Abstract:
A motor and a gimbal having the same. The motor includes a stator and a rotor, and further includes a connection shaft. The rotor is fixedly connected with the connection shaft, the connection shaft is rotatably connected with the stator through a bearing, and the connection shaft is provided in an axial direction thereof with a central through hole. The present disclosure further discloses a gimbal using the motor described above. In an embodiment, it is able to avoid the problem that a signal wire is wound and exposed outside the motor or the gimbal, solve the problem that the signal wire could be released or rewound with the positive or negative rotation of the motor, and reduce the length of the wire.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority to and the benefit of the filing date of Chinese Patent Application No. 201610079564.8, filed on Feb. 4, 2016 with the State Intellectual Property Office of China and entitled “Motor and Gimbal,” the content of which is hereby incorporated by reference in its entirety. 
       FIELD 
       [0002]    Embodiments of the present disclosure relate to the technical field of unmanned aerial vehicles, and more particularly, to a motor and a gimbal having the same. 
       BACKGROUND 
       [0003]    With the development of the unmanned aerial vehicle technology, the technology of aerial photographing with the unmanned aerial vehicle comes out, where it is necessary to use a gimbal during the aerial photographing. 
         [0004]    In general, the gimbal is a supporting platform for mounting a photographing apparatus, and photographing of an object from various angles may be achieved by adjusting the gimbal. However, as for a prior gimbal, devices, such as a motor and a camera, are generally connected with a controller by winding flexible wires outside the gimbal. However, under this wiring mode, there is a disadvantage that it is necessary to set a segment of a wire aside during winding the wire around an output shaft of the motor, such that the wire wound around the output shaft of the motor could be released or rewound with the positive or negative rotation of the motor, when the motor rotates. Therefore, the wire is scattered outside the gimbal; moreover, since there is a need to set a segment of the wire aside for cooperating with the rotation of the motor, the length of the flexible wire is increased as a whole, which affects the effect of a transmitted image. 
       SUMMARY 
       [0005]    In view of this, it is necessary to provide a motor and a gimbal having the same, so as to achieve reduction in the length of the signal wire and avoid the problem that the signal wire is wound and exposed outside the structure. 
         [0006]    An embodiment of the present disclosure provides a motor. The motor includes a stator and a rotor, and further includes a connection shaft. The rotor is fixedly connected with the connection shaft, the connection shaft is rotatably connected with the stator through a bearing, and the connection shaft is provided in an axial direction thereof with a central through hole. 
         [0007]    Preferably, the motor further includes a drive board, with the drive board electrically connected with the stator of the motor and driving the motor. 
         [0008]    Preferably, the motor further includes a magnetic encoder, with the magnetic encoder electrically connected with the drive board and configured to measure angle and/or position information of the motor and feed back the measured information to the drive board. 
         [0009]    An embodiment of the present disclosure further provides a gimbal based on the motor as described above, which includes a fixing base, a photographing apparatus, a signal wire and at least one motor as described above. The fixing base is connected with the photographing apparatus through the at least one motor. The signal wire is arranged to pass through the central through hole of the connection shaft of the at least one motor. 
         [0010]    Preferably, the motors included in the gimbal are in number of two or three, with the two or three motors connected in series, and the gimbal further includes a connecting arm connected between two adjacent ones of the motors. A guide channel is provided inside the connecting arm, and the signal wire is arranged to pass through the guide channel and the central through holes of the connection shafts of the motors. In the motors connected in series, first one is fixedly connected with the fixing base, and last one is fixedly connected with the photographing apparatus. 
         [0011]    Preferably, the axial directions of the connection shafts of the two or three motors are perpendicular to one another. 
         [0012]    Preferably, the gimbal further includes a main control board, with the main control board fixed onto any of the motors of the gimbal and configured to adjust rotation of the at least one motor based on attitude information of the photographing apparatus. 
         [0013]    Preferably, the main control board is electrically connected with the stator of the at least one motor through the signal wire; or the at least one motor each includes a drive board, and the main control board is electrically connected with the drive board of the motor through the signal wire. 
         [0014]    Preferably, the at least one motor in the gimbal uses one drive board, with the drive board fixedly connected onto any of the motors of the gimbal. 
         [0015]    Preferably, the gimbal further includes an inertial measurement unit and a main control board, the inertial measurement unit is electrically connected with the main control board and fixed onto the motor connected with the photographing apparatus, and the inertial measurement unit is configured to sense attitude information of the photographing apparatus and send the attitude information of the photographing apparatus to the main control board. 
         [0016]    An embodiment of the present disclosure further provides a gimbal, which includes at least one motor including a stator, a rotor and a connection shaft. The rotor is fixedly connected with the connection shaft, the connection shaft is rotatably connected with the stator through a bearing, and the connection shaft is provided in an axial direction thereof with a central through hole. 
         [0017]    The present disclosure has the following beneficial effects: with the motor and the gimbal based on the motor provided by the embodiments of the present disclosure, it is able to avoid the problem in the prior art that the signal wire is wound and exposed outside the motor or the gimbal, solve the problem that the signal wire could be released or rewound with the positive or negative rotation of the motor, and reduce the length of the wire. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a schematic structural view of a motor provided by an embodiment of the present disclosure; 
           [0019]      FIG. 2  is a schematic assembly diagram of a gimbal using the motor shown in  FIG. 1 ; 
           [0020]      FIG. 3  is a schematic assembly diagram of another gimbal using the motor shown in  FIG. 1 ; and 
           [0021]      FIG. 4  is a view of a control system of the gimbal shown in  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    The present disclosure will be further described below in detail in conjunction with the drawings and embodiments. It is to be understood that specific embodiments described herein are intended only to explain the present disclosure, rather than limiting the present disclosure. It is also to be noted that only parts, but not all, of the structures associated with the present disclosure are shown in the drawings for the sake of description. 
         [0023]    Referring to  FIG. 1 , a motor  100  provided by a preferred embodiment of the present disclosure includes a stator  11 , a rotor  12  and a connection shaft  13 . The stator  11  is fixed onto a casing of the motor  100 . The rotor  12  is fixedly connected with the connection shaft  13 , the connection shaft  13  is rotatably connected with the stator  11  through a bearing (not shown), and the rotor  12  drives the connection shaft  13  to rotate on the stator  11 . The connection shaft  13  is provided in an axial direction thereof with a central through hole  14 . Preferably, the motor  100  further includes a drive board  15 , the drive board  15  is electrically connected with the stator  11  of the motor  100  for driving the motor  100  to rotate. In the present embodiment, the drive board  15  is exemplarily fixed to the back of the motor  100 . In addition, the motor  100  further includes a magnetic encoder  16  electrically connected with the drive board  15 .  FIG. 1  shows an exemplary arrangement that the magnetic encoder  16  is integrated into the drive board  15 . In other implementations, the drive board  15  and the magnetic encoder  16  may also be arranged separately, with the magnetic encoder  16  connected with the drive board  15  through a signal wire. The magnetic encoder  16  is arranged to be coaxial with the connection shaft  13 , for measuring angle and/or position information of the motor  100  and feeding back the measured information to the drive board  15 . In this way, it is possible to adjust the rotation of the motor  100  based on the fed-back angle and/or position information of the motor  100 . 
         [0024]    If there is a need to connect the motor  100  to an external device through a signal wire, the signal wire may be arranged within the central through hole  14  of the connection shaft  13 . Such an arrangement makes it possible to prevent the signal wire from being wound and exposed outside the motor  100 , and also prevent the signal wire from being rotated and rewound with the rotation of the motor  100 . Therefore, it is also unnecessary to set a segment of the signal wire aside for cooperating with the rotation of the motor  100 , thereby effectively saving the material of the signal wire. 
         [0025]    Referring to  FIG. 2 , an embodiment of the present disclosure further provides a gimbal  200  using the motor described above. The gimbal  200  includes a fixing base  21 , a photographing apparatus  22 , a motor  23  and a signal wire  24 . Here, the motor  23  includes a stator  231 , a rotor  232  and a connection shaft  233 . The connection shaft  233  is provided with a central through hole  2331 . Preferably, the motor  23  further includes a drive board  234  and a magnetic encoder  235 . The structure of the motor  23  is similar to that of the motor  100  described above, which will not be described in detail herein. 
         [0026]    The fixing base  21  is configured for fixation with a frame (not shown) of an unmanned aerial vehicle, the stator  231  is fixed onto the fixing base  21 , and the rotor  232  is fixedly connected with the photographing apparatus  22 .  FIG. 2  shows an exemplary arrangement that the rotor  232  is fixedly connected with the photographing apparatus  22  by a connector  27 . Specifically, the rotor  232  is fixedly connected with one end of the connector  27 , and the photographing apparatus  22  is connected with the other end of the connector  27  opposed to the fixing base  21 . The rotor  232  drives the connector  27  to rotate, thereby driving the photographing apparatus  22  to rotate. The connector  27  is provided therein with a central through hole  271 . The signal wire  24  passes through the central through hole  2331  of the connection shaft  233  and the central through hole  271  of the connector  27 . In other embodiments, the connector  27  may also be a fastener such as a bolt, and in this case, the signal wire  24  passes through only the central through hole  2331  of the connection shaft  233 . 
         [0027]    Preferably, the gimbal  200  further includes a main control board  25  fixed onto the motor  23 , and the signal wire  24  includes a first signal wire  241  connected between the control board  25  and the photographing apparatus  22 , a second signal wire  242  connected between the control board  25  and the drive board  234 , and a third signal wire  243  connected between the photographing apparatus  22  and an image transmission module in the unmanned aerial vehicle. The first signal wire  241  is arranged to pass through the central through hole  271  of the connector  27 , for controlling a photographing mode or the like of the photographing apparatus  22 . The second signal wire  242  is arranged to pass through the central through hole  2331  of the connection shaft  233 , for supplying a drive control signal to the motor  23 . The third signal wire  243  is a high-definition signal wire and is arranged to pass through the central through hole  271  of the connector  27  and the central through hole  2331  of the connection shaft  233 , for transmitting aerial photographing data acquired by the photographing apparatus  22  to the image transmission module. 
         [0028]    The magnetic encoder  235  of the motor  23  measures angle and/or position information of the motor  23 , and feeds back the measured information to the drive board  234 . The drive board  234  sends the obtained angle and/or position information of the motor  23  to the main control board  25 . The main control board  25  may then send a drive control command for another time to the drive board  234  based on the fed-back angle and/or position information of the motor  23 , so as to drive and control the rotation of the motor  23 . 
         [0029]    The gimbal  200  further includes an inertial measurement unit  26 .  FIG. 2  shows an exemplary arrangement that the inertial measurement unit  26  is integrated into the main control board  25 , but in other implementations, the main control board  25  and the inertial measurement unit  26  may be arranged separately, as long as the inertial measurement unit  26  is electrically connected with the main control board  25 . The inertial measurement unit  26  is configured to sense attitude information of the photographing apparatus  22  and send the attitude information of the photographing apparatus  22  to the main control board  25 . The main control board  25  adjusts the rotation of the motor  23  based on the attitude information of the photographing apparatus  22 . 
         [0030]    It should be noted that the main control board  25  described above may also be replaced with a control apparatus in the unmanned aerial vehicle, that is, the control apparatus in the unmanned aerial vehicle may be used to control the rotation of the motor  23 , the photographing mode of the photographing apparatus  22 , and the like. The connection mode in this case may be in such a way that the photographing apparatus  22 , the inertial measurement unit  26  and the drive board  234  of the motor  23  are connected directly to the control apparatus in the unmanned aerial vehicle through the signal wire  24 . In addition, the motor  23  may also not be provided with the drive board  234 , and the stator  231  of the motor  23  may be electrically connected with the control apparatus in the unmanned aerial vehicle, so that the rotation of the motor  23  may be controlled directly by the control apparatus in the unmanned aerial vehicle. It will be appreciated that, in practical applications, the number of the motors  23  in the gimbal  200  may be specifically set according to the application occasions; and although one motor  23  is exemplarily arranged in  FIG. 2 , it does not limit the present disclosure. 
         [0031]    In other embodiments, in the case that the number of the motors  23  included in the gimbal  200  is more than one, two adjacent motors  23  are connected by a connecting arm. Moreover, a guide channel is provided inside the connecting arm, and the signal wire  24  is arranged to pass through the guide channel and the central through hole  2331  of the connection shaft  233  of the motor  23 . Here, in the multiple motors  23 , first one is fixedly connected with the fixing base  21 , and last one is fixedly connected with the photographing apparatus  22 . A detailed introduction will be given below by taking a case that the gimbal  200  includes three motors  23  as an example. 
         [0032]    Referring to  FIG. 3 , a gimbal  300  includes a first motor  32 , a second motor  33  and a third motor  34 . The first motor  32  is connected with the second motor  33  through a first connecting arm  41 , and the second motor  33  is connected with the third motor  34  through a second connecting arm  42 . A photographing apparatus  35  is connected onto the third motor  34 . The first motor  32  is connected with a lower side of the fixing base  31  by, for example, a fastening means or the like. An upper side of the fixing base  31  is fixed with the frame of the unmanned aerial vehicle. The first motor  32  drives the first connecting arm  41  to rotate, the second motor  33  drives the second connecting arm  42  to rotate, and the third motor  34  drives the photographing apparatus  35  to rotate. A first guide channel  411  is provided inside the first connecting arm  41 , and a second guide channel  421  is provided inside the second connecting arm  42 . Here, the first motor  32  is the first motor, and the third motor  34  is the last motor. The first motor  32  includes a first stator  321 , a first rotor  322 , a first connection shaft  323 , a first drive board  324  and a first magnetic encoder  325 , and the first connection shaft  323  is provided with a first central through hole  3231 . Each of the second motor  33  and the third motor  34  has a substantially same structure as that of the first motor  32 . Referring to  FIG. 3 , the second motor  33  includes a second stator  331 , a second rotor  332 , a second connection shaft  333 , a second drive board  334  and a second magnetic encoder  335 , and the second connection shaft  333  is provided with a second central through hole  3331 . The third motor  34  includes a third stator  341 , a third rotor  342 , a third connection shaft  343 , a third drive board  344  and a third magnetic encoder  345 , and the third connection shaft  343  is provided with a third central through hole  3431 . 
         [0033]    An embodiment of the present disclosure further provides a gimbal based on the motor as described above, which includes a fixing base, a photographing apparatus, a signal wire and at least one motor as described above. The fixing base is connected with the photographing apparatus through the at least one motor. The signal wire is arranged to pass through the central through hole of the connection shaft of the at least one motor. 
         [0034]    An embodiment of the present disclosure further provides a gimbal based on the motor as described above, which includes a fixing base, a photographing apparatus, a signal wire and at least one motor as described above. The fixing base is connected with the photographing apparatus through the at least one motor. The signal wire is arranged to pass through the central through hole of the connection shaft of the at least one motor. 
         [0035]    An embodiment of the present disclosure further provides a gimbal based on the motor as described above, which includes a fixing base, a photographing apparatus, a signal wire and at least one motor as described above. The fixing base is connected with the photographing apparatus through the at least one motor. The signal wire is arranged to pass through the central through hole of the connection shaft of the at least one motor. 
         [0036]    A main control board  37  is fixed onto the third motor  34 , and is connected with the first drive board  324 , the second drive board  334  and the third drive board  344  through the signal wire  39 , respectively. An inertial measurement unit  38  is fixed onto the third motor  34 , and is connected with the main control board  37  through the signal wire  39 . The inertial measurement unit  38  is integrated onto the main control board  37  for sensing attitude information of the photographing apparatus  35  and sending the attitude information of the photographing apparatus  35  to the main control board  37 . The photographing apparatus  35  is connected with an image transmission module of the unmanned aerial vehicle through the signal wire  39 , to transmit the aerial photographing data acquired by the photographing apparatus  35  to the image transmission module of the unmanned aerial vehicle. The signal wire  39  is arranged to pass through the first guide channel  411 , the second guide channel  421 , the first central through hole  3231  of the first connection shaft  323  of the first motor  32 , the second central through hole  3331  of the second connection shaft  333  of the second motor  33 , and the third central through hole  3431  of the third connection shaft  343  of the third motor  34 . 
         [0037]    On the basis of the embodiment described above, the first connection shaft  323  of the first motor  32  is set as a yaw axis, the second connection shaft  333  of the second motor  33  is set as a rolling axis, and the third connection shaft  343  of the third motor  34  is set as a pitching axis. In this implementation, the first motor  32  rotates around the yaw axis in a range of +340° to −340°, the second motor  33  rotates around the rolling axis in a range of +40° to −220°, and the third motor  34  rotates around the pitching axis in a range of +45° to −135°. The yaw, rolling and pitching axes are three axes perpendicular to one another. The embodiment of the present disclosure may enable the photographing apparatus  35  to be adjusted on the photographing angle and/or position in three degrees of freedom. It should be noted that, in other implementations, it may also be arranged that the first motor  32  rotates around the yaw axis in a range of +360° to −360°, the second motor  33  rotates around the rolling axis in a range of +360° to −360°, and the third motor  34  rotates around the pitching axis in a range of +360° to −360°, where the embodiments of the present disclosure are not limited to the ranges of rotation described above. 
         [0038]    In the present disclosure, it is possible to prevent the signal wire  39  from being exposed outside the gimbal  300 , by arranging the signal wire  39  to pass through the first central through hole  3231  of the first connection shaft  323  of the first motor  32 , the second central through hole  3331  of the second connection shaft  333  of the second motor  33 , the third central through hole  3431  of the third connection shaft  343  of the third motor  34 , the first guide channel  411  of the first connecting arm  41 , and the second guide channel  421  of the second connecting arm  42 . In addition, since the signal wire  39  is arranged in each of the guide channels (the first guide channel  411  and the second guide channel  421 ) and each of the central through holes (the first central through hole  3231 , the second central through hole  3331  and the third central through hole  3431 ), the signal line  39  would not be wound with the rotations of the motors, and there is no need to set a segment of the signal wire  39  aside for cooperating with the rotations of the motors, thereby effectively saving the material of the signal wire  39 . 
         [0039]    In  FIG. 3 , the main control board  37  is exemplarily arranged on the third motor  34 , which does not limit the present disclosure. In other implementations, the main control board  37  may be arranged on any one of the motors of the gimbal  300 , for example, it may be arranged on the first motor  32 . Here, the photographing apparatus  35  may be a camera, a video camera or the like. 
         [0040]    It should be noted that, in the case that the motor of the gimbal  300  does not include a drive board, the main control board  37  may be electrically connected with the stator of the motor through the signal wire  39 . In addition, all the motors in the gimbal  300  provided by the embodiment of the present disclosure may share one drive board, in this case, the drive board may be fixedly connected onto any one of the motors in the gimbal  300 . In other words, only one motor in the gimbal  300  is provided with a drive board which drives all the motors in the gimbal  300  to rotate. 
         [0041]    It should be noted that the signal wire  39  described above includes a high-definition data signal wire, a control signal wire and a feedback signal wire. The high-definition data signal wire transmits the aerial photographing data acquired by the photographing apparatus  35 . The control signal wire is configured to transmit a drive control signal for each motor, a photographing mode control signal for the photographing apparatus  35  and the like. The feedback signal wire is configured to transmit the attitude information of the photographing apparatus  35 , the angle and/or position information of each motor and the like. 
         [0042]    Referring to  FIG. 4 , a control system  400  includes an image transmission module  40 , a first motor  32 , a second motor  33 , a third motor  34 , a main control board  37  and a photographing apparatus  35 . Here, through a high-definition data signal wire, the photographing apparatus  35  is connected with the image transmission module  40  of the unmanned aerial vehicle, and electrically connected with the main control board  37 . The first drive board  324 , the second drive board  334  and the third drive board  344  each are connected with the main control board  37  through a feedback signal wire. The inertial measurement unit  38  is connected with the main control board  37  through a feedback signal wire. When the photographing apparatus  35  is moved, the inertial measurement unit  38  senses the attitude of the photographing apparatus  35  and transmits it to the main control board  37  through the feedback signal wire. The main control board  37  generates control commands based on the received attitude information of the photographing apparatus  35 , and sends the control commands to the first drive board  324 , the second drive board  334  and the third drive board  344  through control signal wires, respectively. The first drive board  324 , the second drive board  334  and the third drive board  344  drive, based on their corresponding control commands, their respective motors (the first motor  32 , the second motor  33  and the third motor  34 ) to rotate, respectively. In addition, the first magnetic encoder  325 , the second magnetic encoder  335  and the third magnetic encoder  345  measure the angle and/or position information of their respective motors, and then send the measured information to the main control board  37  via the first drive board  324 , the second drive board  334  and the three drive board  344  through the feedback signal wires, respectively. The main control board  37  sends control commands for another time to the first drive board  324 , the second drive board  334  and the third drive board  344 , based on the received angle and/or position information of the individual motors, so as to adjust the rotations of the individual motors, thereby finally achieving precise control of the angle and position of the photographing apparatus  35  in the photographing operation. 
         [0043]    As described above, in the embodiments of the present disclosure, the connection shaft of the motor is provided with a central through hole, which enables the signal wire to be arranged to directly pass through the inside of the motor, thereby effectively preventing the signal wire from being wound outside the motor. Meanwhile, by arranging the signal wire (including the high-definition data signal wire, the control signal wire and the feedback signal wire) to pass through the individual motors and guide channels, the wire is shortened, effectively saving the material of the signal wire. In addition, since the longer the length of the high-definition data signal wire connected between the photographing apparatus and the unmanned aerial vehicle, the greater the attenuation of the image transmission signal, the shortened wire also improves the effect of images transmitted though the high-definition data signal wire. 
         [0044]    It is to be noted that the foregoing is merely illustrative of preferred embodiments of the present disclosure and the technical principle applied thereto. It will be understood by those skilled in the art that the present disclosure is not limited to the particular embodiments described herein. And it would be apparent to those skilled in the art that various obvious modifications, rearrangements and substitutions can be made without departing from the scope of protection of the present disclosure. Thus, although the present disclosure has been described in detail with reference to the above embodiments, the present disclosure is not limited to the above embodiments, and may also encompass other further equivalent embodiments without departing from the concept of the present disclosure. The scope of the present disclosure is to be determined by the scope of the appended claims.