Novel outer rotor direct current brushless motor

Abstract

The utility model discloses a novel outer rotor direct current brushless motor, which comprises a shaft sleeve, an inner stator sleeved on the shaft sleeve, a motor driving plate sleeved above the inner stator, a bearing installed in the shaft sleeve, a rotating shaft arranged in the center of the bearing, an outer rotor rotatably arranged outside the inner stator, and the outer rotor and the bottom end of the rotating shaft are connected and rotate synchronously. And an anti-vibration positioning piece capable of quickly fixing the bearing in the shaft sleeve is inserted between the bearing and the inner wall of the shaft sleeve. The utility model aims to provide the bearing which adopts two bearings with the same size to bear radial and axial loads together, so that the service life of the bearings is prolonged, the problem of eccentricity is reduced, the maintenance time and complexity of the bearings are reduced, and a C-shaped anti-vibration positioning piece is inserted between the bearings and the inner wall of the shaft sleeve, so that the service life of the bearing is prolonged. The bearing is rapidly fixed through interference fit with the elastic ring on the inner wall of the bearing groove, the loosening phenomenon of the bearing in the working process can be effectively reduced, and therefore vibration and noise are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of brushless motors, in particular to a novel outer rotor DC brushless motor. Background Art

[0002] The outer rotor brushless DC motor is a unique brushless motor with the stator located in the center of the motor and the rotor wrapped around the stator. This design has significant advantages over traditional inner rotor motors, including higher torque density and better heat dissipation, and is therefore widely used in drones, electric bicycles, model aircraft, fans and other fields.

[0003] Although outer rotor brushless DC motors excel in performance and efficiency, shaft vibration and noise are still common problems in actual use. These problems are particularly concentrated in the bearing position. Bearings play a key role in supporting the shaft and reducing friction in motors. The bearings of traditional outer rotor brushless DC motors usually adopt a large and small bearing configuration. The large bearing is installed at the front end of the motor (close to the load end) to withstand large radial and axial loads. The small bearing is installed at the rear end of the motor (away from the load end) and is mainly used for positioning and auxiliary support. However, the large and small bearing configuration is prone to uneven load distribution in actual use, resulting in accelerated wear of the large bearing and potential eccentricity problems, causing vibration and resonance to occur and generate noise. In addition, during assembly, the bearings are usually pressed into the bearing slot using a press to fix them. This method can ensure the stability and reliability of the bearing during motor operation. However, this also brings maintenance difficulties.

[0004] In order to solve the vibration and resonance, some manufacturers wrap a bearing sleeve around the bearing and then install it in the motor's mounting groove. The shaft of the outer rotor passes through the bearing sleeve and the bearing and fits with the bearing. The vibration caused by the unconstrained movement of loose rolling elements is reduced by the matching of the bearing sleeve, thereby reducing the vibration and noise of the motor. Although the bearing sleeve in this solution can reduce a certain amount of noise, the bearing still needs to be pressed into the mounting groove with a press machine to fix the bearing and the bearing sleeve at the same time.

[0005] Bearings are consumable parts. After working for a long time, wear is inevitable. The worn bearings will cause vibration and noise of the shaft, further affecting the normal operation of the motor. Since the bearings are tightly pressed into the installation slots without any gap, it will be very difficult to repair or replace the bearings in the future. Ordinary people cannot replace and repair the press-fitted bearings, which increases the complexity and cost of maintaining the motor.

[0006] Therefore, the existing outer rotor brushless DC motor needs to be further optimized and improved. Utility Model Content

[0007] The utility model aims to provide a novel outer rotor DC brushless motor which adopts two bearings of the same size, is easier to disassemble and replace, and can reduce a certain amount of noise.

[0008] In order to achieve the above-mentioned purpose, the utility model adopts the following scheme: a new type of outer rotor DC brushless motor, including a sleeve with a through-shaped upper and lower part, an inner stator is sleeved on the outer circumferential wall of the sleeve, a motor drive plate is sleeved on the outer circumferential wall of the sleeve located above the inner stator, a bearing is embedded in the sleeve, a rotating shaft is rotatably passed through the center of the bearing, the top end of the rotating shaft extends out of the top opening of the sleeve, and the bottom end of the rotating shaft extends out of the bottom opening of the sleeve, an outer rotor is rotatably arranged outside the inner stator, the outer rotor is connected to the bottom end of the rotating shaft and rotates synchronously, and an anti-seismic positioning piece that can quickly fix the bearing in the sleeve is inserted between the bearing and the inner wall of the sleeve. The anti-seismic positioning piece is inserted between the bearing and the inner wall of the sleeve, and the bearing is quickly fixed by interference fit. The design of the anti-seismic positioning piece can effectively reduce the loosening phenomenon of the bearing during operation, thereby reducing vibration and noise. This quick fixing method also facilitates the disassembly and replacement of the bearing, and improves the convenience of maintenance. At the same time, it can also avoid the use of a press machine during the assembly process to apply high pressure, which may cause damage to the bearing and shorten its service life.

[0009] As a preferred solution of the utility model, drive plate fixing ears are provided at intervals on the circumferential outer wall of the sleeve located above the motor drive plate, the motor drive plate is detachably mounted on the sleeve by screws inserted into the drive plate fixing ears, and motor fixing ears are provided at intervals on the circumferential outer wall of the sleeve near the top.

[0010] As a preferred solution of the utility model, the inner stator includes an iron core fixedly sleeved on the circumferential outer wall of the shaft sleeve and a winding wound in the iron core slot.

[0011] As a preferred embodiment of the utility model, the outer rotor includes an annular shell surrounding the outer circumference of the iron core, the bottom end of the annular shell is provided with a bottom plate capable of closing the bottom end of the annular shell, a plug hole is passed through the center of the bottom plate, the bottom end of the rotating shaft is inserted into the plug hole, and an annular magnet is provided along the circumferential inner wall of the annular shell.

[0012] As a preferred solution of the utility model, bearing grooves are respectively provided in the openings at the top and bottom ends of the sleeve, the diameters of the two bearing grooves are the same and larger than the diameter of the inner wall of the sleeve circumference, and the bearings are respectively installed in the bearing grooves. The bearings are installed in the bearing grooves. The design of the bearing grooves makes the bearing installation more stable, helps to reduce the shaking and vibration of the bearings, and the use of two bearings of the same size makes the load distribution more uniform. The two bearings of the same size bear radial and axial loads together, which can extend the service life of the bearings, reduce the eccentricity problem and further reduce the noise.

[0013] As a further solution of the utility model, the anti-vibration positioning member includes an anti-vibration ring that is interference-fitted between the circumferential outer wall of the bearing and the inner wall of the bearing groove in which it is located. The anti-vibration ring is in the shape of a "C", and the height of the anti-vibration ring is greater than the thickness of the bearing. A protruding abutment is provided on the circumferential inner wall of the anti-vibration ring that is higher than the bearing. The abutment extends inwardly along the outer edge of the anti-vibration ring to one side of the bearing and abuts against the corresponding outer peripheral edge of the bearing. An elastic clamp that can clamp the two free ends of the anti-vibration ring and prevent it from falling off from the bearing groove is provided on the inner wall of the bearing groove between the two free ends of the anti-vibration ring. The anti-vibration ring is in the shape of a "C", and its height is greater than the thickness of the bearing. The abutment extends inwardly along the outer edge of the anti-vibration ring to one side of the bearing and abuts against the outer peripheral edge of the bearing. This design can effectively fix the bearing and reduce vibration caused by looseness.

[0014] As a further solution of the utility model, the elastic clamp includes a clamping groove arranged on the inner wall of the bearing groove at an interval of up and down, an annular elastic ring is embedded between the clamping grooves, and the left and right sides of the elastic ring are respectively provided with convex points protruding to both sides, and the two free ends of the anti-vibration ring are respectively provided with notches that can be matched with the corresponding convex points and clamped together. The matching design of the elastic ring prevents the anti-vibration ring from falling off, thereby improving the reliability of the bearing fixation.

[0015] As a preferred solution of the utility model, oblique chamfers are provided at the corners of the two free ends of the anti-vibration ring away from the opening of the bearing groove.

[0016] As a preferred embodiment of the utility model, at least one inwardly recessed positioning groove is provided on the inner wall of the bearing groove, one end of the positioning groove extends through the opening of the bearing groove, and a convex strip that can be inserted into the positioning groove is provided on the circumferential outer wall of the anti-vibration ring, thereby increasing the fixing stability of the anti-vibration ring and further reducing the vibration and noise of the bearing.

[0017] As a preferred solution of the utility model, a clamping tube extending downward is provided along the circumference of the insertion hole, and the bottom end of the rotating shaft passes through the insertion hole and is inserted into the clamping tube through interference fit. This design ensures a reliable connection between the rotating shaft and the outer rotor, and reduces noise and vibration caused by loose rotating shaft.

[0018] In summary, the utility model has the following beneficial effects compared to the prior art: the utility model adopts two bearings of the same size to distribute the load more evenly than a large and a small bearing configuration. Two bearings of the same size can jointly bear radial and axial loads, thereby extending the service life of the bearing and reducing the eccentricity problem. Secondly, maintenance and replacement become simpler, because the same tools and steps can be used for bearings of the same size, reducing maintenance time and complexity. At the same time, bearings of uniform size can simplify the motor structure design and reduce the overall weight, which is especially beneficial in applications with limited space. Vibration and noise are also effectively controlled, and the uniform load distribution reduces unbalanced forces and resonance, and improves running stability and quietness. The use of bearings of the same size not only simplifies the difficulty of production, procurement and inventory management, but also reduces the overall cost of the motor and improves economic benefits.

[0019] Importantly, the structural design of the anti-vibration positioning piece and the design of the positioning groove and convex strips jointly improve the running stability and service life of the motor. The anti-vibration positioning piece formed by the "C"-shaped anti-vibration ring is inserted between the outer wall of the bearing circumference and the inner wall of the bearing groove, and the height of the anti-vibration ring is greater than the thickness of the bearing it wraps and clamps, and a protruding stop is provided on the raised part, which can effectively fix the bearing and reduce the vibration caused by loosening. At the same time, the design of the elastic ring ensures that the anti-vibration ring cannot fall off, further enhancing the fixing stability of the bearing. The positioning groove provided on the inner wall of the bearing groove cooperates with the convex strip on the outer wall of the anti-vibration ring, making the installation of the anti-vibration ring more stable. This design not only enhances the bonding force between the anti-vibration ring and the bearing groove, but also makes the disassembly and maintenance of the bearing more convenient and efficient. The design of fixing the bearing with the anti-vibration ring not only reduces the vibration and noise problems caused by looseness, but also facilitates the disassembly and maintenance of the bearing. When disassembling, you only need to pull out the anti-vibration ring to easily disassemble the bearing. Through the structural optimization of the utility model, the performance and user experience of the outer rotor DC brushless motor in terms of vibration resistance, noise reduction and convenient maintenance are greatly improved, making the maintenance of the motor easier. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional view of the utility model.

[0021] Figure 2 for Figure 1 Magnified view at A in the middle.

[0022] Figure 3 A cross-sectional view of the present invention.

[0023] Figure 4 for Figure 3 Magnified view at B.

[0024] Figure 5 This is one of the exploded views of the present utility model.

[0025] Figure 6 This is the second exploded view of the present utility model.

[0026] Figure 7 for Figure 6 Magnified view at center C.

[0027] Figure 8 This is one of the schematic diagrams of the state in which the anti-vibration ring is clamped onto the elastic ring in the utility model.

[0028] Fig. 9 This is the second schematic diagram of the state in which the anti-vibration ring is clamped onto the elastic ring in the present invention.

[0029] Fig.10 It is a schematic diagram of the state in which the anti-vibration ring of the utility model has been clamped on the elastic ring.

[0030] Explanation of the reference numerals in the accompanying drawings: 1. sleeve; 2. inner stator; 3. bearing; 4. rotating shaft; 5. motor drive plate; 6. outer rotor; 7. anti-vibration positioning piece; 8. elastic clamp; 10. drive plate fixing ear; 11. bearing groove; 12. motor fixing ear; 13. positioning groove; 21. iron core; 22. winding; 61. annular shell; 62. bottom plate; 63. jack; 64. annular magnet; 65. clamping tube; 71. anti-vibration ring; 72. stopper; 73. inner groove; 81. clamping groove; 82. elastic ring; 83. convex point; 84. missing groove; 711. chamfer; 712. convex strip. DETAILED DESCRIPTION

[0031] The following specific implementation contents provide a variety of different embodiments or examples for implementing the utility model. Of course, these are only embodiments or examples and are not intended to be limiting. In addition, repeated reference numerals may be used in different embodiments, such as repeated numbers and / or letters. These repetitions are for the purpose of simply and clearly describing the present invention and do not represent a specific relationship between the different embodiments and / or structures discussed.

[0032] In addition, spatially related words may be used, such as "below", "lower side", "from the inside out", "above", "upper side" and similar words. These relative words are for the convenience of describing the relationship between one element or feature and another element or feature in the drawings. These spatially related words include different orientations of the device in use or operation, as well as the orientations described in the drawings. The device may be turned to different orientations, rotated 90 degrees or other orientations, and the spatially related adjectives used therein may also be interpreted in the same way. Therefore, it cannot be understood as a limitation of the present invention. The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods: Figures 1 to 10 A novel outer rotor DC brushless motor shown in the figure includes a shaft sleeve 1 which is through-shaped from top to bottom, an inner stator 2 consisting of an iron core 21 and a winding 22 wound in a groove of the iron core 21 is fixedly sleeved on the circumferential outer wall of the shaft sleeve 1, a motor drive plate 5 is sleeved on the circumferential outer wall of the shaft sleeve 1 located above the inner stator 2, drive plate fixing ears 10 are spaced apart on the circumferential outer wall of the shaft sleeve 1 located above the motor drive plate 5, the motor drive plate 5 is detachably mounted on the shaft sleeve 1 by screws inserted into the drive plate fixing ears 10, and motor fixing ears 12 are spaced apart on the circumferential outer wall of the shaft sleeve 1 near the top. A bearing groove 11 is respectively provided in the openings at the top and bottom ends of the sleeve 1. The diameters of the two bearing grooves 11 are the same and larger than the diameter of the inner wall of the circumference of the sleeve 1. Bearings 3 of the same size are respectively installed in the two bearing grooves 11. An annular gap is provided between the outer wall of the bearing 3 and the inner wall of the bearing groove 11. A rotating shaft 4 is rotatably passed through the center of the bearing 3. The top end of the rotating shaft 4 extends out of the top opening of the sleeve 1, and the bottom end of the rotating shaft 4 extends out of the bottom opening of the sleeve 1. An outer rotor 6 consisting of an annular shell 61 surrounding the circumference of the iron core 21, an annular magnet 64 provided along the circumferential inner wall of the annular shell 61, and a bottom plate 62 capable of closing the bottom end of the annular shell 61 is rotatably provided outside the inner stator 2. An insertion hole 63 is passed through the center of the bottom plate 62. A clamping tube 65 extending downward is provided along the circumference of the insertion hole 63. After the bottom end of the rotating shaft 4 passes through the insertion hole 63, it is inserted into the clamping tube 65 through interference fit and rotates synchronously with the outer rotor 6. An anti-vibration positioning member 7 is inserted into the gap between the circumferential outer wall of the bearing 3 and the inner wall of the bearing groove 11 where the bearing 3 is located, and can quickly fix the bearing 3 in the bearing groove 11 .

[0034] The anti-vibration positioning member 7 includes an anti-vibration ring 71 which is inserted between the outer circumferential wall of the bearing 3 and the inner wall of the bearing groove 11 with interference fit. The anti-vibration ring 71 is in a "C" shape and is made of hard plastic to reduce the noise and vibration caused by the bearing 3. The height of the anti-vibration ring 71 is greater than the thickness of the bearing 3. Bevel chamfers 711 are provided at the corners of the two free ends of the anti-vibration ring 71 away from the opening of the bearing groove 11. A protruding abutment 72 is provided on the inner circumferential wall of the anti-vibration ring 71 that is higher than the bearing 3. The abutment 72 extends inwardly along the outer edge of the anti-vibration ring 71 to one side of the bearing 3 and abuts against the corresponding outer circumferential edge of the bearing 3. A plurality of inner grooves 73 are provided at intervals along the inner circumferential wall of the abutment 72. In order to prevent the anti-vibration ring 71 from rotating in the bearing groove 11, at least one inwardly recessed positioning groove 13 is provided on the inner wall of the bearing groove 11, one end of the positioning groove 13 extends through the opening of the bearing groove 11, and a convex strip 712 that can be inserted into the positioning groove 13 is provided on the circumferential outer wall of the anti-vibration ring 71. On the basis of ensuring that the anti-vibration ring 71 does not rotate, the fixing stability of the anti-vibration ring 71 is increased, and the vibration and noise of the bearing 3 are further reduced. In order to prevent the anti-vibration ring 71 from escaping from the bearing groove 11, an elastic clamp 8 that can clamp the two free ends of the anti-vibration ring 71 and prevent it from falling out of the bearing groove 11 is provided on the inner wall of the bearing groove 11 between the two free ends of the anti-vibration ring 71.

[0035] like Figures 7 to 10 As shown, the elastic clamp 8 includes a clamping groove 81 arranged on the inner wall of the bearing groove 11 with an upper and lower interval, and an annular elastic ring 82 is embedded between the clamping grooves 81. The elastic ring 82 is formed by continuous bending of metal. The left and right sides of the elastic ring 82 are respectively provided with convex points 83 protruding to both sides, and the two free ends of the anti-vibration ring 71 are respectively provided with notches 84 that can be matched with the corresponding convex points 83. When the bearing 3 is installed in the corresponding bearing groove 11, the side of the anti-vibration ring 71 without the abutment 72 is inserted into the gap between the bearing groove 11 and the bearing 3. In this process, the notch between the two free ends of the anti-vibration ring 71 is aligned with the elastic ring 82. When the chamfer 711 on the anti-vibration ring 71 contacts the convex point 83, it will squeeze the convex point 83 to force the connecting rods on the left and right sides of the elastic ring 82 to retract, so that the anti-vibration ring 71 can be smoothly inserted into the gap between the bearing groove 11 and the bearing 3. After the edges of the two free ends of the anti-vibration ring 71 near the chamfer 711 pass over the convex point 83, the notch 84 can be aligned with the convex point 83, and the connecting rods on the left and right sides of the elastic ring 82 are elastically reset to insert the convex point 83 into the corresponding notch 84, so that the anti-vibration ring cannot fall off, and the reliability of the bearing fixation is improved. When the bearing 3 needs to be removed, the inner groove 73 on the stopper 72 is hooked by a tool, and the anti-vibration ring 71 can be pulled out of the gap between the bearing groove 11 and the bearing 3 by force, so that the bearing 3 can be easily removed from the bearing groove 11.

[0036] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments. The above embodiments and the description are only to illustrate the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model will have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A novel outer rotor brushless DC motor, comprising a shaft sleeve (1) which is through-connected from top to bottom, characterized in that: An inner stator (2) is sleeved on the circumferential outer wall of the sleeve (1), a motor drive plate (5) is sleeved on the circumferential outer wall of the sleeve (1) located above the inner stator (2), a bearing (3) is embedded in the sleeve (1), a rotating shaft (4) is rotatably passed through the center of the bearing (3), the top end of the rotating shaft (4) extends out of the top opening of the sleeve (1), and the bottom end of the rotating shaft (4) extends out of the bottom opening of the sleeve (1), an outer rotor (6) is rotatably provided outside the inner stator (2), the outer rotor (6) is connected to the bottom end of the rotating shaft (4) and rotates synchronously, and an anti-vibration positioning member (7) is inserted between the bearing (3) and the inner wall of the sleeve (1) to quickly fix the bearing (3) in the sleeve (1).

2. A novel outer rotor DC brushless motor according to claim 1, characterized in that: Drive plate fixing ears (10) are arranged at intervals on the circumferential outer wall of the shaft sleeve (1) located above the motor drive plate (5); the motor drive plate (5) is detachably mounted on the shaft sleeve (1) by screws inserted into the drive plate fixing ears (10); and motor fixing ears (12) are arranged at intervals on the circumferential outer wall of the shaft sleeve (1) near the top.

3. The novel outer rotor DC brushless motor according to claim 1 is characterized in that: The inner stator (2) comprises an iron core (21) fixedly sleeved on the circumferential outer wall of the shaft sleeve (1) and a winding (22) wound in a slot of the iron core (21).

4. A novel outer rotor DC brushless motor according to claim 3, characterized in that: The outer rotor (6) includes an annular shell (61) surrounding the outer circumference of the iron core (21); a bottom plate (62) capable of closing the bottom end of the annular shell (61) is provided at the bottom end of the annular shell (61); an insertion hole (63) passes through the center of the bottom plate (62); the bottom end of the rotating shaft (4) is inserted into the insertion hole (63); and an annular magnet (64) is provided along the inner circumferential wall of the annular shell (61).

5. The novel outer rotor DC brushless motor according to claim 1 is characterized in that: Bearing grooves (11) are respectively provided in the openings at the top and bottom ends of the shaft sleeve (1); the two bearing grooves (11) have the same diameter and a diameter greater than the diameter of the circumferential inner wall of the shaft sleeve (1); and the bearings (3) are respectively installed in the bearing grooves (11).

6. A novel outer rotor DC brushless motor according to claim 5, characterized in that: The anti-vibration positioning member (7) comprises an anti-vibration ring (71) which is inserted between the circumferential outer wall of the bearing (3) and the inner wall of the bearing groove (11) in which it is located, the anti-vibration ring (71) being in a "C" shape, the height of the anti-vibration ring (71) being greater than the thickness of the bearing (3), a protruding abutment platform (72) being provided on the circumferential inner wall of the anti-vibration ring (71) which is higher than the bearing (3), the abutment platform (72) extending inwardly along the outer edge of the anti-vibration ring (71) to one side of the bearing (3) and abutting against the corresponding outer circumferential edge of the bearing (3), and an elastic clamping member (8) which can clamp the two free ends of the anti-vibration ring (71) and prevent it from falling out of the bearing groove (11) is provided on the inner wall of the bearing groove (11) between the two free ends of the anti-vibration ring (71).

7. A novel outer rotor DC brushless motor according to claim 6, characterized in that: The elastic clamp (8) comprises clamping grooves (81) arranged on the inner wall of the bearing groove (11) at an interval of one another, an annular elastic ring (82) is embedded between the clamping grooves (81), and the left and right sides of the elastic ring (82) are respectively provided with convex points (83) protruding toward the two sides, and the two free ends of the anti-vibration ring (71) are respectively provided with notches (84) that can be matched and clamped together with the corresponding convex points (83).

8. The novel outer rotor DC brushless motor according to claim 7 is characterized in that: Oblique chamfers (711) are provided at the corners of the two free ends of the anti-vibration ring (71) away from the opening of the bearing groove (11).

9. A novel outer rotor DC brushless motor according to any one of claims 6 to 8, characterized in that: At least one inwardly recessed positioning groove (13) is provided on the inner wall of the bearing groove (11), one end of the positioning groove (13) extends through the opening of the bearing groove (11), and a convex strip (712) capable of being inserted into the positioning groove (13) is provided on the circumferential outer wall of the anti-vibration ring (71).

10. The novel outer rotor DC brushless motor according to claim 4, characterized in that: A clamping tube (65) extending downward is provided along the circumference of the insertion hole (63); the bottom end of the rotating shaft (4) passes through the insertion hole (63) and is inserted into the clamping tube (65) through an interference fit.

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