Impact tools

Abstract

To suppress deterioration in workability using an impact tool.SOLUTION: An impact tool includes a brushless motor, a spindle rotated by the brushless motor, a hammer held by the spindle, an anvil struck in a rotation direction by the hammer, a resin motor housing storing the brushless motor, a hammer case which is connected to the motor housing and stores the hammer and the spindle, a battery holding part which is connected to the motor housing and is mounted with a battery pack having a rated voltage of 18 V, and a light unit which is held by the hammer case and has a plurality of light-emitting elements. A distance between a front end of the anvil and a rear end of the motor housing is 100 mm or less, and maximum fastening torque of the anvil is 210 Nm or more.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] BACKGROUND ART In the technical field related to impact tools, an impact driver equipped with a light, such as that disclosed in Patent Document 1, is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5900141 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed in this specification aims to suppress a decrease in workability when using an impact tool. [Means for solving the problem]

[0005] This specification discloses an impact tool. The impact tool may include a brushless motor, a spindle rotated by the brushless motor, a hammer held by the spindle, an anvil struck in the rotational direction by the hammer, a resin motor housing that houses the brushless motor, a hammer case connected to the motor housing and that houses the hammer and spindle, and a battery holder connected to the motor housing and to which a battery pack with a rated voltage of 18 V is attached. The impact tool may also include a light unit held by the hammer case and having multiple light-emitting elements. The distance from the front end of the anvil to the rear end of the motor housing may be 100 mm or less. The maximum tightening torque of the anvil may be 210 Nm or more. [Effects of the Invention]

[0006] According to the technology disclosed in this specification, the deterioration of workability when using an impact tool is suppressed. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a side view showing an impact tool according to an embodiment. [Figure 2] FIG. 2 is a front view showing the impact tool according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view showing an impact tool according to the embodiment. [Figure 4] FIG. 4 is an exploded perspective view from the front showing the light unit according to the embodiment. [Figure 5] FIG. 5 is a diagram showing the specifications of an impact tool according to a known technique. [Figure 6] FIG. 6 is a graph showing the relationship between the maximum tightening torque of the anvil and the number of light emitting elements according to the prior art and the embodiment. [Figure 7] FIG. 7 is a graph showing the relationship between the overall length of the impact tool according to the prior art and the embodiment and the number of light-emitting elements. [Figure 8] FIG. 8 is a diagram schematically showing a modified example of the light board according to the embodiment. [Figure 9] FIG. 9 is a diagram schematically showing a modified example of the light board according to the embodiment. [Figure 10] FIG. 10 is a diagram schematically illustrating a modified example of the light board according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] In one or more embodiments, the impact tool may include a brushless motor, a spindle rotated by the brushless motor, a hammer held by the spindle, an anvil struck in the rotational direction by the hammer, a resin motor housing that houses the brushless motor, a hammer case connected to the motor housing and that houses the hammer and the spindle, and a battery holder connected to the motor housing and to which a battery pack with a rated voltage of 18 V is attached. The impact tool may also include a light unit held by the hammer case and having a plurality of light-emitting elements. The distance from the front end of the anvil to the rear end of the motor housing may be 100 mm or less. The maximum tightening torque of the anvil may be 210 Nm or more.

[0009] In the above configuration, the light unit has multiple light-emitting elements, so the work environment is brightly illuminated with illumination light. Furthermore, the overall length, which indicates the distance from the front end of the anvil to the rear end of the motor housing, is 100 mm or less, and the maximum tightening torque of the anvil is 210 Nm or more. This prevents a decrease in workability when using an impact tool.

[0010] In one or more embodiments, at least three light emitting elements may be provided.

[0011] In the above configuration, the light unit has at least three light-emitting elements, so the working environment is brightly illuminated with illumination light, thereby preventing a decrease in workability when using an impact tool.

[0012] In one or more embodiments, the impact tool may weigh 1.5 kg or less.

[0013] In the above configuration, the weight of the impact tool with the battery pack attached is 1.5 kg or less, so that the deterioration of workability when using the impact tool is suppressed.

[0014] In one or more embodiments, the maximum rotational speed of the anvil may be 3,000 rpm or less.

[0015] In the above configuration, the maximum rotation speed of the anvil is 3,000 rpm or less, so that the deterioration of workability when using an impact tool is suppressed.

[0016] In one or more embodiments, the impact tool may include a brushless motor, a spindle rotated by the brushless motor, a hammer held by the spindle, an anvil struck in the rotational direction by the hammer, a resin motor housing that houses the brushless motor, a hammer case connected to the motor housing and that houses the hammer and the spindle, and a battery holder connected to the motor housing and to which a battery pack with a rated voltage of 36 V is attached. The impact tool may also include a light unit held by the hammer case and having a plurality of light-emitting elements. The distance from the front end of the anvil to the rear end of the motor housing may be 110 mm or less. The maximum tightening torque of the anvil may be 200 Nm or more.

[0017] In the above configuration, the light unit has multiple light-emitting elements, so the work environment is brightly illuminated with illumination light. Furthermore, the overall length, which indicates the distance from the front end of the anvil to the rear end of the motor housing, is 110 mm or less, and the maximum tightening torque of the anvil is 200 Nm or more. This prevents a decrease in workability when using an impact tool.

[0018] In one or more embodiments, the light unit may include a light substrate disposed at least partially around the hammer case and supporting a plurality of light-emitting elements, and an optical element disposed in front of the light-emitting elements and the light substrate.

[0019] In the above configuration, the light emitting element and the light board are protected by the optical member.

[0020] In one or more embodiments, the impact tool may include a brushless motor, a spindle rotated by the brushless motor, a hammer held by the spindle, an anvil struck in the rotational direction by the hammer, a resin motor housing that houses the brushless motor, a hammer case connected to the motor housing and that houses the hammer and the spindle, and a battery holder connected to the motor housing and to which a battery pack with a rated voltage of 18 V is attached. The impact tool may also include a light unit held by the hammer case and having four light-emitting elements. The maximum tightening torque of the anvil may be 180 Nm or more.

[0021] In the above configuration, the light unit has four light-emitting elements, so the work environment is brightly illuminated with illumination light. Furthermore, the maximum tightening torque of the anvil is 180 Nm or more. Therefore, the deterioration of workability when using an impact tool is suppressed.

[0022] Hereinafter, an embodiment will be described with reference to the drawings. In the embodiment, 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 impact tool 1. The impact tool 1 has a motor 6 as a power source.

[0023] In the embodiment, the direction parallel to the rotation axis AX of the motor 6 is referred to as the axial direction, the direction circumferentially around the rotation axis AX is referred to as the circumferential direction or rotation direction, and the radial direction of the rotation axis AX is referred to as the radial direction.

[0024] 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. In addition, in the radial direction, a position closer to or approaching the rotation axis AX will be referred to as the radially inner side, and a position farther from or away from the rotation axis AX will be referred to as the radially outer side.

[0025] [Impact tools] Fig. 1 is a side view showing an impact tool 1 according to an embodiment. Fig. 2 is a front view showing the impact tool 1 according to an embodiment. Fig. 3 is a cross-sectional view showing the impact tool 1 according to an embodiment. In the embodiment, the impact tool 1 is an impact driver.

[0026] The impact tool 1 includes a housing 2, a rear cover 3, a hammer case 4, a hammer case cover 5, a motor 6, a reduction mechanism 7, a spindle 8, a striking mechanism 9, an anvil 10, a chuck mechanism 11, a fan 12, a battery mounting section 13, a trigger switch 14, a forward / reverse rotation switching lever 15, a mode switching switch 16, a controller 17, and a light unit 18.

[0027] The housing 2 accommodates at least the motor 6. The housing 2 is made of synthetic resin. The housing 2 is a resin housing. The housing 2 is composed of a pair of split housing halves. 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.

[0028] The housing 2 has a motor accommodating portion 21, a grip portion 22, and a battery holding portion 23.

[0029] The motor accommodating portion 21 accommodates the motor 6. The motor accommodating portion 21 is disposed around the motor 6. The motor accommodating portion 21 is cylindrical.

[0030] The grip portion 22 is held by an operator and protrudes downward from the motor housing portion 21. The trigger switch 14 is provided on the upper portion of the grip portion 22.

[0031] The battery holding portion 23 holds the battery pack 25 via the battery attachment portion 13. The battery holding portion 23 houses the controller 17. The battery holding portion 23 is connected to the lower end of the grip portion 22. The external dimensions of the battery holding portion 23 are larger than the external dimensions of the grip portion 22 in both the front-rear and left-right directions.

[0032] The rear cover 3 is fixed to the rear end of the motor housing portion 21. The rear cover 3 is made of synthetic resin. The rear cover 3 is disposed so as to cover the opening at the rear end of the motor housing portion.

[0033] In this embodiment, the motor accommodating portion 21 and the rear cover 3 form a motor housing 200 made of resin that accommodates the motor 6.

[0034] The hammer case 4 houses at least a portion of the reduction mechanism 7, the spindle 8, the striking mechanism 9, and the anvil 10. The hammer case 4 is made of metal. The hammer case 4 is cylindrical. The hammer case 4 is connected to the front of the motor accommodating section 21. The hammer case 4 is sandwiched between the left housing 2L and the right housing 2R. A bearing box 24 is fixed to the rear of the hammer case 4. The bearing box 24 is fixed to both the motor accommodating section 21 and the hammer case 4.

[0035] The hammer case cover 5 covers at least a portion of the surface of the hammer case 4. The hammer case cover 5 is made of synthetic resin. The hammer case cover 5 protects the hammer case 4. The hammer case cover 5 prevents contact between the hammer case 4 and objects around the impact tool 1. The hammer case cover 5 prevents contact between the hammer case 4 and an operator.

[0036] The motor 6 is a power source of the impact tool 1. The motor 6 is an inner rotor type brushless motor. The motor 6 is accommodated in a motor accommodating portion 21 that is a part of the housing 2.

[0037] The motor 6 has a stator 26 and a rotor 27. The stator 26 is supported by the motor housing 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 about a rotation axis AX extending in the front-rear direction.

[0038] The stator 26 includes a stator core 28 , a front insulator 29 , a rear insulator 30 , and a coil 31 .

[0039] 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.

[0040] 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.

[0041] The coil 31 is attached to the stator core 28 via the front insulator 29 and the rear insulator 30. A plurality of 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 plurality of coils 31 are connected via bus bars.

[0042] The rotor 27 rotates about a rotation axis AX and includes a rotor core 32, a rotor shaft 33, a rotor magnet 34, and a sensor magnet 35.

[0043] The rotor core 32 and the rotor shaft 33 are both made of steel. The front portion of the rotor shaft 33 protrudes forward from the front end surface of the rotor core 32. The rear portion of the rotor shaft 33 protrudes rearward from the rear end surface of the rotor core 32. The front and rear portions of the rotor shaft 33 are each rotatably supported by rotor bearings 39. The front rotor bearing 39 is held in the bearing box 24. The rear rotor bearing 39 is held in the rear cover 3. The front end of the rotor shaft 33 is disposed in the internal space of the hammer case 4 through an opening in the bearing box 24.

[0044] The rotor magnet 34 is fixed to the rotor core 32. The rotor magnet 34 is cylindrical. The rotor magnet 34 is arranged around the rotor core 32.

[0045] The sensor magnet 35 is fixed to the rotor core 32. The sensor magnet 35 has an annular shape. The sensor magnet 35 is disposed on the front end surface of the rotor core 32 and the front end surface of the rotor magnet 34.

[0046] A sensor board 37 is attached to the front insulator 29. The sensor board 37 has a disk-shaped circuit board with a hole in the center and a rotation detection element supported by the circuit board. The rotation detection element detects the position of the sensor magnet 35, thereby detecting the position of the rotor 27 in the rotational direction.

[0047] A pinion gear 41 is formed on the front end of the rotor shaft 33. The pinion gear 41 is connected to at least a part of the reduction mechanism 7. The rotor shaft 33 is connected to the reduction mechanism 7 via the pinion gear 41.

[0048] The reduction mechanism 7 connects the rotor shaft 33 and the spindle 8. 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 27. The reduction mechanism 7 includes a planetary gear mechanism. The reduction mechanism 7 is disposed forward of the motor 6.

[0049] 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.

[0050] When the rotor shaft 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 33.

[0051] The spindle 8 is rotated by the motor 6. The spindle 8 is rotated by the rotational force of the rotor 27 transmitted by the reduction mechanism 7. The spindle 8 is housed in the hammer case 4. The spindle 8 is disposed in front of the motor 6. At least a portion of the spindle 8 is disposed in front of the reduction mechanism 7.

[0052] The spindle 8 has a spindle shaft portion 8A and a flange portion 8B located at the rear of the spindle shaft portion 8A. The spindle shaft portion 8A protrudes forward from the flange portion 8B. The planetary gear 42 is rotatably supported on the flange portion 8B 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.

[0053] The spindle 8 is rotatably supported by a spindle bearing 44. The spindle bearing 44 is held in the bearing box 24.

[0054] The striking mechanism 9 strikes the anvil 10 in the rotational direction based on the rotational force of the spindle 8. The rotational force of the motor 6 is transmitted to the striking mechanism 9 via the speed reducer 7 and the spindle 8. 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 the hammer case 4.

[0055] The hammer 47 strikes the anvil 10 in the rotational direction. The hammer 47 is held by the spindle 8. The hammer 47 is disposed around the spindle shaft portion 8A. A ball 48 is disposed between the spindle 8 and the hammer 47. A coil spring 49 is supported by each of the spindle 8 and the hammer 47.

[0056] The hammer 47 is rotatable together with the spindle 8 based on the rotational force of the spindle 8. 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.

[0057] The ball 48 is made of a metal such as steel. The ball 48 is disposed between the spindle shaft portion 8A and the hammer 47. The spindle 8 has a spindle groove in which at least a portion of the ball 48 is disposed. The spindle groove is provided on a portion of the outer surface of the spindle shaft portion 8A. The hammer 47 has a hammer groove in which at least a portion of the ball 48 is disposed. The hammer groove is provided on a portion of the inner surface of the hammer 47. The ball 48 is disposed between the spindle groove and the hammer groove. The ball 48 can roll inside the spindle groove and inside the hammer groove, respectively. 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 and the hammer groove.

[0058] The coil spring 49 generates an elastic force that moves the hammer 47 forward. The coil spring 49 is disposed between the flange portion 8B and the hammer 47. A recess is provided on the rear surface of the hammer 47. The recess is recessed forward from the rear surface of the hammer 47. A washer 45 is provided inside the recess. The rear end of the coil spring 49 is supported by the flange portion 8B. The front end of the coil spring 49 is supported by the washer 45.

[0059] The anvil 10 is the output part of the impact tool 1 to which the bit is attached. The anvil 10 is disposed in front of the spindle 8. The anvil 10 is connected to the front end of the spindle shaft portion 8A. At least a portion of the anvil 10 is disposed in front of the hammer 47. The anvil 10 has an insertion hole 10C into which the bit is inserted.

[0060] The anvil 10 has an anvil shaft portion 10A and an anvil protrusion portion 10B. The insertion hole 10C is provided so as to extend rearward from the front end portion of the anvil shaft portion 10A. The anvil protrusion portion 10B protrudes radially outward from the rear end portion of the anvil shaft portion 10A.

[0061] The anvil 10 is rotatably supported by an anvil bearing. 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 is held in the hammer case 4. An example of the anvil bearing is a ball bearing.

[0062] At least a portion of the hammer 47 is capable of contacting the anvil protrusion 10B. 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 10B are capable of contacting each other. When the motor 6 is driven while the hammer 47 and the anvil protrusion 10B are in contact with each other, the anvil 10 rotates together with the hammer 47 and the spindle 8.

[0063] 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 anvil 10 cannot be rotated by the power generated by the motor 6 alone, 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 and the hammer groove. 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 10B is released.

[0064] 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 10B while rotating. As a result, the anvil protrusion 10B 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.

[0065] The chuck mechanism 11 is disposed around the front portion of the anvil 10. The chuck mechanism 11 holds the tool bit inserted into the insertion hole 10C.

[0066] The fan 12 generates an airflow for cooling the motor 6. The fan 12 is fixed to the rear of the rotor shaft 33. 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. An air intake 20 is provided in the motor accommodating section 21, and an air exhaust 19 is provided in the rear cover 3. 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 20. The air that has flowed into the internal space of the housing 2 cools the motor 6 by circulating through the internal space of the housing 2. 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 19.

[0067] The battery attachment section 13 is connected to the 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 attachment section 13 is disposed below the battery holding section 23. The battery pack 25 is attached to the battery holding section 23, which is part of the housing 2, via the battery attachment section 13.

[0068] 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 portion 13, the battery pack 25 can supply power to the impact tool 1. The motor 6 is driven based on the power supplied from the battery pack 25. The controller 17 operates based on the power supplied from the battery pack 25.

[0069] In this embodiment, the rated voltage of the battery pack 25 is 18V.

[0070] The trigger switch 14 is operated by an operator to start the motor 6. The trigger switch 14 is provided on the grip portion 22. The trigger switch 14 includes a trigger lever 14A and a switch body 14B. The switch body 14B is housed in the grip portion 22. The trigger lever 14A protrudes forward from the upper front portion of the grip portion 22. When the operator operates the trigger lever 14A, the motor 6 is switched between driving and stopping.

[0071] The forward / reverse switching lever 15 is operated by an operator to switch the rotation direction of the motor 6 from one of the forward direction and the reverse direction to the other. The forward / reverse switching lever 15 is provided on the upper part of the grip portion 22. 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.

[0072] The mode changeover switch 16 is operated by an operator to change the control mode of the motor 6. The mode changeover switch 16 is provided in the battery holding portion 23.

[0073] The controller 17 outputs a control signal that controls at least the motor 6. The controller 17 is housed in the battery holding unit 23. The controller 17 includes a board on which a plurality of electronic components are mounted. Examples of the electronic components mounted on the 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), a transistor, and a resistor.

[0074] [Light unit] 4 is an exploded perspective view from the front showing the light unit 18 according to the embodiment. 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 bit attached to the anvil 10 and the area around the tool bit with the illumination light.

[0075] The light unit 18 is held by the hammer case 4. The light unit 18 is arranged in the front part of the hammer case 4. The light unit 18 is arranged around at least a part of the periphery of the hammer case 4.

[0076] The hammer case 4 has a hammer accommodating portion 4A and a bearing holding portion 4B. The hammer accommodating portion 4A is cylindrical. The hammer accommodating portion 4A is arranged around the striking mechanism 9. The hammer accommodating portion 4A accommodates at least the hammer 47. The bearing holding portion 4B is cylindrical. The bearing holding portion 4B is arranged forward of the hammer accommodating portion 4A. The outer diameter of the bearing holding portion 4B is smaller than the outer diameter of the hammer accommodating portion 4A. The bearing holding portion 4B is arranged around the anvil bearing. The bearing holding portion 4B holds the anvil bearing.

[0077] The light unit 18 is disposed around the bearing holder 4 B. The rear part of the hammer housing 4 A is housed in the motor housing 21 .

[0078] The light unit 18 includes a light emitting element 60 , a light substrate 61 , an optical member 62 , and a light cover 63 .

[0079] The light emitting element 60 is a light source that emits illumination light. An example of the light emitting element 60 is a light emitting diode (LED).

[0080] A plurality of light-emitting elements 60 are provided at intervals around the periphery of the anvil 10. The number of light-emitting elements 60 is, for example, two or more and eight or less. At least three light-emitting elements 60 may be provided. The number of light-emitting elements 60 may be, for example, three or more and six or less. In an embodiment, four light-emitting elements 60 are provided around the periphery of the anvil 10.

[0081] The light board 61 supports a plurality of light emitting elements 60. The light board 61 is arranged at least partially around the periphery of the hammer case 4. In the embodiment, the light board 61 is arranged partially around the periphery of the hammer case 4. The light board 61 is arranged partially around the periphery of the bearing holding portion 4B.

[0082] The light board 61 includes a printed circuit board (PCB). The light board 61 has wiring connected to the light-emitting element 60. Power is supplied to the light-emitting element 60 via the wiring of the light board 61. The light-emitting element 60 is mounted on the front surface of the light board 61. In the embodiment, the light unit 18 includes a surface-mounted (SMD: Surface Mount Device) light-emitting diode. The light-emitting element 60 includes a so-called chip LED.

[0083] The voltage input to one light emitting element 60 is 1.0 V or more and 10.0 V or less. The voltage applied to one light emitting element 60 may be, for example, 2.0 V or more and 8.0 V or less, or 2.5 V or more and 5.0 V or less.

[0084] The current supplied to one light emitting element 60 is 5 mA or more and 100 mA or less. The current supplied to one light emitting element 60 may be 10 mA or more and 50 mA or less, or 15 mA or more and 30 mA or less.

[0085] The luminous flux of the illumination light emitted from one light-emitting element 60 is 1 lm or more and 20 lm or less. The luminous flux of the illumination light emitted from one light-emitting element 60 may be 3 lm or more and 15 lm or less, or may be 5 lm or more and 10 lm or less.

[0086] The luminous intensity of the illumination light emitted from one light-emitting element 60 is 0.5 cd or more and 10 cd or less. The luminous intensity of the illumination light emitted from one light-emitting element 60 may be 1 cd or more and 7 cd or less, or may be 2 cd or more and 5 cd or less.

[0087] As shown in FIG. 4, the outer shape of one light emitting element 60 is substantially a rectangular parallelepiped.

[0088] The width W of one light emitting element 60 is 0.5 mm or more and 3 mm or less. The width W of one light emitting element 60 may be 1 mm or more and 2 mm or less, or 1.2 mm or more and 1.8 mm or less.

[0089] The length L of one light emitting element 60 is 1.5 mm or more and 6 mm or less. The length L of one light emitting element 60 may be 2 mm or more and 5 mm or less, or 2.5 mm or more and 3.5 mm or less.

[0090] The thickness H of one light emitting element 60 is 0.2 mm or more and 2 mm or less. The thickness H of one light emitting element 60 may be 0.3 mm or more and 1 mm or less, or 0.4 mm or more and 0.8 mm or less.

[0091] The optical member 62 is disposed in front of the light emitting element 60 and the light substrate 61. The optical member 62 includes a light transmitting portion 62A through which the illumination light emitted from the light emitting element 60 passes, and a connecting portion 62B connected to the light transmitting portion 62A.

[0092] In the embodiment, the optical member 62 includes an optical member 62L arranged on the left side of the rotation axis AX and an optical member 62R arranged on the right side of the rotation axis AX. The optical member 62L has two light-transmitting portions 62A. The optical member 62R has two light-transmitting portions 62A. Of the four light-emitting elements 60, two light-emitting elements 60 arranged on the left side of the rotation axis AX face the two light-transmitting portions 62A of the optical member 62L, respectively. Of the four light-emitting elements 60, two light-emitting elements 60 arranged on the right side of the rotation axis AX face the two light-transmitting portions 62A of the optical member 62R, respectively.

[0093] The optical member 62 is made of a light-transmitting synthetic resin. In this embodiment, the optical member 62 is made of a polycarbonate resin. The optical member 62 may also be made of an acrylic resin.

[0094] The light transmitting portion 62A has a lens action. The light transmitting portion 62A refracts the illumination light emitted from the light emitting element 60. Note that the light transmitting portion 62A does not necessarily have a lens action.

[0095] The light cover 63 is disposed in front of the light emitting element 60 and the light substrate 61. In the embodiment, the light cover 63 is substantially annular.

[0096] The light cover 63 is made of synthetic resin. The light cover 63 may be made of the same material as the optical member 62. The light cover 63 may be made of a material different from that of the optical member 62. In the embodiment, the light cover 63 is made of polycarbonate resin. The light cover 63 may also be made of acrylic resin. The optical member 62 and the light cover 63 are integrally molded. The optical member 62 and the light cover 63 are integrated by, for example, insert molding.

[0097] In the embodiment, an opening 63A is provided in a part of the light cover 63. The light transmitting portion 62A of the optical member 62 is disposed in the opening 63A of the light cover 63. The light transmitting portion 62A is not covered by the light cover 63. In other words, the light cover 63 is not disposed in front of or behind the light transmitting portion 62A. The connecting portion 62B of the optical member 62 is fixed to the light cover 63.

[0098] The optical member 62 and the light cover 63 are disposed around the bearing holder 4 B. The optical member 62 and the light cover 63 are supported by the hammer case 4 via the hammer case cover 5 .

[0099] The optical member 62 and the light cover 63 protect the light emitting element 60 and the light board 61. The optical member 62 and the light cover 63 prevent contact between the light emitting element 60 and the light board 61 and objects around the impact tool 1. The optical member 62 and the light cover 63 are integrally molded so that no gap is formed between the optical member 62 and the light cover 63. The optical member 62 and the light cover 63 have a waterproof function that prevents moisture from entering the light emitting element 60 and the light board 61. The optical member 62 and the light cover 63 have a dustproof function that prevents dust from entering the light emitting element 60 and the light board 61.

[0100] [Relationship between maximum tightening torque and number of light emitting elements] Fig. 5 is a diagram showing the specifications of impact drivers according to the prior art. Fig. 5 shows the specifications of impact drivers A, B, and C manufactured or sold by company α; D, E, and F manufactured or sold by company β; G, H, and I manufactured or sold by company γ; and J, K, and L manufactured or sold by company δ. Each of products A to L has components equivalent to those of the impact tool 1 described with reference to Figs. 1 to 4. Each of products A to L has a detachable battery pack.

[0101] Examples of specifications for an impact driver include the number of light-emitting elements, the maximum tightening torque of the anvil [Nm], the rated voltage of the battery pack [V], the weight of the impact driver with the battery pack attached [kg], the total length [mm] indicating the distance from the front end of the anvil to the rear end of the motor accommodating section, and the maximum rotation speed of the anvil [rpm].

[0102] As shown in Figure 5, the number of light-emitting elements in product A is three, and similarly, product B has three, product C has three, product D has one, product E has one, product F has one, product G has one, product H has one, product I has one, product J has one, product K has one, and product L has one.

[0103] As shown in Figure 5, the maximum tightening torque of product A is 206 Nm, and similarly, product B is 159 Nm, product C is 147 Nm, product D is 203 Nm, product E is 226 Nm, product F is 181 Nm, product G is 170 Nm, product H is 158 Nm, product I is 181 Nm, product J is 240 Nm, product K is 240 Nm, and product L is 135 Nm.

[0104] As shown in Figure 5, the total length of product A is 134.6 mm, and similarly, product B is 141 mm, product C is 146.1 mm, product D is 133.4 mm, product E is 116.6 mm, product F is 129.5 mm, product G is 144.8 mm, product H is 149.9 mm, product I is 170.18 mm, product J is 152 mm, product K is 168 mm, and product L is 150 mm.

[0105] The rated voltage [V] of the battery pack, the weight [kg] of the impact driver with the battery pack attached, and the maximum rotation speed [rpm] of the anvil are shown in Figure 5.

[0106] In each of products A to L, the rated voltage of the battery pack is approximately 18V.

[0107] Figure 6 is a graph showing the relationship between the maximum anvil tightening torque and the number of light-emitting elements for each of the prior art and the embodiment. In the graph shown in Figure 6, the horizontal axis represents the number of light-emitting elements, and the vertical axis represents the maximum anvil tightening torque. The points shown in Figure 6 are plots of the relationship between the maximum anvil tightening torque and the number of light-emitting elements for each of Products A to L shown in Figure 5.

[0108] In order to prevent a decrease in workability when using the impact tool 1, it is effective to brightly illuminate the work environment with illumination light from the light unit 18. In addition, in order to prevent a decrease in workability when using the impact tool 1, it is effective to shorten the overall length. On the other hand, as the maximum tightening torque increases, the overall length of the impact tool 1 tends to increase. It is important to appropriately set the trade-off relationship between the overall length of the impact tool 1 and the maximum tightening torque.

[0109] As described above, the impact tool 1 is composed of multiple components such as the motor 6, spindle 8, striking mechanism 9, anvil 10, and light unit 18. By optimizing these components, an impact tool 1 is provided that can suppress a decrease in workability. This specification provides an impact tool 1 in which multiple components of the impact tool 1 are optimized, and which has better workability than impact drivers according to known techniques.

[0110] The impact tool 1 according to the embodiment is equipped with a battery pack 25 having a rated voltage of 18 V. As shown by the shaded area in FIG. 6, the impact tool 1 according to the embodiment has a plurality of light-emitting elements 60, and the maximum tightening torque of the anvil 10 is 210 Nm or more. There is no impact driver in the prior art that is equipped with a battery pack 25 having a rated voltage of 18 V, has a plurality of light-emitting elements, and has a maximum tightening torque of the anvil 10 of 210 Nm or more. The maximum tightening torque of the anvil 10 may be 210 Nm or more and 300 Nm or less.

[0111] Furthermore, the impact tool 1 according to the embodiment has four light-emitting elements 60, and the maximum tightening torque of the anvil 10 is 180 Nm or more. There is no impact driver in the prior art that is equipped with a battery pack 25 with a rated voltage of 18 V, has four light-emitting elements, and has a maximum tightening torque of the anvil 10 of 180 Nm or more. The maximum tightening torque of the anvil 10 may be 180 Nm or more and 300 Nm or less.

[0112] [Relationship between total length and number of light-emitting elements] Furthermore, in order to prevent a decrease in workability when using the impact tool 1, it is effective to optimize the overall length of the impact tool 1. As shown in Fig. 1, the overall length La of the impact tool 1 is the distance from the front end of the anvil 10 to the rear end of the motor housing 200 (the rear end of the rear cover 3).

[0113] Fig. 7 is a graph showing the relationship between the total length of the impact tools according to the prior art and the embodiment and the number of light-emitting elements. In the graph shown in Fig. 7, the horizontal axis represents the number of light-emitting elements, and the vertical axis represents the total length of the impact tool. The points shown in Fig. 7 are plots of the relationship between the total length of the impact tools according to the A product to the L product shown in Fig. 5 and the number of light-emitting elements.

[0114] The impact tool 1 according to the embodiment is equipped with a battery pack 25 having a rated voltage of 18 V. As shown by the hatched area in Fig. 7, the impact tool 1 according to the embodiment has a plurality of light-emitting elements 60, and has an overall length La of 100 mm or less. There is no impact driver in the prior art that is equipped with a battery pack 25 having a rated voltage of 18 V, has a plurality of light-emitting elements, and has an overall length of 100 mm or less.

[0115] In the impact tool 1 having a plurality of light emitting elements 60 and having a maximum tightening torque of the anvil 10 of 1,000 Nm or more and 2,500 Nm, the overall length La of the impact tool 1 may be 155 mm or less.

[0116] [Impact tool weight and maximum anvil rotation speed] In addition, in order to suppress a decrease in workability when using the impact tool 1, it is effective to optimize the weight of the impact tool 1. In the embodiment, the weight of the impact tool is the weight of the impact tool with the battery pack attached. In addition, in order to suppress a decrease in workability when using the impact tool 1, it is effective to optimize the maximum rotation speed of the anvil 10.

[0117] In this embodiment, the weight of the impact tool 1 is 1.5 kg or less, and the maximum rotation speed of the anvil 10 is 3,000 rpm or less.

[0118] [effect] As described above, in this embodiment, the impact tool 1 includes the motor 6, which is a brushless motor, the spindle 8 rotated by the motor 6, the hammer 47 held by the spindle 8, the anvil 10 struck in the rotational direction by the hammer 47, the resin motor housing 200 that houses the motor 6, the hammer case 4 connected to the motor housing 200 and housing the hammer 47 and the spindle 8, and the battery holder 23 connected to the motor housing 200 and to which the battery pack 25 rated at 18 V is attached. The impact tool 1 includes a light unit 18 held by the hammer case 4 and having a plurality of light-emitting elements 60. The overall length La, which indicates the distance from the front end of the anvil 10 to the rear end of the motor housing 200, is 100 mm or less. The maximum tightening torque of the anvil 10 is 210 Nm or more.

[0119] In the above configuration, the light unit 18 has a plurality of light-emitting elements 60, so the work environment is brightly illuminated with illumination light. Also, the overall length La, which indicates the distance from the front end of the anvil 10 to the rear end of the motor housing 200, is 100 mm or less, and the maximum tightening torque of the anvil 10 is 210 Nm or more. Therefore, deterioration in workability when using the impact tool 1 is suppressed.

[0120] In this embodiment, at least three light emitting elements 60 are provided.

[0121] In the above configuration, the light unit 18 has at least three light emitting elements 60, so the work environment is brightly illuminated with illumination light, thereby preventing a decrease in workability when using the impact tool 1.

[0122] In an embodiment, the impact tool 1 weighs 1.5 kg or less.

[0123] In the above configuration, the weight of the impact tool 1 with the battery pack 25 attached is 1.5 kg or less, so that the deterioration of workability when using the impact tool 1 is suppressed.

[0124] In an embodiment, the maximum rotation speed of the anvil 10 is 3,000 rpm or less.

[0125] In the above configuration, the maximum rotation speed of the anvil 10 is 3,000 rpm or less, so that the deterioration of workability when using the impact tool 1 is suppressed.

[0126] In the embodiment, the light unit 18 is arranged around at least a portion of the periphery of the hammer case 4 and has a light substrate 61 supporting a plurality of light-emitting elements 60, and an optical member 62 arranged in front of the light-emitting elements 60 and the light substrate 61.

[0127] In the above configuration, the light emitting element 60 and the light substrate 61 are protected by the optical member 62 .

[0128] In this embodiment, the impact tool 1 includes a motor 6, which is a brushless motor, a spindle 8 rotated by the motor 6, a hammer 47 held by the spindle 8, an anvil 10 struck in the rotational direction by the hammer 47, a resin motor housing 200 that houses the motor 6, a hammer case 4 connected to the motor housing 200 and that houses the hammer 47 and the spindle 8, and a battery holder 23 connected to the motor housing 200 and to which a battery pack 25 with a rated voltage of 18 V is attached. The impact tool 1 includes a light unit 18 held by the hammer case 4 and having four light-emitting elements 60. The maximum tightening torque of the anvil 10 is 180 Nm or more.

[0129] In the above configuration, the light unit 18 has four light-emitting elements 60, so the work environment is brightly illuminated with illumination light. Also, the maximum tightening torque of the anvil 10 is 180 Nm or more. Therefore, the deterioration of workability when using the impact tool 1 is suppressed.

[0130] [Variations] 8, 9, and 10 are diagrams each schematically showing a modified example of the light board 61 according to the embodiment. As shown in FIG. 8, the light board 61A may be ring-shaped. As shown in FIG. 9, the light board 61B may be arc-shaped. A gap 61G is provided between one end and the other end of the light board 61B. As shown in FIG. 10, the gap 61G between one end and the other end of the light board 61C may be large.

[0131] In the above-described embodiment, the rated voltage of the battery pack 25 attached to the battery holder 23 may be 36 V. In an impact tool 1 to which a battery pack 25 with a rated voltage of 36 V is attached, the overall length La, which indicates the distance from the front end of the anvil 10 to the rear end of the motor housing 200, may be 110 mm or less, and the maximum tightening torque of the anvil 10 may be 200 Nm or more. Even in the above configuration, the light unit 18 includes a plurality of light-emitting elements 60, so the work environment is brightly illuminated with illumination light. Furthermore, since the overall length La, which indicates the distance from the front end of the anvil 10 to the rear end of the motor housing 200, is 110 mm or less, and the maximum tightening torque of the anvil 10 is 200 Nm or more, a decrease in workability when using the impact tool 1 is suppressed.

[0132] In the above-described embodiment, the impact tool 1 is an impact driver. The impact tool 1 may be an impact wrench.

[0133] In the above-described embodiment, the power source for the impact tool 1 does not have to be the battery pack 25, and may be a commercial power source (AC power source). [Explanation of symbols]

[0134] 1...impact tool, 2...housing, 3...rear cover, 2L...left housing, 2R...right housing, 2S...screw, 4...hammer case, 4A...hammer housing section, 4B...bearing holding section, 5...hammer case cover, 6...motor, 7...reduction mechanism, 8...spindle, 8A...spindle shaft section, 8B...flange section, 9...impact mechanism, 10...anvil, 10A...anvil shaft section, 10B...anvil protrusion section, 10C...insertion hole, 11...chuck mechanism, 12...fan, 13...battery mounting section, 14...trigger switch, 14A...trigger lever, 14B...switch body, 15...forward / reverse switching lever, 16...mode switching switch, 17...controller, 18...light unit, 19...exhaust port, 20...intake 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, 30... rear insulator, 31... coil, 32... rotor core, 33... rotor shaft, 34... rotor magnet, 35... sensor magnet, 37... sensor board, 39... rotor bearing, 41... pinion gear, 42... planetary gear, 42P... pin, 43... internal gear, 44... spindle bearing, 45... washer , 47...Hammer, 48...Ball, 49...Coil spring, 60...Light emitting element, 61...Light board, 61A...Light board, 61B...Light board, 61C...Light board, 61G...Gap, 62...Optical member, 62A...Light transmitting portion, 62B...Connecting portion, 62L...Optical member, 62R...Optical member, 63...Light cover, 63A...Opening, 200...Motor housing, AX...Rotating shaft, H...Thickness, L...Length, La...Total length, W...Width.

Claims

1. a brushless motor having a stator and a rotor that rotates around a rotation axis extending in the front-rear direction; a spindle that is disposed forward of the brushless motor and that is rotated by the brushless motor; a speed reduction mechanism at least a portion of which is disposed between the rotor and the spindle and which transmits rotation of the rotor to the spindle; a hammer held by the spindle; an anvil, at least a portion of which is disposed in front of the spindle and which is struck in a rotational direction by the hammer; a resin motor housing that houses the brushless motor; a hammer case connected to the motor housing, accommodating at least a portion of the reduction gear mechanism, the hammer, the spindle, and the anvil, the hammer case including a hammer accommodating portion accommodating the hammer, and a bearing holding portion disposed forward of the hammer accommodating portion, having an outer diameter smaller than an outer diameter of the hammer accommodating portion, and holding a bearing of the anvil; a grip portion protruding downward from the motor housing; a battery holding portion connected to a lower end of the grip portion and to which a battery pack is attached; a light unit held by the hammer case, the light unit comprising: a light board arranged at least partly around the bearing holding portion; a plurality of light-emitting elements mounted on the front surface of the light board and spaced apart around the rotation shaft; an optical member made of a first material, the optical member having light-transmitting portions arranged in front of the plurality of light-emitting elements so as to face each other and spaced apart from each other; and a light cover made of a second material different from the first material, the optical member having openings arranged in front of the plurality of light-emitting elements and spaced apart from each other, the light-transmitting portions arranged in front of each of the plurality of light-emitting elements and spaced apart from each other, the light cover being integrally molded with the optical member; The rated voltage of the battery pack is 18 V, the number of the light-emitting elements is four, and the luminous flux of the illumination light emitted from one of the light-emitting elements is 5 lm or more and 10 lm or less, and the distance from the front end of the anvil to the rear end of the motor housing is 100 mm or less, and the maximum tightening torque of the anvil is 180 Nm or more and 300 Nm or less. Impact tool.

2. a voltage input to one of the light-emitting elements is 1.0 V or more and 10.0 V or less, and a current supplied to one of the light-emitting elements is 5 mA or more and 100 mA or less; The impact tool according to claim 1 .

3. The weight is 1.5 kg or less. The impact tool according to claim 1 .

4. The maximum rotation speed of the anvil is 3,000 rpm or less. The impact tool according to claim 1 .

5. a brushless motor having a stator and a rotor rotatable relative to the stator; a planetary gear rotated by the rotor; a spindle rotated by the planetary gear; a hammer held by the spindle; an anvil that is struck in a rotational direction by the hammer; a resin motor housing that houses the brushless motor; a hammer case connected to the motor housing and accommodating the hammer and the spindle; a battery holding portion connected to the motor housing and adapted to hold a battery pack having a rated voltage of 18 V; a light unit including: an optical member made of a first material, the optical member having at least four light-emitting elements held by the hammer case and arranged at intervals around the hammer case; lenses arranged in front of the at least four light-emitting elements so as to face each other and spaced apart; a printed wiring board having a front surface on which the light-emitting elements are mounted; and a light cover made of a second material different from the first material, the light cover having openings arranged in front of each of the lenses and spaced apart from each other, the light cover being arranged in front of each of the lenses and having openings in which the lenses are arranged one by one, the light cover being made of a second material different from the first material, and integrally molded with the optical member; The maximum tightening torque of the anvil is 180 Nm or more and 300 Nm or less, Each of the light-emitting elements has a width of 0.5 mm to 3 mm, a length of 1.5 mm to 6 mm, a thickness of 0.2 mm to 2 mm, a luminous flux of 1 lm to 20 lm, an input voltage of 1.0 V to 10.0 V, and a supplied current of 5 mA to 100 mA. Impact tool.

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