A new type of direct current brushless motor

Abstract

The utility model discloses a new -type direct current brushless motor, it includes casing, front end cover, rear end cover, the inside of casing is equipped with stator subassembly, rotor subassembly, and stator subassembly clamps solid between front and rear end cover, and rotor subassembly includes metal core shaft, plastic pivot, magnetic ring, the front bearing is inlaid in the front bearing hole of front end cover, and the rear bearing is inlaid in the rear bearing hole of rear end cover, and front end cover, rear end cover are hard rubber spare respectively, and front bearing, rear bearing are oil -containing bearing respectively, and front bearing rivets in the front bearing hole of front end cover, and rear bearing rivets in the rear bearing hole of rear end cover, and the plastic pivot is equipped with elastic part between front end cover, and elastic part is towards the back elastic resistance and stop plastic pivot, and the rear bearing hole of rear end cover is blind hole structure, and the bottom of rear bearing hole is equipped with end face spacer, and the rear end of metal core shaft and end face spacer abut. The utility model can effectively eliminate the rotor axial play and improve the stability when the motor works, that is, has the advantages of novel structure design, good stability.

Description

Technical Field

[0001] This utility model relates to the field of DC brushless motor technology, and in particular to a novel DC brushless motor. Background Technology

[0002] The Chinese utility model patent with patent number ZL202122080807.9 and patent name, entitled "Brushless DC Motor," specifically discloses the following technical solution: A brushless DC motor, comprising: a metal housing and a stator and a rotor core located within the metal housing, the rotor core being located within the stator; a metal front cover and a metal rear cover being respectively installed on the front and rear faces of the metal housing; the rotor core being fixed to the outer surface of a rotor shaft; the two ends of the rotor shaft being connected to the metal front cover and the metal rear cover respectively via a front bearing and a rear bearing; an external thread on the side surface of the metal front cover being rotatably connected to an internal thread on the inner surface of the metal housing; at least three rivet points are provided circumferentially on the end face of the metal housing near the metal rear cover, and the metal housing is connected to the metal rear cover via at least three rivet points; the housing is an aluminum housing, and both the metal front cover and the metal rear cover are aluminum covers.

[0003] It should be noted that the above-mentioned brushless DC motor still has the following defects: the front end of the rotor shaft is connected to the metal front cover through the front bearing, and the rear end of the rotor shaft is connected to the metal rear cover through the rear bearing. Due to the objective assembly gap at the positions of the front and rear bearings, the brushless DC motor has the problem of axial movement. The axial movement of the rotor will cause the brushless DC motor to vibrate and make noise during operation, and will also cause the rotor to deviate from the initial axial position, thus affecting the stability of the motor operation. Utility Model Content

[0004] The purpose of this invention is to provide a novel brushless DC motor that addresses the shortcomings of existing technologies. This novel brushless DC motor has a novel structural design and can effectively eliminate rotor axial movement and improve the stability of the motor during operation.

[0005] To achieve the above objectives, this utility model is implemented through the following technical solution.

[0006] A novel brushless DC motor includes a housing, a front cover riveted to the front end of the housing, and a rear cover riveted to the rear end of the housing. The housing contains a stator assembly and a rotor assembly located inside the stator assembly. The stator assembly is secured between the front cover and the rear cover. The rotor assembly includes a metal spindle. The front cover has a front bearing hole, in which a front bearing is fitted and mounted on the outer periphery of the front end of the metal mandrel. The front bearing hole is a through hole structure, and the front end of the metal mandrel passes through the front bearing hole of the front cover. The rear cover has a rear bearing hole, in which a rear bearing is fitted and mounted on the outer periphery of the rear end of the metal mandrel. The front cover and the rear cover are both made of hard rubber parts, and the front bearing and the rear bearing are both oil-impregnated bearings. The front bearing is riveted into the front bearing hole of the front cover, and the rear bearing is riveted into the rear bearing hole of the rear cover. The center hole of the front bearing is clearance-fitted with the front end of the metal spindle, and the center hole of the rear bearing is clearance-fitted with the rear end of the metal spindle. The rotor assembly also includes a plastic shaft that is riveted and fitted around the metal spindle, and a magnetic ring is riveted and fitted around the plastic shaft. An elastic element is installed between the plastic shaft and the front cover, which is fitted around the metal spindle. The elastic element elastically pushes against the plastic shaft from the rear. The rear bearing hole of the rear end cover is a blind hole structure, and an end face gasket is installed at the bottom of the rear bearing hole. The rear end face of the metal mandrel abuts against the end face gasket.

[0007] The elastic element includes a front gasket, an elastic silicone pad, and a rear gasket stacked sequentially from front to back. The front gasket, the elastic silicone pad, and the rear gasket are respectively fitted around the metal mandrel. The front surface of the front gasket abuts against the rear end face of the front bearing, and the rear surface of the rear gasket abuts against the plastic shaft.

[0008] The elastic element is a compression spring, with its front end abutting against the front end cover and its rear end abutting against the plastic shaft.

[0009] The front end of the plastic shaft is provided with a spring positioning part that surrounds the metal core shaft and protrudes forward, and the rear end of the compression spring is fitted around the spring positioning part.

[0010] The metal mandrel is knurled at the rivet fitting position of the plastic shaft.

[0011] The inner circumferential surface of the magnetic ring is provided with a number of grooves arranged in a ring array and extending along the axis of the magnetic ring. The plastic shaft is provided with a boss corresponding to each groove of the magnetic ring, and each boss is embedded into the corresponding groove. The plastic shaft is also provided with several tight-fitting ribs arranged in a ring array. The tight-fitting ribs are located on the side of the boss, and each tight-fitting rib presses against the inner circumferential surface of the contact magnetic ring. There is a gap between the magnetic ring and the plastic shaft, and the gap is filled with colloid.

[0012] Compared with existing technologies, this invention has the following advantages: Specifically, the elastic force of the elastic element causes the rear end face of the metal spindle to press against the contact end face gasket, and the elastic element keeps the rotor assembly in its initial axial position. Even if the rotor assembly experiences axial runout due to external forces during rotation, the elastic element will cause the rotor assembly to return to its initial axial position after the runout ends, thereby eliminating axial movement of the rotor. Therefore, the novel brushless DC motor of this invention has the advantages of novel structural design and good stability. Attached Figure Description

[0013] The present invention will be further described below with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention.

[0014] Figure 1 This is a schematic diagram of the structure of this utility model.

[0015] Figure 2 This is a cross-sectional schematic diagram of the present invention.

[0016] Figure 3 This is a cross-sectional schematic diagram of another embodiment of the present invention.

[0017] Figure 4 This is a schematic diagram of the structure of the metal mandrel of this utility model.

[0018] Figure 5 This is a cross-sectional schematic diagram of the rotor assembly of this utility model.

[0019] exist Figures 1 to 5 This includes: 1-Housing; 2-Front end cover; 21-Front bearing hole; 3-Rear end cover; 31-Rear bearing hole; 4-Stator assembly; 5-Rotor assembly; 51-Metal spindle; 511-Knurled; 52-Plastic shaft; 521-Spring positioning part; 522-Boss; 523-Fitting rib; 53-Magnetic ring; 531-Groove; 54-Glue gap; 61-Front bearing; 62-Rear bearing; 7-End face gasket; 81-Front gasket; 82-Elastic silicone gasket; 83-Rear gasket; 84-Compression spring. Detailed Implementation

[0020] The present invention will now be described in conjunction with specific embodiments.

[0021] Example 1, as Figures 1 to 3As shown, a novel brushless DC motor includes a housing 1, a front cover 2 riveted to the front end of the housing 1, and a rear cover 3 riveted to the rear end of the housing 1. A stator assembly 4 and a rotor assembly 5 located inside the stator assembly 4 are installed inside the housing 1. The stator assembly 4 is secured between the front cover 2 and the rear cover 3. The rotor assembly 5 includes a metal spindle 51. The stator assembly 41 in this embodiment is already prior art and will not be described in detail here.

[0022] Among them, such as Figure 2 and Figure 3 As shown, the front cover 2 has a front bearing hole 21, in which a front bearing 61 is fitted and mounted on the periphery of the front end of the metal spindle 51. The front bearing hole 21 is a through hole structure, and the front end of the metal spindle 51 passes through the front bearing hole 21 of the front cover 2. The rear cover 3 has a rear bearing hole 31, in which a rear bearing 62 is fitted and mounted on the periphery of the rear end of the metal spindle 51.

[0023] Furthermore, such as Figure 2 and Figure 3 As shown, the front cover 2 and the rear cover 3 are both made of rigid rubber. The front bearing 61 and the rear bearing 62 are both oil-impregnated bearings. The front bearing 61 is riveted into the front bearing hole 21 of the front cover 2, and the rear bearing 62 is riveted into the rear bearing hole 31 of the rear cover 3. The center hole of the front bearing 61 is clearance-fitted with the front end of the metal mandrel 51, and the center hole of the rear bearing 62 is clearance-fitted with the rear end of the metal mandrel 51. It should be noted that the front cover 2 and the rear cover 3 in this embodiment can be injection molded from high-strength, high-temperature resistant nylon or other engineering plastics.

[0024] Furthermore, such as Figure 2 , Figure 3 as well as Figure 5 As shown, the rotor assembly 5 also includes a plastic shaft 52 riveted and fitted around the metal spindle 51, and a magnetic ring 53 riveted and fitted around the plastic shaft 52. It should be noted that, for the magnetic ring 53 in this embodiment, it can be a neodymium iron boron sintered part.

[0025] In addition, such as Figure 2 and Figure 3 As shown, an elastic element is installed between the plastic shaft 52 and the front cover 2, which is fitted around the metal spindle 51. The elastic element elastically abuts against the plastic shaft 52 from the rear.

[0026] And also, such as Figure 2 and Figure 3 As shown, the rear bearing hole 31 of the rear end cover 3 is a blind hole structure, and an end face gasket 7 is installed at the bottom of the rear bearing hole 31. The rear end face of the metal spindle 51 abuts against the end face gasket 7.

[0027] It should be noted that, since the front cover 2 and the rear cover 3 are both made of plastic, when the front bearing 61 and the rear bearing 62 are riveted and installed in the corresponding front bearing hole 21 and rear bearing hole 31, the front cover 2 and the rear cover 3 will undergo plastic deformation, so that the front bearing 61 and the rear bearing 62 are fixedly installed in the corresponding front bearing hole 21 and rear bearing hole 31, and can effectively ensure the axial position of the front bearing 61 and the front cover 2 and the axial position of the rear bearing 62 and the rear cover 3.

[0028] It should be emphasized that, for the elastic element in this embodiment, because it elastically abuts against the plastic shaft 52 of the rotor assembly 5, the elastic force of the elastic element causes the rear end face of the metal spindle 51 to press against the end face gasket 7 inside the rear bearing hole 31. When the motor is assembled, the elastic element is in a compressed state, and the elastic force of the elastic element causes the rear end face of the metal spindle 51 to press against the end face gasket 7. The elastic element keeps the rotor assembly 5 in its initial axial position. Even if the rotor assembly 5 experiences axial runout due to external force during rotation, the elastic element will cause the rotor assembly 5 to return to its initial axial position after the runout ends, thereby eliminating the axial movement of the rotor. When there is no axial movement or play in the motor, the motor has higher precision, less wobbling and vibration, less noise, less shaking, and higher stability.

[0029] In summary, through the above structural design, the novel brushless DC motor of this embodiment can effectively eliminate rotor axial displacement and improve the stability of the motor during operation. That is, the novel brushless DC motor of this embodiment has the advantages of novel structural design and good stability.

[0030] Example 2, as Figure 2 As shown, the difference between this embodiment 2 and embodiment 1 is that the elastic element includes a front gasket 81, an elastic silicone pad 82, and a rear gasket 83 stacked sequentially from front to back. The front gasket 81, the elastic silicone pad 82, and the rear gasket 83 are respectively fitted around the metal spindle 51. The front surface of the front gasket 81 abuts against the rear end face of the front bearing 61, and the rear surface of the rear gasket 83 abuts against the plastic rotating shaft 52.

[0031] For the elastic element in this second embodiment, the elastic silicone pad 82 is used to provide the elastic force that causes the rotor assembly 5 to return to the initial axial position, the front pad 81 is used to separate the elastic silicone pad 82 from the front end cover 2, and the rear pad 83 is used to separate the elastic silicone pad 82 from the plastic shaft 52.

[0032] Example 3, as Figure 3 As shown, the difference between this embodiment three and embodiment one is that the elastic element is a compression spring 84, the front end of the compression spring 84 abuts against the front end cover 2, and the rear end of the compression spring 84 abuts against the plastic rotating shaft 52.

[0033] An auxiliary shim is installed between the compression spring 84 and the plastic shaft 52 to separate the compression spring 84 and the plastic shaft 52.

[0034] For the elastic element in this embodiment three, the compression spring 84 is used to provide the elastic force that causes the rotor assembly 5 to return to its initial axial position.

[0035] Example 4, as Figure 3 As shown, the difference between this embodiment four and embodiment three is that: the front end of the plastic shaft 52 is provided with a spring positioning part 521 that surrounds the metal core shaft 51 and protrudes forward, and the rear end of the compression spring 84 is fitted around the spring positioning part 521.

[0036] The spring positioning part 521 in this embodiment can effectively position the compression spring 84 to ensure that the compression spring 84 is stable in position during use.

[0037] Example 5, as Figure 4 As shown, the difference between this fifth embodiment and the first embodiment is that the metal mandrel 51 is provided with knurling 511 at the rivet fitting position of the plastic rotating shaft 52.

[0038] It should be explained that the metal mandrel 51 is knurled 511, and the plastic shaft 52 is riveted to the metal mandrel 51. The knurling 511 can effectively ensure the riveting strength between the plastic shaft 52 and the metal mandrel 51, and can effectively prevent relative movement between the two.

[0039] Example 6, as Figure 5 As shown, the difference between this sixth embodiment and the first embodiment is that: the inner circumferential surface of the magnetic ring 53 is provided with a plurality of grooves 531 arranged in a ring array and extending along the axis of the magnetic ring 53 respectively; the plastic rotating shaft 52 is provided with a boss 522 corresponding to each groove 531 of the magnetic ring 53, and each boss 522 is embedded into the corresponding groove 531.

[0040] The plastic shaft 52 is also provided with a number of tight-fitting ribs 523 arranged in a ring array. The tight-fitting ribs 523 are located on the side of the boss 522, and each tight-fitting rib 523 presses against the inner circumferential surface of the contact magnetic ring 53.

[0041] In addition, there is a glue-filled gap 54 between the magnetic ring 53 and the plastic shaft 52, and the glue-filled gap 54 is filled with glue (not shown in the figure).

[0042] It should be explained that, by cooperating with the groove 531 of the magnetic ring 53 and the boss 522 of the plastic shaft 52, this embodiment six can effectively prevent relative rotation between the magnetic ring 53 and the plastic shaft 52.

[0043] Furthermore, by using the adhesive within the adhesive gap 54 to achieve an adhesive connection between the magnetic ring 53 and the plastic shaft 52, this sixth embodiment can further improve the stability and reliability of the magnetic ring 53 installation.

[0044] The above description is only a preferred embodiment of this utility model. For those skilled in the art, there will be changes in the specific implementation method and application scope based on the idea of ​​this utility model. The content of this specification should not be construed as a limitation of this utility model.

Claims

1. A novel brushless DC motor, comprising a housing (1), a front cover (2) riveted to the front end of the housing (1), and a rear cover (3) riveted to the rear end of the housing (1), wherein a stator assembly (4) and a rotor assembly (5) located inside the stator assembly (4) are installed inside the housing (1), the stator assembly (4) is secured between the front cover (2) and the rear cover (3), and the rotor assembly (5) includes a metal spindle (51); The front cover (2) has a front bearing hole (21), in which a front bearing (61) is fitted and mounted on the periphery of the front end of the metal spindle (51). The front bearing hole (21) is a through hole structure, and the front end of the metal spindle (51) passes through the front bearing hole (21) of the front cover (2). The rear cover (3) has a rear bearing hole (31), in which a rear bearing (62) is fitted and mounted on the periphery of the rear end of the metal spindle (51). Its features are: The front cover (2) and the rear cover (3) are hard rubber parts, the front bearing (61) and the rear bearing (62) are oil-impregnated bearings, the front bearing (61) is riveted in the front bearing hole (21) of the front cover (2), and the rear bearing (62) is riveted in the rear bearing hole (31) of the rear cover (3). The center hole of the front bearing (61) is clearance-fitted with the front end of the metal spindle (51), and the center hole of the rear bearing (62) is clearance-fitted with the rear end of the metal spindle (51). The rotor assembly (5) also includes a plastic shaft (52) that is riveted and fitted around the metal spindle (51), and a magnetic ring (53) is riveted and fitted around the plastic shaft (52). An elastic element is installed between the plastic shaft (52) and the front cover (2), which is fitted around the metal spindle (51). The elastic element elastically pushes against the plastic shaft (52) from the rear. The rear bearing hole (31) of the rear end cover (3) is a blind hole structure. The bottom of the rear bearing hole (31) is equipped with an end face gasket (7), and the rear end face of the metal spindle (51) abuts against the end face gasket (7).

2. The novel brushless DC motor according to claim 1, characterized in that: The elastic element includes a front gasket (81), an elastic silicone pad (82), and a rear gasket (83) stacked sequentially from front to back. The front gasket (81), the elastic silicone pad (82), and the rear gasket (83) are respectively fitted around the metal spindle (51). The front surface of the front gasket (81) abuts against the rear end face of the front bearing (61), and the rear surface of the rear gasket (83) abuts against the plastic shaft (52).

3. A novel brushless DC motor according to claim 1, characterized in that: The elastic element is a compression spring (84). The front end of the compression spring (84) abuts against the front end cover (2), and the rear end of the compression spring (84) abuts against the plastic shaft (52).

4. A novel brushless DC motor according to claim 3, characterized in that: The front end of the plastic shaft (52) is provided with a spring positioning part (521) that surrounds the metal core shaft (51) and protrudes forward, and the rear end of the compression spring (84) is fitted around the spring positioning part (521).

5. A novel brushless DC motor according to claim 1, characterized in that: The metal mandrel (51) is provided with knurling (511) at the rivet fitting position of the plastic shaft (52).

6. A novel brushless DC motor according to claim 1, characterized in that: The inner circumferential surface of the magnetic ring (53) is provided with a plurality of grooves (531) arranged in a ring array and extending along the axis of the magnetic ring (53). The plastic shaft (52) is provided with a boss (522) corresponding to each groove (531) of the magnetic ring (53), and each boss (522) is embedded into the corresponding groove (531). The plastic shaft (52) is also provided with a number of tight-fitting ribs (523) arranged in a ring array. The tight-fitting ribs (523) are located on the side of the boss (522), and each tight-fitting rib (523) presses against the inner circumferential surface of the contact magnetic ring (53). There is a glue-filled gap (54) between the magnetic ring (53) and the plastic shaft (52), and the glue-filled gap (54) is filled with glue.

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