Abstract:
Presented is a table with a pivotable table top that is mounted rotatably and lockably about an axis of rotation extending in a longitudinal direction. The table has a pivoting mechanism on a table frame in the upper region of two lateral table legs. The table can be folded out or folded between a horizontal use position and a storage position. A pivoting movement of the table top is achieved, while combining secure operation and simple handling. The pivoting mechanism includes at least one pair of inter-engaging, mutually complementary tooth portions that are arranged concentrically about the axis of rotation. The tooth portions can be moved apart relative to one another by at least the tooth depth in the direction of the axis of rotation in order to enable the pivoting movement. In each pair, one tooth portion is mounted fixedly in terms of rotation with respect to the table leg and the other tooth portion is mounted fixedly in terms of rotation with respect to the table top.

Description:
CROSS REFERENCE TO COPENDING APPLICATIONS 
     This application is a continuation of PCT application No. PCT/EP/2009/004891 filed on Jul. 7, 2009 that designates the United States and claims priority to German Patent application DE 10 2008 037 285.4 filed Aug. 11, 2008 by Daniel Korb, the contents of which are all herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a table with a hinged table top having a pivoting mechanism in the table frame. The table top rotates about a horizontal axis and is lockable in both a vertical storage position and a horizontal use position. 
     BACKGROUND OF THE INVENTION 
     A folding table is described in European Patent EP 1 308 109 B1 with a table top rotatable about a horizontal axis. The table top is mounted on a table frame so that it can be turned and folded between a horizontal use position and a substantially vertical storage position. The swivel mechanism is designed to simultaneously pivot the table top relative to two side legs. For enabling the pivotal movement on both sides of the table top, cross members are included. The combined pivotal movement of the table top and rotational movement of the legs with the swivel mechanism in EP 1 308 109 B1 is relatively complicated with a correspondingly large number of individual components. 
     Other tables with swivel table tops are described in JP 10211023, U.S. Pat. No. 6,845,723, WO 01/54538, WO 01/13762, DE 90 11 229, EP 1 159 887, DE 102 60 503 and DE 100 38 223. 
     SUMMARY OF THE INVENTION 
     Disclosed is a table having a simple construction with a secure, easy-to-use, multifunction folding and unfolding table top. 
     The pivot mechanism of the table includes a pair of interlocking, mutually complementary, concentrically arranged tooth sections that are laterally movable relative to each other by at least the depth of the teeth. The tooth sections move in the direction of the axis of rotation and allow the table top to pivot when not engaged. In each pair of tooth sections, one tooth section is rotationally stationary (secured or fixed) relative to the table leg while the other tooth section is rotationally stationary relative to the table top. The interlocking teeth sections produce a stable, free of play, table that may be pivoted into multiple positions relative to the legs by simply engaging and disengaging the tooth sections. 
     Apart from the folded and unfolded pivotal positions, the table may also be locked into intermediate positions. 
     The tooth sections are formed in rings that are capable of interlocking with each other at a plurality of angular rotations. 
     The swivel mechanism may include a defined pivot angle and swivel range that limit the pivot of the table top to between the horizontal use and vertical storage configurations. In an exemplary example, the pivot range is defined by a cylindrical path that extends a defined distance, such as 90 or 180 degrees around a circular member. A limiting mechanism travels within the cylindrical path and prevents further rotation of the table when the end of the path is reached. Well within the cylindrical path may be added a well to lock the limiting element at set locations and define the angles at which the table top may be locked, such as horizontal, vertical, and 45 degrees. 
     The table includes a longitudinal beam extending below the table top along the rotational axis. Extending from the beam are cross members which extend perpendicularly to the beam and are secured to the table top. 
     The low cost swivel mechanism is provided with a cylindrical section that is rotated when pivoting the table about the rotation axis, and a cylindrical spigot that is configured to be inserted into the cylinder section. The cylinder section slidably and rotatablely connects to the spigot. In one embodiment, the cylinder section is integrally formed as part of the longitudinal beam. The simple, sturdy construction is enhanced by a limiting element mounted on the cylinder section that extends parallel to the axis of rotation. The limiting element travels in a cylindric track or recess (that is curved about the axis of rotation) than includes wells at various locations that correspond to the table top being at predefined angles such as horizontal or vertical. The limiting element fits into the well to prevent the table from rotating when engaged within the well. 
     When the limiting element is within the cylindrical track, the teeth are disengaged from each other so that the table top may freely pivot, however when the limiting element is within a well, the teeth are engaged so that the table top is prevented from rotating. By adding additional wells in the cylindrical track, intermediate positions are possible for the pivoting table top. By increasing the depth of the recess so that the teeth may be engaged when the limiting element is within the recess, numerous rotational settings can be selected for the table top. For example, slightly oblique inclinations of the table top relative to the horizontal setting may be selected by a user. 
     The table may be constructed such that a spring acts to engage or disengage the teeth sections from each other. The spring may be arranged within a bearing piece and connected to a supporting member such as a cap or flange. For easy handling and safe operation of the swivel mechanism, the table include an actuating linkage that act to engage and disengage the locking teeth. In one embodiment, the linkage extends within the longitudinal beam of the table frame. 
     The table may be stacked with several other tables in their folded positions. The offset arrangement of the legs in the lateral direction allows the tables to be stacked in a tighter configuration than would otherwise be possible. The table legs may be formed with or without wheels for rolling the tables. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A through 1D  show perspective side views of two tables with tilting table tops (folding table) in the retracted or extended position of the table. In  FIGS. 1A and 1B , the longitudinal beam of the table is located under the middle of the table top while in  FIGS. 1C and 1D  the longitudinal beam is under the posterior region of the table top. 
         FIGS. 2A and 2B  show several nested tables with the pivoted table tops in a perspective side view. 
         FIG. 3  shows a perspective view of a table frame with a longitudinal beam, two cross members, two side legs and end caps. 
         FIGS. 4A through 4F  show back, plan view, perspective view and three detailed views of the table frame in  FIG. 3 . 
         FIGS. 5A through 5C  show the table frame of  FIG. 3  in a disassembled view and two detail views of the swing mechanism. 
         FIGS. 6A through 6E  show the table of  FIG. 1B  in a perspective view from below, from a narrow side view of the back, on the underside with a boom traverse view, inverse view, and in a further perspective view from below marked with the line rods. 
         FIGS. 7A through 7D  show plan, front, perspective, and narrow side views of the longitudinal beam and cross members attached to a draw-rod system. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1A and 1B  show a folding table  1  with a centrally disposed longitudinal beam  4  and a swivel table top  2 . In  FIG. 1A  the table is in a pivoted, substantially vertical pivot position (storage position) while in  FIG. 1B  the table is shown in the horizontal pivot position (use position). In  FIGS. 1C and 1D  a second variation of the table is shown where the longitudinal beam  4  is located in the rear of the table. The illustrated table top  2  is rectangular; however the table top may have a different geometry such as square, oval or round. The table top  2  is connected near its two shorter side edges at its base to cross-beams  5 . The cross-beams  5  are attached on one side to the table legs  3  through the longitudinal beam  4 . The longitudinal beam  4  may extend under the center of the table top, as shown in  FIGS. 1A and 1B , or maybe off-center near the rear of the table top as shown in  FIGS. 1C and 1D . The supporting point of the legs is laterally outside of the cross members  5 , but may still be below the table top  2 . The table legs  3  have a top section  3 . 1  that is at least as long as the pivoted state downward portion of the table top  2 . The table legs  3  can be equipped with T-leg or C-foot lower portions connected to rollers  3 . 3  that support leg portions having a variety of angles. The two part legs have upper vertical sections, which together form the top section  3 . 1  and short-transverse joints connected the vertical sections together. The top sections are perpendicular to the longitudinal beam  4  and in the depth direction of the cross member  5 . As shown in  FIG. 3 , the top sections may be at an offset angle to one another. As shown in the representation of the table  1  in  2 A and  2 B, the longitudinal displacement of the legs can provide advantages for stacking the tables as compared to tables with linearly aligned legs. In the illustrated example, the longitudinal displacement of the leg sections is preferably at least the width of a leg in order to facilitate stacking of the tables. As shown in  FIG. 3 , the table legs  3  are connected through shells  3 . 4  to the longitudinal beam  4 . The shells  3 . 4  are coupled to extension units that support them from the longitudinal beam  4 . The extension unit has a bearing piece  11  in the form of a circular cylindrical hollow profile section as shown in the exploded views of  FIGS. 5A and 5B . 
     The longitudinal beam  4  includes a circular cylindrical spigot  4 . 1  extending away from, but near to, the cross member  5 . The spigot  4 . 1  may be an integrally formed part of the longitudinal beam or it may be a separately formed unit that is inserted into the longitudinal beam  4 . 
     The outer diameter of the spigot  4 . 1  is adapted to the inner diameter of the hollow profile of the longitudinal beam  4  so that a stable fit results when the spigot  4 . 1  is within the hollow profile of the longitudinal beam  4 . The inner diameter of the bearing piece  11  is set to be comparable to the external diameter of the spigot  4 . 1  so that the bearing section  11  is on the spigot  4 . 1  slidably and concentrically mounted to rotate about the axis of rotation. In order for the table top  2  to be supported along with the cross members  5  and the longitudinal beam  4  relative to the bearing piece  11  about the axis of rotation, the outer diameter of the bearing piece  11  preferably corresponds approximately to the outside diameter of the longitudinal beam  4  and may have the same hollow profile. 
     As shown in  FIGS. 3 ,  4 A through  4 F and  5 A through  5 C the pivot mechanism  10  has a first set of teeth  15  on the bearing piece and a second set of teeth  17  on the spigot  4 . 1 . The two sets of teeth face each other and have interlocking tapered teeth, so that a stable table top is provided when they are engaged and moving apart the teeth is done without difficulty. 
     As shown in  FIG. 4F , the outer diameter of the bearing piece  11  near the first set of teeth  15  includes a recess  12 . 1  that extends approximately a quarter of the circumference of the bearing piece. The spigot  4 . 1  near the second set of teeth  17  includes a limiting element  16  structured to slide within the recess  12 . 1  of the spigot. The recess acts to limit the rotation of the table top when the limiting element  16  strikes either end of the recessed path. In the mechanism shown in  FIG. 4F , the recess extends a quarter of the way around the spigot so that the limiting element will strike the ends of the recess when the table top is roughly vertical and roughly horizontal. 
     As shown in  FIG. 5B , at two or more of the extreme positions of the table top (e.g., horizontal and vertical) the recess  12 . 1  includes wells  12 . 2  that engage with the limiting element  16  to further limit the rotation of the table top. The first set of teeth  15  circumscribe the bearing piece  11  (and the axis of rotation) and are concentric with the edge of the recess  12 . 1 . The teeth of the first set of teeth extend out from the bearing piece parallel to the axis of rotation towards the second set of teeth. The first set of teeth  15  may be disengaged from the second set of teeth in order to rotate the table top. 
     The rotating mechanism provides an easy and safe pivoting movement from one extreme position to another. When the table top final positions are reached (e.g., fully vertical and fully horizontal) the free end portion of the limiting element  16  laterally slides into the wells  12 . 2  of the recess. Alternatively, the wells may laterally slide to around the limiting element  16  when the final positions of the table are reached. Regardless of the arrangement, the recess is laterally and rotationally fixed relative to one set of teeth while the limiting element is laterally and rotationally fixed relative to the other set of teeth. Rotationally fixed (or secured) is herein defined to mean that the objects rotationally fixed have constant angular and radial relationship about the axis of rotation, as viewed perpendicular to the axis of rotation, when the table top is rotated. Rotationally fixed objects may be translated relative to each parallel to the axis of rotation. The wells are of sufficient depth to facilitate the first set of teeth  15  interlocking and engaging with the second set of teeth  17  so that the pivot mechanism is stable and secure. The non-well portions of the recess may lack sufficient depth to allow the teeth to interconnect. By preventing the teeth from interconnecting at the non-well portions, the recess acts to ensure a smooth rotational movement of the table top between predetermined positions. The wells  12 . 2  may be wider than the limiting element  16  by a tooth width in order to ensure that the first and second sets of teeth can interlock with each other when the limiting element is located within the well. For example, the working position of the table top  2  can be varied to the horizontal position, but larger accidental pivoting is prevented. Additional wells  12 . 2  in the recess  12 . 1  may be provided to allow a user to adjust the table top to stable intermediate positions such as at a 45 degree angle. In the illustrated embodiment, the outer ring  12  is firmly secured to the cylindrical outer surface of the bearing piece  11 , while the limiting element  16  is fixed on the longitudinal beam  4 . A reverse arrangement is contemplated where the outer ring  12  is located on the longitudinal beam  4  while the limiting element  16  is located on the bearing piece  11 . 
     Exploded views of the bearing piece  11  are shown in  FIGS. 5B and 5C . A helical compression spring  13  acts to axially hold the bearing piece  11  against the spigot  4 . 1 . The compression spring  13  is supported by a supporting part  14  such as an annular flange or a cap. The compression spring  13  acts upon the bearing piece  11  which in turn pushes the first set of teeth  15  towards the second set of teeth  17 . In order to disengage the teeth, a linkage  23  shown in  FIGS. 5A and 7A  through  7 D engages the bearing piece  11  through the supporting part  14  and laterally pushes the bearing piece so that the first set of teeth  15  disengages from the second set of teeth  17 . Alternatively, the spring may act to disengage the first set of teeth from the second set of teeth while the linkage acts to pull the two sets of teeth into engagement. 
     The linkage  23  extends through the interior of the bearing piece  11 , the spigot  4 . 1  and the longitudinal beam  4  to an operating mechanism  20 . As shown in  FIG. 5A , the operating mechanism includes a hand operating portion  21  that pivots along an arc-shaped guide  22 . The hand operating portion pivots around a point in the interior of the longitudinal beam  4  while coupled to a portion of the linkage  23 . By rotating the hand operating portion  21 , the linkage  23  is longitudinally moved through the longitudinal beam  4  to release the bearing section  11 . The first set of teeth  15  may be released from the second set of teeth  17  so that the table top may be rotated. When the hand operating portion  21  returns to its original position, the linkage laterally travels through the longitudinal beam  4  and the compression spring retracts to engage the first set of teeth with the second set of teeth. 
     As shown in the drawings, the swivel mechanism includes a first set of teeth  15  interlocking with a second set of teeth  17  and a limiting element  16  on both sides of the table  1 . The operating mechanism  20  has dual linkages  23  that include two individual rods coupled in the manner previously described. Thus both pivot mechanisms  10  are operated with only one operating mechanism  20  with the hand operating portion  21  so that only one hand is needed for operation. The operating mechanism  20  is designed so that it locks the engagement of the first tooth section  15  to the second tooth section  17 , on either side of the table  1 , against the force of the spring  13 . When the operating mechanism releases the bearing piece  11 , the first tooth section  15  is disengaged from the second tooth section  17 . 
     The end cap  6 , which is installed before attaching the table legs  3  to the pivot mechanism  10 , is installed on an end portion of the longitudinal beam  4  so that the end portion of the longitudinal beam is completely covered. Around the table legs  3 , the supporting shells  3 . 4  are secured to the bearing piece  11  by screws or welding. To facilitate installation of the end cap  6 , it has a shape adapted to fit into the supporting shells  3 . 4 . The front end of the end cap  6  is located below the table top  2  or may be flush with a narrow side of the table top.