Patent Publication Number: US-2023157426-A1

Title: Umbrella pole device, electric umbrella and telescopic device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of International Application No. PCT/CN2021/075860, filed on Feb. 7, 2021, which claims priority to Chinese Patent Application No. 202010666410.5, filed on Jul. 10, 2020. The disclosures of the above-mentioned applications are incorporated herein by reference in their entireties. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to the technical field of electric umbrellas, and in particular to an umbrella pole device, an electric umbrella and a telescopic device. 
     BACKGROUND 
     After being folded, the umbrella is of a small length, and is very convenient to carry or store, thus it is deeply loved by the majority of users. However, traditional folding umbrella usually requires both hands of the user to open or fold. When the user holds some stuff in one hand and the umbrella in another, it is not convenient to open or fold the umbrella quickly. In order to open or fold the umbrella more conveniently and quickly, electric umbrellas are invented. The electric umbrella usually includes an umbrella pole device and an umbrella rib device arranged on the umbrella pole device. When the electric umbrella is opened, the umbrella pole device needs to be extended and the umbrella rib device needs to be stretched. When the electric umbrella is folded, the umbrella pole device needs to be shortened and the umbrella rib device needs to be retracted. 
     As for the traditional electric umbrella, when the electric umbrella is in a folded state, the spring is in a compressed state. When the electric umbrella needs to be opened, the compressed spring is driven to be released by the motor, so that the spring is stretched, and the electric umbrella is opened. When the electric umbrella needs to be folded, the spring is driven to be compressed again by the motor. Although compressing and releasing the spring can realize the opening and folding of the electric umbrella, it requires a relatively high torque of the motor, thus the motor with the high torque is needed. 
     SUMMARY 
     The main objective of the present disclosure is to provide an umbrella pole device, aiming to decrease the torque requirement for the motor. 
     In order to realize the above objective, the present disclosure provides an umbrella pole device, including: an umbrella head, a middle rod, and an umbrella pole transmission assembly. 
     In an embodiment, the middle rod includes a plurality of casings, the plurality of the casings are pulled apart to form an end-to-end long rod, the casing in an innermost part of the middle rod is an inner casing, the casing in an outermost part of the middle rod is an outer casing, one end of the inner casing is connected to the umbrella head. 
     In an embodiment, the umbrella pole transmission assembly is arranged in the inner casing, the umbrella pole transmission assembly includes a first transmission tube and a second transmission tube, the first transmission tube is telescopically sleeved with the second transmission tube, one end of the first transmission tube is rotatably connected to the umbrella head, and one of the first transmission tube and the second transmission tube is a rectangular spring. 
     When the first transmission tube rotates in a first direction, the second transmission tube moves toward a direction away from the umbrella head to exert a force on the outer casing, and the plurality of casings of the middle rod are pulled apart to form the end-to-end long rod. 
     When the first transmission tube rotates in a second direction, the second transmission tube moves towards a direction close to the umbrella head to cancel the force applied on the outer casing, and the second direction is opposite to the first direction. 
     In an embodiment, the second transmission tube is a rectangular spring, and the rectangular spring is sleeved outside the first transmission tube; 
     the umbrella pole transmission assembly further includes a guiding spring portion and a first slider, the guiding spring portion is arranged at an end of the first transmission tube away from the umbrella head, the guiding spring portion is provided with a first guiding spring passage, at least part of coils of the rectangular spring are arranged in the first guiding spring passage, the first slider is slidably sleeved outside the first transmission tube, the first slider is arranged between the umbrella head and the rectangular spring, the first slider is connected to one end of the rectangular spring close to the umbrella head, and an outer wall of the first slider is cooperated with an inner wall of the inner casing to confine a rotation of the first slider. 
     In an embodiment, the umbrella pole transmission assembly further includes a threaded tube, an external transmission tube and a nut; 
     one end of the threaded tube is rotatably connected to the umbrella head; 
     the first transmission tube is slidably inserted into an end of the threaded tube away from the umbrella head, and an outer wall of the first transmission tube is cooperated with an inner wall of the threaded tube to confine a relative rotation between the first transmission tube and the threaded tube; 
     the external transmission tube is slidably sleeved outside the threaded tube, and when sliding on the threaded tube, the external transmission tube is configured to drive the first transmission tube and the guiding spring portion to slide; 
     the nut is sleeved outside the threaded tube and is screwed with the threaded tube, an outer wall of the nut is cooperated with the inner wall of the inner casing so that the nut is configured to move on the threaded tube, the nut is arranged between the umbrella head and the external transmission tube, and the nut is fixedly connected to an end of the external transmission tube close to the umbrella head; and 
     the rectangular spring and the first slider are slidably sleeved outside the external transmission tube, and the inner wall of the first slider is cooperated with the outer wall of the external transmission tube to confine the rotation of the first slider. 
     In an embodiment, the umbrella pole transmission assembly further includes a T-shaped cylindrical pin and a bushing, the T-shaped cylindrical pin is sleeved outside the first transmission tube, and an inner wall of the T-shaped cylindrical pin is cooperated with the outer wall of the first transmission tube to limit a rotation of the T-shaped cylindrical pin; 
     the guiding spring portion is sleeved outside the T-shaped cylindrical pin, and a head end of the T-shaped cylindrical pin is arranged between the guiding spring portion and the umbrella head; 
     the bushing is sleeved outside the first transmission tube, and an end of the bushing away from the umbrella head is rotatably connected to the head end of the T-shaped cylindrical pin; and 
     an end of the external transmission tube away from the umbrella head is sleeved outside the bushing. 
     In an embodiment, the umbrella pole transmission assembly further includes a first reinforcing tube, the first reinforcing tube is sleeved outside the rectangular spring, and is relatively fixed to the rectangular spring, and one end of the first reinforcing tube close to the umbrella head is connected to the first slider. 
     In an embodiment, the first transmission tube is a rectangular spring, and the second transmission tube is sleeved outside the rectangular spring; 
     the umbrella pole transmission assembly further includes a second slider, the second slider is sleeved outside the rectangular spring, the second slider is arranged between the umbrella head and the second transmission tube, and is fixedly connected to an end of the second transmission tube close to the umbrella head; 
     an inner wall of the second slider is provided with a second guiding spring passage, at least part of the coils of the rectangular spring are arranged in the second guiding spring passage, and an outer wall of the second slider is cooperated with the inner wall of the inner casing so that the second slider is configured to move on the rectangular spring. 
     In an embodiment, the umbrella pole transmission assembly further includes a second reinforcement tube, the rectangular spring is sleeved outside the second reinforcement tube and is relatively fixed to the second reinforcement tube, and an end of the second reinforcing tube close to the umbrella head is rotatably connected to the umbrella head. 
     In an embodiment, the first transmission tube is a rectangular spring, and the rectangular spring is sleeved outside the second transmission tube; 
     the umbrella pole transmission assembly further includes a third slider and an anti-rotation block; 
     the rectangular spring is sleeved outside the third slider, the third slider is fixedly connected to the end of the second transmission tube close to the umbrella head, an outer wall of the third slider is provided with a third guiding spring passage, at least part of the coils of the rectangular spring are arranged in the third guiding spring passage; 
     the anti-rotation block is arranged on an end of the inner casing away from the umbrella head, the second transmission tube is slidably inserted on the anti-rotation block, and an inner wall of the anti-rotation block is cooperated with the outer wall of the second transmission tube so that the third slider is configured to move on the rectangular spring. 
     In an embodiment, the umbrella pole transmission assembly further includes a third reinforcing tube, and the third reinforcing tube is sleeved outside the rectangular spring and is relatively fixed to the rectangular spring. 
     In an embodiment, the umbrella pole device further includes a driving assembly arranged in the umbrella head, the driving assembly includes a motor, a main gear, a slave gear and a gearbox, the main gear is arranged on an output shaft of the motor, the slave gear is arranged at one end of the first transmission tube close to the umbrella head, and a speed change gear of the gearbox is respectively engaged with the main gear and the slave gear. 
     In an embodiment, the umbrella pole device further includes an upper nest, a lower nest and an umbrella rib transmission assembly; 
     the upper nest is arranged at the end of the outer casing away from the umbrella head and is configured to be pushed by the second transmission tube; 
     the lower nest is slidably arranged on the outer casing, and the lower nest is arranged between the umbrella head and the upper nest; 
     the umbrella rib transmission assembly includes at least one upper pulley, at least one lower pulley, and a stay rope, the upper pulley is arranged on the upper nest, the lower pulley is arranged on the lower nest, one end of the stay rope is fixed to the umbrella head, another end passes through an innermost tube of the umbrella pole transmission assembly to alternately bypasses the upper pulley and the lower pulley, and is fixed on the upper nest or the lower nest. 
     The present disclosure also provides an electric umbrella, including: 
     the umbrella pole device; and 
     an umbrella rib device including an umbrella rib and an umbrella cloth arranged on the umbrella rib; 
     the umbrella rib includes a first rib, a second rib, a tension spring and a third rib, one end of the first rib is connected to the upper nest, one end of the second rib is connected to the lower nest, another end of the second rib is slidably connected to the first rib, two ends of the tension spring are respectively connected to the first rib and the second rib, and the third rib is connected to another end of the first rib. 
     The present disclosure also provides a telescopic device, including: 
     a mounting seat, the mounting seat is the umbrella head; 
     a casing assembly, the casing assembly is the middle rod; and 
     an inner transmission assembly, the inner transmission assembly is the umbrella pole transmission assembly. 
     In an embodiment, the telescopic device is applied to a selfie stick, a clothes rail or a robot, and an end of the outer casing away from the mounting seat is provided with a clamp positioning member; 
     when the telescopic device is applied to the selfie stick, the clamp positioning member is configured to fix a mobile phone or a camera; 
     when the telescopic device is applied to the clothes rail, the clamp positioning member is a fork; and 
     when the telescopic device is applied to the robot, the clamp positioning member is a manipulator. 
     In the umbrella pole transmission assembly and the telescopic device, one end of the first transmission tube is rotatably connected to the umbrella head (mounting seat), the first transmission tube is telescopically sleeved with the second transmission tube. When the first transmission tube rotates, the second transmission tube can move towards the end away from the umbrella head (mounting seat), and can apply a force to the outer casing, so that multiple casings of the middle rod (casing assembly) are pulled apart to form an end-to-end long rod. In this way, the compression of the first transmission tube and the second transmission tube can be avoided, that is, the compression of the rectangular spring can be avoided. Therefore, when the first transmission tube is connected to the driving assembly, and the first transmission tube is driven to rotate by the driving assembly, the torque requirement for the driving assembly is relatively low. A driving assembly with a small torque can be used to drive the first transmission tube to rotate, and the driving assembly with a small torque is usually smaller in size, which can reduce the size of the umbrella head (mounting seat), and miniaturize the electric umbrella (telescopic device). In the actual manufacturing, under a premise of achieving the same effect, the price of the rectangular spring is far lower than that of the threaded rod. Using the rectangular spring as the transmission tube can reduce the production cost of the electric umbrella (telescopic device). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to illustrate the technical solutions in the embodiments of the present disclosure or in the related art more clearly, the following briefly introduces the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only part of embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without any creative effort. 
         FIG.  1    is a schematic structural view of an electric umbrella according to an embodiment of the present disclosure. 
         FIG.  2    is a schematic structural view of an umbrella pole device of the electric umbrella in  FIG.  1   . 
         FIG.  3    is a three-dimensional exploded view of an umbrella pole device of an electric umbrella according to an embodiment of the present disclosure. 
         FIG.  4    is a sectional view of an umbrella pole device of the electric umbrella in  FIG.  3   . 
         FIG.  5    is a partial enlarged view at A in  FIG.  4   . 
         FIG.  6    is a partial enlarged view at B in  FIG.  4   . 
         FIG.  7    is a three-dimensional structural schematic view of the umbrella pole device of the electric umbrella in  FIG.  3    in a pulled state. 
         FIG.  8    is a sectional view of  FIG.  7   . 
         FIG.  9    is a three-dimensional exploded view of an umbrella pole device of an electric umbrella according to an embodiment of the present disclosure. 
         FIG.  10    is a sectional view of the umbrella pole device of the electric umbrella in  FIG.  9   . 
         FIG.  11    is a partial enlarged view at C in  FIG.  10   . 
         FIG.  12    is a partial enlarged view at D in  FIG.  10   . 
         FIG.  13    is a sectional view of an umbrella pole device of an electric umbrella according to an embodiment of the present disclosure. 
         FIG.  14    is a three-dimensional exploded view of the umbrella pole device of the electric umbrella in  FIG.  13   . 
         FIG.  15    is a three-dimensional structural schematic view of a second slider in  FIG.  14   . 
         FIG.  16    is a sectional view of an umbrella pole device of an electric umbrella according to an embodiment of the present disclosure. 
         FIG.  17    is a three-dimensional exploded view of the umbrella pole device of the electric umbrella in  FIG.  16   . 
         FIG.  18    is a three-dimensional structural schematic view of the telescopic device according to an embodiment of the present disclosure. 
     
    
    
     The achievement of the purpose of the present disclosure, functional characteristics and advantages will be further described with reference to the accompanying drawings in conjunction with embodiments. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The technical solutions of the embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. It is obvious that the embodiments to be described are only some rather than all of the embodiments of the present disclosure. All other embodiments obtained by persons skilled in the art based on the embodiments of the present disclosure without creative efforts shall fall within the scope of the present disclosure. 
     It should be noted that if there are directional indications, such as up, down, left, right, front, rear, etc., involved in the embodiments of the present disclosure, the directional indications are only used to explain a certain posture as shown in the accompanying drawings. If the specific posture changes, the directional indication also changes accordingly. 
     In addition, if there are descriptions related to “first”, “second”, etc. in the embodiments of the present disclosure, the descriptions of “first”, “second”, etc. are only for the purpose of description, and should not be construed as indicating or implying relative importance or implicitly indicates the number of technical features indicated. Thus, a feature delimited with “first”, “second” may expressly or implicitly include at least one of that feature. Besides, the meaning of “and/or” appearing in the disclosure includes three parallel scenarios. For example, “A and/or B” includes only A, or only B, or both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of such technical solutions does not exist or fall within the scope of protection claimed in this disclosure. 
     The present disclosure provides an electric umbrella. 
     In an embodiment of the present disclosure, as shown in  FIG.  1   , the electric umbrella  10  includes an umbrella pole device  12  and an umbrella rib device  14  arranged on the umbrella pole device  12 . When the electric umbrella  10  is opened, the umbrella pole device  12  needs to be extended, and the umbrella rib device  14  needs to be stretched. When the electric umbrella  10  is folded, the umbrella pole device  12  needs to be shortened and the umbrella rib device  14  needs to be retracted. 
     In an embodiment, the umbrella pole device  12  includes an umbrella head  100 , a middle rod  200 , an upper nest  300  and a lower nest  400 . The umbrella rib device  14  includes an umbrella rib  500  and an umbrella cloth. 
     In an embodiment, as shown in  FIG.  1    to  FIG.  3   , the umbrella head  100  includes a shell  110  and a driving assembly  120  arranged in the shell  110 . The shell  110  is provided with an umbrella opening button  112  and an umbrella retracting button  114 , both the umbrella opening button  112  and the umbrella retracting button  114  are electrically connected to the driving assembly  120 . When the umbrella opening button  112  is pressed, an output shaft of the driving assembly  120  rotates clockwise or counterclockwise. When the umbrella retracting button  114  is pressed, the output shaft of the driving assembly  120  rotates counterclockwise or clockwise. When the umbrella opening button  112  or the retracting button  114  is pressed, the rotation direction of the output shaft of the driving assembly  120  is opposite. 
     In an embodiment, the umbrella head  100  also includes a battery and an integrated circuit board arranged in the shell  110 . The battery is used to supply a power for the driving assembly  120 , the integrated circuit board and other components. The circuit board is used to control a working mode of the driving assembly  120 . The umbrella head  100  also includes a charging interface arranged at a bottom of the shell  110 , through which the battery can be charged. 
     As shown in  FIG.  1    to  FIG.  8   , the middle rod  200  includes a plurality of casings sleeved from inside to outside, and the casings can be pulled apart to form an end-to-end long rod. An innermost casing of the middle rod  200  is the inner casing  202 , and an outermost casing of the middle rod  200  is the outer casing  204 . 
     In an embodiment, one end of the inner casing  202  is connected to the shell  110  of the umbrella head  100 . In this way, after the middle rod  200  is pulled apart to form a long rod, the shell  110 , the inner casing  202  and the outer casing  204  are arranged in sequence. 
     The upper nest  300  is arranged at an end of the outer casing  204  away from the umbrella head  100 . 
     The lower nest  400  is slidably disposed on the outer casing  204 . 
     The umbrella rib  500  includes a first rib  510 , a second rib  520 , a tension spring  530  and a third rib  540 . One end of the first rib  510  is connected to the upper nest  300 . One end of the second rib  520  is connected to the lower nest  400 , and another end of the second rib  520  is slidably connected to the first rib  510 . Two ends of the tension spring  530  are respectively connected to the first rib  510  and the second rib  520 . The third rib  540  is connected to another end of the first rib  510 . 
     The umbrella cloth is arranged on the umbrella rib  500 . 
     In an embodiment, the umbrella pole device  12  also includes an umbrella pole transmission assembly  600  and an umbrella rib transmission assembly  700 . The umbrella pole transmission assembly  600  is cooperated with the umbrella pole transmission assembly  700 , so that when the umbrella opening button  112  is pressed, the driving assembly  120  can open the electric umbrella  10  through the umbrella pole transmission assembly  600  and the umbrella rib transmission assembly  700 . When the umbrella retracting button  114  is pressed, the driving assembly  120  can retract the electric umbrella  10  through the umbrella pole transmission assembly  600  and the umbrella rib transmission assembly  700 . 
     In an embodiment, the umbrella pole transmission assembly  600  is arranged in the middle rod  200  of the electric umbrella  10 . When the umbrella pole transmission assembly  600  exerts a force on the middle rod  200 , the multiple casings of the middle rod  200  can be pulled apart to form the end-to-end long rod, so that the umbrella pole of the electric umbrella  10  is extended. After the force exerted by the umbrella pole transmission assembly  600  on the middle rod  200  is canceled, under a force of the tension spring  530 , the multiple casings of the middle rod  200  can get sleeved from inside to outside, thereby completing a step of shortening the umbrella pole of the electric umbrella  10 . 
     In an embodiment, the umbrella pole transmission assembly  600  exerts a force on the upper nest  300 , the upper nest  300  is arranged at the end of the outer casing  204  away from the umbrella head  100 , so that the umbrella pole transmission assembly  600  indirectly exerts the force on the outer casing  204  through the upper nest  300 . 
     In an embodiment, as shown in  FIG.  3    to  FIG.  17   , the umbrella pole transmission assembly  600  is arranged in the inner casing  202 . The umbrella pole transmission assembly  600  includes a first transmission tube  610  and a second transmission tube  620 , the first transmission tube  610  is telescopically sleeved with the second transmission tube  620 , one of the first transmission tube  610  and the second transmission tube  620  is a rectangular spring, and one end of the first transmission tube  610  is rotatably connected to the umbrella head  100 . 
     When the first transmission tube  610  rotates in a first direction, the second transmission tube  620  can move (screw out) toward a direction away from the umbrella head  100 , and can apply a force to the outer casing  204 , so that the multiple casings of the middle rod  200  can be pulled apart to form the end-to-end long rod. In this way, the umbrella pole of the electric umbrella  10  is extended. 
     When the first transmission tube  610  rotates in a second direction, the second transmission tube  620  can move (screw in) towards a direction close to the umbrella head  100  to return to an original position, thereby canceling the force exerted on the outer casing  204 . In this way, under an action of other elements, the multiple casings of the middle rod  200  can get sleeved from inside to outside, so as to complete a step of shortening the umbrella pole of the electric umbrella  10 . 
     The first direction is opposite to the second direction, for example, when the first direction is clockwise, the second direction is counterclockwise. When the first direction is counterclockwise, the second direction is clockwise. 
     In the umbrella pole transmission assembly  600 , one end of the first transmission tube  610  is rotatably connected to the umbrella head  100 , and the first transmission tube  610  is telescopically sleeved with the second transmission tube  620 . When the first transmission tube  610  rotates, the second transmission tube  620  can move towards the end away from the umbrella head  100 , and can apply the force to the outer casing  204 , so that the multiple casings of the middle rod  200  are pulled apart to form the end to end long rod. In this way, a compression of the first transmission tube  610  and the second transmission tube  620  can be avoided, that is, a compression of the rectangular spring can be avoided. Therefore, when the first transmission tube  610  is connected to the driving assembly  120 , and is driven to rotate by the driving assembly  120 , a torque requirement for the driving assembly  120  is relatively low. The driving assembly  120  with a small torque can be used to drive the first transmission tube  610  to rotate, and the driving assembly  120  with a small torque is generally smaller in size, thereby reducing a size of the umbrella head  100  and miniaturizing the electric umbrella  10 . Moreover, in an actual production and manufacturing, a price of the rectangular spring is far lower than that of the threaded rod when the same effect is achieved, and a use of the rectangular spring as the transmission tube can reduce a production cost of the electric umbrella  10 . 
     It should be noted that the rectangular spring is also called as a mold spring, because a material is a square wire (an ordinary spring is made of a round wire material), and a cross section of the square wire is rectangular, so it is called the rectangular spring. 
     In an embodiment, as shown in  FIG.  3    to  FIG.  12   , the second transmission tube  620  is a rectangular spring  620   a , and the rectangular spring  620   a  is sleeved outside the first transmission tube  610 . 
     In an embodiment, as shown in  FIG.  3    to  FIG.  8   , the umbrella pole transmission assembly  600  further includes a guiding spring portion  630  and a first slider  640 . The guiding spring portion  630  is arranged at an end of the first transmission tube  610  away from the umbrella head  100 . The guiding spring portion  630  is provided with a first guiding spring passage  632 . At least part of the coils  622   a  of the rectangular spring  620   a  are arranged in the first guiding spring passage  632 . The first slider  640  is slidably sleeved outside the first transmission tube  610 , and is arranged between the umbrella head  100  and the rectangular spring  620   a , the first slider  640  is connected to an end of the rectangular spring  620   a  near the umbrella head  100 , and the first slider  640  can confine a relative rotation between the rectangular spring  620   a  and the guiding spring portion  630 . 
     When the first transmission tube  610  rotates, the guiding spring portion  630  is driven to rotate, and the first slider  640  can confine a relative rotation between the rectangular spring  620   a  and the guiding spring portion  630 , so that the rectangular spring  620   a  can move on the first transmission tube  610  and perform a linear motion while being aligned with the guiding spring portion  630  to rotate synchronously. Moreover, the first slider  640  is slidably sleeved outside the first transmission tube  610 , and is connected to the end of the rectangular spring  620   a  close to the umbrella head  100 , so that the first slider  640  can also move on the first transmission tube  610  and perform the linear motion while the rectangular spring  620   a  is performing the linear motion. 
     When the first transmission tube  610  rotates in the first direction, the rectangular spring  620   a  and the first slider  640  move on the first transmission tube  610  toward the direction away from the umbrella head  100 , so that the rectangular spring  620   a  extends (screws in) from an end of the guiding spring portion  630  away from the first transmission tube  610 , and exerts the force on the middle rod  200 , so that multiple casings of the middle rod  200  are pulled apart to form the end to end long rod. In this way, the umbrella pole of the electric umbrella  10  will be extended. 
     When the first transmission tube  610  rotates in the second direction, the rectangular spring  620   a  and the first slider  640  move on the first transmission tube  610  towards the direction close to the umbrella head  100 . The rectangular spring  620   a  extends (screw in) to the end of the guiding spring portion  630  away from the first transmission tube  610  can return to the original position, thereby canceling the force exerted by the rectangular spring  620   a  on the middle rod  200 . In this way, under the action of other elements, the multiple casings of the middle rod  200  can be sleeved from inside to outside, so as to complete the step of shortening the umbrella pole of the electric umbrella  10 . 
     In an embodiment, through setting the first slider  640  not to rotate, the relative rotation between the rectangular spring  620   a  and the guiding spring portion  630  is confined through the first slider  640 . 
     In an embodiment, an outer wall of the first slider  640  is cooperated with the inner wall of the inner casing  202  to confine the rotation of the first slider  640 , but the inner wall of the first slider  640  is not cooperated with the outer wall of the first transmission tube  610 , thus cannot confine the rotation of the first slider  640 . That is, the first slider  640  cannot rotate in the inner casing  202 , but the first transmission tube  610  can rotate in the first slider  640 . 
     In an embodiment, both the outer wall of the first slider  640  and the inner wall of the inner casing  202  are in a multi-faceted structure, and face numbers of the outer wall of the first slider  640  is the same as those of the inner wall of the inner casing  202 , which are correspondingly set. In an embodiment, the outer wall of the first slider  640  has a regular hexagonal structure, and the inner wall of the inner casing  202  also has the regular hexagonal structure. 
     In an embodiment, the outer wall of the first transmission tube  610  may be a cylindrical structure, or a multi-faceted structure. The inner wall of the first slider  640  is separated from the outer wall of the first transmission tube  610  by a first distance, and the inner wall of the rectangular spring  620   a  is separated from the outer wall of the first transmission tube  610  by a second distance. Both the first distance and the second distance are satisfied, and neither the inner wall of the first slider nor the inner wall of the rectangular spring  620   a  interferes with the rotation of the first transmission tube  610 . 
     In an embodiment shown in  FIG.  3    to  FIG.  8   , the middle rod  200  includes two casings. At this time, the middle rod  200  belongs to a two-fold electric umbrella. 
     In an embodiment, as shown in  FIG.  9    to  FIG.  12   , the umbrella pole transmission assembly  600  includes a threaded tube  650 , an external transmission tube  660  and a nut  670 . 
     One end of the threaded tube  650  is rotatably connected to the umbrella head  100 . 
     The first transmission tube  610  is slidably inserted into an end of the threaded tube  650  away from the umbrella head  100 . The outer wall of the first transmission tube  610  is cooperated with the inner wall of the threaded tube  650  to confine the relative rotation between the first transmission tube  610  and the threaded tube  650 . That is, when the threaded tube  650  rotates, the first transmission tube  610  is linked with the threaded tube  650  and rotates synchronously with the threaded tube  650 , so that the first transmission tube  610  does not rotate relative to the threaded tube  650 . 
     The external transmission tube  660  is slidably sleeved on the threaded tube  650 , when the external transmission tube  660  slides on the threaded tube  650 , the first transmission tube  610  and the guiding spring portion  630  are driven to slide. 
     The nut  670  is sleeved on the outside of the threaded tube  650  and is screwed to the threaded tube  650 . The outer wall of the nut  670  is cooperated with the inner wall of the inner casing  202  so that the nut  670  can move on the threaded tube  650 . The nut  670  is arranged between the umbrella head  100  and the external transmission tube  660 , and is fixedly connected to the end of the external transmission tube  660  close to the umbrella head  100 . 
     Both the rectangular spring  620   a  and the first slider  640  are slidably sleeved outside the external transmission tube  660 , and the inner wall of the first slider  640  is cooperated with the outer wall of the external transmission tube  660  to confine the rotation of the first slider  640 . 
     When the threaded tube  650  rotates, the first transmission tube  610  is driven to rotate, then the guiding spring portion  630  is driven to rotate, while the first slider  640  is confined by the outer wall of the external transmission tube  660  and cannot rotate, so that the rectangular spring  620   a  can slide on the external transmission tube  660  while rotating synchronously with the guiding spring portion  630  to perform the linear motion. Moreover, the first slider  640  is slidably sleeved on the external transmission tube  660 , and is connected to the end of the rectangular spring  620   a  close to the umbrella head  100 , so that the first slider  640  can also move on the external transmission tube  660  while the rectangular spring  620   a  is performing the linear motion. In addition, when the threaded tube  650  rotates, the outer wall of the nut  670  is cooperated with the inner wall of the inner casing  202  so that the nut  670  can move on the threaded tube  650 , so that the nut  670  can drive the external transmission tube  660  to slide on the threaded tube  650  to perform the linear motion, and the external transmission tube  660  can drive the first transmission tube  610  and the guiding spring portion  630  to slide and perform the linear motion. 
     Since the external transmission tube  660 , the first transmission tube  610  and the guiding spring portion  630  can perform the linear motion, a displacement of the linear motion of the rectangular spring  620   a  is larger, which is suitable for the middle rod  200  with three or more folds. 
     In an embodiment, when the middle rod  200  belongs to an electric umbrella with three or more folds and the middle rod  200  includes three or more casings, a middle tube  206  is arranged between the inner casing  202  and the outer casing  204 . An amount of the middle tube  206  is greater than or equal to one. In an embodiment shown in  FIG.  8    to  FIG.  11   , the number of the middle tube  206  is equal to 1, and the middle rod  200  belongs to the three-fold electric umbrella. 
     In an embodiment, the umbrella pole transmission assembly  600  further includes a T-shaped cylindrical pin  680  and a bushing  690 . The T-shaped cylindrical pin  680  is sleeved outside of the first transmission tube  610 , and an inner wall of the T-shaped cylindrical pin  680  is cooperated with the outer wall of the first transmission tube  610  to confine the rotation of the T-shaped cylindrical pin  680 . 
     The guiding spring portion  630  is sleeved outside the T-shaped cylindrical pin  680 , and a head end  682  of the T-shaped cylindrical pin  680  is arranged between the guiding spring portion  630  and the umbrella head  100 . 
     The bushing  690  is sleeved outside the first transmission tube  610 , and an end of the bushing  690  away from the umbrella head  100  is rotatably connected to the head end  682  of the T-shaped cylindrical pin  680 . The end of the external transmission tube  660  away from the umbrella head  100  is sleeved on the outside of the casing  690 . Thus, when the external transmission tube  660  slides on the threaded tube  650 , the first transmission tube  610  and the guiding spring portion  630  can be driven to slide. 
     In an embodiment, both the outer wall of the first transmission tube  610  and the inner wall of the threaded tube  650  have the multi-faceted structure, and face numbers of the outer wall of the first transmission tube  610  is the same as those of the inner wall of the threaded tube  650 , which are correspondingly set. Specifically, in an embodiment, the outer wall of the first transmission tube  610  has a regular five-sided structure, and the inner wall of the threaded tube  650  also has the regular five-sided structure. 
     In an embodiment, both the outer wall of the nut  670  and the inner wall of the inner casing  202  have the multi-faceted structure, and face numbers of the outer wall of the nut  670  is the same as those of the inner wall of the inner casing  202 , which are correspondingly set. Specifically, in an embodiment, the outer wall of the nut  670  has the regular hexagonal structure, and the inner wall of the inner casing  202  also has the regular hexagonal structure. 
     In an embodiment, both the inner wall of the first slider  640  and the outer wall of the external transmission tube  660  have the multi-faceted structure, and face numbers of the inner wall of the first slider  640  is the same as those of the outer wall of the external transmission tube  660 , which are correspondingly set. Specifically, in an embodiment, the inner wall of the first slider  640  has the regular five-sided structure, and the outer wall of the external transmission tube  660  also has the regular five-sided structure. 
     In an embodiment, both the inner wall of the T-shaped cylindrical pin  680  and the outer wall of the first transmission tube  610  have the multi-faceted structure, and face numbers of the inner wall of the T-shaped cylindrical pin  680  is the same as those of the outer wall of the first transmission tube  610 , which are correspondingly set. Specifically, in an embodiment, the inner wall of the T-shaped cylindrical pin  680  has the regular five-sided structure, and the outer wall of the first transmission tube  610  also has the regular five-sided structure. 
     When the threaded tube  650  rotates, the first transmission tube  610  is driven to rotate, the T-shaped cylindrical pin  680  is driven to rotate synchronously by the first transmission tube  610 , so that the guiding spring portion  630  is driven to rotate by the T-shaped cylindrical pin  680 , but the first slider  640  is confined by the outer wall of the external transmission tube  660  and cannot rotate, so that the rectangular spring  620   a  can slide on the external transmission tube  660  while rotating synchronously with the guiding spring portion  630  to perform the linear motion. Moreover, the first slider  640  is slidably sleeved on the external transmission tube  660 , and is connected to the end of the rectangular spring  620   a  close to the umbrella head  100 , so that the first slider  640  can also move on the external transmission tube  660  while the rectangular spring  620   a  is performing the linear motion. In addition, when the threaded tube  650  rotates, the outer wall of the nut  670  is cooperated with the inner wall of the inner casing  202  so that the nut  670  can move on the threaded tube  650 , so that the external transmission tube  660  can be driven by the nut  670  to slide on the threaded tube  650  to perform the linear motion, then the first transmission tube  610  and the guiding spring portion  630  can be driven by the external transmission tube  660  to slide through the bushing  690  and perform the linear motion. 
     Referring to embodiments shown in  FIG.  3    to  FIG.  12   , the umbrella pole transmission assembly  600  further includes a first reinforcing tube  602  sleeved outside the rectangular spring  620   a , the first reinforcing tube  602  is relatively fixed to the rectangular spring  620   a . An integrity of the first reinforcing tube  602  and the rectangular spring  620   a  can effectively increase a supporting force of the rectangular spring  620   a , so that when the umbrella pole of the electric umbrella  10  is extended, the rectangular spring  620   a  can be effectively prevented from swinging. 
     In an embodiment, one end of the first reinforcing tube  602  close to the umbrella head  100  is connected to the first slider  640 . In this way, both the first reinforcing tube  602  and the rectangular spring  620   a  are connected to the first slider  640 , so that the first reinforcing tube  602  and the rectangular spring  620   a  are relatively fixed. 
     In an embodiment, an end of the first reinforcing tube  602  close to the umbrella head  100  is connected to the first slider  640 , and an end of the first reinforcing tube  602  away from the umbrella head  100  is connected to the outer casing  204 . In this way, a connection of the first reinforcing tube  602  can be made more stable. It can be understood that, in other embodiments, the end of the first reinforcing tube  602  close to the umbrella head  100  may also be connected to the first slider  640 , or the end of the first reinforcing tube  602  away from the umbrella head  100  may be connected to the outer casing  204 . 
     In an embodiment, as shown in  FIG.  13    to  FIG.  15   , the first transmission tube  610  is the rectangular spring  610   a , and the second transmission tube  620  is sleeved outside the rectangular spring  610   a.    
     The umbrella pole transmission assembly  600  also includes a second slider  604 . The second slider  604  is sleeved outside the rectangular spring  610   a . The second slider  604  is arranged between the umbrella head  100  and the second transmission tube  620 , and is fixedly connected to the end of the second transmission tube  620  close to the umbrella head  100 . 
     The inner wall of the second slider  604  is provided with a second guiding spring passage  6042 , and at least part of the coils of the rectangular spring  610   a  are arranged in the second guiding spring passage  6042 . The outer wall of the second slider  604  is cooperated with the inner wall of the inner casing  202  so that the second slider  604  can move on the rectangular spring  610   a . A principle that the second slider  604  moves on the rectangular spring  610   a  is similar to a threaded connection between a stud and a nut. 
     In the umbrella pole transmission assembly  600 , when the rectangular spring  610   a  rotates, because the outer wall of the second slider  604  is cooperated with the inner wall of the inner casing  202 , the relative rotation of the first slider  640  and the rectangular spring  610   a  can be confined, so that the second slider  604  can move on the rectangular spring  610   a  and perform the linear motion. The second transmission tube  620  is fixed on the second slider  604 , so that when the second slider  604  performs the linear motion, the second transmission tube  620  can also move on the rectangular spring  610   a  to perform the linear motion. 
     In an embodiment, both the inner wall of the second slider  604  and the outer wall of the inner casing  202  have the multi-faceted structure, and face numbers of the inner wall of the second slider  604  is the same as those of the outer wall of the inner casing  202 , which are correspondingly set. Specifically, in an embodiment, the inner wall of the second slider  604  has the regular hexagonal structure, and the outer wall of the inner casing  202  also has the regular hexagonal structure. 
     In an embodiment, the umbrella pole transmission assembly  600  further includes a second reinforcing tube  606 . The rectangular spring  610   a  is sleeved outside the second reinforcing tube  606  and is relatively fixed to the second reinforcing tube  606 . One end of the second reinforcing tube  606  close to the umbrella head  100  is rotatably connected to the umbrella head  100 . An integrity of the rectangular spring  610   a  and the second reinforcing tube  606  can effectively increase a supporting force of the rectangular spring  610   a , so that when the umbrella pole of the electric umbrella  10  is extended, the rectangular spring  610   a  can be effectively prevented from swinging. Moreover, the rectangular spring  610   a  can also be rotatably connected to the umbrella head  100  through the second reinforcing tube  606 , which facilitates the rotatable connection of the rectangular spring  610   a  and the umbrella head  100 . 
     In an embodiment, the umbrella pole transmission assembly  600  further includes a mounting portion  608  rotatably connected to the umbrella head  100 , and the second reinforcing tube  606  and the rectangular spring  610   a  are both fixed on the installation part  608 . 
     In an embodiment, the rectangular spring  610   a  is interference fit with the second reinforcing tube  606 . In this way, it is more convenient for the second slider  604  to move on the rectangular spring  610   a . Specifically, in an embodiment, an outer diameter of the second reinforcing tube  606  is equal to or slightly larger than an inner diameter of the rectangular spring  610   a.    
     In an embodiment, as shown in  FIG.  16    and  FIG.  17   , the first transmission tube  610  is the rectangular spring  610   a  sleeved outside the second transmission tube  620 . 
     The umbrella pole transmission assembly  600  also includes a third slider  601  and an anti-rotation block  603 . 
     The rectangular spring  610   a  is sleeved outside the third slider  601 . The third slider  601  is fixedly connected to an end of the second transmission tube  620  close to the umbrella head  100 . An outer wall of the third slider  601  is provided with a third guiding spring passage  6012 , and at least part of the coils of the rectangular spring  610   a  are arranged in the third guiding spring passage  6012 . 
     The anti-rotation block  603  is arranged on the end of the inner casing  202  away from the umbrella head  100 , and the second transmission tube  620  is slidably inserted on the anti-rotation block  603 . An inner wall of the anti-rotation block  603  is cooperated with the outer wall of the second transmission tube  620  so that the third slider  601  can move on the rectangular spring  610   a.    
     In the umbrella pole transmission assembly  600 , when the rectangular spring  610   a  rotates, because the inner wall of the anti-rotation block  603  is cooperated with the outer wall of the second transmission tube  620 , the relative rotation between the second transmission tube  620  and the rectangular spring  610   a  can be confined, so that a relative rotation between the third slider  601  and the rectangular spring  610   a  can be confined, and the third slider  601  can move on the rectangular spring  610   a  to perform the linear motion. The second transmission tube  620  is fixed on the third slider  601 , and the second transmission tube  620  is slidably inserted on the anti-rotation block  603 , so that when the third slider  601  performs the linear motion, the second transmission tube  620  can also move on the rectangular spring  610   a  and perform the linear motion. 
     In an embodiment, both the inner wall of the anti-rotation block  603  and the outer wall of the second transmission tube  620  have the multi-faceted structure, and face numbers of the inner wall of the anti-rotation block  603  is the same as those of the outer wall of the second transmission tube  620 , which are correspondingly set. Specifically, in an embodiment, the inner wall of the anti-rotation block  603  has the regular five-sided structure, and the outer wall of the second transmission tube  620  also has the regular five-sided structure. 
     In an embodiment, the umbrella pole transmission assembly  600  further includes a third reinforcing tube  605  sleeved outside the rectangular spring  610   a  and the third reinforcing tube  605  is relatively fixed to the rectangular spring  610   a . An integrity of the rectangular spring  610   a  and the third reinforcing tube  605  can effectively increase the supporting force of the rectangular spring  610   a , so that when the umbrella pole of the electric umbrella  10  is extended, the rectangular spring  610   a  can be effectively prevented from swinging. Moreover, the rectangular spring  610   a  can also be rotatably connected to the umbrella head  100  through the third reinforcing tube  605 , which facilitates the rotatable connection of the rectangular spring  610   a  and the umbrella head  100 . 
     In an embodiment, the umbrella pole transmission assembly  600  further includes a first connecting block  607  and a second connecting block  609 . Two ends of the rectangular spring  610   a  are respectively sleeved on the first connecting block  607  and the second connecting block  609 , and the third slider  601  is arranged between the first connecting block  607  and the second connecting block  609 . Two ends of the third reinforcing tube  605  are respectively sleeved on the first connecting block  607  and the second connecting block  609 . The first connecting block  607  is rotatably connected to the umbrella head  100 . 
     In an embodiment, as shown in  FIG.  1    to  FIG.  17   , the electric umbrella  10  further includes an umbrella rib transmission assembly  700  cooperated with the umbrella pole transmission assembly  600 . When the umbrella pole transmission assembly  600  completes the step of opening the umbrella pole of the electric umbrella  10 , the umbrella rib transmission assembly  700  stretches the umbrella rib  500  of the electric umbrella  10 . After the force exerted on the middle rod  200  by the umbrella pole transmission assembly  600  is canceled, under an action of the tension spring  530 , the umbrella rib transmission assembly  700  retracts the umbrella rib  500  of the electric umbrella  10 , the multiple casings of the middle rod  200  get sleeved from inside to outside, and the step of shortening the umbrella pole of the electric umbrella  10  is completed. 
     In an embodiment, the umbrella rib transmission assembly  700  includes at least one upper pulley  710 , at least one lower pulley  720 , and a stay rope  730 . The upper pulley  710  is provided on the upper nest  300 , and the lower pulley  720  is arranged on the lower nest  400 . One end of the stay rope  730  is fixed on the umbrella head  100 , and another end of the stay rope  730  passes through the transmission tube  620 , alternately goes around the upper pulley  710  and the lower pulley  720 , and is fixed on the upper nest  300  or the lower nest  400 . 
     When using the electric umbrella  10 , after pressing the umbrella opening button  112 , the driving assembly  120  rotates, the first transmission tube  610  is driven to rotate, and the second transmission tube  620  is unscrewed. After a force is applied to the upper nest  300 , the upper nest  300  fixed on the outer casing  204  moves away from the umbrella head  100 , so that the multiple casings of the middle rod  200  are pulled apart to the form the end-to-end long rod, and the step of opening the umbrella pole of the electric umbrella  10  is completed. Because the upper nest  300  fixed on the outer casing  204  moves away from the umbrella head  100 , the stay rope  730  will pull the lower nest  400  to slide on the outer casing  204  towards the upper nest  300 , the second umbrella rib  520  is driven to slide on the first umbrella rib  510 , thereby opening the umbrella rib  500 , and the step of opening the umbrella rib  500  of the electric umbrella  10  is completed. At this time, the electric umbrella  10  is in an open state, and the tension spring  530  is in a compressed state. 
     Then press the umbrella retracting button  114 , the driving assembly  120  rotates reversely to drive the first transmission tube  610  to rotate, the second transmission tube  620  is screwed in, and the force exerted on the upper nest  300  by the second transmission tube  620  is canceled. The lower nest  400  moves toward the umbrella handle  100  by the tension of the tension spring  530 , inwardly retracts the second umbrella rib  520  and the first umbrella rib  510 , and the step of retracting the umbrella rib  500  of the electric umbrella  10  is completed. The lower pulley  720  drives the stay rope  730  to pull the upper nest  300 , so that the upper nest  300  drives the outer casing  204  to move toward the umbrella handle  100 , the inner casing  202 , the middle tube  206  and the outer casing  204  get sequentially sleeved from inside to outside, and the step of folding the umbrella pole of the electric umbrella  10  is completed. 
     Under the action of the tension spring  530 , the second umbrella rib  520  slides reversely on the first umbrella rib  510 , the stay rope  730  will pull the lower nest  400  and the upper nest  300  to slide towards the umbrella head  100  on the outer casing  204 , and the step of retracting the umbrella rib  500  of the umbrella  10  is completed. The multiple casings of the middle rod  200  get sleeved from inside to outside, and the step of folding the umbrella pole of the electric umbrella  10  is completed. 
     In an embodiment, an amount of the upper pulley  710  and the lower pulley  720  is 1. One end of the stay rope  730  is fixed to the umbrella head  100 , and another end of the rope  730  passes through an innermost tube of the umbrella pole transmission assembly  600  (in an embodiment shown in  FIG.  3    to  FIG.  12   , the innermost tube is the first transmission tube  610 , in an embodiment shown in  FIG.  13    to  FIG.  15   , the innermost tube is the second reinforcing tube  606 , in an embodiment shown in  FIG.  16    and  FIG.  17   , the innermost tube is the second transmission tube  620 ). The stay rope  730  bypasses the upper pulley  710  and the lower pulley  720  in sequence, then the other end of the stay rope  730  is fixed on the upper nest  300 . In this way, the stay rope  730  is divided into three sections. Correspondingly, in an embodiment, an amount of the middle tube  206  is 1, that is, the middle rod  200  includes three casings. Correspondingly, the electric umbrella  10  is a three-fold electric umbrella. 
     In other embodiments, when it is necessary to design a four-fold or even a five-fold electric umbrella, by setting a corresponding number of the upper pulley  710 , the lower pulley  720 , the stay rope  730  is divided into four sections, or even five sections, and the middle rod  200  includes four or even five casings. 
     In an embodiment, as shown in  FIG.  3   , the driving assembly  120  includes a motor  122 , a main gear  124 , a slave gear  126  and a gearbox. The main gear  124  is arranged on an output shaft of the motor  122 , the slave gear  126  is sleeved on an end of the first transmission tube  610  close to the umbrella head  100 , and a speed change gear of the gearbox is respectively engaged with the main gear  124  and the slave gear  126 . 
     According to the  FIG.  1    to  FIG.  17   , the present disclosure also provides a telescopic device including a mounting seat, a casing assembly and an inner transmission assembly. The mounting seat is the umbrella head  100 , the casing assembly is the middle rod, and the inner transmission assembly is the umbrella pole transmission assembly  600 . 
     It should be noted that the installation seat is the umbrella head  100 , which means that the installation seat not only includes part of or all of the elements in the embodiment shown in  FIG.  3    to  FIG.  17   , but may also include other elements. 
     The casing assembly is the middle rod  200 , which means that the casing assembly not only includes part of or all of the elements in the embodiment shown in  FIG.  3    to  FIG.  17   , but may also include other elements. 
     The inner transmission assembly is the umbrella pole transmission assembly  600 , which means that the inner transmission assembly not only includes part of or all of the elements in the embodiment shown in  FIG.  3    to  FIG.  17   , but may also include other elements. 
     In an embodiment, the telescopic device can be applied to a selfie stick, a clothes rail or a robot. That is, the selfie stick, the clothes rail or a robot, which includes the telescopic device. At this time, as shown in  FIG.  18   , the end of the outer casing  204  away from the installation seat is provided with a clamp positioning member  800 . 
     When the telescopic device is applied to the selfie stick, the clamp positioning member  800  is used to fix a mobile phone or a camera. When the telescopic device is applied to the clothes rail, the clamp positioning member  800  is a fork. When the telescopic device is applied to the robot, the clamp positioning member  800  is a manipulator. 
     The above descriptions are only embodiments of the present disclosure, and are not intended to limit the scope of the present disclosure. Under the inventive concept of the present disclosure, any equivalent structural transformations made by using the contents of the description and drawings of the present disclosure, or direct/indirect disclosures in other related technical fields are included in the scope of the present disclosure.