Electric work machine

Abstract

To waterproof a motor of an electric working machine.SOLUTION: An electric working machine includes: a motor having a stator including a coil, a rotor rotating with respect to the stator, and a rotor shaft fixed to the rotor; an output part driven by the rotor shaft; a moto case having an internal space where the stator and the rotor are arranged; a lead wire which is connected to the coil, and is arranged in a case opening of the motor case for connecting the internal space and an external space of the motor case; a resin part arranged so as to cover each of the coil and the lead wire in the internal space; and a cover member which has a cover opening where the lead wire is arranged, and is fixed to the motor case so as to block the case opening.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] A cable gland assembly such as that disclosed in Patent Document 1 is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 6,809,263 Summary of the Invention [Problem to be solved by the invention]

[0004] An electric work machine has a motor as a power source, and there are cases where it is desirable to protect the motor from water.

[0005] The technology disclosed in this specification aims to waterproof a motor of 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 and an output unit. The motor may have a stator including a coil, a rotor that rotates relative to the stator, and a rotor shaft fixed to the rotor. The output unit may be driven by the rotor shaft. The electric working machine may include a motor case having an internal space in which the stator and the rotor are disposed. The electric working machine may include lead wires connected to the coil. The lead wires may be disposed in a case opening of the motor case that connects the internal space with an external space of the motor case. The electric working machine may include a resin part that is disposed in the internal space so as to cover each of the coil and the lead wires. The electric working machine may include a cover member having a cover opening in which the lead wires are disposed. The cover member may be fixed to the motor case so as to close the case opening. [Effects of the Invention]

[0007] According to the technology disclosed in this specification, the motor of an electric work machine is waterproofed. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view from the left showing an electric operating machine according to this embodiment. [Figure 2] FIG. 2 is a perspective view from the left showing the motor assembly according to this embodiment. [Figure 3] FIG. 3 is a side view showing the motor assembly according to the present embodiment. [Figure 4] FIG. 4 is a vertical cross-sectional view showing the motor assembly according to this embodiment. [Figure 5] FIG. 5 is a cross-sectional view showing the motor assembly according to this embodiment. [Figure 6] FIG. 6 is an enlarged longitudinal cross-sectional view of a portion of the motor assembly according to this embodiment. [Figure 7] FIG. 7 is an exploded perspective view from the left showing the motor assembly according to this embodiment. [Figure 8]FIG. 8 is an exploded perspective view from the left showing the coil and the resin portion according to this embodiment. [Figure 9] FIG. 9 is an exploded perspective view from the left showing a part of the motor assembly according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] In one or more embodiments, the electric working machine may include a motor and an output unit. The motor may have a stator including a coil, a rotor that rotates relative to the stator, and a rotor shaft fixed to the rotor. The output unit may be driven by the rotor shaft. The electric working machine may include a motor case having an internal space in which the stator and the rotor are disposed. The electric working machine may include lead wires connected to the coil. The lead wires may be disposed in a case opening of the motor case that connects the internal space with an external space of the motor case. The electric working machine may include a resin portion disposed in the internal space so as to cover each of the coil and the lead wires. The electric working machine may include a cover member having a cover opening through which the lead wires are disposed. The cover member may be fixed to the motor case so as to close the case opening.

[0010] In the above configuration, the stator and rotor are disposed in the interior space of the motor case. The coil and lead wires are each covered with a resin portion in the interior space of the motor case. The case opening of the motor case, through which the lead wires are disposed, is closed with a cover member. This makes the motor waterproof. Also, the size of the motor case is prevented from increasing.

[0011] In one or more embodiments, the resin portion may have an opposing surface that contacts the cover member at the case opening.

[0012] In the above configuration, the cover member and the opposing surface of the resin portion come into contact with each other, making the motor waterproof.

[0013] In one or more embodiments, the electric operating machine may include a first seal member that seals the boundary between the resin portion, the cover member, and the lead wires in the cover opening.

[0014] In the above configuration, the boundaries between the resin portion, the cover member, and the lead wires are sealed by the first seal member, thereby preventing water from entering the internal space of the motor case.

[0015] In one or more embodiments, the first seal member may include an O-ring disposed between the resin portion and the cover member to surround the lead wire.

[0016] In the above configuration, the first seal member formed of an O-ring prevents water from entering the internal space of the motor case.

[0017] In one or more embodiments, the electric operating machine may include a second seal member that seals the boundary between the motor case and the peripheral edge of the cover member around the case opening.

[0018] In the above configuration, the boundary between the motor case and the cover member is sealed by the second seal member, thereby preventing water from entering the internal space of the motor case.

[0019] In one or more embodiments, the electric operating machine may include an external terminal connected to the coil, a connection terminal connected to the lead wire, and a screw for fastening the external terminal and the connection terminal. The resin portion may be disposed so as to cover each of the external terminal, the connection terminal, and the screw.

[0020] In the above configuration, a drive current is supplied to the coil via the connection terminal and the external terminal. The external terminal, the connection terminal, and the screw are each covered with a resin portion. This makes the external terminal and the connection terminal waterproof.

[0021] In one or more embodiments, the resin portion may contact the inner surface of the motor case.

[0022] In the above configuration, the heat of the coil is transferred to the motor case via the resin portion, and the heat of the coil transferred to the motor case is dissipated to the surroundings of the motor case.

[0023] In one or more embodiments, the motor case may include a main body having an insertion opening for inserting the stator, and a lid arranged to close the insertion opening and defining an internal space between the main body and the lid. The electric operating machine may include a third seal member that seals the boundary between the main body and the lid.

[0024] In the above configuration, the motor case can be separated into a main body and a lid, so that the stator can be inserted into the main body through the insertion opening in the main body. The boundary between the main body and the lid is sealed by the third seal member, so that water is prevented from entering the internal space of the motor case.

[0025] In one or more embodiments, at least a portion of the resin portion may be disposed so as to face the inner surface of the lid portion, and a third seal member may seal the boundary between the resin portion and the lid portion.

[0026] In the above configuration, the boundary between the resin portion and the lid portion is sealed by the third seal member, thereby preventing water from entering the internal space of the motor case.

[0027] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0028] 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 1.

[0029] The electric work machine 1 has a motor 12. In the embodiment, the direction parallel to the rotation axis AX of the motor 12 will be referred to as the axial direction, the radial direction of the rotation axis AX of the motor 12 will be referred to as the radial direction, and the direction circumferentially around the rotation axis AX of the motor 12 will be referred to as the circumferential direction or the rotation direction.

[0030] In the axial direction, a position close to or a direction approaching the center of the motor 12 will be referred to as the "axially inner" as appropriate, and a position far from or a direction away from the center of the motor 12 will be referred to as the "axially outer" as appropriate. In the radial direction, a position close to or a direction approaching the rotation axis AX of the motor 12 will be referred to as the "radially inner" as appropriate, and a position far from or a direction away from the rotation axis AX of the motor 12 will be referred to as the "radially outer" as appropriate. A position or a direction on one side in the circumferential direction will be referred to as the "one circumferential side" as appropriate, and a position or a direction on the other circumferential side will be referred to as the "other circumferential side" as appropriate.

[0031] [Electric work equipment] 1 is a left perspective view showing an electric work machine 1 according to this embodiment. In this embodiment, the electric work machine 1 is a chainsaw, which is a type of gardening tool (outdoor power equipment).

[0032] The electric work machine 1 includes a housing 2, a front grip portion 3, a hand guard 4, a battery cover 5, a controller 6, a trigger lock lever 7, a trigger switch 8, a guide bar 9, a saw chain 10, and a motor assembly 11.

[0033] The housing 2 is made of synthetic resin and has a motor accommodating portion 14, a battery holding portion 15, and a rear grip portion 16.

[0034] The motor housing 14 houses the motor assembly 11. The motor assembly 11 has a motor 12.

[0035] The battery holding portion 15 holds a battery pack (not shown). The battery holding portion 15 has a battery attachment portion to which the battery pack is attached. The battery holding portion 15 holds the battery pack via the battery attachment portion. The battery holding portion 15 is connected to the rear end portion of the motor accommodating portion 14. The battery cover 5 is arranged to cover the battery pack held in the battery holding portion 15.

[0036] The battery pack is detachably attached to the battery holding portion 15. The battery pack includes a secondary battery. In this embodiment, the battery pack includes a rechargeable lithium-ion battery. The battery pack functions as a power supply for the electric work machine 1. By being held in the battery holding portion 15, the battery pack can supply power to the electric work machine 1.

[0037] The rear grip portion 16 is held by the hand of a user of the electric work machine 1. The rear grip portion 16 is connected to the rear end portion of the battery holding portion 15. A portion of the rear grip portion 16 is connected to the upper part of the rear end portion of the battery holding portion 15. A portion of the rear grip portion 16 is connected to the lower part of the rear end portion of the battery holding portion 15.

[0038] An intake port 2A is provided on the left side of the motor housing portion 14. An exhaust port 2B is provided on the front side of the motor housing portion 14. Air outside the housing 2 can flow into the interior of the housing 2 through the intake port 2A. Air inside the housing 2 can flow out of the housing 2 through the exhaust port 2B.

[0039] The front grip portion 3 is held by the hand of a user of the electric work machine 1. The front grip portion 3 is made of synthetic resin. The front grip portion 3 is a pipe-shaped member. The front grip portion 3 is connected to the housing 2. The left end of the front grip portion 3 is connected to the left side surface of the motor accommodating portion 14. The right end of the front grip portion 3 is connected to the right side surface of the battery holding portion 15.

[0040] The hand guard 4 protects the hands of the user gripping the front grip 3. The hand guard 4 is disposed in front of the front grip 3. The hand guard 4 is connected to the upper part of the motor housing 14.

[0041] The controller 6 outputs a control signal for controlling the electric work machine 1. The controller 6 controls the drive current supplied from the battery pack to the motor 12. The controller 6 is housed in the motor housing portion .

[0042] The trigger lock lever 7 is operated by the user of the electric working machine 1 so as to set the trigger switch 8 in an operable state. The trigger lock lever 7 is disposed on the rear grip portion 16.

[0043] The trigger switch 8 is operated by a user of the electric work machine 1 to drive the motor 12 of the motor assembly 11. The trigger switch 8 is located on the rear grip portion 16. A user of the electric work machine 1 can grip the rear grip portion 16 with their hand, operate the trigger lock lever 7, and then operate the trigger switch 8 with their finger. When the trigger switch 8 is operated, a drive current is supplied to the motor 12, and the motor 12 is driven.

[0044] The guide bar 9 guides the saw chain 10. The guide bar 9 is a plate-shaped member that is long in the front-rear direction. The guide bar 9 extends forward from the housing 2.

[0045] The saw chain 10 is an output part of the electric work machine 1 driven by the motor 12. The saw chain 10 includes a plurality of cutters connected to each other. The saw chain 10 is arranged on the periphery of the guide bar 9. The motor 12 and the saw chain 10 are connected via a power transmission mechanism (not shown) including a sprocket. When the trigger switch 8 is operated and the motor 12 is driven, the saw chain 10 moves on the periphery of the guide bar 9.

[0046] [Motor Assembly] FIG. 2 is a perspective view from the left showing the motor assembly 11 according to this embodiment. FIG. 3 is a side view showing the motor assembly 11 according to this embodiment. FIG. 4 is a vertical cross-sectional view showing the motor assembly 11 according to this embodiment. FIG. 5 is a horizontal cross-sectional view showing the motor assembly 11 according to this embodiment. FIG. 6 is an enlarged vertical cross-sectional view of a portion of the motor assembly 11 according to this embodiment.

[0047] The motor assembly 11 includes a motor 12, a motor case 13, a bearing 18, a cooling fan 20, a sensor board 22, a sealing member 25, a resin part 19, a cover member 24, a sealing member 91, a sealing member 92, and a sealing member 26.

[0048] The motor 12 is a power source for the electric work machine 1. The motor 12 is an electric motor that is driven based on a driving current supplied from a battery pack.

[0049] The motor 12 is an inner rotor type brushless motor. The motor 12 has a stator 27, a rotor 28 that rotates relative to the stator 27, and a rotor shaft 29 that is fixed to the rotor 28. The stator 27 is disposed so as to surround at least a portion of the rotor 28. The rotor 28 rotates around a rotation axis AX. The saw chain 10 is driven by the rotor shaft 29.

[0050] In this embodiment, the rotation axis AX of the rotor 28 extends in the left-right direction. The axial direction parallel to the rotation axis AX coincides with the left-right direction.

[0051] The stator 27 includes a stator core 30 , an insulator 31 , a coil 32 , and a busbar unit 33 .

[0052] The stator core 30 includes a plurality of stacked steel plates. The steel plates are made of a metal whose main component is iron. The stator core 30 has an annular yoke 34 and teeth 35 that protrude radially inward from the inner surface of the yoke 34. The yoke 34 is arranged to surround the rotation axis AX. A plurality of teeth 35 are arranged in the circumferential direction. In this embodiment, twelve teeth 35 are arranged. The plurality of teeth 35 are arranged at equal intervals in the circumferential direction.

[0053] The insulator 31 covers at least a portion of the surface of the stator core 30. The insulator 31 covers at least the outer peripheral surfaces of the teeth 35. The insulator 31 is made of synthetic resin. The insulator 31 is fixed to the stator core 30. The insulator 31 is molded integrally with the stator core 30. The insulator 31 is fixed to the stator core 30 by insert molding.

[0054] The coils 32 are wound around the teeth 35 via insulators 31. The coils 32 and the stator core 30 are insulated by the insulators 31. A plurality of coils 32 are provided in the circumferential direction. In this embodiment, twelve coils 32 are provided.

[0055] The bus bar unit 33 is fixed to the insulator 31 by screws 53. A driving current from the battery pack is supplied to the bus bar unit 33 via the controller 6.

[0056] The busbar unit 33 includes an external terminal 42 , a short-circuiting member 44 , and an insulating member 45 .

[0057] The external terminal 42 is connected to each of the short-circuiting member 44 and the connection terminal 47. The external terminal 42 is connected to the coil 32 via the short-circuiting member 44. The short-circuiting member 44 connects (short-circuits) a pair of radially opposing coils 32. The external terminal 42 is connected to the battery pack via the connection terminal 47, a power line 46, and the controller 6. The external terminal 42 and the connection terminal 47 are fixed with screws 52. The connection terminal 47 is connected to the power line 46. The power line 46 is a lead wire connected to the coil 32 via the connection terminal 47, the external terminal 42, and the short-circuiting member 44. A driving current from the battery pack is supplied to the coil 32 via the controller 6, the power line 46, the connection terminal 47, the external terminal 42, and the short-circuiting member 44.

[0058] The insulating member 45 is made of synthetic resin. The insulating member 45 is provided so as to surround the rotation axis AX. The short-circuit member 44 is disposed inside the insulating member 45. The insulating member 45 supports the external terminal 42 and the short-circuit member 44.

[0059] The controller 6 controls the drive current supplied from the battery pack to the bus bar unit 33. The drive current from the battery pack is supplied to the external terminal 42 of the bus bar unit 33 via the controller 6, the power line 46, and the connection terminal 47. The drive current supplied from the battery pack to the external terminal 42 flows through the short-circuit member 44 and is then supplied to the coil 32.

[0060] The rotor 28 includes a rotor core 54 and a rotor magnet 55 .

[0061] The rotor core 54 includes a plurality of stacked steel plates. The steel plates are made of a metal whose main component is iron. The rotor core 54 is arranged to surround the rotation axis AX. The stator core 30 is arranged around the rotor core 54.

[0062] The rotor magnet 55 is a permanent magnet. The rotor magnet 55 is supported by the rotor core 54. The rotor magnet 55 is disposed inside the rotor core 54. A plurality of rotor magnets 55 are provided in the circumferential direction. In this embodiment, eight rotor magnets 55 are provided.

[0063] The rotor core 54 has a plurality of magnet holes 56 spaced apart in the circumferential direction. The magnet holes 56 are formed so as to penetrate the left and right end faces of the rotor core 54. The rotor magnets 55 are disposed in the magnet holes 56.

[0064] In this embodiment, the rotor core 54 has a plurality of hollow holes 57 spaced apart in the circumferential direction. The hollow holes 57 are formed so as to penetrate the left and right end faces of the rotor core 54. The hollow holes 57 are located radially inward of the magnet holes 56. In this embodiment, four hollow holes 57 are provided. The hollow holes 57 reduce the weight of the rotor core 54.

[0065] The rotor shaft 29 extends in the axial direction. The central axis of the rotor shaft 29 coincides with the rotation axis AX. The rotor shaft 29 is disposed inside the rotor core 54. The rotor core 54 and the rotor shaft 29 are fixed together. In this embodiment, a cylindrical member 58 is disposed around the rotor shaft 29. The cylindrical member 58 is formed from an electrically insulating material. The rotor shaft 29 is fixed to the rotor core 54 via the cylindrical member 58. A left portion of the rotor shaft 29 protrudes leftward from the left end face of the rotor core 54. A right portion of the rotor shaft 29 protrudes rightward from the right end face of the rotor core 54.

[0066] A driving current is supplied to the coil 32 from the battery pack via the controller 6, thereby generating a rotating magnetic field in the stator 27. The generation of the rotating magnetic field causes the rotor 28 and rotor shaft 29 to rotate about the rotation axis AX.

[0067] The motor case 13 accommodates at least a portion of the motor 12. In this embodiment, the motor case 13 accommodates at least a stator 27 and a rotor 28. The motor case 13 has an internal space in which the stator 27 and the rotor 28 are disposed. In the internal space of the motor case 13, the stator 27 is disposed so as to surround at least a portion of the rotor 28. The internal space is a closed space. In this embodiment, the internal space is a substantially sealed space. A portion of the rotor shaft 29 is disposed in the internal space.

[0068] The motor case 13 is made of metal. In this embodiment, the motor case 13 is made of aluminum. The motor case 13 may also be made of aluminum die-cast (ADC12).

[0069] The motor case 13 includes a main body 60 , heat dissipation fins 61 , and a lid 62 .

[0070] The main body 60 accommodates the stator 27 and the rotor 28. The stator 27 and the rotor 28 are disposed inside the main body 60.

[0071] The main body 60 includes a cylindrical portion 60A, a lead wire holding portion 60B, and a wall portion 60C. The cylindrical portion 60A is arranged to surround the rotation axis AX. The lead wire holding portion 60B is arranged at the front of the cylindrical portion 60A. The lead wire holding portion 60B protrudes forward from the front of the cylindrical portion 60A. The wall portion 60C is connected to the right end of the cylindrical portion 60A. An insertion opening 63 is provided at the left end of the main body 60 and the lead wire holding portion 60B. The stator 27 is inserted into the inside of the main body 60 through the insertion opening 63.

[0072] The heat dissipation fins 61 are provided on the outer surface of the cylindrical portion 60A. The heat dissipation fins 61 are provided so as to protrude radially outward from the outer surface of the cylindrical portion 60A. The heat dissipation fins 61 are arranged so as to extend in the axial direction on the outer surface of the cylindrical portion 60A. A plurality of the heat dissipation fins 61 are provided at intervals in the circumferential direction.

[0073] The lid portion 62 is fixed to the main body portion 60 so as to close the insertion opening 63 of the main body portion 60. By connecting the main body portion 60 and the lid portion 62 so that the insertion opening 63 is closed by the lid portion 62, an internal space is formed between the main body portion 60 and the lid portion 62. After at least a portion of the motor 12 including the stator 27 is disposed inside the main body portion 60, the insertion opening 63 of the main body portion 60 is closed by the lid portion 62, so that at least a portion of the motor 12 is disposed in the internal space.

[0074] A plurality of screw bosses 69 are provided around the insertion opening 63 in the main body 60. In this embodiment, four screw bosses 69 are provided at intervals in the circumferential direction. A threaded hole is provided in each of the plurality of screw bosses 69. A plurality of screw bosses 70 are provided around the periphery of the lid 62. In this embodiment, four screw bosses 70 are provided at intervals in the circumferential direction. An opening is provided in each of the plurality of screw bosses 70. With the middle portion of a screw 71 positioned in the opening of the screw boss 70, the tip of the screw 71 is engaged with the threaded hole of the screw boss 69, thereby fixing the main body 60 and the lid 62 together.

[0075] The lid portion 62 includes a disk portion 62A and a lead wire holding portion 62B. The disk portion 62A is connected to the cylindrical portion 60A. The lead wire holding portion 62B is connected to the lead wire holding portion 60B. The lead wire holding portion 62B is provided in front of the disk portion 62A.

[0076] The bearing 18 supports the rotor shaft 29. The rotor shaft 29 is rotatably supported by the bearing 18. The bearing 18 is supported by the motor case 13.

[0077] The motor case 13 has a shaft hole 72 in which at least a portion of the rotor shaft 29 is disposed. The shaft hole 72 is provided to connect the internal space of the motor case 13 with the external space of the motor case 13. The shaft hole 72 includes a shaft hole 72L in which the left portion of the rotor shaft 29 is disposed, and a shaft hole 72R in which the right portion of the rotor shaft 29 is disposed. The shaft hole 72L is provided in the disk portion 62A of the lid portion 62. The shaft hole 72R is provided in the wall portion 60C of the main body portion 60.

[0078] The motor case 13 has a peripheral wall portion 101 that defines the shaft hole 72. The peripheral wall portion 101 is substantially cylindrical. The peripheral wall portion 101 includes a peripheral wall portion 101L that defines the shaft hole 72L and a peripheral wall portion 101R that defines the shaft hole 72R. The peripheral wall portion 101L is provided on the circular plate portion 62A of the lid portion 62. The peripheral wall portion 101L protrudes leftward from the left surface of the circular plate portion 62A. The peripheral wall portion 101R is provided on the wall portion 60C of the main body portion 60. The peripheral wall portion 101R protrudes rightward from the right surface of the wall portion 60C.

[0079] The bearings 18 include a left bearing 18L that supports a left portion of the rotor shaft 29 and a right bearing 18R that supports a right portion of the rotor shaft 29. The left bearing 18L is disposed in the shaft hole 72L. The right bearing 18R is disposed in the shaft hole 72R.

[0080] The left and right ends of the rotor shaft 29 are disposed outside the motor case 13. The right end of the rotor shaft 29 is connected to the saw chain 10 via a power transmission mechanism (not shown) including a sprocket. The saw chain 10 is driven by the rotor shaft 29. The saw chain 10 is driven by the rotation of the rotor shaft 29.

[0081] The cooling fan 20 is disposed outside the motor case 13. The cooling fan 20 faces at least a portion of the outer surface of the motor case 13. The cooling fan 20 is fixed to a rotor shaft 29. The cooling fan 20 is rotated by the rotor shaft 29.

[0082] In this embodiment, the cooling fan 20 is disposed to the left of the motor case 13. The cooling fan 20 is fixed to the left end of the rotor shaft 29 disposed outside the motor case 13. The cooling fan 20 faces at least a portion of the outer surface of the motor case 13. In this embodiment, the cooling fan 20 is disposed so as to face at least a portion of the lid portion 62.

[0083] In this embodiment, the cooling fan 20 is a centrifugal fan. The cooling fan 20 has an inlet 20A provided at the left end of the cooling fan 20 and an outlet 20F provided at the periphery of the cooling fan 20. The cooling fan 20 generates an air flow that cools the motor case 13. When the rotor shaft 29 rotates, the cooling fan 20 rotates together with the rotor shaft 29. When the cooling fan 20 rotates, air around the cooling fan 20 is drawn into the inlet 20A. The air drawn into the inlet 20A is blown out through the outlet 20F. At least a portion of the air blown out through the outlet 20F hits the outer surface of the motor case 13. This cools the motor case 13.

[0084] In this embodiment, the cooling fan 20 is fixed to the rotor shaft 29 via a fan bushing 73. The fan bushing 73 is an intermediate member that connects the rotor shaft 29 and the cooling fan 20. The fan bushing 73 is disposed outside the motor case 13 so as to connect the left end of the rotor shaft 29 and the cooling fan 20. When the cooling fan 20 rotates, the fan bushing 73 rotates together with the cooling fan 20.

[0085] The sensor board 22 supports the magnetic sensor 74. The sensor board 22 is disposed inside the motor case 13. The sensor board 22 is annular. The sensor board 22 is disposed around the rotor shaft 29. The sensor board 22 includes a printed wiring board (PWB). An example of a material for forming the sensor board 22 is epoxy resin. The sensor board 22 may be made of a metal such as aluminum, or may be made of a heat-dissipating resin having a higher thermal conductivity than epoxy resin.

[0086] In the axial direction, the sensor board 22 is disposed between at least a portion of the motor case 13 and the stator 27. The sensor board 22 is fixed to the motor case 13. The sensor board 22 is fixed to the cover portion 62 with screws 78.

[0087] The magnetic sensor 74 detects the rotor magnet 55. The magnetic sensor 74 is supported on the sensor board 22 so as to face the rotor magnet 55. An example of the magnetic sensor 74 is a Hall element. The magnetic sensor 74 detects the rotation of the rotor 28 by detecting the rotor magnet 55. Signal lines 75 are connected to the sensor board 22. Five signal lines 75 are arranged. A detection signal from the magnetic sensor 74 is transmitted to the controller 6 via the signal lines 75.

[0088] In this embodiment, at least a portion of the surface of the magnetic sensor 74 and the sensor substrate 22 is covered with a resin film 76. The resin film 76 functions as a heat insulating film.

[0089] The seal member 25 seals the boundary between the rotor shaft 29 and the motor case 13. The seal member 25 includes an oil seal. The seal member 25 is disposed in the shaft hole 72. The seal member 25 is press-fitted between the rotor shaft 29 and the peripheral wall portion 101. The seal member 25 is supported by the peripheral wall portion 101. The seal member 25 includes a seal member 25L that seals the boundary between the left portion of the rotor shaft 29 and the motor case 13, and a seal member 25R that seals the boundary between the right portion of the rotor shaft 29 and the motor case 13. The seal member 25L is disposed in the shaft hole 72L. The seal member 25R is disposed in the shaft hole 72R.

[0090] A stopper member 108L is disposed on the left side of the seal member 25L. A stopper member 108R is disposed on the right side of the seal member 25R. The stopper member 108L prevents the seal member 25L from slipping out of the shaft hole 72L. The stopper member 108R prevents the seal member 25R from slipping out of the shaft hole 72R. Examples of the stopper members 108L and 108R are circlips.

[0091] [Resin part] Fig. 7 is an exploded perspective view from the left showing the motor assembly 11 according to this embodiment. Fig. 8 is an exploded perspective view from the left showing the coil 32 and the resin part 19 according to this embodiment. Fig. 9 is an exploded perspective view from the left showing a part of the motor assembly 11 according to this embodiment.

[0092] The resin portion 19 is made of synthetic resin. The resin portion 19 is disposed in the internal space of the motor case 13. The resin portion 19 fills the internal space of the motor case 13. The resin portion 19 is disposed in the internal space of the motor case 13 so as to cover the coil 32 and the power supply line 46. The resin portion 19 is disposed in the internal space of the motor case 13 so as to cover the stator core 30 and the insulator 31. The resin portion 19 is disposed in the internal space of the motor case 13 so as to cover the bus bar unit 33. The resin portion 19 is disposed in the internal space of the motor case 13 so as to cover the external terminals 42, the connection terminals 47, and the screws 52.

[0093] The resin part 19 is arranged so as to contact the inner surface of the motor case 13. The resin part 19 is arranged so as to contact the inner surface of the main body part 60 and the inner surface of the lid part 62, respectively.

[0094] The resin portion 19 has high thermal conductivity and electrical insulation. For example, if the insulator 31 is made of nylon resin, which has a thermal conductivity of 0.2 W / m K, the thermal conductivity of the synthetic resin used for the resin portion 19 is higher than 0.2 W / m K.

[0095] An example of an insulating synthetic resin having a thermal conductivity higher than 0.2 W / m K is unsaturated polyester resin. The resin portion 19 may be made of nylon resin containing an insulating, thermally conductive filler.

[0096] After the stator 27, busbar unit 33, connection terminals 47, and screws 52 are inserted into the inside of the main body 60 through the insertion openings 63, heated and melted synthetic resin is supplied into the inside of the main body 60 through the insertion openings 63. The synthetic resin supplied into the inside of the main body 60 is solidified, thereby forming the resin part 19 so as to fill the internal space of the motor case 13.

[0097] The motor case 13 has a case opening 80 that connects the internal space of the motor case 13 to the external space of the motor case 13. The case opening 80 is provided between the lead wire holding portion 60B of the main body 60 and the lead wire holding portion 62B of the lid 62.

[0098] The cover member 24 is disposed so as to cover the case opening 80. The cover member 24 is a plate-shaped member. The cover member 24 may be made of metal or synthetic resin. The cover member 24 is fixed to the motor case 13 so as to close the case opening 80. In this embodiment, the cover member 24 is fixed to the main body 60 with two screws 99. The cover member 24 has screw openings 82. The screw openings 82 are provided at the upper and lower ends of the cover member 24. The lead wire holding portion 60B of the main body 60 has screw holes 83. The screw holes 83 are provided above and below the case opening 80. The screws 99 are inserted into the screw holes 83 through the screw openings 82, thereby fixing the cover member 24 to the lead wire holding portion 60B of the main body 60 with the screws 99.

[0099] The power line 46 and a portion of the resin part 19 are arranged in the case opening 80. The power line 46 is held by the resin part 19. In the case opening 80, the resin part 19 is arranged around the power line 46. In the case opening 80, the resin part 19 is arranged between the outer surface of the power line 46 and the inner surface of the motor case 13 that defines the case opening 80. The resin part 19 has an opposing surface 19A that faces the rear surface of the cover member 24 in the case opening 80. The rear surface of the cover member 24 and the opposing surface 19A of the resin part 19 come into contact with each other.

[0100] The cover member 24 has a cover opening 81 through which the power line 46 is disposed. Three cover openings 81 are provided. The three cover openings 81 are disposed at intervals in the up-down direction. In the up-down direction, the three cover openings 81 are disposed between pairs of screw openings 82.

[0101] The sealing member 91 seals the boundary between the resin part 19, the cover member 24, and the power line 46 in the cover opening 81. The sealing member 91 includes an O-ring that is disposed between the resin part 19 and the cover member 24 so as to surround the power line 46. The sealing member 91 contacts the opposing surface 19A of the resin part 19, the rear surface of the cover member 24, and the outer surface of the power line 46.

[0102] The seal member 92 seals the boundary between the motor case 13 around the case opening 80 and the peripheral edge of the rear surface of the cover member 24. The seal member 92 includes an O-ring arranged to surround the case opening 80. The seal member 92 contacts the peripheral edge of the rear surface of the cover member 24. A portion of the seal member 92 contacts the outer surface of the main body portion 60 around the case opening 80. A portion of the seal member 92 contacts the outer surface of the lid portion 62 around the case opening 80.

[0103] The sealing member 26 seals the boundary between the main body 60 and the lid 62. At least a portion of the cylindrical portion 60A of the main body 60 is arranged to face the inner surface (right surface) of the lid 62. At least a portion of the resin portion 19 is arranged to face the inner surface (right surface) of the lid 62. The sealing member 26 seals the boundary between the main body 60 and the lid 62, as well as the boundary between the resin portion 19 and the lid 62.

[0104] The sealing member 26 includes an O-ring. The sealing member 26 is arranged to surround the insertion opening 63. The recess 109 is formed at the left end of the main body 60 facing the inner surface of the lid 62 and at the left end of the resin part 19. The recess 109 is formed to extend between the main body 60 and the resin part 19. The recess 109 is formed to surround the insertion opening 63. The sealing member 26 is arranged in the recess 109.

[0105] <Effects> As described above, in this embodiment, the electric work machine 1 includes the motor 12 and the saw chain 10, which is an output unit. The motor 12 includes the stator 27, which includes the coil 32, the rotor 28, which rotates relative to the stator 27, and the rotor shaft 29, which is fixed to the rotor 28. The saw chain 10 is driven by the rotor shaft 29. The electric work machine 1 includes the motor case 13, which has an internal space in which the stator 27 and the rotor 28 are disposed. The electric work machine 1 includes the power supply line 46, which is a lead wire connected to the coil 32. The power supply line 46 is disposed in a case opening 80 of the motor case 13, which connects the internal space of the motor case 13 with the external space of the motor case 13. The electric work machine 1 includes the resin part 19, which is disposed in the internal space of the motor case 13 so as to cover the coil 32 and the power supply line 46. The electric work machine 1 includes the cover member 24, which has a cover opening 81 through which the power supply line 46 is disposed. The cover member 24 is fixed to the motor case 13 so as to close the case opening 80 .

[0106] In the above configuration, the stator 27 and the rotor 28 are disposed in the internal space of the motor case 13. The coil 32 and the power line 46 are each covered by the resin part 19 in the internal space of the motor case 13. The case opening 80 of the motor case 13, through which the power line 46 is disposed, is closed by the cover member 24. This makes the motor 12 waterproof. Furthermore, an increase in the size of the motor case 13 is suppressed.

[0107] In this embodiment, the resin part 19 has an opposing surface 19A that contacts the cover member 24 at the case opening 80.

[0108] In the above configuration, the cover member 24 and the opposing surface 19A of the resin part 19 come into contact with each other, so that the motor 12 is waterproofed.

[0109] In this embodiment, the electric operating machine 1 includes a seal member 91, which is a first seal member that seals the boundary between the resin part 19, the cover member 24, and the power line 46 in the cover opening 81.

[0110] In the above configuration, the boundaries between the resin part 19, the cover member 24, and the power line 46 are sealed by the sealing member 91, so that water is prevented from entering the internal space of the motor case 13.

[0111] In this embodiment, the sealing member 91 includes an O-ring that is disposed between the resin portion 19 and the cover member 24 so as to surround the power line 46 .

[0112] In the above configuration, the seal member 91 formed of an O-ring prevents water from entering the internal space of the motor case 13.

[0113] In this embodiment, the electric operating machine 1 includes a seal member 92, which is a second seal member that seals the boundary between the motor case 13 around the case opening 80 and the peripheral edge of the cover member .

[0114] In the above configuration, the boundary between the motor case 13 and the cover member 24 is sealed by the seal member 92, so that water is prevented from entering the internal space of the motor case 13.

[0115] In this embodiment, the electric operating machine 1 includes an external terminal 42 connected to the coil 32, a connection terminal 47 connected to a power line 46, and a screw 52 that fastens the external terminal 42 to the connection terminal 47. The resin part 19 is disposed so as to cover each of the external terminal 42, the connection terminal 47, and the screw 52.

[0116] In the above configuration, a drive current is supplied to the coil 32 via the connection terminal 47 and the external terminal 42. Furthermore, the external terminal 42, the connection terminal 47, and the screw 52 are each covered with the resin part 19. This makes the external terminal 42 and the connection terminal 47 waterproof.

[0117] In this embodiment, the resin portion 19 comes into contact with the inner surface of the motor case 13 .

[0118] In the above configuration, the heat of the coil 32 is transferred to the motor case 13 via the resin portion 19. The heat of the coil 32 transferred to the motor case 13 is dissipated to the periphery of the motor case 13.

[0119] In this embodiment, the motor case 13 includes a main body 60 having an insertion opening 63 through which the stator 27 is inserted, and a lid 62 that is arranged to close the insertion opening 63 and forms an internal space of the motor case 13 between the main body 60 and the lid 62. The electric operating machine 1 is provided with a third sealing member 26 that seals the boundary between the main body 60 and the lid 62.

[0120] In the above configuration, motor case 13 can be separated into main body 60 and lid 62, so that stator 27 can be inserted into main body 60 through insertion opening 63 of main body 60. The boundary between main body 60 and lid 62 is sealed by sealing member 26, so that water is prevented from entering the internal space of motor case 13.

[0121] In this embodiment, at least a portion of the resin portion 19 is disposed so as to face the inner surface of the lid portion 62. The seal member 26 seals the boundary between the resin portion 19 and the lid portion 62.

[0122] In the above configuration, the boundary between the resin part 19 and the lid part 62 is sealed by the sealing member 26, so that water is prevented from entering the internal space of the motor case 13.

[0123] [Other embodiments] In the above-described embodiment, the external terminals 42 and the connection terminals 47 may be omitted.

[0124] In the above-described embodiment, the motor 12 is an inner rotor brushless motor. However, the motor 12 may be an outer rotor brushless motor. In an outer rotor brushless motor, the teeth protrude radially outward from the annular yoke.

[0125] In the above-described embodiment, the electric work machine 1 is a chainsaw, which is a type of gardening tool. The gardening tool is not limited to a chainsaw. Examples of gardening tools include a hedge trimmer, a lawn mower, a brush cutter, and a blower. The electric work machine 1 may also be a power tool. Examples of power tools include a driver drill, a percussion driver drill, an angle drill, an impact driver, a grinder, a hammer, a hammer drill, a circular saw, and a reciprocating saw.

[0126] In the above-described embodiment, the battery pack attached to the battery attachment portion is used as the power source for the electric working machine. However, a commercial power source (AC power source) may also be used as the power source for the electric working machine. [Explanation of symbols]

[0127] 1...electric work machine, 2...housing, 2A...intake port, 2B...exhaust port, 3...front grip section, 4...hand guard, 5...battery cover, 6...controller, 7...trigger lock lever, 8...trigger switch, 9...guide bar, 10...saw chain (output section), 11...motor assembly, 12...motor, 13...motor case, 14...motor housing section, 15...battery holding section, 16...rear grip section, 18...bearing, 18L...left bearing, 18R...right bearing, 19...resin part, 19A...opposing surface, 20...cooling fan, 20A...intake port, 20F...blowout port, 22...sensor board, 24...cover member, 25...sealing member, 25L...sealing member, 25R...sealing member, 26...sealing member (third sealing member), 27...stator, 28...rotor, 29...rotor shaft, 30...stator core, 31...insulator, 32...coil, 33...busbar unit, 34...yoke, 35...teeth , 42...external terminal, 44...short-circuit member, 45...insulating member, 46...power line, 47...connection terminal, 52...screw, 53...screw, 54...rotor core, 55...rotor magnet, 56...magnet hole, 57...hollow hole, 58...cylindrical member, 60...main body portion, 60A...cylindrical portion, 60B...lead wire holding portion, 60C...wall portion, 61...heat dissipation fin, 62...lid portion, 62A...disk portion, 62B...lead wire holding portion, 63...insertion port, 69...screw boss portion, 70...screw boss portion, 71...screw, 72...shield Shaft hole, 72L...shaft hole, 72R...shaft hole, 73...fan bushing, 74...magnetic sensor, 75...signal line, 76...resin film, 78...screw, 80...case opening, 81...cover opening, 82...screw opening, 83...screw hole, 91...sealing member (first sealing member), 92...sealing member (second sealing member), 99...screw, 101...circumferential wall portion, 101L...circumferential wall portion, 101R...circumferential wall portion, 108L...stopper member, 108R...stopper member, 109...recess.

Claims

1. a motor having a stator including a coil, a rotor that rotates relative to the stator, and a rotor shaft that is fixed to the rotor; an output section driven by the rotor shaft; a motor case having an internal space in which the stator and the rotor are disposed; a lead wire connected to the coil and disposed in a case opening of the motor case, the lead wire connecting the internal space and an external space of the motor case; a resin portion disposed in the internal space so as to cover the coil and the lead wire; a cover member having a cover opening in which the lead wires and a part of the resin portion are disposed, the cover member being fixed to the motor case so as to close the case opening and to be in contact with the resin portion. Electric work equipment.

2. the resin portion has an opposing surface that contacts the cover member at the case opening; The electric operating machine according to claim 1 .

3. a first seal member that seals the boundary between the resin portion, the cover member, and the lead wires in the cover opening; The electric operating machine according to claim 2.

4. the first seal member includes an O-ring disposed between the resin portion and the cover member so as to surround the lead wire; The electric operating machine according to claim 3.

5. a second seal member that seals the boundary between the motor case and the peripheral edge of the cover member around the case opening; The electric operating machine according to any one of claims 1 to 4.

6. an external terminal connected to the coil; a connection terminal connected to the lead wire; a screw for fixing the external terminal and the connection terminal together; the resin portion is disposed so as to cover the external terminals, the connection terminals, and the screws, respectively. The electric operating machine according to any one of claims 1 to 5.

7. the resin portion contacts the inner surface of the motor case; The electric operating machine according to any one of claims 1 to 6.

8. the motor case includes a main body portion having an insertion opening into which the stator is inserted, and a lid portion disposed to close the insertion opening and defining the internal space between the main body portion and the lid portion; a third seal member that seals the boundary between the main body and the lid; The electric operating machine according to any one of claims 1 to 7.

9. At least a portion of the resin portion is disposed to face the inner surface of the lid portion, The third seal member seals the boundary between the resin portion and the lid portion. The electric operating machine according to claim 8.

10. a motor having a stator including a coil, a rotor that rotates relative to the stator, and a rotor shaft that is fixed to the rotor; an output section driven by the rotor shaft; a motor case having an internal space in which the stator and the rotor are disposed; a lead wire connected to the coil and disposed in a case opening of the motor case, the lead wire connecting the internal space and an external space of the motor case; a resin portion disposed in the internal space so as to cover the coil and the lead wire; a cover member having a cover opening through which the lead wires are arranged and fixed to the motor case so as to close the case opening, the resin portion has an opposing surface that contacts the cover member at the case opening; Electric work equipment.

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