Patent Publication Number: US-6334400-B1

Title: Foldable table

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to table, and more particularly to a foldable table. 
     BACKGROUND OF THE INVENTION 
     The U. S. Pat. No. 5,357,872 discloses a foldable table comprising two table tops  12  which are supported by two support legs  54 . The support leg  54  of one of the two table tops  12  is provided with an inner tube  66  which is fastened by a fastening bolt  64 . The fastening bolt  64  is apt to complicate the fixation of the support legs  54 . The prior art foldable table is not securely constructed. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a foldable table free from the shortcomings of the prior art foldable table described above. 
     The foldable table of the present invention comprises two table tops, two support legs, two support frames, and one retaining member. The two support legs are fastened pivotally with the undersides of the table tops. The two support frames are mounted in the undersides of the table tops and are pivoted together to enable the table tops to swivel on the pivoting portions. The retaining member serves to locate the support frames at such time when the two table tops are unfolded. 
     The features and the advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of the present invention with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a side schematic view of the present invention in the unfolded state. 
     FIG. 2 shows a side schematic view of the present invention in the folded state. 
     FIG. 3 shows a bottom view of the present invention with the table tops thereof being unfolded and with the support legs thereof being folded. 
     FIG. 4 shows a sectional view taken along the direction indicated by a line  4 — 4  as shown in FIG.  1 . 
     FIG. 5 is similar to FIG. 4 for showing a schematic view of the present invention in the unlocked state. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIGS. 1-5, a foldable table embodied in the present invention comprises component parts, which are described hereinafter. 
     Two table tops  20  are made of a plastic material by injection molding and are provided with a top surface  21 . The table tops  20  are provided in the underside with a plurality of reinforcing ribs  22  which are interlaced. The table tops  20  are further provided in the same lateral part with a hand grip  23  fastened therewith. 
     Two support legs  30  are made of a metal tube and are joined together to form a rectangular frame which is provided in the short side with two fitting pieces  31 . These two fitting pieces  31  are fastened in the underside of the table tops such that the fitting pieces  31  are parallel to the short axis of the table top  20 , so as to enable the support legs  30  to turn the other short side on the pivoting side acting as a pivot toward the underside of the table top. The short side is retained by a retaining member  32 . A folding frame  33  is disposed between each support leg and the underside of the table top and is formed of three connection rods. Two of the connection rods  34  are pivoted at one end thereof with two long sides of the rectangular frame. The third connection rod  35  is pivoted at one end with the underside of the table top, and at other end thereof with other ends of the two connection rods  34  to form a Y-shaped folding frame which is provided at each pivoting point with a bolt  36  for fastening each pivoting point. 
     Four support frames  40  are mounted in the underside of the table tops  20  such that the support frames  40  are parallel to the longitudinal axis of the table tops  20 , and that the ends of the support frames corresponding to the table top are contiguous to each other and are linearly opposite to each other. 
     Two corresponding support frames are provided with one set of pivoting device  50 , which comprises the following parts. 
     A first pivoting plate  51  and a second pivoting member  52  are two pivoting plates which are fastened at two adjoining ends by soldering so as to enable the ends of the two pivoting members to join together. The two pivoting members are provided in the adjoining ends with a round pivoting portion  53 , an axial hole  54  located in the middle. These two pivoting members are pivoted together by the pivoting portions. The axial hole  54  is provided with a shaft bolt  55  to enable the two pivoting members to turn on the shaft bolt. One side of the first pivoting plate is provided with a long receiving slot  511  parallel to the axis of the support frame. The slot  511  extends to the adjoining end surface of the second pivoting member  52 . The other side of the first pivoting plate is provided with a long through hole  512  corresponding to the midsection of the long receiving slot and extending along the axial direction of the long receiving slot. The second pivoting member is provided with a retaining slot  521  corresponding to the connection place of the long receiving slot and extending along the longitudinal axis of the receiving slot. 
     A retaining member  60  is a long bar-shaped retaining slide block, which is disposed in the receiving slot  511  of the first pivoting plate and is capable of moving along the longitudinal axis of the receiving slot. One end of the retaining slide block is inserted into the retaining slot  521  of the second pivoting member, so as to retain the retaining slide block between the two second pivoting members. The retaining slide block is provided in other end with a protruded portion  61 . The retaining slide block is provided in one side with a threaded hole  62  corresponding to the through hole of the first pivoting plate. 
     A spring  70  is disposed in the receiving slot  511  of the first pivoting plate and urges between the slide block  60  and the bottom of the receiving slot. The protruded portion  61  of the slide block is inserted into the spring which is intended to force one end of the slide block to jut out of the first pivoting plate. 
     A wrenching member  80  is a dial rod which is provided at one end with a threaded section, which is engaged with the threaded hole  62  of the slide block  60  via the through hole  512  of the first pivoting plate  51 . 
     As shown in FIGS. 4 and 5, when the two table tops are unfolded, the two corresponding support frames  40  turn on the shaft bolt  55  to align, as shown in FIG.  4 . As the wrenching member  80  is wrenched inward, the slide block  60  is actuated to move to compress the spring  70  such that the projecting part of the slide block is temporarily retracted into the receiving slot  511  of the first pivoting plate until the adjoining ends of the second pivoting plate  52  and the first pivoting plate come in contact with each other. In the meantime, the projected end of the slide block is forced by the recovery force of the spring to be retained in the retaining slot  521  of the second pivoting plate. As a result, the slide block is retained between the two pivoting members so as to fix the pivoting members and the support frames at an angle of 180 degrees at the time when the two table tops are unfolded. In the process of folding the two table tops, the wrenching member  80  is first wrenched inward to cause the slide block  60  to retract again such that the projected end of the slide block is not jutted out of the first pivoting plate, and that the projected end compresses the spring. The slide block thus moves out of the retaining slot  521  of the second pivoting plate, thereby enabling the two pivoting plates and the support frames  40  to turn freely. The support frames can be thus turned to fold the table tops.