Motor for electric working machine

Abstract

To provide a motor for an electric working machine capable of further increasing a flow rate of cooling air flowing through the motor.SOLUTION: A motor 20 for an electric working machine has a cylindrical stator 22. The motor 20 has a rotor 28 disposed on the inner circumferential side of the stator 22. The motor 20 has a sensor substrate 30 provided on the end portion in an axial direction of the stator 22. The sensor substrate 30 has a substrate body 31 that is disposed radially inward of the stator 22 as viewed from the axial direction. The sensor substrate 30 has legs 32 projecting radially outwardly from the substrate body 31 toward the stator 22. The stator 22 is exposed on at least one of the circumferential directions of the legs 32. The motor 20 has a sensor 35 provided on the legs 32 and facing the rotor 28 for detecting the rotation of the rotor 28.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a motor for an electric work machine, for example, provided in an electric work machine such as a chain saw. [Background technology]

[0002] For example, an electric work machine called a chain saw has a motor as a drive source as described in Patent Document 1. A so-called DC brushless motor is used for the motor. The brushless motor has a cylindrical stator and a rotor located radially inward of the stator and rotating integrally with the motor shaft. The brushless motor has a plurality of teeth protruding radially inward from the inner peripheral edge of the stator. A coil is wound around each tooth. The brushless motor has a sensor board on which a Hall IC is mounted as a sensor. The sensor board is a substantially disk-shaped board extending in a direction perpendicular to the motor axis direction at an opening of the cylindrical stator. The sensor board is arranged alongside the rotor in the motor axis direction. The Hall IC detects the rotation of the rotor.

[0003] A fan that generates cooling air is attached to the motor shaft. The cooling air generated by the rotation of the fan flows over the sensor board into the stator, cooling the coils wound around the teeth. The negative pressure generated by the cooling air flowing through the stator can also be used to cool, for example, the controller that controls the drive of the motor.

[0004] In conventional motors for electric work machines, the sensor board is provided in a disk shape that generally covers the opening of the cylindrical stator. In recent years, motor output has been set to be large in line with the trend toward higher power products. Therefore, when a conventional sensor board is attached to a stator, the wind tunnel resistance of the motor increases. As a result, the motor cannot be sufficiently cooled by the cooling air, and the temperature of the motor may increase. In addition, as the negative pressure of the cooling air that cools the motor decreases, the cooling air that cools the controller, etc. becomes weaker, and the temperature of the controller, etc. may increase. This may result in damage to the motor, controller, etc. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7025851 Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, there is a need for a motor for an electric work machine that can increase the flow rate of cooling air flowing through the motor. [Means for solving the problem]

[0007] According to one feature of the present disclosure, the motor for an electric work machine has a cylindrical stator. The motor for an electric work machine has a rotor arranged on the inner peripheral side of the stator. The motor for an electric work machine has a sensor board provided at an axial end of the stator. The sensor board has a board body located radially inward of the stator when viewed from the axial direction. The sensor board has legs that protrude radially outward from the board body toward the stator. The stator is exposed at least on one side of the legs in the circumferential direction. The motor for an electric work machine has a sensor that is provided on the legs and faces the rotor to detect rotation of the rotor.

[0008] Therefore, cooling air enters the stator from a portion where the stator is exposed on at least one side of the leg in the circumferential direction. This makes it possible to suppress wind tunnel resistance of the motor. Moreover, the sensor is provided on the leg protruding radially outward from the substrate body of the sensor substrate. The stator is exposed on at least one side of the leg in the circumferential direction. This makes it possible to expose the stator over a wide area along the inner peripheral wall of the stator while positioning the sensor at a position where it can detect the rotation of the rotor well. This makes it possible to flow cooling air along the inner peripheral wall of the stator, thereby increasing the flow rate of cooling air flowing through the motor. This makes it possible to suppress damage to the motor, etc., even when the motor output is increased. [Brief description of the drawings]

[0009] [Figure 1] 1 is a perspective view of an electric operating machine according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. [Figure 4] 4 is a left side view of the motor as viewed from a first direction side on which the sensor board is attached. FIG. [Diagram 5] 11 is a right side view of the stator to which the sensor board is attached, as viewed from a second direction opposite to the first direction. [Figure 6] 2 is a perspective view of the sensor unit as viewed from a first direction side. FIG. [Figure 7] 2 is a perspective view of the sensor unit with the mold removed, as viewed from the first direction side. FIG. [Figure 8] 11 is a perspective view of the sensor unit with the mold removed, as viewed from the second direction side. FIG. [Figure 9] 13 is a left side view of a stator to which a sensor board according to a second embodiment of the present disclosure is attached, as viewed from a first direction side. FIG. [Figure 10] 13 is a right side view of the stator to which the sensor board is attached, as viewed from the second direction side. FIG. [Figure 11] 10 is a cross-sectional view taken along line XI-XI in FIG. 8. [Figure 12] 2 is a perspective view of the sensor unit as viewed from a first direction side. FIG. [Figure 13] 11 is a perspective view of the sensor unit as viewed from the second direction side. FIG. [Figure 14] 11 is a left side view of a stator to which a sensor board of a conventional example is attached, as viewed from the first direction side. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] According to another feature of the present disclosure, the stator has a cylindrical outer cylinder portion. The stator has teeth that protrude radially inward from the outer cylinder portion and are wound with coils. The inner circumferential ends of the teeth are exposed when viewed from the axial direction. Therefore, the area of ​​the teeth that is exposed when viewed from the axial direction can be increased. This allows the coils wound around the teeth to be efficiently cooled with a larger amount of cooling air.

[0011] According to another feature of the present disclosure, the sensor board has mounting legs that protrude radially outward from the board body and are attached to the stator. By providing the mounting legs in a shape that protrudes radially outward from the board body, cooling air can be circumferentially adjacent to the mounting legs. This increases the flow rate of cooling air while improving the stability of the structure that supports the sensor board.

[0012] According to another feature of the present disclosure, the stator has a cylindrical outer cylinder portion. The stator has a plurality of teeth that protrude radially inward from the outer cylinder portion and are wound with coils. The legs and mounting legs are provided at positions that avoid the centers of the radial inner circumferential ends of the plurality of teeth when viewed from the axial direction. Therefore, the legs and mounting legs are disposed at positions that avoid the flow paths of cooling air that flows axially toward each tooth. Therefore, the coils wound around each tooth can be efficiently cooled by the cooling air. This can improve the cooling efficiency of the motor.

[0013] According to another feature of the present disclosure, the sensor board has at least one leg. The sensor board has at least one mounting leg. When viewed from the axial direction, all of the legs and all of the mounting legs avoid the centers of the inner peripheral ends of the multiple teeth, so that all of the centers of the inner peripheral ends of the multiple teeth are exposed. Therefore, when viewed from the axial direction, the centers of the inner peripheral ends of all of the teeth are exposed. Therefore, the sensor of the leg can be arranged at a position where the rotation of the rotor can be detected well, and the cooling efficiency of the motor can be further improved while increasing the stability of the support structure of the sensor board by the mounting leg.

[0014] According to another feature of the present disclosure, the motor for an electric work machine has an outer cylinder portion of a cylindrical stator. The motor for an electric work machine has a plurality of teeth protruding radially inward from the outer cylinder portion and wound with a coil. The motor for an electric work machine has a rotor arranged on the inner circumferential side of the plurality of teeth. The motor for an electric work machine has a sensor board provided at an axial end of the stator. The sensor board has an annular board body that is aligned along the radially inner side of the inner circumferential ends of the plurality of teeth when viewed from the axial direction. The center of at least one of the inner circumferential ends of the plurality of teeth is exposed radially outward from the board body. The motor for an electric work machine has a sensor that is provided on the sensor board and faces the rotor to detect rotation of the rotor.

[0015] Therefore, a gap is provided between the substrate body and the inner circumferential ends of the teeth in the radial direction. The exposed area of ​​the teeth can be increased by utilizing this gap. This makes it possible to suppress wind tunnel resistance of the motor. Furthermore, the center of the inner circumferential end of at least one of the teeth is exposed when viewed from the axial direction. This allows cooling air to flow near the center of the inner circumferential end of each tooth. This makes it possible to efficiently cool the coils wound around each tooth. Thus, damage to the motor, etc. can be suppressed even when the motor output is increased.

[0016] According to another feature of the present disclosure, the sensor board has legs protruding radially outward from the board body. The sensors are provided on the legs. Thus, the sensors can be arranged on the legs at positions where the rotor rotation can be detected well, while providing gaps between the legs and positions adjacent to each other in the circumferential direction. This allows the flow rate of cooling air flowing into the motor to be increased.

[0017] According to another feature of the present disclosure, the sensor board has at least one mounting leg that protrudes radially outward from the board body and is attached to the stator. The sensor board has at least one leg that protrudes radially outward from the board body and is provided with a sensor. When viewed from the axial direction, all of the legs and all of the mounting legs avoid the centers of the inner circumferential ends of the multiple teeth, so that all of the centers of the inner circumferential ends of the multiple teeth are exposed. Therefore, when viewed from the axial direction, the centers of the inner circumferential ends of all of the teeth are exposed. Therefore, all of the coils wound around each tooth can be efficiently cooled. This can further increase the cooling efficiency of the motor.

[0018] According to another feature of the present disclosure, the motor for an electric work machine has three sensors. The sensor board has three legs on which the sensors are mounted. Thus, by providing three sensors, the rotation of the rotor can be detected well. Moreover, by providing the three sensors on each leg, the gap between the legs and adjacent positions in the circumferential direction can be increased. Therefore, the flow rate of cooling air flowing into the motor can be increased.

[0019] According to another feature of the present disclosure, the motor for an electric work machine has a cylindrical stator. The motor for an electric work machine has a rotor arranged on the inner peripheral side of the stator. The motor for an electric work machine has a sensor board provided at an axial end of the stator. The sensor board has a board body located radially inward of the inner peripheral edge of the stator as viewed from the axial direction. The sensor board has an outer surface of the board body located opposite the rotor. The sensor board has an inclined surface on the outer surface of the board body that inclines radially outward toward the axially inward where the rotor is located. A gap is formed between the outer peripheral edge of the board body and the inner peripheral edge of the stator as viewed from the axial direction. The motor for an electric work machine has a sensor provided on the sensor board and facing the rotor to detect rotation of the rotor.

[0020] Therefore, an inclined surface is provided on the outer surface of the board body that is inclined toward the axial inside of the motor. This allows the cooling air flowing toward the board body to be guided by the inclined surface. This makes it possible to suppress the wind tunnel resistance of the motor. Furthermore, the inclined surface inclines toward the axial inside where the rotor is located as it moves radially outward. This makes it possible to guide the cooling air to flow along the inner peripheral edge of the stator, which is located radially outward of the inclined surface. In this way, the flow rate of the cooling air can be increased, thereby improving the cooling efficiency of the motor. This makes it possible to suppress damage to the motor, etc., even when the motor output is increased.

[0021] According to another feature of the present disclosure, the motor for an electric work machine has a mold that covers a surface of a base body. The inclined surface is formed by the shape of the outer surface of the base body or the shape of the mold. Therefore, even in the case of a base body covered with a mold, an inclined surface that guides cooling air can be provided on the outer surface to suppress wind tunnel resistance.

[0022] According to another feature of the present disclosure, the sensor board has mounting legs that protrude radially outward from the board body and are attached to the stator. The inclined surfaces are provided to avoid the mounting legs. Therefore, the inclined surfaces are provided at locations required for guiding cooling air, thereby improving cooling efficiency while maintaining the strength of the mounting legs.

[0023] According to another feature of the present disclosure, the sensor board has legs that protrude radially outward from the board body. The sensor is provided on the legs. Therefore, the sensor can be provided on the legs that are located in a position where the rotation of the rotor can be detected well and where the cooling air guided into the motor by the inclined surface of the board body is not obstructed. This makes it possible to suppress wind tunnel resistance and improve the cooling efficiency of the motor.

[0024] According to another feature of the present disclosure, the inclined surface is inclined in the radial direction over the entire surface from the inner peripheral edge to the outer peripheral edge of the board body. Therefore, the cooling air flowing in the axial direction toward the board body can be smoothly guided to flow radially outward of the board body. This makes it possible to suppress wind tunnel resistance in the board body. This makes it possible to improve the cooling efficiency of the motor.

[0025] Next, a first embodiment of the present disclosure will be described with reference to Figs. 1 to 8. As an example of an electric working machine 1, a chain saw in which a saw chain 3 is driven by motor output will be illustrated. In the following description, the direction in which a guide bar 2 supporting the saw chain 3 protrudes is defined as the forward direction. A user holds the electric working machine 1 while positioned behind the electric working machine 1 (the far right side in Fig. 1). The up, down, left and right directions are based on the directions as seen by the user. In the following description, the left direction is also referred to as the first direction, and the right direction is also referred to as the second direction.

[0026] As shown in FIG 1, the electric work machine 1 has a work machine body 10 housed in a main body housing 11. A guide bar 2 protrudes forward from the front end of the main body housing 11. A saw chain 3 is attached along the outer periphery of the guide bar 2. The saw chain 3 is guided so as to move circumferentially around the outer periphery of the guide bar 2. The saw chain 3 is driven by the output of a motor 20 provided in the work machine body 10.

[0027] As shown in FIG. 1, the electric working machine 1 has a front grip 4. The front grip 4 is formed in a loop shape at the front of the main body housing 11. The front grip 4 extends upward from the lower end of the left side surface of the main body housing 11, extends to the right above the main body housing 11, and is connected to the upper end of the right side surface of the main body housing 11. The electric working machine 1 has a hand guard 5. The hand guard 5 is provided in front of the upper part of the front grip 4. The hand guard 5 extends upward from the upper end of the front part of the main body housing 11. The hand guard 5 protects the hands of a user holding the front grip 4.

[0028] As shown in FIG. 1, the electric work machine 1 has a rear grip 6 at the rear of the work machine body 10. The rear grip 6 is formed in a loop shape extending rearward from the rear end of the body housing 11. A trigger lock lever 7 that can be pushed by the hand holding the rear grip 6 is provided at the top of the rear grip 6. A trigger 8 that can be pulled by the fingers of the hand holding the rear grip 6 is provided on the inner periphery of the loop shape of the rear grip 6. A user holds the rear grip 6 and presses the trigger lock lever 7. In this state, the trigger 8 can be pulled with the fingers. By pulling the trigger 8 with the fingers, a drive current is supplied to the motor 20 and the motor 20 is driven. When the trigger lock lever 7 is not operated, pulling the trigger 8 is restricted.

[0029] As shown in FIG. 1, the work machine body 10 is provided with a battery mounting section 12 in which a rechargeable battery 13 can be removably mounted. The battery mounting section 12 is recessed in the upper surface of the work machine body 10. The battery 13 can be mounted in the battery mounting section 12 by sliding it from top to bottom. The battery 13 can be removed from the battery mounting section 12 by sliding it from bottom to top in the opposite direction to the mounting direction. A motor 20, which will be described later, is driven by a drive current supplied from the battery 13 mounted in the battery mounting section 12. The battery 13 is, for example, a lithium-ion battery with an output voltage of 40V. The battery 13 can be removed from the battery mounting section 12 and repeatedly charged using a separately prepared charger. The battery 13 can be used as a power source between other electric work machines, such as a screwdriver or an electric drill.

[0030] As shown in FIGS. 1 and 2, the main housing 11 accommodates a motor 20 for an electric work machine. The motor 20 is disposed in front of the battery mounting portion 12 and below the front grip 4. The motor 20 is accommodated in a substantially cylindrical motor case 21 with a motor shaft 27 extending in the left-right direction. The axial direction of the motor shaft 27 is parallel to the left-right direction. Bearings 27a and 27b are attached to the inside of the motor case 21. The motor shaft 27 is supported by the bearings 27a and 27b so as to be rotatable around a motor axis J extending in the left-right direction. The right end of the motor shaft 27 protrudes from the motor case 21. A sprocket 29 for transmitting power to the saw chain 3 is attached to the right end of the motor shaft 27. The saw chain 3 is driven via the sprocket 29 by the rotation of the motor shaft 27 around the motor axis J.

[0031] As shown in FIG. 2, the main housing 11 accommodates the controller 14. The controller 14 is provided in a shallow rectangular box-shaped case with a circuit board accommodated therein. The controller 14 is disposed above the motor case 21 in a position extending in a substantially horizontal direction with the vertical direction being the thickness direction. The controller 14 outputs a signal for controlling the electric operating machine 1. The controller 14 supplies a drive current from the battery 13 to the motor 20 when a trigger 8 (see FIG. 1) is pulled. The controller 14 receives a signal detecting the rotation of the rotor 28 from a sensor 35, which will be described later. The detected rotation of the rotor 28 includes the rotation position or the rotation speed of the rotor 28, or includes both. The controller 14 controls the drive current supplied to the motor 20 in accordance with the rotation of the rotor 28.

[0032] As shown in FIGS. 2 and 3, the motor 20 is an inner rotor type DC brushless motor. The motor 20 has a cylindrical stator 22. The stator 22 is housed in a motor case 21. A rotor 28 is provided on the inner periphery of the stator 22. The rotor 28 is attached integrally to a motor shaft 27. The rotor 28 is rotatable around the motor axis J relative to the stator 22. A cooling fan 15 is attached integrally to the motor shaft 27. The cooling fan 15 is a centrifugal fan. The cooling fan 15 is provided to the right of the right end of the stator 22 and to the left of the right bearing 27b. The cooling fan 15 rotates integrally with the motor shaft 27 to generate cooling air inside the motor case 21 that flows in the axial direction from left to right. The cooling air that flows to the cooling fan 15 is sent radially outward by the cooling fan 15.

[0033] As shown in FIGS. 1 and 2, an intake port 11a is provided on the left side surface of the main housing 11. The intake port 11a is located to the left of the motor 20. The intake port 11a is provided to penetrate the main housing 11 in the left-right direction. When the cooling fan 15 rotates, outside air is introduced into the main housing 11 from the intake port 11a. An exhaust port 11b is provided on the bottom surface of the main housing 11. The exhaust port 11b is located radially outward from the cooling fan 15. The cooling air sent radially outward by the cooling fan 15 is exhausted to the outside of the main housing 11 from the exhaust port 11b.

[0034] As shown in Fig. 2, the rotor 28 has a rotor core 28b including a plurality of laminated steel plates. The rotor core 28b is disposed so as to surround the motor shaft 27 on the inner periphery side of the stator 22. The rotor 28 has a plurality of magnets 28c. The magnets 28c are permanent magnets. The magnets 28c are disposed inside the rotor core 28b. The plurality of magnets 28c are lined up in the circumferential direction so as to surround the motor shaft 27. In this embodiment, eight magnets 28c are provided.

[0035] 2 and 3, the stator 22 has a first end 22a at its left end (first direction). The stator 22 has a second end 22b at its right end (second direction) opposite to the first direction. The outer periphery of the stator 22 is covered by an outer tube portion 23 having a substantially cylindrical shape. The stator 22 has a stator core 22d including a plurality of laminated steel plates. The stator core 22d is disposed along the inner periphery of the outer tube portion 23.

[0036] As shown in Figures 2 and 4, the stator 22 has a plurality of teeth 24 protruding radially inward from the outer cylinder portion 23. The plurality of teeth 24 are provided at equal intervals in the circumferential direction. In this embodiment, twelve teeth 24 are provided. The plurality of teeth 24 are provided at 30° intervals in the circumferential direction centered on the motor axis J. An inner peripheral end 24a of each tooth 24 is located slightly radially outward from an outer peripheral edge 28a of the rotor 28. A coil 25 is wound around each tooth 24. A driving current is supplied to each coil 25 from the battery 13 via the controller 14 (see Figure 1).

[0037] 3 and 4, a substantially annular insulator 26 is integrally attached to the end of the stator 22 in the first direction. The insulator 26 is made of an insulating material such as synthetic resin. The insulator 26 is fixed to the stator core 22d by insert molding. The end face of the insulator 26 in the first direction corresponds to the first end 22a of the stator 22 in this disclosure. The inner peripheral edge 26a of the insulator 26 is located radially inward from the inner peripheral edge of the outer cylinder portion 23. The inner peripheral edge 26a of the insulator 26 corresponds to the inner peripheral edge 22c of the stator 22 in this disclosure.

[0038] As shown in Figures 3 and 4, the insulator 26 has a connection portion 26b that protrudes radially outward. The connection portion 26b electrically connects the coil 25 and a sensor 35, which will be described later, to the controller 14 and the battery 13 (see Figure 1). The insulator 26 has a board connecting portion 26c to which a sensor board 30, which will be described later, can be attached. The board connecting portion 26c protrudes radially inward from an inner peripheral edge 26a of the insulator 26. In this embodiment, five board connecting portions 26c are provided. The board connecting portions 26c are provided at intervals of approximately 60° in the circumferential direction around the motor axis J. No board connecting portion 26c is provided on the inner peripheral side of the location where the connection portion 26b is provided.

[0039] As shown in FIGS. 3 to 5, the motor 20 has a plurality of sensors 35. The sensors 35 are magnetic sensors that detect the magnets 28c (see FIG. 2) of the rotor 28, and are, for example, Hall ICs. The sensors 35 detect the magnets 28c, thereby detecting the rotation of the rotor 28. The plurality of sensors 35 are provided on a plate-shaped sensor substrate 30. In this embodiment, three sensors 35 are provided. The three sensors 35 are provided at intervals of 60° in the circumferential direction centered on the motor axis J. The sensor substrate 30 is disposed in the first direction relative to the rotor 28. The sensor substrate 30 is integrally attached to and supported by the insulator 26. The sensor substrate 30 and the three sensors 35 constitute a sensor unit. The sensor unit includes a mold 34, a diode 36, a signal line 37, a pattern 39, and the like, which will be described later.

[0040] As shown in Figs. 3 to 6, the sensor board 30 is provided by processing a flat board material. The sensor board 30 is provided from a board material, for example, glass fiber impregnated with epoxy resin and heat-cured. The sensor board 30 has an annular board body 31 with a circular through hole formed in the center. An inner peripheral edge 31b of the board body 31 corresponds to the side surface of the circular through hole. The motor shaft 27 is inserted into the inner peripheral side of the inner peripheral edge 31b of the board body 31.

[0041] As shown in FIGS. 3 to 8, the sensor board 30 has a plurality of legs 32 that protrude radially outward from the outer peripheral edge 31a of the board body 31. In this embodiment, four legs 32 are provided. Each of the three legs 32 is provided with a sensor 35. The sensor 35 is provided on an inner surface 30b on the second direction side of the leg 32 and faces the magnet 28c. A signal line 37 extends radially outward from one of the legs 32. The signal line 37 is electrically connected to the connection portion 26b of the insulator 26. The sensor 35 is electrically connected to the controller 14 (see FIG. 2) via the signal line 37.

[0042] 5 and 8, the sensor unit has a plurality of diodes 36. Each diode 36 is provided near and electrically connected to each sensor 35 on the sensor substrate 30. In this embodiment, three diodes 36 are provided. The diodes 36 are provided on the inner surface 30b on the second direction side of the substrate main body 31.

[0043] As shown in FIGS. 5, 7, and 8, a pattern 39 is provided on the surface of the sensor substrate 30. The pattern 39 electrically connects the sensor 35, the diode 36, and the signal line 37. An inner pattern 39a provided on the inner surface 30b of the sensor substrate 30 includes an arc-shaped portion extending in the circumferential direction of the substrate body 31. The inner pattern 39a further extends from the arc-shaped portion of the substrate body 31 toward the sensor 35 or the signal line 37 of each leg 32. An outer pattern 39b is provided on the outer surface 30a of the sensor substrate 30 in the first direction. Similarly, the outer pattern 39b includes an arc-shaped portion extending in the circumferential direction of the substrate body 31 and a portion extending from the arc-shaped portion toward the sensor 35 or the signal line 37 of each leg 32.

[0044] 3 to 8, the sensor board 30 has a plurality of mounting legs 33 that protrude radially outward from the outer peripheral edge 31a of the board body 31. In this embodiment, five mounting legs 33 are provided. Each mounting leg 33 is attached to the board connecting portion 26c of the insulator 26 by, for example, a screw or the like. A circumferential gap is provided between the mounting legs 33 or between the mounting legs 33 and the leg portion 32. A slit 38 is formed in this circumferential gap to allow air to be introduced from the outside of the sensor board 30 toward the inside of the motor 20.

[0045] As shown in Figs. 4 and 6, the sensor unit has a resin mold 34 that covers the outer surface 30a on the first direction side and the inner surface 30b on the second direction side. The mold 34 is provided on the substrate body 31 and the leg 32. The mold 34 is not provided on the mounting leg 33. By not providing the mold 34 on the mounting leg 33, it becomes easier to fasten the mounting leg 33 and the substrate connecting portion 26c by screwing. The mold 34 does not cover the outer peripheral edge 31a of the substrate body 31 or the circumferential end surface of the leg 32. This makes it possible to prevent the opening area of ​​the slit 38 from being narrowed by the mold 34. Note that the mold 34 is omitted from Figs. 5, 7, and 8 for the sake of explanation.

[0046] As shown in Figs. 2, 4, and 5, the slits 38 are provided between the inner peripheral edge 22c of the stator 22 and the outer peripheral edge 31a of the substrate body 31 in the radial direction. The slits 38 are provided between the mounting legs 33 in the circumferential direction, or between the mounting legs 33 and the leg portions 32 in the circumferential direction. When viewed from the first direction side, the inner peripheral edge 22c of the stator 22 is exposed on both circumferential sides of the leg portions 32. When viewed from the first direction side, the inner peripheral edge 22c of the stator 22 is exposed on both circumferential sides of the mounting legs 33. The outer peripheral edge 31a of the substrate body 31 is located radially inward from the center of the inner peripheral end 24a of the teeth 24. When viewed from the first direction side, the centers of the inner peripheral ends 24a of all the teeth 24 are exposed from the slits 38. In other words, all the legs 32 and the mounting legs 33 are disposed at positions that avoid the centers of the inner peripheral ends 24a of the teeth 24 when viewed from the first direction side.

[0047] The cooling air generated by the rotation of the cooling fan 15 flows through the slits 38 toward the inside of the stator 22. By passing through the slits 38, the wind tunnel resistance of the motor 20 is suppressed. Therefore, the cooling air can be sufficiently applied to the coils 25 wound around each tooth 24 to cool them. The cooling air that passes through the slits 38 can cool not only the coils 25, but also, for example, the sensor 35 provided on the sensor board 30. The cooling air that has cooled the motor 20 flows to the cooling fan 15 and is discharged from the exhaust port 11b.

[0048] As described above, the motor 20 for an electric work machine has a cylindrical stator 22 as shown in Figs. 3 to 5. The motor 20 has a rotor 28 arranged on the inner periphery side of the stator 22. The motor 20 has a sensor board 30 provided at an end of the stator 22 in the axial direction. The sensor board 30 has a board body 31 located radially inward of the stator 22 when viewed from the axial direction. The sensor board 30 has legs 32 protruding radially outward from the board body 31 toward the stator 22. The stator 22 is exposed at least on one side of the legs 32 in the circumferential direction. The motor 20 has a sensor 35 provided on the legs 32 and facing the rotor 28 to detect rotation of the rotor 28.

[0049] Therefore, the cooling air enters the stator 22 from a portion where the stator 22 is exposed on at least one side of the leg 32 in the circumferential direction. Therefore, the wind tunnel resistance of the motor 20 can be suppressed. Moreover, the sensor 35 is provided on the leg 32 protruding radially outward from the board body 31 of the sensor board 30. The stator 22 is exposed on at least one side of the leg 32 in the circumferential direction. Therefore, the stator 22 can be exposed in a wide area along the inner peripheral edge 22c of the stator 22 while the sensor 35 is disposed at a position where the rotation of the rotor 28 can be detected well. This allows the cooling air to flow along the inner peripheral edge 22c of the stator 22, and the flow rate of the cooling air flowing through the motor 20 can be increased. This allows the motor 20 and the like to be prevented from being damaged even when the output of the motor 20 is increased.

[0050] 2 to 5, the stator 22 has a cylindrical outer cylinder portion 23. The stator 22 has teeth 24 that protrude radially inward from the outer cylinder portion 23 and around which coils 25 are wound. Inner circumferential ends 24a of the teeth 24 are exposed when viewed from the axial direction. This makes it possible to increase the area of ​​the teeth 24 that is exposed when viewed from the axial direction. This allows the coils 25 wound around the teeth 24 to be efficiently cooled with a larger amount of cooling air.

[0051] 3 and 4, the sensor board 30 has mounting legs 33 that protrude radially outward from the board body 31 and are attached to the stator 22. By providing the mounting legs 33 in a shape that protrudes radially outward from the board body 31, it is possible to allow cooling air to flow to an area circumferentially adjacent to the mounting legs 33. This makes it possible to increase the flow rate of cooling air while improving the stability of the structure that supports the sensor board 30.

[0052] As shown in Figs. 2 to 5, the stator 22 has a cylindrical outer cylinder portion 23. The stator 22 has a plurality of teeth 24 that protrude radially inward from the outer cylinder portion 23 and on which coils 25 are wound. The legs 32 and the mounting legs 33 are provided at positions that avoid the centers of the radial inner circumferential ends 24a of the plurality of teeth 24 when viewed from the axial direction. Therefore, the legs 32 and the mounting legs 33 are disposed at positions that avoid the flow paths of the cooling air that flows axially toward each tooth 24. Therefore, the coils 25 wound around each tooth 24 can be efficiently cooled by the cooling air. This can improve the cooling efficiency of the motor 20.

[0053] 4 and 5, the sensor board 30 has at least one leg 32. The sensor board 30 has at least one mounting leg 33. When viewed from the axial direction, all of the legs 32 and all of the mounting legs 33 avoid the centers of the inner circumferential ends 24a of the multiple teeth 24, so that all of the centers of the inner circumferential ends 24a of the multiple teeth 24 are exposed. Therefore, when viewed from the axial direction, the centers of the inner circumferential ends 24a of all of the teeth 24 are exposed. Therefore, the sensor 35 of the leg 32 can be disposed at a position where the rotation of the rotor 28 can be detected satisfactorily, and the cooling efficiency of the motor 20 can be further improved while increasing the stability of the support structure of the sensor board 30 by the mounting leg 33.

[0054] As shown in FIGS. 2 to 5, the motor 20 has an outer cylinder portion 23 of a cylindrical stator 22. The motor 20 has a plurality of teeth 24 that protrude radially inward from the outer cylinder portion 23 and are wound with coils 25. The motor 20 has a rotor 28 that is disposed on the inner periphery side of the plurality of teeth 24. The motor 20 has a sensor board 30 that is provided at an end of the stator 22 in the axial direction. The sensor board 30 has a board body 31 that is annular and that is aligned along the radial inside of the inner periphery ends 24a of the plurality of teeth 24 when viewed from the axial direction. The center of at least one of the inner periphery ends 24a of the plurality of teeth 24 is exposed radially outward from the board body 31. The motor 20 has a sensor 35 that is provided on the sensor board 30 and faces the rotor 28 to detect rotation of the rotor 28.

[0055] Therefore, a gap is provided between the substrate body 31 and the inner circumferential ends 24a of the teeth 24 in the radial direction. The exposed area of ​​the teeth 24 can be increased by utilizing the gap. This makes it possible to suppress the wind tunnel resistance of the motor 20 to the cooling air. Furthermore, the center of at least one of the inner circumferential ends 24a of the teeth 24 is exposed when viewed from the axial direction. This makes it possible to flow the cooling air near the center of the inner circumferential end 24a of each tooth 24. This makes it possible to efficiently cool the coils 25 wound around each tooth 24. Thus, even when the output of the motor 20 is increased, damage to the motor 20, etc. can be suppressed.

[0056] 4 to 8, the sensor board 30 has legs 32 that protrude radially outward from a board body 31. A sensor 35 is provided on the legs 32. Therefore, the sensor 35 can be disposed on the legs 32 at a position where it can satisfactorily detect the rotation of the rotor 28, while a gap can be provided at a position adjacent to the legs 32 in the circumferential direction. This makes it possible to increase the flow rate of cooling air flowing into the motor 20.

[0057] As shown in Figs. 4 and 5, the sensor board 30 has at least one mounting leg 33 that protrudes radially outward from the board body 31 and is attached to the stator 22. The sensor board 30 has at least one leg 32 that protrudes radially outward from the board body 31 and is provided with a sensor 35. When viewed from the axial direction, all of the legs 32 and all of the mounting legs 33 avoid the centers of the inner circumferential ends 24a of the multiple teeth 24, so that all of the centers of the inner circumferential ends 24a of the multiple teeth 24 are exposed. Therefore, when viewed from the axial direction, the centers of the inner circumferential ends 24a of all the teeth 24 are exposed. Therefore, all of the coils 25 wound around each tooth 24 can be efficiently cooled. This can further improve the cooling efficiency of the motor 20.

[0058] As shown in Figures 4 to 8, the motor 20 has three sensors 35. The sensor board 30 has three legs 32 on which the sensors 35 are provided. Therefore, by providing the three sensors 35, the rotation of the rotor 28 can be detected well. Furthermore, by providing the three sensors 35 on each of the legs 32, the gap between each of the legs 32 and adjacent positions in the circumferential direction can be increased. Therefore, the flow rate of cooling air flowing into the motor 20 can be increased.

[0059] Next, a second embodiment of the present disclosure will be described with reference to Figures 9 to 13. A motor 40 for an electric work machine in the second embodiment has a sensor board 41 instead of the sensor board 30 shown in Figure 6. In the following explanation, only the parts that differ from the first embodiment will be described in detail.

[0060] As shown in FIGS. 9 to 13, the motor 40 has three sensors 35 provided on a sensor board 41. The sensor board 41 and the three sensors 35 constitute a sensor unit. The sensor unit includes a mold, a diode 36, a signal line, a pattern 48 described later, and the like. The sensor board 41 is disposed on the first direction side with respect to the rotor 28. The sensor board 41 is integrally attached to and supported by the insulator 26. The sensor board 41 is a three-dimensional molded part made of synthetic resin, called an MID (Molded Interconnect Device). The sensor board 41 has an annular board body 42 with a circular through hole formed in the center. An inner peripheral edge 42b of the board body 42 corresponds to the side surface of the circular through hole, and the motor shaft 27 is inserted into the inner peripheral side.

[0061] As shown in FIGS. 9 to 13, the sensor board 41 has a plurality of legs 43 that protrude radially outward from the outer peripheral edge 42a of the board body 42. In this embodiment, three legs 43 are provided. Each of the three legs 43 is provided with a sensor 35. The sensor 35 is provided on an inner surface 41b on the second direction side of the leg 43 and faces the magnet 28c (see FIG. 2). One of the legs 43 is provided in a rectangular shape that is long in the circumferential direction. A signal line 37 extends radially outward from the rectangular leg 43. The sensor unit has three diodes 36. Each diode 36 is provided on the inner surface 41b of the board body 42.

[0062] 10, 12, and 13, a pattern 48 is provided on the surface of the sensor substrate 41. The pattern 48 electrically connects the sensor 35, the diode 36, and the signal line 37. The inner pattern 48a provided on the inner surface 41b of the sensor substrate 41 includes an arc-shaped portion extending in the circumferential direction of the substrate body 42, and a portion extending further from the arc-shaped portion toward the sensor 35 or the signal line 37 of each leg 43. An outer pattern 48b is provided on the outer surface 41a on the first direction side of the sensor substrate 41. The outer pattern 48b similarly includes an arc-shaped portion extending in the circumferential direction of the substrate body 42, and a portion extending from the arc-shaped portion toward the sensor 35 or the signal line 37 of each leg 43.

[0063] As shown in FIGS. 9 to 13, the sensor board 41 has a plurality of mounting legs 44 that protrude radially outward from the outer peripheral edge 42a of the board body 42. In this embodiment, three mounting legs 44 are provided. Each mounting leg 44 is attached to the board connecting portion 26c of the insulator 26 by, for example, a screw or the like. The mounting legs 44 are located on the first direction side of the inner surface 41b of the sensor board 41 on which the sensor 35 is provided. Therefore, compared to the first embodiment, the screw fastening position can be arranged at a position farther away from the rotor 28 than the sensor 35. By providing the sensor board 41 in the MID in this manner, the arrangement of the sensor 35, the arrangement of the screw fastening position, the thickness of the board body 42, and the like can be set with a high degree of freedom. A circumferential gap is provided between the mounting legs 44 or between the mounting legs 44 and the leg portion 43. A slit 47 is formed in this circumferential gap to introduce air from the outside of the sensor board 41 toward the inside of the motor 40.

[0064] As shown in FIGS. 12 and 13, an inclined surface 46 inclined with respect to the radial direction is provided on the outer side surface 41a of the sensor board 41 on the first direction side. The inclined surface 46 is provided on the board body 42 and the leg portion 43. The inclined surface 46 is formed to avoid the mounting leg 44, and is not provided on the mounting leg 44. The inclined surface 46 inclines in the second direction axially inward toward the radially outward slit 47. The inclined surface 46 is provided on the board body 42 at approximately the same inclination angle over the entire surface from the inner peripheral edge 42b to the outer peripheral edge 42a. The inclined surface 46 is provided on the leg portion 43 at approximately the same inclination angle over the entire surface from the inner peripheral edge 42b to the outer peripheral edge, which is the same as that of the board body 42. In this embodiment, the resin mold covering the outer side surface 41a and the inner side surface 41b of the sensor board 41 is omitted from the illustration. The mold is provided on the board body 42 and the leg portion 43, but not on the mounting leg 44. The outer surface of the mold is provided approximately parallel to the inclined surface 46 and inclined toward the slit 47 radially outward.

[0065] As shown in Figs. 9 and 10, the slits 47 are provided between the inner peripheral edge 22c of the stator 22 and the outer peripheral edge 42a of the substrate body 42 in the radial direction. The slits 47 are provided between the mounting legs 44 in the circumferential direction, or between the mounting legs 44 and the leg portion 43 in the circumferential direction. When viewed from the first direction side, the inner peripheral edge 22c of the stator 22 is exposed on both circumferential sides of the leg portion 43. When viewed from the first direction side, the inner peripheral edge 22c of the stator 22 is exposed on both circumferential sides of the mounting legs 44. The outer peripheral edge 42a of the substrate body 42 is located radially inward from the center of the inner peripheral end 24a of the tooth 24. When viewed from the first direction side, the inner peripheral ends 24a of all the teeth 24 are exposed from the slits 47. With respect to the ten teeth 24 excluding the two teeth 24 overlapping with the rectangular leg portion 43 long in the circumferential direction, the centers of the inner circumferential ends 24a are exposed from the slits 47 when viewed from the first direction side.

[0066] As described above, the motor 40 for an electric work machine has a cylindrical stator 22 as shown in Figs. 9 to 11. The motor 40 has a rotor 28 arranged on the inner circumferential side of the stator 22. The motor 40 has a sensor board 41 provided at an end of the stator 22 in the axial direction. The sensor board 41 has a board body 42 located radially inward of the inner circumferential edge 22c of the stator 22 as viewed from the axial direction. The sensor board 41 has an outer surface 41a of the board body 42 located on the opposite side of the rotor 28. The sensor board 41 has an inclined surface 46 on the outer surface 41a of the board body 42 that inclines radially outward toward the axially inner side (second direction side) where the rotor 28 is located. A gap (slit 47) is formed between the outer circumferential edge 42a of the board body 42 and the inner circumferential edge 22c of the stator 22 as viewed from the axial direction. The motor 40 has a sensor 35 provided on the sensor board 41 and facing the rotor 28 to detect the rotation of the rotor 28.

[0067] Therefore, an inclined surface 46 is provided on the outer side surface 41a of the substrate body 42, inclined toward the axial inside of the motor 40. This allows the cooling air flowing toward the substrate body 42 to be guided by the inclined surface 46. This allows the wind tunnel resistance of the motor 40 to be suppressed. Moreover, the inclined surface 46 inclines toward the axial inside where the rotor 28 is located as it moves radially outward. This allows the cooling air to be guided to flow along the inner peripheral edge 22c of the stator 22 located radially outward of the inclined surface 46. This allows the flow rate of the cooling air to be increased, thereby improving the cooling efficiency of the motor 40. This allows damage to the motor 40, etc. to be suppressed even when the output of the motor 40 is increased.

[0068] 12 and 13, the motor 40 has a mold that covers the surface of the board body 42. The inclined surface 46 is formed by the shape of the outer side surface 41a of the board body 42 or the shape of the mold. Therefore, even in the board body 42 covered with a mold, the inclined surface 46 that guides the cooling air can be provided on the outer side surface 41a to suppress wind tunnel resistance.

[0069] 12 and 13, the sensor board 41 has mounting legs 44 that protrude radially outward from the board body 42 and are attached to the stator 22. The inclined surfaces 46 are provided to avoid the mounting legs 44. Therefore, by providing the inclined surfaces 46 at locations required for guiding the cooling air, the strength of the mounting legs 44 can be maintained while improving the cooling efficiency.

[0070] 9 to 13, the sensor board 41 has legs 43 that protrude radially outward from the board body 42. The sensor 35 is provided on the legs 43. The sensor 35 can therefore be provided on the legs 43, which are located in a position where the rotation of the rotor 28 can be detected satisfactorily and where the cooling air guided into the motor 40 by the inclined surface 46 of the board body 42 is not obstructed. This makes it possible to suppress wind tunnel resistance and improve the cooling efficiency of the motor 40.

[0071] 9 and 12, the inclined surface 46 is inclined in the radial direction over the entire surface from the inner peripheral edge 42b to the outer peripheral edge 42a of the board body 42. Therefore, the cooling air flowing in the axial direction toward the board body 42 can be smoothly guided so as to flow radially outward of the board body 42. This makes it possible to suppress wind tunnel resistance in the board body 42. This makes it possible to improve the cooling efficiency of the motor 40.

[0072] FIG. 14 shows a conventional motor 50 for an electric work machine for comparison with each embodiment of the present disclosure. A sensor board 51 provided in the conventional motor 50 has a disk-shaped board body 52. ​​A plurality of sensors 35 are provided on the inner surface of the board body 52. ​​The outer and inner surfaces of the board body 52 are covered with a mold 53. The board body 52 is connected to each board connection portion 26c of the insulator 26 near the outer circumferential edge 52a. Therefore, only a small gap is provided in the radial direction between the outer circumferential edge 52a of the board body 52 and the inner circumferential edge 22c of the stator 22. Most of the teeth 24 are not exposed when viewed from the axial direction, and only a part of the teeth 24 is visible in the area where the signal line 37 is arranged. Thus, the conventional motor 50 has fewer gaps through which cooling air passes into the stator 22 compared to the first and second embodiments of the present disclosure, and has a large wind tunnel resistance.

[0073] The motors 20, 40 for electric work machines of the present embodiment described above can be modified as appropriate. The motors 20, 40 installed in a chainsaw have been exemplified. Instead, the motors can be applied to various electric work machines, such as screwdrivers, electric drills, circular saws, grinders, cleaners, blowers, etc. The number of teeth 24 and the number of magnets 28c installed in the rotor 28 are not limited to the exemplified numbers and may be modified as appropriate.

[0074] A configuration in which three sensors 35 for detecting rotation of rotor 28 are provided has been exemplified. Alternatively, for example, a configuration in which one sensor 35 is provided may be used. A configuration in which one sensor 35 is provided on each of leg portions 32, 43 has been exemplified. Alternatively, for example, multiple sensors 35 may be provided on each of leg portions 32, 43. The configuration of this embodiment is more preferable in that the total opening area of ​​slits 38, 47 can be made larger.

[0075] The substrate bodies 31, 42 are illustrated as being annular. Alternatively, for example, they may be C-shaped extending in the circumferential direction of the motor shaft 27. The substrate bodies 31, 42 are illustrated as having circular outer peripheries 31a, 42a. Alternatively, for example, the outer peripheries 31a, 42a may be polygonal. The diode 36 provided on the substrate bodies 31, 42 is illustrated. Alternatively, the diode 36 may be provided on the legs 32, 43.

[0076] In the illustrated embodiment, the slits 38, 47 are provided on both circumferential sides of the legs 32, 43. Alternatively, the slits 38, 47 may be provided on only one circumferential side of the legs 32, 43. In the illustrated embodiment, the legs 32, 43 and the mounting legs 33, 44 are separate parts. Alternatively, the legs and the mounting legs may be the same part. The number of mounting legs may be three or more as long as the sensor board can be stably supported. The number of mounting legs may be three or five as illustrated, or may be four or six or more.

[0077] In the illustrated embodiment, the centers of the inner circumferential ends 24a of all of the teeth 24 are exposed from the slits 38 when viewed from the axial direction. Alternatively, the centers of the inner circumferential ends 24a of some of the teeth 24 may be exposed from the slits 38. The more exposed the teeth are, the more the wind tunnel resistance can be suppressed.

[0078] In the illustrated configuration, the inclined surface 46 is provided on the outer side surface 41a of both the substrate body 42 and the leg portion 43. Alternatively, for example, the inclined surface 46 may be provided on the outer side surface 41a of either the substrate body 42 or the leg portion 43. For example, the inclined surface 46 may be provided on the outer side surface 41a of the substrate body 42 and some of the multiple leg portions 43.

[0079] In the illustrated configuration, the sensor substrate 41 is provided as an MID, and a mold extending approximately parallel to the inclined surface 46 is provided on the outer surface 41a of the substrate body 42 and the leg portion 43. Alternatively, the sensor substrate 41 may be provided from a flat plate-shaped material similar to the sensor substrate 30, and an inclined surface may be formed on the outer surface of the mold. This configuration can be achieved, for example, by making the outer surface of the mold 34 shown in FIG. 6 into an inclined surface.

[0080] The shapes of the patterns 39, 48 provided on the sensor substrates 30, 41 are not limited to those illustrated and may be changed as appropriate. For example, the patterns 39, 48 may be provided only on the outer surfaces 30a, 41a or only on the inner surfaces 30b, 41b of the sensor substrates 30, 41. The patterns 39, 48 are illustrated as having a greater number of inner patterns 39a, 48a than outer patterns 39b, 48b. Alternatively, the outer patterns 39b, 48b may have a greater number of inner patterns than the inner patterns 39a, 48a. The sensor substrates 30, 41 may be provided with a capacitor or the like electrically connected to each sensor 35. [Explanation of symbols]

[0081] 1...Electric working machine 2. Guide bar 3. Saw chain 4. Front grip 5. Handguard 6…Rear grip 7...Trigger lock lever 8...Trigger 10...Work machine body 11...main body housing, 11a...air intake, 11b...air exhaust 12…Battery mounting section 13…Battery 14…Controller 15…Cooling fan 20...Motor (for electric work equipment) 21…Motor case 22... stator, 22a... first end, 22b... second end, 22c... inner periphery 22d…Stator core 23…Outer cylinder 24...teeth, 24a...inner circumferential end 25…Coil 26...insulator, 26a...inner periphery, 26b...connection portion, 26c...board connection portion 27...motor shaft, 27a, 27b...bearings 28...rotor, 28a...outer periphery, 28b...rotor core, 28c...magnet 29…Sprocket 30: sensor substrate, 30a: outer surface, 30b: inner surface 31: substrate body, 31a: outer periphery, 31b: inner periphery 32…legs 33…Mounting leg 34…Mold 35…Sensor 36…Diode 37…Signal line 38...Slit 39...Pattern, 39a...Inner pattern, 39b...Outer pattern 40...(Electric work machine) motor 41: sensor substrate, 41a: outer surface, 41b: inner surface 42...substrate body, 42a...outer periphery, 42b...inner periphery 43...legs 44…Mounting leg 46…Slope surface 47...Slit 48...pattern, 48a...inner pattern, 48b...outer pattern 50...(Electric work machine) motor 51...Sensor board 52...substrate body, 52a...periphery 53…Mold J: Motor axis

Claims

1. A motor for electric work equipment, A cylindrical stator, A rotor positioned on the inner circumference side of the stator, The stator has a sensor substrate provided at its axial end, The aforementioned sensor board is A substrate body located radially inward of the stator when viewed from the axial direction, It has legs that protrude radially outward from the main body of the substrate, The stator is exposed in at least one direction in the circumferential direction of the leg portion. A motor for an electric work machine having a sensor provided on the leg portion and facing the rotor, which detects the rotation of the rotor.

2. A motor for an electric work machine according to claim 1, The stator has a cylindrical outer cylinder and teeth that project radially inward from the outer cylinder and around which a coil is wound. A motor for an electric work machine in which the inner circumferential end of the teeth is exposed when viewed from the axial direction.

3. A motor for an electric work machine according to claim 1 or 2, The sensor substrate is a motor for an electric work machine having mounting legs that protrude radially outward from the substrate body and are attached to the stator.

4. A motor for an electric work machine according to claim 3, The stator has a cylindrical outer cylinder and a plurality of teeth that protrude radially inward from the outer cylinder and around which coils are wound. The aforementioned legs and mounting legs are provided in a motor for an electric work machine, positioned to avoid the centers of the radial inner ends of the plurality of teeth when viewed from the axial direction.

5. A motor for an electric work machine according to claim 4, The sensor substrate has at least one of the leg portions and at least one of the mounting legs, A motor for an electric work machine in which, when viewed from the axial direction, all of the legs and all of the mounting legs avoid the centers of the inner ends of the plurality of teeth, thereby exposing all of the centers of the inner ends of the plurality of teeth.

6. A motor for electric work equipment, The cylindrical outer casing of the stator, Multiple teeth on which a coil is wound, protruding radially inward from the outer cylindrical portion, A rotor arranged on the inner circumference side of the plurality of teeth, The stator has a sensor substrate provided at its axial end, The aforementioned sensor board is The substrate body is annular and, when viewed from the axial direction, is aligned radially inward with respect to the inner ends of the plurality of teeth, At least one inner end of the plurality of teeth is exposed radially outward of the substrate body. A motor for an electric work machine having a sensor provided on the sensor substrate and facing the rotor, which detects the rotation of the rotor.

7. A motor for an electric work machine according to claim 6, The sensor substrate is a motor for an electric work machine having mounting legs that protrude radially outward from the substrate body and are attached to the stator.

8. A motor for an electric work machine according to Claim 6, The sensor substrate has legs that protrude radially outward from the substrate body, and the sensor is mounted on the legs of the motor for an electric work machine.

9. A motor for an electric work machine according to claim 6, The sensor substrate has at least one mounting leg that protrudes radially outward from the substrate body and is attached to the stator, and at least one leg portion that protrudes radially outward from the substrate body and on which the sensor is provided. A motor for an electric work machine in which, when viewed from the axial direction, all of the legs and all of the mounting legs avoid the centers of the inner ends of the multiple teeth, thereby exposing all of the centers of the inner ends of the multiple teeth.

10. A motor for an electric work machine according to claim 1, 2, or 8, Having three of the aforementioned sensors, The sensor board is a motor for an electric work machine having three legs on which the sensor is provided.

11. A motor for electric work equipment, A cylindrical stator, A rotor positioned on the inner circumference side of the stator, The stator has a sensor substrate provided at its axial end, The aforementioned sensor board is A substrate body located radially inward from the inner peripheral edge of the stator when viewed from the axial direction, The outer surface of the substrate body located on the opposite side of the rotor, The outer surface of the substrate body has an inclined surface that slopes radially outward and axially inward towards the rotor where it is located. A gap is formed between the outer edge of the substrate body and the inner edge of the stator when viewed from the axial direction. A motor for an electric work machine having a sensor provided on the sensor substrate and facing the rotor, which detects the rotation of the rotor.

12. A motor for an electric work machine according to claim 11, Having a mold that covers the surface of the substrate body, The inclined surface is formed by the shape of the outer surface of the substrate body or the shape of the mold, for an electric work machine motor.

13. A motor for an electric work machine according to claim 11 or 12, The sensor substrate has mounting legs that protrude radially outward from the substrate body and are attached to the stator. The inclined surface is a motor for an electric work machine, provided to avoid the mounting legs.

14. A motor for an electric work machine according to claim 11 or 12, The sensor substrate has legs that protrude radially outward from the substrate body, and the sensor is mounted on the legs of the motor for an electric work machine.

15. A motor for an electric work machine according to claim 11 or 12, The inclined surface is inclined radially over the entire surface of the substrate body, from the inner edge to the outer edge, in the motor for an electric work machine.

Images