JP5488919B2 - Motor and electric tool - Google Patents

Description

  The present invention relates to a motor and a power tool equipped with the motor.

  A conventional disk motor includes an output shaft, a rotor having a commutator and a coil connected to the commutator, and a rotor fixed to the output shaft, and a stator including a plurality of magnets provided at positions facing the coil. And a pair of brushes that supply power to the rotor by contacting the commutator.

  The rotor has a substantially disk shape, and is composed of a substrate on which a commutator is provided on the surface that is a surface orthogonal to the output shaft, and coils are printed on the front and back surfaces. (For example, refer to Patent Documents 1 and 2).

JP 2003-032977 A Japanese Patent Laid-Open No. 2003-180054

  However, in conventional disk motors, interference noise and interference radio waves are generated by the contact between the brush and the commutator. Also, in a disk motor, power is supplied to a commutator disposed on a disk-shaped rotor, so that one brush and another brush are spaced apart from each other by a predetermined distance at a position opposite to the output shaft by 180 °. Provided. Thereby, compared with a normal motor, since the distance between the brushes is separated, the sliding contact speed between the commutator and the brush is increased. As a result, problems such as radio interference and interference noise have become more prominent.

  Accordingly, the present invention is intended to provide a motor that reduces interference noise and interference radio waves and extends the life of the brush, and an electric tool equipped with the motor.

The present invention includes a housing, a stator fixed to the housing, an output shaft housed in the housing, a coil portion fixed to the output shaft, and a commutator connected to the coil portion. A substantially disc-shaped commutator portion fixed to a shaft, an armature that can rotate in both directions around the output shaft with respect to the stator, and a brush that can contact the commutator, A brush holder that is supported by the housing to be rotatable about the output shaft with respect to the stator and holds the brush, and the commutator portion is fixed coaxially to the output shaft, The housing has a front surface and a back surface that are orthogonal to the axial direction of the output shaft, the coil portion is provided on one of the front surface and the back surface, and the commutator is provided on the other . First housing The brush holder is rotatably held by the second housing member, and one end of the output shaft is rotatably supported by the first housing member. The other end of the output shaft is rotatably supported by a second housing member, the housing further includes a cover supported by the second housing member, and the brush holder is disposed in the output shaft direction by the cover. There is provided a motor characterized in that movement is restricted .

  According to such a configuration, since the brush holder can rotate around the output shaft with respect to the stator, even if the amateur rotates in any direction, the brush holder can be appropriately rotated by rotating the brush holder with respect to the stator. The brush shift amount can be obtained. Thereby, it is possible to extend the life of the carbon brush and reduce interference noise and interference radio waves. Further, since heat generation due to rectification between the commutator and the brush is reduced, durability of the commutator can be enhanced. Furthermore, since the commutator portion is formed in a substantially disc shape, a motor with a reduced thickness in the output shaft direction can be realized.

  Moreover, it is preferable that the said coil part is coaxially fixed with respect to the said output shaft, and the coil is fixed to at least one of the surface which is a surface orthogonal to the axial direction of the said output shaft, and a back surface.

  According to such a configuration, since the coil portion is formed in a substantially disc shape, a motor with a reduced thickness in the output shaft direction can be realized.

  According to such a configuration, since the brush holder is rotatably held by the first housing, an appropriate brush shift amount can be obtained by rotating the brush holder with respect to the stator, and the carbon brush It is possible to extend the service life and reduce interference noise and interference radio waves. Further, since heat generation due to rectification between the commutator and the brush is reduced, durability of the commutator can be enhanced.

  The brush holder is rotatable between a first position and a second position rotated from the first position by a predetermined angle around the output shaft, and the brush holder is in the first position. It is preferable that when the arm is in the forward position, the armature rotates normally, and when the brush holder is in the second position, the armature reverses.

  According to such a configuration, the forward / reverse switching of the amateur can be switched by moving the brush holder between the first position and the second position. There is no need, and the number of parts and cost can be reduced.

  The predetermined angle is preferably smaller than 180 °.

  According to such a configuration, since the predetermined angle is smaller than 180 °, an appropriate brush shift amount can be obtained as compared with the case where the predetermined angle is 180 °. Thereby, it is possible to extend the life of the carbon brush and reduce interference noise and interference radio waves. Further, since heat generation due to rectification between the commutator and the brush is reduced, durability of the commutator can be enhanced.

    According to such a configuration, since the brush holder can rotate around the output shaft with respect to the stator, even if the amateur rotates in any direction, the brush holder can be appropriately rotated by rotating the brush holder with respect to the stator. It is possible to obtain a brush shift amount, and it is possible to extend the life of the carbon brush and reduce interference noise and radio interference. Further, since heat generation due to rectification between the commutator and the brush is reduced, durability of the commutator can be enhanced. Furthermore, since the coil portion is formed in a substantially disk shape, a motor with a reduced thickness in the output shaft direction can be realized.

  In another aspect of the present invention, an electric tool equipped with a motor having the above-described characteristics is provided.

  According to such a configuration, it is possible to realize a power tool in which the brush has a long life and interference noise and electromagnetic interference are reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the motor which reduces interference noise and interference electromagnetic wave, and extends the lifetime of a brush, and the electric tool carrying the motor can be provided.

The top view when the motor of the electric tool which concerns on the 1st Embodiment of this invention rotates right The top view when the motor of the electric tool which concerns on the 1st Embodiment of this invention rotates counterclockwise Sectional drawing along II-II of FIG. 1A of the electric tool which concerns on the 1st Embodiment of this invention The top view when the motor of the electric tool which concerns on the modification of the 1st Embodiment of this invention rotates right. Partial sectional view along IIIB-IIIB of FIG. 3A of the electric power tool according to the modification of the first embodiment of the present invention. The top view when the motor of the electric tool which concerns on the 2nd Embodiment of this invention rotates rightward The top view when the motor of the electric tool which concerns on the 2nd Embodiment of this invention rotates counterclockwise The top view when the motor of the electric tool which concerns on the 3rd Embodiment of this invention rotates rightward The top view when the motor of the electric tool which concerns on the 3rd Embodiment of this invention rotates counterclockwise The elements on larger scale of the brush holder of the electric tool which concerns on the 3rd Embodiment of this invention Sectional drawing along VI-VI of FIG. 5A of the electric tool which concerns on the 3rd Embodiment of this invention

  Hereinafter, a first embodiment of an electric drill 1 which is an example of an electric tool of the present invention will be described with reference to FIGS. 1A, 1B and 2. The electric drill 1 is mainly composed of a housing 2, a disk motor 3, a brush support portion 4, a tip tool holding portion 5, and a power cord 6. In FIG. 2, the direction in which the tip tool holding portion 5 is disposed with respect to the disk motor 3 is defined as “down”, and the opposite is defined as “up”. The extending direction of the power cord 6 is defined as rear and the reverse is defined as front.

  The housing 2 includes an upper housing member 21, a lower housing member 22, and a handle housing 23. The upper housing member 21 supports the disk motor 3 so as to be rotatable from above, and the lower housing member 22 supports the disk motor 3 so as to be rotatable from below. That is, the upper housing member 21 and the lower housing member 22 cooperate to support the disk motor 3 in a rotatable manner. As shown in FIGS. 1A and 1B, the upper housing member 21 and the lower housing member 22 are fixed to each other by four screws 2A. The handle housing 23 extends rearward from the upper housing member 21 and the lower housing member 22, and is connected to the upper housing member 21 by two screws 2B. A power cord 6 is connected to the rear portion of the handle housing 23. The handle housing 23 is provided with a trigger 24, and the trigger 24 is connected to a trigger switch 25 housed inside the handle housing 23. The trigger switch 25 is connected to the power cord 6. The operator can supply power to the disk motor 3 by pulling the trigger 24. The handle housing 23 is provided with a forward / reverse selector switch 26. When the forward / reverse selector switch 26 is switched to "R" as shown in FIG. 1A, the disk motor 3 rotates clockwise (clockwise in FIG. 1A). As shown in FIG. 1B, when the forward / reverse selector switch 26 is switched to “L”, the disk motor 3 rotates counterclockwise (counterclockwise in FIG. 1B).

  The disk motor 3 includes an output shaft 31, a rotor 32, a stator 33, and a brush 34. The output shaft 31 extends in the vertical direction and is rotatably supported by the upper housing member 21 at the upper end portion and rotatably supported by the lower housing member 22 at the lower portion. A tip tool holding portion 5 is attached to the lower end portion of the output shaft 31. The output shaft 31 and the rotor 32 constitute an armature of the present invention.

  The rotor 32 includes a commutator substrate 35, a coil portion 36, and a spacer 37. The commutator substrate 35 has a substantially disc shape and is coaxially fixed to the output shaft 31 so that the axis of the commutator substrate 35 and the axis of the output shaft 31 coincide with each other. A commutator (not shown) is provided on the upper surface of the surface orthogonal to the axial direction of the output shaft 31 of the commutator substrate 35. The coil portion 36 has a substantially disc shape, and is coaxially fixed to the output shaft 31 so that the axis of the coil portion and the axis of the output shaft 31 coincide with each other. The coil portion 36 is configured by laminating a plurality of substantially disk-shaped coil substrates and molding them with resin. Coils (not shown) connected to a commutator (not shown) are provided on the upper and lower surfaces of the surface orthogonal to the axial direction of the output shaft 31 of the coil substrate. The spacer 37 is inserted between the lower surface of the commutator substrate 35 and the upper surface of the coil portion 36 and is used to increase the strength of the rotor 32.

  The stator 33 includes a plurality of magnets 38 and a yoke 39. The plurality of magnets 38 are supported by the lower housing member 22 and are provided at positions facing the coil portion 36. The yoke 39 is supported by the upper housing member 21 and the lower housing member 22 and is disposed around the magnet 38 in order to strengthen the magnetic force of the magnet 38. More specifically, the yoke 39 supported by the upper housing member 21 is provided at a position facing the magnet 38 with the coil portion 36 interposed therebetween, and the yoke 39 supported by the lower housing member 22 surrounds the magnet 38. Are arranged as follows. Magnetic flux generated from the magnet 38 passes through the coil portion 36 in the vertical direction. At this time, when current is supplied from the brush 34 to the coil unit 36 via a commutator (not shown), torque is generated in the coil unit 36 in the circumferential direction around the output shaft 31, and the output shaft 31. Rotates.

  The brush 34 is supported by the brush support portion 4 and is biased downward by a spring 43 described later on the upper surface of the brush 34 so that the lower surface of the brush 34 abuts on a commutator (not shown) on the commutator substrate 35. Has been.

  The brush support portion 4 includes a brush holder 41, a cover 42, a spring 43, and a lid 44. The brush holder 41 is disposed so as to cover a part of the upper surface of the upper housing member 21, and is configured to be rotatable about the output shaft 31 with respect to the upper housing member 21. More specifically, the brush holder 41 is located between a right rotation position (position shown in FIG. 1A) and a left rotation position (position shown in FIG. 1B and rotated in a clockwise direction by a predetermined counter angle from FIG. 1A). It can be rotated. In the brush holder 41, a pair of through holes 41a are formed so as to penetrate vertically to the position of the counter electrode with the output shaft 31 as a center. Inside the through hole 41a, a brush 34 and a spring 43 are provided. The upper part is closed by the lid 44 accommodated. On the upper surface of the brush holder 41, a knob 41A having a substantially I-shaped cross section orthogonal to the output shaft 31 is provided so as to protrude upward, and a triangular arrow 41B is provided at one end of the approximately I-shape. .

  The cover 42 has a thin cylindrical shape, and is fixed to the upper housing member 21 with screws 42 </ b> A so as to cover the periphery of the brush holder 41. As a result, the brush holder 41 cannot move up and down and can rotate with respect to the upper housing member 21. The cover 42 is provided with “R” and “L” marks. By aligning the arrow 41B of the knob 41A with the “R” position, the brush holder 41 is rotated to the right (FIG. 1A). By matching with the position of “L”, the brush holder 41 becomes the left rotation position (FIG. 1B). Here, when the brush holder 41 is in the clockwise rotation position (FIG. 1A), the brush 34 is in a state where the brush is shifted by an angle θ with respect to the center line C. The brush shift is to rotate the brush 34 about the output shaft 31 by a predetermined angle (angle θ in the present embodiment) by the amount of deviation of magnetic flux in order to reduce interference noise and interference radio waves. The center line C can be determined by an experiment each time depending on the strength of the magnetic force of the magnet and the interval between the magnets. In this embodiment, when the brush holder 41 is in the right rotation position (FIG. 1A), the brush 34 is brush-shifted by the angle θ with respect to the center line C, and the brush holder 41 is in the left rotation position ( Also in FIG. 1B, the brush 34 is in a state where the brush 34 is shifted by an angle θ in the opposite direction to the case of the clockwise rotation position with respect to the center line C. Thus, even in the case of the bi-directionally rotating disk motor 3 as in the present embodiment, by rotating the brush holder 41, the disk motor 3 is moved to a position (brush shifted position) corresponding to the rotating direction of each disk motor 3. The brush 34 can be arranged. As a result, it is possible to obtain an effect of reducing interference noise and interference radio waves in any rotation direction.

  The spring 43 is in contact with the brush 34 at the lower end and is in contact with the lid 44 at the upper end, and urges the brush 34 toward the commutator (not shown). Thus, even when the brush 34 is worn, the brush 34 is always in contact with a commutator (not shown).

  The tip tool holding portion 5 is detachably attachable to a tip tool (not shown), and is fixed to the lower end portion of the output shaft 31 so as to be coaxially rotatable. The tip tool holding unit 5 has a chuck 51, and holds a tip tool (not shown) by the chuck 51. The power cord 6 supplies power to the electric drill 1 by being connected to a power source (not shown).

  Next, the operation of the electric drill 1 will be described. The operator rotates the disk motor 3 by connecting the power cord 6 to a power source (not shown) and pulling the trigger 24. At this time, in the state shown in FIG. 1A (the forward / reverse selector switch 26 is on the “R” side and the brush holder 41 is in the clockwise rotation position), the disk motor 3 is in the right direction (clockwise direction in FIG. 1A). The rotational force is transmitted to the tip tool holder 5 on the same axis. Thereby, a tip tool (not shown) held by the chuck 51 also rotates. At this time, since the brush 34 is in a state of being brush-shifted by the angle θ, interference noise and interference radio waves are reduced. The electric drill 1 is stopped by turning off the trigger 24.

  Next, when the operator wants to switch the rotation direction of the electric drill 1, the forward / reverse selector switch 26 is switched to the “L” side (FIG. 1B). At this time, the brush holder 41 is also switched to the left rotation position. Thereby, the brush holder 41 rotates in the left direction (counterclockwise direction in FIG. 1B). Further, since the brush holder 41 is in the counterclockwise rotation position, even when the disk motor 3 rotates in the left direction, the brush 34 is in a state of being brush-shifted by the angle θ. Reduced.

  According to such a configuration, since the brush holder 41 can rotate about the output shaft 31 with respect to the stator 33, the brush holder 41 is not fixed to the stator 33 regardless of the direction of rotation of the disk motor 3. It is possible to obtain an appropriate brush shift amount by rotating with respect to. Thereby, it is possible to extend the life of the brush 34 and reduce interference noise and interference radio waves. Further, since heat generation due to rectification between the commutator (not shown) and the brush 34 is reduced, durability of the commutator (not shown) can be improved. Furthermore, since the commutator substrate 35 is formed in a substantially disc shape, the disk motor 3 with a reduced thickness in the direction of the output shaft 31 can be realized. Furthermore, since the coil portion 36 is formed in a substantially disc shape, the disk motor 3 with a reduced thickness in the direction of the output shaft 31 can be realized.

  According to such a configuration, since the coil portion 36 is formed in a substantially disc shape, the disk motor 3 with a reduced thickness in the direction of the output shaft 31 can be realized.

  According to such a configuration, since the brush holder 41 is rotatably held by the upper housing member 21, an appropriate brush shift amount can be obtained by rotating the brush holder 41 with respect to the stator 33. Further, it is possible to extend the life of the brush 34 and reduce interference noise and interference radio waves. Further, since heat generation due to rectification between the commutator (not shown) and the brush 34 is reduced, durability of the commutator (not shown) can be improved.

  Next, an electric drill 101 according to a modification of the first embodiment will be described with reference to FIGS. 3A and 3B. Components having the same configuration as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

As shown in FIG. 3A, the brush holder 141 is held so as to be rotatable about the output shaft 31 with respect to the upper housing member 21. The brush holder 141 includes a pair of brushes 34, and the brush 34 is located at the counter electrode with the output shaft 31 as the center. The brush holder 141 is provided with a knob 141 </ b> A, and the knob 141 </ b> A protrudes outward in the radial direction of the output shaft 31 from the cover 42 that covers the periphery of the brush holder 141. The upper housing member 21 is provided with “R” and “L” marks, and when the knob 141A is rotated to the “R” side (FIG. 3A), the brush 34 is brush-shifted by an angle θ during the clockwise rotation. It will be in the state.
Similarly, when the knob 141A is rotated to the “L” side, the brush 34 is in a state of being brush-shifted by an angle θ during the left rotation. The operator can obtain the effect of brush shift in both directions of rotation of the disk motor 3 by matching the display of the forward / reverse selector switch 26 and the position of the knob 141A.

  Next, an electric drill 201 according to the second embodiment will be described with reference to FIGS. 4A and 4B. Components having the same configuration as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. In the electric drill 201 according to the second embodiment, the handle housing 23 is not provided with the forward / reverse switch 26, and the rotation direction of the disk motor 3 is switched by rotating the brush holder 241. This is different from the electric drill 1 of the embodiment.

  In the upper housing member 21, the brush holder 241 rotates around the output shaft 31 in the clockwise rotation position (position shown in FIG. 4A) and counterclockwise rotation position (position shown in FIG. 4B, and clockwise rotation by a predetermined angle from FIG. 4A). It is provided so as to be rotatable between the position and the position. The brush holder 241 includes a knob 241A whose section perpendicular to the vertical direction is substantially I-shaped, and a triangular arrow 241B provided at one end of the knob 241A.

  In the state shown in FIG. 4A, the brush 34 is in a state where the brush is shifted by an angle θ, and the disk motor 3 rotates in the right direction (clockwise direction in FIG. 4A). In the state shown in FIG. 4B, the brush 34 is in a state where the brush is shifted by an angle θ, and the disk motor 3 rotates in the left direction (counterclockwise direction in FIG. 4B). In the state shown in FIG. 4B, the position of the brush holder 241 (brush 34) is inverted by 180 ° as compared with the state of FIG. 1B of the first embodiment. In other words, since the polarity of the brush 34 is reversed, the disk motor 3 can be rotated in the reverse direction without a member corresponding to the forward / reverse selector switch 26 of the first embodiment.

  With such a configuration, the rotation direction of the disk motor 3 can be switched only by the operation of rotating the brush holder 241, and at the same time, the effect of brush shift can be obtained. Furthermore, since a member corresponding to the forward / reverse selector switch 26 of the first embodiment is not necessary, the number of parts can be reduced, and the manufacturing cost can be suppressed. Further, since there is only one place to be switched when the disk motor 3 is reversely rotated (only the rotation of the brush holder 41), only the forward / reverse selector switch 26 of the first embodiment is switched and the brush holder 41 is not switched. Can be prevented.

  According to such a configuration, the angle between the right rotation position and the left rotation position of the brush holder 241 is smaller than a predetermined angle of 180 °, so that an appropriate brush shift amount can be obtained as compared with the case of 180 °. Become. Thereby, it is possible to extend the life of the brush 34 and reduce interference noise and interference radio waves. Further, since heat generation due to rectification between the commutator (not shown) and the brush 34 is reduced, durability of the commutator (not shown) can be improved.

  Next, the electric drill 301 which concerns on 3rd Embodiment is demonstrated with reference to FIG. 5A, 5B, 5C, and 6. FIG. Components having the same configuration as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the upper housing member 21, the brush holder 341 rotates around the output shaft 31 in the clockwise rotation position (position shown in FIG. 5A) and counterclockwise rotation position (position shown in FIG. 5B, and rotates clockwise by a predetermined angle from FIG. 5A. It is provided so as to be rotatable between the position and the position. The brush holder 341 has a knob 341A having a substantially I-shaped cross section perpendicular to the vertical direction, a triangular arrow 341B provided at one end of the knob 341A, and a protrusion protruding from the outer peripheral edge by a length L outward in the radial direction. 341C (FIG. 5C). The protrusion 341C is located away from the center line C when the brush holder 341 is in the right rotation position (FIG. 5A), but is center line C when the brush holder 341 is in the left rotation position (FIG. 5B). Located on the top.

  As shown in FIGS. 5 and 6, a sensor 327 that detects the position of the brush holder 341 and a controller 328 that receives a signal from the sensor 327 and controls the rotation direction of the disk motor 3 are provided in the handle housing 23. It has been. The sensor 327 has a detection unit 327A. When the detection unit 327A protrudes from the sensor 327 (the state shown in FIG. 5A), the controller 328 moves the disk motor 3 to the right (the clockwise direction in FIG. 5A). The controller 328 controls the disk motor 3 to the left (counterclockwise direction in FIG. 5B) when the detection unit 327A is pushed into the sensor 327 by the protrusion 341C (the state shown in FIG. 5B). ) Is controlled to rotate.

  With such a configuration, the rotation direction of the disk motor 3 can be switched only by the operation of rotating the brush holder 341, and at the same time, the effect of brush shifting can be obtained. Further, since there is only one place to be switched when the disk motor 3 rotates in reverse (only the rotation of the brush holder 341), only the forward / reverse switch 26 in the first embodiment is switched and the brush holder 41 is not switched. Can be prevented.

  The motor and the electric tool according to the present invention are not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the invention described in the claims, for example.

  In the electric drill 1 of the first embodiment, if the trigger 24 is accidentally pulled when the forward / reverse selector switch 26 is “R” and the brush holder 41 is “L”, the brush 34 is properly Since the position is not a brush-shifted position, generation of interference radio waves and interference noise becomes more severe. In order to prevent such a situation, an interlock circuit is added and the forward / reverse selector switch 26 is “R” and the brush holder 41 is “R” or the forward / reverse selector switch 26 is “L” and the brush If the holder 41 is not “L”, the disc motor 3 may be configured not to operate even when the trigger 24 is pulled.

  In the electric drill 301 of the third embodiment, the position of the brush holder 341 is detected by the sensor 327, but the type of sensor is not limited to this example. For example, a proximity sensor or a laser sensor may be used.

  In the rotor 32 of the present invention, the spacer 37 is provided between the commutator substrate 35 and the coil portion 36, but the spacer 37 may not be provided when the strength of the coil portion 36 is sufficient. Thereby, the rotor 32 is reduced in weight and the efficiency of the disk motor 3 is increased.

  In the present invention, power is supplied to the electric drills 1, 101, 201, 301 by the power cable 6, but a battery or the like may be mounted, for example.

  Although the present invention has been described by taking the electric drills 1, 101, 201, and 301 capable of bidirectional rotation as examples, the present invention is not limited thereto. For example, if it is an electric tool provided with a motor, it is applicable also to electric tools, such as electric hammers other than an electric drill, an electric hammer drill, an electric grinder, and an electric circular saw.

DESCRIPTION OF SYMBOLS 1, 101, 201, 301 ... Electric drill 2. Housing 3. Disk motor 4. Brush support part 5. Tip tool holding part 6. Power cord 21. Upper housing member 22. Lower housing member 23. Handle housing 24. Trigger 26. Forward / reverse selector switch 31. Output shaft 32. Rotor 33. Stator 34. Brush 35. Commutator board 36. Coil portion 37. Spacer 38.・ Magnet 39 ・ ・ Yoke 41, 141, 241 and 341 ・ ・ Brush holder 41A, 141A ・ ・ Knob 42,242,342 ・ ・ Cover 327 ・ ・ Sensor 327A ・ Detection unit 328 ・ ・ Controller 341C ・ ・ Protrusion

Claims (5)

A housing;
A stator fixed to the housing;
An output shaft housed in the housing; a coil portion fixed to the output shaft; and a substantially disc-shaped commutator portion including a commutator connected to the coil portion and fixed to the output shaft. An armature capable of rotating in both directions around the output shaft with respect to the stator;
A brush capable of contacting the commutator;
A brush holder that is supported by the housing to be rotatable about the output shaft with respect to the stator and holds the brush;
The commutator portion is fixed coaxially to the output shaft, has a front surface and a back surface that are orthogonal to the axial direction of the output shaft, and the coil portion is provided on either the front surface or the back surface. The other side is provided with the commutator,
The housing is composed of a first housing member and a second housing member, and the brush holder is rotatably held by the second housing member,
One end of the output shaft is rotatably supported by the first housing member, the other end of the output shaft is rotatably supported by the second housing member, and the housing is further supported by the second housing member. The motor is characterized in that the brush holder is restricted from moving in the output shaft direction by the cover .   The coil portion is fixed coaxially to the output shaft, and the coil is fixed to at least one of a front surface and a back surface that are surfaces orthogonal to the axial direction of the output shaft. The motor described. The brush holder is rotatable between a first position and a second position rotated from the first position by a predetermined angle around the output shaft, and the brush holder is in the first position. 3. The motor according to claim 1, wherein the armature rotates forward and the armature rotates reversely when the brush holder is in the second position. 4. The motor according to claim 3 , wherein the predetermined angle is smaller than 180 °. An electric tool equipped with the motor according to any one of claims 1 to 4 .

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