Electric working machine

Abstract

The present invention provides an electric working machine that can suppress the risk of contact between a control unit and wiring arranged inside a motor housing. The electric working machine (1A) accommodates a motor (6) and a control unit (13) inside a motor housing (2). A gear box (4) is connected to the front of the motor housing (2), and a handle housing (3) is connected to the rear of the motor housing (2). The motor housing (2) is an integrally molded cylindrical shape. The electrical connection between the wiring of the motor (6) and the wiring of the control unit (13) is performed through a connector (23) outside the motor housing (2) and inside the handle housing (3) at the rear. The control unit (13) has a switching element for energizing the motor (6).

Description

Technical Field

[0001] The present invention relates to an electric working machine having a motor and a control unit inside a motor housing. Background Art

[0002] As power tools become increasingly high in output, there is known a structure in which a heating element or a heat dissipation member connected to the heating element is exposed to the outside through which cooling air passes (hereinafter also referred to as an "element exposure structure") in order to cool the heating element.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-203329 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the case of the component exposure structure, there is a concern that an electrical component or a member that may be energized may come into contact with a portion of wiring such as a power line where the insulation cover is removed, thereby causing a problem. In particular, when the component exposure structure is used in a structure where a control unit such as a controller is to be housed inside a motor housing that houses a motor, there is a possibility that the wiring (particularly the portion where the insulation cover is removed) may come into contact with a energized portion or a heat generating portion of the control unit.

[0008] The present invention was made in recognition of such a situation, and an object of the present invention is to provide an electric working machine capable of suppressing contact between a control unit provided inside a motor case and wiring.

[0009] Technical means of solving problems

[0010] One embodiment of the present invention is an electric working machine. The electric working machine is characterized in that it includes a motor housing, the motor housing accommodating a motor and a first control unit for controlling the motor, and an electrical connection portion between the motor and the first control unit is located outside the motor housing.

[0011] The first control unit may include a switching element for energizing the motor.

[0012] A fixture may be provided on the electrical connection portion side of the motor housing, a plurality of fixture through holes may be provided on the fixture, and the motor side wiring may be inserted through the fixture through holes. In addition, the control portion side wiring may be inserted through the fixture through holes located at positions different from the fixture through holes through which the motor side wiring passes.

[0013] A gear box may be connected to one side of the motor housing, and the electrical connection portion is located at the other side of the motor housing. In addition, a handle housing may be provided at the other side of the motor housing, and the electrical connection portion is located inside the handle housing.

[0014] There may be a fan rotated by the motor, and an air intake port and an air exhaust port for generating a flow of air for cooling the motor by the rotation of the fan, and the air flowing in from the air intake port passes through the fixture through-hole and then flows into the motor housing.

[0015] The electrical connection portion between the motor and the first control unit may include a connector, and a fixture for holding the connector may be provided on the other side of the motor housing.

[0016] The motor housing may be a cylindrical integral structure formed in an indivisible manner.

[0017] The motor may be a brushless motor, and the first control unit may be an inverter circuit that controls power supply to the motor.

[0018] In addition, any combination of the above-mentioned components, or expressions of the present invention converted between methods, systems, and the like are also effective as embodiments of the present invention.

[0019] Effects of the Invention

[0020] According to the present invention, it is possible to provide an electric working machine capable of suppressing contact between a control unit provided inside a motor case and wiring. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a side sectional view of the electric working machine 1A according to the first embodiment of the present invention.

[0022] Figure 2 It is an assembly explanation diagram of the motor case 2, the motor 6, the control unit 13, and the fixture 17 of the electric working machine 1A.

[0023] Figure 3 1A is a rear view of the motor case 2 in which the motor 6 is incorporated.

[0024] Figure 4 is from Figure 3 This is a back view of the motor housing 2 in which the control unit 13 is incorporated.

[0025] Figure 5 is Figure 4 A rear view of the motor housing 2 with the fixture 17 installed therein.

[0026] Figure 6 The connector 23 has been used to Figure 5 The back view shows the state where the wiring 6w and the wiring 47w are connected to each other.

[0027] Figure 7 It is a side sectional view of an electric working machine 1B according to Embodiment 2 of the present invention.

[0028] Figure 8 1B is a rear view of a motor case 2 in which a motor 6 is incorporated.

[0029] Fig. 9 is from Figure 8 FIG. 2 is a back view of the motor case 2 in which the bridge inverter board 30 is incorporated.

[0030] Fig.10 is Fig. 9 A rear view of the motor housing 2 with the fixture 17 installed therein.

[0031] Fig.11 Yes Fig.10 The rear view is a state where the connectors 6n and 47n are connected to each other and embedded in the recess 17b of the holder 17.

[0032] Fig.12 This is a circuit diagram of the electric working machine 1B.

[0033] [Explanation of Reference Numerals]

[0034] 1A, 1B: Electric working machine

[0035] 2: Motor housing

[0036] 3: Handle housing (tail cover)

[0037] 4: Gearbox

[0038] 5: Speed ​​reduction mechanism (rotation transmission mechanism)

[0039] 6: Motor

[0040] 6n: Connector

[0041] 6w: Wiring

[0042] 7: Trigger

[0043] 8: Spindle

[0044] 8a: Grindstone

[0045] 9: Power cord

[0046] 11: First switch (contact switch)

[0047] 12: Second switch (electronic switch)

[0048] 13: Control Department

[0049] 14: Battery Pack

[0050] 15, 16: Diode bridge

[0051] 17: Fixer (intermediate member)

[0052] 17a: Rib

[0053] 17b: concave part

[0054] 20: Controller

[0055] 21: Calculation unit (second control unit)

[0056] 22: IPD circuit

[0057] 23: Connector (wiring component)

[0058] 26: Regulator

[0059] 27: Radiator (heat dissipation component)

[0060] 28: Bearing

[0061] 30: Bridge inverter substrate (drive substrate)

[0062] 40: Sensor substrate

[0063] 42: Hall element (magnetic sensor)

[0064] 47: Inverter circuit (first control unit)

[0065] 47n: Connector

[0066] 47w: Wiring

[0067] 50: AC power supply DETAILED DESCRIPTION

[0068] Hereinafter, a suitable embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same symbols are added to the same or equivalent components, members, etc. shown in each of the drawings, and repeated descriptions are appropriately omitted. In addition, the embodiments do not limit the invention but are exemplified, and all the features or combinations thereof described in the embodiments are not necessarily the essence of the invention.

[0069] (Implementation Method 1) Figure 1 to Figure 6 An electric working machine 1A according to a first embodiment of the present invention will be described. Figure 1The vertical direction and the front-rear direction of the electric working machine 1A are defined. The front-rear direction is parallel to the extending direction of the rotating shaft 6a of the motor 6. The electric working machine 1A is a cordless grinder that operates by power supplied from a detachably mounted battery pack 14.

[0070] The electric working machine 1A is formed into a housing by a motor housing 2, a handle housing (tail cover) 3, and a gear box 4. The handle housing 3 is mounted (connected) to the rear end of the motor housing 2 via a fixture (intermediate member) 17, and the gear box 4 is mounted (connected) to the front end of the motor housing 2. The motor housing 2 and the handle housing 3 are, for example, resin molded bodies. The gear box 4 is, for example, made of metal such as aluminum. The gear box 4 supports a bearing 6b that rotatably supports the front portion of the rotating shaft 6a.

[0071] The battery pack 14, which serves as the power supply source of the electric working machine 1A, is detachably mounted on the rear end of the handle housing 3. The handle housing 3 constitutes the handle of the electric working machine 1A. The trigger 7 is swingably (rotatably) supported at the lower part of the handle housing 3. The trigger 7 is an operating part for the user to switch the on / off of the first switch 11 provided in the current path of the motor 6. The first switch 11 is preferably a mechanical contact switch, which is accommodated in the handle housing 3 and is located above the trigger 7. If the user holds the trigger 7, the trigger 7 is swung upward and the first switch 11 is turned on. If the user releases the grip of the trigger 7, the trigger 7 is swung downward and the first switch 11 is turned off.

[0072] The motor housing 2 is a cylindrical integral structure such as a cylindrical shape extending in the front-to-back direction and formed in an indivisible manner, and the front and rear ends are open. The motor housing 2 accommodates the motor 6, and accommodates the control unit 13 at the rear of the motor 6. The control unit 13 includes an inverter circuit that controls the power supply to the motor 6, or a microcomputer (microcontroller) that controls the inverter circuit. The motor 6 is an inner rotor type brushless motor. In addition, a fan 10 for cooling the motor 6 and the control unit 13 is provided at the front of the motor housing 2. The fan 10 rotates integrally with the rotating shaft 6a, and generates cooling wind from the air intake 3a provided on the left and right of the handle housing 3 to the exhaust port 4a provided in the gear box 4 by rotating. That is, the air flowing into the handle housing 3 from the air intake 3a by the rotation of the fan 10 flows into the motor housing 2 as cooling wind, cools the control unit 13, cools the motor 6, and is then discharged to the outside from the exhaust port 4a. The gear box 4 accommodates the speed reduction mechanism 5 as a rotation transmission mechanism. The speed reduction mechanism 5 is a mechanism composed of a pair of bevel gears, which reduces the speed of the motor 6 and transmits it to the spindle 8 after changing the speed by 90 degrees. The grindstone 8a as a rotating tool (tip tool) is rotatably provided at the lower end of the spindle 8. The mechanical structure and operation from the rotation of the motor 6 to the rotation of the grindstone 8a are well known, so a more detailed description is omitted.

[0073] like Figure 2 As shown, the motor 6 is inserted into the motor case 2 from the front for assembly. The control unit 13 is inserted into the motor case 2 from the rear for assembly. The fixture 17 is fixed to the rear end of the motor case 2 by screwing or the like. Figure 3This is a view of the motor housing 2 in which the motor 6 is installed, viewed from the rear. The motor housing 2 has a bearing retaining portion 2a. The bearing retaining portion 2a is located between the motor 6 and the control unit 13 in the front-to-back direction. The bearing retaining portion 2a includes ribs 2b and a bearing receiving portion 2c. The ribs 2b extend in a lattice-like manner across the inner circumferential surface of the motor housing 2. By forming the ribs 2b in a lattice shape, a plurality of through holes 2d are formed between the inner surface of the motor housing 2 and the bearing receiving portion 2c. That is, the bearing retaining portion 2a has a plurality of through holes 2d that penetrate in the front-to-back direction. In the present embodiment, there are twenty through holes 2d. The bearing receiving portion 2c is supported by the ribs 2b, and receives and retains the bearing 6c. The bearing 6c rotatably supports the rear portion of the rotating shaft 6a of the motor 6. The wiring 6w extending from the stator coil of the motor 6 and the signal line 42w extending from the sensor substrate 40 having a magnetic sensor (Hall element, etc.) for detecting the rotation position of the motor 6 extend backward through the gap (through hole 2d) between the ribs 2b. Although a plurality of through holes 2d are provided, the wiring 6w and the signal line 42w pass through the through holes 2d located at different positions, respectively, thereby suppressing the contact between the wiring 6w and the signal line 42w. In addition, in the present embodiment, there are three wirings 6w, which pass through the through holes 2d located at different positions, respectively. Thus, the position change of the wirings 6w having multiple wires can be restricted, and the contact between the wirings 6w can be suppressed. In addition, the wiring 6w and the signal line 42w pass through the through hole 2d, thereby limiting the movement by the ribs 2b located around them. That is, the wiring 6w and the signal line 42w are limited from useless movement by the bearing retaining portion 2a, so that the connection or assembly of the wiring becomes easy. In the present embodiment, in order to form the through holes 2d, the ribs 2b extending upward, downward, leftward, and rightward are used to form a grid shape, but the through holes can also be formed by a plurality of ribs extending in one direction, for example, a grid shape can also be formed by a plurality of ribs extending upward and downward. In addition, in the present embodiment, the plurality of wirings 6w are configured so that all of them pass through the through holes 2d at different positions, but as long as at least two wirings pass through the through holes 2d at different positions, the above effect can be achieved. In addition, a part of the bearing retaining portion 2a also serves as a plurality of through holes for limiting the movement of the wirings, but a plurality of through holes can also be provided in other positions. The ribs 2b and the through holes 2d are equivalent to the grid portion of the present invention.

[0074] Figure 4 Observed from the rear Figure 3 FIG. 2 is a diagram showing a motor housing 2 in which a control unit 13 is incorporated. The control unit 13 is provided with a switching element or a microcomputer constituting an inverter circuit on the rear side of a control substrate. The wiring 47w is a wiring for supplying electric power to the motor 6 extending from the inverter circuit. Figure 5 Observed from the rear Figure 4FIG. 2 is a diagram showing a state in which a retainer 17 is installed on a motor housing 2. The retainer 17 is a cylindrical shape extending in the front-to-back direction, and is open at the front and rear ends. The retainer 17 has a grid-like rib 17a. By forming a plurality of grid-like ribs 17a in the same manner as the rib 2b, through holes 17c extending in the front-to-back direction are formed. The wiring 6w and the wiring 47w extend toward the rear through the gaps (through holes 17c) between the ribs 17a. The ribs 17a forming a grid-like structure have the effect of limiting the position change of the wiring in the same manner as the ribs 2b. Figure 5 The state is that the wiring 6w and the wiring 47w are not connected, that is, the motor 6 and the control unit 13 are not electrically connected. Figure 5 As shown, the leading ends of the wiring 6w and the wiring 47w before connection are in a state where the insulating material has been removed. Figure 6 The connector 23 is used to connect the Figure 5 The wiring 6w and the wiring 47w are mechanically and electrically connected to each other. Figure 5 The front ends of the wiring 6w and the wiring 47w whose front ends are not insulated are connected to each other. The connection is performed by a method (riveting process) in which pressure is applied to fix the front end portions in a state where they are abutted. The connector 23 is an insulating component included in the electrical connection portion of the wiring 6w and the wiring 47w, that is, the electrical connection portion of the motor 6 and the control unit 13, and partially covers the wiring 6w and the wiring 47w. The connector 23 covers the front ends of the connected wiring 6w and the wiring 47w and their vicinity. In addition, the interior of the connector 23 is constructed in a manner that is equal to or slightly smaller than the size obtained by adding the thickness of the wiring 6w and the wiring 47w, so as to prevent the wiring 6w and the wiring 47w from falling off the connector 23 due to friction or the like. Figure 1 As shown in FIG. 2 , the connector 23 is located outside (at the rear) of the motor housing 2. Specifically, the connector 23 is located inside the handle housing 3. Figure 5 , Figure 6 As shown, the wiring 6w and the wiring 47w are connected to each other after passing through the through holes 17c located at different positions. That is, the final connection line between the motor 6 and the control unit 13 becomes the following shape: it extends from the motor 6, extends to the outside of the motor housing 2, passes through the through hole 17c to the rear, passes over the rib 17a, passes through another through hole 17c to the front, returns to the motor housing 2 and reaches the control unit 13. Therefore, at least a part of the connection line (wiring 6w or 47w) between the motor 5 and the control unit 13 located outside the motor housing 2 is restricted by the rib 17a to move into the motor housing 2. The through hole 17c is equivalent to the fixture through hole of the present invention. In the figure, the lead wire is drawn out from only a part of the through holes 17c. In the present embodiment, there are a total of eight through holes 17c.

[0075] According to the present embodiment, the electrical connection portion (connector 23) between the wiring 6w of the motor 6 and the wiring 47w of the control unit 13 is arranged outside the motor housing 2, so that the electrical connection portion can be prevented from contacting a part of the control unit 13. In particular, even if the switching element or microcomputer, other energized parts, heat sink, etc., which constitute the inverter circuit of the control unit 13, are exposed in the motor housing 2, the risk of the wiring 6w and the wiring 47w being contacted with them and causing a malfunction can be suppressed. In addition, there is no problem in not obtaining a space for arranging the connector 23 in the motor housing 2, so the size of the motor housing 2 can be suppressed, and the flow of cooling air passing in the front-rear direction in the motor housing 2 is not hindered. There is a relatively large space in the handle housing 3 where the connector 23 is located, so there is no problem even if the connector 23 is arranged. In addition, since the connector 23 can be arranged inside the handle housing 3 where there is a large space, a relatively cheap but large connector member can be used, and a cheap electric working machine can be realized. Furthermore, according to the present embodiment, when connecting the wiring 6w and the wiring 47w, the motor 6 and the control unit 13 are both supported by the motor case 2, so relative movement is suppressed. Therefore, the connection operation becomes much easier than when only one is supported.

[0076] (Implementation Method 2) Figure 7 to Figure 12 An electric working machine 1B according to a second embodiment of the present invention will be described. Figure 7 The vertical direction and the front-back direction of the electric working machine 1B are defined. The front-back direction is parallel to the extension direction of the rotating shaft 6a of the motor 6. The electric working machine 1B is a corded grinder operated by power supplied from an external AC power source. The following description will focus on the differences from the first embodiment.

[0077] For connecting to external AC power source 50( Fig.12 ) is extended from the rear end of the handle housing 3. A controller 20 containing an auxiliary power supply-control substrate is provided in the front portion of the handle housing 3. Inlet ports 3a are provided on the left and right sides of the handle housing 3 in the same manner as in the first embodiment. A second switch 12 is provided at a position in front of the trigger 7. The second switch 12 is connected to the handle housing 3. Fig.12 The second switch 12 is electrically connected to the computing unit 21 of the trigger 7, and switches on / off in conjunction with the operation of the trigger 7. The second switch 12 is provided to quickly transmit the operation of the trigger 7 to the computing unit 21, and sends signals of different levels to the computing unit 21 by turning on / off itself. If the user holds the trigger 7, the trigger 7 swings upward, and the second switch 12 is turned on. If the user releases the grip of the trigger 7, the trigger 7 swings downward, and the second switch 12 is turned off.

[0078] The motor housing 2 accommodates the motor 6 and accommodates the bridge inverter board (drive board) 30 at the rear of the motor 6. A structure is provided at the rear of the bridge inverter board 30. Fig.12 The switching element Q of the inverter circuit 47 (corresponding to Fig.12 The bearing holding portion 2a is provided between the motor 6 and the bridge inverter substrate 30, and the bearing holding portion 2a is provided between the motor 6 and the bridge inverter substrate 30, and the bearing holding portion 2a is provided between the motor 6 and the bridge inverter substrate 30, and the bearing holding portion 2a is provided between the motor 6 and the bridge inverter substrate 30.

[0079] The motor 6 is inserted from the front into the motor case 2 for assembly. The bridge inverter board 30 is inserted from the rear into the motor case 2 for assembly. The fixture 17 is fixed to the rear end of the motor case 2 by screwing or the like. Figure 8 The motor housing 2 in which the motor 6 is installed is viewed from the rear. The bearing receiving portion 2c is supported by the rib 2b and receives and holds the bearing. Figure 7 The bearing 28 is provided to rotatably support the rear portion of the rotating shaft of the motor 6. A connector 6n is provided at the front end of the wiring 6w. The connector 6n is a connection part fixed to the front end of the wiring 6w, and the metal part is covered with an insulating material, and can be engaged with a connector 47n described later.

[0080] Fig. 9 Observed from the rear Figure 8 4 is a diagram showing a motor case 2 in which a bridge inverter substrate 30 is installed in a state. Wiring 47w is a wiring extending from an inverter circuit provided on the bridge inverter substrate 30. A connector 47n is provided at the front end of the wiring 47w. The connector 47n is a connection part fixed to the front end of the wiring 47w, and the metal part is covered with an insulating material and can be engaged with the metal part of the connector 6n. Fig.10 Observed from the rear Fig. 9 FIG. 2 is a diagram showing a state where the holder 17 is mounted on the motor housing 2. The wiring 6w and the wiring 47w pass through the gaps (through holes 17c) between the ribs 17a of the holder 17 and extend toward the rear. Fig.11 Observing from the rear Fig.10 The figure shows a state where the connector 6n and the connector 47n are connected to each other and embedded in the recess 17b of the fixture 17. By connecting the connector 6n and the connector 47n to each other, the wiring 6w and the wiring 47w are mechanically and electrically connected to each other. The insulating parts of the connector 6n and the connector 47n partially cover the wiring 6w and the wiring 47w respectively. The interconnected part of the connector 6n and the connector 47n is the electrical connection part of the wiring 6w and the wiring 47w, that is, the electrical connection part of the motor 6 and the bridge inverter substrate 30. As shown in FIG. Fig.10 As shown, the rib 17a has a plurality of recesses 17b. Fig.11As shown, the connector 6n, the connector 47n and the connection portion between the two are fitted and held in the recess 17b. The handle housing 3 may have a rib that presses the connector 6n, the connector 47n and the connection portion between the two held in the recess 17b from behind.

[0081] Fig.12 1 is a circuit diagram of an electric working machine 1B. The AC power supply 50 is an external AC power supply such as a commercial power supply. A filter circuit is connected to the AC power supply 50, and the filter circuit includes a fuse Fin, a varistor Z1, a pattern fuse F1, a capacitor C1, a resistor R1, and a choke coil L1. The fuse Fin is used to protect when the switching element Q1 to the switching element Q6 are short-circuited. The varistor Z1 is used to absorb surge voltage. The pattern fuse F1 has the function of preventing short circuits between lines when the varistor Z1 is working. The capacitor C1 and the choke coil L1 are used to remove noise between lines. The resistor R1 is used to discharge the capacitor C1.

[0082] A first switch 11 is provided between the output side of the filter circuit and the input side of the diode bridge 15. The first switch 11 is a two-pole switch that can open and close both between one output terminal of the filter circuit and one input terminal of the diode bridge 15, and between the other output terminal of the filter circuit and the other input terminal of the diode bridge 15. The diode bridge 15 as a rectifier circuit performs full-wave rectification on the output voltage of the filter circuit input via the first switch 11 to convert it into direct current, and supplies it to the inverter circuit 47. The electrolytic capacitor C2 is used to absorb surges and is provided between the output terminals of the diode bridge 15. The resistor Rs is a detection resistor for detecting the current flowing into the motor 6 and is provided in the current path of the motor 6. The electric working machine 1B has a first ground wire (ground) GND1 and a second ground wire GND2, and the first ground wire GND1 and the second ground wire GND2 are connected to each other via the resistor Rs. The diode bridge 15, the electrolytic capacitor C2, the inverter circuit 47 as the first control unit, and the resistor Rs are provided Figure 7 A bridge inverter substrate 30 is provided.

[0083] The inverter circuit 47 includes switching elements Q1 to Q6 such as insulated gate bipolar transistors (IGBT) or field effect transistors (FET) connected via a three-phase bridge, and performs switching operations according to the control of the operation unit 21 as the second control unit to supply drive current to the stator coil 6e (each winding of U, V, and W) of the motor 6. The operation unit 21 detects the current of the motor 6 through the voltage between the two ends of the resistor Rs. In addition, the operation unit 21 detects the rotation position (rotor rotation position) of the motor 6 through the output voltage of multiple Hall elements (magnetic sensors) 42. The operation unit 21 controls the drive and braking of the motor 6 according to the state (open / closed) of the second switch 12 linked to the operation of the trigger 7. Specifically, when the second switch 12 is turned on by the operation of the trigger 7, the calculation unit 21 applies the drive signals H1 to H6 to the switch elements Q1 to Q6 to perform switch control (e.g., pulse width modulation (PWM) control) to control the drive of the motor 6. When the second switch 12 is turned off by the operation of the trigger 7, the calculation unit 21 performs control (brake control) to apply braking force to the motor 6. The brake control is, for example, a control in which at least one of the lower arm side switch elements Q4 to Q6 is turned on continuously or intermittently while the upper arm side switch elements Q1 to Q3 of the inverter circuit 47 are kept turned off, thereby generating an electric braking force.

[0084] Another diode bridge 16 as a rectifier circuit performs full-wave rectification on the output voltage of the filter circuit input without passing through the first switch 11 to convert it into direct current. The electrolytic capacitor C3 is used to absorb surges and is arranged between the output terminals of the diode bridge 16. An intelligent power device (IPD) circuit 22 is arranged on the output side of the diode bridge 16. The IPD circuit 22 is a circuit including an IPD element or a capacitor as an intelligent power device (Intelligent Power Device), and is a direct current (DC)-DC switching power supply circuit that steps down the voltage rectified and smoothed by the diode bridge 16 and the electrolytic capacitor C3 for absorbing surges to, for example, about 18V. The IPD circuit 22 is an integrated circuit and has the advantages of low power consumption and energy saving. The output voltage of the IPD circuit 22 is further stepped down to, for example, about 5V by the regulator 26, and is supplied to the operation unit 21 as an operating voltage (power supply voltage Vcc). The diode bridge 16, the electrolytic capacitor C3, the calculation unit 21, the IPD circuit 22, the regulator 26 and the like are provided on the auxiliary power supply-control substrate.

[0085] In this embodiment, as in the first embodiment, the electrical connection portion (the interconnection portion between the connector 6n and the connector 47n) between the wiring 6w of the motor 6 and the wiring 47w extending from the bridge inverter substrate 30 is arranged outside the motor housing 2. Therefore, even if the switching elements and other energized parts or the heat sink etc. constituting the inverter circuit of the bridge inverter substrate 30 in the motor housing 2 are exposed, the risk of the wiring 6w and the wiring 47w being contacted with the insulation removal portion and the like and causing a malfunction can be suppressed. In addition, in this embodiment, since the wiring 6w of the motor 6 and the wiring 47w are connected to the front portion ( Figure 1 Although there is no space in the front of the handle housing 3, the connector 6n, the connector 47n and the interconnected parts of the two are embedded and held in the recessed part 17b of the rib 17a of the holder 17, so that the connector 6n, the connector 47n and the interconnected parts of the two can be appropriately located outside the motor housing 2. In addition, since the connector 6n, the connector 47n and the interconnected parts of the two are fixed to the holder 17, the position of the interconnected parts will not be shifted due to vibration during operation or cooling wind from the air intake port 3a to the air exhaust port 4a. As a result, it is possible to suppress the contact between different interconnected parts or the blockage of the air path.

[0086] The present invention has been described above by taking the embodiments as examples, but it is understood by those skilled in the art that various modifications may be made to the components or processes of the embodiments within the scope of the claims.

[0087] The electric working machine of the present invention may be an electric working machine other than the grinding machine exemplified in the embodiment, and is particularly suitable for an electric working machine having a motor case of a cylindrical integral structure that is molded in an indivisible manner.

Claims

1. An electric working machine, characterized in that: include a motor housing, the motor housing supporting the motor and a first control unit controlling the motor; Motor-side wiring extending rearward from the motor; Control unit side wiring extending rearward from the first control unit; as well as A retainer, connected to the rear of the motor housing, The first control unit is located behind the motor. The holder is located behind the first control unit. The fixture is provided with a plurality of fixture through holes, and the motor side wiring is inserted through one of the plurality of fixture through holes, and the control unit side wiring is inserted through one of the plurality of fixture through holes. The motor-side wiring and the control-unit-side wiring are connected via an electrical connection portion that is located outside the motor housing and behind the first control unit.

2. The electric working machine according to claim 1, characterized in that: The electrical connection portion is formed by connecting and fixing the front end of the motor-side wiring and the front end of the control-part-side wiring.

3. The electric working machine according to claim 2, characterized in that: The electrical connection portion includes a connector that at least partially covers the motor-side wiring and the control-part-side wiring that are connected.

4. The electric working machine according to claim 3, characterized in that: The connector is a connection component in which a metal portion is covered with an insulating material and is fixed to the front end of the motor.

5. The electric working machine according to claim 3 or 4, characterized in that: The fixture is provided with lattice-shaped ribs, The plurality of fixture through holes are formed by the ribs, The control unit side wiring is inserted into the fixture through hole located at a position different from the fixture through hole through which the motor side wiring passes, and at least a portion of the motor side wiring and at least a portion of the control unit side wiring are restricted by the rib from moving into the motor housing.

6. The electric working machine according to claim 3 or 4, wherein: The fixture is provided with lattice-shaped ribs, The plurality of fixture through holes are formed by the ribs, The rib has a recessed portion in which the connector is inserted and retained.

7. The electric working machine according to claim 3 or 4, characterized in that: A gear box is connected to one side of the motor housing. The electrical connection portion is located on the other side than the motor housing.

8. The electric working machine according to claim 7, characterized in that: A handle housing is provided on the other side of the motor housing. The electrical connection portion is located inside the handle housing.

9. The electric working machine according to claim 8, characterized in that: A second control unit for controlling the first control unit is accommodated inside the handle housing.

10. The electric working machine according to claim 9, characterized in that: The handle housing is held by the motor housing via the holder.

11. The electric working machine according to claim 10, characterized in that include: a fan, rotated by the motor; as well as an air intake and an air exhaust port for generating a flow of air for cooling the motor by the rotation of the fan; The air flowing in from the air intake port passes through the fixture through-hole and then flows into the motor housing.

12. The electric working machine according to claim 3 or 4, characterized in that: In the motor housing, a plurality of through holes are formed by a plurality of ribs extending from an inner surface of the motor housing. The motor-side wiring passes through the through hole and is connected to the control-part-side wiring.

13. The electric working machine according to claim 12, characterized in that: There are multiple motor-side wirings. At least two of the plurality of motor-side wires are passed through the through holes at different positions, respectively.

14. The electric working machine according to claim 12, characterized in that: A bearing holding portion for holding a bearing is located between the motor and the first control portion, the bearing supporting a rotating shaft of the motor, The through hole is provided in the bearing holding portion.

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