CROSS-REFERENCE TO RELATED DISCLOSURE

This application is a U.S. National Stage of International Application No. PCT/CN2017/119434, filed on Dec. 28, 2017, and published as WO 2019/029109 on Feb. 14, 2019, which claims priority to the Chinese Application No. 201710676617.9, titled “Tangential Motor, Tangential Motor Rotor and Rotor Iron Core Thereof”, filed on Aug. 9, 2017. Each application, publication, and patent listed in this paragraph are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates to the technical field of motor equipment, and in particular, to a tangential motor, a tangential motor rotor, and a rotor iron core thereof.

BACKGROUND

As the tangential permanent magnet synchronous motor has the effect of “flux concentration”, compared with the radial permanent magnet synchronous motor, the tangential permanent magnet synchronous motor can generate a higher air-gap magnetic flux density, which makes the motor have such advantages as a small size, a light weight, a large torque, a larger power density, high efficiency and good dynamic performance, etc. More and more tangential permanent magnet synchronous motors are applied in industrial fields such as servo systems and electric traction, and in household electric appliances.

At present, the air gap magnetic flux density and the counter electromotive force of the tangential permanent magnet synchronous motor contain various types of spatial harmonic waves. The stator of the tangential permanent-magnet synchronous motor is provided with slots, therefore the magnetic permeability of the magnetic circuit is uneven, and the air gap magnetic flux density and the counter electromotive force of the tangential permanent magnet synchronous motor contain various types of spatial harmonic waves, and the proportion of the harmonic waves is large. The interaction of various harmonic waves generates low-order force waves, which increases the vibration noise of the motor. The waveform has poor sine degree and a high distortion rate, thus making the motor's vibration and noise larger. The permanent magnets of the tangential permanent magnet motor are a parallel magnetic circuit structure, therefore the permanent magnet is prone to be caused a lower operating point and prone to be demagnetized under severe working conditions, which limits the application and popularization of the motor. In addition, the rotor iron core includes rotor punched segments, and the flux isolating holes in them are likely to cause a low mechanical strength.

Therefore, how to improve the mechanical strength and reduce the vibration noise of the motor is a problem to be solved urgently by those skilled in the art.

SUMMARY

In view of this, the present disclosure provides a rotor iron core to improve the mechanical strength and reduce the vibration noise of the motor. The present disclosure also provides a tangential motor rotor having the rotor iron core, and a tangential motor.

To achieve the above purpose, the present disclosure provides the following technical solutions:

a rotor iron core, including a rotor body and permanent magnet slots disposed on the rotor body; a fixing hole for fixing a rotor punched segment and a flux isolating hole are disposed on a rotor magnetic pole between two adjacent permanent magnet slots; the flux isolating hole is disposed outside the fixing hole in a radial direction of the rotor body; and a width of the flux isolating hole smoothly increases in a direction from an outer side of the rotor body toward a center thereof.

In an embodiment, in the above rotor iron core, the fixing hole and the flux isolating hole are both disposed on a center line of a magnetic pole of each of the permanent magnet slots.

In an embodiment, in the above rotor iron core, an outside wall of the flux isolating hole is a curved surface concentrical with the rotor body, and the outside wall of the flux isolating hole is adjacent to the outer side of the rotor body;

a first flux barrier is formed between the outside wall of the flux isolating hole and an outer wall of the rotor body; a width of the first flux barrier is C; the rotor iron core engages with a stator through an air gap, and a length of the air gap is D;
2.4≥C/D≥0.4.
In an embodiment, in the above rotor iron core, 1.5≥C/D≥0.7.

In an embodiment, in the above rotor iron core, the flux isolating hole is an axisymmetric structure, and an extension of a symmetry axis passes through a center of the rotor body.

In an embodiment, in the above rotor iron core, a width of an outside wall of the flux isolating hole is A, and an angle occupied by a single magnetic pole of the rotor iron core is B;
0.15≥A/B≥0.02.

In an embodiment, in the above rotor iron core, an angle formed by two lines respectively connecting a center of the rotor body and each of two end points G of an inside wall of the flux isolating hole is E;
60°≥E≥40°.

In an embodiment, in the above rotor iron core, a length of the flux isolating hole in the radial direction of the rotor body is F, and a radius of the rotor body is R;
0.4≥F/R≥0.1.

In an embodiment, in the above rotor iron core, a minimum distance of an entity portion between the flux isolating hole and the fixing hole is greater than 1.5 mm;

and/or, a minimum distance of an entity portion between the flux isolating hole and each of the permanent magnet slots is greater than 1.5 mm.

In an embodiment, in the above rotor iron core, an inside wall of the flux isolating hole is provided with a protrusion protruding toward an outer side of the rotor body, and the inside wall of the flux isolating hole is adjacent to a center of the rotor body.

In an embodiment, in the above rotor iron core, a vertex of the protrusion and a center line of the flux isolating hole intersect at an intersection M, and a distance from the intersection M to an outside wall of the flux isolating hole is H, and in the radial direction of the rotor body, a length of the flux isolating hole is F;
0.5≥H/F≥0.3.

In an embodiment, in the above rotor iron core, an inside wall of the flux isolating hole is provided with a concave groove, and the inside wall of the flux isolating hole is adjacent to a center of the rotor body, and the concave groove faces away from the outer side the rotor body.

In an embodiment, in the above rotor iron core, the concave groove is a sharp-pointed groove or a curved groove;

a vertex of the concave groove and a center line of the flux isolating hole intersect at an intersection M; a distance from the intersection M to an outside wall of the flux isolating hole is H, and the outside wall of the flux isolating hole is away from the center of the rotor body is H; and in the radial direction of the rotor body, a length of the flux isolating hole without the concave groove is F;
1.4≥H/F>1.

In an embodiment, in the above rotor iron core, an inside wall of the flux isolating hole is a plane, and the inside wall of the flux isolating hole is adjacent to the center of the rotor body.

In an embodiment, in the above rotor iron core, each of the permanent magnet slots has an opening facing toward the outside of the rotor body, and a width of the opening is greater than half of a width of each of the permanent magnet slots.

In an embodiment, in the above rotor iron core, a maximum width of the flux isolating hole is more than twice a minimum width thereof;

and/or, a maximum width of the flux isolating hole is more than 1.5 times a diameter of the fixing hole.

The present disclosure further provides a tangential motor rotor, including a rotor iron core and tangentially magnetized permanent magnets disposed in permanent magnet slots, the rotor iron core is any one of the rotor iron cores.

In an embodiment, in the above tangential motor rotor, a first width of the tangentially magnetized permanent magnet is larger than a second width thereof, and the first width is adjacent to an outer side of the rotor iron core, and the second width is adjacent to a center of the rotor iron core.

The present disclosure further provides a tangential motor, including a tangential motor rotor and a stator, the tangential motor rotor is any one of the tangential motor rotors.

In an embodiment, in the above tangential motor, the stator has stator slots and slot openings facing an air gap between the tangential motor rotor and the stator; a width of each of the slot openings is K; a width of an outside wall of the flux isolating hole of the rotor iron core of the tangential motor rotor is A;
1.2≥A/K≥0.8.

As can be seen from above solutions, in the rotor iron core provided in the present disclosure, the fixing hole and the flux isolating hole are disposed on the rotor magnetic pole; the flux isolating hole is disposed outside the fixing hole in the radial direction of the rotor body. Through providing the fixing hole and providing a fixing member in the fixing hole, the mechanical strength of the rotor is effectively improved. Moreover, the width of the flux isolating hole smoothly increases in the direction from the outer side of the rotor body toward a center thereof, thereby effectively improving the magnetic flux direction of the rotor magnetic pole, increasing the air-gap magnetic flux density and the sine degree of the counter electromotive force, reducing the proportion of harmonic waves and the harmonic wave loss, reducing the vibration noise of the motor, and increasing the efficiency of the motor.

The present disclosure further provides the tangential motor rotor having the rotor iron core above, and the tangential motor. Since the above rotor iron core has the above technical effects, the tangential motor rotor having the above rotor iron core and the tangential motor should also have the same technical effects, which will not be described repeatedly herein.

