JP2012139749A - Power tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a miniaturized power tool of high cooling efficiency.SOLUTION: A motor provided with a stator and a rotor rotatable in relation to the stator are housed in the housing of a power tool. Further, a part of the output portion driven by the motor is housed in the housing. The stator includes a stator core provided with a protruded part, an insulator provided with a projection part abutting on the protruded part and connected to the stator core, and a coil fixed to the insulator. The insulator insulates the coil from the stator core.

Description

  The present invention relates to a power tool.

  Conventionally, an electric power tool driven by electric power supplied from an AC power source to a commutator motor, for example, an impact driver is known (see, for example, Patent Document 1).

JP 2008-126344 A

  A conventional impact driver mainly includes a motor, a housing that houses the motor, and an output unit that is housed in the housing and receives a driving force from the motor. The motor mainly includes a cooling fan, a stator, and a rotor that can rotate with respect to the stator, and the stator includes a stator core, an insulator connected to the stator core, and a coil fixed to the insulator. Yes.

  The stator core and the insulator are connected to each other by inserting a protrusion provided on the insulator into a hole formed in the stator core. One of the factors that determine the output of the motor is the magnetic flux generated by the coil. Since this magnetic flux is determined by the volume of the stator core, there is a concern that the magnetic flux generated in the motor is reduced by forming a hole in the stator core. Further, since the stator core of the motor used for the impact driver is originally small, the effect of the volume reduced by the hole on the output of the motor is remarkable. Therefore, in order to obtain a desired output, the size of the stator core has to be increased, and downsizing of the impact driver has been difficult.

  Further, in the conventional impact driver, the housing is formed with two intake ports for taking outside air by a cooling fan and an exhaust port for discharging cooling air. More specifically, one intake port is formed on the opposite side (rear side) of the output portion with respect to the motor, and the other intake port is formed in a direction (side) perpendicular to the rotation axis of the motor. . The exhaust port is formed radially outward of the rotation axis of the cooling fan.

  Since the conventional impact driver has two intake ports, smooth cooling is achieved by the collision between the cooling air taken in from one air intake and the cooling air taken in from another air intake. The wind flow was obstructed. This reduced the cooling efficiency of the motor.

  Accordingly, an object of the present invention is to provide a miniaturized electric tool with high cooling efficiency.

  In order to achieve the above object, the present invention includes a housing, a stator, and a rotor that is rotatable with respect to the stator, a motor that is housed in the housing, and an output unit that is driven by the motor. The stator includes a stator core provided with a convex portion, an insulator provided with a projection that can contact the convex portion and connected to the stator core, and fixed to the insulator. And a coil to be provided.

  According to such a configuration, since the stator core and the insulator are fitted by the protrusions and the projections coming into contact with each other, the insulator can be fixed to the stator core without making a hole or the like in the stator core. As a result, it is possible to prevent a decrease in magnetic flux due to the holes in the stator core, so that the motor power can be improved even with a motor of the same size as the conventional motor. In addition, this makes it possible to reduce the size of the motor, thereby reducing the size of the product.

  Furthermore, it is preferable that a plurality of the protrusions are provided.

  According to such a configuration, since the plurality of protrusions are provided, the stator core and the insulator can be more firmly fixed.

  Furthermore, it is preferable that the stator core has a substantially cylindrical shape, the convex portion is provided on the outer peripheral surface of the stator core, and the protrusion is provided on the outer peripheral surface of the insulator.

  According to such a configuration, since the convex portion is provided on the outer peripheral surface of the stator core and the protrusion is provided on the radially outer surface of the insulator, the stator core is compared with the case where it is provided inside the stator core. It is possible to effectively use the internal space. As a result, the number of turns of the coil can be increased, and the motor power can be improved. Then, the size of the motor can be reduced, so that the product can be reduced in size.

  Further, the housing is composed of a first housing and a second housing, and the stator core is held in the housing by contacting the convex portion with the first housing and the second housing. Is preferred.

  According to such a configuration, since the stator core is supported by the first housing and the second housing by the convex portion, the convex portion is used as a member for fixing the insulator to the stator core and also used as a member for fixing the stator core to the housing. Has been. This makes it possible to fix the stator core to the housing without providing a new fixing member.

  Furthermore, it is preferable that a plurality of axially extending slots are formed on the inner surface of the stator core side by side in the circumferential direction, and insulating paper is disposed on the entire inner peripheral surface of each of the slots. .

  Furthermore, it is preferable that the insulator is provided so as to be in contact with an axial end surface of the stator core.

  According to such a configuration, since the insulating paper is disposed over the entire inner peripheral surface of the slot, the stator core and the coil can be reliably insulated by the insulating paper. Further, as compared with the case where the stator core and the coil are insulated by the insulator, the space in the slot can be secured more widely when the insulation paper is insulated, and the number of turns of the coil can be increased. As a result, the motor power can be improved and the size of the motor can be reduced, so that the product can be reduced in size.

  In another aspect of the present invention, a motor including a housing having an air inlet and an air outlet, a motor housed in the housing and fixed to the output shaft and the cooling shaft, and driven by the output shaft. An electric power tool having an output part that is arranged alongside the motor in the housing and is partially exposed to the outside, wherein the intake port is only on the opposite side of the output part with respect to the motor The electric power tool is provided, wherein the exhaust port is formed radially outward of the cooling fan.

  According to such a configuration, since the intake port is formed only on the opposite side of the output unit with respect to the motor, there is no collision of airflow as compared with the case where the intake port is formed at a plurality of locations. Thereby, it becomes possible to take in outside air smoothly and to raise the cooling efficiency of a motor.

  Further, it is preferable that the motor is a brushless motor, and a plurality of switching elements for energizing the motor are arranged between the motor and the intake port.

  According to such a configuration, since the switching element is arranged between the air inlet and the motor, the switching element can be simultaneously cooled by the rotation of the cooling fan.

  Furthermore, it is preferable that the switching element is a substantially rectangular parallelepiped, and is arranged so that the longitudinal direction of the substantially rectangular parallelepiped is parallel to the axial direction of the output shaft.

  According to such a configuration, since the longitudinal direction of the switching element is parallel to the axial direction, the switching element can be efficiently cooled.

  Furthermore, it is preferable that the switching element is disposed at a position overlapping the intake port when viewed in the axial direction of the output shaft.

  Furthermore, the cooling fan is preferably a centrifugal fan.

  According to such a configuration, since the intake port and the switching element are arranged so as to overlap each other when viewed in the axial direction, the switching element can be efficiently cooled.

  According to another aspect of the present invention, a housing, a stator, and a rotor rotatable with respect to the stator, a motor housed in the housing, and an output unit driven by the motor, The stator includes a stator core having an engaging portion, an insulator provided with an engaged portion engageable with the engaging portion and connected to the stator core, and fixed to the insulator. And a coil having a coil.

  According to the present invention, it is possible to provide a miniaturized electric tool with high cooling efficiency.

Sectional drawing of the impact driver of this invention. The external view of the impact driver of this invention. The rear view of the impact driver of this invention. The figure for demonstrating the positional relationship of the inlet port and switching element of the impact driver of this invention. The side view of the motor of the impact driver of this invention. The front view of the motor of the impact driver of this invention. Sectional drawing of the VV line | wire in FIG. 4 of the motor of the impact driver of this invention. Sectional drawing of the stator core of the motor of the impact driver of this invention. The exploded perspective view of the stator core of the motor of the impact driver of the present invention. The front view of the inverter circuit board of the impact driver of this invention. The rear view of the inverter circuit board of the impact driver of this invention. The side view of the inverter circuit board of the impact driver of this invention. The side view of the hammer case of the impact driver of this invention. The front view of the hammer case of the impact driver of this invention. The perspective view of the hammer case of the impact driver of this invention. The disassembled perspective view of the light periphery of the impact driver of this invention. The top view of the board | substrate accommodating part of the impact driver of this invention. The top view of the control circuit board of the impact driver of this invention. The bottom view of the control circuit board of the impact driver of this invention. The top view of the power supply circuit board of the impact driver of this invention. The side view of the power supply circuit board of the impact driver of this invention. The control block diagram of the impact driver of this invention. The partial enlarged view of the light periphery of the impact driver of the modification of this invention. The partial enlarged view of the light periphery of the impact driver of the modification of this invention. The side view of the hammer case of the conventional impact driver. The front view of the hammer case of the conventional impact driver. The perspective view of the hammer case of the conventional impact driver.

  Hereinafter, as an example of the electric tool of the present invention, the configuration of the impact driver 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 13.

  As shown in FIG. 1, the impact driver 1 mainly includes a housing 2, a motor 3, a gear mechanism 4, a hammer 5, an anvil 6, a light 7, a control unit 8, and a power cord 9. It is configured. A tip tool 10 is detachably attached to the anvil 6.

  The outer shell of the impact driver 1 includes a housing 2 and a resin cover 21. A metal hammer case 22 is accommodated in the cover 21, and a part of the hammer case 22 is exposed to the outside (FIG. 2). The cover 21 is fixed to the hammer case 22 by a stopper 22A. The housing 2 includes a body part 23, a handle part 24, and a substrate housing part 25. The body portion 23 has a substantially cylindrical shape, and accommodates the motor 3, the gear mechanism 4, the hammer 5, and the anvil 6 in this order in cooperation with the cover 21 and the hammer case 22. In the following description, the anvil 6 is defined as the front side, and the motor 3 side is defined as the rear side. In addition, the direction in which the handle portion 24 extends with respect to the body portion 23 is defined as the downward direction, and the opposite is defined as the upward direction. Further, the front side in the drawing in FIG. 1 is defined as the right direction, and the opposite is defined as the left direction.

  As shown in FIGS. 3A and 3B, the housing 2 is a split housing that can be divided in the left-right direction. The housing 2 includes a first housing 2A that forms the right half and a second housing 2B that forms the left half. Yes. As shown in FIG. 2, the first housing 2A and the second housing 2B are fixed to each other by a plurality of screws 2C. A plurality of air inlets 23a for taking in outside air are formed on the rear end surface of the body portion 23, and a plurality of air holes for discharging outside air taken into the first housing 2A and the second housing 2B are discharged on the side surfaces of the body portion 23. The exhaust port 23b is formed. The intake port in the housing 2 is only the intake port 23 a formed in the rear end surface of the housing 2.

  The handle portion 24 is provided with a trigger 26, and the trigger 26 is connected to a switch mechanism 27 accommodated in the handle portion 24. Supply of electric power to the motor 3 and interruption are switched by the trigger 26. A changeover switch 28 for switching the rotation direction of the motor 3 is provided at the connection portion between the handle portion 24 and the body portion 23 and immediately above the trigger 26.

  The substrate accommodating portion 25 accommodates the control portion 8, and the power cord 9 extends downward. The substrate housing portion 25 has a protruding portion 25A that protrudes in the direction (front) in which the tip tool 10 protrudes from the anvil 6. A striking force display panel 81, which will be described later, is provided on the surface (upper surface) of the protruding portion 25A on the handle portion 24 side.

  The motor 3 is a brushless motor and includes an output shaft 31 that extends in the front-rear direction, a rotor 32 that is fixed to the output shaft 31 and includes a plurality of permanent magnets, and a stator that is disposed so as to surround the rotor 32 and a plurality of coils 33. 34 and a cooling fan 35 fixed to the output shaft 31. A detailed configuration of the motor 3 will be described later.

  The gear mechanism 4 is a speed reduction mechanism constituted by a planetary gear mechanism having a plurality of gears, and reduces the rotation of the output shaft 31 and transmits it to the hammer 5.

  The hammer 5 has a collision part 51 at the front end, and the anvil 6 has a collision part 61 at the rear end. Further, the hammer 5 is urged forward by a spring 52 so that the collision part 51 collides with the colliding part 61 in the rotation direction when rotating. With such a configuration, when the hammer 5 rotates, the anvil 6 is hit.

  Further, the hammer 5 is configured to be able to move backward against the urging force of the spring. After the collision between the collision part 51 and the colliding part 61, the hammer 5 resists the urging force of the spring. Retreat while rotating. When the collision part 51 gets over the collision part 61, the elastic energy stored in the spring is released, the hammer 5 moves forward, and the collision part 51 and the collision part 61 collide again. .

  The light 7 is held by a cover 21. A detailed configuration of the light 7 will be described later. The control unit 8 is accommodated in the substrate accommodation unit 25, and a part of the elements of the control unit 8 is also accommodated in the handle unit 24. The controller 8 controls the rotational speed of the motor 3 by adjusting the amount of power supplied to the motor 3 according to the operation amount of the trigger 26. The detailed configuration of the control unit 8 will be described later. The power cord 9 supplies power to the motor 3 and the control unit 8 by connecting to a power source (not shown).

  As shown in FIG. 6, the stator 34 further includes a substantially cylindrical stator core 36 and insulators 37 provided at both axial ends of the stator core 36. Inside the stator core 36, six teeth 36A are provided in the circumferential direction so as to protrude radially inward, and slots 36a are defined between the teeth 36A (FIG. 5C). That is, six slots 36a are formed side by side in the circumferential direction, similarly to the teeth 36A. An insulating paper 38 for insulating the coil 33 and the stator core 36 is provided on the entire inner peripheral surface of the slot 36a (FIGS. 5A and 5B). Four convex portions 36B are provided on the outer peripheral surface of the stator core 36 so as to protrude outward in the radial direction, and a contact surface 36C that is a side surface in the circumferential direction is defined on each convex portion 36B. . The stator core 36 is supported by the housing 2 by fitting a concave portion (not shown) provided in each of the first housing 2A and the second housing 2B and a convex portion 36B. That is, the stator core 36 is supported by the housing 2 from the left-right direction. The convex portion 36B is supported by the housing 2 and at the same time plays a role of fixing the insulator 37 as will be described later.

  The insulators 37 are provided at both axial ends of the stator core 36 to insulate the coil 33 and the stator core 36, and six insulator-side teeth 37C are arranged in the circumferential direction so as to protrude radially inward. Is provided. Four protrusions 37A are provided on the outer peripheral surface of the insulator 37 so as to protrude outward in the radial direction. Each projecting portion 37A has a contacted portion 37B which is a circumferential side surface and can contact the contact portion 36C. In a state where the front and rear end surfaces of each insulator 37 are attached to the stator core 36 so as to contact the front and rear end surfaces of the stator core 36, the respective contact portions 36C are in contact with the contacted portions 37B, respectively. 36 is not rotatable in the circumferential direction (FIGS. 5A to 5C). Further, since the fitting between the four protrusions 37 </ b> A and the stator core 36 is set tightly, the insulator 37 cannot move in the axial direction with respect to the stator core 36. At this time, each of the teeth 36A and each of the insulator-side teeth 37C coincide with each other in the circumferential direction.

  A coil 33 is fixed to the insulator 37. More specifically, as shown in FIG. 5A, the coil 33 started to be wound from the insulator-side teeth 37C of one insulator 37 among the insulators 37 provided at both ends of the stator core 36 passes through the slot 36a and others. After being hooked on the insulator-side teeth 37C of the insulator 37, the insulator 37 passes through the slot 36a and reaches one insulator 37 again. By repeating this operation a plurality of times, the coil 33 is wound around the insulator 37. At this time, the coil 33 is reliably insulated from the stator core 36 by the insulator 37 and the insulating paper 38. During the operation of winding the coil 33 around the insulator 37, if the position of the insulator 37 and the stator core 36 is displaced, the coil 33 cannot be wound, so that the insulator 37 and the stator core 36 are securely fixed. There is a need. In the present embodiment, the stator core 36 and the insulator 37 are securely fixed by the four protrusions 36B and the four protrusions 37A.

  The cooling fan 35 is a centrifugal fan, and discharges air taken in from the axial direction of the output shaft 31 outward in the radial direction. The exhaust port 23b is formed at a position corresponding to the radially outer side of the cooling fan 35 in the body portion 23 (FIG. 2).

  An inverter circuit board 39 is arranged between the motor 3 and the air inlet 23a formed in the housing 2 (on the rear side of the motor 3) so as to extend in the vertical direction. As shown in FIGS. 7A to 7C, on the inverter circuit board 39, six substantially rectangular parallelepiped switching elements 39 </ b> A for controlling the power supplied to the coil 33 have a longitudinal direction parallel to the axial direction of the output shaft 31. Is arranged. A through hole 39 a through which the output shaft 31 passes is formed in a substantially central portion of the inverter circuit board 39. Three Hall elements 39B for detecting the position of the rotor 32 are spaced by 60 ° on the surface (motor side surface) opposite to the side on which the switching element 39A of the inverter circuit board 39 is provided. Are arranged. The arrows shown in the wirings in FIGS. 7B and 7C indicate the flow of electricity. In other words, FIG. 7B shows that power is supplied from the switch mechanism 27 to the inverter circuit board 39. As shown in FIG. 3B, the switching element 39 </ b> A is provided at a position that overlaps with the intake port 23 a when viewed in the axial direction of the output shaft 31.

  The light 7 is an LED (light emitting diode), the front is supported by a plurality of ribs 21A provided on the cover 21 (FIG. 9), and the rear is supported by the housing 2 (body part 23) (FIG. 1). At this time, the light 7 and the hammer case 22 are separated from each other. Since the hammer case 22 is made of metal and the tip portion is exposed to the outside (FIG. 2), static noise may occur in the exposed portion. However, in the present embodiment, since the light 7 and the hammer case 22 are separated from each other, the light 7 is not easily affected by electrostatic noise. The light 7 is turned on by pressing a light button 81A described later, and the light illuminates the periphery of the tip tool 10 through a hole 21a (FIG. 9) formed in the cover 21. Thereby, the worker can work with the light 7 in the dark.

  The control unit 8 includes a striking force display panel 81, a control circuit board 82, and a power supply circuit board 83. The striking force display panel 81 is provided on the surface (upper surface) of the protruding portion 25A on the handle portion 24 side. As shown in FIG. 10, the striking force display panel 81 includes a light button 81A, a striking force switching button 81B, a striking force level display portion 81C, a mode switching button 81D, and a mode display portion 81E. Yes.

  The operator can change the impact force of the tip tool 10 by changing the rotation speed of the motor 3 with the impact force switching button 81B. The striking force can be adjusted in four stages (25%, 50%, 75%, 100% of the rated speed of the motor 3), and the set striking force is displayed on the striking force level display portion 81C. Once set, the striking force is reset when the power supply from the power cord 9 is cut off, and when the power is supplied again, the striking force is 100% (100%, all four striking force level display parts 81C are lit). Will be reset.

  The striking force level display portion 81C also functions as an energizing lamp. When power is supplied from the power cord 9, the striking force level display portion 81C is fully lit. Even when the striking force is changed by the striking force switching button 81B, at least one of the striking force level display portions 81C is always lit, so that the operator can check whether the impact driver 1 is energized. This can be confirmed by the lighting of the striking force level display portion 81C. More specifically, it is determined whether power is supplied to the control circuit board 82 by a microcomputer 82B described later. Thereby, even if power is supplied to the power cable 9, even if the power circuit board 83 is abnormal and power is not supplied to the control circuit board 82, the striking force display panel 81 does not light up. Therefore, an abnormality in the power supply circuit board 83 can be recognized by the lighting of the striking force display panel 81.

  The mode switching button 81D is a button for switching whether the motor 3 is operated continuously (continuous) or whether the motor 3 is operated only once (single). When set to continuous, the motor 3 operates continuously while the trigger 26 is being pulled. At this time, “continuous firing” is lit in the mode display portion 81E. If it is set to single, the motor 3 stops when the hammer 5 and the anvil 6 collide with each other a predetermined number of times. A shock sensor 82A, which will be described later, is provided on the control circuit board 82, and vibration is detected by the shock sensor 82A, and the number of collisions between the hammer 5 and the anvil 6 is detected by this vibration. At this time, “single shot” is lit on the mode display portion 81E.

  The control circuit board 82 is disposed in the board housing part 25 at a position closest to the handle part 24 (FIG. 1). The striking force display panel 81 is located immediately above the control circuit board 82. As shown in FIGS. 11A and 11B, the control circuit board 82 includes a shock sensor 82A for detecting the number of collisions between the hammer 5 and the anvil 6, a microcomputer 82B for controlling the entire impact driver 1, and a striking force display panel 81. And a panel control unit 82C corresponding to the above. The panel control unit 82C includes a plurality of buttons and LEDs, and the arrangement of each element corresponds to the arrangement of each button and display unit in the striking force display panel 81 (FIG. 10). The surface of the control circuit board 82 is covered with silicon for insulation. As shown in FIG. 13, the microcomputer 82 </ b> B is connected to the switch mechanism 27, and controls the rotation speed of the motor 3 according to the pulling margin of the trigger 26 input from the switch mechanism 27. Specifically, a signal from the Hall element 39B is received, and a PWM (Pulse Width Modulation) control signal for driving the switching element 39A of the inverter circuit board 39 is output to the switching element 39A of the inverter circuit board 39. Yes.

  The power circuit board 83 is disposed in the board housing portion 25 and between the power cord 9 and the control circuit board 82 (FIG. 1). As shown in FIGS. 12A and 12B, the power supply circuit board 83 generates noise generated from a diode bridge 83 </ b> A for full-wave rectification of the AC power supplied from the power cord 9 and AC 100 V power supplied from the power cord 9. Choke coil 83B for removing, first capacitor 83C for removing noise generated by switching element 39B (FIG. 13), second capacitor 83D for smoothing the full-wave rectified current, and control And an IPD element 83E for generating power to be supplied to the circuit board 82. The arrows shown in the wirings in FIGS. 12A and 12B indicate the flow of electricity. The power circuit board 83 is covered with an outer surface of a container 84 whose upper side is substantially C-shaped in cross section, and the container 84 is filled with urethane. That is, the power circuit board 83 and each element on the power circuit board 83 are fixed by urethane and at the same time are insulated, vibration-proof and waterproof. Since the container 84 is filled with urethane, it is heavier than other substrates.

  The diode bridge 83 </ b> A is a rectangular parallelepiped, and is disposed on the power supply circuit board 83 so that the longitudinal direction thereof is parallel to the power supply circuit board 83. As a result, the space of the power supply circuit board 83 occupying the board housing portion 25 can be minimized. The choke coil 83B and the first capacitor 83C are larger in volume and weight than other elements, and are accommodated in the handle portion 24 (FIG. 1). In the present embodiment, in order to prevent the temperature of the handle portion 24 from increasing, a film capacitor that does not easily generate heat is employed as the first capacitor 83C. In the impact driver 1, a metal member such as the motor 3 and the gear mechanism 4 is disposed on one end side (upper side) of the handle portion 24 held by an operator, and the other end (lower side) has a heavy power source among the boards. The circuit board 83 and the control circuit board 82 are arranged, and the choke coil 83B and the first capacitor 83C, which are heavy elements, are arranged near the board accommodating part 25 in the handle part 24 to thereby balance the weight of the impact driver 1 as a whole. Keeps good. Specifically, each member is arranged so that the center of gravity is located immediately above the handle portion 24 held by the operator.

  The AC 100V power supplied from the power cord 9 is rectified by the diode bridge 83A, and then partially reduced to 18V by the IPD element 83E and supplied to the control circuit board 82 as a driving power. The remainder is boosted to 140 V as a power source for driving the motor 3 and supplied to the inverter circuit board 39 via the switch mechanism 27. In the housing 2, the power cord 9, the power circuit board 83, the control circuit board 82, the switch mechanism 27, and the inverter circuit board 39 are accommodated in this order from bottom to top. Thus, since the flow of electricity from the power cord 9 to the motor 3 and the arrangement of each member in the housing 2 match, wiring between the substrates can be performed efficiently.

  Next, the operation of the impact driver 1 will be described. By connecting the power cord 9 to a power source (not shown), the driving power is supplied to the microcomputer 82B of the control circuit board 82, and the striking force level display portion 81C is fully lit. When the operator pulls the trigger 26 in this state, the motor 3 rotates at a rotational speed corresponding to the pulling allowance. At the same time, the cooling fan 35 also rotates to take outside air from the intake port 23a. The outside air cools the switching element 39A, the inverter circuit board 39, and the motor 3, and is discharged to the outside from the exhaust port 23b. As the motor 3 rotates, the hammer 5 strikes the anvil 6 and the tip tool 10 rotates. When the operator releases the trigger 26, the motor 3 stops. By pulling the power cord 9 from a power source (not shown), the striking force level display portion 81C is turned off.

  According to such a configuration, since the striking force level display portion 81C is provided on the handle portion 24 side of the protruding portion 25A, it is easy for an operator to confirm the display of the striking force display portion 81C.

  According to such a configuration, the striking force switching button 81B is provided on the striking force display portion 81C, so that the striking force switching button 81B can be operated with the other hand while the handle portion 24 is held with one hand. Can do.

  According to such a configuration, since the microcomputer 82B always turns on the striking force display portion 81C when the amount of electricity is supplied to the power cord 9, there is no need to newly provide an energizing lamp, and the number of parts can be reduced. it can.

  According to such a configuration, the power from the power cord 9 is converted to DC power by the power circuit board 83 and supplied to the control circuit board 82. The power cord 9, the power circuit board 83, and the control circuit board 82 are arranged in this order. Therefore, they are arranged in the order in which power is supplied. Thereby, the wiring in the board | substrate accommodating part 25 can be suppressed to the minimum, and the space in the board | substrate accommodating part 25 can be utilized effectively. Furthermore, the substrate housing portion 25 can be reduced in size. Further, a heavy motor 3 or gear mechanism 4 is disposed on one end side of the handle portion 24 held by the operator, and a power circuit board 83 or a control circuit board 82 including elements having a relatively large mass on the other end side. Since the weight balance when the operator grips the handle portion 24 is good, the impact driver 1 can be realized that is less fatigued even during long-time work.

  According to such a configuration, since the microcomputer 82B is mounted on the control circuit board 82, the number of revolutions of the motor 3 can be controlled by the microcomputer 82B, and the strength of the striking force can be increased depending on the situation. Can be changed.

  According to such a configuration, since the motor 3 is accommodated in the body portion 23 and the power circuit board 83 is accommodated in the substrate accommodating portion 25, the power supply wiring supplied to the motor 3 is handled from the substrate accommodating portion 25 to the handle. The body 3 is connected to the motor 3 via the portion 24. Since the trigger 26 is provided in the handle portion 24 located in the middle between the substrate housing portion 25 and the body portion 23, each member is arranged in the housing 2 in the order in which power is supplied. The space in the housing 2 can be used effectively. Thereby, the impact driver 1 can be reduced in size.

  According to such a configuration, the choke coil 83 </ b> B and the first capacitor 83 </ b> C having a relatively large mass are accommodated on the handle portion 24 side in the handle portion 24, so that the weight when the operator grips the handle portion 24. It is possible to realize the impact driver 1 that has a good balance and is not easily fatigued even when working for a long time. Furthermore, the board | substrate accommodating part 25 can be reduced in size by utilizing the space in the handle | steering-wheel part 24 effectively.

  According to such a configuration, since the light 7 is held by the cover 21 and not by the metal hammer case 22, static noise is generated even when static noise or the like is generated in the hammer case 22. The light 7 is not affected. Thereby, damage of the light 7 by electrostatic noise can be prevented. Further, since the conventional hammer case 122 shown in FIGS. 16A to 16C is provided with the light support member 122A for supporting the light 7, electrostatic noise is concentrated on the portion. However, in this embodiment, as shown in FIGS. 8A to 8C, since the member for holding the light 7 in the hammer case 22 is no longer necessary, it is possible to prevent static noise from concentrating on this member. Thereby, the hammer case 22 can be made into a shape in which electrostatic noise is difficult to be charged.

  According to such a configuration, since the light 7 is sandwiched between the housing 2 and the cover 21, it is held more firmly.

  According to such a configuration, since the cover 21 is made of resin, it is possible to further improve the reliability of blocking static electricity noise to the light 7.

  According to such a configuration, the stator core 36 and the insulator 37 are fitted by the protrusions 36B and the protrusions 37A coming into contact with each other, so that the insulator 37 is fixed to the stator core 36 without making holes or the like in the stator core 36. can do. As a result, it is possible to prevent the magnetic flux from being reduced due to the holes in the stator core 36, so that the motor power can be improved even with a motor of the same size as the conventional one. Furthermore, this makes it possible to reduce the size of the motor 3, thereby reducing the size of the product.

  According to such a configuration, since the plurality of protrusions 37A are provided, the stator core 36 and the insulator 37 can be more firmly fixed.

  According to such a configuration, the convex portion 36 </ b> B is provided on the outer peripheral surface of the stator core 36, and the protruding portion 37 </ b> A is provided on the radially outer surface of the insulator 37, so that it is provided inside the stator core 36. Compared to the case, the internal space of the stator core 36 can be used effectively. As a result, the number of turns of the coil 33 can be increased, and the motor power can be improved. As a result, the size of the motor 3 can be reduced, and the impact driver 1 can be downsized.

  According to such a configuration, since the stator core 36 is supported by the first housing 2A and the second housing 2B by the convex portion 36B, the convex portion 36B is used as a member for fixing the insulator 37 to the stator core 36 and the stator core 36. Is used as a member for fixing to the housing 2. As a result, the stator core 36 can be fixed to the housing 2 without providing a new fixing member.

  According to such a configuration, since the insulating paper 38 is arranged over the entire inner peripheral surface of the slot 36a, the stator core 36 and the coil 33 can be reliably insulated by the insulating paper 38. Further, as compared with the case where the insulator core 37 and the coil 33 are insulated from each other by the insulator 37, the space in the slot 36a can be secured more widely when the insulation paper 38 is insulated, and the number of turns of the coil 33 can be increased. it can. As a result, the motor power can be improved and the size of the motor 3 can be reduced, so that the impact driver 1 can be reduced in size.

  According to such a configuration, since the air inlet 23a is formed only on the opposite side of the hammer 5 with respect to the motor 3, compared with the case where the air inlet 23a is formed at a plurality of locations, the collision of the airflow is reduced. No. Thereby, it becomes possible to take in outside air smoothly and to improve the cooling efficiency of the motor 3.

  According to such a configuration, since the switching element 39A is arranged between the air inlet 23a and the motor 3, the switching element 39A can be simultaneously cooled by the rotation of the cooling fan 35.

  According to such a configuration, since the longitudinal direction of the switching element 39A is parallel to the axial direction, the switching element 39A can be efficiently cooled.

  According to such a configuration, the intake port 23a and the switching element 39A are arranged so as to overlap each other when viewed in the axial direction, so that the switching element 39A can be efficiently cooled.

  The power tool of the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims. For example, a driver drill having a clutch, a hammer drill having a reciprocating striking mechanism, an oil pulse driver having a hydraulic striking mechanism, and the like may be used.

  In the present embodiment, the impact driver 1 is used as the power tool of the present invention. However, the present invention is limited to the impact driver as long as the power tool is mounted with a brushless motor and driven by an AC power source. It is not a thing.

  In the present embodiment, a planetary gear mechanism is used as the gear mechanism 4, but the present invention is not limited to this, and it is not always necessary to include a speed reduction mechanism.

  In the present embodiment, the front side of the light 7 is supported by the cover 21, but the present invention is not limited to this. As shown in FIG. 14, the cover 21 may have a light cover portion 221, and the light cover portion 221 may be interposed between the light 7 and the cover 21. Thereby, it is possible to further improve the reliability of blocking the static noise to the light 7.

  In the present embodiment, the rear side of the light 7 is supported by the housing 2, but the present invention is not limited to this. For example, as shown in FIG. 15, the light cover portion 221 and the rib 21 </ b> A may be sandwiched from above and below. Then, since the light 7 is separated from the housing 2 and the cover 21 is in contact with the housing 2, vibration during operation can be prevented from being transmitted to the light 7 through the housing 2. Thereby, damage to the light 7 can be prevented.

  In the present embodiment, four convex portions 36B of the stator core 36 are provided, but the present invention is not limited to this. Moreover, although the four protrusions 37A of the insulator 37 are provided, the present invention is not limited to this. For example, one protrusion may be provided, and two protrusions may be provided so as to sandwich the protrusion. Thereby, it can prevent that an insulator rotates with respect to a stator core.

  In the present embodiment, the protrusions 36B are provided on the outer peripheral surface of the stator core 36, and the protrusions 37A are provided on the outer peripheral surface of the insulator 37. However, the present invention is not limited to this. For example, the protrusions may be provided on the inner peripheral surface of the stator core, and the protrusions may be provided on the inner peripheral surface of the insulator. Further, a protrusion of the stator core may be provided on the contact surface between the insulator and the stator core, and a recess that fits into the protrusion may be provided on the insulator side. Even with such a configuration, since it is not necessary to make a hole in the stator core, a decrease in magnetic flux can be suppressed.

  In the present embodiment, the striking force level display portion 81C is used as the energizing lamp, but the present invention is not limited to this. For example, the mode display portion 81E may be used as an energizing lamp and lighted when power is supplied to the power cord 9. Further, the light 7 may be used as an energizing lamp.

  In the present embodiment, the cover 21 is made of resin, but is not limited thereto as long as it is an insulating material. For example, it may be made of rubber.

  In the present embodiment, the microcomputer 82B determines whether power is supplied to the power cord 9. However, the present invention is not limited to this. For example, the energization may be determined by an element provided on the power circuit board.

  In the present embodiment, the switching element 39A is arranged behind the motor, but the arrangement of the switching elements is not limited to this. For example, the power supply circuit board 83 may be provided, or the control circuit board 82 may be provided.

1. ・ Impact driver 2. ・ Housing 3. ・ Motor 4. ・ Gear mechanism 5. ・ Hammer 6. ・ Anvil 7. ・ Light 8. ・ Control unit 9. ・ Power cord 21. ・ Cover 21A ・ ・ Rib 22. · Hammer case 23 · · Body 23a · · Intake port 23b · · Exhaust port 24 · · Handle portion 25 · · Substrate housing portion 25A · · Protrusion portion 26 · · Trigger 31 · · Output shaft 32 · · Rotor 33 · · Coil 34 .. Stator 35 .. Cooling fan 36.. Stator core 36 A.. Teeth 36 B.. Protruding part 36 a ... Slot 37 A Insulator 37 A Projecting part 38 Insulating paper 39 Inverter circuit board 39 A Switching element 39B ・ ・ Hall element 52 ・ ・ Spring 81 ・ ・ Blowing force display panel 81A ・ ・ Light switch H 81B ·· Blowing force changeover switch 81C · · Blowing force level display section 81D · · Mode changeover switch 82 · · Control circuit board 82A · · Shock sensor 82B · · Microcomputer 83 · · Power supply circuit board 83A · · Diode bridge 83B・ ・ Choke coil 83C ・ ・ First capacitor 83D ・ ・ Second capacitor 221 ・ ・ Light cover

Claims (12)

A housing;
A motor having a stator and a rotor rotatable with respect to the stator, and housed in the housing;
An output unit driven by the motor,
The stator includes a stator core provided with a convex portion, an insulator provided with a projection capable of contacting the convex portion and connected to the stator core, and a coil fixed to the insulator. A power tool.   The power tool according to claim 1, wherein a plurality of the protrusions are provided.   The said stator core has a substantially cylindrical shape, the said convex part is provided in the outer peripheral surface of the said stator core, and the said projection part is provided in the outer peripheral surface of the said insulator, The Claim 1 or 2 characterized by the above-mentioned. Power tools. The housing is composed of a first housing and a second housing,
The electric tool according to claim 3, wherein the stator core is held in the housing by contacting the convex portion with the first housing and the second housing.   A plurality of slots extending in the axial direction are formed side by side in the circumferential direction on the inner surface of the stator core, and insulating paper is disposed on the entire inner peripheral surface of each of the slots. The power tool according to claim 3 or 4.   6. The electric tool according to claim 3, wherein the insulator is provided so as to be in contact with an axial end surface of the stator core. 6. A housing in which an air inlet and an air outlet are formed;
A motor housed in the housing and comprising an output shaft and a cooling fan fixed to the output shaft;
An electric power tool having an output unit driven by the output shaft, arranged alongside the motor in the housing, and a part of the output unit exposed to the outside,
The power tool according to claim 1, wherein the intake port is formed only on the opposite side of the output portion with respect to the motor, and the exhaust port is formed radially outward of the cooling fan. The motor is a brushless motor,
The power tool according to claim 7, wherein a plurality of switching elements for energizing the motor are arranged between the motor and the intake port.   The power tool according to claim 8, wherein the switching element is a substantially rectangular parallelepiped, and is arranged such that a longitudinal direction of the substantially rectangular parallelepiped is parallel to an axial direction of the output shaft.   10. The electric tool according to claim 8, wherein the switching element is disposed at a position overlapping the intake port when viewed in the axial direction of the output shaft.   The power tool according to any one of claims 7 to 10, wherein the cooling fan is a centrifugal fan. A housing;
A motor having a stator and a rotor rotatable with respect to the stator, and housed in the housing;
An output unit driven by the motor,
The stator includes a stator core having an engaging portion, an insulator provided with an engaged portion engageable with the engaging portion and connected to the stator core, and a coil fixed to the insulator. An electric tool characterized by

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