Power tools

Abstract

To improve the irradiation state of light emitted from a chip-on-board light-emitting diode.SOLUTION: A power tool includes: a motor; an output shaft rotated by the rotational force of the motor; a chip-on-board light-emitting diode that has a substrate having an annular portion, and an LED chip disposed on a front surface of the annular portion, and is disposed around the output shaft; and a light cover that has an inner cylinder portion disposed on the radially inside with respect to the annular portion, and a light transmission portion through which light emitted from the LED chip passes, and is fixed to the substrate. The inner cylinder portion has a cover slope that totally reflects the light from the LED chip forward.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The technology disclosed herein relates to power tools. [Background technology]

[0002] BACKGROUND ART In the technical field related to power tools, a lighting system for a power tool, such as that disclosed in Patent Document 1, is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2016 / 0354889 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the lighting system for a power tool includes chip-on-board light-emitting diodes (COB LEDs). The chip-on-board LEDs have a high light output and can brightly illuminate a work object. However, there is room for improvement in the illumination state of the light emitted from the chip-on-board LEDs disclosed in Patent Document 1. For example, it is desirable for the chip-on-board LEDs to illuminate the work object with a uniform illuminance distribution or an appropriate illuminance.

[0005] The technology disclosed in this specification aims to improve the illumination state of light emitted from chip-on-board light-emitting diodes. [Means for solving the problem]

[0006] This specification discloses a power tool. The power tool may include a motor, an output shaft that rotates due to the torque of the motor, a substrate having an annular portion, an LED chip disposed on the front surface of the annular portion, chip-on-board light-emitting diodes disposed around the output shaft, an inner cylindrical portion disposed radially inward from the annular portion, and a light cover that has a light-transmitting portion through which light emitted from the LED chip passes and is fixed to the substrate. The inner cylindrical portion may have a cover slope that totally reflects light from the LED chip forward. [Effects of the Invention]

[0007] According to the above configuration, the illumination state of the light emitted from the chip-on-board light-emitting diode is improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front perspective view showing a power tool according to a first embodiment. [Figure 2] FIG. 2 is a side view showing the power tool according to the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view showing the power tool according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing the upper part of the power tool according to the first embodiment. [Figure 5] FIG. 5 is a diagram schematically showing the chip-on-board light-emitting diode according to the first embodiment. [Figure 6] FIG. 6 is a perspective view showing the light unit according to the first embodiment, as viewed from the front. [Figure 7] FIG. 7 is a perspective view showing the light unit according to the first embodiment, seen from behind. [Figure 8] FIG. 8 is an exploded perspective view from the front showing the light unit according to the first embodiment. [Figure 9] FIG. 9 is an exploded perspective view showing the light unit according to the first embodiment, as seen from behind. [Figure 10] FIG. 10 is a rear view of the light cover according to the first embodiment. [Figure 11] FIG. 11 is a view of the upper part of the power tool according to the first embodiment as seen from the front. [Figure 12] FIG. 12 is an exploded perspective view of the upper portion of the power tool according to the first embodiment, as viewed from the front. [Figure 13] FIG. 13 is an exploded perspective view of the upper portion of the power tool according to the first embodiment, seen from the rear. [Figure 14] FIG. 14 is a cross-sectional view showing a part of the power tool according to the first embodiment. [Figure 15] FIG. 15 is a perspective view of a part of a power tool according to a second embodiment, seen from the front. [Figure 16] FIG. 16 is a cross-sectional view showing a part of a power tool according to the second embodiment. [Figure 17] FIG. 17 is a block diagram showing a power tool according to the second embodiment. [Figure 18] FIG. 18 is a diagram showing a plurality of LED chips according to the second embodiment. [Figure 19] FIG. 19 is a diagram showing a first example of a drive circuit for a plurality of LED chips according to the second embodiment. [Figure 20] FIG. 20 is a diagram showing a second example of a drive circuit for a plurality of LED chips according to the second embodiment. [Figure 21] FIG. 21 is a rear view of the light cover according to the third embodiment. [Figure 22] FIG. 22 is a perspective view showing the light cover according to the fourth embodiment, seen from behind. [Figure 23] FIG. 23 is a rear view of the light cover according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] In one or more embodiments, a power tool may include a motor, an output shaft that rotates due to torque of the motor, a substrate having an annular portion, an LED chip disposed on a front surface of the annular portion, a chip-on-board light-emitting diode (LED) disposed around the output shaft, an inner cylindrical portion disposed radially inward from the annular portion, and a light cover that has a light-transmitting portion through which light emitted from the LED chip passes, and is fixed to the substrate. The inner cylindrical portion may have a cover slope that totally reflects light from the LED chip forward.

[0010] In the above configuration, the inner cylindrical portion of the light cover is provided with a cover slope that totally reflects the light from the LED chip forward, thereby reducing loss of light output from the chip-on-board light-emitting diode. Because loss of light is reduced, the chip-on-board light-emitting diode can illuminate the work object with appropriate illuminance. This improves the illumination quality of the light emitted from the chip-on-board light-emitting diode.

[0011] In one or more embodiments, the cover bevel may be angled forward radially inward.

[0012] In the above configuration, the LED chip is positioned radially outward and rearward of the cover slope, and since the cover slope is inclined forward toward the radial inside, the cover slope can totally reflect the light from the LED chip forward.

[0013] In one or more embodiments, the light-transmitting portion may have an incident surface facing the LED chip and an exit surface from which light from the LED chip that is incident on the incident surface is emitted. At least a portion of the light that is incident on the incident surface may pass through the inside of the light cover and reach the cover slope. The light that is totally reflected by the cover slope may be emitted from the exit surface.

[0014] In the above configuration, light from the LED chip passes through the inside of the light cover and strikes the inclined cover surface at a predetermined angle of incidence, and is thereby totally reflected by the inclined cover surface.

[0015] In one or more embodiments, the entrance surface may be angled forward radially inward.

[0016] In the above configuration, at least a part of the light emitted from the LED chip is emitted from the emission surface so as to be diffused radially outward.

[0017] In one or more embodiments, the power tool may include a reduction mechanism that transmits rotational force of the motor to an output shaft and a gear case that houses the reduction mechanism. The gear case may include a rear cylindrical portion that houses the reduction mechanism, a front cylindrical portion that holds a bearing that supports the output shaft, and an annular portion that connects a front end of the rear cylindrical portion to a rear end of the front cylindrical portion. The chip-on-board light-emitting diode may be disposed around the front cylindrical portion. The inner cylindrical portion may be disposed around the front cylindrical portion and fixed to the front cylindrical portion.

[0018] In the above configuration, the chip-on-board light-emitting diode is fixed to the front cylinder portion of the gear case via the light cover.

[0019] In one or more embodiments, the front cylindrical portion may have a protrusion protruding radially outward from an outer circumferential surface of the front cylindrical portion, and the inner cylindrical portion may have a recess in which the protrusion is disposed.

[0020] In the above configuration, the chip-on-board light-emitting diode is fixed to the front cylinder portion of the gear case via the light cover.

[0021] In one or more embodiments, the cover bevel may define at least a portion of the recess.

[0022] In the above configuration, the recess is provided with a cover slope.

[0023] In one or more embodiments, the protrusion may have a case bevel that faces the cover bevel.

[0024] In the above configuration, the connection between the front cylinder portion and the inner cylinder portion is stable.

[0025] In one or more embodiments, a rear slide portion and a front slide portion disposed forward of the rear slide portion may be provided on the inner circumferential surface of the inner cylindrical portion. The rear slide portion and the slide portion may each protrude radially inward from the inner circumferential surface of the inner cylindrical portion. The recess may be provided between the rear slide portion and the front slide portion. The cover slope may be provided on the front slide portion.

[0026] In the above configuration, the recess is defined by the rear slide portion and the front slide portion.

[0027] In one or more embodiments, a plurality of rear slide portions may be provided at intervals in the circumferential direction of the inner cylindrical portion. The front slide portions may be disposed in front of the plurality of rear slide portions. An insertion opening may be provided between one circumferential end of the rear slide portion and the front slide portion. The protrusion may be disposed in the recess via the insertion opening.

[0028] In the above configuration, the protrusion is disposed in the recess through the insertion opening.

[0029] In one or more embodiments, after the convex portion is inserted into the insertion port, the light cover may be rotated so that the convex portion is inserted inside the recessed portion, thereby fixing the light cover and the gear case together.

[0030] In the above configuration, the light cover and the gear case are fixed together by rotating relative to each other.

[0031] In one or more embodiments, the substrate may have an annular portion. The LED chip may be disposed on a front surface of the annular portion. The inner cylindrical portion may be disposed radially inward from the annular portion. The light cover may have an outer cylindrical portion disposed radially outward from the annular portion. The light-transmitting portion may be disposed to connect a front end of the outer cylindrical portion and a front end of the inner cylindrical portion.

[0032] In the above configuration, the outer cylindrical portion of the light cover is positioned radially outside the annular portion, and the inner cylindrical portion of the light cover is positioned radially inside the annular portion, thereby stabilizing the connection between the substrate and the light cover.

[0033] In one or more embodiments, the output shaft may include an anvil. The power tool may include a striking mechanism to which rotational force of the motor is transmitted via a reduction mechanism and which strikes the anvil in a rotational direction. The gear case may be a hammer case that houses the reduction mechanism and the striking mechanism.

[0034] In the above configuration, the chip-on-board light emitting diode is applied to an impact tool.

[0035] In one or more embodiments, the light-transmitting portion may have an incident surface facing the LED chip and an exit surface from which light from the LED chip that has entered through the incident surface exits. At least a portion of the light that has entered the incident surface may pass through the interior of the light cover and reach the cover slope. The light that has been totally reflected by the cover slope may exit from the exit surface. An uneven portion may be formed on the incident surface.

[0036] In the above configuration, the light emitted from the LED chip is diffused at the incident surface due to the unevenness formed on the incident surface. This allows the work object to be illuminated with a uniform illuminance distribution. This improves the illumination quality of the light emitted from the chip-on-board light-emitting diode.

[0037] In one or more embodiments, a power tool may include a motor, an output shaft that rotates due to the torque of the motor, a substrate having an annular portion, an LED chip disposed on a front surface of the annular portion, chip-on-board light-emitting diodes disposed around the output shaft, and a light cover fixed to the substrate and having a light-transmitting portion through which light emitted from the LED chip passes. The light-transmitting portion may have an incident surface facing the LED chip and an exit surface through which light from the LED chip that enters from the incident surface exits. The incident surface may have an uneven portion formed thereon.

[0038] In the above configuration, the light emitted from the LED chip is diffused at the incident surface due to the unevenness formed on the incident surface. This allows the work object to be illuminated with a uniform illuminance distribution. This improves the illumination quality of the light emitted from the chip-on-board light-emitting diode.

[0039] In one or more embodiments, the power tool may include a motor, an output shaft that rotates due to the rotational force of the motor, a chip-on-board light-emitting diode arranged around the output shaft, an illuminance sensor, and an LED control circuit that controls the illumination state of light emitted from the chip-on-board light-emitting diode based on the detection value of the illuminance sensor.

[0040] In the above configuration, the illumination state of the light emitted from the chip-on-board light-emitting diode is controlled by the LED control circuit based on the detection value of the illuminance sensor, so the work object is illuminated with appropriate illuminance, thereby improving the illumination state of the light emitted from the chip-on-board light-emitting diode.

[0041] In one or more embodiments, the illuminance sensor may receive light emitted from the LED chip and reflected by the work object, and the LED control circuit may reduce the amount of light emitted from the LED chip if it determines that the detected value of the illuminance sensor exceeds a predetermined tolerance.

[0042] In the above configuration, the work object is illuminated with appropriate illuminance. When the amount of light output from the chip-on-board light-emitting diode is large, the amount of light reflected from the work object also increases. If the amount of light reflected from the work object is large, the worker may feel dazzled, which may cause discomfort and reduced work efficiency. When the amount of light reflected from the work object is large enough to cause dazzle to the worker, i.e., when the detection value of the illuminance sensor exceeds a predetermined allowable value, the LED control circuit reduces the amount of light emitted from the LED chip. This ensures that the work object is illuminated with appropriate illuminance, preventing the worker from feeling dazzled by the light reflected from the work object. This improves the illumination quality of the light emitted from the chip-on-board light-emitting diode.

[0043] In one or more embodiments, a plurality of LED chips may be provided. The illuminance sensor may receive light emitted from each of the plurality of LED chips and reflected by the work object. The LED control circuit may stop light emission from some of the plurality of LED chips when it determines that the detected value of the illuminance sensor exceeds a predetermined tolerance.

[0044] In the above configuration, if the amount of light reflected from the work object is so great that the worker feels dazzled, i.e., if the detection value of the illuminance sensor exceeds a predetermined tolerance, the LED control circuit may stop light emission from some of the multiple LED chips. This illuminates the work object with an appropriate illuminance and prevents the worker from feeling dazzled by the light reflected from the work object. This improves the illumination quality of the light emitted from the chip-on-board light-emitting diodes.

[0045] In one or more embodiments, the power tool may include a reduction mechanism that transmits rotational force of the motor to the output shaft, a gear case that houses the reduction mechanism, and a trigger lever that is operated to start the motor. The illuminance sensor may be disposed between the gear case and the trigger lever.

[0046] In the above configuration, the illuminance sensor can receive light that is emitted from the chip-on-board light-emitting diode and reflected by the work object.

[0047] In one or more embodiments, the power tool may include a sensor cover disposed in front of the illuminance sensor, and the illuminance sensor may receive light through an opening provided in the sensor cover.

[0048] With the above configuration, ambient light is prevented from entering the illuminance sensor, and the illuminance sensor can properly receive light reflected from the work object.

[0049] Hereinafter, embodiments will be described with reference to the drawings. 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 relative positions or directions based on the center of the power tool.

[0050] [First embodiment] <Power tools> Fig. 1 is a front perspective view of a power tool 1 according to this embodiment. Fig. 2 is a side view of the power tool 1 according to this embodiment. Fig. 3 is a cross-sectional view of the power tool 1 according to this embodiment. Fig. 4 is a cross-sectional view of the upper part of the power tool 1 according to this embodiment.

[0051] In this embodiment, the power tool 1 is an electric tool having an electric motor 6 as a power source. A direction parallel to the rotation axis AX of the motor 6 is referred to as the axial direction, a direction circumferentially around the rotation axis AX is referred to as the circumferential direction or rotation direction, and a radial direction of the rotation axis AX is referred to as the radial direction. In addition, in the radial direction, a position closer to or approaching the rotation axis AX is referred to as the radially inner direction, and a position farther from or away from the rotation axis AX is referred to as the radially outer direction. In this embodiment, the rotation axis AX extends in the front-to-rear direction. One axial side is the front, and the other axial side is the rear.

[0052] In this embodiment, the power tool 1 is an impact tool, which is a type of electric power tool. In the following description, the power tool 1 will be referred to as the impact tool 1 where appropriate.

[0053] In this embodiment, the impact tool 1 is an impact driver, which is a type of screw tightening tool. The impact tool 1 includes a housing 2, a rear cover 3, a hammer case 4, a case cover 5, a motor 6, a reduction mechanism 7, a spindle 8, a striking mechanism 9, an anvil 10, a tool holding mechanism 11, a fan 12, a battery mounting portion 13, a trigger lever 14, a forward / reverse rotation switch lever 15, a hand mode switch button 16, a controller 17, and a light unit 18.

[0054] 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 located to the right of the left housing 2L. The left housing 2L and the right housing 2R are fixed together with a plurality of screws 2S. The housing 2 is made up of a pair of split housing halves.

[0055] The housing 2 has a motor accommodating portion 21, a grip portion 22, and a battery holding portion 23.

[0056] The motor housing portion 21 is cylindrical and houses the motor 6, a part of the bearing box 24, and the rear part of the hammer case 4.

[0057] The grip portion 22 protrudes downward from the motor housing portion 21. The trigger lever 14 is provided on the upper portion of the grip portion 22. The grip portion 22 is held by an operator.

[0058] The battery holding portion 23 is connected to the lower end of the grip portion 22. The outer dimensions of the battery holding portion 23 are larger than the outer dimensions of the grip portion 22 in both the front-rear direction and the left-right direction.

[0059] The rear cover 3 is made of synthetic resin. The rear cover 3 is disposed behind the motor housing portion 21. The rear cover 3 accommodates at least a portion of the fan 12. The fan 12 is disposed on the inner peripheral side of the rear cover 3. The rear cover 3 is disposed so as to cover the opening at the rear end of the motor housing portion 21.

[0060] The motor accommodating section 21 has an air intake port 19. The rear cover 3 has an air exhaust port 20. Air from the external space of the housing 2 flows into the internal space of the housing 2 through the air intake port 19. Air from the internal space of the housing 2 flows out to the external space of the housing 2 through the air exhaust port 20.

[0061] The hammer case 4 functions as a gear case that houses the reduction mechanism 7. The hammer case 4 houses at least a part of the reduction mechanism 7, the spindle 8, the striking mechanism 9, and the anvil 10. The hammer case 4 is made of metal. In this embodiment, the hammer case 4 is made of aluminum. The hammer case 4 is cylindrical.

[0062] The hammer case 4 includes a rear-side tubular portion 4A, a front-side tubular portion 4B, and an annular portion 4C. The front-side tubular portion 4B is disposed forward of the rear-side tubular portion 4A. The outer diameter of the rear-side tubular portion 4A is larger than the outer diameter of the front-side tubular portion 4B. The inner diameter of the rear-side tubular portion 4A is larger than the inner diameter of the front-side tubular portion 4B. The annular portion 4C is disposed to connect the front end of the rear-side tubular portion 4A and the rear end of the front-side tubular portion 4B.

[0063] The hammer case 4 is connected to the front part of the motor accommodating section 21. A bearing box 24 is fixed to the rear part of the rear side cylindrical section 4A. At least a part of the reduction mechanism 7 is arranged inside the bearing box 24. A screw thread is formed on the outer periphery of the bearing box 24. A screw groove is formed on the inner periphery of the rear part of the rear side cylindrical section 4A. The screw thread of the bearing box 24 and the screw groove of the rear side cylindrical section 4A are coupled together, thereby fixing the bearing box 24 and the hammer case 4. The hammer case 4 is sandwiched between the left housing 2L and the right housing 2R. A part of the bearing box 24 and the rear part of the rear side cylindrical section 4A are housed in the motor accommodating section 21. The bearing box 24 is fixed to both the motor accommodating section 21 and the hammer case 4.

[0064] The case cover 5 covers at least a portion of the surface of the hammer case 4. In this embodiment, the case cover 5 covers the surface of the rear side tubular portion 4A. The case cover 5 is made of synthetic resin. In this embodiment, the case cover 5 is made of polycarbonate resin. The case cover 5 protects the hammer case 4. The case cover 5 prevents contact between the hammer case 4 and objects around the impact tool 1. The case cover 5 prevents contact between the hammer case 4 and the worker.

[0065] The motor 6 is a power source of the impact tool 1. The motor 6 generates rotational force. The motor 6 is an electric motor. The motor 6 is an inner rotor type brushless motor. The motor 6 has a stator 26 and a rotor 27. The stator 26 is supported by the motor accommodating portion 21. At least a portion of the rotor 27 is disposed inside the stator 26. The rotor 27 rotates relative to the stator 26. The rotor 27 rotates around a rotation axis AX extending in the front-rear direction.

[0066] The stator 26 includes a stator core 28 , a front insulator 29 , a rear insulator 30 , and a coil 31 .

[0067] The stator core 28 is disposed radially outward of the rotor 27. The stator core 28 includes a plurality of stacked steel plates. The steel plates are metal plates whose main component is iron. The stator core 28 is cylindrical. The stator core 28 has a plurality of teeth that support the coils 31.

[0068] The front insulator 29 is provided in the front portion of the stator core 28. The rear insulator 30 is provided in the rear portion of the stator core 28. The front insulator 29 and the rear insulator 30 are each an electrical insulating member made of synthetic resin. The front insulator 29 is arranged so as to cover part of the surface of the teeth. The rear insulator 30 is arranged so as to cover part of the surface of the teeth.

[0069] The coil 31 is attached to the stator core 28 via the front insulator 29 and the rear insulator 30. Multiple coils 31 are arranged. The coils 31 are arranged around the teeth of the stator core 28 via the front insulator 29 and the rear insulator 30. The coils 31 and the stator core 28 are electrically insulated by the front insulator 29 and the rear insulator 30. The multiple coils 31 are connected via fusing terminals 38.

[0070] The rotor 27 rotates about a rotation axis AX and includes a rotor core portion 32, a rotor shaft portion 33, a rotor magnet , and a sensor magnet .

[0071] The rotor core portion 32 and the rotor shaft portion 33 are each made of steel. In this embodiment, the rotor core portion 32 and the rotor shaft portion 33 are integral. A front portion of the rotor shaft portion 33 protrudes forward from the front end surface of the rotor core portion 32. A rear portion of the rotor shaft portion 33 protrudes rearward from the rear end surface of the rotor core portion 32.

[0072] The rotor magnet 34 is fixed to the rotor core portion 32. The rotor magnet 34 is cylindrical. The rotor magnet 34 is arranged around the rotor core portion 32.

[0073] The sensor magnet 35 is fixed to the rotor core portion 32. The sensor magnet 35 has an annular shape. The sensor magnet 35 is disposed on the front end surface of the rotor core portion 32 and the front end surface of the rotor magnet 34.

[0074] A sensor board 37 is attached to the front insulator 29. The sensor board 37 is fixed to the front insulator 29 with screws 29S. The sensor board 37 has an annular circuit board and a magnetic sensor supported by the circuit board. At least a portion of the sensor board 37 faces the sensor magnet 35. The magnetic sensor detects the position of the sensor magnet 35, thereby detecting the position of the rotor 27 in the rotational direction.

[0075] The rear portion of the rotor shaft portion 33 is rotatably supported by a rotor bearing 39. The front portion of the rotor bearing 39 is rotatably supported by a rotor bearing 40. The rotor bearing 39 is held by the rear cover 3. The rotor bearing 40 is held by the bearing box 24. The front end portion of the rotor shaft portion 33 is disposed in the internal space of the hammer case 4 through the opening of the bearing box 24.

[0076] A pinion gear 41 is formed on the front end of the rotor shaft portion 33. The pinion gear 41 is connected to at least a part of the reduction mechanism 7. The rotor shaft portion 33 is connected to the reduction mechanism 7 via the pinion gear 41.

[0077] The reduction mechanism 7 transmits the rotational force of the motor 6 to the spindle 8 and the anvil 10. The reduction mechanism 7 is housed in the rear cylindrical portion 4A of the hammer case 4. The reduction mechanism 7 has a plurality of gears. The reduction mechanism 7 is disposed forward of the motor 6. The reduction mechanism 7 connects the rotor shaft portion 33 and the spindle 8. The gears of the reduction mechanism 7 are driven by the rotor 27. The reduction mechanism 7 transmits the rotation of the rotor 27 to the spindle 8. The reduction mechanism 7 rotates the spindle 8 at a rotational speed lower than the rotational speed of the rotor shaft portion 33. The reduction mechanism 7 includes a planetary gear mechanism.

[0078] The reduction mechanism 7 has a plurality of planetary gears 42 arranged around a pinion gear 41, and an internal gear 43 arranged around the plurality of planetary gears 42. The pinion gear 41, the planetary gear 42, and the internal gear 43 are housed in the hammer case 4 and the bearing box 24, respectively. Each of the plurality of planetary gears 42 meshes with the pinion gear 41. The planetary gear 42 is rotatably supported on the spindle 8 via a pin 42P. The spindle 8 is rotated by the planetary gear 42. The internal gear 43 has internal teeth that mesh with the planetary gear 42. The internal gear 43 is fixed to the bearing box 24. The internal gear 43 is always non-rotatable relative to the bearing box 24.

[0079] When the rotor shaft portion 33 is rotated by the drive of the motor 6, the pinion gear 41 rotates, and the planetary gear 42 revolves around the pinion gear 41. The planetary gear 42 revolves while meshing with the internal teeth of the internal gear 43. Due to the revolution of the planetary gear 42, the spindle 8 connected to the planetary gear 42 via the pin 42P rotates at a rotational speed lower than the rotational speed of the rotor shaft portion 33.

[0080] The spindle 8 rotates due to the rotational force of the motor 6. The spindle 8 is disposed forward of at least a portion of the motor 6. The spindle 8 is disposed forward of the stator 26. At least a portion of the spindle 8 is disposed forward of the rotor 27. At least a portion of the spindle 8 is disposed forward of the reduction mechanism 7. The spindle 8 is rotated by the rotor 27. The spindle 8 rotates due to the rotational force of the rotor 27 transmitted by the reduction mechanism 7.

[0081] The spindle 8 has a flange portion 8A and a spindle shaft portion 8B that protrudes forward from the flange portion 8A. The planetary gear 42 is rotatably supported on the flange portion 8A via a pin 42P. The rotation axis of the spindle 8 coincides with the rotation axis AX of the motor 6. The spindle 8 rotates around the rotation axis AX.

[0082] The spindle 8 is rotatably supported by a spindle bearing 44. The spindle bearing 44 is held in the bearing box 24. The spindle 8 has a circular ring portion 8C that protrudes rearward from the rear of the flange portion 8A. The spindle bearing 44 is disposed inside the circular ring portion 8C. In this embodiment, the outer ring of the spindle bearing 44 is connected to the circular ring portion 8C, and the inner ring of the spindle bearing 44 is supported by the bearing box 24.

[0083] The striking mechanism 9 is driven by a motor 6. The rotational force of the motor 6 is transmitted to the striking mechanism 9 via a reduction mechanism 7 and a spindle 8. The striking mechanism 9 strikes the anvil 10 in the rotational direction based on the rotational force of the spindle 8 rotated by the motor 6. The striking mechanism 9 has a hammer 47, a ball 48, and a coil spring 49. The striking mechanism 9 including the hammer 47 is housed in a hammer case 4.

[0084] The hammer 47 is disposed forward of the reduction mechanism 7. The hammer 47 is housed in the rear cylindrical portion 4A. The hammer 47 is disposed around the spindle shaft portion 8B. The hammer 47 is held by the spindle shaft portion 8B. The ball 48 is disposed between the spindle shaft portion 8B and the hammer 47. The coil spring 49 is supported by each of the flange portion 8A and the hammer 47.

[0085] The hammer 47 is rotated by the motor 6. The rotational force of the motor 6 is transmitted to the hammer 47 via the reduction mechanism 7 and the spindle 8. The hammer 47 can rotate together with the spindle 8 based on the rotational force of the spindle 8 rotated by the motor 6. The rotation axis of the hammer 47, the rotation axis of the spindle 8, and the rotation axis AX of the motor 6 coincide with each other. The hammer 47 rotates around the rotation axis AX.

[0086] The ball 48 is made of a metal such as steel. The ball 48 is disposed between the spindle shaft portion 8B and the hammer 47. The spindle 8 has a spindle groove 8D in which at least a portion of the ball 48 is disposed. The spindle groove 8D is provided on a portion of the outer circumferential surface of the spindle shaft portion 8B. The hammer 47 has a hammer groove 47A in which at least a portion of the ball 48 is disposed. The hammer groove 47A is provided on a portion of the inner surface of the hammer 47. The ball 48 is disposed between the spindle groove 8D and the hammer groove 47A. The ball 48 can roll inside the spindle groove 8D and inside the hammer groove 47A. The hammer 47 is movable along with the ball 48. The spindle 8 and the hammer 47 can move relative to each other in the axial direction and the rotational direction within a movable range defined by the spindle groove 8D and the hammer groove 47A.

[0087] The coil spring 49 generates an elastic force that moves the hammer 47 forward. The coil spring 49 is disposed between the flange portion 8A and the hammer 47. A ring-shaped recess 47C is provided on the rear surface of the hammer 47. The recess 47C is recessed forward from the rear surface of the hammer 47. A washer 45 is provided inside the recess 47C. The rear end of the coil spring 49 is supported by the flange portion 8A. The front end of the coil spring 49 is disposed inside the recess 47C and supported by the washer 45.

[0088] The anvil 10 is the output shaft of the impact tool 1 that rotates due to the rotational force of the motor 6. At least a portion of the anvil 10 is positioned forward of the hammer 47. The anvil 10 has a tool hole 10A into which a tool bit is inserted. The tool hole 10A is provided at the front end of the anvil 10. The tool bit is attached to the anvil 10. A protrusion 10B is provided at the rear end of the anvil 10. A recess is provided at the front end of the spindle shaft portion 8B. The protrusion 10B is inserted into the recess provided at the front end of the spindle shaft portion 8B.

[0089] The anvil 10 has a rod-shaped anvil shaft portion 10C and an anvil protrusion portion 10D. The tool hole 10A is provided at the front end of the anvil shaft portion 10C. A tool tip is attached to the anvil shaft portion 10C. The anvil protrusion portion 10D is provided at the rear end of the anvil 10. The anvil protrusion portion 10D protrudes radially outward from the rear end of the anvil shaft portion 10C.

[0090] The anvil 10 is rotatably supported by an anvil bearing 46. The rotation axis of the anvil 10, the rotation axis of the hammer 47, the rotation axis of the spindle 8, and the rotation axis AX of the motor 6 are all coincident. The anvil 10 rotates around the rotation axis AX. The anvil bearing 46 is disposed inside the front cylindrical portion 4B. The anvil bearing 46 is held by the front cylindrical portion 4B of the hammer case 4. The anvil bearing 46 supports the anvil shaft portion 10C. In this embodiment, two anvil bearings 46 are disposed in the front-to-rear direction.

[0091] At least a portion of the hammer 47 is capable of contacting the anvil protrusion 10D. A hammer protrusion that protrudes forward is provided at the front of the hammer 47. The hammer protrusion of the hammer 47 and the anvil protrusion 10D are capable of contacting each other. When the motor 6 is driven while the hammer 47 and the anvil protrusion 10D are in contact with each other, the anvil 10 rotates together with the hammer 47 and the spindle 8.

[0092] The anvil 10 is struck in the rotational direction by the hammer 47. For example, during a screw tightening operation, if the load acting on the anvil 10 becomes too high, a situation may arise in which the anvil 10 cannot be rotated by the power generated by the motor 6 alone. When the power generated by the motor 6 alone is no longer sufficient to rotate the anvil 10, the rotation of the anvil 10 and the hammer 47 stops. The spindle 8 and the hammer 47 are movable relative to each other in the axial and circumferential directions via the ball 48. Even after the rotation of the hammer 47 stops, the rotation of the spindle 8 continues by the power generated by the motor 6. When the spindle 8 rotates while the rotation of the hammer 47 is stopped, the ball 48 moves rearward while being guided by the spindle groove 8D and the hammer groove 47A. The hammer 47 receives force from the ball 48 and moves rearward along with the ball 48. In other words, when the rotation of the anvil 10 is stopped, the hammer 47 moves rearward due to the rotation of the spindle 8. As the hammer 47 moves rearward, the contact between the hammer 47 and the anvil protrusion 10D is released.

[0093] The coil spring 49 generates an elastic force that moves the hammer 47 forward. After moving backward, the hammer 47 moves forward due to the elastic force of the coil spring 49. As the hammer 47 moves forward, it receives a rotational force from the ball 48. That is, the hammer 47 moves forward while rotating. As the hammer 47 moves forward while rotating, it comes into contact with the anvil protrusion 10D while rotating. As a result, the anvil protrusion 10D is struck in the rotational direction by the hammer 47. Both the power of the motor 6 and the inertial force of the hammer 47 act on the anvil 10. Therefore, the anvil 10 can rotate around the rotation axis AX with high torque.

[0094] The tool holding mechanism 11 is disposed around the front portion of the anvil 10. The tool holding mechanism 11 holds the tool bit inserted into the tool hole 10A.

[0095] The fan 12 rotates due to the rotational force of the motor 6. The fan 12 is disposed rearward of the stator 26 of the motor 6. The fan 12 generates an airflow for cooling the motor 6. The fan 12 is fixed to at least a portion of the rotor 27. The fan 12 is fixed to the rear of the rotor shaft 33 via a bushing 12A. The fan 12 is disposed between the rotor bearing 39 and the stator 26. The fan 12 rotates due to the rotation of the rotor 27. As the rotor shaft 33 rotates, the fan 12 rotates together with the rotor shaft 33. As the fan 12 rotates, air from the external space of the housing 2 flows into the internal space of the housing 2 through the air intake 19. The air that has flowed into the internal space of the housing 2 circulates through the internal space of the housing 2, thereby cooling the motor 6. As the fan 12 rotates, the air that has circulated through the internal space of the housing 2 flows out into the external space of the housing 2 through the air exhaust 20.

[0096] The battery attachment section 13 is disposed below the battery holding section 23. The battery attachment section 13 is connected to a battery pack 25. The battery pack 25 is attached to the battery attachment section 13. The battery pack 25 is detachable from the battery attachment section 13. The battery pack 25 functions as a power source for the impact tool 1. The battery pack 25 includes a secondary battery. In this embodiment, the battery pack 25 includes a rechargeable lithium-ion battery. When attached to the battery attachment section 13, the battery pack 25 can supply power to the impact tool 1. The motor 6 and the light unit 18 are each driven by the power supplied from the battery pack 25.

[0097] The trigger lever 14 is provided on the grip portion 22. The trigger lever 14 is operated by an operator to start the motor 6. By operating the trigger lever 14, the motor 6 is switched between being driven and being stopped.

[0098] The forward / reverse switching lever 15 is provided on the upper part of the grip portion 22. The forward / reverse switching lever 15 is operated by an operator. By operating the forward / reverse switching lever 15, the rotation direction of the motor 6 is switched from one of the forward direction and the reverse direction to the other. By switching the rotation direction of the motor 6, the rotation direction of the spindle 8 is switched.

[0099] The hand mode switching button 16 is provided on the upper part of the trigger lever 14. The hand mode switching button 16 is operated by an operator. By operating the hand mode switching button 16, the control mode of the motor 6 is switched.

[0100] The controller 17 outputs control signals to control at least the motor 6 and the light unit 18. The controller 17 is housed in the battery holding section 23. The controller 17 switches the control mode of the motor 6 based on the work content of the impact tool 1. The control mode of the motor 6 refers to a control method or control pattern of the motor 6. The controller 17 includes a circuit board on which multiple electronic components are mounted. Examples of electronic components mounted on the circuit board 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), transistors, and resistors.

[0101] <Light unit> The light unit 18 emits illumination light. The light unit 18 illuminates the anvil 10 and the area around the anvil 10 with the illumination light. The light unit 18 illuminates the area in front of the anvil 10 with the illumination light. The light unit 18 also illuminates the tool tip attached to the anvil 10 and the area around the tool tip with the illumination light.

[0102] The light unit 18 is disposed in the front part of the hammer case 4. The light unit 18 is disposed around the front cylinder portion 4B.

[0103] The light unit 18 includes chip on board light emitting diodes (COB LEDs).

[0104] FIG. 5 is a schematic diagram illustrating a chip-on-board light-emitting diode 50 according to this embodiment. The chip-on-board light-emitting diode 50 includes a substrate 51, an LED chip 52, gold wires 53, a bank 54, a phosphor 55, and a pair of electrodes 56. The substrate 51 may be, for example, an aluminum substrate, a glass cloth-based epoxy resin substrate (FR-4 substrate), or a composite substrate epoxy resin substrate (CEM-3 substrate). The LED chip 52 is mounted on the surface of the substrate 51. The gold wires 53 connect the LED chip 52 to the substrate 51. The gold wires 53 connect the multiple LED chips 52 to each other. The bank 54 is provided on the surface of the substrate 51. The bank 54 is disposed around the LED chip 52. The bank 54 defines a compartment in which the phosphor 55 is disposed. The phosphor 55 is disposed inside the bank 54 so as to cover the LED chip 52. The electrode 56 is disposed on the surface of the substrate 51 outside the bank 54. The electrode 56 may be disposed on the back surface of the substrate 51. Of the pair of electrodes 56, one electrode 56 is a positive electrode 56A and the other electrode 56 is a negative electrode 56B. The electrode 56 is connected to the battery pack 25 via the controller 17 and lead wires. Power output from the battery pack 25 is supplied to the electrode 56 via the controller 17 and lead wires. The power supplied to the electrode 56 is supplied to the LED chip 52 via the substrate 51 and gold wires 53. The LED chip 52 emits light based on the power supplied from the battery pack 25. The voltage of the battery pack 25 is stepped down to 5V and applied to the LED chip 52.

[0105] Fig. 6 is a perspective view of the light unit 18 according to this embodiment, seen from the front. Fig. 7 is a perspective view of the light unit 18 according to this embodiment, seen from the rear. Fig. 8 is an exploded perspective view of the light unit 18 according to this embodiment, seen from the front. Fig. 9 is an exploded perspective view of the light unit 18 according to this embodiment, seen from the rear.

[0106] 6, 7, 8, and 9, the light unit 18 includes a chip-on-board light-emitting diode 50 and a light cover 57. The chip-on-board light-emitting diode 50 includes a substrate 51, a plurality of LED chips 52, a bank 54, a phosphor 55, and a pair of electrodes 56.

[0107] The substrate 51 has an annular portion 51A and a support portion 51B that protrudes downward from the bottom of the annular portion 51A.

[0108] The LED chips 52 are disposed on the front surface of the annular portion 51A of the substrate 51. A plurality of the LED chips 52 are disposed at intervals in the circumferential direction of the annular portion 51A. In this embodiment, 12 LED chips 52 are disposed at equal intervals in the circumferential direction of the annular portion 51A.

[0109] The bank 54 is provided on the front surface of the annular portion 51A of the substrate 51. The bank 54 protrudes forward from the front surface of the annular portion 51A. The bank 54 has an annular shape. In this embodiment, the bank 54 is provided in the form of a double annular ring. That is, in this embodiment, the bank 54 includes a first bank 54 and a second bank 54 arranged radially outward from the first bank 54. The first bank 54 is arranged radially inward from the LED chips 52. The second bank 54 is arranged radially outward from the LED chips 52.

[0110] The phosphor 55 is disposed on the front surface of the annular portion 51A of the substrate 51. The phosphor 55 is annular. The phosphor 55 is disposed between the first bank 54 and the second bank 54. The phosphor 55 is disposed so as to cover each of the plurality of LED chips 52.

[0111] The electrodes 56 are arranged on the rear surface of the substrate 51. In this embodiment, the electrodes 56 are arranged on the rear surface of the annular portion 51A. The electrodes 56 are connected to the controller 17 via lead wires 58. One lead wire 58 is connected to each of the pair of electrodes 56. The pair of lead wires 58 are supported on the rear surface of the support portion 51B. Note that the electrodes 56 may be arranged on, for example, the front surface of the support portion 51B. The lead wires 58 may be supported on the front surface of the support portion 51B.

[0112] The current output from the battery pack 25 is supplied to the electrode 56 via the controller 17 and the lead wire 58. The current supplied to the electrode 56 is supplied to the LED chip 52 via the substrate 51 and the gold wire 53 (not shown in FIGS. 6 to 9). The LED chip 52 emits light based on the current supplied from the battery pack 25.

[0113] FIG. 10 is a rear view of the light cover 57 according to this embodiment. The light cover 57 is connected to the chip-on-board light-emitting diodes 50. The light cover 57 is fixed to the substrate 51. The light cover 57 is made of polycarbonate resin. At least a portion of the light cover 57 is disposed forward of the chip-on-board light-emitting diodes 50. The light cover 57 has an outer cylinder portion 57A, an inner cylinder portion 57B, a light-transmitting portion 57C, and a support portion 57D.

[0114] The outer cylinder portion 57A is disposed radially outward of the inner cylinder portion 57B. At least a portion of the chip-on-board light-emitting diode 50 is disposed radially between the outer cylinder portion 57A and the inner cylinder portion 57B. The outer cylinder portion 57A is disposed radially outward of the annular portion 51A of the substrate 51. The inner cylinder portion 57B is disposed radially inward of the annular portion 51A of the substrate 51.

[0115] The light-transmitting portion 57C has an annular shape. The light-transmitting portion 57C is arranged to connect the front end of the outer cylinder portion 57A and the front end of the inner cylinder portion 57B. The light-transmitting portion 57C faces the front surface of the annular portion 51A. The light-transmitting portion 57C faces the LED chip 52. Light emitted from the LED chip 52 passes through the light-transmitting portion 57C and is irradiated toward the front of the light unit 18.

[0116] The light-transmitting portion 57C has an incident surface 57E through which light from the LED chip 52 enters, and an exit surface 57F through which light transmitted through the light-transmitting portion 57C exits. The incident surface 57E faces the LED chip 52. The light from the LED chip 52 that enters the incident surface 57E exits from the exit surface 57F. The incident surface 57E faces substantially backward. The exit surface 57F faces substantially forward.

[0117] Support portion 57D is provided so as to protrude downward from the lower part of outer cylinder portion 57A. Recessed portion 57G is formed inside support portion 57D. Support portion 51B of substrate 51 is disposed in recessed portion 57G. Two notches 57H are formed in support portion 57D. Lead wires 58 are disposed inside notches 57H.

[0118] Fig. 11 is a view of the upper part of the power tool 1 according to this embodiment as seen from the front. Fig. 12 is an exploded perspective view of the upper part of the power tool 1 according to this embodiment as seen from the front. Fig. 13 is an exploded perspective view of the upper part of the power tool 1 according to this embodiment as seen from the rear. Fig. 14 is a cross-sectional view of a part of the power tool 1 according to this embodiment.

[0119] The light unit 18 including the chip-on-board light emitting diodes 50 is disposed around the anvil shaft portion 10C of the anvil 10. The light unit 18 including the chip-on-board light emitting diodes 50 is disposed around the front cylinder portion 4B of the hammer case 4. The inner cylinder portion 57B of the light cover 57 is disposed around the front cylinder portion 4B of the hammer case 4. The inner cylinder portion 57B of the light cover 57 is fixed to the front cylinder portion 4B of the hammer case 4.

[0120] The substrate 51 is fixed to the light cover 57. The substrate 51 is disposed between the outer cylindrical portion 57A and the inner cylindrical portion 57B in the radial direction. As shown in FIGS. 9 and 10 , a support protrusion 57J is provided on the outer peripheral surface of the inner cylindrical portion 57B. The support protrusion 57J protrudes radially outward from the outer peripheral surface of the inner cylindrical portion 57B. A plurality of the support protrusions 57J are provided at intervals in the circumferential direction. As shown in FIG. 10 , in this embodiment, three support protrusions 57J are provided at intervals in the circumferential direction. The inner peripheral surface of the annular portion 51A of the substrate 51 is supported by the support protrusions 57J. The substrate 51 is fixed to the inner cylindrical portion 57B via an adhesive 59. In this embodiment, the rear surface of the substrate 51 and the outer peripheral surface of the inner cylindrical portion 57B are fixed together with the adhesive 59.

[0121] A protrusion 4D is provided on the outer peripheral surface of the front-side tubular portion 4B. The protrusion 4D protrudes radially outward from the outer peripheral surface of the front-side tubular portion 4B. A plurality of the protrusions 4D are provided at intervals in the circumferential direction. In this embodiment, four protrusions 4D are provided at intervals in the circumferential direction. The surface of the protrusion 4D includes a rear surface 4E facing rearward and an inclined surface 4F that slopes radially inward toward the front.

[0122] The light cover 57 is fixed to the front cylindrical portion 4B of the hammer case 4. A rear slide portion 57M and a front slide portion 57N are provided on the inner circumferential surface of the inner cylindrical portion 57B of the light cover 57. The rear slide portion 57M and the front slide portion 57N each protrude radially inward from the inner circumferential surface of the inner cylindrical portion 57B. The front slide portion 57N is disposed forward of the rear slide portion 57M. A plurality of rear slide portions 57M are provided at intervals in the circumferential direction. The front slide portion 57N is disposed forward of each of the plurality of rear slide portions 57M. In this embodiment, as shown in FIG. 10 , four rear slide portions 57M are provided at intervals in the circumferential direction. The front slide portions 57N are disposed forward of each of the four rear slide portions 57M. Recesses 57K are provided between the rear slide portion 57M and the front slide portion 57N. The protrusion 4D is disposed inside the recess 57K. The rear slide portion 57M has a front surface 57P that contacts the rear surface 4E of the protrusion 4D. The front slide portion 57N has a sloped surface 57Q that faces the sloped surface 4F of the protrusion 4D. The front surface 57P defines at least a portion of the recess 57K. The sloped surface 57Q defines at least a portion of the recess 57K.

[0123] An insertion opening is provided between one circumferential end of the rear slide portion 57M and the front slide portion 57N. The protrusion 4D is disposed in the recess 57K through the insertion opening. After the protrusion 4D is inserted into the insertion opening, the light unit 18 is rotated, whereby the protrusion 4D is inserted into the inside of the recess 57K. This fixes the light cover 57 and the front cylinder portion 4B of the hammer case 4. Fixing the light cover 57 and the front cylinder portion 4B of the hammer case 4 fixes the light unit 18 and the hammer case 4.

[0124] Light emitted from LED chip 52 is incident on incident surface 57E via phosphor 55. As shown in Fig. 14, incident surface 57E is inclined forward and radially inward. The light incident on incident surface 57E passes through light-transmitting portion 57C and then exits from exit surface 57F.

[0125] In this embodiment, the inner cylinder portion 57B has a slope 57Q that totally reflects light from the LED chip 52 forward. The inclination angle of the slope 57Q is set in accordance with the relative positions of the LED chip 52 and the slope 57Q so that the light from the LED chip 52 is totally reflected forward. That is, the inclination angle of the slope 57Q is set so that the angle of incidence of light from the LED chip 52 with respect to the slope 57Q satisfies the condition for total reflection. As indicated by arrow FL in FIG. 14 , at least a portion of the light incident on the entrance surface 57E passes through the interior of the light cover 57 and reaches the slope 57Q. The slope 57Q is inclined forward, radially inward. The light that reaches the slope 57Q is totally reflected by the slope 57Q and travels forward. The light totally reflected by the slope 57Q is emitted from the exit surface 57F.

[0126] In this embodiment, the impact tool 1 is provided with a heat dissipation device that dissipates heat from the chip-on-board light-emitting diode 50. The heat dissipation device includes a heat dissipation member to which the heat from the chip-on-board light-emitting diode 50 is transferred. In this embodiment, the heat dissipation member includes the hammer case 4.

[0127] In this embodiment, the heat of the chip-on-board light-emitting diode 50 is transferred to the hammer case 4 via a thermal interface material 60 (TIM). The thermal interface material 60 is disposed between the hammer case 4 and the light unit 18. The thermal interface material 60 contacts both the substrate 51 of the chip-on-board light-emitting diode 50 and the hammer case 4.

[0128] In this embodiment, the thermally conductive material 60 is disposed between the rear surface of the substrate 51 and the front surface of the annular portion 4C. The thermally conductive material 60 contacts both the rear surface of the substrate 51 and the front surface of the annular portion 4C. The thermal conductivity of the thermally conductive material 60 is higher than that of air. The thermal conductivity of the thermally conductive material 60 is higher than that of the substrate 51. The thermal conductivity of the thermally conductive material 60 is higher than that of the light cover 57. The thermally conductive material 60 is electrically insulating.

[0129] The thermally conductive material 60 may be a coating applied to one or both of the substrate 51 and the hammer case 4, or may be in the form of a solid sheet. In this embodiment, the thermally conductive material 60 is a solid sheet-like member. In the following description, the thermally conductive material 60 will be referred to as the thermally conductive sheet 60 as appropriate.

[0130] The thermally conductive sheet 60 is annular. The thermally conductive sheet 60 has an annular portion 60A that contacts the rear surface of the annular portion 51A of the substrate 51, and a protruding portion 60B that contacts the rear surface of the support portion 51B of the substrate 51. The protruding portion 60B protrudes downward from the lower portion of the annular portion 60A.

[0131] When the trigger lever 14 is operated, the motor 6 starts and light is emitted from the LED chip 52 of the chip-on-board light-emitting diode 50. The amount of light output from the chip-on-board light-emitting diode 50 is high, allowing the work object to be brightly illuminated.

[0132] On the other hand, since the chip-on-board light-emitting diode 50 generates a large amount of heat, the temperature of the chip-on-board light-emitting diode 50 may rise excessively. If the temperature of the chip-on-board light-emitting diode 50 exceeds the allowable value, the LED chip 52 may deteriorate, and the life of the chip-on-board light-emitting diode 50 may be shortened. The allowable value for the temperature of the chip-on-board light-emitting diode 50 is, for example, the heat resistance temperature of the LED chip 52.

[0133] The component that generates the most heat in the chip-on-board light-emitting diode 50 is the LED chip 52. The LED chip 52 is disposed in a space surrounded by the substrate 51 and the light cover 57. The heat of the LED chip 52 is unlikely to escape from the space surrounded by the substrate 51 and the light cover 57. In this embodiment, the heat of the LED chip 52 is transferred to the hammer case 4 via the substrate 51 and the thermally conductive sheet 60. The heat of the chip-on-board light-emitting diode 50 transferred to the hammer case 4 is dissipated into the atmospheric space surrounding the hammer case 4. This prevents the chip-on-board light-emitting diode 50 from excessively increasing in temperature.

[0134] The heat dissipation member may include the case cover 5. The thermally conductive sheet 60 contacts both the annular portion 4C of the hammer case 4 and the front end portion of the case cover 5. The heat from the chip-on-board light-emitting diodes 50 transferred to the case cover 5 is dissipated into the atmospheric space surrounding the case cover 5.

[0135] The thermally conductive sheet 60 may be separated from the case cover 5. The heat of the chip-on-board light-emitting diodes 50 transmitted to the hammer case 4 via the thermally conductive sheet 60 is dissipated via the case cover 5 into the atmospheric space around the case cover 5.

[0136] The heat dissipation member may include the light cover 57. The substrate 51 is in contact with at least one of the outer cylinder portion 57A and the inner cylinder portion 57B while being spaced apart from the light-transmitting portion 57C. After the heat of the chip-on-board light-emitting diode 50 is transferred to the light cover 57, it may be dissipated from the light cover 57 to the atmosphere. Alternatively, the heat of the chip-on-board light-emitting diode 50 may be transferred to the light cover 57 via an adhesive 59.

[0137] In this embodiment, the drive voltage of the light unit 18 is 5 V. The luminous flux of the light unit 18 is 80 lumens or more and 200 lumens or less. The luminous flux of the light unit 18 may be 100 lumens or more and 150 lumens or less, or 120 lumens or more and 140 lumens or less.

[0138] <Effects> As described above, in this embodiment, the impact tool 1 may include the motor 6, the anvil 10 that rotates by the rotational force of the motor 6, the substrate 51 having the annular portion 51A, the chip-on-board light-emitting diodes 50 that have the LED chip 52 disposed on the front surface of the annular portion 51A and are disposed around the anvil 10, the inner cylindrical portion 57B that is disposed radially inward of the annular portion 51A, and the light cover 57 that has the light-transmitting portion 57C through which light emitted from the LED chip 52 passes and is fixed to the substrate 51. The inner cylindrical portion 57B may have an inclined surface 57Q that is a cover inclined surface that totally reflects light from the LED chip 52 forward.

[0139] In the above configuration, the inner cylindrical portion 57B of the light cover 57 is provided with the slope 57Q that totally reflects the light from the LED chip 52 forward, thereby reducing loss of the amount of light output from the chip-on-board light-emitting diode 50. Because loss of light is reduced, the chip-on-board light-emitting diode 50 can illuminate the work object with appropriate illuminance. This improves the illumination state of the light emitted from the chip-on-board light-emitting diode 50.

[0140] In this embodiment, the inclined surface 57Q may be inclined forward and radially inward.

[0141] In the above configuration, the LED chip 52 is positioned radially outward and rearward of the inclined surface 57Q, and since the inclined surface 57Q is inclined forward toward the radially inward direction, the inclined surface 57Q can totally reflect the light from the LED chip 52 forward.

[0142] In the present embodiment, the light transmitting portion 57C may have an incident surface 57E facing the LED chip 52 and an exit surface 57F through which light from the LED chip 52 that has entered the incident surface 57E is emitted. At least a portion of the light that has entered the incident surface 57E may pass through the inside of the light cover 57 and reach the inclined surface 57Q. The light that has been totally reflected by the inclined surface 57Q may be emitted from the exit surface 57F.

[0143] In the above configuration, light from the LED chip 52 passes through the inside of the light cover 57 and is incident on the inclined surface 57Q at a predetermined angle of incidence, and is thereby totally reflected by the inclined surface 57Q.

[0144] In this embodiment, the entrance surface 57E may be inclined forward and radially inward.

[0145] In the above configuration, at least a part of the light emitted from the LED chip 52 is emitted from the emission surface 57F so as to be diffused radially outward.

[0146] In this embodiment, the impact tool 1 may include a speed reduction mechanism 7 that transmits the rotational force of the motor 6 to the anvil 10, and a hammer case 4 that houses the speed reduction mechanism 7. The hammer case 4 may include a rear cylinder portion 4A that houses the speed reduction mechanism 7, a front cylinder portion 4B that holds an anvil bearing 46 that supports the anvil 10, and an annular portion 4C that connects the front end portion of the rear cylinder portion 4A to the rear end portion of the front cylinder portion 4B. The chip-on-board light-emitting diode 50 may be disposed around the front cylinder portion 4B. The inner cylinder portion 57B may be disposed around the front cylinder portion 4B and fixed to the front cylinder portion 4B.

[0147] In the above configuration, the chip-on-board light-emitting diode 50 is fixed to the front cylinder portion 4B of the hammer case 4 via the light cover 57.

[0148] In this embodiment, the front cylinder portion 4B may have a protrusion 4D that protrudes radially outward from the outer circumferential surface of the front cylinder portion 4B. The inner cylinder portion 57B may have a recess 57K in which the protrusion 4D is disposed.

[0149] In the above configuration, the chip-on-board light-emitting diode 50 is fixed to the front cylinder portion 4B of the hammer case 4 via the light cover 57.

[0150] In this embodiment, the inclined surface 57Q may define at least a portion of the recess 57K.

[0151] In the above configuration, the recess 57K is provided with the slope 57Q.

[0152] In this embodiment, the protrusion 4D may have a slope 4F that is a case slope facing the slope 57Q.

[0153] In the above configuration, the connection between the front cylindrical portion 4B and the inner cylindrical portion 57B is stable.

[0154] In the present embodiment, a rear slide portion 57M and a front slide portion 57N disposed forward of the rear slide portion 57M may be provided on the inner circumferential surface of the inner cylindrical portion 57B. The rear slide portion 57M and the slide portion may each protrude radially inward from the inner circumferential surface of the inner cylindrical portion 57B. A recess 57K may be provided between the rear slide portion 57M and the front slide portion 57N. A slope 57Q may be provided on the front slide portion 57N.

[0155] In the above configuration, the recess 57K is defined by the rear slide portion 57M and the front slide portion 57N.

[0156] In this embodiment, a plurality of rear slide portions 57M may be provided at intervals in the circumferential direction of the inner cylindrical portion 57B. The front slide portions 57N may be disposed in front of the plurality of rear slide portions 57M. An insertion opening may be provided between one circumferential end of the rear slide portion 57M and the front slide portion 57N. The protrusion 4D may be disposed in the recess 57K via the insertion opening.

[0157] In the above configuration, the protrusion 4D is placed in the recess 57K through the insertion opening.

[0158] In this embodiment, after the protrusion 4D is inserted into the insertion opening, the light cover 57 may be rotated so that the protrusion 4D is inserted into the inside of the recess 57K, and the light cover 57 and the hammer case 4 are fixed together.

[0159] In the above configuration, the light cover 57 and the hammer case 4 are fixed together by rotating the light cover 57 and the hammer case 4 relative to each other.

[0160] In this embodiment, the substrate 51 may have an annular portion 51A. The LED chip 52 may be disposed on the front surface of the annular portion 51A. The inner cylinder portion 57B may be disposed radially inward from the annular portion 51A. The light cover 57 may have an outer cylinder portion 57A disposed radially outward from the annular portion 51A. The light transmitting portion 57C may be disposed to connect the front end of the outer cylinder portion 57A and the front end of the inner cylinder portion 57B.

[0161] In the above configuration, the outer tube portion 57A of the light cover 57 is positioned radially outside the annular portion 51A, and the inner tube portion 57B of the light cover 57 is positioned radially inside the annular portion 51A, thereby stabilizing the connection between the substrate 51 and the light cover 57.

[0162] [Second embodiment] A second embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment will be denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0163] <Power tools> Fig. 15 is a front perspective view showing a part of a power tool 1B according to this embodiment. Fig. 16 is a cross-sectional view showing a part of the power tool 1B according to this embodiment. The power tool 1B is an impact tool 1B.

[0164] As in the above-described embodiment, the impact tool 1B includes a hammer case 4 that houses a speed reduction mechanism 7, a trigger lever 14 that is operated to start the motor 6, and a light unit 18.

[0165] In this embodiment, the impact tool 1B includes an illuminance sensor 70. The illuminance sensor 70 is disposed between the hammer case 4 and the trigger lever 14 in the vertical direction. The illuminance sensor 70 is supported on a circuit board 71.

[0166] A sensor cover 80 is disposed in front of the illuminance sensor 70. The illuminance sensor 70 receives light through an opening 81 provided in the sensor cover 80.

[0167] FIG. 17 is a block diagram showing a power tool 1B according to this embodiment. As shown in FIG. 17, the controller 17 includes an illuminance detection circuit 171 and an LED control circuit 172. The illuminance detection circuit 171 acquires detection data from the illuminance sensor 70 and calculates a detection value from the illuminance sensor 70. In this embodiment, the illuminance sensor 70 receives light emitted from the LED chip 52 and reflected by a work object. The detection value from the illuminance sensor 70 indicates the illuminance of the light reflected by the work object. The LED control circuit 172 controls the illumination state of the light emitted from the chip-on-board light-emitting diode 50 based on the detection value from the illuminance sensor 70 calculated by the illuminance detection circuit 171.

[0168] 18 is a diagram showing a plurality of LED chips 52 according to this embodiment. As in the above-described embodiment, the light unit 18 has 12 LED chips 52 arranged in the circumferential direction. In the following description, the 12 LED chips 52 arranged in the circumferential direction will be referred to as LED chip 52A, LED chip 52B, LED chip 52C, LED chip 52D, LED chip 52E, LED chip 52F, LED chip 52G, LED chip 52H, LED chip 52I, LED chip 52J, LED chip 52K, and LED chip 52L, respectively.

[0169] LED chip 52B is arranged next to one circumferential side of LED chip 52A. LED chip 52C is arranged next to one circumferential side of LED chip 52B. LED chip 52D is arranged next to one circumferential side of LED chip 52C. LED chip 52E is arranged next to one circumferential side of LED chip 52D. LED chip 52F is arranged next to one circumferential side of LED chip 52E. LED chip 52G is arranged next to one circumferential side of LED chip 52F. LED chip 52H is arranged next to one circumferential side of LED chip 52G. LED chip 52I is arranged next to one circumferential side of LED chip 52H. LED chip 52J is arranged next to one circumferential side of LED chip 52I. LED chip 52K is arranged next to one circumferential side of LED chip 52J. LED chip 52L is arranged next to one circumferential side of LED chip 52K. LED chip 52A is arranged next to one circumferential side of LED chip 52L.

[0170] Fig. 19 is a diagram showing a first example of a drive circuit for a plurality of LED chips 52 according to this embodiment. As shown in Fig. 19, 12 LED chips 52 (52A to 52L) are connected in parallel with each other. An LED driver 173 is connected to the 12 LED chips 52. The 12 LED chips 52 are driven by the LED driver 173. The LED driver 173 is controlled by an LED control circuit 172 of the controller 17. Each of the 12 LED chips 52 is connected to ground via a resistor.

[0171] 19, when the LED control circuit 172 of the controller 17 determines that the detection value of the illuminance sensor 70 exceeds a predetermined allowable value, it reduces the amount of light emitted from the LED chips 52. That is, when the LED control circuit 172 of the controller 17 determines that the detection value of the illuminance sensor 70 exceeds the allowable value while all of the 12 LED chips 52 are lit at a first light amount, it causes all of the 12 LED chips 52 to be lit at a second light amount that is lower than the first light amount.

[0172] In addition, if the LED control circuit 172 of the controller 17 determines that the detection value of the illuminance sensor 70 exceeds a predetermined allowable value, it may stop the light emission of some of the 12 LED chips 52.

[0173] FIG. 20 is a diagram showing a second example of a drive circuit for a plurality of LED chips 52 according to this embodiment. As shown in FIG. 20, a first group of six LED chips 52 consisting of LED chips 52A, 52C, 52E, 52G, 52I, and 52K are connected in parallel to one another, and a second group of six LED chips 52 consisting of LED chips 52B, 52D, 52F, 52H, 52J, and 52L are connected in parallel to one another. A first LED driver 173A is connected to the six LED chips 52 in the first group, and a second LED driver 173B is connected to the six LED chips 52 in the second group. The six LED chips 52 in the first group are driven by the first LED driver 173A, and the six LED chips 52 in the second group are driven by the second LED driver 173B. The first LED driver 173A and the second LED driver 173B are each controlled by the controller 17. Each of the 12 LED chips 52 is connected to ground via a resistor.

[0174] 20, when the LED control circuit 172 of the controller 17 determines that the detection value of the illuminance sensor 70 exceeds the allowable value while all 12 LED chips 52 are turned on, it continues to turn on the six LED chips 52 in the first group and turns off the six LED chips 52 in the second group. The LED chips 52 to be turned on and the LED chips 52 to be turned off are arranged alternately one by one in the circumferential direction.

[0175] Note that when it is determined that the detection value of the illuminance sensor 70 exceeds the allowable value, the number and positions of the LED chips 52 to be turned on and the number and positions of the LED chips 52 to be turned off can be set arbitrarily. For example, when it is determined that the detection value of the illuminance sensor 70 exceeds the allowable value in a state where 12 LED chips 52 are turned on, the LED control circuit 172 of the controller 17 may continue to turn on 8 LED chips 52 and turn off the remaining 4 LED chips 52. The LED chips 52 to be turned on and the LED chips 52 to be turned off may be arranged alternately in the circumferential direction.

[0176] <Effects> As described above, in this embodiment, the impact tool 1B may include a chip-on-board light-emitting diode 50 arranged around the anvil 10, an illuminance sensor 70, and a controller 17 having an LED control circuit 172 that controls the irradiation state of light emitted from the chip-on-board light-emitting diode 50 based on the detection value of the illuminance sensor 70.

[0177] In the above configuration, the illumination state of the light emitted from the chip-on-board light-emitting diodes 50 is controlled by the LED control circuit 172 of the controller 17 based on the detection value of the illuminance sensor 70, so the work object is illuminated with appropriate illuminance. Therefore, the illumination state of the light emitted from the chip-on-board light-emitting diodes 50 is improved.

[0178] In this embodiment, the illuminance sensor 70 may receive light emitted from the LED chip 52 and reflected by the work object. The LED control circuit 172 of the controller 17 may reduce the amount of light emitted from the LED chip 52 when it determines that the detected value of the illuminance sensor 70 exceeds a predetermined allowable value.

[0179] In the above configuration, the work object is illuminated with appropriate illuminance. When the amount of light output from the chip-on-board light-emitting diodes 50 is large, the amount of light reflected by the work object also increases. If the amount of light reflected by the work object is large, the worker may feel dazzled, which may cause discomfort and reduced work efficiency. If the amount of light reflected by the work object is large enough to cause dazzle to the worker, i.e., if the detection value of the illuminance sensor 70 exceeds a predetermined allowable value, the LED control circuit 172 of the controller 17 reduces the amount of light emitted from the LED chip 52. This ensures that the work object is illuminated with appropriate illuminance, preventing the worker from feeling dazzled by the light reflected by the work object. This improves the illumination quality of the light emitted from the chip-on-board light-emitting diodes 50.

[0180] In this embodiment, a plurality of LED chips 52 may be provided. The illuminance sensor 70 may receive light emitted from each of the plurality of LED chips 52 and reflected by the work object. The LED control circuit 172 of the controller 17 may stop light emission from some of the plurality of LED chips 52 when it determines that the detection value of the illuminance sensor 70 exceeds a predetermined allowable value.

[0181] In the above configuration, if the amount of light reflected from the work object is so great that the worker feels dazzled, i.e., if the detection value of the illuminance sensor 70 exceeds a predetermined tolerance, the LED control circuit 172 of the controller 17 may stop light emission from some of the multiple LED chips 52. This illuminates the work object with appropriate illuminance, preventing the worker from feeling dazzled by the light reflected from the work object. This improves the illumination state of the light emitted from the chip-on-board light-emitting diodes 50.

[0182] In this embodiment, the impact tool 1 may include a speed reduction mechanism 7 that transmits the rotational force of the motor 6 to the anvil 10, a hammer case 4 that houses the speed reduction mechanism 7, and a trigger lever 14 that is operated to start the motor 6. The illuminance sensor 70 may be disposed between the hammer case 4 and the trigger lever 14.

[0183] In the above configuration, the illuminance sensor 70 can receive light that is emitted from the chip-on-board light-emitting diode 50 and reflected by the work object.

[0184] In this embodiment, the impact tool 1 may include a sensor cover 80 that is disposed in front of the illuminance sensor 70. The illuminance sensor 70 may receive light through an opening 81 provided in the sensor cover 80.

[0185] The above configuration suppresses ambient light from entering the illuminance sensor 70. The illuminance sensor 70 can properly receive light reflected from the work object.

[0186] [Third embodiment] A third embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of these components will be simplified or omitted.

[0187] <Light cover> Fig. 21 is a view of the light cover 157 according to this embodiment as seen from behind. As shown in Fig. 21, minute uneven portions may be formed on the incident surface 157E of the light cover 157. A plurality of uneven portions are formed uniformly on the incident surface 157E. In this embodiment, the incident surface 157E is textured to form the minute uneven portions on the incident surface 157E.

[0188] <Effects> As described above, in this embodiment, the light transmitting portion 157C may have the incident surface 157E facing the LED chip 52. The incident surface 157E may have an uneven portion formed thereon.

[0189] In the above configuration, since the incident surface 157E has an uneven portion, the light emitted from the LED chip 52 is diffused by the incident surface 157E. This allows the work object to be illuminated with a uniform illuminance distribution. Therefore, the illumination state of the light emitted from the chip-on-board light-emitting diode 50 is improved.

[0190] [Fourth embodiment] A fourth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description of these components will be simplified or omitted.

[0191] <Light cover> Fig. 22 is a perspective view from the rear of the light cover 257 according to this embodiment. Fig. 23 is a view of the light cover 257 according to this embodiment as seen from the rear. As shown in Figs. 22 and 23, the light cover 257 has a light-transmitting portion 257C. The light-transmitting portion 257C has an incident surface 257E facing the LED chip 52.

[0192] The incident surface 257E includes a first inclined surface 91 that slopes forward toward one circumferential side, and a second inclined surface 92 that slopes backward toward one circumferential side. A plurality of first inclined surfaces 91 are arranged in the circumferential direction. A plurality of second inclined surfaces 92 are arranged in the circumferential direction. In this embodiment, 12 first inclined surfaces 91 are arranged in the circumferential direction. 12 second inclined surfaces 92 are arranged in the circumferential direction. The first inclined surfaces 91 and the second inclined surfaces 92 are arranged alternately one by one in the circumferential direction. An end portion of the first inclined surface 91 on one circumferential side and an end portion of the second inclined surface 92 on the other circumferential side are connected. An end portion of the second inclined surface 92 on one circumferential side and an end portion of the first inclined surface 91 on the other circumferential side are connected.

[0193] A recess 93 is formed by an end portion on one circumferential side of the first inclined surface 91 and an end portion on the other circumferential side of the second inclined surface 92. A protrusion 94 is formed by an end portion on one circumferential side of the second inclined surface 92 and an end portion on the other circumferential side of the first inclined surface 91. The recess 93 is formed to extend in the radial direction. The protrusion 94 is formed to extend in the radial direction. The recess 93 is formed to be recessed toward the front. The protrusion 94 is formed to protrude toward the rear. A plurality of recesses 93 are arranged in the circumferential direction. A plurality of protrusions 94 are arranged in the circumferential direction. In this embodiment, twelve recesses 93 are arranged in the circumferential direction. Twelve protrusions 94 are arranged in the circumferential direction. The recesses 93 and the protrusions 94 are arranged alternately one by one in the circumferential direction. The LED chips 52 are arranged to face the recesses 93. One LED chip 52 faces one recess 93.

[0194] <Effects> As described above, in this embodiment, the light transmitting portion 257C may have the incident surface 257E facing the LED chip 52. The recessed portion 93 and the protruding portion 94 may be formed on the incident surface 257E.

[0195] In the above configuration, the recesses 93 and the protrusions 94 are formed on the incident surface 257E, so that the light emitted from the LED chip 52 is diffused by the incident surface 257E. In this embodiment, the light emitted from one LED chip 52 is incident on each of the first inclined surface 91 and the second inclined surface 92 that form one recess 93, and then emitted forward from the light cover 257. This allows the work object to be illuminated with a uniform illuminance distribution. This improves the illumination state of the light emitted from the chip-on-board light-emitting diodes 50.

[0196] [Other embodiments] In the first, second and third embodiments described above, the impact tool (1, etc.) is an impact driver. The impact tool (1, etc.) may be an impact wrench.

[0197] In the above-described embodiment, the power source for the power tool (1, etc.) does not have to be a battery pack (25, etc.) and may be a commercial power source (AC power source).

[0198] In the above-described embodiment, the power tool (1, etc.) is an electric tool powered by an electric motor. The power tool may also be a pneumatic tool powered by an air motor. The power source of the power tool is not limited to an electric motor or an air motor, and may be another power source. The power source of the power tool may be, for example, a hydraulic motor or a motor driven by an engine. [Explanation of symbols]

[0199] 1...Power tool (impact tool), 1B...Power tool (impact tool), 2...Housing, 2L...Left housing, 2R...Right housing, 2S...Screw, 3...Rear cover, 4...Hammer case, 4A...Rear cylinder portion, 4B...Front cylinder portion, 4C...Annular portion, 4D...Convex portion, 4E...Rear surface, 4F...Sloped surface (case slope), 5...Case cover, 6...Motor, 7...Reduction mechanism, 8...Spindle, 8A...Flange portion, 8B...Spindle shaft portion, 8C...Annular portion, 8D...Spindle groove, 9...Striking mechanism, 10...Anvil (output shaft), 10A...Tool hole, 10B...Convex portion, 10C...Anvil shaft 10D...anvil protrusion, 11...tool holding mechanism, 12...fan, 12A...bush, 13...battery mounting section, 14...trigger lever, 15...forward / reverse switching lever, 16...handheld mode switching button, 17...controller, 18...light unit, 19...air intake, 20...exhaust port, 21...motor housing section, 22...grip section, 23...battery holding section, 24...bearing box, 25...battery pack, 26...stator, 27...rotor, 28...stator core, 29...front insulator, 29S...screw, 30...rear insulator, 31...coil, 32...rotor core section , 33...rotor shaft portion, 34...rotor magnet, 35...sensor magnet, 37...sensor board, 38...fusing terminal, 39...rotor bearing, 40...rotor bearing, 41...pinion gear, 42...planetary gear, 42P...pin, 43...internal gear, 44...spindle bearing, 45...washer, 46...anvil bearing, 47...hammer, 47A...hammer groove, 47C...recess, 48...ball, 49...coil spring, 50...chip-on-board light-emitting diode, 51...board, 51A...annular portion, 51B...support portion, 52...LED chip, 53...gold wire ya, 54...bank, 55...phosphor, 56...electrode, 56A...positive electrode, 56B...negative electrode, 57...light cover, 57A...outer cylinder portion, 57B...inner cylinder portion, 57C...light transmitting portion, 57D...support portion, 57E...incident surface, 57F...exiting surface, 57G...recess, 57H...notch, 57J...support convex portion, 57K...recess, 57M...rear sliding portion, 57N...front sliding portion, 57P...front surface, 57Q...inclined surface (cover inclined surface), 58...lead wire, 59...adhesive, 60...thermal conductive material (thermal conductive sheet), 60A...annular portion, 60B...convex portion, 70...illuminance sensor, 71...circuit board, 80...sensor cover, 81...opening,91...first inclined surface, 92...second inclined surface, 93...concave portion, 94...convex portion, 57...light cover, 157C...light transmitting portion, 157E...incident surface, 257...light cover, 257C...light transmitting portion, 257E...incident surface, 171...illuminance detection circuit, 172...LED control circuit, 173...LED driver, 173A...LED driver, 173B...LED driver, AX...rotation axis.

Claims

1. A motor; an output shaft that rotates due to the torque of the motor; a chip-on-board light emitting diode (LED) disposed around the output shaft, the chip-on-board LED having a substrate with a circular ring portion and an LED chip disposed on a front surface of the circular ring portion; a light cover fixed to the substrate, the light cover having an inner cylindrical portion disposed radially inward of the annular portion and a light transmitting portion through which light emitted from the LED chip passes; The inner cylinder portion has a cover slope that totally reflects light from the LED chip forward. Power tools.

2. The cover slope is inclined forward toward the inside in the radial direction.

2. The power tool of claim 1.

3. the light transmitting portion has an incident surface facing the LED chip and an exit surface through which light from the LED chip that has entered the incident surface is exited, At least a part of the light incident on the incident surface passes through the inside of the light cover and reaches the cover slope, The light totally reflected by the cover slope is emitted from the emission surface.

2. The power tool of claim 1.

4. The entrance surface is inclined forward toward the inside in the radial direction.

4. The power tool of claim 3.

5. a reduction mechanism that transmits the rotational force of the motor to the output shaft; a gear case that houses the reduction mechanism, the gear case includes a rear-side cylindrical portion that houses the reduction mechanism, a front-side cylindrical portion that holds a bearing that supports the output shaft, and an annular portion that connects a front end portion of the rear-side cylindrical portion and a rear end portion of the front-side cylindrical portion, the chip-on-board light-emitting diodes are disposed around the front barrel portion; the inner cylindrical portion is disposed around the front cylindrical portion and fixed to the front cylindrical portion; 2. The power tool of claim 1.

6. the front-side cylindrical portion has a protrusion protruding radially outward from an outer circumferential surface of the front-side cylindrical portion, The inner cylindrical portion has a recess in which the protrusion is disposed.

6. The power tool of claim 5.

7. The cover bevel defines at least a portion of the recess.

7. The power tool of claim 6.

8. The protrusion has a case slope facing the cover slope.

8. The power tool of claim 7.

9. a rear slide portion and a front slide portion disposed forward of the rear slide portion are provided on an inner peripheral surface of the inner cylindrical portion, the rear slide portion and the front slide portion each protrude radially inward from an inner circumferential surface of the inner cylindrical portion, The recess is provided between the rear slide portion and the front slide portion, The cover slope is provided on the front slide portion.

7. The power tool of claim 6.

10. The rear slide portion is provided in plurality at intervals in the circumferential direction of the inner cylindrical portion, the front slide portion is disposed in front of each of the plurality of rear slide portions, an insertion opening is provided between one circumferential end of the rear slide portion and the front slide portion; The protrusion is disposed in the recess through the insertion opening.

10. The power tool of claim 9.

11. After the protrusion is inserted into the insertion port, the light cover is rotated so that the protrusion is inserted into the inside of the recess, and the light cover and the gear case are fixed together.

11. The power tool of claim 10.

12. the substrate has an annular portion, the LED chip is disposed on the front surface of the annular portion; the inner cylindrical portion is disposed radially inward of the annular portion, the light cover has an outer cylindrical portion disposed radially outward of the annular portion, the light transmitting portion is disposed so as to connect a front end portion of the outer cylindrical portion and a front end portion of the inner cylindrical portion.

6. The power tool of claim 5.

13. the output shaft includes an anvil; a striking mechanism to which the rotational force of the motor is transmitted via the reduction mechanism and which strikes the anvil in the rotational direction; The gear case is a hammer case that accommodates the reduction mechanism and the impact mechanism.

6. The power tool of claim 5.

14. the light transmitting portion has an incident surface facing the LED chip and an exit surface through which light from the LED chip that has entered through the incident surface is exited, At least a part of the light incident on the incident surface passes through the inside of the light cover and reaches the cover slope, The light totally reflected by the cover slope is emitted from the emission surface, A concave-convex portion is formed on the incident surface.

4. The power tool of claim 3.

Images