Brushless motor and holder

Abstract

The utility model relates to the technical field of motors, in particular to a brushless motor and a holder. The brushless motor comprises a casing, a stator assembly, a mounting shaft, a rotor assembly and a rotating shaft. The installation shaft is fixedly installed in the machine shell, the stator assembly is fixedly installed on the installation shaft, and the rotor assembly is fixedly installed on the rotating shaft. A mounting insertion cavity extending in the axial direction is formed in the mounting shaft, the rotating shaft is inserted in the mounting insertion cavity, the stator assembly is located in the rotor assembly, and the rotating shaft can rotate in the mounting insertion cavity. And the circumferential surface of the rotating shaft is pre-clung to the side wall surface of the mounting insertion cavity, so that damping exists between the circumferential surface of the rotating shaft and the side wall surface of the mounting insertion cavity while the rotating shaft keeps rotating. According to the brushless motor, under the condition that normal rotation of the rotating shaft is guaranteed, the rotor assembly and the rotating shaft are rapidly braked through damping existing between the circumferential face of the rotating shaft and the side wall face of the installation insertion cavity after the brushless motor is powered off, and therefore rapid braking after the motor is powered off is achieved, braking is timely, and motor driving is accurate.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to a brushless motor and a pan / tilt platform. Background Art

[0002] The main structure of the brushless motor includes a multi-pole winding stator and a permanent magnet rotor. The working principle of the brushless motor is mainly based on electromagnetic induction control. When the electromagnet of the stator is energized, a rotating magnetic field is generated. The permanent magnet on the rotor is affected by the stator magnetic field and generates torque, thereby driving the rotor to rotate.

[0003] The existing brushless motors are difficult to brake quickly after power failure, the braking is not timely, and the motor drive is not accurate. Utility Model Content

[0004] The embodiment of the utility model provides a brushless motor and a pan / tilt head to solve the problems in the prior art that the brushless motor is difficult to brake quickly after power failure, the braking is not timely, and the motor driving is not accurate.

[0005] The utility model discloses a brushless motor, comprising a housing, a stator assembly, a mounting shaft, a rotor assembly and a rotating shaft; the mounting shaft is fixedly mounted in the housing, the stator assembly is fixedly mounted on the mounting shaft, and the rotor assembly is fixedly mounted on the rotating shaft;

[0006] An axially extending installation cavity is provided in the installation shaft, the rotating shaft is inserted in the installation cavity, the stator assembly is located in the rotor assembly, and the rotating shaft can rotate in the installation cavity;

[0007] The circumference of the rotating shaft is pre-tightly fitted with the side wall of the installation cavity, so that the rotating shaft can be kept rotatable while damping exists between the circumference of the rotating shaft and the side wall of the installation cavity.

[0008] Optionally, a mounting base is provided in the housing, and the mounting shaft is mounted on the mounting base; and / or

[0009] The main body of the rotating shaft is cylindrical, and is provided with two first openings which are oppositely arranged and extend along the axial direction.

[0010] Optionally, the stator assembly includes a coil support and a coil winding, the coil support is fixedly mounted on the mounting shaft, and the coil winding is wound on the coil support.

[0011] Optionally, the brushless motor includes a connecting wire and a circuit board, and the circuit board is located outside the casing; a through slot is opened on the side wall of the casing, one end of the connecting wire is electrically connected to the coil winding, and is led out of the casing through the through slot to be electrically connected to the circuit board.

[0012] Optionally, a Hall sensor is provided on the circuit board, and the Hall sensor is used to detect the rotation position of the rotor assembly.

[0013] Optionally, a mounting base is provided in the housing, and the mounting shaft is mounted on the mounting base; a second opening is provided on the mounting base, and the connecting wire is led to the through slot after passing through the second opening.

[0014] Optionally, an anti-rust layer is provided on the surface of the rotating shaft and / or the mounting shaft.

[0015] Optionally, the anti-rust layer is a nickel metal layer.

[0016] Optionally, the rotor assembly includes a shell and an annular permanent magnet; the shell is fixedly mounted on the rotating shaft, and the annular permanent magnet is fixedly mounted on the inner wall of the shell; and the stator assembly is located in the annular permanent magnet.

[0017] The utility model also discloses a pan head, comprising the brushless motor as described above.

[0018] Compared with the prior art, the brushless motor provided by the embodiment of the utility model has the beneficial effect that: the motor of the utility model is provided with a rotating shaft and a mounting shaft, the mounting shaft is installed in the housing, the stator assembly is installed on the rotating shaft, and the rotor assembly is installed on the rotating shaft. Among them, an axially extending mounting cavity is opened in the mounting shaft, the rotating shaft is inserted in the mounting cavity, and the circumferential surface of the rotating shaft is pre-tightened and fitted with the side wall surface of the mounting cavity, and the rotating shaft is kept rotatable while damping exists between the circumferential surface of the rotating shaft and the side wall surface of the mounting cavity. In this way, the normal rotation of the rotating shaft can be ensured, and at the same time, the damping between the circumferential surface of the rotating shaft and the side wall surface of the mounting cavity allows the rotor assembly and the rotating shaft to brake quickly after the brushless motor is powered off, thereby achieving rapid braking after the motor is powered off, timely braking, and precise motor driving. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The technical solution of the utility model will be further described in detail below with reference to the accompanying drawings and embodiments, in which:

[0020] Figure 1 Schematic diagram of a brushless motor according to an embodiment of the utility model;

[0021] Figure 2 is a cross-sectional view of a brushless motor according to an embodiment of the utility model;

[0022] Figure 3 It is an exploded schematic diagram of the brushless motor of the embodiment of the utility model;

[0023] Figure 4 It is an exploded schematic diagram of the installation shaft and the rotating shaft of the embodiment of the utility model;

[0024] Figure 5 It is another exploded schematic diagram of the installation shaft and the rotating shaft of the embodiment of the utility model;

[0025] Figure 6It is another schematic diagram of the brushless motor according to the embodiment of the utility model.

[0026] The reference numerals in the figures are:

[0027] 1. Casing; 11. Through slot; 2. Stator assembly; 21. Coil bracket; 211. Second mounting hole; 22. Coil winding; 3. Mounting shaft; 31. Mounting cavity; 32. First plug-in end; 4. Rotor assembly; 41. Shell; 411. Third mounting hole; 42. Ring permanent magnet; 5. Rotating shaft; 51. Main body; 511. First opening; 52. Transmission output end; 6. Mounting base; 61. Second opening; 62. First mounting hole; 7. Connecting wire; 8. Circuit board; 81. Hall sensor; 9. Screw. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, a preferred embodiment of the present utility model is described in detail.

[0029] The utility model provides a brushless motor. Figures 1 to 5 As shown, the brushless motor includes a housing 1, a stator assembly 2, a mounting shaft 3, a rotor assembly 4 and a rotating shaft 5. The mounting shaft 3 is fixedly mounted in the housing 1, the stator assembly 2 is fixedly mounted on the mounting shaft 3, and the rotor assembly 4 is fixedly mounted on the rotating shaft 5. An axially extending mounting cavity 31 is provided in the mounting shaft 3, the rotating shaft 5 is inserted in the mounting cavity 31, the stator assembly 2 is located in the rotor assembly 4, and the rotating shaft 5 can rotate in the mounting cavity 31.

[0030] The circumference of the rotating shaft 5 is pre-tightly fitted with the side wall of the installation cavity 31 so that the rotating shaft 5 can be kept rotatable while damping exists between the circumference of the rotating shaft 5 and the side wall of the installation cavity 31 .

[0031] The motor of the utility model is provided with a rotating shaft 5 and a mounting shaft 3, wherein the mounting shaft 3 is mounted in a housing 1, the stator assembly 2 is mounted on the rotating shaft 5, and the rotor assembly 4 is mounted on the rotating shaft 5. Among them, an axially extending mounting cavity 31 is provided in the mounting shaft 3, the rotating shaft 5 is inserted in the mounting cavity 31, and the circumference of the rotating shaft 5 is pre-tightly fitted with the side wall surface of the mounting cavity 31, and the rotating shaft 5 is kept rotatable while damping exists between the circumference of the rotating shaft 5 and the side wall surface of the mounting cavity 31. In this way, the rotating shaft 5 can be ensured to rotate normally, and at the same time, the rotor assembly 4 and the rotating shaft 5 can be quickly braked after the brushless motor is powered off through the damping between the circumference of the rotating shaft 5 and the side wall surface of the mounting cavity 31, thereby realizing rapid braking after the motor is powered off, timely braking, and precise motor driving.

[0032] The circumference of the rotating shaft 5 and the side wall of the mounting cavity 31 are pre-tightened and fitted, so that the circumference of the rotating shaft 5 and the side wall of the mounting cavity 31 are in contact and have a certain, mutually squeezing force between them. The magnitude of this force will not prevent the rotating shaft 5 from rotating in the mounting cavity 31, and at the same time, a certain friction force can be generated due to the pre-tightening and fitting between the two, so that there is damping between the circumference of the rotating shaft 5 and the side wall of the mounting cavity 31. In this way, after power failure, due to the existence of damping, the rotating shaft 5 can stop rotating quickly, thereby realizing rapid braking of the motor. The degree of pre-tightening and fitting between the circumference of the rotating shaft 5 and the side wall of the mounting cavity 31 after assembly can be adjusted according to actual needs by adjusting the diameter size relationship between the rotating shaft 5 and the mounting cavity 31, which will not be repeated here.

[0033] Since the circumferential surface of the rotating shaft 5 and the side wall surface of the mounting cavity 31 are always pre-tightened and fit, there is always damping between the rotating shaft 5 and the mounting cavity 31 when the rotating shaft 5 rotates. Therefore, the brushless motor of the utility model has a low speed, and is suitable for devices that do not require high speed or even require low speed, such as the drive of the pitch axis and yaw axis on a two-axis gimbal, or the drive of the pitch axis, yaw axis, and roll axis on a three-axis gimbal. These gimbal devices only require motor drive to adjust the shooting angle, and do not require high motor speed, but have high requirements for the timeliness of motor braking and driving accuracy. Therefore, the brushless motor of the utility model is particularly suitable for these gimbal devices. Of course, the brushless motor of the utility model can also be applied to other devices that do not require high speed or even require low speed.

[0034] When the stator assembly 2 is energized, a magnetic field is generated, and the permanent magnet on the rotor assembly 4 is acted upon by the magnetic field of the stator assembly 2 to generate torque, thereby driving the rotor assembly 4 to rotate. Since the rotor assembly 4 is mounted on the rotating shaft 5, the rotor assembly 4 rotates together with the rotating shaft 5. The rotating shaft 5 is also a transmission output component of the brushless motor, and can be used to connect with an external driving object to realize the driving of the driving object by the brushless motor.

[0035] Specifically, the main body 51 of the rotating shaft 5 is cylindrical, and is provided with two first openings 511 oppositely disposed and extending along the axial direction, so that the rotating shaft 5 and the mounting shaft 3 can be easily assembled.

[0036] Further, a mounting base 6 is provided in the housing 1, and the mounting shaft 3 is mounted on the mounting base 6. The mounting base 6 is provided to provide a mounting position for the mounting shaft 3, which is convenient for the installation of the mounting shaft 3 and ensures that the mounting shaft 3 can be firmly installed in the housing 1. Specifically, a first mounting hole 62 with a waist-shaped cross section can be provided on the mounting base 6, and one end of the mounting shaft 3 installed on the mounting base 6 is provided as a first plug-in end 32 with a waist-shaped cross section, and the first plug-in end 32 is plugged into the first mounting hole 62, and the first plug-in end 32 can be fixed in the first mounting hole 62 by riveting and / or glue. The mounting base 6 can be fixedly installed in the housing 1 by two screws 9 arranged opposite to each other.

[0037] The stator assembly 2 includes a coil support 21 and a coil winding 22. The coil support 21 is fixedly mounted on the mounting shaft 3, and the coil winding 22 is wound on the coil support 21. After the coil winding 22 is energized, the stator assembly 2 generates a magnetic field. The coil support 21 is a motor core, which is usually formed by stacking a plurality of silicon steel sheets, and the coil winding 22 is then wound in a receiving groove of the core. The coil of the coil winding 22 is a copper wire. A second mounting hole 211 is provided at the axis of the coil support 21, and the coil support 21 is sleeved on the mounting shaft 3 through the second mounting hole 211 to achieve the installation and fixation of the coil support 21. The mounting shaft 3 can be fixed in the second mounting hole 211 by riveting and / or glue.

[0038] like Figures 1 to 3 , Figure 6 As shown, the brushless motor includes a connecting wire 7 and a circuit board 8, and the circuit board 8 is located outside the housing 1; a through slot 11 is provided on the side wall of the housing 1, and one end of the connecting wire 7 is electrically connected to the coil winding 22, and is led out to the outside of the housing 1 through the through slot 11 to be electrically connected to the circuit board 8. The stator assembly 2 is energized by the connecting wire 7, and the through slot 11 provided on the side wall of the housing 1 facilitates the connection wire 7 to be led out from the housing 1 and connected to the circuit board 8. The circuit board 8 is arranged outside the housing 1 to facilitate the circuit connection of the circuit board 8 and the installation and fixation of the circuit board 8 itself. The circuit board 8 can be installed on the side of the housing 1 away from the transmission output end 52 of the rotating shaft 5 by gluing, or it can be installed in the device used when the brushless motor is used, which is not specifically limited here. Of course, the brushless motor can also exist independently without the circuit board 8, and only needs to be connected to the circuit board 8 when it is used. A Hall sensor 81 is provided on the circuit board 8, and the Hall sensor 81 is used to detect the rotation position of the rotor assembly 4. The Hall sensor 81 senses the change in magnetic field when the rotor assembly 4 rotates, thereby detecting the relative position of the rotor assembly 4 relative to the stator assembly 2, so that the brushless motor can accurately control the current and current direction of the coil winding 22. Specifically, four Hall sensors 81 are provided on the circuit board 8, and the central angle formed by adjacent Hall sensors 81 in the four Hall sensors 81 is 90°.

[0039] Furthermore, the mounting base 6 is provided with a second opening 61, and the connecting wire 7 is led to the through slot 11 after passing through the second opening 61. The second opening 61 is provided to facilitate the leading out wiring of the connecting wire 7.

[0040] An anti-rust layer is provided on the surface of the rotating shaft 5 and / or the mounting shaft 3. The anti-rust layer can prevent the surface of the rotating shaft 5 and / or the mounting shaft 3 from rusting. The material of the rotating shaft 5 and / or the mounting shaft 3 can be medium carbon steel. Specifically, the anti-rust layer is a nickel metal layer. The nickel metal layer can be plated on the surface of the rotating shaft 5 and / or the mounting shaft 3 by electroplating.

[0041] Furthermore, the rotor assembly 4 includes a shell 41 and an annular permanent magnet 42; the shell 41 is fixedly mounted on the rotating shaft 5, and the annular permanent magnet 42 is fixedly mounted on the inner wall of the shell 41; the stator assembly 2 is located in the annular permanent magnet 42. The shell 41 provides the installation of the annular permanent magnet 42 and the connection between the rotor assembly 4 and the rotating shaft 5. The stator assembly 2 is located in the annular permanent magnet 42, and the two form a magnetic field to generate torque, so that the rotor assembly 4 rotates. The specific rotation principle is conventional technology and will not be repeated here. The annular permanent magnet 42 can provide a magnetic field in all directions in 360°, so that the stator assembly 2 is completely placed in the magnetic field of the annular permanent magnet 42. One end of the rotating shaft 5 connected to the shell 41 passes through the shell 41 and extends out as a transmission output end 52. The housing 41 may be provided with a third mounting hole 411 having a waist-shaped cross section, and the transmission output end 52 is configured to have a waist-shaped cross section. The transmission output end 52 is inserted into the third mounting hole 411, and the transmission output end 52 may be fixed in the third mounting hole 411 by riveting and / or gluing. The transmission output end 52 extends through the housing 41 and can be further connected to a driving object to realize drive transmission of the brushless motor.

[0042] The utility model also discloses a gimbal, including the brushless motor. The brushless motor is installed in the gimbal and connected to a driving object such as a pitch axis, a yaw axis, a roll axis, etc., to drive the pitch axis, the yaw axis, and the roll axis to rotate. Since the gimbal of the utility model has the brushless motor, it also has the technical effects of the brushless motor, which will not be described in detail.

[0043] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present utility model rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present utility model.

Claims

1. A brushless motor, characterized in that: It includes a housing, a stator assembly, a mounting shaft, a rotor assembly and a rotating shaft; the mounting shaft is fixedly mounted in the housing, the stator assembly is fixedly mounted on the mounting shaft, and the rotor assembly is fixedly mounted on the rotating shaft; An axially extending installation cavity is provided in the installation shaft, the rotating shaft is inserted in the installation cavity, the stator assembly is located in the rotor assembly, and the rotating shaft can rotate in the installation cavity; The circumferential surface of the rotating shaft is pre-tightly fitted with the side wall surface of the installation cavity, so that the rotating shaft can remain rotatable while damping exists between the circumferential surface of the rotating shaft and the side wall surface of the installation cavity.

2. The brushless motor according to claim 1, characterized in that: A mounting base is provided in the housing, and the mounting shaft is mounted on the mounting base; and / or The main body of the rotating shaft is cylindrical, and is provided with two first openings which are oppositely arranged and extend along the axial direction.

3. The brushless motor according to claim 1, characterized in that: The stator assembly comprises a coil support and a coil winding. The coil support is fixedly mounted on the mounting shaft, and the coil winding is wound on the coil support.

4. The brushless motor according to claim 3, characterized in that: The brushless motor includes a connecting wire and a circuit board, and the circuit board is located outside the casing; a through slot is opened on the side wall of the casing, one end of the connecting wire is electrically connected to the coil winding, and is led out of the casing through the through slot to be electrically connected to the circuit board.

5. The brushless motor according to claim 4, characterized in that: A Hall sensor is arranged on the circuit board, and the Hall sensor is used to detect the rotation position of the rotor assembly.

6. The brushless motor according to claim 5, characterized in that: A mounting base is arranged in the housing, and the mounting shaft is mounted on the mounting base; a second opening is opened on the mounting base, and the connecting wire is led to the through slot after passing through the second opening.

7. The brushless motor according to any one of claims 1 to 6, characterized in that: An anti-rust layer is provided on the surface of the rotating shaft and / or the mounting shaft.

8. The brushless motor according to claim 7, characterized in that: The anti-rust layer is a nickel metal layer.

9. The brushless motor according to any one of claims 1 to 6, characterized in that: The rotor assembly comprises a shell and an annular permanent magnet; the shell is fixedly mounted on the rotating shaft, and the annular permanent magnet is fixedly mounted on the inner side wall of the shell; the stator assembly is located in the annular permanent magnet.

10. A pan / tilt head, characterized in that: Comprising the brushless motor as claimed in any one of claims 1 to 9.

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