CN111446782A

CN111446782A - Special-shaped stator brushless motor and electric tool thereof

Info

Publication number: CN111446782A
Application number: CN202010341158.0A
Authority: CN
Inventors: 赵乾麟; 柳文; 周群; 赵屹; 管秀玉; 黄乾利; 方炳平; 程睛
Original assignee: Zhejiang Cheering Sewing Machine Co ltd
Current assignee: Zhejiang Cheering Sewing Machine Co ltd
Priority date: 2020-04-27
Filing date: 2020-04-27
Publication date: 2020-07-24

Abstract

The invention discloses a special-shaped stator brushless motor consisting of a shell, a stator and a rotor, and an electric tool thereof. The motor is characterized in that the stator of the motor adopts axis offset, so that the rotor of the motor is in an eccentric position, and the distance from the bottom of the motor shell to a processing surface is increased. The disc cutter assembled by the motor has the advantages that the blade tip has the relative maximum distance with the bottom of the motor, so that the cutting depth of the blade is increased, and the maximum efficiency of the product provided by the invention can be realized under the condition of using a limited power model.

Description

Special-shaped stator brushless motor and electric tool thereof

Technical Field

The present invention relates to a motor, and more particularly, to a brushless motor and a power tool having the same.

Background

An electric motor is a power machine widely used in various fields. In recent years, brushless dc motors have been developed rapidly and are widely used in various aspects of social life because of their high efficiency and energy saving. In the application aspect of the electric tool, particularly the application aspect of the disc type electric cutting machine, the direct-current brushless motor can provide low-speed and high-torque power, so that the disc type electric cutting machine can directly drive a sheet by using a motor shaft, a gear reduction transmission link of the cutting machine is omitted, the structure of the disc type electric cutting machine is greatly simplified, the working noise of the electric cutting machine is obviously reduced, and the working efficiency is improved. However, because the size of the motor housing is limited by the size of the stator diameter of the motor, the disc of the cutting knife is perpendicular to the axial direction of the motor housing in the direct-drive type electric disc cutting machine, and therefore the cutting depth of the cutting knife is limited by the diameter of the motor stator, which affects the application range of the motor cutting machine with limited power.

Disclosure of Invention

In order to solve the problem of the cutting depth of the disc cutting knife, the invention provides a novel design of a special motor capable of improving the cutting depth of the disc cutting knife by improving the structural form of a driving motor.

The invention is realized by the following modes: a brushless motor with special-shaped stator is composed of casing, stator consisting of iron core and winding, and rotor in said casing.

Furthermore, the stator of the motor is formed by distributing 3N times of iron cores in a circumference manner, the iron cores are in an I shape, the upper end and the lower end of the I shape are coaxial arcs, the lower arcs of the iron cores are connected to form a circular tube shape, a motor rotor is arranged in the motor, coil windings are arranged on the iron cores, the iron cores are in A, B, C types, wherein the upper end and the lower end of the I shape of the A type iron core are concentric, the upper end and the lower end of the I shape of the B type iron core are not concentric, the circle center of the I shape of the B type iron core is kept on the straight line of the middle point of the iron core, the circle center of the lower end of the I shape of the C type iron core is concentric with a rotor shaft, the circle center of the upper end of the arc deviates from the straight line of the middle point of the iron core, the upper end of the I shape of the B, C type iron core is the same, the stator of the motor is formed by circumferentially distributing 3N times of iron cores, the iron cores are in I shapes, the upper ends and the lower ends of the I shapes are coaxial arcs, the lower arcs of the iron cores are connected to form a circular tube shape, a motor rotor is arranged in the circular tube shape, and coil windings are arranged on the iron cores.

The invention improves the stator structure of the driving motor, so that the rotor of the motor is in an eccentric position, and the distance between the rotor shaft and the edge of the motor shell is reduced. When the power-driven cutter is used for providing power for the electric cutter, the distance between the tip of the blade and the lower part of the motor can be effectively increased, so that the cutting depth of the blade is increased, and the application range of the product provided by the invention can be expanded under the condition of using a limited power model.

The present invention is described in further detail below with reference to the attached drawings.

Drawings

FIG. 1 is a schematic cross-sectional view showing the structure of example 1 of the present invention;

FIG. 2 is a schematic cross-sectional view showing the structure of embodiment 2 of the present invention;

FIG. 3 is a schematic view of a class A core structure;

FIG. 4 is a schematic view of a class B core structure;

FIG. 5 is a schematic view of a class C core structure;

fig. 6 is a combination diagram of A, B types of stator cores in embodiment 3;

fig. 7 is a combination diagram of A, C-type stator cores in embodiment 4;

fig. 8 is a schematic structural view of a motor disc cutter according to embodiment 6 of the present invention.

In the figure, 1, a motor shell; 2. a rotor; 3. a stator; 4. a class A core; 5. a class B core; 6. a class C core; 41. the upper end of the A-type iron core; 42. the lower end of the class A iron core; 51. the upper end of the B-type iron core; 52. the lower end of the B-type iron core; 61. the upper end of the C-type iron core; 62. The lower end of the C-type iron core.

Detailed Description

Example 1: the special-shaped stator brushless motor is formed by a motor shell 1, a stator 3 and a rotor 2 which are arranged in the motor shell 1, wherein the special-shaped stator is formed by punching silicon steel sheets according to the shape shown in figure 1 to form nine iron cores which are distributed in a circumferential manner and have different shapes, the circumferential center of each iron core deviates from the center of the outer circle of the stator 3, and the rotor 2 is arranged in the circumferential center of each iron core to enable the rotor 2 to be located at the eccentric position of the stator 3 with the outer periphery being circular or elliptical.

The iron cores are stacked to form an iron core of a coil winding of the stator 3, and the coil winding is formed by winding a wire on the iron core. The rotor is adhered with magnetic steel, so that the matching relation between the stator 3 and the rotor 2 is formed. The coil windings are divided into three groups which are connected in series, and the three groups of coils are mutually spaced. After the coil winding is connected with a driving power supply, a rotating magnetic field can be formed to push the rotor to rotate.

When the motor is used for providing power for the electric cutting machine, the disc cutting knife can be directly installed on a main shaft of the motor, and the offset direction of the axis of the stator 3 of the motor is the maximum depth direction of cutting, so that the using effect of the electric cutting machine is improved.

Example 2: as shown in fig. 2, a brushless motor with a special-shaped stator is composed of a motor housing 1, a stator 3 and a rotor 2 which are installed in the motor housing 1, wherein the stator 3 of the motor is formed by 9 iron cores which are distributed in a circumferential manner, the iron cores are i-shaped and are divided into A, B, C types, which are respectively shown in fig. 3, 4 and 5, wherein the arcs of the i-shaped upper end 41 and the i-shaped lower end 42 of the a-type iron core 4 are concentric, the arcs of the upper end 51 and the lower end 52 of the i-shaped B-type iron core 5 are not concentric, the center of the arc is kept on the straight line of the midpoint of the iron core, and the radius of the arc of the upper end 51 of the i-shaped i-.

The circle center of the I-shaped lower end 62 arc of the C-type iron core 6 is concentric with the axis of the rotor 2, and the circle center of the upper end 61 arc deviates from the straight line of the middle point of the iron core, so that the I-shaped upper and lower end arcs of the C-type iron core 6 are in an open shape, namely, one end is small and the other end is large, and the radius of the arc of the upper end 61 is the same as the radius of the arc of the upper end 51 of the B-type iron core 5, thus ensuring that the upper end arc of the B, C is in a continuous.

A. B, C the three types of iron cores are distributed in circumference, the lower end arcs of the iron cores are connected to form a circular tube shape, the upper end of the iron cores is in a cam shape, the casing of the motor can form a cam shape along the section vertical to the axial direction of the rotor 2 according to the shape of the stator, the motor rotor 2 is placed in the circular tube formed by connecting the lower end arcs of the iron cores, and the iron cores are provided with coil windings, thus forming the special-shaped stator brushless motor.

Example 3: the brushless motor with the special-shaped stator shown in fig. 2 comprises a motor housing 1, a stator 3 and a rotor 2 which are arranged in the housing 1, wherein the stator 3 is composed of three stator cores, the three stator cores are composed of two stator cores 3 of type a and one stator core 4 of type B (as shown in fig. 6), and other implementation processes are the same as those in embodiment 2.

Example 4: the special-shaped stator brushless motor shown in fig. 2 is composed of a motor housing 1, a stator and a rotor 2 which are installed in the motor housing, six stator cores form a stator winding frame of the motor, the six stator cores are composed of two a-type stator cores 4 and two C-type stator cores 5 (as shown in fig. 7), and other implementation processes are the same as those of the embodiment 2.

Example 5: the invention also provides a motor, and an electric appliance comprises the motor.

Example 6: the invention also provides an electric tool which comprises the motor.

Further, the electric tool is a disc cutter. As shown in fig. 8, after the disc cutting machine adopts the motor technology shown in the technical scheme, the structure is very simple, only one handle is arranged on the shell 1 of the motor, and the disc blade 6 arranged on the main shaft of the motor can be completed. It should be noted that the disc cutting machine directly drives the blade to rotate through the motor, and the casing diameter of the motor directly affects the feed depth of the cutting machine. In brushless motors, the output power of the motor depends on the number of coil winding turns of the motor, which determines the diameter of the motor's housing. Therefore, under the same output power condition, the diameter of the disc cutter is directly limited by the diameter of the motor, so that the radius of the bottom of the motor is reduced, the cutting depth of the cutter can be effectively improved, and the service efficiency and the application range of the disc cutter are improved.

The invention is not limited to use on a disc cutter. The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims

1. A brushless motor with special-shaped stator is composed of casing, stator consisting of iron core and winding, and rotor in said casing.

2. The irregular stator brushless motor according to claim 1, wherein the stator of the motor is formed by 3N times of iron cores distributed in a circumference shape, the iron cores are i-shaped, the upper and lower ends of the i-shaped iron cores are coaxial arcs, the lower arcs of the iron cores are connected to form a circular tube shape, a motor rotor is embedded in the circular tube shape, coil windings are arranged on the iron cores, the iron cores are A, B, C types, wherein the H-shaped upper and lower end arcs of the class A iron core are concentric, the H-shaped upper and lower end arcs of the class B iron core are not concentric, the center of the circle is kept on the center point straight line of the iron core, the center of the circle of the H-shaped lower end arc of the C-type iron core is concentric with the rotor shaft, the center of the upper end arc deviates from the straight line of the center point of the iron core, the center of the upper end arc of the B, C class iron core I shape is the same as the center of the center, and the A, B, C class winding coils are distributed circumferentially to form the cam-shaped stator.

3. A power tool, characterized in that it comprises a motor according to claims 1-2.

4. The power tool of claim 3, wherein the power tool is a power disc cutter.