It is also a feature of the present invention that a brace piece 40 is provided between the mattress 11 and the box spring 12, having the same general shape as the lower horizontal portions 23 and 24 but spaced vertically thereabove and engaging the vertical portions 21 and 22 midway along the lengths thereof. Thus, the brace portion 40 comprises first and second arms 41 and 42, which may be formed of the same material as the rest of the guard but need not have a vinyl coating thereon. It is intended that the brace portions 40 be continuously adjustable vertically along the vertical portions 21 and 22, in order to be snugly fitted to the top of any box spring 12. For this purpose each 43 of the brace portion 40 is provided with a snap fitting 44. Each fitting 44 has a hook portion 45 arranged transversely of the plane of the brace portion 40 formed by the arms 41 and 42 thereof, for grasping one of the vertical portions 21 and 22. Each connector 44 also has an appreciable vertical width to help increase the rigidity of the mattress guard 20 as against bending of the vertical arms 21 and 22.
Also in accordance with the principles of the present invention, a second horizontal portion 30 is optionally connected between upper ends 31, 32 of the vertical portions 21, 22, respectively. The second horizontal portion 30 comprises first and second arm portions 33 and 34, which join together at a corner 35 adjacent the corner of the mattress 18, as shown in FIG. 2. The arms 33 and 34 strengthen the mattress guard 20 and provide additional bearing surface against the sides 19a of the mattress 11 by which the mattress 11 is retained in its position against horizontal slippage. Such additional surface is especially useful to constrain foam mattresses. The second horizontal portion 30 is preferably constructed of the same 1/4-inch metal tube or rod as the vertical portions 21 and 22 and the lower horizontal portion 23 and 24; in fact, the entire assembly 20 is preferably provided in one continuous piece.
The mattress guard 20 is preferably constructed from a steel rod or tube of approximately 1/4-inch in diameter and is coated with a vinyl plastic. The steel wire or rod has sufficient transverse rigidity to maintain the vertical portions 21 and 22 straight and in perpendicular relation to the horizontal arms 23 and 24. Thus, since the horizontal arms 23 and 24 are each constrained from rotating about the bends 25 by the underside of the box spring 21, the mattress 11 is constrained from sliding to the right in the orientation of FIG. 3 by the vertical portion 21 of the mattress guard 20. That is, the horizontal arm 23 acts as a lever to prevent rotational displacement of the upper part of the vertical portion 21. The vertical portions of the edge rails 13 and boards 14 and 15 prevent sideward movement of the lower parts of the portions 21 and 22. Since, as shown in FIG. 1, four mattress guards 20 are provided, the mattress 11 is thus prevented from moving in any of four directions with respect to the box spring 12.
Each of the mattress guards 20 principally comprises a pair of vertical portions 21, 22 and a pair of corresponding horizontal arms 23 and 24. The vertical portion 21 is attached to the first horizontal arm 23 at a right angle bend 25, as shown in FIG. 3. The portion 22 is similarly connected to the arm 24, and the arms 23 and 24 join at a right-angle intersection spaced inwardly from the sides 19b of the box spring. The mattress guard 20 is held in place by the capture of the horizontal arms 23 and 24 at the right angle bends 25 between a lower edge 26 of the box spring 12 and the bed rail 13 and between such edge 26 and any ledges 16 and 17 of the head board 14 and foot board 15. Each vertical portion 21 and 22 of the guard 20 is held closely to the sides 19b of the box spring by vertical portions of the edge rails 13, the head board 14, and the foot board 15 adjacent the horizontal support ledges.