Brushless motor rotor, brushless motor, and method for forming brushless motor rotor

Abstract

A brushless motor rotor, a brushless motor and a method for forming a brushless motor rotor, wherein the brushless motor rotor comprises a rotor shaft, an intermediate ring and a rotor core arranged in sequence from the inside to the outside, the rotor core is fixed on the rotor shaft through the intermediate ring, and the brushless motor rotor also comprises balancing blocks connected to the rotor shaft and located at both axial ends of the rotor core. The intermediate ring and the balancing block are integrally injection molded to form an injection molded body, that is, the balancing block is injection molded by resin material to replace the copper block of the traditional design, thereby saving the cost of the copper block itself and the cost of the equipment, tooling and manpower for installing the copper block, and greatly reducing the overall cost of the brushless motor. At the same time, when there is a dynamic balancing error in the rotor and the balancing block needs to be cut and deweighted, only the resin material of the balancing block needs to be cut to ensure the balance of the brushless motor, thereby reducing the workload during the cutting and deweighting operation, thereby improving the production efficiency of the brushless motor.

Description

[Technical field]

[0001] The present invention relates to the technical field of motors, and in particular to a brushless motor rotor, a brushless motor and a forming method of a brushless motor rotor. [Background Technology]

[0002] As a small and efficient motor, brushless DC motors are increasingly being used in various fields and are deeply loved by major industries. At present, brushless motors include a stator and a rotor. The rotor includes a rotating shaft, a rotor core fixed on the rotating shaft, and two balancing blocks. The two balancing blocks are respectively arranged on both sides of the axial direction of the rotor core. During the molding of brushless motors, the dynamic balance error of the rotor will be caused due to assembly operation problems. In order to solve the dynamic balance error of the rotor, the balancing block needs to be cut and deweighted to ensure the balance of the brushless motor. However, since the balancing block is usually a copper block pressed on the rotating shaft, the workload of cutting and deweighting is large, resulting in low production efficiency. At the same time, the cost of the copper block itself, the cost of equipment, tooling and manpower for installing the copper block all require additional expenses, which greatly increases the overall cost of the brushless motor.

[0003] In view of this, it is indeed necessary to provide an improved brushless motor rotor, a brushless motor and a method for forming a brushless motor rotor to overcome the defects of the prior art. [Summary of the invention]

[0004] In view of the deficiencies in the prior art, an object of the present invention is to provide a brushless motor rotor, a brushless motor and a method for forming a brushless motor rotor with a simple structure and low cost.

[0005] The technical solution adopted by the present invention to solve the existing technical problems is: a brushless motor rotor, comprising a rotor shaft, an intermediate ring and a rotor core arranged in sequence from the inside to the outside, the rotor core is fixed to the rotor shaft through the intermediate ring, and the brushless motor rotor also includes a balancing block connected to the rotor shaft and located at both axial ends of the rotor core. The intermediate ring and the balancing block are integrally injection molded to form an injection molded body.

[0006] A further improved solution is: the injection molded body is integrally formed between the rotor shaft and the rotor core, and a positioning structure is provided between the injection molded body and the rotor shaft.

[0007] A further improvement is that the positioning structure includes a groove located on the surface of the rotor shaft, the groove includes a forward spiral groove and a reverse spiral groove extending along the axial direction, and the inner wall of the injection molded body extends into the forward spiral groove and the reverse spiral groove.

[0008] A further improvement is as follows: the rotor core is provided with a magnetic steel evenly fitted on the outer circle and a positioning ring sleeved on the outer side of the magnetic steel, and the positioning ring is two and respectively arranged at the axial ends of the rotor core.

[0009] A further improvement is that the lengths of the magnetic steel and the rotor core are equal, and the balancing block is connected to both axial ends of the rotor core.

[0010] The technical solution adopted by the present invention to solve the existing technical problems is: a brushless motor, including a motor stator and the above-mentioned brushless motor rotor, the motor stator surrounds the outer periphery of the rotor core of the brushless motor rotor, and the balancing block is exposed at both axial ends of the motor stator.

[0011] A further improved solution is: the motor stator includes a stator core and a winding wound on the stator core, the stator core includes a plurality of teeth extending radially inward and winding slots located between adjacent teeth, the winding is wound on the teeth and accommodated in the winding slots.

[0012] A further improved solution is: the ends of the teeth of the stator core are jointly arranged to form a receiving cavity, and the rotor core and the magnetic steel are located in the receiving cavity.

[0013] A further improvement is as follows: the brushless motor further comprises a fan blade mounted on the rotating shaft, the injection molded body further comprises a connecting portion between the rotor shaft and the fan blade, and the fan blade is fixed to the rotor shaft via the connecting portion.

[0014] The present invention can also adopt a technical solution to solve the problems of the prior art: a method for molding a brushless motor rotor, comprising the following steps: a. providing a rotor core and a lower mold, and installing and fixing the rotor core in the lower mold; b. providing a rotor shaft, and inserting the rotor shaft into the middle cavity of the rotor core; c. providing an upper mold, closing the upper mold and the lower mold with the rotor core and the rotor shaft located in the mold, so as to fix the rotor core and the rotor shaft at the same time; d. integrally injecting a plastic body into the mold, wherein the plastic body includes an intermediate ring located between the rotor shaft and the rotor core and balancing blocks located at both axial ends of the rotor core.

[0015] Compared with the prior art, the present invention has the following beneficial effects: the intermediate ring and the balancing block are integrally injection molded to form an injection molded body, that is, the balancing block is injection molded by resin material to replace the copper block of the traditional design, thereby saving the cost of the copper block itself and the cost of the equipment, tooling and manpower for installing the copper block, and greatly reducing the overall cost of the brushless motor. At the same time, when there is a dynamic balance error in the brushless motor rotor and the balancing block needs to be cut and deweighted, only the resin material of the balancing block needs to be cut to ensure the balance of the brushless motor, thereby reducing the workload during the cutting and deweighting operation, thereby improving the production efficiency of the brushless motor. [Drawings]

[0016] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings:

[0017] Figure 1 is a three-dimensional schematic diagram of a brushless motor of a preferred embodiment of the present invention;

[0018] Figure 2 yes Figure 1 A partially exploded view of a brushless motor is shown;

[0019] Figure 3 yes Figure 2 An exploded schematic diagram of a brushless motor rotor in the brushless motor shown;

[0020] Figure 4 yes Figure 1 The brushless motor shown is a cross-sectional view along the axial direction after the fan blades are removed;

[0021] Figure 5 yes Figure 1 A cross-sectional view of the brushless motor along the radial direction is shown.

[0022] Meaning of the reference numerals in the figures:

[0023] 100, brushless motor rotor 10, rotor shaft 11, groove 20, rotor core 21, magnetic steel 22, positioning ring 30, injection molding body 31, intermediate ring 32, balance block 33, connecting part 40, fan blade 50, motor stator 51, stator core 53, tooth part 54, winding groove 55, receiving chamber 200, brushless motor [Specific implementation method]

[0024] like Figure 1 to Figure 2 The brushless motor 100 of the present invention is shown, which is an 8-pole 6-slot motor with high efficiency and small size. The brushless motor 200 includes a motor stator 50 and a brushless motor rotor 100, the motor stator 50 surrounds the outer circumference of the brushless motor rotor 100, and the brushless motor rotor 100 rotates relative to the motor stator 50.

[0025] See also Figure 3 As shown, the brushless motor rotor 100 includes a rotor shaft 10, an intermediate ring 31 and a rotor core 20 arranged in sequence from the inside to the outside, and the rotor core 20 is fixed to the rotor shaft 10 through the intermediate ring 31. The brushless motor rotor 100 also includes a balancing block 32 connected to the rotor shaft 10 and located at both axial ends of the rotor core 20, and the intermediate ring 31 and the balancing block 32 are integrally injection-molded to form an injection molded body 30.

[0026] Combination Figure 5 As shown, the injection molding body 30 is integrally formed between the rotor shaft 10 and the rotor core 20, that is, the balancing block 32 is injection molded by a resin material to replace the copper block of the traditional design, thereby saving the cost of the copper block itself and the cost of the equipment, tooling and manpower for installing the copper block, and greatly reducing the overall cost of the brushless motor. At the same time, when there is a dynamic balance error in the brushless motor rotor 100 and the balancing block 32 needs to be cut to remove weight, only the resin material of the balancing block 32 needs to be cut to ensure the balance amount of the brushless motor 200, thereby reducing the workload during the cutting and removing weight operation, thereby improving the production efficiency of the brushless motor 200.

[0027] The rotor core 20 is provided with a magnetic steel 21 evenly attached to the outer circle and a positioning ring 22 sleeved on the outer side of the magnetic steel 21. The positioning rings 22 are two and are respectively arranged at the axial ends of the rotor core 20 to firmly connect the magnetic steel 21 to the rotor core 20. The lengths of the magnetic steel 21 and the rotor core 20 are equal, and the balancing block 32 is connected to the axial ends of the rotor core 20. The balancing block 32 is used to adjust the center of the rotor core 20 to coincide with the center of the rotor shaft 10.

[0028] A positioning structure is provided between the injection molded body 30 and the rotor shaft 10, and the positioning structure includes a groove 11 located on the surface of the rotor shaft 10. The groove 11 includes a forward spiral groove and a reverse spiral groove extending in the axial direction, and the inner wall of the injection molded body 30 extends into the forward spiral groove and the reverse spiral groove. The provision of the groove 11 allows the injection molded body 30 to be more securely connected and fixed to the rotor shaft 10, thereby preventing the injection molded body 30 from rotating relative to the rotor shaft 10 after long-term use.

[0029] The molding method of the brushless motor rotor 100 of the present invention comprises the following steps: a. providing a rotor core 20 and a lower mold, and installing and fixing the rotor core 20 in the lower mold; b. providing a rotor shaft 10, and inserting the rotor shaft 10 into the middle cavity of the rotor core 20; c. providing an upper mold, closing the upper mold and the lower mold with the rotor core 20 and the rotor shaft 10 located in the mold, so as to fix the rotor core 20 and the rotor shaft 10 at the same time; d. integrally injecting a plastic body 30 into the mold, wherein the plastic body 30 comprises an intermediate ring 31 located between the rotor shaft 10 and the rotor core 20 and balancing blocks 32 located at both axial ends of the rotor core 20.

[0030] See also Figures 4 to 5 As shown, the motor stator 50 surrounds the outer periphery of the rotor core 20 of the brushless motor rotor 100, and the balancing block 32 is exposed at both axial ends of the motor stator 50. The motor stator 50 includes a stator core 51 and a winding (not shown) wound on the stator core 51; the stator core 51 includes a plurality of teeth 53 extending radially inward and winding slots 54 located between adjacent teeth 53, and the winding is wound on the teeth 53 and received in the winding slots 54. The ends of the teeth 53 of the stator core 51 are collectively surrounded to form a receiving cavity 55, and the rotor core 20 and the magnet 21 are located in the receiving cavity 55.

[0031] In this embodiment, the brushless motor 200 further includes a fan blade 40 mounted on the rotating shaft 10, and the injection molded body 30 further includes a connecting portion 33 located between the rotor shaft 10 and the fan blade 40, and the fan blade 40 is fixed to the rotor shaft 10 through the connecting portion 33. When the brushless motor 200 is working, the rotor shaft 10 drives the fan blade 40 to rotate so that air flows, thereby achieving the effect of cooling and lowering the temperature, so that the brushless motor 200 works more stably.

[0032] In the present invention, the intermediate ring 31 and the balancing block 32 are integrally injection molded to form an injection molded body 30, that is, the balancing block 32 is injection molded by a resin material to replace the copper block of the traditional design, thereby saving the cost of the copper block itself and the cost of the equipment, tooling and manpower for installing the copper block, and greatly reducing the overall cost of the brushless motor 200. At the same time, when the brushless motor rotor 100 has a dynamic balance error and needs to perform a cutting and de-weighting operation on the balancing block 32, only the resin material of the balancing block 32 needs to be cut to ensure the balance amount of the brushless motor 200, thereby reducing the workload during the cutting and de-weighting operation, thereby improving the production efficiency of the brushless motor 200.

[0033] The present invention is not limited to the above specific embodiments. A person skilled in the art can easily understand that there are many alternatives to the brushless motor rotor and the forming method of the brushless motor of the present invention without departing from the principle and scope of the present invention. The protection scope of the present invention shall be subject to the content of the claims.

Claims

1. A brushless motor rotor, which is applied to a brushless motor, the brushless motor rotor comprising a rotor shaft, an intermediate ring and a rotor core arranged in sequence from the inside to the outside, the rotor core being fixed to the rotor shaft through the intermediate ring, the brushless motor rotor further comprising balancing blocks connected to the rotor shaft and located at both axial ends of the rotor core; characterized in that: The intermediate ring and the balancing weight are integrally injection-molded to form an injection-molded body; The injection molded body is integrally formed between the rotor shaft and the rotor core, and a positioning structure is provided between the injection molded body and the rotor shaft, the positioning structure comprises a groove located on the surface of the rotor shaft, the groove comprises a forward spiral groove and a reverse spiral groove extending in the axial direction, and the inner wall of the injection molded body extends into the forward spiral groove and the reverse spiral groove; The brushless motor includes a fan blade mounted to the rotor shaft, and the injection molded body also includes a connecting portion located between the rotor shaft and the fan blade, and the fan blade is fixed to the rotor shaft through the connecting portion; the diameter of the balancing block is larger than the diameter of the connecting portion, the connecting portion is connected to the end of the balancing block, and a step portion is formed at the connecting position between the connecting portion and the balancing block.

2. The brushless motor rotor according to claim 1, characterized in that: The rotor core is provided with magnetic steel evenly fitted on the outer circle and a positioning ring sleeved on the outer side of the magnetic steel. There are two positioning rings which are respectively arranged at the axial ends of the rotor core.

3. The brushless motor rotor according to claim 2, characterized in that: The magnetic steel and the rotor core have the same length, and the balancing block is connected to two axial ends of the rotor core.

4. A brushless motor, characterized in that: It comprises a motor stator and the brushless motor rotor according to any one of claims 1 to 3, wherein the motor stator surrounds the outer periphery of the rotor core of the brushless motor rotor, and the balancing block is exposed at both axial ends of the motor stator.

5. The brushless motor according to claim 4, characterized in that: The motor stator comprises a stator core and a winding wound on the stator core. The stator core comprises a plurality of teeth extending radially inward and winding slots between adjacent teeth. The winding is wound on the teeth and accommodated in the winding slots.

6. The brushless motor according to claim 5, characterized in that: The ends of the teeth of the stator core are jointly arranged to form a receiving cavity, and the rotor core and the magnetic steel are located in the receiving cavity.

7. A method for forming a brushless motor rotor, wherein the brushless motor rotor is the brushless motor rotor according to any one of claims 1 to 3, characterized in that: The following steps are involved: a. Providing a rotor core and a lower mold, and installing and fixing the rotor core to the lower mold; b. Providing a rotor shaft, inserting the rotor shaft into the middle cavity of the rotor core; c. providing an upper mold, closing the upper mold and the lower mold with the rotor core and the rotor shaft located in the mold to fix the rotor core and the rotor shaft at the same time; d. Injection molding an injection molded body into a mold, wherein the injection molded body includes an intermediate ring located between the rotor shaft and the rotor core and balancing blocks located at both axial ends of the rotor core; A positioning structure is provided between the injection molding body and the rotor shaft, the positioning structure comprises a groove located on the surface of the rotor shaft, the groove comprises a forward spiral groove and a reverse spiral groove extending in the axial direction, and the inner wall of the injection molding body extends into the forward spiral groove and the reverse spiral groove; The brushless motor includes a fan blade mounted to the rotor shaft, and the injection molded body also includes a connecting portion located between the rotor shaft and the fan blade, and the fan blade is fixed to the rotor shaft through the connecting portion; the diameter of the balancing block is larger than the diameter of the connecting portion, the connecting portion is connected to the end of the balancing block, and a step portion is formed at the connecting position between the connecting portion and the balancing block.

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