Electrically-driven work machine

Abstract

To reduce the size and weight of a sensor substrate for an electrically-driven work machine.SOLUTION: An electrically-driven work machine comprises: a motor having a rotor that rotates about a rotational shaft and a stator arranged around the rotor; and a sensor substrate having a rotational sensor that detects a rotation of the rotor and a plate supporting the rotational sensor. The stator includes: a stator core arranged around the rotor; an insulator fixed to the stator core; and a plurality of coils fixed to the insulator and arranged in a circumferential direction at intervals. The plate includes: an arc part that is arranged in a part of a circumference of the rotational shaft and includes an opposing surface that is opposite an axial end surface of the rotor; and at least two arm parts projecting radially outwardly from the arc part and fixed to the insulator. The rotational sensor is arranged on the opposing surface.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The technology disclosed in this specification relates to an electric operating machine. [Background technology]

[0002] 2. Description of the Related Art In the technical field relating to electric operating machines, an electric operating machine including a motor and a sensor board, as disclosed in Patent Document 1, is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-012822 Summary of the Invention [Problem to be solved by the invention]

[0004] When an electric working machine becomes large, it may become difficult for a worker who uses the electric working machine to use the electric working machine smoothly. Therefore, there is a demand for electric working machines to be made smaller and lighter. When an electric working machine includes a sensor board, the smaller and lighter sensor board contributes to the smaller and lighter electric working machine.

[0005] The technology disclosed in this specification aims to reduce the size and weight of a sensor board for an electric work machine. [Means for solving the problem]

[0006] This specification discloses an electric working machine. The electric working machine may include a motor having a rotor rotating around a rotation axis and a stator arranged around the rotor, a rotation sensor that detects rotation of the rotor, and a sensor board having a plate that supports the rotation sensor. The stator may have a stator core arranged around the rotor, an insulator fixed to the stator core, and a plurality of coils fixed to the insulator and arranged at intervals in the circumferential direction. The plate may have an arc portion arranged on a part of the circumference of the rotation axis and having an opposing surface that faces an end face of the rotor in the axial direction, and at least two arm portions that protrude radially outward from the arc portion and are fixed to the insulator. The rotation sensor may be arranged on the opposing surface. Effect of the Invention

[0007] According to the technology disclosed in this specification, the sensor board of an electric work machine can be made smaller and lighter. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a side view showing an electric operating machine according to a first embodiment. [Diagram 2] FIG. 2 is an exploded perspective view showing the motor assembly according to the first embodiment, as viewed from the front. [Diagram 3] FIG. 3 is a rear perspective view showing the stator and the sensor board according to the first embodiment. [Figure 4] FIG. 4 is a view of the stator and the sensor board according to the first embodiment as viewed from the front. [Diagram 5] FIG. 5 is a view of the stator according to the first embodiment as viewed from the front. [Figure 6] FIG. 6 is a rear view of the stator and the sensor board according to the first embodiment. [Figure 7] FIG. 7 is a view of the stator and the sensor board according to the first embodiment as viewed from the left. [Figure 8] FIG. 8 is a cross-sectional view showing the stator and the sensor board according to the first embodiment. [Figure 9] FIG. 9 is an exploded perspective view showing the stator and the sensor board according to the first embodiment, as viewed from the front. [Figure 10] FIG. 10 is a view of the stator and the sensor board according to the second embodiment as viewed from the front. [Figure 11] FIG. 11 is a view of the stator according to the second embodiment as viewed from the front. [Figure 12] FIG. 12 is a view of the stator and the sensor board according to the second embodiment as viewed from the left. [Figure 13] FIG. 13 is a cross-sectional view showing a stator and a sensor board according to the second embodiment. [Figure 14] FIG. 14 is a view of the stator and the sensor board according to the third embodiment as viewed from the front. [Figure 15] FIG. 15 is a view of the stator according to the third embodiment as viewed from the front. [Figure 16] FIG. 16 is a view of the stator and the sensor board according to the third embodiment as viewed from the left. [Figure 17] FIG. 17 is a cross-sectional view showing a stator and a sensor board according to the third embodiment. [Figure 18] FIG. 18 is an exploded perspective view showing a stator and a sensor board according to the third embodiment, as viewed from the front. [Figure 19] FIG. 19 is a cross-sectional view showing a stator and a sensor board according to the third embodiment. [Figure 20] FIG. 20 is a view of the stator and the sensor board according to the fourth embodiment as viewed from the front. [Figure 21] FIG. 21 is a view of the stator according to the fourth embodiment as viewed from the front. [Figure 22] FIG. 22 is a view of the stator and the sensor board according to the fourth embodiment as viewed from the left. [Figure 23] FIG. 23 is a cross-sectional view showing a stator and a sensor substrate according to the fourth embodiment. [Figure 24] FIG. 24 is a view of the stator and the sensor board according to the fifth embodiment as viewed from the front. [Diagram 25] FIG. 25 is a view of the stator and the sensor board according to the fifth embodiment as viewed from the left. [Figure 26] FIG. 26 is a cross-sectional view showing a stator and a sensor board according to the fifth embodiment. [Figure 27] FIG. 27 is a view of the stator and the sensor board according to the sixth embodiment as viewed from the front. [Figure 28] FIG. 28 is a view of the stator and the sensor board according to the sixth embodiment as viewed from the left. [Figure 29] FIG. 29 is a cross-sectional view showing a stator and a sensor board according to the sixth embodiment. [Diagram 30] FIG. 30 is a view of the stator and the sensor board according to the seventh embodiment as viewed from the front. [Diagram 31] FIG. 31 is a view of the stator and the sensor board according to the seventh embodiment viewed from the left. [Diagram 32] FIG. 32 is a cross-sectional view showing a stator and a sensor substrate according to the seventh embodiment. [Diagram 33] FIG. 33 is a view of the stator and the sensor board according to the eighth embodiment as viewed from the front. [Diagram 34] FIG. 34 is a view of the stator and the sensor board according to the eighth embodiment as viewed from the left. [Diagram 35] FIG. 35 is a cross-sectional view showing a stator and a sensor board according to the eighth embodiment. [Diagram 36] FIG. 36 is a view of the stator and the sensor board according to the ninth embodiment as viewed from the front. [Figure 37] FIG. 37 is a diagram for explaining the relationship between the opposing surface and the reverse surface and the front end of the coil according to the tenth embodiment. [Figure 38] FIG. 38 is a view of the stator and the sensor board according to the eleventh embodiment as viewed from the front. [Figure 39] FIG. 39 is an exploded perspective view showing the stator and the sensor board according to the eleventh embodiment, as viewed from the front. [Diagram 40]FIG. 40 is a cross-sectional view showing a stator and a sensor board according to the eleventh embodiment. [Diagram 41] FIG. 41 is a perspective view showing a portion of the sensor substrate according to the eleventh embodiment that is covered with a covering portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In one or more embodiments, the electric operating machine may include a motor having a rotor rotating about a rotation axis and a stator arranged around the rotor, a rotation sensor that detects rotation of the rotor, and a sensor board having a plate supporting the rotation sensor. The stator may have a stator core arranged around the rotor, an insulator fixed to the stator core, and a plurality of coils fixed to the insulator and arranged at intervals in the circumferential direction. The plate may have an arc portion arranged on a part of the circumference of the rotation axis and having an opposing surface that faces an end face of the rotor in the axial direction, and at least two arm portions that protrude radially outward from the arc portion and are fixed to the insulator. The rotation sensor may be arranged on the opposing surface.

[0010] In the above configuration, part of the plate of the sensor board is an arc portion, so the sensor board is made smaller and lighter. Part of the plate fixed to the insulator is an arm portion, so the sensor board is made smaller and lighter. By making the sensor board smaller and lighter, the motor assembly including the motor and the sensor board is made smaller and lighter. This makes the electric work machine smaller and lighter. Also, a large number of plates are manufactured from a single rectangular printed wiring board (PWB: Printed Wiring Board).

[0011] In one or more embodiments, the arc portion may be disposed radially inward from the coil.

[0012] In the above configuration, the motor assembly is made smaller in size in the radial direction.

[0013] In one or more embodiments, an end of the radially outer arm may be disposed radially outward from the coil. The end of the arm may be fixed to the insulator.

[0014] In the above configuration, the end of the arm portion is fixed to the insulator, thereby fixing the sensor board to the insulator.

[0015] In one or more embodiments, the opposing surface may be axially disposed closer to the center of the coil than to one end of the coil.

[0016] In the above configuration, at least a portion of the arc portion fits radially inside the coil, thereby reducing the size of the motor assembly in the axial direction.

[0017] In one or more embodiments, the arc portion may have a reverse surface that faces in an opposite direction to the opposing surface, and the reverse surface may be axially disposed closer to a center of the coil than one end of the coil.

[0018] In the above configuration, the entire arc portion fits radially inside the coil, making the motor assembly smaller in size in the axial direction.

[0019] In one or more embodiments, the plates may be parallel plates.

[0020] In the above configuration, the plate is manufactured from a printed wiring board (PWB).

[0021] In one or more embodiments, the arm portion may be disposed between a pair of adjacent coils.

[0022] In the above configuration, even if the plate is a parallel flat plate, at least a part of the arcuate portion enters the radially inner side of the coil.

[0023] In one or more embodiments, the arm portion may include a first arm portion and a second arm portion, the first arm portion protruding radially outward from one end of the circumferential arc portion, and the second arm portion protruding radially outward from the other end of the circumferential arc portion.

[0024] In the above configuration, bending and vibration of the end of the circumferential arc portion is suppressed.

[0025] In one or more embodiments, the plate may include a bridge portion connecting a radially outer end of the first arm portion and an end of the second arm portion.

[0026] In the above configuration, the strength of the plate is improved.

[0027] In one or more embodiments, the bridge portion may be an arc disposed partially around the axis of rotation.

[0028] With the above configuration, an increase in size of the motor assembly in the radial direction is suppressed.

[0029] In one or more embodiments, the electric operating machine may include a controller that controls a drive current supplied to the coil based on a detection signal of the rotation sensor, and a signal line that connects the rotation sensor and the controller. The signal line may be supported by the bridge portion.

[0030] In the above configuration, the signal line is supported by the bridge portion of the plate.

[0031] In one or more embodiments, the arm portion may include a third arm portion. The third arm portion may protrude radially outward from a central portion of the circumferential arc portion.

[0032] In the above configuration, the first arm portion, the second arm portion, and the third arm portion are each fixed to the insulator, so that the sensor board is sufficiently fixed to the insulator.

[0033] In one or more embodiments, the electric operating machine may include a controller that controls a drive current supplied to the coil based on a detection signal of the rotation sensor, and a signal line that connects the rotation sensor and the controller. The signal line may be supported by the third arm portion.

[0034] In the above configuration, the signal line is supported by the third arm portion of the plate.

[0035] In one or more embodiments, the electric operating machine may include a power supply terminal through which a drive current flows. The third arm portion may be disposed so as to overlap the power supply terminal in a plane perpendicular to the rotation axis.

[0036] With the above configuration, an increase in size of the motor assembly in the radial direction is suppressed.

[0037] In one or more embodiments, at least one of the first arm portion, the second arm portion, and the third arm portion may be secured to the insulator by a screw.

[0038] In the above configuration, the sensor board can be easily replaced with a new sensor board by removing the screws.

[0039] In one or more embodiments, the plate may include a cover portion connecting a radially outer end of the first arm portion, an end of the second arm portion, and an end of the third arm portion.

[0040] In the above configuration, the strength of the plate is improved.

[0041] In one or more embodiments, the electric operating machine may include a controller that controls a drive current supplied to the coil based on a detection signal of the rotation sensor, and a signal line that connects the rotation sensor and the controller. The signal line may be supported by the cover portion.

[0042] In the above configuration, the signal line is supported by the cover portion of the plate.

[0043] In one or more embodiments, the electric operating machine may include a power supply terminal through which a drive current flows. The cover portion may be disposed so as to overlap the power supply terminal in a plane perpendicular to the rotation axis.

[0044] With the above configuration, an increase in size of the motor assembly in the radial direction is suppressed.

[0045] In one or more embodiments, the electric operating machine may include a support member fixed to the insulator. The at least two arm portions may be fixed to the insulator via the support member.

[0046] In the above-described configuration, the plate is fixed to the insulator via the support member. Even if the plate is a parallel plate, the shape of the support member can be adjusted so that the plate and the insulator are properly fixed to each other via the support member.

[0047] In one or more embodiments, the support member may have a support arc portion fixed to the insulator by a first screw, and a screw boss portion disposed radially inward from the support arc portion and to which the arm portion is fixed by a second screw. In the axial direction, an end face of the screw boss portion facing the same direction as the opposing surface may be disposed closer to the center of the coil than an end face of the stator core facing the opposite direction to the opposing surface.

[0048] In the above configuration, the plate is stably fixed to the insulator via the support member. Since the screw boss portion is disposed radially inward from the support arc portion, the length of the screw boss portion is not restricted. When the plate is disposed at a position closer to the center of the coil than one end of the coil and the plate is fixed to the insulator by the second screw, if the second screw is long, the tip of the second screw may hit the end face of the stator core, so that it may be necessary to shorten the second screw. If the second screw is short, the fixing of the plate and the insulator may become unstable. In the present embodiment, since the length of the screw boss portion is not restricted, a long second screw can be used even when the plate is disposed at a position closer to the center of the coil than one end of the coil. Therefore, the plate is stably fixed to the insulator via the support member.

[0049] Hereinafter, an embodiment according to the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiment. The components of the embodiments described below can be appropriately combined. In addition, some components may not be used.

[0050] In the embodiment, the positional relationship of each part will be described using the terms "left," "right," "front," "rear," "upper," and "lower." These terms indicate relative positions or directions based on the center of the electric operating machine.

[0051] The electric operating machine has a motor. In the embodiments, a direction parallel to a rotation axis AX of the motor is appropriately referred to as an axial direction. A radial direction of the rotation axis AX of the motor is appropriately referred to as a radial direction. A direction going around the rotation axis AX of the motor is appropriately referred to as a circumferential direction or a rotation direction.

[0052] A position or direction on one side in the axial direction is appropriately referred to as "one axial side," and a position or direction on the other side in the axial direction is appropriately referred to as "the other axial side." In the embodiment, the rotation axis AX of the motor extends in the front-rear direction. The axial direction and the front-rear direction are parallel. The one axial side is the front side, and the other axial side is the rear side.

[0053] In the radial direction, a position closer to or approaching the motor's rotation shaft AX is appropriately referred to as the radially inner side, and a position farther from or away from the motor's rotation shaft AX is appropriately referred to as the radially outer side.

[0054] A position or direction on one side in the circumferential direction will be referred to as “one circumferential side” as appropriate, and a position or direction on the other side in the circumferential direction will be referred to as “the other circumferential side” as appropriate. The one circumferential side is the forward rotation side, and the other circumferential side is the reverse rotation side.

[0055] [First embodiment] <Electric working equipment> A first embodiment will be described. Fig. 1 is a side view showing an electric working machine 1 according to this embodiment. In this embodiment, the electric working machine 1 is a vibration driver drill, which is a type of electric tool. As shown in Fig. 1, the electric working machine 1 includes a housing 2, a rear cover 3, a gear case 4, a battery mounting section 5, a motor assembly 6, a power transmission mechanism 7, a spindle 8, a controller 9, a trigger switch 10, a forward / reverse switching lever 11, a speed switching lever 12, a mode change ring 13, a change ring 14, and a light 15.

[0056] The housing 2 has a motor accommodating portion 16, a grip portion 17, and a controller accommodating portion 18. The housing 2 is made of synthetic resin.

[0057] The motor accommodating portion 16 accommodates at least a portion of the motor assembly 6. The motor accommodating portion 16 is cylindrical.

[0058] The grip portion 17 is held by an operator who uses the electric work machine 1. The grip portion 17 protrudes downward from the lower portion of the motor housing portion 16.

[0059] The controller accommodating portion 18 accommodates the controller 9. The controller accommodating portion 18 is connected to a lower end portion of the grip portion 17. The external dimensions of the controller accommodating portion 18 are larger than the external dimensions of the grip portion 17 in both the front-rear direction and the left-right direction.

[0060] The rear cover 3 is connected to the rear of the motor housing portion 16 so as to cover the opening at the rear of the motor housing portion 16. The rear cover 3 is made of synthetic resin.

[0061] The gear case 4 is connected to a front portion of the motor accommodating portion 16. The gear case 4 accommodates at least a part of the power transmission mechanism 7. The gear case 4 is cylindrical. The gear case 4 is made of metal.

[0062] The battery attachment section 5 is provided below the controller accommodating section 18 of the housing 2. The battery pack 19 is attached to the battery attachment section 5. The battery pack 19 is detachable from the battery attachment section 5. The battery pack 19 includes a secondary battery. In this embodiment, the battery pack 19 includes a rechargeable lithium ion battery. The battery pack 19 functions as a power source section for the electric work machine 1. By being attached to the battery attachment section 5, the battery pack 19 is able to supply power to the electric work machine 1.

[0063] The motor assembly 6 has a motor 20, a fan 21, and a sensor board 22A. The motor 20 is a power source for the electric work machine 1. The motor 20 has a rotor 23 and a stator 24. The rotor 23 rotates about a rotation axis AX. The fan 21 generates an airflow for cooling the motor 20. The fan 21 rotates by the rotational force generated by the motor 20. The sensor board 22A detects the rotation of the rotor 23. A detection signal from the sensor board 22A is output to the controller 9.

[0064] The motor housing 16 has an intake port 25. The rear cover 3 has an exhaust port 26. The exhaust port 26 is provided rearward of the intake port 25. The intake port 25 connects the internal space of the housing 2 to the external space. The exhaust port 26 connects the internal space of the housing 2 to the external space. The intake port 25 is provided on each of the left and right parts of the motor housing 16. The exhaust port 26 is provided on each of the left and right parts of the rear cover 3. When the fan 21 rotates, air in the external space of the housing 2 flows into the internal space of the housing 2 through the intake port 25. The air that has flowed into the internal space of the housing 2 cools the motor 20. The air in the internal space of the housing 2 flows out to the external space of the housing 2 through the exhaust port 26.

[0065] The power transmission mechanism 7 transmits the rotational force generated by the motor 20 to the spindle 8. The power transmission mechanism 7 includes a plurality of gears.

[0066] The spindle 8 rotates based on the rotational force of the motor 20 transmitted by the power transmission mechanism 7. The spindle 8 rotates about a rotation axis AX. The spindle 8 has an insertion hole into which a tool bit is inserted. A chuck mechanism 8C for holding the tool bit is provided on at least a portion of the periphery of the spindle 8. The tool bit is inserted into the insertion hole of the spindle 8 and is held by the chuck mechanism 8C.

[0067] The controller 9 controls the motor 20. The controller 9 controls the drive current supplied from the battery pack 19 to the motor 20 based on a detection signal of the sensor board 22A. The controller 9 is accommodated in the controller accommodating section 18. The controller 9 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 field effect transistor (FET), and a resistor.

[0068] The trigger switch 10 is operated by an operator to drive the motor 20. The trigger switch 10 is provided on the upper part of the grip part 17. The trigger switch 10 protrudes forward from the upper part of the front part of the grip part 17. The trigger switch 10 is operated by the operator to move it backward. The operator can move the trigger switch 10 backward, for example, with his / her index finger. The trigger switch 10 generates an operation signal when operated by the operator. The operation signal of the trigger switch 10 is input to the controller 9. The controller 9 drives the motor 20 based on the operation signal of the trigger switch 10. The motor 20 stops when the operation of the trigger switch 10 is released. The operator can stop the motor 20 by stopping the movement of the trigger switch 10 backward, for example, with his / her index finger.

[0069] The forward / reverse switching lever 11 is operated by an operator to switch the rotation direction of the motor 20 between a forward direction and a reverse direction. The forward / reverse switching lever 11 is provided at the boundary between the lower end of the motor housing portion 16 and the upper end of the grip portion 17. The forward / reverse switching lever 11 is operated by an operator to move it to the left or right. By moving the forward / reverse switching lever 11 to the left or right, the rotation direction of the motor 20 is switched. By switching the rotation direction of the motor 20, the rotation direction of the spindle 8 is switched.

[0070] The speed switch lever 12 is operated by an operator to switch the rotation speed of the spindle 8 between a first speed and a second speed. The speed switch lever 12 is provided on the upper part of the motor housing portion 16. The speed switch lever 12 is operated by an operator to move it forward or backward. By moving the speed switch lever 12 forward or backward, the rotation speed of the motor 20 is switched.

[0071] The mode change ring 13 is operated by an operator to switch the work mode of the electric work machine 1. The mode change ring 13 is disposed forward of the gear case 4. The mode change ring 13 is operated by an operator to rotate. The work modes of the electric work machine 1 include a vibration mode in which the spindle 8 vibrates in the axial direction, and a non-vibration mode in which the spindle 8 does not vibrate in the axial direction. The non-vibration mode includes a drill mode in which power is transmitted to the spindle 8 regardless of the rotational load acting on the spindle 8, and a clutch mode in which power transmitted to the spindle 8 is interrupted based on the rotational load acting on the spindle 8.

[0072] The change ring 14 is operated by an operator to set a release value at which the power transmitted to the spindle 8 is cut off. The change ring 14 is disposed forward of the mode change ring 13. The change ring 14 is operated by an operator to rotate. The release value is a value related to the rotational load acting on the spindle 8. When the rotational load acting on the spindle 8 reaches the release value, the power transmitted to the spindle 8 is cut off.

[0073] The light 15 emits illumination light that illuminates the area in front of the electric work machine 1. The light 15 includes a light emitting diode (LED). The light 15 is provided on an upper portion of the front part of the grip portion 17.

[0074] <Motor assembly> 2 is an exploded front perspective view showing the motor assembly 6 according to this embodiment. The motor assembly 6 has a motor 20, a fan 21, and a sensor board 22A.

[0075] The motor 20 is driven based on the power supplied from the battery pack 19. The motor 20 generates a rotational force for rotating the spindle 8.

[0076] The motor 20 has a rotor 23 and a stator 24. The rotor 23 rotates relative to the stator 24. In this embodiment, the motor 20 is an inner rotor type brushless motor. The stator 24 is disposed around the rotor 23. The rotor 23 rotates about a rotation axis AX.

[0077] The rotor 23 has a rotor core 27 , a rotor shaft 28 , and a permanent magnet 29 .

[0078] Rotor core 27 includes a plurality of stacked steel plates. The steel plates are made of a metal whose main component is iron. Rotor core 27 is disposed to surround rotation axis AX. Rotor core 27 has end face 27F facing forward, end face 27R facing rearward, and outer surface 27S facing radially outward.

[0079] The rotor shaft 28 extends in the axial direction. The rotor shaft 28 is disposed inside the rotor core 27. The rotor core 27 and the rotor shaft 28 are fixed. The front portion of the rotor shaft 28 protrudes forward from an end face 27F of the rotor core 27. The rear portion of the rotor shaft 28 protrudes rearward from an end face 27R of the rotor core 27. The front portion of the rotor shaft 28 is rotatably supported by a front bearing (not shown). The rear portion of the rotor shaft 28 is rotatably supported by a rear bearing (not shown). The front end portion of the rotor shaft 28 is connected to the power transmission mechanism 7.

[0080] The permanent magnets 29 are supported by the rotor core 27. In this embodiment, four permanent magnets 29 are arranged around the rotation axis AX. The rotor core 27 and the permanent magnets 29 are fixed. An example of the permanent magnets 29 is a neodymium-iron-boron magnet. The permanent magnets 29 are plate-shaped. The permanent magnets 29 are arranged inside the rotor core 27. The motor 20 is an interior permanent magnet (IPM) motor. The rotor core 27 has a magnet hole 30. The magnet hole 30 extends in the axial direction. The permanent magnets 29 are arranged in the magnet hole 30. A resin 31 is filled in a gap between an outer surface of the permanent magnet 29 and an inner surface of the magnet hole 30.

[0081] A recess 32 is formed in the outer surface 27S of the rotor core 27. The recess 32 extends in the axial direction. A front end of the recess 32 is connected to the end surface 27F of the rotor core 27. A rear end of the recess 32 is connected to the end surface 27R of the rotor core 27. A plurality of recesses 32 are provided in the outer surface 27S of the rotor core 27. In this embodiment, four recesses 32 are provided around the rotation axis AX. The plurality of recesses 32 are disposed at equal intervals in the circumferential direction. The recesses 32 are provided to suppress the generation of noise caused by the rotation of the rotor core 27. It is noted that the recesses 32 may be omitted.

[0082] The fan 21 generates an airflow for cooling the motor 20. The fan 21 is disposed rearward of the stator 24 and the rotor core 27. The fan 21 is fixed to the rear of the rotor shaft 28. At least a portion of the fan 21 is disposed in a position facing an end face 27R of the rotor core 27. The fan 21 rotates due to the rotational force generated by the motor 20. When the rotor shaft 28 rotates, the fan 21 rotates together with the rotor shaft 28.

[0083] FIG. 3 is a rear perspective view showing the stator 24 and the sensor board 22A according to this embodiment. FIG. 4 is a front view of the stator 24 and the sensor board 22A according to this embodiment. FIG. 5 is a front view of the stator 24 according to this embodiment. In FIG. 5, the sensor board 22A is shown in phantom lines. FIG. 6 is a rear view of the stator 24 and the sensor board 22A according to this embodiment. FIG. 7 is a left view of the stator 24 and the sensor board 22A according to this embodiment. FIG. 8 is a cross-sectional view of the stator 24 and the sensor board 22A according to this embodiment. FIG. 9 is an exploded front perspective view of the stator 24 and the sensor board 22A according to this embodiment.

[0084] As shown in FIGS. 2, 3, 4, 5, 6, 7, 8, and 9, the stator 24 includes a stator core 33, an insulator 34, a coil 35, and a short-circuit member 36.

[0085] The stator core 33 includes a plurality of stacked steel plates. The steel plates are metal plates whose main component is iron. The stator core 33 is disposed around the rotor core 27 of the rotor 23.

[0086] The stator core 33 has a yoke portion 37 and teeth portions 38. The yoke portion 37 is arranged to surround the rotation axis AX. The yoke portion 37 is cylindrical. The teeth portions 38 protrude radially inward from the inner peripheral surface of the yoke portion 37. A plurality of teeth portions 38 are provided in the circumferential direction. In this embodiment, six teeth portions 38 are provided. The plurality of teeth portions 38 are arranged at intervals in the circumferential direction.

[0087] The insulator 34 is an electrical insulating member made of synthetic resin. The insulator 34 is fixed to the stator core 33. The insulator 34 is arranged so as to cover at least a part of the surface of the stator core 33. In this embodiment, the insulator 34 includes a front insulator 34F fixed to the front part of the stator core 33 and a rear insulator 34R fixed to the rear part of the stator core 33. The front insulator 34F is arranged so as to cover the end face 37F of the yoke part 37 facing the front side and the front surface of the teeth part 38. The rear insulator 34R is arranged so as to cover the end face 37R of the yoke part 37 facing the rear side and the rear surface of the teeth part 38.

[0088] The coil 35 is fixed to the insulator 34. The coil 35 is wound around each of the teeth 38 via the insulator 34. A plurality of coils 35 are provided at intervals in the circumferential direction. In this embodiment, six coils 35 are provided.

[0089] The front insulator 34F has an annular portion 48 and a terminal support portion 47 protruding downward from a lower portion of the annular portion 48. The annular portion 48 is provided with an inner coil stop portion 41, an outer coil stop portion 42, and a screw boss portion 43. The terminal support portion 47 is provided with a screw hole 46. The rear insulator 34R has an annular portion 49. The annular portion 49 is provided with an inner coil stop portion 44 and an outer coil stop portion 45.

[0090] The annular portion 48 is positioned so as to cover the end face 37F of the yoke portion 37. The inner coil stopping portion 41 is connected to the annular portion 48. The inner coil stopping portion 41 is positioned radially inward from the coil 35. The inner coil stopping portion 41 supports the coil 35 from the radially inner side. The outer coil stopping portion 42 protrudes forward from the annular portion 48. The outer coil stopping portion 42 is positioned radially outward from the coil 35. The outer coil stopping portion 42 supports the coil 35 from the radially outer side.

[0091] The screw boss portion 43 has a screw hole. The screw boss portion 43 protrudes forward from the annular portion 48. Two screw boss portions 43 are provided. One screw boss portion 43 is provided in the lower left portion of the annular portion 48. The other screw boss portion 43 is provided in the lower right portion of the annular portion 48. The screw hole 46 is provided in the terminal support portion 47. Three screw holes 46 are provided. The three screw holes 46 are arranged in the left-right direction.

[0092] The annular portion 49 is positioned so as to cover the end face 37R of the yoke portion 37. The inner coil stopping portion 44 is connected to the annular portion 49. The inner coil stopping portion 44 is positioned radially inward from the coil 35. The inner coil stopping portion 44 supports the coil 35 from the radially inner side. The outer coil stopping portion 45 protrudes rearward from the annular portion 49. The outer coil stopping portion 45 is positioned radially outward from the coil 35. The outer coil stopping portion 45 supports the coil 35 from the radially outer side.

[0093] The coils 35 are formed by winding a single wire. The coils 35 adjacent to each other in the circumferential direction are connected by a crossover wire that is a part of the wire. The crossover wire is supported by an insulator 34.

[0094] Each of the six coils 35 is assigned to one of the U (UV) phase, V (VW) phase, and W (WU) phase. Of the six coils 35, two coils 35 are U-phase coils assigned to the U phase, two coils 35 are V-phase coils assigned to the V phase, and two coils 35 are W-phase coils assigned to the W phase.

[0095] The short-circuit member 36 is a conductive member. The driving current from the battery pack 19 is supplied to the short-circuit member 36 via the controller 9. The driving current supplied from the battery pack 19 to the short-circuit member 36 is controlled by the controller 9. The driving current flows through the short-circuit member 36. The short-circuit member 36 sends the driving current from the battery pack 19 to the coil 35.

[0096] In this embodiment, three short-circuit members 36 are provided. Each of the three short-circuit members 36 is assigned to one of the U-phase, V-phase, and W-phase. Of the three short-circuit members 36, one short-circuit member 36 is a U-phase short-circuit member assigned to the U-phase, one short-circuit member 36 is a V-phase short-circuit member assigned to the V-phase, and one short-circuit member 36 is a W-phase short-circuit member assigned to the W-phase.

[0097] The short-circuit member 36 has a power supply terminal 39 and a fusing terminal (not shown). The power supply terminal 39 is disposed at the bottom of the short-circuit member 36. The three power supply terminals 39 are supported by a terminal support portion 47. The three power supply terminals 39 are disposed in the left-right direction. The power supply terminals 39 are connected to the battery pack 19 via the controller 9.

[0098] A driving current from the battery pack 19 is supplied to power supply terminals 39 via power supply lines (not shown). One power supply line is fixed to one power supply terminal 39. Of the three power supply lines, one power supply line is a U-phase power supply line fixed to the power supply terminal 39 of the U-phase short-circuit member, one power supply line is a V-phase power supply line fixed to the power supply terminal 39 of the V-phase short-circuit member, and one power supply line is a W-phase power supply line fixed to the power supply terminal 39 of the W-phase short-circuit member.

[0099] The power line and the power terminal 39 are fixed together by a screw 52. The screw 52 is inserted into a screw opening 40 provided in the power terminal 39, and then inserted into a screw hole 46 provided in the terminal support portion 47.

[0100] The short-circuit member 36 is connected to the coil 35 via a fusing terminal (not shown). The short-circuit member 36 connects a power supply terminal 39 and the fusing terminal. A driving current from the battery pack 19 is supplied to the power supply terminal 39 of the short-circuit member 36 via the controller 9 and the power line. The driving current supplied from the battery pack 19 to the power supply terminal 39 flows through the short-circuit member 36 including the power supply terminal 39, and is then supplied to the coil 35.

[0101] The drive current supplied from the battery pack 19 to the motor 20 includes a U-phase drive current, a V-phase drive current, and a W-phase drive current. The U-phase drive current is supplied to a U-phase power terminal via a U-phase power line, and then supplied to a U-phase coil via a U-phase short-circuit member. The V-phase drive current is supplied to a V-phase power terminal via a V-phase power line, and then supplied to a V-phase coil via a V-phase short-circuit member. The W-phase drive current is supplied to a W-phase power terminal via a W-phase power line, and then supplied to a W-phase coil via a W-phase short-circuit member.

[0102] The short-circuit member 36 has a screw opening 50 that is aligned with the screw boss portion 43. The short-circuit member 36 is fixed to the front insulator 34F by a screw 51. The screw 51 is inserted into the screw opening 50 provided in the short-circuit member 36, and then inserted into a screw hole in the screw boss portion 43.

[0103] The sensor board 22A detects the rotation of the rotor 23. At least a portion of the sensor board 22A is disposed at a position facing an end surface 27F of the rotor 23 in the axial direction.

[0104] The sensor board 22A has a rotation sensor 60, a plate 70, and a signal line 80. In Fig. 5, the plate 70 is shown by a phantom line.

[0105] The rotation sensor 60 detects the rotation of the rotor 23. The rotation sensor 60 detects the position of the rotor 23 in the rotation direction by detecting the position of the permanent magnet 29 supported by the rotor core 27. The rotation sensor 60 is a magnetic sensor including a Hall element. Three rotation sensors 60 are provided. The three rotation sensors 60 are arranged on a virtual circle centered on the rotation axis AX. The three rotation sensors 60 are arranged at intervals of 60° around the rotation axis AX.

[0106] The rotation sensor 60 is disposed at a position facing an axial end face 27F of the rotor core 27. The rotation sensor 60 is disposed radially inward of the coil 35. The rotation sensor 60 is disposed radially inward of the inner coil stopper portion 41.

[0107] If the position of the upper end in the circumferential direction is 0°, the position of the left end in the circumferential direction is 90°, the position of the lower end in the circumferential direction is 180°, and the position of the right end in the circumferential direction is 270°, the power supply terminal 39 is disposed at 180°. The first rotation sensor 60 is disposed at 120°, the second rotation sensor 60 is disposed at 240°, and the third rotation sensor 60 is disposed at 180°.

[0108] The plate 70 supports the rotation sensor 60. The plate 70 is a parallel plate. The front surface of the plate 70 facing the forward side is a substantially flat surface. The rear surface of the plate 70 facing the rear side is a substantially flat surface. The front surface of the plate 70 and the rear surface of the plate 70 are substantially parallel to each other. The plate 70 includes a printed wiring board (PWB). The plate 70 is manufactured by cutting a single rectangular printed wiring board (PWB).

[0109] The plate 70 has an arc portion 71 and an arm portion 72 .

[0110] The arc portion 71 is disposed at a portion around the rotation axis AX. The arc portion 71 has a facing surface 71A that faces the end surface 27F of the rotor 23 in the axial direction, and a reverse surface 71B that faces in the opposite direction to the facing surface 71A. The rotation sensor 60 is disposed on the facing surface 71A. In the embodiment, the facing surface 71A is a portion of the rear surface of the plate 70 that faces the rear side. The reverse surface 71B is a portion of the front surface of the plate 70 that faces the front side.

[0111] The arc portion 71 is disposed at a position facing an axial end surface 27F of the rotor core 27. The arc portion 71 is disposed radially inward of the coils 35. The arc portion 71 is disposed radially inward of the inner coil stopper portion 41.

[0112] If the position of the upper end in the circumferential direction is 0°, the position of the left end in the circumferential direction is 90°, the position of the lower end in the circumferential direction is 180°, and the position of the right end in the circumferential direction is 270°, the arc portion 71 is disposed in a range from approximately 110° to 250°. The first rotation sensor 60 is disposed at one end of the arc portion 71 in the circumferential direction, the second rotation sensor 60 is disposed at the other end of the arc portion 71 in the circumferential direction, and the third rotation sensor 60 is disposed at the center of the arc portion 71 in the circumferential direction.

[0113] The arm portion 72 protrudes radially outward from the arc portion 71. At least two arm portions 72 are provided. In this embodiment, the arm portion 72 includes a first arm portion 721, a second arm portion 722, and a third arm portion 723. The first arm portion 721 protrudes radially outward from one end of the circumferential arc portion 71. The second arm portion 722 protrudes radially outward from the other end of the circumferential arc portion 71. The third arm portion 723 protrudes radially outward from the center of the circumferential arc portion 71. In the radial direction, the dimensions of the first arm portion 721 and the second arm portion 722 are equal. In the radial direction, the dimensions of the third arm portion 723 are larger than the dimensions of the first arm portion 721 and the second arm portion 722. In the radial direction, the distance between the rotation axis AX and the radially outer end of the third arm portion 723 is longer than the distance between the rotation axis AX and the radially outer end of the first arm portion 721 (second arm portion 722).

[0114] An end of the radially outer arm portion 72 is disposed radially outward from the coil 35. An end of the radially outer first arm portion 721, an end of the radially outer second arm portion 722, and an end of the radially outer third arm portion 723 are each disposed radially outward from the coil 35.

[0115] The plate 70 is fixed to the front insulator 34F. The arm portion 72 and the front insulator 34F are fixed. In the embodiment, an end of the first arm portion 721 and an end of the second arm portion 722 on the radially outer side are fixed to the front insulator 34F. A screw opening 53 is provided at each of the end of the first arm portion 721 and the end of the second arm portion 722 on the radially outer side. Each of the first arm portion 721 and the second arm portion 722 is fixed to the front insulator 34F by a screw 51. The screw 51 is inserted into the screw opening 53 and a screw opening 50 provided in the short-circuit member 36, and then inserted into a screw hole of the screw boss portion 43.

[0116] The third arm portion 723 is disposed in front of the power supply terminal 39. The third arm portion 723 is disposed so as to overlap the power supply terminal 39 in a plane perpendicular to the rotation axis AX.

[0117] The signal line 80 connects the rotation sensor 60 and the controller 9. A detection signal of the rotation sensor 60 is transmitted to the controller 9 via the signal line 80. The controller 9 controls the drive current supplied from the battery pack 19 to the coil 35 based on the detection signal of the rotation sensor 60. Five signal lines 80 are provided. The signal lines 80 are supported by the third arm portion 723. The signal lines 80 are disposed on the front surface of the third arm portion 723.

[0118] In the axial direction, the facing surface 71A is disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In the axial direction, the reverse surface 71B is also disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. That is, the facing surface 71A and the reverse surface 71B are disposed rearward of the front end 35F of the coil 35. In this embodiment, the plate 70 is a parallel plate. In the axial direction, the rear surface and the front surface of the plate 70 are disposed rearward of the front end 35F of the coil 35. The arc portion 71 supporting the rotation sensor 60 is disposed radially inward of the coil 35 so that the rotation sensor 60 does not come into contact with the rotor core 27 and the permanent magnet 29.

[0119] The arm portion 72 is disposed between a pair of coils 35 adjacent to each other in the circumferential direction. If the position of the upper end in the circumferential direction is the position of 0 [°], the position of the left end in the circumferential direction is the position of 90 [°], the position of the lower end in the circumferential direction is the position of 180 [°], and the position of the right end in the circumferential direction is the position of 270 [°], the first coil 35 is disposed at the position of 30 [°], the second coil 35 is disposed at the position of 90 [°], the third coil 35 is disposed at the position of 150 [°], the fourth coil 35 is disposed at the position of 210 [°], the fifth coil 35 is disposed at the position of 270 [°], and the sixth coil 35 is disposed at the position of 330 [°]. The first arm portion 721 is disposed at the position of 120 [°], the third arm portion 723 is disposed at the position of 180 [°], and the second arm portion 722 is disposed at the position of 240 [°]. At least a portion of the first arm portion 721 is disposed between the second coil 35 and the third coil 35. At least a portion of the third arm portion 723 is disposed between the third coil 35 and the fourth coil 35. At least a portion of the second arm portion 722 is disposed between the fourth coil 35 and the fifth coil 35.

[0120] <Effects> As described above, in this embodiment, the electric operating machine 1 may include the motor 20 having the rotor 23 rotating about the rotation axis AX and the stator 24 arranged around the rotor 23, the sensor board 22A having the rotation sensor 60 that detects the rotation of the rotor 23, and the plate 70 that supports the rotation sensor 60. The stator 24 may include a stator core 33 arranged around the rotor 23, an insulator 34 fixed to the stator core 33, and a plurality of coils 35 fixed to the insulator 34 and arranged at intervals in the circumferential direction. The plate 70 may include a circular arc portion 71 arranged in a part of the circumference of the rotation axis AX and having a facing surface 71A facing the end surface 27F of the rotor 23 in the axial direction, and at least two arm portions 72 that protrude radially outward from the circular arc portion 71 and are fixed to the insulator 34. The rotation sensor 60 may be arranged on the facing surface 71A.

[0121] In the above configuration, part of the plate 70 of the sensor board 22A is the arc portion 71, which reduces the size and weight of the sensor board 22A. Part of the plate 70 that is fixed to the insulator 34 is the arm portion 72, which reduces the size and weight of the sensor board 22A. By reducing the size and weight of the sensor board 22A, the motor assembly 6 including the motor 20 and the sensor board 22A is reduced in size and weight. This reduces the size and weight of the electric work machine 1. Also, a large number of plates 70 are manufactured from a single rectangular printed wiring board (PWB: Printed Wiring Board).

[0122] In the present embodiment, the arc portion 71 may be disposed radially inward of the coil 35 .

[0123] In the above configuration, the motor assembly 6 is made smaller in size in the radial direction.

[0124] In the present embodiment, the end of the radially outer arm portion 72 may be disposed radially outward of the coil 35. The end of the arm portion 72 may be fixed to the insulator 34.

[0125] In the above configuration, the end of the arm portion 72 is fixed to the insulator , whereby the sensor board 22A is fixed to the insulator .

[0126] In the present embodiment, the opposing surface 71A may be disposed at a position closer to the center of the coil 35 than the front end portion 35F of the coil 35 in the axial direction.

[0127] In the above configuration, at least a portion of the arc portion 71 fits into the radial inside of the coil 35, thereby reducing the size of the motor assembly 6 in the axial direction.

[0128] In the present embodiment, the arc portion 71 may have a reverse surface 71B that faces in the opposite direction to the opposing surface 71 A. In the axial direction, the reverse surface 71B may be located closer to the center of the coil 35 than the front end portion 35F of the coil 35.

[0129] In the above configuration, the entire arc portion 71 fits radially inside the coil 35, making the motor assembly 6 smaller in size in the axial direction.

[0130] In this embodiment, the plate 70 may be a parallel plate.

[0131] In the above configuration, the plate 70 is manufactured from a printed wiring board (PWB).

[0132] In the present embodiment, the arm portion 72 may be disposed between a pair of coils 35 adjacent to each other.

[0133] In the above configuration, even if the plate 70 is a parallel flat plate, at least a part of the arcuate portion 71 enters inside the coil 35 in the radial direction.

[0134] In the present embodiment, the arm portion 72 may include a first arm portion 721 and a second arm portion 722. The first arm portion 721 may protrude radially outward from one end of the circumferential arc portion 71, and the second arm portion 722 may protrude radially outward from the other end of the circumferential arc portion 71.

[0135] In the above configuration, the end of the circumferential arc portion 71 is prevented from bending or vibrating.

[0136] In this embodiment, the arm portion 72 may include a third arm portion 723. The third arm portion 723 may protrude radially outward from the center of the arc portion 71 in the circumferential direction.

[0137] In the above configuration, the first arm portion 721, the second arm portion 722, and the third arm portion 723 are each fixed to the insulator , so that the sensor board 22A is sufficiently fixed to the insulator .

[0138] In this embodiment, the electric operating machine 1 may include a controller 9 that controls the drive current supplied to the coil 35 based on a detection signal of the rotation sensor 60, and a signal line 80 that connects the rotation sensor 60 and the controller 9. The signal line 80 may be supported by the third arm portion 723.

[0139] In the above configuration, the signal line 80 is supported by the third arm portion 723 of the plate 70.

[0140] In this embodiment, the electric operating machine 1 may include a power supply terminal 39 through which a drive current flows. The third arm portion 723 may be disposed so as to overlap the power supply terminal 39 in a plane perpendicular to the rotation axis AX.

[0141] In the above configuration, the motor assembly 6 is prevented from becoming large in size in the radial direction.

[0142] In this embodiment, each of the first arm portion 721 and the second arm portion 722 may be fixed to the insulator 34 by a screw 51.

[0143] In the above configuration, by removing the screws 51, the sensor board 22A can be easily replaced with a new sensor board 22A.

[0144] In this embodiment, it is sufficient that at least one of the first arm portion 721, the second arm portion 722, and the third arm portion 723 is fixed to the insulator 34 by the screw 51. For example, the third arm portion 723 may be fixed to the insulator 34 by the screw 51, and the first arm portion 721 and the second arm portion 722 may not be fixed to the insulator 34. Furthermore, all of the first arm portion 721, the second arm portion 722, and the third arm portion 723 may be fixed to the insulator 34 by the screw 51.

[0145] [Second embodiment] A second embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0146] Fig. 10 is a view of the stator 24 and the sensor board 22B according to this embodiment as viewed from the front. Fig. 11 is a view of the stator 24 according to this embodiment as viewed from the front. Fig. 12 is a view of the stator 24 and the sensor board 22B according to this embodiment as viewed from the left. Fig. 13 is a cross-sectional view showing the stator 24 and the sensor board 22B according to this embodiment. In Fig. 11, the plate 70 is shown by virtual lines.

[0147] In this embodiment, the plate 70 has an arc portion 71, a first arm portion 721, a second arm portion 722, a third arm portion 723, and a cover portion 73 that connects the radially outer end of the first arm portion 721, the end of the second arm portion 722, and the end of the third arm portion 723. The cover portion 73 is disposed radially outward from the coil 35. In this embodiment, the plate 70 has two openings. One opening is defined by the arc portion 71, the first arm portion 721, the second arm portion 722, and the cover portion 73. The other opening is defined by the arc portion 71, the second arm portion 722, the second arm portion 722, and the cover portion 73. In a plane perpendicular to the rotation axis AX, one opening overlaps at least a portion of one coil 35, and the other opening overlaps at least a portion of one coil 35.

[0148] The cover portion 73 is disposed in front of the power supply terminal 39. In a plane perpendicular to the rotation axis AX, the cover portion 73 is disposed so as to overlap the power supply terminal 39. The signal line 80 is supported on the front surface of the cover portion 73.

[0149] In the axial direction, the facing surface 71A is disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In the axial direction, the reverse surface 71B is also disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed rearward of the front end 35F of the coil 35.

[0150] As described above, in this embodiment, the plate 70 may have a cover portion 73 that connects the radially outer end of the first arm portion 721, the end of the second arm portion 722, and the end of the third arm portion 723.

[0151] In the above configuration, the strength of the plate 70 is improved.

[0152] In this embodiment, the electric operating machine 1 may include a controller 9 that controls the drive current supplied to the coil 35 based on a detection signal of the rotation sensor 60, and a signal line 80 that connects the rotation sensor 60 and the controller 9. The signal line 80 may be supported by the cover portion 73.

[0153] In the above configuration, the signal line 80 is supported by the cover portion 73 of the plate 70 .

[0154] In this embodiment, the electric operating machine 1 may include a power supply terminal 39 through which a drive current flows. The cover portion 73 may be disposed so as to overlap the power supply terminal 39 in a plane perpendicular to the rotation axis AX.

[0155] In the above configuration, the motor assembly 6 is prevented from becoming large in size in the radial direction.

[0156] [Third embodiment] A third embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0157] FIG. 14 is a view of the stator 24 and the sensor board 22C according to this embodiment as viewed from the front. FIG. 15 is a view of the stator 24 according to this embodiment as viewed from the front. FIG. 16 is a view of the stator 24 and the sensor board 22C according to this embodiment as viewed from the left. FIG. 17 is a cross-sectional view showing the stator 24 and the sensor board 22C according to this embodiment. FIG. 18 is an exploded perspective view of the stator 24 and the sensor board 22C according to this embodiment as viewed from the front. FIG. 19 is a cross-sectional view showing the stator 24 and the sensor board 22C according to this embodiment. In FIG. 15, the plate 70 is shown by a virtual line. FIG. 19 corresponds to the cross-sectional view taken along the line AA in FIG. 14.

[0158] The plate 70 has a circular arc portion 71, a first arm portion 721, a second arm portion 722, and a third arm portion 723. In this embodiment, the motor assembly 6 has a support member 90 fixed to the front insulator 34F.

[0159] At least two arm portions 72 are fixed to the front insulator 34F via a support member 90. In this embodiment, each of the first arm portion 721 and the second arm portion 722 is fixed to the support member 90 by a screw 51 (second screw).

[0160] The support member 90 has a support arc portion 94 and a threaded boss portion 92 .

[0161] The support arc portion 94 is disposed on a portion of the circumference of the rotation axis AX. The support arc portion 94 is disposed radially outward of the coil 35. In a plane perpendicular to the rotation axis AX, the support arc portion 94 is disposed so as to overlap with the annular portion 48 of the front insulator 34F.

[0162] When the upper circumferential end is positioned at 0°, the left circumferential end is positioned at 90°, the lower circumferential end is positioned at 180°, and the right circumferential end is positioned at 270°, the support arc portion 94 is positioned in the range of approximately 110° to 250°.

[0163] The support arc portion 94 is fixed to the front insulator 34F by a screw 54 (first screw). A screw opening 93 is provided at each of one end and the other end of the support arc portion 94 in the circumferential direction. The screw 54 is inserted into the screw opening 50 provided in the short-circuit member 36, and then inserted into a screw hole of the screw boss portion 43 provided in the front insulator 34F.

[0164] The screw boss portion 92 is connected to one end and the other end of the circumferential support arc portion 94. The screw boss portion 92 is disposed radially inward of the support arc portion 94. The two arm portions 72 are fixed to the screw boss portion 92 by a screw 51 (second screw). The first arm portion 721 is fixed to one screw boss portion 92 by a screw 51, and the second arm portion 722 is fixed to the other screw boss portion 92 by a screw 51. One screw 51 is inserted into a screw opening 53 provided in the first arm portion 721, and then inserted into a screw hole of one screw boss portion 92. The other screw 51 is inserted into a screw opening 53 provided in the second arm portion 722, and then inserted into a screw hole of the other screw boss portion 92.

[0165] A recess 91 is provided in the center of the support arc portion 94 in the circumferential direction. The recess 91 is recessed rearward from the front surface of the support arc portion 94. At least a portion of the third arm portion 723 is disposed in the recess 91.

[0166] The arc portion 71 is disposed radially inward of the supporting arc portion 94. The arc portion 71 is disposed radially outward of the coil 35.

[0167] As shown in FIG. 19 , the screw boss portion 92 has an end face 92R that faces the same direction as the opposing surface 71A. The end face 92R faces rearward. The end face 92R is the rear end face of the screw boss portion 92. The end face 37F of the yoke portion 37 of the stator core 33 faces the opposite direction to the opposing surface 71A. In the axial direction, the end face 92R of the screw boss portion 92 is located closer to the center of the coil 35 than the end face 37F of the yoke portion 37 of the stator core 33. In other words, the end face 92R of the screw boss portion 92 is located rearward of the end face 37F of the yoke portion 37 of the stator core 33.

[0168] In the axial direction, the facing surface 71A is disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In the axial direction, the reverse surface 71B is also disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed rearward of the front end 35F of the coil 35.

[0169] As described above, in this embodiment, the electric operating machine 1 may include the support member 90 fixed to the insulator 34. The at least two arm portions 72 may be fixed to the insulator 34 via the support member 90.

[0170] In the above configuration, the plate 70 is fixed to the insulator 34 via the support member 90. Even if the plate 70 is a parallel plate, the plate 70 and the insulator 34 are properly fixed to each other via the support member 90 by adjusting the shape of the support member 90.

[0171] In this embodiment, the support member 90 may have a support arc portion 94 fixed to the insulator 34 by a screw 54 that is a first screw, and a screw boss portion 92 that is arranged radially inward of the support arc portion 94 and to which the arm portion 72 is fixed by a screw 51 that is a second screw. In the axial direction, an end face 92R of the screw boss portion 92 facing the same direction as the opposing surface 71A may be arranged at a position closer to the center of the coil 35 than an end face 37F of the stator core 33 facing the opposite direction to the opposing surface 71A.

[0172] In the above configuration, the plate 70 is stably fixed to the insulator 34 via the support member 90. The screw boss portion 92 is disposed radially inward from the support arc portion 94, so the length of the screw boss portion 92 is not restricted. That is, the screw boss portion 92 is disposed radially inward from the yoke portion 37 of the stator core 33 and disposed between a pair of adjacent teeth portions 38, so the length of the screw boss portion 92 is not restricted. In a case where the plate 70 is disposed rearward from the front end portion 35F of the coil 35 and the plate 70 is fixed to the insulator 34 by the screw 51, if the screw 51 is long, the tip portion of the screw 51 may hit the end face 37F of the stator core 33, so that it may be necessary to shorten the screw 51. If the screw 51 is short, the fixing between the plate 70 and the insulator 34 may become unstable. In this embodiment, since there is no restriction on the length of the screw boss portion 92, a long screw 51 can be used even when the plate 70 is disposed rearward of the front end portion 35F of the coil 35. Therefore, the plate 70 is stably fixed to the insulator 34 via the support member 90.

[0173] [Fourth embodiment] A fourth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0174] Fig. 20 is a view of the stator 24 and the sensor board 22D according to this embodiment as viewed from the front. Fig. 21 is a view of the stator 24 according to this embodiment as viewed from the front. Fig. 22 is a view of the stator 24 and the sensor board 22D according to this embodiment as viewed from the left. Fig. 23 is a cross-sectional view showing the stator 24 and the sensor board 22D according to this embodiment. In Fig. 21, the plate 70 is shown by virtual lines.

[0175] In this embodiment, the plate 70 has an arc portion 71, a first arm portion 721, a second arm portion 722, and a bridge portion 74 connecting a radially outer end of the first arm portion 721 and an end of the second arm portion 722. The bridge portion 74 is disposed radially outer than the coil 35. In this embodiment, the plate 70 does not have a third arm portion 723.

[0176] The bridge portion 74 has an arc shape and is disposed on a portion of the circumference of the rotation axis AX. The bridge portion 74 is disposed radially outward from the coil 35. In a plane perpendicular to the rotation axis AX, the bridge portion 74 is disposed so as to overlap the annular portion 48 of the front insulator 34F.

[0177] When the upper circumferential end is positioned at 0°, the left circumferential end is positioned at 90°, the lower circumferential end is positioned at 180°, and the right circumferential end is positioned at 270°, bridge portion 74 is positioned in the range of approximately 110° to 250°.

[0178] In this embodiment, the plate 70 has one opening. The opening is defined by the arc portion 71, the first arm portion 721, the second arm portion 722, and the bridge portion 74. The opening and the two coils 35 overlap in a plane perpendicular to the rotation axis AX.

[0179] The bridge portion 74 is disposed radially inward from the power supply terminal 39. The signal line 80 is supported on the front surface of the bridge portion 74.

[0180] In the axial direction, the facing surface 71A is disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In the axial direction, the reverse surface 71B is also disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed rearward of the front end 35F of the coil 35.

[0181] As described above, in this embodiment, the plate 70 may have the bridge portion 74 that connects the end of the first arm portion 721 and the end of the second arm portion 722 on the outer side in the radial direction.

[0182] In the above configuration, the strength of the plate 70 is improved.

[0183] In this embodiment, the bridge portion 74 may be an arc-shaped portion disposed around a portion of the rotation axis AX.

[0184] In the above configuration, the motor assembly 6 is prevented from becoming large in size in the radial direction.

[0185] In this embodiment, the electric operating machine 1 may include a controller 9 that controls the drive current supplied to the coil 35 based on a detection signal of the rotation sensor 60, and a signal line 80 that connects the rotation sensor 60 and the controller 9. The signal line 80 may be supported by the bridge portion 74.

[0186] In the above configuration, the signal line 80 is supported by the bridge portion 74 of the plate 70 .

[0187] [Fifth embodiment] A fifth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0188] Fig. 24 is a view of the stator 24 and the sensor board 22A according to this embodiment as viewed from the front. Fig. 25 is a view of the stator 24 and the sensor board 22A according to this embodiment as viewed from the left. Fig. 26 is a cross-sectional view showing the stator 24 and the sensor board 22A according to this embodiment.

[0189] This embodiment is a modified example of the first embodiment. In the first embodiment, the opposing surface 71A and the reverse surface 71B of the sensor substrate 22A are arranged closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, the opposing surface 71A and the reverse surface 71B are arranged rearward of the front end 35F of the coil 35.

[0190] In this embodiment, each of the facing surface 71A and the reverse surface 71B of the sensor substrate 22A is disposed at a position farther from the center of the coil 35 than the front end portion 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed forward of the front end portion 35F of the coil 35.

[0191] As described above, each of the facing surface 71A and the reverse surface 71B of the sensor board 22A may be disposed forward of the front end portion 35F of the coil 35.

[0192] [Sixth embodiment] A sixth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0193] Fig. 27 is a view of the stator 24 and the sensor board 22B according to this embodiment as viewed from the front. Fig. 28 is a view of the stator 24 and the sensor board 22B according to this embodiment as viewed from the left. Fig. 29 is a cross-sectional view showing the stator 24 and the sensor board 22B according to this embodiment.

[0194] This embodiment is a modified example of the second embodiment. In the second embodiment, the opposing surface 71A and the reverse surface 71B of the sensor substrate 22B are arranged closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, the opposing surface 71A and the reverse surface 71B are arranged rearward of the front end 35F of the coil 35.

[0195] In this embodiment, each of the facing surface 71A and the reverse surface 71B of the sensor substrate 22B is disposed at a position farther from the center of the coil 35 than the front end portion 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed forward of the front end portion 35F of the coil 35.

[0196] As described above, each of the facing surface 71A and the reverse surface 71B of the sensor board 22B may be disposed forward of the front end portion 35F of the coil 35.

[0197] [Seventh embodiment] A seventh embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0198] Fig. 30 is a view of the stator 24 and the sensor board 22C according to the present embodiment as viewed from the front. Fig. 31 is a view of the stator 24 and the sensor board 22C according to the present embodiment as viewed from the left. Fig. 33 is a cross-sectional view showing the stator 24 and the sensor board 22C according to the present embodiment.

[0199] This embodiment is a modified example of the above-described third embodiment. In the above-described third embodiment, the opposing surface 71A and the reverse surface 71B of the sensor substrate 22C are arranged closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, the opposing surface 71A and the reverse surface 71B are arranged rearward of the front end 35F of the coil 35.

[0200] In this embodiment, each of the facing surface 71A and the reverse surface 71B of the sensor substrate 22C is disposed at a position farther from the center of the coil 35 than the front end portion 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed forward of the front end portion 35F of the coil 35.

[0201] As described above, each of the facing surface 71A and the reverse surface 71B of the sensor board 22C may be disposed forward of the front end portion 35F of the coil 35.

[0202] [Eighth embodiment] An eighth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0203] Fig. 33 is a view of the stator 24 and the sensor board 22D according to this embodiment as viewed from the front. Fig. 34 is a view of the stator 24 and the sensor board 22D according to this embodiment as viewed from the left. Fig. 35 is a cross-sectional view showing the stator 24 and the sensor board 22D according to this embodiment.

[0204] This embodiment is a modified example of the above-mentioned fourth embodiment. In the above-mentioned fourth embodiment, the opposing surface 71A and the reverse surface 71B of the sensor substrate 22D are arranged closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, the opposing surface 71A and the reverse surface 71B are arranged rearward of the front end 35F of the coil 35.

[0205] In this embodiment, each of the facing surface 71A and the reverse surface 71B of the sensor substrate 22D is disposed at a position farther from the center of the coil 35 than the front end portion 35F of the coil 35. In other words, each of the facing surface 71A and the reverse surface 71B is disposed forward of the front end portion 35F of the coil 35.

[0206] As described above, each of the facing surface 71A and the reverse surface 71B of the sensor board 22D may be disposed forward of the front end portion 35F of the coil 35.

[0207] [Ninth embodiment] A ninth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0208] Fig. 36 is a front view of the stator 24 and the sensor board 22E according to this embodiment. As shown in Fig. 36, the plate 70 of the sensor board 22E has an arc portion 71, an arm portion 72, and an outer arc portion 75. In this embodiment, the plate 70 has a third arm portion 723, and does not have a first arm portion 721 or a second arm portion 722. The outer arc portion 75 is connected to an end of the third arm portion 723 on the radially outer side.

[0209] The outer arc portion 75 has an arc shape and is disposed on a portion of the circumference of the rotation axis AX. The outer arc portion 75 is disposed radially outward from the coil 35. In a plane perpendicular to the rotation axis AX, the outer arc portion 75 is disposed so as to overlap the annular portion 48 of the front insulator 34F. One end and the other end of the outer arc portion 75 in the circumferential direction are fixed to the front insulator 34F by screws 51.

[0210] If the upper circumferential end is positioned at 0°, the left circumferential end is positioned at 90°, the lower circumferential end is positioned at 180°, and the right circumferential end is positioned at 270°, then the outer arc portion 75 is positioned in the range of approximately 110° to 250°.

[0211] The outer arc portion 75 is disposed radially inward of the power terminal 39. The signal line 80 is supported by the front surface of the outer arc portion 75.

[0212] In the axial direction, the facing surface 71A is disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In the axial direction, the reverse surface 71B is also disposed at a position closer to the center of the coil 35 than the front end 35F of the coil 35. In other words, the facing surface 71A and the reverse surface 71B are each disposed rearward of the front end 35F of the coil 35. Note that the facing surface 71A and the reverse surface 71B may each be disposed forward of the front end 35F of the coil 35.

[0213] As described above, the number of arm portions 72 may be one.

[0214] [Tenth embodiment] A tenth embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0215] FIG. 37 is a diagram for explaining the relationship between the facing surface 71A and the reverse surface 71B and the front end portion 35F of the coil 35 according to this embodiment.

[0216] In each of the first to ninth embodiments described above, as shown in state A of Fig. 37, both the opposing surface 71A and the reverse surface 71B may be disposed in a position farther from the center of the coil 35 than the front end portion 35F of the coil 35 in the axial direction. In other words, both the opposing surface 71A and the reverse surface 71B may be disposed forward of the front end portion 35F of the coil 35.

[0217] In each of the above-described first to ninth embodiments, as shown in state B of Figure 37, in the axial direction, the position of the opposing surface 71A may coincide with the position of the front end portion 35F of the coil 35, and the reverse surface 71B may be positioned forward of the front end portion 35F of the coil 35.

[0218] 37, the facing surface 71A may be arranged rearward of the front end 35F of the coil 35, and the reverse surface 71B may be arranged forward of the front end 35F of the coil 35. In the state C, the front end 35F of the coil 35 is arranged rearward of the center of the plate 70 in the axial direction.

[0219] 37, the facing surface 71A may be arranged rearward of the front end 35F of the coil 35, and the reverse surface 71B may be arranged forward of the front end 35F of the coil 35. In the state D, the front end 35F of the coil 35 is arranged forward of the center of the plate 70 in the axial direction.

[0220] In each of the above-described first to ninth embodiments, as shown in state E of Figure 37, in the axial direction, the opposing surface 71A may be positioned rearward of the front end portion 35F of the coil 35, and the position of the reverse surface 71B may coincide with the position of the front end portion 35F of the coil 35.

[0221] In each of the first to ninth embodiments described above, as shown in state F of Fig. 37, in the axial direction, both the opposing surface 71A and the reverse surface 71B may be disposed closer to the center of the coil 35 than the front end portion 35F of the coil 35. In other words, both the opposing surface 71A and the reverse surface 71B may be disposed rearward of the front end portion 35F of the coil 35.

[0222] [Other embodiments] In the above embodiment, the electric work machine 1 is a vibration driver drill, which is a type of power tool. The power tool is not limited to a vibration driver drill. Examples of the power tool include a driver drill, an angle drill, an impact driver, a grinder, a hammer, a hammer drill, a circular saw, and a reciprocating saw. The electric work machine 1 may also be a gardening tool (Outdoor Power Equipment). Examples of the gardening tool include a chain saw, a hedge trimmer, a lawn mower, a grass cutter, and a blower.

[0223] In the above embodiment, the battery pack 19 attached to the battery attachment portion is used as the power source for the electric working machine. A commercial power source (AC power source) may also be used as the power source for the electric working machine.

[0224] [Eleventh embodiment] An eleventh embodiment will be described below. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description of those components will be simplified or omitted.

[0225] Fig. 38 is a view of the stator and the sensor board according to the 11th embodiment as viewed from the front. Fig. 39 is an exploded perspective view of the stator and the sensor board according to the 11th embodiment as viewed from the front. Fig. 40 is a cross-sectional view of the stator and the sensor board according to the 11th embodiment. Fig. 41 is a perspective view showing a portion of the sensor board according to the 11th embodiment that is covered with a covering portion.

[0226] (Arm fixing) If any of the first arm portion 721, the second arm portion 722, and the third arm portion 723 is a free end that is not fixed, the arm portion that is the free end is likely to vibrate due to vibration during use of the electric work machine 1. Therefore, in the eleventh embodiment, the radially outer end of each arm portion 72 of the plate 70 is fixed. Specifically, the plate 70 has three arm portions 72, namely, the first arm portion 721, the second arm portion 722, and the third arm portion 723. The first arm portion 721, the second arm portion 722, and the third arm portion 723 are each fixed to the front insulator 34F. The first arm portion 721, the second arm portion 722, and the third arm portion 723 are fixed to the front insulator 34F by the screw 51.

[0227] A screw opening 53 is provided at each of the radially outer ends of the first arm portion 721 and the second arm portion 722. A screw 51 is inserted into the screw opening 53 and a screw opening 50 provided in the short-circuit member 36, and then inserted into a screw hole in the screw boss portion 43 of the front insulator 34F.

[0228] A screw opening 153 is provided at the end of the third arm portion 723 on the radially outer side. The screw 51 is inserted into the screw opening 153 and then inserted into the screw hole of the screw boss portion 143. The screw boss portion 143 is cylindrical and has a screw hole formed in its tip surface. Instead of being provided with the screw opening 50, the short-circuit member 36 is formed with a notch portion 136 for allowing the screw boss portion 143 to escape. The screw boss portion 143 passes inside the notch portion 136 and extends to the front side of the short-circuit member 36. The third arm portion 723 is directly fixed to the screw boss portion 143 of the front insulator 34F without the short-circuit member 36 being interposed therebetween.

[0229] The screw 51 may be a normal screw of the type that is coupled to a screw hole with a thread groove (female thread) formed in advance, or a tapping screw. A tapping screw is a type of screw that forms a thread groove (female thread) by itself when screwed into a pilot hole that does not have a female thread.

[0230] (positioning part) In detecting the position of the rotor 23 by the rotation sensor 60, it is important to ensure detection accuracy that there is little positional variation due to an assembly error of the rotation sensor 60. Therefore, in the eleventh embodiment, the stator 24 and the sensor board 22F have a structure for positioning the sensor board 22F relative to the stator 24. Specifically, a positioning hole 111 is formed in the sensor board 22F, and a positioning pin 112 is provided in the front insulator 34F.

[0231] The sensor substrate 22F has a plurality of positioning holes 111. Each positioning hole 111 is disposed at a different end of the sensor substrate 22F. One positioning hole 111 is provided at each of the radially outer ends of the first arm portion 721 and the second arm portion 722. The positioning holes 111 are disposed near the screw openings 53. The positioning holes 111 have a circular shape and penetrate the plate 70 in the thickness direction.

[0232] The front insulator 34F has the same number of positioning pins 112 as the number of positioning holes 111 of the sensor board 22F (i.e., two). The positioning pins 112 may be integral with the front insulator 34F or may be separate from the front insulator 34F. The two positioning pins 112 are arranged at positions overlapping the positioning holes 111 of the sensor board 22F, respectively, in a plane perpendicular to the rotation axis AX. The positioning pins 112 protrude forward from the front surface of the front insulator 34F facing the sensor board 22F. The positioning pins 112 have a cylindrical shape. When the sensor board 22F is fixed to the front insulator 34F, the positioning pins 112 are arranged inside the corresponding positioning holes 111. This determines the position of the sensor board 22F relative to the stator 24 via the front insulator 34F, and suppresses positional variation of the rotation sensor 60 caused by an assembly error.

[0233] (Reverse assembly prevention structure) When assembling the sensor board 22F to the stator 24, there is a possibility that a worker may mistakenly perform the assembling with the sensor board 22F upside down. In the eleventh embodiment, the stator 24 and the sensor board 22F have a structure that prevents the sensor board 22F from being assembled with the front and back reversed. Specifically, the sensor board 22F has an asymmetric structure with respect to a center line LC. The center line LC is a line that passes through the center in the left-right direction within the plane of the sensor board 22F.

[0234] The sensor board 22F is fixed at the end of each of the first arm portion 721, the second arm portion 722, and the third arm portion 723. The first arm portion 721 and the second arm portion 722 are symmetrical with respect to the center line LC. The screw opening 53 and the positioning hole 111 of the first arm portion 721 and the screw opening 53 and the positioning hole 111 of the second arm portion 722 are symmetrical with respect to the center line LC.

[0235] On the other hand, the third arm portion 723 is asymmetric with respect to the center line LC. The end of the third arm portion 723 has a central portion 171 along the center line LC, a first convex portion 172 protruding from the central portion 171 to one side (left side), and an other convex portion 173 protruding from the central portion 171 to the other side (right side). The first convex portion 172 and the other convex portion 173 are formed at the same position in the direction along the center line LC (up and down direction). The first convex portion 172 and the other convex portion 173 protrude from the central portion 171 in opposite directions. The third arm portion 723 has an asymmetric shape with respect to the center line LC at the first convex portion 172 and the other convex portion 173.

[0236] Specifically, a distance D1 from the center line LC to the tip of one convex portion 172 is different from a distance D2 from the center line LC to the tip of one convex portion 172. Distance D1 is greater than distance D2. One convex portion 172 is greater than the other convex portion 173. One convex portion 172 is formed with a screw opening 153. Screw opening 153 is formed at a position on the end of third arm portion 723 that is biased to one side from the center (center line LC).

[0237] The front insulator 34F has a guide rib 134 for preventing the sensor board 22F from being installed upside down. The guide rib 134 protrudes forward from the front surface of the front insulator 34F. The guide rib 134 is disposed on the other side of the center line LC. The guide rib 134 is disposed at a position adjacent to the tip of the other convex portion 173. The guide rib 134 faces the other convex portion 173 in the left-right direction. The guide rib 134 is disposed at a position farther away from the center line LC than a distance D1 and closer to the center line LC than a distance D2. As a result, the guide rib 134 is disposed at a position where it contacts the one convex portion 172 when the sensor board 22F is turned upside down.

[0238] In Fig. 38, when the sensor board 22F is turned upside down, the one-side convex portion 172 of the third arm portion 723 is disposed on the other side (right side) of the center line LC, and the other-side convex portion 173 is disposed on one side (left side) of the center line LC. In this case, the one-side convex portion 172 is disposed so as to ride on the guide rib 134, and the sensor board 22F is inclined, so that the sensor board 22F cannot be disposed in a normal posture. In addition, the position of the screw opening 153 of the one-side convex portion 172 does not match the position of the screw boss portion 143. Therefore, the worker performing the assembly can recognize that the sensor board 22F is not disposed properly.

[0239] (Covering part) In the eleventh embodiment, the sensor board 22F has a covering portion 175 that covers the rotation sensor 60 and the ends of the signal wire 80 (connection portions to the sensor board 22F). The covering portion 175 is made of resin and formed on the plate 70 by a molding method. The covering portion 175 encases and seals the rotation sensor 60 and the ends of the signal wire 80. In FIG. 41, for ease of explanation, the outer shape of the covering portion 175 is shown by a two-dot chain line, and each member covered by the covering portion 175 is shown by a solid line.

[0240] The rotation sensor 60 is disposed on an opposing surface 71A of the arc portion 71 of the plate 70 that faces the end surface 27F of the rotor 23. An end of the signal line 80 is disposed between the plate 70 and the stator core 33. An end of the signal line 80 is disposed on the same surface (opposing surface 71A) of the plate 70 as the rotation sensor 60. In other words, the end of the signal line 80 is disposed on the surface facing the stator core 33 at the end of the third arm portion 723. The end of the signal line 80 is connected to a circuit portion of the sensor board 22F at the center portion 171 of the third arm portion 723.

[0241] The covering portion 175 covers the circuit forming portion of the plate 70. The covering portion 175 covers the arc portion 71 on which the rotation sensor 60 is disposed. The covering portion 175 covers both the facing surface 71A and the reverse surface 71B of the arc portion 71. As shown in FIG. 40 , the facing surface 71A and the reverse surface 71B are each disposed on the rear side closer to the center of the coil 35 than the front end portion 35F of the coil 35. The covering portion 175 covers the central portion 171 of the third arm portion 723 of the plate 70.

[0242] The covering portion 175 is not formed at the portions of the plate 70 that come into contact with the front insulator 34F or the short-circuit member 36. The covering portion 175 exposes, without covering, the ends of the first arm portion 721 and the second arm portion 722 of the plate 70. The covering portion 175 exposes, without covering, the one convex portion 172 and the other convex portion 173 of the third arm portion 723. Since the covering portion 175 is not present at the portions of contact, misalignment of the sensor board 22F caused by dimensional errors in the covering portion 175 is prevented when the sensor board 22F is fixed.

[0243] As described above, in this embodiment, the radially outer ends of the arm portions 72 of the plate 70 are fixed.

[0244] In the above configuration, the arm portion 72 does not become a free end, so vibration of the sensor board 22F is suppressed.

[0245] In this embodiment, the screw opening 153 of the third arm portion 723 is provided in the one convex portion 172 , but the screw opening 153 may be provided in the other convex portion 173 , or the screw opening 153 may be provided in the central portion 171 .

[0246] In this embodiment, the stator 24 and the sensor substrate 22F have a positioning structure for the sensor substrate 22F relative to the stator 24.

[0247] In the above configuration, the positional variation of the rotation sensor 60 caused by an assembly error of the sensor board 22F can be reduced, so that the detection accuracy of the rotation sensor 60 can be ensured.

[0248] Alternatively, a positioning pin 112 may be formed on the sensor board 22F, and a positioning hole 111 may be provided in the front insulator 34F. That is, a positioning hole 111 may be provided in one of the sensor board 22F and the insulator 34, and a positioning pin 112 that fits into the positioning hole 111 may be provided in the other of the sensor board 22F and the insulator 34.

[0249] In this embodiment, the stator 24 and the sensor board 22F have a structure that prevents the sensor board 22F from being assembled upside down.

[0250] With the above configuration, it is possible to prevent the sensor board 22F from being erroneously assembled upside down when assembling the sensor board 22F. Since the worker does not need to pay attention to the front and back of the sensor board 22F, the efficiency of the assembly work is improved.

[0251] The structure for preventing the sensor board 22F from being assembled in a reversed state is not limited to the above. For example, the shape or position of the positioning pin 112 disposed inside the positioning hole 111 of the first arm portion 721 and the positioning pin 112 disposed inside the positioning hole 111 of the second arm portion 722 may be made different. Examples of making the shapes different include making the diameters of the positioning pins 112 different, making the outer shapes different, and the like. The difference in shape may prevent the positioning pin 112 of one arm portion 72 from being inserted into the positioning hole 111 of the other arm portion 72. In addition, the position of the positioning pin 112 may be asymmetrical with respect to the center line LC so that the position of the positioning hole 111 and the position of the positioning pin 112 do not match when the sensor board 22F is reversed. [Explanation of symbols]

[0252] 1...electric work machine, 2...housing, 3...rear cover, 4...gear case, 5...battery mounting section, 6...motor assembly, 7...power transmission mechanism, 8...spindle, 8C...chuck mechanism, 9...controller, 10...trigger switch, 11...forward / reverse switch lever, 12...speed switch lever, 13...mode change ring, 14...change ring, 15...light, 16...motor housing section, 17...grip section, 18...controller housing section, 19...battery pack, 20...motor, 21...fan, 22A...sensor board , 22B...sensor board, 22C...sensor board, 22D...sensor board, 22E...sensor board, 22F...sensor board, 23...rotor, 24...stator, 25...intake port, 26...exhaust port, 27...rotor core, 27F...end face, 27R...end face, 27S...outer surface, 28...rotor shaft, 29...permanent magnet, 30...magnet hole, 31...resin, 32...recess, 33...stator core, 34...insulator, 34F...front insulator, 34R...rear insulator, 35...coil, 35F...front end, 36...short circuit member, 37 ...Yoke portion, 37F...end face, 37R...end face, 38...teeth portion, 39...power terminal, 40...screw opening, 41...inner coil stopper portion, 42...outer coil stopper portion, 43...screw boss portion, 44...inner coil stopper portion, 45...outer coil stopper portion, 46...screw hole, 47...terminal support portion, 48...annular portion, 49...annular portion, 50...screw opening, 51...screw (second screw), 52...screw, 53...screw opening, 54...screw (first screw), 60...rotation sensor, 70...plate, 71...arc portion, 71A...opposing surface, 71B...reverse surface, 72...arc portion, 73...cover portion, 74...bridge portion, 75...outer arc portion, 80...signal line, 90...support member, 91...recess, 92...screw boss portion, 92R...end face, 93...screw opening, 94...support arc portion, 111...positioning hole, 112...positioning pin, 143...screw boss portion, 153...screw opening, 134...guide rib, 136...notch, 171...central portion, 172...one side convex portion, 173...the other side convex portion, 175...covering portion, 721...first arm portion, 722...second arm portion, 723...third arm portion, D1...distance, D2...distance.

Claims

1. A motor having a rotor that rotates around a rotation axis and a stator that is disposed around the rotor; a sensor substrate including a rotation sensor that detects rotation of the rotor and a plate that supports the rotation sensor; The stator includes: A stator core disposed around the rotor; an insulator fixed to the stator core; a plurality of coils fixed to the insulator and spaced apart in a circumferential direction; The plate is an arcuate portion disposed on a portion of the circumference of the rotary shaft and having an opposing surface opposing an end surface of the rotor in the axial direction; at least two arm portions protruding radially outward from the arc portion and fixed to the insulator; The rotation sensor is disposed on the opposing surface. Electric work equipment.

2. The arc portion is disposed radially inward from the coil. The electric operating machine according to claim 1.

3. an end of the arm portion on the radially outer side is disposed radially outward from the coil; An end of the arm portion is fixed to the insulator. The electric operating machine according to claim 2.

4. In the axial direction, the opposing surface is disposed at a position closer to a center of the coil than one end of the coil. The electric operating machine according to claim 2.

5. The arc portion has a reverse surface facing in a direction opposite to the opposing surface, In the axial direction, the reverse surface is disposed at a position closer to the center of the coil than one end of the coil. The electric operating machine according to claim 4.

6. The plate is a parallel plate. The electric operating machine according to claim 4 or 5.

7. The arm portion is disposed between a pair of adjacent coils. The electric operating machine according to claim 6.

8. The arm portion includes a first arm portion and a second arm portion, The first arm portion protrudes radially outward from one end of the arc portion in the circumferential direction, The second arm portion protrudes radially outward from the other end of the arc portion in the circumferential direction. The electric operating machine according to claim 7.

9. The plate is A bridge portion is provided connecting an end of the first arm portion and an end of the second arm portion on a radially outer side. The electric operating machine according to claim 8.

10. The bridge portion is an arc-shaped portion disposed around a portion of the rotation shaft. The electric operating machine according to claim 9.

11. a controller for controlling a drive current supplied to the coil based on a detection signal from the rotation sensor; a signal line connecting the rotation sensor and the controller; The signal line is supported by the bridge portion. The electric operating machine according to claim 9.

12. The arm portion includes a third arm portion, The third arm portion protrudes radially outward from a central portion of the arc portion in the circumferential direction. The electric operating machine according to claim 8.

13. a controller for controlling a drive current supplied to the coil based on a detection signal from the rotation sensor; a signal line connecting the rotation sensor and the controller; the signal line is supported by the third arm portion; The electric operating machine according to claim 12.

14. a power supply terminal through which the drive current flows; the third arm portion is disposed so as to overlap the power supply terminal in a plane perpendicular to the rotation axis. The electric operating machine according to claim 13.

15. At least one of the first arm portion, the second arm portion, and the third arm portion is fixed to the insulator by a screw. The electric operating machine according to claim 12.

16. The plate is a cover portion that connects a radially outer end of the first arm portion, an end of the second arm portion, and an end of the third arm portion; The electric operating machine according to claim 12.

17. a controller for controlling a drive current supplied to the coil based on a detection signal from the rotation sensor; a signal line connecting the rotation sensor and the controller; The signal line is supported by the cover portion.

17. An electric operating machine according to claim 16.

18. a power supply terminal through which the drive current flows; The cover portion is disposed so as to overlap the power supply terminal in a plane perpendicular to the rotation axis.

18. An electric operating machine according to claim 17.

19. a support member fixed to the insulator, At least two of the arm portions are fixed to the insulator via the support member. The electric operating machine according to claim 1.

20. The support member is a support arc portion fixed to the insulator by a first screw; a screw boss portion disposed radially inward from the support arc portion and to which the arm portion is fixed by a second screw; In the axial direction, an end face of the screw boss portion facing the same direction as the opposing surface is disposed at a position closer to the center of the coil than an end face of the stator core facing the opposite direction to the opposing surface.

20. The electric operating machine according to claim 19.

Images