.

[0113] In the non-vibration mode, the vibration switching ring 43, which has moved to the retracted position, moves away from the second cam 42. The movement of the vibration switching ring 43 and the second cam 42 away from each other allows the second cam 42 to rotate. When the motor 6 is driven in a state in which the rotation of the second cam 42 is allowed, the second cam 42 rotates together with the first cam 41 and the spindle 81. As a result, the spindle 81 rotates without vibrating in the front-rear direction.

[0114] The vibration switching ring 43 is disposed around the first cam 41 and the second cam 42. The vibration switching ring 43 also has a facing portion 43S that faces the rear surface of the second cam 42. The facing portion 43S protrudes from the rear of the vibration switching ring 43 radially inward.

[0115] When the mode switching ring 13 is operated and the vibration switching ring 43 moves to the forward position, the claw on the rear surface of the second cam 42 comes into contact with the opposing portion 43S of the vibration switching ring 43. This restricts the rotation of the second cam 42. In this manner, when the mode switching ring 13 is operated and the vibration switching ring 43 moves to the forward position, the vibration mechanism 40 is switched to the vibration mode.

[0116] When the mode switching ring 13 is operated and the vibration switching ring 43 moves to the retracted position, the opposing portion 43S of the vibration switching ring 43 moves away from the second cam 42. This allows the second cam 42 to rotate. In this manner, when the mode switching ring 13 is operated and the vibration switching ring 43 moves to the retracted position, the vibration mechanism 40 is switched to the non-vibration mode.

[0117] [Light unit] Fig. 5 is a cross-sectional view showing the light unit 14 according to the embodiment. Fig. 6 is a perspective view showing the light unit 14 according to the embodiment.

[0118] The light unit 14 emits illumination light. The light unit 14 illuminates the tip of the bit attached to the output portion 8 and the periphery of the bit with the illumination light. The light unit 14 illuminates the front end side of the output portion 8 with the illumination light. The light unit 14 illuminates a work target of the driver drill 1 with the illumination light.

[0119] The light unit 14 is disposed in front of the battery holding portion 23. In the embodiment, a light holding portion 24 that holds the light unit 14 is disposed in front of the battery holding portion 23.

[0120] The light unit 14 includes chip-on-board light emitting diodes 50 (COB LEDs) and an optical member 57. In the embodiment, the chip-on-board light emitting diodes 50 are appropriately referred to as COB lights 50.

[0121] The COB light 50 has a substrate 51, a plurality of LED elements 52 which are light-emitting elements, a bank 54, and a phosphor 55. Examples of the substrate 51 include an aluminum substrate, a glass cloth-based epoxy resin substrate (FR-4 substrate), and a composite substrate epoxy resin substrate (CEM-3 substrate). The LED elements 52 and the substrate 51 are connected via gold wires (not shown). The gold wires connect the plurality of LED elements 52 to each other. The bank 54 is provided on the surface of the substrate 51. The bank 54 is disposed around the LED elements 52. The bank 54 defines a partitioned space in which the phosphor 55 is disposed. A pair of electrodes (not shown) are disposed on the surface (front surface) of the substrate 51 outside the bank 54. The electrodes may be disposed on the back surface (rear surface) of the substrate 51. One of the pair of electrodes is a positive electrode, and the other is a negative electrode. Power output from the battery 20 is supplied to the electrodes. The power supplied to the electrodes is supplied to the LED element 52 via the substrate 51 and the gold wires. The LED element 52 emits light based on the power supplied from the battery 20.

[0122] The substrate 51 has a rectangular shape that is long in the left-right direction. The LED elements 52 are mounted on the surface (front surface) of the substrate 51. The LED elements 52 are arranged at intervals in the left-right direction. In the embodiment, four LED elements 52 are arranged at equal intervals in the left-right direction.

[0123] The bank is provided on the front surface of the substrate 51. The bank protrudes forward from the front surface of the substrate 51. The bank is annular. The LED elements 52 are disposed inside the bank .

[0124] The phosphor 55 is disposed on the front surface of the substrate 51. The phosphor 55 is disposed inside the bank 54 so as to cover each of the LED elements 52.

[0125] A pair of lead wires (not shown) are connected to the substrate 51. The electrodes described above are connected to the lead wires. The current output from the battery 20 is supplied to the electrodes via the controller 18 and the lead wires. The voltage of the battery 20 is applied to the electrodes. The current supplied to the electrodes is supplied to the LED element 52 via the substrate 51 and gold wires. The LED element 52 emits light based on the current supplied from the battery 20.

[0126] The optical member 57 is connected to the COB light 50. The optical member 57 is fixed to the substrate 51. The optical member 57 is made of polycarbonate resin. In the embodiment, the optical member 57 is made of polycarbonate resin containing a white diffusing agent. The optical member 57 is milky white. The light transmittance of the optical member 57 is 40% or more and 70% or less. Since the optical member 57 is milky white, the outline of the LED element 52 is difficult to see from the outside of the impact tool 1. Since the outline of the LED element 52 is difficult to see, the design of the impact tool 1 is improved.

[0127] At least a part of the optical member 57 is disposed forward of the COB light 50. It is disposed in the light opening 29 provided in the light holding part 24. As described above, when the light holding part 24 and the battery holding part 23 are regarded as one body, the optical member 57 is disposed in the light opening 29 provided in the battery holding part 23. The optical member 57 has a light transmitting part 57A, an upper surrounding part 57B, a lower surrounding part 57C, an upper convex part 57D, and a lower convex part 57E.

[0128] The light transmitting portion 57A is disposed in front of the COB light 50. Light emitted from the COB light 50 passes through the light transmitting portion 57A. The light transmitting portion 57A is disposed in front of the LED element 52. The light transmitting portion 57A faces the LED element 52. The light emitted from the LED element 52 passes through the light transmitting portion 57A and is irradiated to the front of the light unit 14.

[0129] The light transmitting portion 57A has an incident surface 57G into which light from the LED element 52 of the COB light 50 enters, and an exit surface 57H from which the light from the incident surface 57G exits. The front surface of the substrate 51 faces the incident surface 57G of the light transmitting portion 57A. The incident surface 57G faces the LED element 52. The incident surface 57G faces substantially backward. The exit surface 57H faces substantially forward.

[0130] The upper surrounding portion 57B extends rearward from the upper end of the light transmitting portion 57A. The upper convex portion 57D protrudes upward from the front of the upper surrounding portion 57B. The lower surrounding portion 57C extends rearward from the lower end of the light transmitting portion 57A. The lower convex portion 57E protrudes downward from the rear of the lower surrounding portion 57C.

[0131] A total reflection surface 57F is disposed on the upper convex portion 57D. The total reflection surface 57F is disposed above the incident surface 57G. The total reflection surface 57F totally reflects the light from the LED element 52 of the COB light 50 forward. The exit surface 57H exits the light from the incident surface 57G and the light from the total reflection surface 57F.

[0132] The substrate 51 is held by the light holding part 24 via an optical member 57. The substrate 51 is held by the light holding part 24 in a state inclined with respect to the rotation axis AX of the motor 6. The angle between the rotation axis AX of the motor 6 and a normal line to the front surface of the substrate 51 is equal to or greater than 5 degrees and equal to or less than 20 degrees. In the embodiment, the angle between the rotation axis AX of the motor 6 and a normal line to the front surface of the substrate 51 is 10 degrees.

[0133] [controller] Each of Figures 7 and 8 is a block diagram showing a driver drill 1 according to an embodiment. Figure 7 shows a first circuit configuration of the driver drill 1. Figure 8 shows a second circuit configuration of the driver drill 1. As shown in Figures 7 and 8, the driver drill 1 has a battery 20, a controller board 18A, and a board 51 (LED board). A power supply circuit 18B, a control circuit 18C, and a constant current circuit 18D are provided on the board 51. An LED circuit 53 is provided on the board 51.

[0134] The power supply circuit 18B adjusts at least the voltage applied from the battery 20 to the control circuit 18C. In the first circuit configuration 91 shown in FIG. 7, the power supply circuit 18B is not present between the battery 20 and the LED circuit 53. In the first circuit configuration 91, the voltage of the battery 20 is applied to the control circuit 18C after being stepped down to, for example, 5V by the power supply circuit 18B. In the first circuit configuration 91, the voltage of the battery 20 is applied to the COB light 50 via the LED circuit 53 without being stepped down. In the second circuit configuration 92 shown in FIG. 8, the voltage of the battery 20 is applied to each of the control circuit 18C and the LED circuit 53 after being stepped down to, for example, 5V by the power supply circuit 18B. In the embodiment, the first circuit configuration 91 or the second circuit configuration 92 is adopted as the circuit configuration of the driver drill 1.

[0135] The control circuit 18C controls ON / OFF of the COB light 50. The control circuit 18C turns on or off the LED element 52. The constant current circuit 18D controls the current supplied to the LED circuit 53.

[0136] 9 is a diagram showing LED elements 52 mounted on a substrate 51 according to an embodiment. The substrate 51 is long in the left-right direction. Four LED elements 52 are mounted on the front surface of the substrate 51 at intervals in the left-right direction. In the following description, the LED element 52 arranged on the rightmost side of the four LED elements 52 will be appropriately referred to as LED1, the LED element 52 arranged next to the right of LED1 will be appropriately referred to as LED3, the LED element 52 arranged next to the right of LED3 will be appropriately referred to as LED4, and the LED element 52 arranged on the leftmost side will be appropriately referred to as LED2.

[0137] 10 is a diagram showing the entire circuit configuration of an LED circuit 53 according to an embodiment in which there are four LED elements 52. LED1, LED2, LED3, and LED4 are mounted on a substrate 51. Resistors R1, R2, and R3 can also be mounted on the substrate 51.

[0138] 11 and 12 are diagrams showing the circuit configuration of an LED circuit 53 in the case where the number of LED elements 52 according to the embodiment is four. LED1, LED2, LED3, and LED4 are mounted on a substrate 51. Resistors R1, R2, and R3 can be mounted on the substrate 51. As described with reference to FIG. 10, the positions of LED1, LED2, LED3, and LED4 are fixed on the substrate 51. In the manufacturing process of the COB light 50, as shown in FIG. 11, the resistor R2 is mounted on the substrate 51, and the resistors R1 and R2 are not mounted on the substrate 51, so that LED1, LED2, LED3, and LED4 are connected in series. As shown in FIG. 12, the resistors R1 and R3 are mounted on the substrate 51, and the resistor R2 is not mounted on the substrate 51, so that the first group of LED elements 52 including LED1 and LED2 are connected in series, and the second group of LED elements 52 including LED3 and LED4 are connected in series.

[0139] In the manufacturing process of the COB light 50, either the first circuit configuration 91 or the second circuit configuration 92 is selected based on the rated voltage of the battery 20 to be mounted in the battery mounting section 5. Also, based on the rated voltage of the battery 20 to be mounted in the battery mounting section 5, either the series connection of the four LED elements 52 or the parallel connection of the first group of LED elements 52 (LED1, LED2) and the second group of LED elements 52 (LED3, LED4) is selected as described with reference to Figs.

[0140] For example, when the rated voltage of the battery 20 mounted on the battery mounting unit 5 is 18 V, the first circuit configuration 91 is selected. When the rated voltage of the battery 20 mounted on the battery mounting unit 5 is 36 V, the second circuit configuration 92 is selected.

[0141] Fig. 13 is a diagram showing LED elements 52 mounted on a substrate 51 according to an embodiment. In the example shown in Fig. 13, six LED elements 52 are mounted on the front surface of the substrate 51 at intervals in the left-right direction. In the following description, the LED element 52 arranged on the rightmost side among the six LED elements 52 is appropriately referred to as LED1, the LED element 52 arranged next to the right side of LED1 is appropriately referred to as LED3, the LED element 52 arranged next to the right side of LED3 is appropriately referred to as LED5, the LED element 52 arranged next to the right side of LED5 is appropriately referred to as LED6, the LED element 52 arranged next to the right side of LED6 is appropriately referred to as LED4, and the LED element 52 arranged on the leftmost side among the six LED elements 52 is appropriately referred to as LED2.

[0142] 14 is a diagram showing the entire circuit configuration of an LED circuit 53 according to an embodiment in which there are six LED elements 52. LED1, LED2, LED3, LED4, LED5, and LED6 are mounted on a substrate 51. Resistors R1, R2, R3, R4, R5, and R6 can also be mounted on the substrate 51.

[0143] 15 and 16 are diagrams showing the circuit configuration of an LED circuit 53 in the case where there are six LED elements 52 according to the embodiment. LED1, LED2, LED3, LED4, LED5, and LED6 are mounted on a substrate 51. Resistors R1, R2, R3, R4, R5, and R6 can be mounted on the substrate 51. As described with reference to FIG. 14, the positions of LED1, LED2, LED3, LED4, LED5, and LED6 are fixed on the substrate 51. In the manufacturing process of the COB light 50, as shown in FIG. 15, resistors R2 and R5 are mounted on the substrate 51, and resistors R1, R3, R4, and R6 are not mounted on the substrate 51, so that LED1, LED2, LED3, LED4, LED5, and LED6 are connected in series. As shown in FIG. 16, resistors R1, R3, R4, and R6 are not mounted on substrate 51, so that a first group of LED elements 52 including LED1 and LED2 are connected in series, a second group of LED elements 52 including LED3 and LED4 are connected in series, and a third group of LED elements 52 including LED5 and LED6 are connected in series.

[0144] In the manufacturing process of the COB light 50, either the first circuit configuration 91 or the second circuit configuration 92 is selected based on the rated voltage of the battery 20 to be mounted in the battery mounting section 5. Also, based on the rated voltage of the battery 20 to be mounted in the battery mounting section 5, either the series connection of six LED elements 52 or the parallel connection of the first group of LED elements 52 (LED1, LED2), the second group of LED elements 52 (LED3, LED4), and the third group of LED elements 52 (LED5, LED6) as described with reference to Figs. 15 and 16 is selected.

[0145] For example, when the rated voltage of the battery 20 mounted on the battery mounting unit 5 is 18 V, the first circuit configuration 91 is selected. When the rated voltage of the battery 20 mounted on the battery mounting unit 5 is 36 V, the second circuit configuration 92 is selected.

[0146] By preparing one type of substrate 51 in advance as described with reference to FIG. 10 or FIG. 14, it is selected whether to connect the multiple LED elements 52 in series or in parallel during the manufacturing stage of the COB light 50 based on the rated voltage of the battery 20.

[0147] For example, when six LED elements 52 are connected in series, the first circuit configuration 91 is selected. When the first group of LED elements 52, the second group of LED elements 52, and the third group of LED elements 52 are connected in parallel, the second circuit configuration 92 is selected.

[0148] When the rated voltage of the battery 20 held in the battery holding portion 23 of the housing 2 is 25.2V or more, the first circuit configuration 91 may be adopted, or the second circuit configuration 92 may be adopted. When the rated voltage of the battery 20 is 25.2V or more and the number of LED elements 52 is four, the four LED elements 52 may be connected in series, or the first group of LED elements 52 and the second group of LED elements 52 may be connected in parallel. When the rated voltage of the battery 20 is 25.2V or more and the number of LED elements 52 is six, the six LED elements 52 may be connected in series, or the first group of LED elements 52, the second group of LED elements 52, and the third group of LED elements 52 may be connected in parallel. The rated voltage of the battery 20 may be 36V or 40V.

[0149] When the rated voltage of the battery 20 held in the battery holding portion 23 of the housing 2 is 21.6 V or more, it is preferable to employ the first circuit configuration 91. When the rated voltage of the battery 20 is 21.6 V or more and there are six LED elements 52, it is preferable that the six LED elements 52 are connected in series.

[0150] [effect] As described above, in the embodiment, the driver drill 1 comprises a motor 6 having a stator 61 and a rotor 62 rotatable relative to the stator 61, an output section 8 arranged forward of the motor 6 and rotated by the motor 6, a motor accommodating section 21 that accommodates the motor 6, a grip section 22 arranged below the motor accommodating section 21, a battery holding section 23 arranged below the grip section 22, and a COB light 50 arranged in the battery holding section 23.

[0151] In the above configuration, high-intensity light is emitted from the COB light 50 located below the grip portion 22. This brightly illuminates the work target. In addition, the shadow of the tool tip is less likely to be cast on the work target. This makes it easier for the worker to see the work target.

[0152] In the embodiment, the COB light 50 is disposed in front of the battery holding portion 23 .

[0153] In the above configuration, the work target in front of the battery holding portion 23 is brightly illuminated.

[0154] In the embodiment, the COB light 50 has a substrate 51 and an LED element 52 mounted on the front surface of the substrate 51. The substrate 51 is long in the left-right direction.

[0155] The above configuration allows illumination of a wide range of the work subject.

[0156] In this embodiment, a plurality of LED elements 52 are mounted at intervals in the left-right direction.

[0157] In the above configuration, even if a part of the light emitted from the LED element 52 is irradiated onto the tool tip, the LED elements 52 are mounted at intervals in the left-right direction, so the shadows of the tool tip cancel each other out. As a result, the shadows cast on the work object become less noticeable. This makes it easier for the worker to see the work object.

[0158] In the embodiment, the driver drill 1 includes an optical member 57 that is disposed forward of the COB light 50 and has a light transmitting portion 57A through which the light emitted from the COB light 50 passes.

[0159] In the above configuration, the light transmitted through the optical member 57 is irradiated onto the work target.

[0160] In the embodiment, the optical member 57 is disposed in the light opening 29 provided in the battery holding portion 23 .

[0161] In the above configuration, the light transmitted through the optical member 57 is irradiated onto the work object without any loss.

[0162] In this embodiment, the optical member 57 is made of polycarbonate resin containing a white diffusing agent.

[0163] In the above configuration, optical member 57 is milky white, making it difficult to visually recognize the outline of elements such as LED element 52 of COB light 50 from the outside of driver drill 1. Since the outline of the elements is difficult to visually recognize, the design of driver drill 1 is improved.

[0164] In the embodiment, the light transmittance of the optical member 57 is not less than 40% and not more than 70%.

[0165] In the above configuration, the outer shape of the element of the COB light 50 is difficult to see from the outside of the driver drill 1. Since the outer shape of the element is difficult to see, the design of the driver drill 1 is improved.

[0166] In the embodiment, the optical member 57 has an incident surface 57G on which light from the COB light 50 is incident, a total reflection surface 57F that totally reflects the light from the COB light 50, and an exit surface 57H that emits light from the incident surface 57G and the light from the total reflection surface 57F.

[0167] In the above configuration, even if a portion of the light emitted from the COB light 50 does not enter the incident surface 57G of the light transmitting portion 57A, it is reflected by the total reflection surface 57F and emitted from the exit surface 57H, thereby reducing the loss of light emitted from the COB light 50.

[0168] In the embodiment, total reflection surface 57F is disposed above entrance surface 57G.

[0169] In the above configuration, even if a portion of the light emitted from the COB light 50 travels above the light transmitting portion 57A, it is reflected by the total reflection surface 57F and emitted from the emission surface 57H, thereby reducing the loss of the light emitted from the COB light 50.

[0170] In the embodiment, the optical member 57 has an upper surrounding portion 57B extending rearward from the upper end of the light transmitting portion 57A, and an upper convex portion 57D protruding upward from the upper surrounding portion 57B. The total reflection surface 57F is disposed on the upper convex portion 57D.

[0171] In the above configuration, the upper convex portion 57D having the total reflection surface 57F can function as a positioning portion for the optical member 57 relative to the battery holding portion .

[0172] In the embodiment, the optical member 57 has a lower surrounding portion 57C extending rearward from the lower end of the light transmitting portion 57A, and a lower convex portion 57E protruding downward from the lower surrounding portion 57C.

[0173] In the above configuration, the lower convex portion 57E can function as a positioning portion for the optical member 57 with respect to the battery holding portion 23. In addition, the upper convex portion 57D and the lower convex portion 57E can function as rotation stoppers for the optical member 57 with respect to the battery holding portion 23.

[0174] In the embodiment, the COB light 50 has a substrate 51 and an LED element 52 mounted on the front surface of the substrate 51. The angle between the rotation axis AX of the motor 6 and the normal to the front surface of the substrate 51 is equal to or greater than 5 degrees and equal to or less than 20 degrees.

[0175] With the above-described configuration, the work target can be properly illuminated with the tool bit at the center.

[0176] In the embodiment, the COB light 50 has a substrate 51 and an LED element 52 mounted on the front surface of the substrate 51. At least four LED elements 52 are mounted at intervals in the left-right direction. A first group of LED elements 52 including a first LED element 52 and a second LED element 52 are connected in series, a second group of LED elements 52 including a third LED element 52 and a fourth LED element 52 are connected in series, and the first group of LED elements 52 and the second group of LED elements 52 are connected in parallel. The second group of LED elements 52 is disposed between the first LED element 52 and the second LED element 52 in the left-right direction.

[0177] In the above configuration, even if an imbalance in the current supplied to the COB light 50 causes an imbalance in the luminous intensity of the light emitted from the first group of LED elements 52 and the luminous intensity of the light emitted from the second group of LED elements 52, the difference in illuminance between the left and right sides of the work object can be reduced.

[0178] In the embodiment, the third group of LED elements 52 including the fifth LED element 52 and the sixth LED element 52 are connected in series, the first group of LED elements 52, the second group of LED elements 52 and the third group of LED elements 52 are connected in parallel, and in the left-right direction, the second group of LED elements 52 are arranged between the first LED element 52 and the second LED element 52, and the third group of LED elements 52 are arranged between the third LED element 52 and the fourth LED element 52.

[0179] In the above configuration, even if an imbalance in the current supplied to the COB light 50 causes an imbalance in the luminous intensity of the light emitted from the first group of LED elements 52 and the luminous intensity of the light emitted from the second group of LED elements 52, the illuminance on the work object can be made uniform.

[0180] In the embodiment, the driver drill 1 includes a motor 6 having a stator 61 and a rotor 62 rotatable relative to the stator 61, an output unit 8 rotated by the rotor 62, a housing 2 accommodating the motor 6, and a COB light 50 disposed in the housing 2. The rated voltage of the battery 20 held in the battery holding portion 23 of the housing 2 is 25.2 V or higher.

[0181] In the above configuration, the COB light 50 can be driven at a high voltage, so the work target is brightly illuminated, making it easier for the worker to see the work target.

[0182] In the embodiment, the driver drill 1 includes a motor 6 having a stator 61 and a rotor 62 rotatable relative to the stator 61, an output unit 8 rotated by the rotor 62, a housing 2 accommodating the motor 6, and a COB light 50 disposed in the housing 2. The rated voltage of the battery 20 held in the battery holding portion 23 of the housing 2 is 21.6 V or higher, and the voltage of the battery 20 is applied to the COB light 50 without being stepped down.

[0183] In the above configuration, the COB light 50 can be driven at a high voltage, so the work target is brightly illuminated, making it easier for the worker to see the work target.

[0184] In the embodiment, the COB light 50 has a substrate 51 and an LED element 52 mounted on the substrate 51. At least six LED elements 52 are mounted. The at least six LED elements 52 are connected in series.

[0185] In the above configuration, the work target is brightly illuminated by at least six LED elements 52 connected in series, making it easier for the worker to visually recognize the work target.

[0186] [Other embodiments] Fig. 17 is a perspective view showing an optical member 570 according to another embodiment. Fig. 18 is an enlarged view of a portion of an optical member 570 according to another embodiment. As shown in Figs. 17 and 18, a plurality of convex portions 570T may be provided on an emission surface 570H of the optical member 570. The plurality of convex portions 570T are provided with no gaps between them. The height of the convex portions 570T is about 0.1 mm. The optical member 570 does not contain a diffusing agent.

[0187] There is little loss of illuminance because the optical member 570 does not contain a diffusing agent, making it possible to brightly illuminate the work target and improving visibility.

[0188] By providing the uneven shape on the light exit surface 570H, the light can be diffused on the light exit surface 570H, and the shadow of the bit can be blurred. This increases the uniformity of the work object and improves visibility. In addition, since the pattern of the board 51 cannot be seen from the outside, the design is good.

[0189] Furthermore, since optical member 570 does not contain a diffusing agent, the degree of diffusion can be changed simply by changing the dimensions of the projections and recesses.

[0190] The shape of the optical member 570 is not limited to a rectangle, and may be a circular COB or other shape.

[0191] If the height of the convex portion 570T is less than 0.05 mm, the degree of diffusion is small and the substrate 51 is easily visible from the outside, so the height of the convex portion 570T needs to be 0.1 mm or more. If the height of the convex portion 570T is 0.3 mm or more, stray light increases, resulting in a large loss of illuminance.

[0192] Since the optical member 570 does not contain a diffusing agent, the cost of the optical member 570 is low.

[0193] Since the optical member 570 does not contain a diffusing agent, the options for the material of the optical member 570 are broadened, and mass production is stable.

[0194] In the above-described embodiment, the power tool is the driver drill 1. The power tool may be a polisher, a pin cutter, a hammer drill, an impact driver, or an impact wrench.

[0195] 19 is a front perspective view showing a polisher 101 according to an embodiment. The polisher 101 includes a motor 106, a polishing unit 108 (output shaft) disposed forward of the motor 106 and rotated by the motor 106, a motor housing 121 housing the motor 106, a grip unit 122 disposed below the motor housing 121, a battery holding unit 123 disposed below the grip unit 122, and a light unit 14 disposed in the battery holding unit 123. The light unit 14 includes a COB light 50. The battery holding unit 123 holds a battery 20. The COB light 50 can brightly illuminate a work target of the polisher 101, making it easier for an operator to see the work target. [Explanation of symbols]

[0196] 1...Driver drill (power tool), 2...Housing, 2L...Left housing, 2R...Right housing, 2S...Screw, 3...Rear cover, 3S...Screw, 4...Casing, 4A...First casing, 4B...Second casing, 4C...Bracket plate, 4D...Stop plate, 4E...Screw, 4S...Screw, 5S...Screw, 5...Battery mounting section, 6...Motor, 7...Power transmission mechanism, 8...Output section (output shaft), 9...Fan, 10...Trigger lever, 11...Forward / reverse switching lever, 12...Speed ​​switching lever, 13...Mode switching ring, 14...Light unit, 15...Interface panel, 16...Diamond 17...trigger signal generating circuit, 18...controller, 18A...controller board, 18B...power supply circuit, 18C...control circuit, 18D...constant current circuit, 19A...air intake, 19B...air exhaust, 20...battery, 21...motor housing, 22...grip, 23...battery holder, 24...light holder, 25A...operation device, 25B...display device, 26...controller case, 27...panel opening, 28...dial opening, 29...light opening, 30...reduction mechanism, 31...first planetary gear mechanism, 31C...first carrier, 31P...planetary gear, 31R...internal gear, 31S ...pinion gear, 32...second planetary gear mechanism, 32C...second carrier, 32P...planetary gear, 32R...internal gear, 32S...sun gear, 33...third planetary gear mechanism, 33C...third carrier, 33P...planetary gear, 33R...internal gear, 33S...sun gear, 34...speed change ring, 34T...projection, 35...connecting ring, 36...coil spring, 40...vibration mechanism, 41...first cam, 42...second cam, 43...vibration change ring, 43S...opposing portion, 43T...projection, 44...stop ring, 45...support ring, 46...steel ball, 47...washer , 48... cam ring, 49... mode detection ring, 49M... permanent magnet, 50... COB light (chip on board light emitting diode), 51... substrate, 52... LED element (light emitting element), 53... LED circuit, 54... bank, 55... phosphor, 57... optical member, 57A... light transmitting portion, 57B... upper surrounding portion, 57C... lower surrounding portion, 57D... upper convex portion, 57E... lower convex portion, 57F... total reflection surface, 57G... incident surface, 57H... exit surface, 61... stator, 61A... stator core, 61B... front insulator, 61C... rear insulator, 61D... coil, 61E... sensor circuit board,61F...fusing terminal, 61G...short circuit member, 62...rotor, 62A...rotor core, 62B...permanent magnet, 63...rotor shaft, 64...bearing, 65...bearing, 81...spindle, 81F...flange portion, 82...chuck, 83...bearing, 84...bearing, 85...lock cam, 86...lock ring, 87...coil spring, 91...first circuit configuration, 92...second circuit configuration, 101...polisher (power tool), 106...motor, 108...polishing portion (output shaft), 121...motor housing portion, 122...grip portion, 123...battery holding portion, 570...optical member, 570H...emission surface, 570T...convex portion, AX...rotating shaft.

Claims

1. a motor having a stator and a rotor rotatable relative to the stator; an output shaft disposed forward of the motor and rotated by the motor; a motor housing portion that houses the motor; a grip portion disposed below the motor housing portion; a battery holding portion disposed below the grip portion; a COB light disposed in the battery holding portion, Power tools.

2. The COB light is disposed in front of the battery holder. The power tool according to claim 1 .

3. The COB light includes a substrate and an LED element mounted on a front surface of the substrate, The substrate is long in the left-right direction. The power tool according to claim 1 .

4. The LED elements are mounted in plurality at intervals in the left-right direction. The power tool according to claim 3.

5. an optical member disposed forward of the COB light and having a light-transmitting portion through which light emitted from the COB light passes; The power tool according to claim 1 .

6. The optical member is disposed in a light opening provided in the battery holding portion. The power tool according to claim 5.

7. The optical member is made of a polycarbonate resin containing a white diffusing agent. The power tool according to claim 5.

8. The optical member has a light transmittance of 40% or more and 70% or less. The power tool according to claim 5.

9. The optical member has an incident surface on which light from the COB light is incident, a total reflection surface that totally reflects the light from the COB light, and an exit surface that emits the light from the incident surface and the light from the total reflection surface. The power tool according to claim 5.

10. The total reflection surface is disposed above the incident surface. The power tool according to claim 9.

11. the optical member has an upper surrounding portion extending rearward from an upper end of the light transmitting portion, and an upper convex portion protruding upward from the upper surrounding portion, the total reflection surface is disposed on the upper convex portion; The power tool according to claim 10.

12. The optical member has a lower surrounding portion extending rearward from a lower end of the light transmitting portion, and a lower convex portion protruding downward from the lower surrounding portion. The power tool according to claim 5.

13. The COB light includes a substrate and an LED element mounted on a front surface of the substrate, an angle between the rotation axis of the motor and a normal to the front surface of the substrate is equal to or greater than 5 degrees and equal to or less than 20 degrees; The power tool according to claim 1 .

14. The COB light includes a substrate and an LED element mounted on a front surface of the substrate, At least four of the LED elements are mounted at intervals in the left-right direction, a first group of LED elements including a first LED element and a second LED element are connected in series; a second group of LED elements including the third LED element and the fourth LED element are connected in series; The first group of LED elements and the second group of LED elements are connected in parallel, The second group of LED elements is disposed between the first LED elements and the second LED elements in the left-right direction. The power tool according to claim 1 .

15. a third group of LED elements including the fifth LED element and the sixth LED element are connected in series; The first group of LED elements, the second group of LED elements, and the third group of LED elements are connected in parallel, In the left-right direction, the second group of LED elements is disposed between the first LED element and the second LED element, and the third group of LED elements is disposed between the third LED element and the fourth LED element. The power tool of claim 14.

16. The rated voltage of the battery held in the battery holding unit is 25.2 V or more. The power tool according to claim 1 .

17. The rated voltage of the battery held in the battery holding unit is 21.6 V or more, The voltage of the battery is applied to the COB light without being stepped down. The power tool according to claim 1 .

18. a motor having a stator and a rotor rotatable relative to the stator; an output shaft rotated by the rotor; a housing that accommodates the motor; a COB light disposed in the housing; The rated voltage of the battery held in the battery holding portion of the housing is 25.2 V or more. Power tools.

19. a motor having a stator and a rotor rotatable relative to the stator; an output shaft rotated by the rotor; a housing that accommodates the motor; a COB light disposed in the housing; The rated voltage of the battery held in the battery holding portion of the housing is 21.6 V or more, The voltage of the battery is applied to the COB light without being stepped down. Power tools.

20. The COB light includes a substrate and an LED element mounted on the substrate, At least six of the LED elements are mounted, At least six LED elements are connected in series; 20. The power tool of claim 19.

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