FIELD OF THE INVENTION
- BACKGROUND OF THE INVENTION
The invention relates to an infant playyard, and particularly to an infant playyard that has a folding joint located on its bed bottom.
An infant playyard generally should have sufficient space to allow an infant to play inside without feeling confined. As a large bed frame takes too much space, modern designs mainly focus on foldable playyards.
A foldable playyard basically has four walls and a bed bottom. It utilizes joints to facilitate folding. The rails on the four walls may be turned and folded in the middle to move closely to the foot posts of the bed frame. These techniques are known in the prior art. References can be found in U.S. Pat. Nos. 4,811,437 and 5,697,111.
However the known techniques generally have complex bed bottom mechanisms. For instance, some have a central hub located on the bed bottom to pivotally engage with six rods in a precise manner. When there is a need for folding, the central hub may be pulled upwards and the six rods may be pivotally turned to fold the bed bottom.
- SUMMARY OF THE INVENTION
The complex construction of the conventional techniques often result in higher production costs. Defects and operational problems also increase. The folding joints on the bed bottom usually have complicated forms and make mold fabrication very difficult. The pivotal axes of the rods are located very close to one another and are difficult to assemble manually. All this indicates that there is still room for improvement.
The primary object of the invention is to provide a foldable bed bottom structure for playyards that is simply constructed and easy to assemble.
According to the invention, the bed bottom structure includes a pair of tension bar sets and a folding joint. The folding joint has a pivotal connection seat to pivotally engage with a pair of middle bars of the tension bar set. The two tension bar sets thus may be connected to form a support plane for the bottom bed of the playyard. The folding joint has a trough with an opening pointing downwards. The folding joint may be pivotally engaged with the middle bars. A handle bar with a brake element located at one end thereof may be wedged in a gap formed between the two middle bars to fill the pivotal turning space in the gap so that the bed bottom structure may be prevented from folding. When pulling the handle bar, the brake element is moved away from the gap to allow the middle bars to turn pivotally and make the bed bottom structure returning to a folding condition. Hence by pulling the handle bar, the bed bottom structure may be folded easily.
According to another embodiment of the invention, the handle bar may be fastened to a pulling band, which may be passed through the slits between the bed bottom board and the mattress. Users may pull the pulling band from above the bed to move the handle bar to indirectly fold the bed bottom.
Furthermore, the pivotal connection seat of the folding joint may be extended downwards to make contact with the floor to provide firm support for the bed bottom weight.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings. The drawings are only to serve for reference and illustrative purpose, and are not intended to limit the scope of the invention.
FIG. 1 is a schematic side view of a foldable infant playyard with a built-in foldable frame, as disclosed in U.S. Pat. Nos. 4,811,437 and 5,697,111.
FIG. 2 is a schematic bottom view of the invention adopted to a bed bottom of a foldable infant playyard, with a pair of tension bar sets and a folding joint to form a support plane.
FIGS. 3A and 3B are fragmentary sectional views of the pivotal engaging relationship between the folding joint and a tension bar set, with the handle bar at the first position, and the brake element wedged between the middle bars to prevent the bed bottom from folding.
FIGS. 4A and 4B are fragmentary sectional views of the pivotal engaging relationship between the folding joint and a tension bar set, with the handle bar at the second position, and the brake element moved away between the middle bars to allow the bed bottom to fold.
FIG. 5 is a fragmentary perspective view of a folding joint and a tension bar set of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 6 is a perspective of another embodiment of a folding joint of the invention, with an extended support section to make contact with the floor for supporting the bed bottom weight.
Referring to FIG. 1, the invention aims to provide a foldable bed bottom adaptable for an infant playyard. The bed bottom structure of the invention is simply constructed and easy to assemble.
Referring to FIG. 2, the bed bottom structure of the invention includes a pair of tension bar sets 11 and a folding joint. The tension bar sets 11 are pivotally engaged with side rails of a bed frame 10. There are middle bars 30 in the center, which have respectively an axis to the side rails of the bed frame 10.
Referring to FIGS. 3 through 5, the folding joint consists of a pivotal connection seat 20 and a handle bar 21. The handle bar 21 has one end bent to form a brake element 22. The pivotal connection seat 20 has a trough 26 with an opening pointing downwards. The middle bars 30 are pivotally engaged with the pivotal connection seat 20 in the trough 26. By means of the pivotal connection seat 20, the middle bars 30 and the tension bar sets 11 may be engaged to form a support plane for the bed bottom. The handle bar 21 may be pivotally engaged with the pivotal connection seat 20 in a first and second position. When the handle bar 21 is set in the first position, as shown in FIG. 3, the brake element 22 on the handle bar 21 is wedged in the trough 26 between a gap formed by the two middle bars 30 such that the bed bottom is not allowed to fold. Referring to FIG. 4, when the handle bar 21 is moved and switched to the second position, the brake element 22 is moved away from the gap between the two middle bars 30, and the bed bottom may then be folded.
Referring to FIG. 3, in order to increase the bucking stability of the middle bars 30 and pivotal connection seat 20, and to enhance the braking effect, a bucking pad 31 may be mounted to the free end of the middle bar 30 to increase the contact length with the brake element 22. The bucking pad 31 may be made of a block element with a height equal to or greater than the diameter of the middle bar. To those skilled in the art, it is known that the bucking pad 31 is for extending the vertical contact length and may be integrally formed with the middle bar 30, or be made of various metals or engineering plastics, then wedged in or bonded to the end section of the middle bar 30.
In order to allow the middle bar 30 or bucking pad 31 to pivotally turn about a pivotal axis 32 in the trough 26 smoothly without interference, the trough 26 should have sufficient turning space. However, it is also important to maintain the desired amount of contact between the middle bar 30 and the pivotal connection seat 20. Therefore two ends of the trough 26 may be respectively formed with an extending flange 25. Thus, loading of the bed bottom may be transferred through the flange 25 to the middle bars 30, and through the pivotal axis 32 to the tension bar sets 11 to generate a reaction force to support the loading. In practice, the bed bottom is usually covered by a bed board and/or mattress.
The handle bar 21 may have an annular opening 24 for people to grasp the handle bar 21. Another alternative is to fasten a pulling band 40 to the handle bar 21, and pass the pulling band 40 through the bed bottom. When in use, users may pull the pulling band 40 from above the bed to trigger the handle bar 21 and move the brake element 22 away from the trough 26. The middle bars 30 (including the tension bar sets 11) may then be lifted to fold the bed bottom.
The pivotal connection seat 20 may be made of high strength materials such as metal to provide the required support for the weight of the bed bottom. This also can be achieved by another embodiment shown in FIG. 6. The bottom end of the pivotal connection seat 20 may be extended to form a support section 27, which can make contact with the floor to bear the weight of the bed bottom.
While the preferred embodiments of the invention have been set forth for the purpose of disclosure, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention.