Motor and electric tool

Abstract

The utility model discloses a motor and an electric tool. The motor comprises a motor shaft; the rotor assembly is sleeved on the motor shaft; the stator assembly is arranged around the motor shaft, the stator assembly comprises a stator iron core, a stator end plate connected with the stator iron core and a plurality of groups of coils wound on the stator end plate, and a plurality of wiring structures are arranged on one side, far away from the stator iron core, of the stator end plate along the circumferential direction of the motor shaft; each wiring structure comprises a first connecting part and a second connecting part which are oppositely arranged at an interval; the jumper wire is connected with different groups of coils through the first connecting part; and the outgoing line is connected with the coil and is led out of the stator assembly through the second connecting part. The circumferential layout of the wiring structure saves axial space and is suitable for a compact electric tool motor cabin; and compared with a built-in wiring structure, the assembled structure is high in stability.

Description

Technical Field

[0001] This application relates to the field of tool technology, and in particular to an electric motor and a power tool. Background Technology

[0002] There are two main wiring methods for the stator coils of brushless motors used in power tools. The first method is without terminals, where the enameled wire is directly connected to the lead wires. The second method uses terminals to connect the stator coils and lead wires.

[0003] There are two types of terminal block fixing methods: one is that the terminal block is on the outer circumference of the stator core; the other is that the terminal block is fixed to the end plate on the axial side of the stator core, and the lead wire is welded to the terminal welding part. However, most of the existing terminal welding parts are suspended outside, which can easily affect the structural stability of some tools with large vibrations.

[0004] Therefore, the stator coil wiring of traditional brushless motors often adopts decentralized welding or external terminal blocks, which has problems such as low space utilization, complex assembly process, and susceptibility to mechanical vibration. Utility Model Content

[0005] To address the shortcomings of existing technologies, this application provides an electric motor and power tool that can improve the space utilization and stability of the wiring structure.

[0006] This application provides an electric motor, including:

[0007] Motor shaft;

[0008] The rotor assembly is mounted on the motor shaft;

[0009] A stator assembly is arranged around the motor shaft. The stator assembly includes a stator core, a stator end plate connected to the stator core, and multiple sets of coils wound on the stator end plate. Multiple wiring structures are arranged circumferentially along the motor shaft on the side of the stator end plate away from the stator core. Each wiring structure includes a first connection part and a second connection part arranged at relative intervals.

[0010] A jumper wire is used to connect different groups of coils via the first connecting part;

[0011] The lead wire is connected to the coil and led out through the second connection part to the outside of the stator assembly.

[0012] A further improvement is proposed: the motor is a three-phase brushless motor, and the stator assembly includes three sets of coils and three wiring structures.

[0013] A further improvement is that the adjacent wiring structures are distributed on the stator end plate at 120° intervals along their circumference.

[0014] A further improvement is that the wiring structure is distributed within the same half-circumference of the stator end plate in the circumferential direction.

[0015] A further improvement is as follows: the wiring structure further includes a main body, and the first connecting part and the second connecting part respectively include a first bottom and a second bottom connected to the main body, and the first bottom and the second bottom are curved.

[0016] A further improvement is as follows: the first connecting portion further includes a first head portion opposite to the first bottom, and the second connecting portion further includes a second head portion opposite to the second bottom, wherein the first head portion is higher than the second head portion.

[0017] A further improvement is that the bending angle of the first bottom is greater than that of the second bottom.

[0018] A further improvement is as follows: barbs are provided on both sides of the main body, and the wiring structure is fixed to the stator end plate by the barbs;

[0019] The outer peripheral surface of the stator end plate is provided with a wire-holding groove, and the lead wire is led out to the outside of the stator assembly through the second connecting part and the wire-holding groove in sequence.

[0020] A further improvement is as follows: the jumper wire is welded and fixed to the first connecting part, and the lead wire is welded and fixed to the second connecting part.

[0021] This application provides an electric tool, including the aforementioned motor.

[0022] The motor and power tool provided in this application have a circumferential wiring structure that saves axial space and is suitable for compact power tool motor compartments; the relatively built-in wiring structure makes the assembled structure more stable; the centralized wiring of jumper wires and leads in the wiring structure reduces the coil assembly process, while the separate connection part design realizes the physical isolation of jumper wires and leads, avoiding the risk of short circuit caused by cable interference. Attached Figure Description

[0023] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0024] Figure 1 These are perspective views of the motors provided in some embodiments of this application;

[0025] Figure 2 This is a perspective view of a stator assembly provided in some embodiments of this application;

[0026] Figure 3 This is a perspective view of the stator end plate provided in some embodiments of this application;

[0027] Figure 4 This is a perspective view of the wiring structure provided in some embodiments of this application;

[0028] Figure 5 This is a front view of the wiring structure provided in some embodiments of this application. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable readers to better understand this application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in this application can be implemented. The division of the various embodiments below is for the convenience of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0031] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0032] like Figures 1 to 5As shown, some embodiments of this application provide a motor including a motor shaft 100, a rotor assembly 200, a stator assembly 300, a jumper wire 400, and a lead wire 500. The rotor assembly 200 is mounted on the motor shaft 100, and the stator assembly 300 is arranged around the motor shaft 100. The stator assembly 300 includes a stator core 310, a stator end plate 320 connected to the stator core 310, and multiple sets of coils 330 wound on the stator end plate 320. Multiple wiring structures 340 are arranged circumferentially along the motor shaft 100 on the side of the stator end plate 320 away from the stator core 310. Each wiring structure 340 includes a first connecting portion 341 and a second connecting portion 342 arranged at relative intervals. The jumper wire 400 connects different sets of coils 330 via the first connecting portion 341, and the lead wire 500 is connected to the coil 330 and led out to the outside of the stator assembly 300 via the second connecting portion 342.

[0033] The stator end plate 320 is generally annular, and the wiring structures 340 are arranged circumferentially on the stator end plate 320. The circumferential arrangement of multiple wiring structures 340 can reduce the waste of axial space when arranged centrally or axially, and is more suitable for the motor compartment of compact power tools. The wiring structures 340 are not external to the stator end plate 320, and the relatively built-in wiring structures 340 enhance the structural stability after assembly. Each wiring structure 340 includes a first connection part 341 for connecting the jumper wire 400 and a second connection part 342 for connecting the lead wire 500. The centralized wiring of the jumper wire 400 and the lead wire 500 in the wiring structure 340 reduces the assembly steps of the coil 330 group. The first connection part 341 and the second connection part 342 are arranged at intervals, making the connection part a split design, realizing the physical isolation between the jumper wire 400 and the lead wire 500, and avoiding the risk of short circuit caused by cable interference.

[0034] The motor shaft 100 is the power output part of the motor, which can be connected to the actuator of the power tool to transmit the driving force and motion generated by the motor to the end effector to realize the corresponding machining operation. The motor shaft 100 is fixedly connected to the rotor assembly 200 and can rotate synchronously with the rotor assembly 200. The motor shaft 100 has a certain length and can be connected to the input end of the transmission mechanism in the power tool.

[0035] The rotor assembly 200 is the rotatable part of the motor. The rotor assembly 200 includes magnets, which are fixed to the inner wall of the end cover or embedded in the mounting slot of the rotor core, forming an external rotor motor or an internal rotor motor. The rotor assembly 200 can rotate under the magnetic field generated by the stator assembly 300, thereby driving the motor shaft 100 to rotate synchronously.

[0036] The stator assembly 300 is the stationary part of the motor. A housing can be installed around the stator assembly 300 for protection. The stator assembly 300 includes a stator core 310, a stator end plate 320, and coils 330. The stator core 310 is not only a key part of the motor's magnetic circuit but also serves to fix and support the coils 330. The coils 330 can be connected to an external circuit via leads 500, and the cable ends can be electrically connected via wiring structures 340. When current flows through the coils 330, the generated magnetic field is collected and concentrated in the stator core 310, thereby amplifying and guiding it to the rotor assembly 200, driving the rotor assembly 200 to rotate. The stator end plate 320 provides electrical isolation between the stator core 310 and the coils 330, and provides winding support for the coils 330. The stator assembly 300 as a whole is rotatably connected to the motor shaft 100.

[0037] In one embodiment, the motor is a three-phase brushless motor, and the stator assembly 300 includes three sets of coils 330 and three wiring structures 340. Specifically, the stator assembly 300 of the three-phase brushless motor includes three sets of coils 330 (U / V / W phases) distributed symmetrically at 120°, and each set of coils 330 corresponds to an independent wiring structure 340. The wiring structure 340 uses a first connecting part 341 to receive a jumper wire 400 to realize the connection between UV, VW, and WU phases. A second connecting part 342 fixes the lead wires 500, and the three lead wires 500 are led out through the wire clamping groove 321 on the outer periphery of the stator end plate 320, for example, to a junction box.

[0038] In one embodiment, adjacent wiring structures 340 are distributed on the stator end plate 320 at circumferential intervals of 120°. In another embodiment, the wiring structures 340 are distributed within the same half-circumference of the stator end plate 320. The symmetrical 120° equidistant distribution is suitable for tools requiring high symmetry, including high-power tools such as hammer drills and cutting machines that require balanced output; the semi-circular concentrated distribution within a 180° range is suitable for compact tools with limited space, such as angle grinders.

[0039] Furthermore, when the wiring structures 340 are distributed within the same half-circumference of the stator end plate 320, the center angle interval between adjacent wiring structures 340 is limited to 35°-45°, for example, 35°, 40°, or 45°, to facilitate the concentration of the lead wires 500 and the provision of a centralized heat dissipation duct, thereby reducing the temperature rise of the motor and corresponding power tools. Preferably, the center angle interval between adjacent wiring structures 340 is 40°.

[0040] In one embodiment, the wiring structure 340 further includes a main body 343. The first connecting portion 341 and the second connecting portion 342 respectively include a first bottom 3411 and a second bottom 3421 connected to the main body 343. The first bottom 3411 and the second bottom 3421 are curved. The included angle formed by the inner side of the first bottom 3411 after bending is greater than the included angle formed by the inner side of the second bottom 3421 after bending. Specifically, the included angle formed by the inner side of the first bottom 3411 after bending, i.e., the bending angle, is 35°-85°, for example, 35°, 60°, or 85°; the included angle formed by the inner side of the second bottom 3421 after bending, i.e., the bending angle, is 15°-65°, for example, 15°, 40°, or 65°. The curved first bottom 3411 and the second bottom 3421 are used to directly guide and limit the crossover line and the lead-out line 500, and facilitate the welding process. In addition, the curved bottom can match the arc-shaped guide groove of the automated welding fixture to improve positioning accuracy; the double-bottom differentiated bending also makes it easier for the visual recognition system to distinguish between the welding stations of jumper wire 400 and lead wire 500.

[0041] In one embodiment, the first connecting portion 341 further includes a first head portion 3412 opposite to the first bottom portion 3411, and the second connecting portion 342 further includes a second head portion 3422 opposite to the second bottom portion 3421, with the first head portion 3412 being higher than the second head portion 3422. The higher position of the first head portion 3412 creates a stepped layout between the first connecting portion 341 and the second connecting portion 342, providing spatial isolation between the jumper wire 400 and the lead wire 500, facilitating hierarchical gripping by automated equipment, and improving assembly efficiency. Furthermore, the relatively high position arrangement keeps the corresponding jumper wire 400 further away from the stator core 310, reducing eddy current losses.

[0042] In one embodiment, barbs 3431 are provided on both sides of the main body 343, and the wiring structure 340 is fixed to the stator end plate 320 by the barbs 3431. Corresponding grooves that mate with the barbs 3431 can be provided on the stator end plate 320. Specifically, three pairs of barbs 3431 can be provided on both sides of the main body 343. The barbs 3431 make the wiring structure 340 more stable and less prone to movement or damage.

[0043] To further improve the stability of the jumper wire 400 and the lead wire 500, fix their relative positions, and prevent wire breakage caused by vibration, the outer peripheral surface of the stator end plate 320 is also provided with a wire clamping groove 321. The lead wire 500 is led out to the outside of the stator assembly 300 through the second connecting part 342 and the wire clamping groove 321 in sequence; the jumper wire 400 is welded and fixed to the first connecting part 341, and the lead wire 500 is welded and fixed to the second connecting part 342.

[0044] Some embodiments of this application also provide a power tool, which includes the aforementioned motor. The power tool can be a common handheld power tool, such as an electric screwdriver, electric grinder, or electric reciprocating saw. The power tool can also be a larger, push-type tool, such as a lawnmower. The actuating components of the power tool are driven by a motor to perform the corresponding processing operations.

[0045] Those skilled in the art will understand that the above embodiments are specific implementations of this application, and in practical applications, various changes can be made in form and detail without departing from the spirit and scope of this application.

Claims

1. An electric motor, characterized in that, include: Motor shaft; The rotor assembly is mounted on the motor shaft; A stator assembly is arranged around the motor shaft. The stator assembly includes a stator core, a stator end plate connected to the stator core, and multiple sets of coils wound on the stator end plate. Multiple wiring structures are arranged circumferentially along the motor shaft on the side of the stator end plate away from the stator core. Each wiring structure includes a first connection part and a second connection part arranged at relative intervals. A jumper wire is used to connect different groups of coils via the first connecting part; The lead wire is connected to the coil and led out through the second connection part to the outside of the stator assembly.

2. The motor according to claim 1, characterized in that: The motor is a three-phase brushless motor, and the stator assembly includes three sets of coils and three wiring structures.

3. The motor according to claim 2, characterized in that: The adjacent wiring structures are distributed on the stator end plate at circumferential intervals of 120°.

4. The motor according to claim 2, characterized in that: The wiring structure is distributed within the same half-circumference of the stator end plate in the circumferential direction.

5. The motor according to claim 1, characterized in that: The wiring structure also includes a main body, and the first connecting part and the second connecting part respectively include a first bottom and a second bottom connected to the main body, and the first bottom and the second bottom are curved.

6. The motor according to claim 5, characterized in that: The first connecting portion further includes a first head portion opposite to the first bottom portion, and the second connecting portion further includes a second head portion opposite to the second bottom portion, wherein the first head portion is higher than the second head portion.

7. The motor according to claim 5, characterized in that: The first bottom has a greater bending angle than the second bottom.

8. The motor according to claim 5, characterized in that: The main body has barbs on both sides, and the wiring structure is fixed to the stator end plate by the barbs; The outer peripheral surface of the stator end plate is provided with a wire-holding groove, and the lead wire is led out to the outside of the stator assembly through the second connecting part and the wire-holding groove in sequence.

9. The motor according to claim 1, characterized in that: The jumper wire is welded and fixed to the first connection part, and the lead wire is welded and fixed to the second connection part.

10. A power tool, characterized in that, Includes the motor as described in any one of claims 1 to 9.

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