Abstract:
A foldable bed has a joint, which has a main body, a block up and down movably fitted to the body, two supports pivoted to the body, and two plates; two rods of a frame of the bed are pivoted to the body; the block is biased to a lowermost position by a spring, and the bed can be folded only when the block is kept in a highest position; the supports will be made to engage the block by the rods immediately after the bed is stretched, thus preventing the block from moving to the highest position; the plates are co-movable with the rods, and can make the block kept in the highest position immediately after at least one rod part is folded; thus, after the block is moved to the highest position, the rods can be folded one after the other without having to operate the block twice.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a joint of a foldable bed for babies, more particularly one, which is structured in such a way that damage thereto is prevented owing to improper actions of the user in folding and stretching the bed, and that rod parts of a frame of the bed, which are connected with the joint, will be more steadily held in position.  
         [0003]     2. Brief Description of the Prior Art  
         [0004]     Referring to  FIG. 12 , the applicant in the present application was granted U.S. Pat. No. 6,202,229 B1 on Mar. 20, 2001, which disclosed “A Joint Of A Foldable Bed For Babies”. The joint includes: 
        a main body  1  having a curved top portion  13 , two side plates  11 ,  12  extending downwards from the curved top portion  13 , to which two adjacent ones of rod parts  4 ,  4  of a frame of a bed are pivoted at inward ends, and gaps  17  next to two ends of the curved top portion  13 ;     a pressing block  2  up and down movably held between the side plates  11 ,  12 ; the pressing block  2  having two engaging trenches  22  on two sides facing respective ones of two ends of the main body  1 ;     a spring  24  positioned between the top curved portion  13  and a top of the pressing block  2  for biasing the pressing block  2  downwards to a lowermost position; and     two supporting members  3 ,  3  held between the side plates  11 ,  12  and on two sides of the pressing block  2 , and pivoted to the side plates  11 ,  12 ; each supporting member  3  having an engaging bar  32  on a first end for engagement with a corresponding engaging trench  22  on the pressing block  2 ; each supporting member  3  having a curved portion  34  formed on a second end substantially in an opposite direction of the first end for supporting a respective one of the inward ends of the rod parts  4  on when the bed is in a stretched position; the supporting members  3  having elastic plate portions  33  above the engaging bars  32  thereof.        
 
         [0009]     Thus, the supporting members  3  will be tightly pressed on respective ones of the engaging trenches  22  at the engaging bars  32  thereof to prevent the pressing block  2  from moving as soon as the rod parts  4  are pressed against the curved portions  34  of the supporting members  3  at the inward ends thereof owing to gravity after the bed has been stretched as well as after the pressing block  2  has been biased to the lowermost position by means of the spring  24 , thus preventing the bed from folding.  
         [0010]     And, to fold the bed, first the main body  1  is slightly lifted such that the inwards ends of the rod parts  4  move to higher position to be away from the curved portions  34  of the supporting members  3 ; thus, the supporting members  3  will pivot automatically so as to be away from the engaging trenches  22  of the pressing block  2 , no longer stopping the pressing block  2  from moving up. Then, the pressing block  2  is manually pushed to a highest position such that the supporting members  3  are free to pivot. Finally, the rod parts  4  are angularly displaced relative to the main  1  body towards an upright position where the inward ends of the rod parts  9  are the lowermost; thus the bed is folded.  
         [0011]     The above joint of a foldable bed is found to have disadvantages as followings: 
    1. One of the rod parts  4  can still be left in the horizontal stretched position in folding the bed because of improper action of the user. And, the user has to first push the pressing block  2  to the highest position again before he pivots the left-horizontal rod part  4  to the upright position because the pressing block  2  has been biased to the lowermost position by the spring  24  immediately after the user stopped pushing it. However, the user usually forces this rod part  4  to change angular position relative to the main body  1  without first pushing the pressing block  2 . Consequently, the joint is damaged.     2. Although supporting members  3  are formed with the curved portions  34  for contacting the curved sides of the rod parts  4 , the inward ends of the rod parts  4  still can&#39;t contact the curved portions  34  closely, and there is space in between. Consequently, the rod parts  4  are not steady enough when the bed is in the stretched position.    
 
       SUMMARY  
       [0014]     It is a main object of the present invention to provide a joint of a foldable bed for babies to overcome the above disadvantages.  
         [0015]     The joint includes a main body, a pressing block, two supporting members, and two plate members. The main body, the pressing block, and the supporting members are basically the same as those of the prior joint, and the plate members are fitted on the main body, and formed with stopping bumps for making the supporting members keep the pressing block in the highest position as soon as at least one of the rod parts of the frame is angularly displaced to the upright folded position; thus, in case the user only successfully moves one of the rod parts, and leaves the other rod part in the horizontal position in his first action of folding the bed, the pressing block will still be kept in the highest position, and the latter rod part still can be easily pivoted towards the folded position without any obstacle, preventing damage to the present joint. Furthermore, the inward ends of the rod parts have plane bottom sides, and the supporting members have plane bearing sides for supporting the plane bottom sides on; thus, the rod parts are more steadily held in position when the bed is in the stretched position. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     The present invention will be better understood by referring to the accompanying drawings, wherein:  
         [0017]      FIG. 1  is an exploded perspective view of the joint of a foldable bed according to the present invention,  
         [0018]      FIG. 2  is a front view of the joint of the present invention,  
         [0019]      FIG. 3  is a top view of the joint of the present invention,  
         [0020]      FIG. 4  is a front view of the present joint, in folding action for the bed (step one),  
         [0021]      FIG. 5  is a front view of the present joint, in folding action for the bed (step two),  
         [0022]      FIG. 6  is a front view of the joint, after folding action of the bed,  
         [0023]      FIG. 7  is a side view of the joint, in folding action of the bed,  
         [0024]      FIG. 8  is a front view of the joint, when the bed is in partially folded position,  
         [0025]      FIG. 9  is a front view of the joint, while the pressing block is in the highest position after the bed is partially folded,  
         [0026]      FIG. 10  is a front view of the present joint, when the bed is being stretched,  
         [0027]      FIG. 11  is a side view of the present joint, when the bed is being stretched, and  
         [0028]      FIG. 12  is an exploded perspective view of the prior joint of a foldable bed as described in Background.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0029]     Referring to FIGS.  1  to  3 , a preferred embodiment of a joint of a foldable bed for babies includes a main body  5 , a pressing block  6 , two supporting members  7 , two plate members  8 , and two plug bodies  91 , and is connected with two adjacent ones of rod parts  9  of a frame of the foldable bed, which have radial pivotal holes  92  near to inward ends thereof for connection with the joint. Furthermore, each of the rod parts  9  has a plug body  91 , which is inserted in the inward end, and which has a plane contact bottom  911  outside the rod part  9 , and a through hole  912  aligned with the pivotal hole  92 .  
         [0030]     The main body  5  of the joint has a curved top portion  52 , and two substantially parallel and opposing side plates  51 , which extend downwards from the curved top portion  52 , and project beyond the curved top portion  52  at two ends thereof. The side plates  51  are formed with two pairs of fitting holes  511  along lower ends of middle lines thereof, two pairs of pivotal holes  512  equidistant to the middle lines, two pairs of pivotal holes  513  on upper corners, two fitting holes  514  under the pivotal holes  513  of a first one of the side plates  51 , two through holes  516  higher than the pivotal holes  512  on the first side plate  51 , and two through holes  515  higher than the through holes  516  on the first side plate  51 ; the through holes  516  are farther away from the middle line of the first side plate  51  than the pivotal holes  512 . The curved top portion  52  has a opening  522  on a middle thereof, two connecting holes  521  on two sides of the opening  522 , and a locating plate  523  fitted to the opening  522  and projecting downwards between the side plates  51 . Protecting plates  57  are secured on the top portion  52  by means of securing elements  56 , which are passed through the protecting plates  57  as well as the connecting holes  521 .  
         [0031]     The rod parts  9  of the frame are pivoted to the main body  5  by means of pivotal posts  55 , which are passed through the pivotal holes  513 ,  92  of the main body  5  and the rod parts  9 , and the through holes  912  of the plug bodies  91  such that the rod parts  9  can be angularly displaced relative to the main body  5  for the frame to change from a folded position, as shown in  FIG. 6 , and a stretched position, as shown in  FIG. 2 , and vice versa.  
         [0032]     The pressing block  6  has an upright slot  61  at a middle, two engaging trenches  62  facing opposite directions, two stopping protrusions  63  under respective ones of the engaging trenches  62 , two holding recesses (not numbered) above the stopping protrusions  63 , and a locating cavity  64  on a top side. The pressing block  6  is up and down movably held between the side plates  51  of the main body  5  by means of guide pins  53 , which are passed through the fitting holes  511  of the main body  5 , and the slot  61  of the block  6 ; thus, the engaging trenches  62  are directed towards respective ones of the inward ends of the rod parts  9 . In addition, a spring  65  is positioned on the locating cavity  64  at a lower end, and fitted to the locating plate  523  at an upper end for biasing the pressing block  6  downwards to a lowermost position.  
         [0033]     Each of the supporting members  7  has a pivotal hole  71 , an engaging bar  72  at a first end, an elastic plate portion  73 , and a bearing side  74  formed on a second end substantially in an opposite direction of the first end. The supporting members  7  are pivoted to the main body  5  by means of pivotal pins  54 , which are passed through the pivotal holes  512 , and the pivotal holes  71  thereof, so as to be beside the pressing block  6  with the engaging bar  72  facing a corresponding engaging trench  62 .  
         [0034]     Each of the plate members  8  has a through hole  81  at a first end, a contacting bump  82  on a first side of the first end, a locating bump  83  also on the first side of the first end, a recess  84  over a middle portion of the first side, a touching bump  85  on a second end of the first side, and a stopping bump  86  also on the second end of the first side; the plate members  86  are flexible because the middle portions thereof are thinner owing to the presence of the recesses  84 . The plate members  8  are positioned next to the outer side of the first side plate  51 , and are connected to respective ones of the pivotal posts  55  of the rod parts  9  at the through holes  81  thereof with the locating bumps  83  being passed into the fitting holes  514  of the first side plate  51 , the contacting bumps  82  being pressed against the first side plate  51 , and with the touching bumps  85 , and the stopping bumps  86  being respectively passed through the through holes  515 ,  515 , and  516 ,  516  of the first side plate  51 , as early mentioned. In addition, when the foldable bed is in the stretched position, the rod parts  9  will touch the corresponding touching bumps  85  such that the second ends of the plate members  8  are pushed outwards, and the stopping bumps  86  will retreat from the inner side of the first side plate  51  so as not to be obstacle to the supporting members  7  any longer. And, the plate members  8  are pressed against the first side plate  51  at the contacting bumps  82  thereof such that there is a small distance between the first ends of the plate members  8  and the first side plate  51 , and the second ends of the plate members  8  are tightly pressed against the first side plate  51  with the touching bumps  85 , and the stopping bumps  86  projecting beyond the inner side of the first side plate  51 .  
         [0035]     Thus, referring to  FIG. 2 , when the bed is in the stretched position, and the pressing block  6  in the lowermost position, the plane contact bottoms  911  of the plug bodies  91  will be pressed against the bearing sides  74  of the supporting members  7  at the inward ends thereof owing to gravity and tension of cloth portion of the bed, and the supporting members  7  stopped from turning by the pressing block  6  with the engaging bars  72  being fitted onto, and pressed against the engaging trenches  62 , and in turns, the pressing block  6  cannot be moved upwards, and the rod parts  9  are stopped from pivoting downwards on the pivotal posts  55  by the bearing sides  74  of the supporting members  7 ; thus, the bed is prevented from folding. When the bed is in the stretched position, the inward ends of both the rod parts  9  will be pressed against the touching bumps  85  of the plate members  8  such that the stopping bumps  86  and the touching bumps  85  are retreated from the inner side of the first side plate  51 , as shown in  FIG. 3 .  
         [0036]     To fold the bed, referring to  FIG. 4 , first the main body  5  is slightly lifted such that the plane contact bottoms  911  of the plug bodies  91  move to a higher position to be away from the bearing sides  73  of the supporting members  7  together with the inwards ends of the rod parts  9 . Consequently, the supporting members  7  pivot automatically so as to be away from the engaging trenches  62 , no longer stopping the pressing block  6  from moving up, as shown in  FIG. 4 . Then, the pressing block  6  is pushed upwards, which will be stopped from moving further up as soon as the stopping protrusions  63  thereof come into contact with the inward ends of the supporting members  7 , on which the engaging bars  72  are formed, and the pressing block  6  is kept in the highest position; thus, the inward ends of the supporting members  7  are held in the holding recesses of the pressing block  6 , and the supporting members  7  are free to pivot in such direction that the outward ends thereof, on which the bearing sides  74  are formed, move down. Then, the main body  5  is pressed so as to cause angular displacement of the rod parts  9  towards an upright position where the inward ends of the rod parts  9  are the lowermost; thus, the plug bodies  91  will make the outward ends of the supporting members  7  move down together with them; thus, the outward ends of the supporting members  7  are right under the stopping bumps  86 , and the inward ends of the supporting members  7  are right under those portions of the pressing block  6  that are formed with the engaging trenches  62 ; the stopping bumps  86  will project beyond the inner side of the first side plate  51  again after the rod parts  9  leave them. Consequently, the supporting members  7  are stopped from turning, and the pressing block  6  is kept in the highest position by means of the supporting members  7 , as shown in  FIGS. 6 and 7 .  
         [0037]     Therefore, in folding the bed, in case the user only successfully makes one of the rod parts  9  pass beyond the corresponding stopping bump  86 , and leaves the other rod part  9  in the horizontal stretched position in his first action, the pressing block  6  will still be kept in the highest position by one of the supporting members  7  that is related to the former one of the rod parts  9 . And, the latter one of the rod parts  9  still can be easily pivoted to the upright position without any obstacle. In other words, there is no possibility of damage to the joint that could be caused when the rod part  9  is forced to pivot to the upright position while being still locked with the joint.  
         [0038]     Referring to  FIG. 9 , when the user moves a first one of the rod parts  9  towards the horizontally stretched position after having made the first rod part  9  move to under the corresponding stopping bump  86 , the first rod part  9  will force the corresponding stopping bump  86  retreat from the inner side of the first side plate  51  of the main body  5 , and in turns, the stopping bump  86  doesn&#39;t stop the corresponding supporting member  7  any longer, and the supporting member  7  is free to pivot with the outward end thereof moving upwards. And, the pressing block  6  will be made to move down to the lowermost position by the spring  65  immediately, and the corresponding engaging bar  72  will be pressed against the engaging trench  62  of the pressing block  6  with the help of the plug body  91  of the first rod part  9 , which is pressed against the bearing side  74  at the plane contact bottom  911  thereof.  
         [0039]     To stretch the bed, referring to  FIGS. 2 and 10 , the user only has to lift the main body  5 ; while the main body  5  is being lifted, the rod parts  9  will pivot so as to make the stopping bumps  86  retreat from the inner side of the first side plate  51  such that the stopping bumps  86  won&#39;t stop the corresponding supporting members  7  any longer, and the supporting members  7  are free to pivot with the outward ends thereof moving upwards. And, the pressing block  6  will move down to the lowermost position immediately after the above actions, and the engaging bars  72  of the supporting members  7  will be tightly fitted onto the engaging trenches  62  with the help of the plug bodies  91  of the rod parts  9 , which are pressed against the bearing sides  74  at the plane contact bottoms  911 . Thus, the bed is stretched, and fixed in the stretched position.  
         [0040]     Furthermore, the plate members  8  can&#39;t turn on the main body  5  owing to the engagement of the locating bumps  83  with the fitting holes  514 , and in turns, unwanted angular displacement of the plate members  8  are prevented after assembly. And, the contact between the contacting bumps  82  and the first side plate  51  will not only make the second ends of the plate members  8  tightly pressed against the first side plate  51  normally, but also will prevent errors in connecting the pivotal posts  55  to the rod parts  9  as well as the main body  5 , allowing the rod parts  9  to be properly fitted to the main body  5 .  
         [0041]     From the above description, it can be easily understood that the present joint of a foldable bed for babies has advantages as followings: 
    1. The rod parts  9  have the plane contact bottom sides  911  at the inward ends, and the bearing sides  74  of the supporting members  8  are plane therefore the inward ends of the rod parts  9  can be steady on the supporting members  8  when the bed is in the stretched position.     2. Because of the stopping bumps  86  for the supporting members  7 , in case the user only successfully makes one of the rod parts  9  pass beyond the corresponding stopping bump  86 , and leaves the other rod part  9  in the horizontal position in his first action of folding the bed, the pressing block  6  will still be kept in the highest position by means of one of the supporting members  7  that is related to the former rod part  9 . Consequently, the latter rod part  9  still can be easily pivoted towards the folded position without any obstacle, and there won&#39;t be any possibility of damage caused to the present joint by the angular displacement of the latter rod part  9 .     3. In stretching the bed, the rod parts  9  will pivot on the main body  5  so as to make the stopping bumps  86  retreat from the inner side of the first side plate  51  automatically. Consequently, the supporting members  7  are free to pivot with the outward ends thereof moving upwards, and the pressing block  6  will be made to move down by the spring  65  immediately for keeping the bed in the stretched position together with the supporting members  7 .     4. When the bed is in the stretched position, the rod parts  9  will touch the corresponding touching bumps  85  to push the second ends of the plate members  8 . Thus, the stopping bumps  86  of the plate members  8  will retreat from the inner side of the first side plate  51  so as not to be the obstacle to the supporting members  7  any longer.