Patent Description:
A motor is a device that implements conversion between electric energy and mechanical energy. It can provide power for various devices by using a driving torque that is generated. Among devices using a motor, a gimbal can use motor rotation to complete fastening of a shooting device mounted to it, arbitrarily adjust a posture of the shooting device (for example, change a height and/or a direction of the shooting device) and stably keep the shooting device in a definite posture, thereby achieving stability and smoothness of the shooting device, and implementing multi-angle shooting.

In the existing motor, a rotation shaft of the motor is generally connected to an external member, to drive the external member to rotate. By connecting the rotation shaft with the external member, the motor transmits a torque force generated on the rotation shaft to the external member, so that the stable movement of the external member is affected.

The German patent application <CIT> discloses a disc drive with a brushless drive motor.

The Chinese patent application <CIT> discloses a motor, where the motor comprises a stator, a rotor which is connected with the stator in a rotating mode, and an electric connection device used for supplying electrical signals to the motor.

The French patent application <CIT> discloses a relatively large piloted aircraft which controls several smaller pilotless aircrafts.

The<CIT> discloses a multi-pole permanent magnet electric motor for shallow water and a shallow water type submersible pump using the motor.

The Chinese patent <CIT> discloses a gimbal, where the gimbal includes at least one shaft mechanism, shaft mechanism includes: and a support.

A main objective of preferable embodiments of the present invention is to provide a motor, to reduce a torque force transmitted by the motor to an external member.

A preferable embodiment of the present invention discloses a motor for a gimbal comprising: a rotation shaft comprising a first end portion, a second end portion and a middle portion connecting said first end portion to said second end portion, a rotor assembly configured to drive an external member to rotate, a stator assembly and a stator bearing comprises a second bearing and a third bearing, wherein a stator, being part of said stator assembly, is positioned inside of the rotor and surrounds the rotation shaft, wherein the stator is located between the second bearing and the third bearing, such that the second bearing and the third bearing are disposed on two ends of the stator, wherein the stator bearing and the rotor assembly are disposed on the middle portion of the rotation shaft, said motor further comprises a first bearing, a base connected to the first bearing of the rotation shaft, wherein the rotor assembly comprises a rotor and an external member like a second support arm of a gimbal, wherein said first bearing is connected to the first end portion of the rotation shaft and the base, wherein the stator bearing, the rotor assembly and the first bearing are sequentially arranged along in axial direction of the rotation shaft, wherein the stator assembly being connected to the rotation shaft by said stator bearing , wherein the rotor is fixedly connected to the rotation shaft at a position between said first bearing and said second bearing, wherein the stator assembly comprises a stator and an end cap.

Preferably, the rotation shaft is enclosed in a cavity formed by the base, the stator assembly and the rotor assembly.

Preferably, the motor further includes a sensor assembly configured to detect a rotation angle of the rotation shaft, the sensor assembly including a sensing driver PCB board, a sensing magnet and a sensing magnetic base for mounting the sensing magnet, the sensing magnetic base being fastened to the second end portion of the rotation shaft, and the sensing driver PCB board and the sensing magnet being disposed between the second end portion and the end cap, where the sensing driver PCB board is fastened to the end cap.

Preferably, the motor further includes a flexible circuit board connected to an external control board along the axial direction of the rotation shaft, the stator having a first surface facing the rotor assembly, the flexible circuit board being located on the first surface of the stator.

Another preferable embodiment of the present invention further discloses a gimbal, including the motor described above. Preferably, the external member being fixedly connected to the second support arm; the second support arm and the rotor being an integrated structure, or the second support arm being fastened to the rotor. Preferably, the second support arm has a connecting arm portion and a first support arm portion and a second support arm portion, where the first support arm portion and the second support arm portion are disposed at two ends of the connecting arm portion, where the first support arm portion, the connecting arm portion and the second support arm portion form a U-shaped structure;.

Preferably, the gimbal further includes a shock absorption assembly, a quick detaching assembly, a Z-axis motor and a first support arm;.

Preferably, the gimbal further includes a P-axis motor, wherein the P-axis motor is mounted on a free end portion of at least one of the first support arm portion and the second support arm portion of the second support arm;
where the first support arm is perpendicular to the second support arm. A preferable embodiment of the present invention further discloses an aircraft, including the gimbal described above, where the gimbal comprises a motor; and further having a body, where the body includes a driving device and a shooting device, wherein the shooting device is disposed on the gimbal, the gimbal is disposed on the bottom of the body and the driving device is configured to drive the motor to rotate to enable the shooting device to shoot.

According to the motor disclosed in the preferable embodiments of the present invention, a rotor assembly drives an external member to rotate, that is, the rotor assembly is connected to the external member, and the rotor assembly is connected to a non-end portion position of a rotation shaft. Therefore, compared with the prior art in which the external member is connected to an end portion position of the rotation shaft, and a torque force based on an end portion of the rotation shaft is greater than a torque force on a non-end portion of the rotation shaft, the present invention can reduce a torque force that is generated by a rotation shaft and that is transmitted to an external member, thereby improving movement stability of the external member, and additionally reduce a time loss of movement on the rotation shaft, thereby increasing a speed at
which the external member responds to motor movement.

Reference numerals: <NUM>-rotation shaft; <NUM>-rotor; <NUM>-second axial support arm; <NUM>-base; <NUM>-quick detaching assembly; <NUM>-Z-axis motor; <NUM>-P-axis motor; <NUM>-first axial support arm; <NUM>-sensing driver PCB board; <NUM>-sensing magnet; <NUM>-sensing magnetic base; <NUM>-flexible circuit board; <NUM>-end cap; <NUM>-stator; <NUM>-second bearing; <NUM>-first bearing; <NUM>-third bearing; <NUM>-shock absorption assembly.

To make the objectives, technical solutions, and advantages of the present invention clearer and more comprehensible, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that specific embodiments described herein are merely used for describing the present invention, and are not intended to limit the present invention, and technical features described below may be combined with each other as long the technical features are not mutually contradictory.

The present invention discloses a motor, a gimbal to which the motor is applied and an aircraft to which the gimbal is applied. To describe advantages of the motor in more detail, the motor is applied to the gimbal to provide descriptions. Certainly, the motor may alternatively be applied to another device.

In a preferable embodiment of the present invention, the gimbal may be a uniaxial gimbal, a biaxial gimbal or a triaxial gimbal. As shown in <FIG>, the gimbal is a triaxial gimbal, and includes a shock absorption assembly <NUM>, a quick detaching assembly <NUM>, a Z-axis motor <NUM>, a first axial support arm <NUM>, a motor that is in another preferable embodiment of the present invention and a P-axis motor <NUM>. When the gimbal is mounted on a carrying device such as an aerial photography aircraft, the shock absorption assembly <NUM> is rigidly connected to the aerial photography aircraft, to reduce vibration transmitted by the aerial photography aircraft to the gimbal. The shock absorption assembly <NUM> is detachably connected to the Z-axis motor <NUM> by using the quick detaching assembly <NUM>, and the shock absorption assembly <NUM>, the quick detaching assembly <NUM> and the Z-axis motor <NUM> are sequentially arranged along an axial direction of the Z-axis motor <NUM>. The shape of the first axial support arm <NUM> is similar to the "L" shape. The P-axis motor <NUM> is fastened to a rotor assembly of a motor in another preferable embodiment of the present invention, and may rotate with the motor in the another preferable embodiment of the present invention, to drive a load such as a camera or a searchlight.

In another embodiment, when the gimbal is a uniaxial gimbal, it includes a shock absorption assembly <NUM>, a quick detaching assembly <NUM> and a motor that is in another preferable embodiment of the present invention. When the gimbal is mounted on a carrying device such as an aerial photography aircraft, the shock absorption assembly <NUM> is rigidly connected to the aerial photography aircraft, to reduce vibration transmitted by the aerial photography aircraft to the gimbal. The shock absorption assembly <NUM> is detachably connected to the motor in the another preferable embodiment of the present invention by using the quick detaching assembly <NUM>. The shock absorption assembly <NUM>, the quick detaching assembly <NUM> and the motor in the another preferable embodiment of the present invention are sequentially arranged along an axial direction of the motor in the another preferable embodiment of the present invention. A load such as a camera or a searchlight is connected to a rotor assembly of the motor in the another preferable embodiment of the present invention. When the gimbal is a biaxial gimbal, it includes a shock absorption assembly <NUM>, a quick detaching assembly <NUM>, a Z-axis motor <NUM>, a first axial support arm <NUM> and a motor that is in another preferable embodiment of the present invention. When the gimbal is mounted on a carrying device such as an aerial photography aircraft, the shock absorption assembly <NUM> is rigidly connected to the aerial photography aircraft, to reduce vibration transmitted by the aerial photography aircraft to the gimbal. The shock absorption assembly <NUM> is detachably connected to the Z-axis motor <NUM> by using the quick detaching assembly <NUM>, and the shock absorption assembly <NUM>, the quick detaching assembly <NUM> and the Z-axis motor <NUM> are sequentially arranged along an axial direction of the Z-axis motor <NUM>. The shape of the first axial support arm <NUM> is similar to the "L" shape. One end of the first axial support arm <NUM> is connected to an output shaft of the Z-axis motor <NUM>. The motor in the another preferable embodiment of the present invention is fastened to the other end of the first axial support arm <NUM>, and may rotate with the first axial support arm <NUM>. A load such as a camera or a searchlight is carried on a rotor assembly of the motor in the another preferable embodiment of the present invention.

The P-axis motor <NUM> or the load such as the camera or the searchlight is carried on the rotor assembly of the motor in the another preferable embodiment of the present invention, that is, a rotor assembly is connected to the P-axis motor <NUM> or the load such as the camera or the searchlight. Compared with the prior art in which the load such as the camera or the searchlight is connected to an end portion position of the rotation shaft, and a torque force based on an end portion of the rotation shaft is greater than a torque force on the rotor assembly, the present invention can reduce a torque force that is generated by a rotation shaft of a motor and that is transmitted to a load such as a camera or a searchlight, thereby improving movement stability of the load such as the camera or the searchlight, and additionally reduce a time loss of movement on the rotation shaft, thereby increasing a speed at which the load such as the camera or the searchlight responds to motor movement.

When the vibration generated from the aerial photography aircraft does not need to be reduced, the shock absorption assembly <NUM> may not be disposed on the gimbal in any of the foregoing embodiments. In this case, the quick detaching assembly <NUM> is directly connected to the aerial photography aircraft.

When the gimbal does not need to be quickly detached from a carrying device such as the aerial photography aircraft, the gimbal in any of the foregoing embodiments may not include the quick detaching assembly <NUM>. In this case, the Z-axis motor <NUM> in the foregoing triaxial gimbal and biaxial gimbal embodiments is directly connected to the aerial photography aircraft, and the motor in the another preferable embodiment of the present invention in the foregoing uniaxial gimbal embodiment is directly connected to the aerial photography aircraft.

Referring to <FIG>, the motor in the another preferable embodiment of the present invention includes a base <NUM>, a rotation shaft <NUM>, a stator assembly, a first bearing <NUM>, a stator bearing and a rotor assembly that is used for driving an external member to rotate. In the foregoing triaxial gimbal embodiment, the external member refers to the P-axis motor <NUM>. In the foregoing uniaxial or biaxial gimbal embodiment, the external member refers to the load such as the camera or the searchlight. The rotation shaft <NUM> has a first end portion, a second end portion and a middle portion that connects the first end portion and the second end portion, and the base <NUM> is connected to the first end portion of the rotation shaft <NUM> by using the first bearing <NUM>. The stator bearing and the rotor assembly are disposed on the middle portion of the rotation shaft <NUM>, that is, the stator bearing and the rotor assembly are disposed on a non-end portion position of the rotation shaft <NUM>. The stator bearing, the rotor assembly and the first bearing <NUM> are sequentially arranged along an axial direction of the rotation shaft <NUM>, and the stator assembly is connected to the rotation shaft <NUM> by using the stator bearing. The rotor assembly drives the external member (the P-axis motor <NUM> in the triaxial gimbal embodiment, or the load such as the camera or the searchlight in the uniaxial or biaxial gimbal embodiment) to rotate, that is, the rotor assembly is connected to the external member and the rotor assembly is connected to the non-end portion position of the rotation shaft <NUM>. Therefore, compared with the prior art in which the external member is connected to an end portion position of the rotation shaft, and a torque force based on an end portion of the rotation shaft is greater than a torque force on a non-end portion of the rotation shaft <NUM>, the present invention can reduce a torque force that is generated by a rotation shaft <NUM> and that is transmitted to an external member (the P-axis motor <NUM> in the triaxial gimbal embodiment, or the load such as the camera or the searchlight in the uniaxial or biaxial gimbal embodiment), thereby improving movement stability of the external member (the P-axis motor <NUM> in the triaxial gimbal embodiment, or the load such as the camera or the searchlight in the uniaxial or biaxial gimbal embodiment), and additionally reduce a time loss of movement on the rotation shaft <NUM>, thereby increasing a speed at which the external member (the P-axis motor <NUM> in the triaxial gimbal embodiment, or the load such as the camera or the searchlight in the uniaxial or biaxial gimbal embodiment) responds to motor movement.

To simplify a structure of the gimbal in the embodiments of the present invention, in the foregoing triaxial or biaxial gimbal embodiment, the base <NUM> in the foregoing motor embodiment is a part of the first axial support arm <NUM>, that is, the base <NUM> is one of free ends of the first axial support arm <NUM>, that is, the base <NUM> and the first axial support arm <NUM> are an integrated structure; or the base <NUM> is fixedly connected to the first axial support arm <NUM>.

The external member is directly connected to the rotor assembly, and the rotation shaft <NUM> of the motor in the present invention does not need to extend out of the motor to connect to the external member. Therefore, in a preferable embodiment of the present invention, the rotation shaft <NUM> is enclosed in a cavity formed by the base <NUM>, the stator assembly and the rotor assembly. Such a design can prevent a micro-particle such as dust from entering the inside of the motor through the rotation shaft <NUM> and affecting performance and a service life of the motor, and can improve safety performance of the motor in the present invention.

To improve output rigidity of the motor in the present invention, and improve stability, a stator assembly in an preferable embodiment of the present invention includes a stator <NUM> and an end cap <NUM> fastened to the stator <NUM>. A stator bearing includes a second bearing <NUM> and a third bearing <NUM>. The stator <NUM> is located between the second bearing <NUM> and the third bearing <NUM>, that is, the second bearing <NUM> and the third bearing <NUM> are respectively disposed at two ends of the stator <NUM>. The second bearing <NUM> is disposed close to the rotor assembly, and the third bearing <NUM> is disposed close to the second end portion of the rotation shaft <NUM>. In the foregoing structure, the second bearing <NUM> and the third bearing <NUM> serve as a support, and the stator <NUM> is mounted between the second bearing <NUM> and the third bearing <NUM> that serve as the support, thereby improving rigidity and stability.

The rotor assembly is connected to the non-end portion position of the rotation shaft <NUM>. Specifically, the rotor assembly is connected to a position between the first bearing <NUM> and the second bearing <NUM> in the rotation shaft <NUM>, to reduce transmission of a torque force generated by the rotation shaft <NUM> and increase a speed at which an external member connected to the rotor assembly responds to the rotation shaft <NUM>.

To precisely detect a rotation angle of the rotation shaft <NUM> in real time, so as to control a rotation speed and a position of the rotation shaft <NUM>, a motor in a preferable embodiment of the present invention further includes a sensor assembly for detecting the rotation angle of the rotation shaft. The sensor assembly includes a sensing driver PCB board <NUM>, a sensing magnet <NUM> and a sensing magnetic base <NUM> for mounting the sensing magnet <NUM>. The sensing magnetic base <NUM> is fastened to a second end portion (away from the base <NUM>) of the rotation shaft <NUM>. The sensing driver PCB board <NUM> and the sensing magnet <NUM> are disposed between the second end portion and the end cap <NUM> and the sensing driver PCB board <NUM> is fastened to the end cap <NUM> of the stator assembly.

The motor in the embodiments of the present invention further includes a flexible circuit board <NUM> connected to an external control board, and along the axial direction of the rotation shaft <NUM>, the stator <NUM> has a first surface facing the rotor assembly. The flexible circuit board <NUM> is located on the first surface of the stator <NUM>.

The rotor assembly in the embodiments of the present invention includes a rotor <NUM> and a second axial support arm <NUM>. The second axial support arm <NUM> and the rotor <NUM> are an integrated structure. Alternatively, the second axial support arm <NUM> is fastened to the rotor <NUM>. An external member is fixedly connected to the second axial support arm <NUM>, and the external member rotates with the second axial support arm <NUM>. The second axial support arm <NUM> that is originally a structure of a gimbal is disposed in such a manner that the second axial support arm <NUM> and the rotor <NUM> are an integrated structure or the second axial support arm <NUM> is fastened to the rotor <NUM>. Therefore, a motor is no longer an independent part relative to the gimbal, that is, the motor is one part included in the gimbal, so that the gimbal has a more compact structure, a smaller volume and a lighter weight, helping increase a battery life of an aerial photography aircraft that carries the gimbal.

A first end of the first axial support arm <NUM> is fixedly connected to the base <NUM>, the first axial support arm <NUM> is perpendicular to the second axial support arm <NUM> and the first axial support arm <NUM> is perpendicular to the rotation shaft <NUM>. A second end of the first axial support arm <NUM> is connected to the Z-axis motor <NUM>. The Z-axis motor <NUM> is connected to the shock absorption assembly <NUM> by using the quick detaching assembly <NUM>. The shock absorption assembly <NUM>, the quick detaching assembly <NUM> and the Z-axis motor <NUM> are sequentially connected in a direction of the first axial support arm <NUM>.

The second axial support arm <NUM> and the rotor <NUM> are an integrated structure. Specifically, the second axial support arm <NUM> has a connecting arm portion and a first support arm portion and a second support arm portion that are disposed at two ends of the connecting arm portion. A rotation shaft mounting hole for mounting the rotation shaft <NUM> is provided in the connecting arm portion. The first support arm portion and the second support arm portion are symmetrically disposed about an axis of the rotation shaft mounting hole. The first support arm portion, the connecting arm portion and the second support arm portion form a U-shaped structure. Further, the P-axis motor <NUM> is mounted on a free end portion of at least one of the first support arm portion or the second support arm portion of the second axial support arm <NUM>.

The second axial support arm <NUM> is fastened to the rotor <NUM>. Specifically, the second axial support arm <NUM> includes a connecting arm portion and a first support arm portion and a second support arm portion that are disposed at two ends of the connecting arm portion. A rotor mounting hole for mounting the rotor <NUM> is provided in the connecting arm portion. The first support arm portion and the second support arm portion are symmetrically disposed about an axis of the rotor mounting hole.

An embodiment of the present invention further provides an aircraft, which includes the gimbal described above and further has a body. The body includes a driving device and a shooting device, the shooting device being disposed on the gimbal, the gimbal being disposed on the bottom of the body, and the driving device being configured to drive the motor to rotate to enable the shooting device to shoot.

Claim 1:
A motor, comprising:
a rotation shaft (<NUM>) comprising a first end portion, a second end portion, and a middle portion connecting the first end portion to the second end portion;
a rotor assembly (<NUM>,<NUM>) configured to drive an external member to rotate,
a stator assembly (<NUM>,<NUM>) and a stator bearing (<NUM>,<NUM>) comprises a second bearing (<NUM>) and a third bearing (<NUM>),
wherein a stator (<NUM>), being part of said stator assembly (<NUM>,<NUM>), is positioned inside of the rotor (<NUM>) and surrounds the rotation shaft (<NUM>),
wherein the stator (<NUM>) is located between the second bearing (<NUM>) and the third bearing (<NUM>), such that the second bearing (<NUM>) and the third bearing (<NUM>) are disposed on two ends of the stator (<NUM>), and
wherein the stator bearing (<NUM>,<NUM>) and the rotor assembly (<NUM>,<NUM>) are disposed on the middle portion of the rotation shaft (<NUM>),
characterized in that
the motor further comprising:
a first bearing (<NUM>);
a base (<NUM>) connected to the first end portion by the first bearing (<NUM>);
wherein the rotor assembly (<NUM>,<NUM>) comprises a rotor (<NUM>) and said external member, like a second support arm (<NUM>) of a gimbal,
wherein said first bearing (<NUM>) is connected to the first end portion of the rotation shaft (<NUM>) and the base (<NUM>),
wherein the stator bearing (<NUM>,<NUM>), the rotor assembly (<NUM>,<NUM>) and the first bearing (<NUM>) are sequentially arranged along in axial direction of the rotation shaft (<NUM>),
wherein the stator assembly (<NUM>,<NUM>) being connected to the rotation shaft (<NUM>) by said stator bearing (<NUM>,<NUM>),
wherein the rotor (<NUM>) is fixedly connected to the rotation shaft (<NUM>) at a position between said first bearing (<NUM>) and said second bearing (<NUM>), and
wherein the stator assembly (<NUM>,<NUM>) comprises a stator (<NUM>) and an end cap (<NUM>).