Patent Publication Number: US-9848696-B2

Title: Electric table stand, coupling thereof, and electric table with electric table stand

Description:
TECHNICAL FIELD 
     The present invention relates to an electric table technology and, in particular, to an electric table stand, a coupling thereof, and an electric table with the electric table stand. 
     BACKGROUND 
     By applying an elevator to an electric table, the electric table can fit each user&#39;s stature individually and can be adjusted to a desired height as required, so that the user can use the electric table comfortably, and therefore there is a trend to develop the electric table with an elevating function. 
     A conventional electric table mainly includes a table stand and at least two support legs connected to the table stand. Each support leg has an elevator inside. When each support leg is fixed to the table plate, such a large size is disadvantageous to superpose and put away the electric tables, so it is inconvenient and costly to transport the tables. 
     In order to solve the above-mentioned problems such as inconvenience in transportation and high transportation fees, the industries employs a separation design on the support legs and the table stand. The support legs and the table stand are driven by a motor and a plurality of transmission shafts. The motor and the transmission shafts are connected by means of a coupling. The only one motor is used to drive each support leg to ascend or descend. However, it is necessary to align and adjust the transmission shafts and solve other problems during the assembly process. Therefore, after buying a batch of desks, the client has to send many technicians to assemble the support legs to a table plate. As a result, assembly is not cost-effective and should be improved. 
     SUMMARY 
     It is an object of the present invention to provide an electric table stand, a coupling thereof, and an electric table with the electric table stand. A support leg and a holder can be joined quickly, thus saving labor costs in assembly. 
     Accordingly, the present invention provides an electric table stand, comprising a holder, at least two support legs and a transmission apparatus. The support legs are detachably connected to two ends of the holder and parallel to each other. Each of the support legs includes a screw rod and a first transmission shaft driving the screw rod to rotate. The transmission apparatus is assembled in the holder. The transmission apparatus includes a motor, a second transmission shaft driven by the motor, and at least one coupling. The coupling includes a first joint connected to the first transmission shaft, a second joint connected to the second transmission shaft, and a flexible body. The flexible body flexibly pushes the second joint to be correspondingly connected to the first joint. 
     Accordingly, the present invention provides a coupling of an electric table stand, comprising a first joint, a second joint, and a flexible body flexibly pushing to connect the first joint to the second joint. 
     Accordingly, the present invention provides an electric table, comprising a table plate and an electric table stand. The electric table stand includes a holder, at least two support legs and a transmission apparatus. The holder is fixed to the table plate. Each of the support legs is detachably connected to two ends of the holder and parallel to each other. Each of the support legs includes a screw rod and a first transmission shaft driving the screw rod to rotate. The transmission apparatus is assembled in the holder. The transmission apparatus includes a motor, a second transmission shaft driven by the motor, and at least one coupling. The coupling includes a first joint connected to the first transmission shaft, a second joint connected to the second transmission shaft, and a flexible body. The flexible body flexibly pushes the second joint to be correspondingly connected to the first joint. 
     Furthermore, the coupling includes a hollow sleeve, an end portion of the hollow sleeve is received in the second joint, and the second transmission shaft is inserted in the hollow sleeve. 
     The present invention further provides the following effects. By utilizing the coupling disposed between the second transmission shaft and the first transmission shaft, it saves time in aligning and joining the shafts, and thus the holder and each support leg can be joined quickly. Each support leg has the same structure to allow shared use, thus reducing costs in spare parts, stock and stock management in manufacturing the support legs. The first joint is connected to the support leg, and the second joint and the flexible body are connected to the second transmission shaft, so the holder and each support leg can be separately stored and packaged, thus requiring less space in a cargo container and greatly reducing transportation costs. By utilizing the flexible body to push the shaft member to move axially, a second protruding concaved structure is directly engaged into a first protruding concaved structure to achieve automatic assembly, thereby reducing assembly time. In addition to that, there is a larger overlapping area, so stress is uniform, and consequently, noise and vibrations are also reduced. Since the hollow sleeve is engaged into a cylindrical member, when it is desired to assemble the table stand or adjust a length thereof, the hollow sleeve can move along with the cylindrical member simply by pulling the cylindrical member, so the hollow sleeve need not be adjusted individually, thus saving assembly steps and considerable time. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will become more fully understood from the detailed description, and the drawings given herein below is for illustration only, and thus does not limit the disclosure, wherein: 
         FIG. 1  is a perspective view illustrating an electric table stand of the present invention; 
         FIG. 2  is an exploded view illustrating the electric table stand of the present invention; 
         FIG. 3  is a perspective exploded view illustrating a coupling of the present invention; 
         FIG. 4  is a cross-sectional view illustrating the coupling before connection; 
         FIG. 5  is a cross-sectional view illustrating the coupling after connection; 
         FIG. 6  is a cross-sectional view illustrating that the joints of the coupling after they are connected; 
         FIG. 7  is a schematic view illustrating the electric table stand in use; 
         FIG. 8  is a perspective exploded view illustrating the coupling according to another embodiment of the present invention; 
         FIG. 9  is a cross-sectional view illustrating the coupling before connection according to still another embodiment of the present invention; 
         FIG. 10  is a cross-sectional view illustrating the electric table stand according to another embodiment of the present invention; 
         FIG. 11  is a perspective exploded view illustrating the coupling according to yet another embodiment of the present invention; 
         FIG. 12  is an assembled view illustrating the coupling according to the yet another embodiment of the present invention; and 
         FIG. 13  is an assembled cross-sectional view illustrating the coupling according to the yet another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Detailed descriptions and technical contents of the present invention are illustrated below in conjunction with the accompany drawings. However, it is to be understood that the descriptions and the accompany drawings disclosed herein are merely illustrative and exemplary and not intended to limit the scope of the present invention. 
     Referring to  FIGS. 1 and 2 , the present invention provides an electric table stand, a coupling thereof, and an electric table with the electric table stand. The electric table stand comprises a holder  10 , at least two support legs  20 ,  30 , and a transmission apparatus  40 . 
     The holder  10  is provided to place a table plate  8 . The holder  10  includes a lateral rack  11  and two side wings  12 . The lateral rack  11  includes two rectangular tubes  111  arranged in juxtaposed and spaced apart relation and includes an accommodating recess  112  between the rectangular tubes  111 . The two side wings  12  are connected to a front end and a tail end of the lateral rack  11 , respectively, so that the holder  10  is substantially in an I-shaped configuration. 
     The support legs  20 ,  30  are detachably connected to two ends of the holder  10  and are parallel to each other. The support legs  20 ,  30  can be fixed by means of screw bolts or other fastening elements. The support leg  20  includes a screw rod  21 , a first transmission shaft  22 , a bevel gear set  23 , and a plurality of telescopic tubes  24 . The telescopic tubes  24  are nested one within another, and by means of connection, the screw rod  21  drives relative movement between the telescopic tubes  24  (as shown in  FIG. 7 ). The bevel gear set  23  includes a first gear  231  connected to a top end of the screw rod  21 , and includes a second gear  232  connected to one end of the first transmission shaft  22 . The gears  231 ,  232  can be bevel gears, helical gears and etc. The first gear  231  and the second gear  232  engagedly drive each other. The first transmission shaft  22  can has a regular hexagonal cross-section. 
     The other support leg  30  has the same structure as the foregoing support leg  20 , so any repetitive detailed description thereof is omitted. This configuration enables shared use of components and greatly reduces costs in spare parts, stock and stock management in manufacturing the support legs  20 ,  30 . 
     The transmission apparatus  40  is assembled in the holder  10 . The transmission apparatus  40  includes a motor  41 , a second transmission shaft  42  and a coupling  43 . The motor  41  is hidden, received and fixed in the accommodating recess  112 . The second transmission shaft  42  is parallel to each of the rectangular tubes  111  and is disposed at one side of the motor  41 . The motor  41  drives the second transmission shaft  42  to rotate by means of a gear set (not illustrated). 
     Referring to  FIGS. 3 and 4 , after assembly, the coupling  43  of the present embodiment substantially has an egg shape. The coupling  43  includes a first joint  431 , a second joint  436  and a flexible body  440 . The first joint  431  has a half housing  432 . A through hole  433  is formed at a center of the half housing  432 , and the through hole  433  has a shape corresponding to the shape of the first transmission shaft  22 , thereby facilitating insertion and connection of the first transmission shaft  22  with the half housing  432 . A first protruding concaved structure  434  and an internal thread  435  are disposed at one side inside the half housing  432 . 
     The second joint  436  includes a shaft member  437  and a half-housing member  438 . The shaft member  437  includes a shaft rod section  4371  and a joint section  4372  extending outwardly from one end of the shaft rod section  4371 . An axial hole  4373  passing through the shaft rod section  4371  and the joint section  4372  is disposed at a center of the shaft member  437 , and the axial hole  4373  is provided for insertion of the second transmission shaft  42 . An end portion of the joint section  4372  includes a second protruding concaved structure  4374  corresponding to the first protruding concaved structure  434  for engagement with the each other. The shaft rod section  4371  is connected to a fastener  439  at one side of the shaft rod section  4371  away from the joint section  4372 . 
     An external thread  4381  is disposed at one side of the half-housing member  438  for threadedly fastened to the internal thread  435 . The half-housing member  438  externally encloses the shaft member  437  and is blocked by the fastener  439 . The flexible body  440  is a compression coil spring, and the flexible body  440  is enclosingly disposed at an outer circumferential surface of the shaft rod section  4371  and is flexibly disposed between the joint section  4372  and the half-housing member  438 . 
     Referring to  FIGS. 1, 2, 5, and 6 , the first joint  431  is connected to the support leg  20  by means of a fastening ring, thereby achieving individual packaging and storage. The second joint  436  and the flexible body  440  are connected to the second transmission shaft  42 , thereby facilitating individual packaging and storage. When assembling, the support legs  20 ,  30  are assembled to the holder  10  first, and then the external thread  4381  of the half-housing member  438  is threadedly fastened to the internal thread  435  of the half housing  432 . At this point, the shaft member  437  is pushed toward the first protruding concaved structure  434  by an elastic force of the flexible body  440 , so that an end face of the second protruding concaved structure  4374  is in contact with an end face of the first protruding concaved structure  434  (see  FIG. 5 ), but at this moment the second protruding concaved structure  4374  is not assembled to the first protruding concaved structure  434  since the half-housing member  438  is hindered by the first joint  431  and is immobile along with the first joint  431 . 
     When the motor  41  is powered on to rotate, the motor  41  drives the second transmission shaft  42  to rotate and at the same time drives the shaft member  437  to rotate. The shaft member  437  is pushed toward the first protruding concaved structure  434  by the elastic force of the flexible body  440 , and therefore, upon rotation of the shaft member  437 , the second protruding concaved structure  4374  is aligned with the first protruding concaved structure  434 . Then, because the flexible body  440  pushes the shaft member  437  to move axially, the second protruding concaved structure  4374  is directly engaged into the first protruding concaved structure  434  to achieve automatic assembly. 
     Referring to  FIG. 7 , the present invention can include two couplings  43 , just like the present embodiment, or can include only one coupling  43 . The second transmission shaft  42  can include a hollow sleeve formed in a middle area and also include a hexagonal rod body connected to two ends of the hollow sleeve, as in the present embodiment, or alternatively the second transmission shaft  42  can be in a form of the hollow sleeve only or can be in a form of the hexagonal rod body. The motor  41  drives the second transmission shaft  42  to rotate, and each coupling  43  is connected to the second transmission shaft  42  and the first transmission shaft  22  of each of the support legs  20 ,  30 , so the first transmission shaft  22  drives the bevel gear set  23  to make the screw rod  21  rotate, and thereby telescopic tubes  24  can extend or retract to adjust a height of the table plate  8 . 
     Referring to  FIG. 8 , the difference between the present embodiment and the previous embodiment is as follows. The coupling  43   a  of the present embodiment includes a first joint  431   a , a second joint  436   a  and a flexible body  440 . The first joint  431   a  also includes a half housing  432 . The half housing  432  includes the through hole  433  and the first protruding concaved structure  434  mentioned in the previous embodiment, and the half housing  432  further includes a plurality of guiding positioning structures  4311   a  disposed at the half housing  432 . The second joint  436   a  also includes a shaft member  437  and a half-housing member  438   a . A plurality of protruding pillars  4381   a  extend from an outer circumferential surface of the half-housing member  438   a , and each of the protruding pillars  4381   a  is correspondingly engaged with each of the guiding positioning structures  4311   a , and thereby the half-housing member  438   a  and the first joint  431   a  can be joined quickly. An outer circumferential surface of the half housing  432  includes a plurality of indentations  4312   a , and the outer circumferential surface of the half-housing member  438   a  includes a plurality of indentations  4382   a , thereby facilitating clamping and rotation during assembly. 
     Referring to  FIG. 9 , in this embodiment, a coupling  43   b  includes a first joint  431   b , a second joint  436   b  and a flexible body  440 . The first joint  431   b  only includes the through hole  433  and the first protruding concaved structure  434  of the foregoing embodiment. The second joint  436   b  only includes a shaft member  437 . The shaft member  437  includes a shaft rod section  4371  and a joint section  4372  extending outwardly from one end of the shaft rod section  4371 , an end portion of the joint section  4372  includes a second protruding concaved structure  4374  corresponding to the first protruding concaved structure  434 , the shaft member  437  receives the second transmission shaft  42  and is slidable at the second transmission shaft  42 , the second transmission shaft  42  is connected to a C-shaped fastening ring  421 , and the flexible body  440  is enclosingly disposed at an outer circumferential surface of the shaft rod section  4371  and is flexibly disposed between the joint section  4372  and the C-shaped fastening ring  421 . Therefore, the present embodiment has the same effects as the above-mentioned embodiments. 
     Referring to  FIG. 10 , besides the above-mentioned regarding the electric table stand of the present embodiment, alternatively, the second joint  436  of the coupling  43  can be connected to the first transmission shaft  22 , and the first joint  431  is connected to the second transmission shaft  42 . The flexible body  440  flexibly pushes the first joint  431  to be correspondingly connected to the second joint  436 . Namely, compared to the foregoing embodiment, the first transmission shaft, the second transmission shaft, the first joint, and the second joint are connected differently in an interchanged manner, which also falls within the protection scope of the present invention. 
     Referring to  FIGS. 11 to 13 , a coupling  43   c  of the present embodiment includes a first joint  431   c , a second joint  436   c , and a flexible body  440 . The first joint  431   c  includes a half housing  432 , a first protruding concaved structure  434  is disposed inside the half housing  432 , a plurality of guiding positioning structures  4311   c  are disposed at the half housing  432 , a flexible fastening ring  4312   c  is disposed at one side of the half housing  432  away from each guiding positioning structure  4311   c , and the flexible fastening ring  4312   c  has a C shape. The first transmission shaft  22 , besides having a regular hexagonal cross-section, can also have a plurality of gear rods  221  on its surface, and a positioning recess  222  is disposed between each gear rod  221 , as in the present embodiment. The half housing  432  includes a toothed hole  433   c  at its center for engagement with each of the gear rods  221 , and the flexible fastening ring  4312   c  is correspondingly engaged with the positioning recess  222 . 
     The second joint  436   c  includes a shaft member  437 , a cylindrical member  438   c , and a rod assembly  439   c . A plurality of bumps  4381   c  extend from an outer circumferential edge of the cylindrical member  438   c , each of the bumps  4381   c  is correspondingly engaged with each of the guiding positioning structures  4311   c  for achieving quick engagement of the cylindrical member  438   c  with the first joint  431   c . A plurality of flexible arms  4382   c  is disposed on one end of the cylindrical member  438   c  away from each of the bumps  4381   c , and the flexible arm  4382   c  has an L-shaped cross-section. The rod assembly  439   c  includes a rod body  4391   c  and a hollow sleeve  4392   c . The rod body  4391   c  has a regular hexagonal cross-section. The hollow sleeve  4392   c  includes a narrow section  4393   c  at a front end, and a rear end of the hollow sleeve  4392   c  is configured for insertion of the second transmission shaft  42  (not illustrated). 
     For assembling the second joint  436   c , the flexible body  440  receives the shaft member  437 , and both of them are disposed inside the cylindrical member  438   c , the fastener  439  is fastened to one end of the rod body  4391   c , the other end of the rod body  4391   c  is inserted into the shaft member  437  and protrudes out from a center of the cylindrical member  438   c . After that, the hollow sleeve  4392   c  correspondingly receives, by its central hole, a portion of the rod body  4391   c  protruding out of the cylindrical member  438   c , and the hollow sleeve  4392   c  is pressed into the cylindrical member  438   c  and is engaged therein, so that each flexible arm  4382   c  is engaged with the narrow section  4393   c  and positioned. At last, a fastening member (not illustrated) is assembled onto a rear end face of the rod body  4391   c , so as to fix and couple the rod body  4391   c  and the hollow sleeve  4392   c  together. 
     When assembling, first the gear rods  221  of the first transmission shaft  22  are engaged with the toothed hole  433   c  of the first joint  431   c , and the flexible fastening ring  4312   c  is correspondingly engaged with the positioning recess  222 . Then, the second transmission shaft  42  (not illustrated) is inserted into the central hole of the hollow sleeve  4392   c . When joining, each of the bumps  4381   c  of the cylindrical member  438   c  is correspondingly engaged with each of the guiding positioning structures  4311   c  and is positioned after rotated. At this point, the second protruding concaved structure  4374  (as shown in  FIG. 3 ) of the shaft member  437  is not coupled to the first protruding concaved structure  434 . After the motor  41  is powered on to rotate, the motor  41  drives the second transmission shaft  42  to rotate and at the same time drives the shaft member  437  to rotate. The shaft member  437  is pushed by the elastic force of the flexible body  440 , and therefore, upon rotation of the shaft member  437 , the shaft member  437  moves axially, and thereby the second protruding concaved structure  4374  of the shaft member  437  is engaged into the first protruding concaved structure  434  to achieve automatic assembly. 
     In summary, the electric table stand, the coupling thereof, and the electric table with the electric table stand of the present invention certainly can achieve anticipated objectives and solve the conventional defects. The present invention also has novelty and non-obviousness, so the present invention completely complies with the requirements of patentability. Therefore, a request to patent the present invention is filed pursuant to patent law. Examination is kindly requested, and allowance of the present application is solicited to protect the rights of the inventor.