WO2020000854A1 - Electric motor, pan-tilt, camera assembly and unmanned aerial vehicle - Google Patents

Abstract

Disclosed are an electric motor, a pan-tilt, a camera assembly and an unmanned aerial vehicle. The electric motor comprises a stator (61); a rotor (62) which is sleeved on the stator (61) and can rotate about the rotation axis of the rotor (62) relative to the stator (61); and a first linear Hall element (63) and a second linear Hall element (64), which are both fixedly mounted to the stator (61), wherein the plane where the first linear Hall element (63) and the second linear Hall element (64) are located is perpendicular to the rotation axis, and in the plane, the mechanical angle α between the first linear Hall element (63) and a magnetomotive force axis (Fa) of a first phase winding of the stator (61) satisfies -30° ≤ 360° - α×p - 90° ≤ 30°, and the mechanical angle β between the second linear Hall element (64) and a magnetomotive force axis (Fb) of a second phase winding of the stator (61) satisfies -30° ≤ 360° - β×p - 90° ≤ 30°, where p is the number of pole pairs of the rotor. As a result, the angle of the electric motor can be precisely estimated merely by means of two linear Hall elements, reducing the cost and facilitating the realization of a miniaturized design.

Description

Motor, gimbal, camera module and drone

This application claims the priority of a Chinese patent application filed on June 25, 2018 with the Chinese Patent Office, application number 2018209940726, and application name "Motor, PTZ, Camera Module and Drone", the entire contents of which are incorporated by reference. In this application.

Technical field

The present application relates to the technical field of drones, and in particular, to a motor, a gimbal, a camera component, and a drone.

Background technique

Unmanned aerial vehicle (UAV) is an unmanned aircraft that controls flight attitude through radio remote control equipment and built-in programs. Due to its advantages such as maneuverability, fast response, unmanned operation, and low operating requirements, etc. , Has been widely used in aerial photography, plant protection, power inspection, disaster relief and many other fields.

With the development of drones, the application of gimbals on drones has become more and more widespread. At present, the way to control the pan / tilt is generally to use at least three Hall sensors and magnetic encoders to determine the angle of the motor in the pan / tilt, and then precisely control the pan / tilt.

However, in the process of implementing the present application, the inventors found that at present, when detecting the angle of a motor, a magnetic encoder is needed to achieve the detection accuracy required by the gimbal, and the cost of using a magnetic encoder is high, and it is easy to cause The increase in the structure of the motor is not conducive to achieving a miniaturized design.

Summary of the invention

In view of this, the embodiments of the present application provide a motor, a gimbal, a camera component and a drone, which can accurately estimate the angle of the motor without the need for a magnetic encoder, thereby reducing costs and being beneficial to Achieve miniaturized design.

In order to solve the above technical problem, a technical solution adopted in the present application is to provide a motor, including:

stator;

A rotor sleeved on the stator and rotatable relative to the stator about a rotation axis of the rotor;

The first linear Hall element and the second linear Hall element are both fixedly mounted on the stator, and a plane where the first linear Hall element and the second linear Hall element are located is perpendicular to the rotation axis, and , On the plane, the mechanical angle α between the first linear Hall element and the magnetomotive force axis of the first phase winding of the stator satisfies: -30 ° ≦ 360 ° -α × p-90 ° ≤30 °, the mechanical angle β between the second linear Hall element and the magnetomotive force axis of the second phase winding of the stator satisfies: -30 ° ≤360 ° -β × p-90 ° ≤30 ° Where p is the number of pole pairs of the rotor.

Optionally, the mechanical angle α is equal to the mechanical angle β.

Optionally, a mechanical angle γ between the first linear Hall element and the second linear Hall element is 123 °.

Optionally, the sensitivities of the first linear Hall element and the second linear Hall element are 11 mV / mT.

Optionally, the stator includes:

A stator base comprising a base and a cylinder provided in a middle portion of the base;

An iron core, which is sleeved outside the cylinder; and,

A coil wound around the iron core;

The rotor is mounted on the cylinder, and the first linear Hall element and the second linear Hall element are fixedly mounted on a surface of the base facing the core.

Optionally, the stator includes:

A stator base comprising a base and a cylinder provided in a middle portion of the base;

An iron core, which is sleeved outside the cylinder body;

A coil wound around the core; and,

An electric adjustment board, which is sleeved on the cylinder and is fixedly installed on the base;

The rotor is installed in the cylinder body, and the first linear Hall element and the second linear Hall element are fixedly installed on a surface of the ESC facing the iron core.

Optionally, the stator further includes: an electric adjustment plate pressing piece, which is disposed between the iron core and the electric adjustment plate, and is used for fixing the electric adjustment plate piece to the base.

Optionally, the iron core includes a plurality of teeth, and the surface of the pressing plate of the electrical adjustment plate is provided with protrusions, and the protrusions are clamped between two of the teeth.

Optionally, the rotor includes:

A casing including an upper cover and a casing, the casing being sleeved on the outer periphery of the iron core;

A permanent magnet, which is disposed on a surface of the casing facing the iron core and leaves a gap with the iron core;

One end of the rotating shaft is fixedly installed in the upper cover, and the other end is rotatably installed in the cylinder.

Optionally, a height difference between the first linear Hall element and the second linear Hall element and the permanent magnet is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.

Optionally, the permanent magnet has a ring structure and is integrally injection-molded from a magnetic material.

Optionally, the rotation axis is an optical axis.

Optionally, a pre-pressure hole is provided at one end of the rotating shaft installed in the cylinder.

In order to solve the above technical problem, a technical solution adopted in the present application is to provide a gimbal, which includes the motor as described above.

In order to solve the above technical problem, a technical solution adopted in the present application is to provide a camera component, which includes a pan / tilt as described above.

In order to solve the above technical problem, a technical solution adopted in the present application is to provide an unmanned aerial vehicle, which includes the camera component as described above.

The beneficial effect of the embodiment of the present application is that the motor provided by the embodiment of the present application detects the angle of the motor through the first linear Hall element and the second linear Hall element, and is specifically determined according to the magnetomotive force axis of the first phase winding thereof. The installation position of the first linear Hall element and determining the installation position of the second linear Hall element according to the magnetomotive force axis of the second phase winding thereof can enable the first linear Hall element and the second linear Hall element The amplitude sensed by the Hall element meets the control accuracy requirements of the gimbal. Therefore, the motor provided in the embodiment of the present application can accurately estimate the angle of the motor through only two linear Hall elements, which can reduce costs. Conducive to achieving miniaturized design.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are used in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are just some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a three-dimensional structure of a camera module provided by one embodiment of the present application; FIG.

2 is an exploded view of the gimbal in the camera module shown in FIG. 1;

3 is an exploded view of the gimbal shown in FIG. 2 from another perspective;

4 is an exploded view of a third motor in the pan / tilt shown in FIG. 2;

5 is an exploded view of the third motor shown in FIG. 4 from another perspective;

6 is a transverse cross-sectional view of the third motor shown in FIG. 5, in which only an iron core, a permanent magnet, and a casing are shown;

7 is a transverse cross-sectional view of the third motor shown in FIG. 5, wherein the permanent magnet and the casing are omitted;

FIG. 8 is a schematic diagram of an angular relationship between a first linear Hall element and a magnetomotive force axis of a first phase winding provided in an embodiment of the present application.

detailed description

In order to facilitate understanding of the present application, the present application will be described in more detail below with reference to the drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it may be directly on the other element, or there may be one or more centered elements in between. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or one or more intervening elements may be present therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

Unless otherwise defined, all technical and scientific terms used in this specification have the same meanings as commonly understood by those skilled in the technical field of this application. The terms used in the description of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application.

In addition, the technical features involved in the embodiments of the present application described below can be combined with each other as long as they do not constitute a conflict with each other. The term "and / or" used in this specification includes any and all combinations of one or more of the associated listed items.

The motor provided in the embodiment of the present application is a motor that can accurately estimate the angle of the motor (or the position of the rotor of the motor) by using only two linear Hall elements, and is suitable for any application field of mechatronics, especially As a power device, it is applied to any movable device. For example, the movable device may include, but is not limited to, unmanned aerial vehicles (UAVs), ships, robots, etc .; or it may also be used as a control device. It can be used on the PTZ to meet the control precision requirements of the PTZ. The motor provided in the embodiment of the present application can accurately estimate the angle of the motor by only two linear Hall elements, which can reduce the cost and facilitate the realization of a compact design.

Further, an embodiment of the present application further provides a pan / tilt head including the motor and a camera component. The gimbal can be used to carry any type of camera device to form the camera component, and the camera component can be applied to mobile devices such as drones, unmanned ships, and robots.

Furthermore, an embodiment of the present application further provides a drone including the camera component. The drone may be any type of unmanned aerial vehicle, which may include, but is not limited to, a single-rotor drone, a multi-rotor Rotor drone, tilt rotor drone, etc.

Specifically, the motor, the gimbal, the camera module, and the drone provided in the embodiments of the present application will be described in detail below with reference to the accompanying drawings of the description.

FIG. 1 is a schematic structural diagram of a camera module according to an embodiment of the present application. The camera module 300 can be installed on the body of a drone.

Specifically, referring to FIG. 1, the camera module 300 includes: a pan / tilt head 100 and a camera 200 installed on the pan / tilt head 100. The gimbal 100 is used to be fixedly mounted on the body of the drone and to fix the camera device 200. By precisely controlling the pan / tilt head 100, the posture of the camera device 200 (for example, changing the height, tilting angle, and / or direction of the camera device 200) can be arbitrarily adjusted and the camera device 200 can be stably maintained In the set posture. The camera device 200 includes at least one camera for collecting image data. The camera may be any type of lens, for example, it may be a single camera, a panoramic camera, or the like.

Please refer to FIG. 2 and FIG. 3 together. The pan / tilt head 100 includes a lens barrel 10, a first motor 20, a first connecting arm 30, a second motor 40, a second connecting arm 50, a third motor 60, and a third The connecting arm 70 and the shock absorbing component 80. Wherein, in this embodiment, the structures of the first motor 20, the second motor 40, and the third motor 60 are substantially similar, and all of them include a stator and are sleeved on the stator and can be wound around the stator. Stator rotating rotor.

The lens barrel 10 is substantially cylindrical, and a receiving space is formed in the lens barrel 10 for receiving the camera 200 and a corresponding control circuit board. The lens barrel 10 is fixedly mounted on a stator of the first motor 20, and can rotate with the first motor 20 about a first rotation axis, so that the camera 200 can rotate about the first rotation axis.

The rotor of the first motor 20 is fixedly connected to the rotor of the second motor 40 through the first connecting arm 30. The second motor 40 can drive the first motor 20, the lens barrel 10, and the rotor. The imaging device 200 rotates around a second rotation axis. Wherein, the structure formed by the rotor of the first electric machine 20, the first connecting arm 30, and the rotor of the second electric machine 40 is substantially an "L" shape, so that the second rotation axis and the first The axis of rotation is vertical.

The stator of the second motor 40 is fixedly connected to the stator of the third motor 60 through the second connecting arm 50. The third motor 60 can drive the second motor 40, the first motor 20, The lens barrel 10 and the imaging device 200 rotate around a third rotation axis. Wherein, the structures formed by the stator of the second electric machine 40, the second connecting arm 50, and the stator of the third electric machine 60 are also substantially "L" -shaped, and the third rotation axis and the first rotation axis are respectively A rotation axis is perpendicular to the second rotation axis.

An upper end portion of the third connecting arm 70 is fixedly connected to a rotor of the third motor 60. The shock absorbing component 80 is fixedly installed at the lower end of the third connecting arm 70 and is disposed in parallel with the second motor 40 and the second connecting arm 50 for mounting the gimbal 100 on the The body of the drone is described, and at the same time, the suspension performance of the PTZ 100 is improved.

It can be understood that, in this embodiment, the lens barrel 10 is fixedly mounted on a stator of the first motor 20, and a rotor of the first motor 20 is connected to the stator through the first connecting arm 30. The rotor of the second electric machine 40 is fixedly connected, and the stator of the second electric machine 40 is fixedly connected to the stator of the third electric machine 60 through the second connecting arm 50. This is only one of the embodiments, and in practical applications The first motor 20, the second motor 40, and the third motor 60 may also be connected by other links, as long as the camera device 200 can be rotated about the first vertical axis of rotation, the second The rotation axis and the third rotation axis may be rotated. For example, in other embodiments, the lens barrel 10 may also be mounted on a rotor of the first motor 20, and a stator of the first motor 20 is connected to the rotor through the first connecting arm 30. The rotor of the second motor 40 is connected; or, the lens barrel 10 is mounted on the stator of the first motor 20, and the rotor of the first motor 20 is connected to the second motor 40 through the first connecting arm 30. The stator of the second electric machine 40 is fixedly connected to the stator or the rotor of the third electric machine 60 through the second connecting arm 50.

It can also be understood that, in this embodiment, the pan / tilt head 100 includes three motors (ie, the first motor 20, the second motor 40, and the third motor 60), so as to enable the camera device 200 to run around. The first axis of rotation, the second axis of rotation, and the third axis of rotation rotate; in other embodiments, the head 100 may also include more or fewer motors, for example, the motors in the head 100 The number can be one, two, four, and so on. This embodiment of the present application does not specifically limit this.

Specifically, in this embodiment, the structures of the first motor 20, the second motor 40, and the third motor 60 are substantially similar. In the following, only the third motor 60 is used as an example to describe the motor provided in the embodiment of the present application in detail.

Please refer to FIG. 4 and FIG. 5 together. The third motor 60 includes a stator 61, a rotor 62, a first linear Hall element 63, and a second linear Hall element 64.

The rotor 62 is sleeved on the stator 61 and is rotatable around the stator 61. The rotor 62 has a rotation axis (that is, the third rotation axis); the first linear Hall element 63 and the The second linear Hall element 64 is fixedly mounted on the stator 61, and a plane where the first linear Hall element 63 and the second Hall element 64 are located is perpendicular to the third rotation axis, and is used for The leakage magnetic field strength of the rotor 62 is sensed so that the control unit of the third electric machine 60 determines the position of the rotor 62 (or the angle of the third electric machine 60) based on the leakage magnetic field strength.

Specifically, the stator 61 includes: a stator base 610, an iron core 612, a coil 614, a bearing 616, an ESC plate 618, and an ESC plate 619.

The bearing 616 is provided in the stator base 610 for mounting the rotor 62; the iron core 612 is sleeved outside the stator base 610; and the coil 614 is wound around the iron core 612 to constitute The first-phase winding, the second-phase winding, and the third-phase winding of the third electric machine 60; the electric adjustment plate 618 is sleeved with the stator base 610, and is fixedly installed in the place by the electric adjustment plate pressing piece 619. On the stator base 610, the first linear Hall element 63 and the second Hall element 64 are both fixedly mounted on a surface of the electrical adjustment plate 618 facing the iron core 612.

The stator base 610 is installed at an end of the third connecting arm 50 away from the second motor 40. In order to ensure the stability of the gimbal 100, the stator base 610 and the third connecting arm 50 (And the stator base of the second motor 40) are integrally formed. The stator base 610 includes a base 6101 and a cylindrical body 6102 provided in a middle portion of the base 6101. The base 6101 and the cylindrical body 6102 may be integrally formed. A bearing cavity 6100 is formed in the cylindrical body 6102, and the bearing 616 is received in the bearing cavity 6100 for installing the rotor 62. Among them, in order to ensure the coaxiality of the stator 61 and the rotor 62, the bearing 616 includes two, and the two bearings 616 are respectively housed at both ends of the bearing cavity 6100 (that is, the bearing cavity 6100 top and bottom). In addition, in order to improve the protection level of the third motor 60, the bearing 616 can be a stainless steel bearing or a ceramic bearing, which can be selected according to the actual application situation.

The iron core 612 includes a body and an insulating layer covering a surface of the body. The body is sleeved outside the cylinder body 6102, and the insulation layer is used to isolate the body and the coil 614 to prevent the third motor 60 from being short-circuited. In practical applications, the body may be formed by stacking materials that are easily magnetized (such as steel, nickel, iron, etc.), and the insulating layer may be formed of any material with insulating properties, such as: plastic, digital powder, 3M860E Powder and so on. In order to reduce the weight of the motor, the body may be made of silicon steel sheets or silicon steel sheets stacked, and the insulation layer may be formed of 3M860E powder coated on the surface of the body.

Specifically, in this embodiment, as shown in FIG. 6, the body includes 12 teeth portions 6120 for winding the coil 614, and the width or average width t of each of the teeth portions 6120 may be set as 1.00 mm, correspondingly, the thickness or average thickness T of the insulating layer may be set to 0.15 mm. Wherein, in some embodiments, in order to be able to wind more turns of the coil and facilitate the arrangement of the coils 614, each of the teeth 6120 may have a ladder shape, and the width of the teeth 6120 along the radial direction of the body is Gradually increase from the inside out. In addition, in practical applications, the outer diameter D of the iron core 612 may be set to be greater than or equal to 16 mm and less than or equal to 20 mm (that is, 16 mm ≤ D ≤ 20 mm); the height of the iron core 612 may be set to be greater than or It is equal to 3 mm and less than or equal to 6 mm.

Please refer to FIG. 4 or FIG. 5 again, the coil 614 includes at least one layer, which may be formed by winding a single or multiple enameled copper wires around each of the teeth 6120. Among them, windings of different phases can be formed according to different ways of winding the coil 614. In this embodiment, after the coil 614 is wound around the tooth portion 6120, a first phase winding and a second phase can be formed. The windings and the third-phase windings, and the angles between the first-phase windings, the second-phase windings, and the third-phase windings are 120 ° with each other. In practical applications, the diameter of the single or multiple enameled copper wires after removing the varnish can be set to be greater than or equal to 0.15 mm and less than or equal to 0.25 mm, and in order to increase the torque of the third motor 60, The number of turns can be set to be: 30 or more and 40 or less.

The electric adjustment plate 618 is sleeved on the cylinder 6102 and is installed on the base 6101. The ESC 618 may be any type of circuit board, for example, it may be a flexible circuit board, and electronic components for controlling the third motor 60, such as capacitors, resistors, Chips and so on.

The electric adjustment plate pressing piece 619 is disposed between the iron core 612 and the electric adjustment plate 618 and is used to fix the electric adjustment plate 618 to the stator base 610. The electric plate pressing plate 619 is provided with a groove 6190 to allow the first linear Hall element 63 and the second linear Hall element 64 to pass through the electric plate pressing plate 619. A strip-shaped protrusion 6192 is also provided on a surface of the electric adjustment plate pressing piece 619 facing the iron core 612, and the protrusion 6192 is clamped between two of the tooth portions 6120 for The iron core 612 is limited to prevent the iron core 612 from deviating from the original position, thereby ensuring the reliability of the angle detection of the motor.

It can be understood that, in this embodiment, in order to reduce the weight of the third motor 60 and facilitate the miniaturization design, the ESC 618 is a flexible circuit board, and is further fixed by the ESC plate 619 The flexible circuit board. In some other embodiments, the ESC 618 may be a ceramic circuit board, a printed circuit board, or the like. At this time, the ESC pressing plate 619 may also be omitted.

It can also be understood that, in this embodiment, the first linear Hall element 63 and the second linear Hall element 64 are integrated on the ESC 618, so that the third motor 60 The structure is more compact. In some other embodiments, the ESC 618 may be omitted, and the first linear Hall element 63 and the second linear Hall element 64 may be directly fixed to the base of the stator base 610. 6101.

Please continue to refer to FIG. 4 and FIG. 5 together. The rotor 62 includes a casing 620, a permanent magnet 622, and a rotating shaft 624. The casing 620 is rotatably sleeved on the outer periphery of the iron core 612; the permanent magnet 622 is disposed on a surface of the casing 620 facing the iron core 612, and a space is left between the casing 620 and the iron core 612 Clearance; one end of the rotating shaft 624 is fixed to the casing, and the other end is rotatably installed in the cylinder 6102 through the bearing 616. Therefore, under the drive of the rotation shaft 624, the casing 620 and the permanent magnet 622 can rotate around the stator 61, and its rotation axis (that is, the third rotation axis) is the rotation Centerline of axis 624.

The cabinet 620 includes an upper cover 6201 and a housing 6202 formed by extending downward from the upper cover 6201 (i.e., extending toward the base 6101). A shaft hole 6200 is provided in a middle portion of the upper cover 6201 for mounting the rotating shaft 624. The upper cover 6201 is further provided with a contact portion on a surface facing the stator base 610, and the shaft hole 6200 penetrates the contact portion. After the rotor 62 is mounted to the stator 61, the abutting portion abuts on a bearing 616 (ie, a bearing 616 near the upper cover 6201) located at the top of the bearing cavity 6100. The housing 6202 has a cylindrical structure and is sleeved on the outer periphery of the iron core 612. In practical applications, the casing 620 may be made of high-efficiency magnetically permeable materials such as 10 # steel and 20 # steel.

The permanent magnet 622 is disposed on a surface of the casing 6202 facing the iron core 612, and a gap is left between the permanent magnet 622 and the iron core 612. Specifically, in this embodiment, the permanent magnet 622 has a ring structure, and can be integrally injection-molded from a magnetic material. Wherein, the material of the permanent magnet 622 may be magnetic materials such as ferrite, neodymium-iron-boron, samarium-cobalt permanent magnet material (SmCo), and the residual magnetic induction intensity Br thereof may be greater than or equal to 680 mT and less than or equal to 810 mT, as long as The amplitude peak deviation of a single Hall element can not exceed 10%, and the maximum deviation of the leakage magnetic field of the magnets respectively induced by the two Hall elements can not exceed 20%. Furthermore, in this embodiment, the number of stages p of the permanent magnet 622 is 14 poles.

It can be understood that, in this embodiment, the permanent magnet 622 is integrally injection-molded into a ring structure. On the one hand, it can be formed by mold injection to save costs, and on the other hand, it can also ensure the sine degree of the magnetic field after magnetization. And, reducing the variation of the magnetic field strength, thereby improving the detection accuracy of the motor angle, and further improving the control accuracy of the pan / tilt head 100. In other embodiments, the permanent magnet 622 may also be composed of multiple magnets, and the multiple magnets may be evenly distributed on a surface of the housing 6202 facing the iron core 612 in a circumferential direction.

It can also be understood that, in this embodiment, the number of poles of the permanent magnet 622 is 14 poles, so as to form a 12-tooth-to-14-pole structure with the 12 tooth portions 6120 of the iron core 612 to reduce Cogging torque increases the torque of the motor. In practical applications, structures such as 9-tooth with 8-pole or 9-tooth with 10-pole can also be used. They are not enumerated in this embodiment.

The rotating shaft 624 is an optical axis. One end of the rotating shaft 624 is fixedly installed in the shaft hole 6200 of the upper cover 6201, and the other end of the rotating shaft 624 extends into the cylinder 6102 and is sleeved on the bearing 616. Wherein, one end of the rotation shaft 624 sleeved with the bearing 616 (that is, one end of the rotation shaft 624 installed in the cylinder 6102) is provided with a pre-pressure hole 6240, and the pre-pressure hole 6240 may be specifically Screw holes or through holes with a certain depth. In some embodiments, in order to ensure the pre-compression effect, the depth of the pre-compression hole 6240 is at least 1.5 mm, and the inner diameter is at least 1 mm.

It can be understood that, in this embodiment, one end of the bearing 616 sleeved with the rotation shaft 624 is provided with a pre-pressure hole 6240, so as to facilitate pre-pressing the bearing 616 and reduce the inside of the bearing 616. The clearance reduces the vibration and noise of the motor, thereby improving the stability of the PTZ 100. In other embodiments, the pre-pressing hole 6240 may also be omitted.

Furthermore, it can also be understood that, in this embodiment, setting the rotation shaft 624 as an optical axis is to enable forward assembly of the third motor 60 (that is, the third motor is being assembled). At 60 o'clock, the rotating shaft 624 is first fastened to the casing 620 to form the rotor 62, and then the rotor 62 is mounted to the stator 61) to reduce assembly errors, (i.e. The abutting portion of the casing 620 can abut against a bearing 616 located at the top of the bearing cavity 6100, reducing the gap between the upper cover 6201 of the casing 620 and the stator 61), so that the first The structure of the three-motor 60 is more compact, which is conducive to achieving a miniaturized design. Further, since the gap between the upper cover 6201 of the casing 620 and the stator 61 is reduced, the permanent magnet 622 and the first linear Hall element 63 and the second linear Hall element 64 The distance between them can be shorter, which is conducive to improving the detection accuracy of the first linear Hall element 63 and the second linear Hall element 64.

In other embodiments, for example, in the first motor 20 or the second motor 40, in order to improve its load capacity, the rotation shaft 624 may also be a “T-shaped” shaft, that is, the rotation An end of the shaft 624 connected to the bearing 616 is provided with a blocking portion. Therefore, when assembling the first motor 20 or the second motor 40, reverse assembly is required, that is, first, the rotating shaft 624 and the stator 61 are connected (specifically, the rotating shaft 624 is not provided). One end of the blocking portion passes through the bearing cavity 6100 from the bottom of the bearing cavity 6100 until the blocking portion abuts against a bearing 616 located at the bottom of the bearing cavity 6100), and then the housing 620 and The rotating shaft 624 is fastened and connected. Among them, since one end of the rotating shaft 624 is in contact with the bearing 616, in order to prevent both ends of the rotating shaft 624 from being caught, the upper cover 6201 needs to be in contact with a bearing located on the top of the bearing cavity 6100. There is a certain gap between them.

The first linear Hall element 63 and the second linear Hall element 64 are mounted on a surface of the ESC 618 facing the iron core 612 (or the rotor 62) for detecting the The intensity of the leakage magnetic field of the permanent magnet 622 determines the angle of the third motor 60 (ie, the position of the rotor 62).

Wherein, in this embodiment, in order to enable the detection accuracy of the first linear Hall element 63 and the second linear Hall element 64 to meet the control accuracy requirement of the pan / tilt head 100, as shown in FIG. 7, On the plane where the first linear Hall element 63 and the second linear Hall element 64 are located, the magnetomotive force axis Fa of the first phase winding of the first linear Hall element 63 and the stator 61 of the stator 61 The mechanical angle α satisfies the formula: -30 ° ≦ 360 ° -α × p-90 ° ≦ 30 °, and the magnetomotive force axis Fb of the second linear Hall element 64 and the second phase winding of the stator 61 The mechanical angle β satisfies the formula: -30 ° ≦ 360 ° -β × p-90 ° ≦ 30 °, where p is the number of pole pairs of the permanent magnet 622 of the rotor 62. For example, in the present embodiment, the third motor 60 has a 12-tooth 14-pole structure, and the number of stages of the permanent magnet 622 is 14, then, p = 14/2 = 7, so that the mechanical angle α 2. The mechanical angle β should satisfy: 34.3 ≦ α ≦ 42.8, and 34.3 ≦ β ≦ 42.8.

Specifically, in this embodiment, the angle relationship between the first linear Hall element 63 and the magnetomotive force axis of the first phase winding is taken as an example to describe the above angle relationship.

Please refer to FIG. 8, which is a schematic diagram of an angular relationship between the first linear Hall element 63 and the magnetomotive force axis Fa of the first phase winding, where Hall A indicates a position where the first linear Hall element 63 is located. ; Fa represents the position of the magnetomotive force axis of the first phase winding under a mechanical angle; Fa ′ represents the position of the magnetomotive force axis of the first phase winding under an electrical angle; Ea represents the first phase winding The maximum value of the corresponding induced electromotive force and its location is 90 ° from Fa '. Assume that the mechanical angle between Hall A and Fa is α; then, the electrical angle between Hall A and Fa ′ α ′ = α × p, where p is the number of pole pairs of the permanent magnet 622 of the third motor 60 Further, the electrical angle θ1 between Hall A and Ea = 360 ° -α′-90 ° = 360 ° -α × p-90 °. According to the Hall induction principle of the motor, it can be known that the amplitude Ea ′ = Eacosθ1 sensed by the first linear Hall element 63. Therefore, the smaller θ1 is, the larger the amplitude sensed by the first linear Hall element 63 is, and the higher the control accuracy of the pan / tilt head 100 is. When the first linear Hall element 63 is located exactly at the position where the maximum value of the induced electromotive force corresponding to the first phase winding is located (that is, when the electrical angle θ1 = 0 between Hall A and Ea), the The amplitude sensed by the first linear Hall element 63 can reach a maximum value. In addition, according to experimental tests, it can be known that when -30 ° ≤θ1≤30 °, the amplitude value sensed by the first linear Hall element 63 can reach an absolute error of ± 0.05 °, which can satisfy the PTZ 100 Control accuracy requirements.

Similarly, it can be obtained that when the second linear Hall element 64 and the position of the maximum value of the induced electromotive force corresponding to the second-phase winding are located, the electrical angle θ2 = 360 ° -β × p-90 ° also satisfies -30. When ° ≦ θ2 ≦ 30 °, the amplitude sensed by the second linear Hall element 64 can also meet the control accuracy requirement of the pan / tilt head 100.

Therefore, in the embodiment of the present application, the installation position of the first linear Hall element 63 is determined according to the magnetomotive force axis of the first phase winding of the third motor 60, so that the first linear Hall element 63 63 is as close as possible to the position where the maximum value of the induced electromotive force corresponding to the first phase winding is located, and the second linear Hall element 64 is determined according to the magnetomotive force axis of the second phase winding of the third motor 60 Such that the second linear Hall element 64 is as close as possible to the position where the maximum value of the induced electromotive force corresponding to the second phase winding is located, so that the first linear Hall element 63 and the first linear Hall element 63 The amplitude sensed by the two linear Hall elements 64 is relatively large, thereby meeting the control accuracy requirements of the pan / tilt head 100.

Further, in some embodiments, in order to reduce the sensing error between the first linear Hall element 63 and the second linear Hall element 64, and further improve the position detection accuracy of the rotor 62, the The mechanical angle α and the mechanical angle β should be as close as possible. Therefore, in some embodiments, the mechanical angle α is equal to the mechanical angle β (that is, α = β). At this time, because the magnetomotive force axis of the first phase winding and the second phase winding are The mechanical angle between the magnetomotive force axes is 120 °. Therefore, the mechanical angle γ = 120 ° between the first linear Hall element 63 and the second linear Hall element 64.

Alternatively, in other embodiments, when the ideal mounting angle of the first linear Hall element 63 or the second linear Hall element 64 (that is, 360 ° -α × p-90 ° = 0, 360 ° -β × p-90 ° = 0) coincides with a certain tooth portion 6120 of the iron core 612, a sufficient height needs to be left between the iron core 612 and the ESC 618 to install the first A linear Hall element 63 or the second linear Hall element 64 is not conducive to achieving a miniaturized design. Therefore, in still other embodiments, in order to avoid interference between the first linear Hall element 63 or the second linear Hall element 64 and the teeth 6120 of the iron core 612, the first linear The mounting positions of the Hall element 63 and the second linear Hall element 64 may also be slightly offset from an ideal mounting angle, so that the first linear Hall element 63 and the second linear Hall element 64 can The tooth grooves (ie, the slots between the two tooth portions 6120) are received in the iron core 612, so that the structure of the third motor 60 is more compact. For example, in this embodiment, the mechanical angle γ between the first linear Hall element 63 and the second linear Hall element 64 may also be 123 °.

In addition, in this embodiment, in order to be able to better control the magnitude of the induced leakage magnetic field strength of the first linear Hall element 63 and the second linear Hall element 64 to meet the control requirements of the pan / tilt head 100 The height difference between the first linear Hall element 63 and the second linear Hall element 64 and the permanent magnet 622 is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.

Furthermore, in this embodiment, in order to ensure that the induced curve has a better linearity, thereby improving the control accuracy of the gimbal 100, the first linear Hall element 63 and the second linear Hall The element 64 has a sensitivity of 11 mV / mT. Of course, it can be understood that, in practical applications, other sensitivity linear Hall elements can also be selected according to actual application requirements, such as the sensitivity of the first linear Hall element 63 or the second linear Hall element 64. It can also be 23mV / mT, 45mV / mT, 90mV / mT, and so on.

It can be understood that, in this embodiment, the angle of the third motor 60 is detected only by the first linear Hall element 63 and the second linear Hall element 64 in order to reach the pan / tilt In the case of 100 control accuracy requirements, the cost is reduced. In other embodiments, in order to further improve the detection accuracy of the angle of the motor, it may also include a third Hall element, a fourth Hall element, and the like.

Further, another embodiment of the present application further provides a drone. The drone includes a fuselage and the camera module 300 provided in the above embodiments, and the vibration reduction module 80 in the camera module 300. Mounted on the body.

In general, the motor provided in the embodiments of the present application senses the angle of the motor through the first linear Hall element and the second linear Hall element, and determines the first linear Hall according to the magnetomotive force axis of the first phase winding thereof. The mounting position of the element, and determining the mounting position of the second linear Hall element according to the magnetomotive force axis of the second phase winding thereof, can enable the first linear Hall element and the second linear Hall element to sense The obtained amplitude can meet the control accuracy requirements of the gimbal. Therefore, the motor provided in the embodiment of the present application can accurately estimate the angle of the motor through only two linear Hall elements, which can reduce costs and facilitate miniaturization. design.

It should be noted that the preferred embodiments of the present application are given in the description of the present application and the accompanying drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described in the present specification. These examples are not intended as an additional limitation on the content of this application, and the examples are provided to make the understanding of the disclosure of this application more thorough and comprehensive. In addition, the above technical features continue to be combined with each other to form various embodiments not listed above, which are all regarded as the scope described in the description of this application; further, for those of ordinary skill in the art, improvements or changes can be made according to the above description. All these improvements and transformations should fall within the protection scope of the appended claims of this application.

Claims (16)

1. A motor characterized by comprising:

   stator;

   A rotor sleeved on the stator and rotatable relative to the stator about a rotation axis of the rotor;

   The first linear Hall element and the second linear Hall element are both fixedly mounted on the stator, and a plane where the first linear Hall element and the second linear Hall element are located is perpendicular to the rotation axis, and , On the plane, the mechanical angle α between the first linear Hall element and the magnetomotive force axis of the first phase winding of the stator satisfies: -30 ° ≦ 360 ° -α × p-90 ° ≤30 °, the mechanical angle β between the second linear Hall element and the magnetomotive force axis of the second phase winding of the stator satisfies: -30 ° ≤360 ° -β × p-90 ° ≤30 ° Where p is the number of pole pairs of the rotor.
2. The electric machine according to claim 1, wherein the mechanical angle α is equal to the mechanical angle β.
3. The motor according to claim 1, wherein a mechanical angle γ between the first linear Hall element and the second linear Hall element is 123 °.
4. The motor according to claim 1, wherein the sensitivity of the first linear Hall element and the second linear Hall element is 11 mV / mT.
5. The electric machine according to any one of claims 1-4, wherein the stator comprises:

   A stator base comprising a base and a cylinder connected to the base;

   An iron core sleeved on the cylinder; and,

   A coil wound around the iron core;

   The rotor is mounted on the cylinder, and the first linear Hall element and the second linear Hall element are fixedly mounted on a surface of the base facing the core.
6. The electric machine according to any one of claims 1-4, wherein the stator comprises:

   A stator base comprising a base and a cylinder connected to the base;

   An iron core sleeved on the cylinder body;

   A coil wound around the core; and,

   An electric adjustment board, which is sleeved on the cylinder and is fixedly installed on the base;

   The rotor is installed in the cylinder body, and the first linear Hall element and the second linear Hall element are fixedly installed on a surface of the ESC facing the iron core.
7. The electric machine according to claim 6, characterized in that the stator further comprises: an electric adjustment plate pressing piece, which is disposed between the iron core and the electric adjustment plate, and is used for placing the electric adjustment plate piece Fixedly mounted on the base;
8. The motor according to claim 7, characterized in that the iron core includes a plurality of teeth, and the surface of the pressing plate of the electrical adjustment plate is provided with a protrusion, and the protrusion is locked in the protrusion. Between two of the teeth.
9. The electric machine according to claim 5, wherein the rotor comprises:

   A casing including an upper cover and a casing, the casing being sleeved on the outer periphery of the iron core;

   A permanent magnet, which is disposed on a surface of the casing facing the iron core and leaves a gap with the iron core;

   One end of the rotating shaft is fixedly installed in the upper cover, and the other end is rotatably installed in the cylinder.
10. The motor according to claim 9, wherein a height difference between the first linear Hall element and the second linear Hall element and the permanent magnet is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.
11. The motor according to claim 9, wherein the permanent magnet has a ring structure and is integrally injection-molded from a magnetic material.
12. The motor according to claim 9, wherein the rotation axis is an optical axis.
13. The motor according to claim 12, wherein a pre-pressure hole is provided at one end of the rotating shaft installed in the cylinder.
14. A gimbal, comprising the motor according to any one of claims 1-13.
15. A camera module, comprising the pan / tilt head according to claim 14.
16. A drone, comprising the camera module according to claim 15.

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