Patent Publication Number: US-11661783-B1

Title: Electric support rod

Description:
BACKGROUND OF THE DISCLOSURE 
     Technical Field 
     This disclosure is directed to an electric support rod of a tailgate of a car and in particular to a two-segment electric support rod which is easy to be assembled. 
     Description of Related Art 
     A related-art electric tailgate of a car is supported and driven by electric support rods arranged at two sides of a door frame. The electric support rod has an electric motor and a telescopic pole linked with the electric motor, the telescopic pole can be driven to telescope by controlling the electric motor to rotate so as to open or close the tailgate. 
     In general, the electric support rod has an outer tube, and the telescopic pole and the electric motor are inserted in the outer tube. The telescopic pole has a screw rod connected to the electric motor, and a bearing for fixing the screw rod is arranged between the screw rod and the outer tube. An inner edge of the bearing needs to be tightly fit with the screw rod and an outer edge of the bearing needs to be tightly fit with an inner wall of the outer tube. Furthermore, the outer tube is relatively long, and the bearing is therefore difficult to be assembled. 
     In view of the above drawbacks, the inventor proposes this disclosure based on his expert knowledge and elaborate researches in order to solve the problems of related art. 
     SUMMARY OF THE DISCLOSURE 
     This disclosure is directed to a two-segment electric support rod which is easy to be assembled. 
     This disclosure is directed to an electric support rod having a driving assembly, an actuating assembly, and a bearing. The driving assembly has a first outer tube and a driving unit accommodated in the first outer tube, the first outer tube has a first engaging end and an internal thread arranged on an inner surface of the first engaging end. The actuating assembly has a second outer tube and a transmission screw rod inserted in the second outer tube, the second outer tube has a second engaging end and a plurality of elastic arms. The elastic arms are axially extended from the second engaging end and disposed spacedly around the transmission screw rod. Each elastic arm has an internal surface facing the transmission screw rod and an external surface opposite to the transmission screw rod. An outer thread structure is arranged on the external surface, a hook portion is disposed protrusively from the internal surface. The second engaging end is inserted in the first engaging end, the internal thread is screwed with the outer thread structure, and one end of the transmission screw rod protrudes from the second outer tube to be engaged the driving unit. The bearing is adapted to sheathe the transmission screw rod, and the hook portion latches an outer edge of the bearing. 
     According to the electric support rod of this disclosure, the outer edge of the bearing is attached on the internal surface of the elastic arm. 
     According to the electric support rod of this disclosure, the actuating assembly further has a telescopic set inserted in the second outer tube and adapted to sheathe the transmission screw rod, and the telescopic set has a nut screwed with the transmission screw rod. 
     According to the electric support rod of this disclosure, the transmission screw rod has a transmission thread, the transmission screw rod has a tenon laterally inserted in the transmission screw rod, and the bearing is clamped between one end of the transmission thread and the tenon. 
     According to the electric support rod of this disclosure, each outer thread structure has a plurality of thread segments disposed parallelly, and the thread segments of the outer thread structure are configured with the internal thread in the same helix line. 
     According to the electric support rod of this disclosure, an outer surface of the second outer tube has an external thread extended from any one of the outer thread structures, and the external thread and the thread segments of the outer thread structures are configured with the internal thread in the same helix line. The outer surface of the second outer tube has a connecting surface, the connecting surface is attached on the inner surface of the first outer tube. The external thread is disposed between the connecting surface and the outer thread structure and is screwed with the internal thread. The connecting surface is a curved annular surface surrounding a lateral side of the second outer tube. 
     Accordingly, the driving unit of the electric support rod of this disclosure may be preassembled to the first outer tube. The telescopic set, the transmission screw rod and the bearing may be preassembled to the second outer tube, and then the first outer tube may be engaged with the second outer tube so that the transmission screw rod is power connected with the driving unit and the bearing is positioned. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features of the disclosure believed to be novel are set forth with particularity in the appended claims. The disclosure itself, however, may be best understood by reference to the following detailed description of the disclosure, which describes a number of exemplary embodiments of the disclosure, taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a perspective view showing an electric support rod according to an embodiment of this disclosure. 
         FIG.  2    is an exploded view of the electric support rod according to the aforementioned embodiment of this disclosure. 
         FIG.  3    is a perspective view showing an actuating assembly of the electric support rod according to an embodiment of this disclosure. 
         FIG.  4    is a cross-sectional view of the electric support rod along a longitudinal direction according to the aforementioned embodiment of this disclosure showing that the driving assembly is separated from the actuating assembly the electric support rod. 
         FIG.  5    is a cross-sectional view of the electric support rod along a longitudinal direction according to the aforementioned embodiment of this disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The technical contents of this disclosure will become apparent with the detailed description of embodiments accompanied with the illustration of related drawings as follows. It is intended that the embodiments and drawings disclosed herein are to be considered illustrative rather than restrictive. 
     According to an embodiment of this disclosure shown in  FIGS.  1  to  5   , this disclosure is directed to an electric support rod having a driving assembly  100 , an actuating assembly  200  and a bearing  300 . 
     According to this embodiment, the driving assembly  100  has a first outer tube  110  and a driving unit  130  accommodated in the first outer tube  110 . The first outer tube  110  has a first engaging end  111 , the first engaging end  111  has an opening  101 , and an internal thread  112  is arranged on an inner surface of the first engaging end  111 . According to this embodiment, the driving unit  130  at least has a motor. 
     The actuating assembly  200  has a second outer tube  210  and a transmission screw rod  230  inserted in the second outer tube  210 . The second outer tube  210  has a second engaging end  211 , and a plurality of elastic arms  220 . The elastic arms are extended from the second engaging end  211  along an axial direction of the second outer tube  210  and disposed around the transmission screw rod  230  at intervals. Each elastic arm  220  has an internal surface  220   a  facing the transmission screw rod  230  and an external surface  220   b  opposite to the transmission screw rod  230 , an outer thread structure  222  is arranged on each external surface  220   b , a hook portion  223  is disposed protrusively on each internal surface  220   a . Each outer thread structure  222  has a plurality of thread segments  222   a  disposed parallelly, each thread segment  222   a  is extended across the elastic arm  220  where the thread segment  222   a  is located, and the thread segments  222   a  are configured with the internal thread  112  in the same helix line. 
     An outer surface of the second outer tube  210  has a connecting surface  224  and an external thread  221 , the connecting surface  224  is a curved annular surface surrounding a lateral side of the second outer tube  210 , and the external thread  221  is configured between the connecting surface  224  and the outer thread structures  222 . The external thread  221  extended from any one of the outer thread structures  222 , and the external thread  221  and the thread segments  222   a  of the outer thread structures  222  configured with the internal thread  112  in the same helix line. 
     The transmission screw rod  230  has a transmission thread  231 , the transmission screw rod  230  is provided with a tenon  232  which is inserted into the transmission screw rod  230  along a lateral direction of the transmission screw rod  230 , and the bearing  300  is clamped between one end of the transmission thread  231  and the tenon  232 . According to this embodiment, the tenon  232  is a C-clip, but scope of this disclosure should not be limited to the aforementioned embodiment. For example, the tenon  232  may be a pin inserted into the transmission screw rod  230 . 
     The actuating assembly  200  further has a telescopic set  240  inserted in the second outer tube  210  and adapted to sheathe the transmission screw rod  230 . The telescopic set  240  has a plurality of tubes movably sheathed with one another, thereby telescoping for varying a length of the telescopic set  240 . Moreover, the telescopic set  240  has a nut  241  screwed with the transmission screw rod  230 , the nut  241  is connected to one of the tubes, the nut  241  is moved along a longitudinal direction of the transmission screw rod  230  when the transmission screw rod  230  is rotated, so as to drive the telescopic set  240  to telescope. 
     According to this embodiment, the bearing  300  is of a ring shape, the bearing  300  sheathes the transmission screw rod  230  and an inner edge thereof is tightly fit with the transmission screw rod  230 . An outer diameter of the bearing  300  is fit with a ring enclosed by the internal surfaces  220   a  of the elastic arm  220 . The bearing  300  is put into the second outer tube  210  along a longitudinal direction of the second outer tube  210 , the bearing  300  presses the hook portions  223  when moves into the second outer tube  210  so as to outward push the elastic arms  220 . The bearing  300  passes the hook portions  223  and then the elastic arms  220  return inward so that an outer edge of the bearing  300  is attached with the internal surfaces  220   a  of the elastic arms  220 , and the hook portions  223  latch the outer edge of the bearing  300  to fix the bearing  300  in the second outer tube  210 . 
     The second engaging end  211  is inserted into the first engaging end  111  through the opening  101 , the internal thread  112  is screwed with the outer thread structures  222 , and the external thread  221  is screwed with the internal thread  112 , so that the first outer tube  110  is connected with the second outer tube  210 . One end of the transmission screw rod  230  protrudes from the second outer tube  210  to be engaged the driving unit  130 , and the transmission screw rod  230  and the motor of the driving unit  130  are co-axially disposed. The first outer tube  110  and the second outer tube  210  may be further welded to fix with each other. According to this embodiment, the connecting surface  224  is attached with the inner surface of the first outer tube  110 , namely attached to a region between the opening  101  and the internal thread  112 , and the connecting surface  224  may be fixed with the inner surface of the first outer tube  110  via laser welding, high frequency bonding, binder, etc. 
     Accordingly, the driving unit  130  of the electric support rod of this disclosure may be pre-assembled to the first outer tube  110 , the telescopic set  240 , the transmission screw rod  230  and the bearing  300  may be pre-assembled to the second outer tube  210 , and then the first outer tube  110  may be engaged with the second outer tube  210  so as to link the transmission screw rod  230  with the driving unit  130 . The second outer tube  210  has elastic arms  220 , the elastic arm  220  has the hook portion  223  and the outer thread structure  222  respectively disposed at inside and outside thereof, the bearing  300  may be fixed by the hook portion  223  when move into the second outer tube  210  so as to avoid loosening for a convenience of engaging the second outer tube  210  with the first outer tube  110 . Moreover, the second outer tube  210  is engaged with the first outer tube  110 , and then the elastic arm  220  is positioned by the inner surface of the first outer tube  110  so as to tightly fit the outer edge of the bearing. 
     While this disclosure has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of this disclosure set forth in the claims.