Triple beam frame

A box spring assembly for use as a foundation for a bedding mattress has a triple beam frame. The frame has three layers of which the bottom layer consists of longitudinal side rails equally spaced from a center rail and connected at each end to a double thickness end rail consisting of a lower and upper board. The middle layer of the frame includes a number of transverse slats equally spaced between the upper board end rails positioned at each lengthwise end of the box spring assembly. The lower board end rails underlie the upper board end rails and are in the bottom plane of the frame. The top layer of the frame consists of longitudinal slats spaced atop the transverse slats and upper board end rails. The triple beam frame is constructed of metal, wood, or a combination thereof. Coil springs are secured to the longitudinal slats in the box spring assembly. The longitudinal slats provide additional support and resistance to bending or deformation at the foot and head end of the box spring assembly, particularly if the foot end of the bed is unsupported by the bed frame. The provision of the longitudinal slats in a third layer of the wooden frame also provides a higher profile for the box spring assembly.

BACKGROUND OF THE INVENTION 
This invention relates to bedding, and more particularly, to bedding 
foundations or so-called "box springs" for use in the support of bedding 
mattresses. 
The desirability of a firm and yet resilient surface for sleeping or 
reclining has generated many improvements in the structure of mattresses 
in order to provide such a surface. The underlying foundation unit, or 
so-called "box spring", also contributes significantly to the firmness and 
resiliency characteristics of the mattress sleeping surface. 
Conventionally, bedding foundations or box springs are formed with a wooden 
rectangular frame positioned at the bottom of the box spring. The wooden 
frame includes a series of cross rails or transverse slats extending 
laterally across the wooden frame. Coil springs are provided in the box 
spring and are secured at their lower ends to these transverse slats and 
the upper portion of the torsion spring supports the upper surface of the 
box spring. A pad is typically applied over the top of the coil springs 
and a fabric cover is placed over the padding to extend downwardly along 
the side of the box spring to be secured to the bottom wooden frame. The 
upper surface of the box spring typically includes a wire grid which 
underlies the pad and is secured to the top ends of the torsion springs. 
The box spring is typically supported in a bed either on the conventional 
bed frame or in a metal angle iron frame, or so-called Hollywood bed 
frame, to which a headboard is attached. The mattress is positioned atop 
the box spring to provide a sleeping or reclining surface. 
A problem associated with the typical box spring assemblies described 
hereinabove is the lack of support around the border regions of the 
foundation unit. Specifically, the common practice of sitting on the end 
of the bed results in the deformation of the mattress and underlying box 
spring which over time can result in an indentation or sagging of the 
mattress and box spring at the lengthwise end of the bed. This problem 
results from insufficient border support of the box spring assembly at the 
lengthwise end of the bed. 
A further problem of the box spring assemblies described hereinabove 
results from the use of the angle iron or Hollywood bed frame in 
combination with the box spring and mattress. Typically, the Hollywood bed 
frame is shorter in length than the box spring and mattress resulting in 
an overhang of the box spring at the foot end of the bed. The Hollywood 
bed frame offers inadequate end support to the box spring and mattress 
combination at the lengthwise end of the bed. The portion of the box 
spring and mattress overhanging the Hollywood bed frame is unsupported 
thereby resulting in increased wear and deformation of the mattress and 
box spring at the lengthwise end of the bed and a tendency for the box 
spring and mattress to tilt or tip when one applies pressure or sits on 
the end of the bed. 
SUMMARY OF THE INVENTION 
The principal objective of the present invention has been to provide a box 
spring assembly which offers added border edge support at the longitudinal 
end of the bed. 
A further objective of the invention has been to provide a box spring of 
increased height or profile which can be produced both economically and 
efficiently for use within the highly competitive bedding industry. 
A still further objective of the invention has been to provide a box spring 
of increased strength and rigidity which is still relatively lightweight 
and inexpensive. 
The objectives of the present invention have been obtained by a box spring 
assembly having a triple beam frame. A triple beam frame has three layers 
of frame members. The bottom layer consists of a generally rectangular 
wooden frame with a pair of spaced longitudinal end rails connected by a 
lower board in a double thickness end rail transversely oriented at each 
end of the end rails. A center support rail extends longitudinally and 
parallel to the side rails to provide additional support to the center 
portion of the box spring. 
The middle layer of the triple beam frame consists of an upper board of the 
pair of end rails extending laterally in the box spring. The upper board 
of each end rail rests atop the lower board of each end rail. Three 
equally spaced transverse slats extend laterally between the end rails in 
the middle layer of the triple beam frame atop the side rails. The 
transverse slats provide the required lateral support and stiffness for 
the box spring. In one presently preferred embodiment, the three equally 
spaced transverse slats are wood and in other presently preferred 
embodiments they are metal or composite channels. 
The upper most layer of the triple beam frame consists of eight spaced 
longitudinal wooden slats. The eight longitudinal slats are positioned 
atop of and perpendicular to the end rails and transverse slats of the 
frame. The advantages of the longitudinal slats within the frame of the 
box spring assembly include a stiffer box spring and to provide more 
support at each longitudinal end than previously known box spring frames. 
This border edge support at each end of the bed provides added resiliency 
and resistance to deformation when one sits on the end of the bed, as is a 
common practice. The added support at each lengthwise end of the box 
spring provided by the longitudinal slats increases the life of both the 
box spring and mattress by reducing the tendency for an indentation or 
sagging area to develop over time as a result of one sitting on the edge 
of the bed. 
Additionally, a third layer in the frame of the box spring increases the 
height or profile of the box spring assembly by approximately 
three-fourths of an inch. This increased profile is advantageous in the 
competitive bedding industry in that the consumer demand for higher 
profile box springs and mattresses has increased. 
Another advantage of the longitudinal slats in the upper layer of the frame 
in the box spring assembly of the present invention is the added support 
and resistance to bending at the lengthwise end of the box spring when 
supported on a Hollywood bed frame. Typically, a Hollywood bed frame is 
shorter than the box spring and mattress. Therefore, a portion of the box 
spring and mattress extends beyond the Hollywood bed frame, typically at 
the longitudinal foot end. The longitudinal slats of the triple beam frame 
provide increased support at the unsupported longitudinal end thereby 
enabling one to use a Hollywood bed frame without sacrificing the 
longitudinal end border support or risking the tipping or tilting of the 
bed.

DETAILED DESCRIPTION OF THE INVENTION 
Referring to FIG. 1, a triple beam frame 10 of a box spring assembly 12 is 
shown. The generally rectangular frame 10 is incorporated into the box 
spring assembly 12 as the bottom portion thereof to which a plurality of 
coil springs 14 are stapled, nailed, or otherwise secured to the top of 
the frame 10. A border edge wire 16 extends around the upper periphery of 
the box spring assembly 12 and is clamped or otherwise secured to the 
upper most portion of coil springs 14 on the outer edges of the frame 10. 
A plurality of interconnecting transverse and longitudinal wires 18,20 
join the top edges of the coil springs 14 on the interior of the box 
spring assembly 12. The transverse and longitudinal wires 18,20 of the box 
spring 12 are clamped, welded, or otherwise secured to the border edge 
wire 16. A pad or upholstered cover (not shown) is provided as the top of 
the box spring assembly 12 and extends downwardly from the upper portion 
of the box spring assembly 12 to be tacked or otherwise secured to the 
triple beam frame 10 at the bottom of the box spring assembly 12. 
The triple beam frame 10 and box spring assembly 12 is shown supported on a 
Hollywood-type bed frame 22 in FIG. 1. The bed frame 22 supports the 
triple beam frame 10 along each lateral edge thereof by a generally 
L-shaped angle iron channel 24. The bed frame 22 is supported near the 
foot end of the box spring 12 by a leg 26 secured on each side of the bed 
frame 22 to the angle iron channel 24. The bed frame 22 includes a 
headboard 28 which is positioned at the head end of the box spring 12. The 
headboard 28 includes a pair of headboard posts 30 to which the angle iron 
channels 24 are connected to support the bed frame 22 at the head end 
thereof. 
The triple beam frame 10 of the present invention is constructed in three 
layers. The bottom most layer of the frame 10 includes a pair of spaced 
generally parallel wooden side rails 32 extending lengthwise in the frame 
10 along each outermost lateral edge thereof. The outermost bottom edge of 
each side rail 32 is supported in the angle iron channel 24 of the bed 
frame 22 to thereby support the box spring assembly 12. In a presently 
preferred embodiment of the triple beam frame 10, each side rail 32 is 
constructed of a single wooden board, one-inch by three-inches in cross 
section. 
Extending between corresponding longitudinal ends of the side rails 32 and 
generally perpendicular thereto is a double thickness wooden end rail 34 
positioned at each longitudinal end of the bed frame 10. The end rail 34 
is preferably constructed of a lower board 35 in the bottom layer of the 
frame and underlying an upper board 37. Also included in the bottom layer 
of the triple beam frame 10 is a center support rail 36 extending 
longitudinally between the end rails 34 generally equal distance between 
the side rails 32. The center support rail 36 is parallel to the side 
rails 32 and perpendicular to the end rails 34 in the bottom layer of the 
triple beam frame 10 and is preferably constructed of a wooden board, one 
inch by two-inches in cross-section. 
The middle layer of the triple beam frame 10 includes end rail upper board 
37 extending transversely at each longitudinal end of the box spring 
assembly 12. Each end rail upper board 37 rests on the end rail lower 
board 35 but is longer to extend to each outside lateral edge of the frame 
10. Each end rail upper board 37 is preferably constructed of a single 
wooden board one- inch by three-inches in cross-section; whereas, each end 
rail lower board 35 is preferably constructed of a single wooden board 
one-inch by one and a quarter inch in cross-section. In a presently 
preferred embodiment of the triple beam frame 10, each end of the end rail 
upper board 37 and side rail 32 is rounded to a two and a half inch radius 
forming corners 40 of the box spring assembly 12. The corners 40 of the 
box spring 12 are preferably rounded to avoid any sharp points or edges 
which may puncture or tear the upholstery covering on the box spring 
assembly 12 or provide a source of injury to one who contacts the corner 
region of the box spring assembly. 
In a first embodiment of the triple beam frame 10 as shown in FIG. 1, three 
transverse wooden slats 42 extend laterally in the middle layer of the 
triple beam frame 10 and are equally spaced between the end rails 34. The 
transverse slats 42 provide the lateral support at the box spring assembly 
side edges and are each preferably constructed of a single wooden board 
one-inch by two-inches in cross-section. Each end of each transverse slat 
42 is offset, preferably three-eighths of an inch, from the outermost side 
edge of the side rail 32 underlying the transverse slat 42. The transverse 
slats 42 are positioned orthogonally to the side rails 32 and center 
support rail 36 and parallel to the end rails 34 and in the middle layer 
of the frame 10. 
The top layer of the triple beam frame 10 consists of eight spaced 
longitudinal slats 44 extending lengthwise in the frame 10 and positioned 
atop and perpendicular to the transverse slats 42 and end rails 34. Each 
longitudinal slat 44 is preferably constructed of a single one-inch by 
two-inch wooden board and each end of the cross slat 44 is offset, 
preferably three-eighths of an inch, from the outermost lengthwise edge of 
the underlying end rail upper board 37. The longitudinal slats 44 provide 
the additional lengthwise support to each end of the box spring assembly 
12. Specifically, the longitudinal slats 44 offer added support to a 
portion of the triple beam frame 10 at the foot end of the box spring 
assembly 12 extending beyond the foot end of the Hollywood bed frame 22. 
The added lengthwise support offered by the longitudinal slats 44 enables 
one to sit at the foot end of the bed without the deformation or bending 
associated with box springs having only lateral slats. Furthermore, the 
box spring and mattress combination including the longitudinal slats 44 
will be less likely to deflect or tip at the foot end unsupported by the 
Hollywood bed frame 22. 
The lower end of each coil spring 14 is nailed, stapled, or otherwise 
secured to the top face of the longitudinal slats 44. The frame members 10 
of the triple beam frame of the present invention are secured to one 
another as by nails, staples, screws or other conventional fasteners. 
A second preferred embodiment of the present invention is shown in FIG. 2. 
The triple beam frame 10 shown in FIG. 2 includes all of the same 
components and elements as the first embodiment shown in FIG. 1; however, 
metal channels have been included as the transverse slats 42a. The metal 
channel transverse slats 42a each have a generally planar upper surface 43 
with a downwardly depending rib 45 on each side edge of the upper surface 
43. A flange 47 is formed onto each rib 45 and the flanges 47, 47 on each 
transverse slat 42a form a pair of spaced generally planar lower surfaces 
49 on the transverse slat 42a. The metal transverse slats 42a provide 
added strength and rigidity to the frame 10 while offering a more 
lightweight frame and box spring relative to an all wooden frame. 
In another embodiment of the present invention, the transverse slats 42 or 
42a are manufactured from a composite material or from fibers embedded 
within a resin matrix. Composite transverse slats offer sufficient 
structural integrity and rigidity with a reduction in weight as compared 
to wooden slats. 
From the above disclosure of the general principals of the present 
invention and the preceding detailed description of preferred embodiments, 
those skilled in the art will readily comprehend the various modifications 
to which the present invention is susceptible. For example, the invention 
has been shown and described with reference to particular materials and 
number of slats and beams, but it is readily within the scope of this 
invention to vary from these materials or structure. Therefore, we desire 
to be limited only by the scope of the following claims and equivalents 
thereof: