Bed covering retaining device

A retainer for a mattress cover such as a sheet has a central band made of a stiff, smooth material and elastic straps attached to opposite ends of the band. Openable and lockable fasteners are attached to the ends of the straps, each fastener having a pair of jaws. One end of a short length of cord is attached to the fastener, the other end being free. In use, the band extends under the mattress and the fasteners are clamped to opposite sides of the cover with the cord inside a bight or fold of the cover to provide an enlargement which can be securely gripped by the fastener.

FIELD OF THE INVENTION 
This invention relates to an improved device for holding a sheet or other 
bed covering securely in place on a mattress. 
BACKGROUND OF THE INVENTION 
When a sheet or similar covering is placed on a mattress, it tends to slide 
because mattresses are commonly finished with a rather slippery surface. A 
flat sheet, mattress cover or even a fitted sheet slides because of the 
low friction between it and the mattress and, when a person gets into the 
bed, the sheet is likely to be displaced. 
Various solutions have been proposed to solve this problem, including 
straps which extend beneath the mattress and engage marginal portions of 
the sheet. In principle, this is a sound solution, but its implementation 
has given rise to some problems which have not been adequately solved, 
particularly in the attachment between the ends of the strap and the 
sheet. It has been proposed, for example, to use a strap or belt which has 
snap members or similar fasteners at the ends and to then permanently 
attach mating snap members to the sheet itself. While this would seem to 
be workable, it has the disadvantages of requiring the purchaser to go 
through the process of attaching the snap fasteners to the sheets or else 
acquiring special sheets to accompany the strap, neither of which is a 
satisfactory solution. 
Other devices of this type have used more universal attachment means not 
requiring special sheets, but the attachment devices have involved 
grippers which, in order to engage the sheet securely enough, tend to tear 
the fabric of the sheet, thereby shortening its useful life. 
In addition, those strap devices proposed in the past have had limitations 
on their effectiveness and simplicity of installation because of the 
structural nature and the materials employed. 
SUMMARY OF THE INVENTION 
Accordingly, an object of the present invention is to provide a retaining 
belt or strap for holding a cover on a bed mattress which is simple to 
install and which has an improved arrangement for engaging and holding the 
cover at both ends of the strap. 
A further object is to provide a cover-retaining strap which is stiff 
throughout a major part of its length to facilitate installation and to 
improve its cover-retaining properties. 
Briefly described, the invention comprises an elongated device for holding 
a cover on a bed mattress or the like comprising an elongated band of 
stiff, substantially inelastic material having smooth surfaces and having 
a length less than a dimension of a mattress with which the device is to 
be used and first and second openable and closeable fasteners, each 
fastener having a pair of jaws openable to receive fabric and lockable in 
the closed position. First and second elastic straps at opposite ends of 
the band interconnect the fasteners and opposite ends of the band, each of 
the elastic straps being fixedly attached at one end to an end of the band 
and at the other end to one of the first and second fasteners. First and 
second lengths of cord are fixedly attached at one end to one end of said 
device, the other ends of the lengths of cord being unattached until the 
device is used. In use, the band is inserted under a mattress, the cords 
are placed in folds adjacent marginal portions of the cover on opposite 
sides of the mattress and the jaws of the fasteners are closed and locked 
over the folds and cords together, with each fold enclosing one cord, so 
that the cover is securely held thereby.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
In the following description, the use of the device of the present 
invention will be discussed in connection with holding a sheet on a 
mattress, but it will be recognized that the nature of the cover being 
held on the mattress is not important and that the it is contemplated that 
the device can be used to hold a mattress cover, blanket or any other 
cover with which it may be useful. 
FIG. 1 shows a typical mattress indicated generally at 10 resting on box 
springs 11, the mattress being covered with a bottom sheet 13. Marginal 
portions 15 and 16 of the sheet extend around opposite sides of the 
mattress and under the edges of the mattress between the mattress and the 
box springs and, in the absence of other assistance, are held under the 
mattress simply by whatever friction there might be between the sheet and 
the mattress and box springs. Because that friction is often low, the 
sheet can be released partly or entirely, allowing the part of the sheet 
on which one lies to become slack. 
To retain the sheet, a device in accordance with the invention, indicated 
generally at 18, extends under the mattress and is attached to marginal 
portions 15 and 16 of the sheet, holding it in place. Device 18 is shown 
extending transversely across the bed which is clearly one advantageous 
way in which it can be used. However, the device can also be used 
extending lengthwise, if desired, either alone or in conjunction with one 
extending across the mattress as shown; or two such devices can be used 
crossing each other, each extending from one corner of the bed to a 
diagonally opposite corner. In each case the structure is the same; only 
the length dimensions of portions of the device differ. 
Device 18 is shown in more detail in FIG. 2 and includes a central band 20 
which is made of a low-friction plastic such as a medium density 
polyethylene, although other materials could be used. It is important for 
band 20 to be bendable but rather stiff so that it can be pushed between 
the mattress and box springs from one side of the bed. For use with a 
standard double bed, band 20 is typically about 32.5 inches long, about 
1.5 inches wide and about 1/8 to 3/16 inches thick. First and second 
elastic straps 22 and 23 are fixedly attached to opposite ends of band 20 
by attachment means such as staples 24 and 25. 
Each strap 22, 23 in the embodiment shown is made of a length of elastic 
about 1 inch wide and about 12 inches long, doubled over to form a bight 
at the end farthest from the band. The elastic is of a type commonly 
available at stores dealing in fabrics and other materials for making 
clothing and the like. In the present embodiment, the elastic, doubled 
over to form a strap about 5 inches long when unstretched, can be 
elastically elongated to a maximum length of about 11 inches. Both of the 
cut ends of the elastic are preferably folded over adjacent the band to 
provide extra thickness for the staple, and each staple 24, 25 is a 
heavy-duty, wide staple which forms a substantially permanent attachment 
between the strap and band. 
When the strap is folded over as described above, the bight is passed 
through a wire loop 27 or 28 of one of two clips 30 and 31 which are 
provided to engage and grip the cover. The clips themselves, one of which 
is shown in more detail in FIGS. 3 and 4, are conventional in nature and 
are similar to clips sometimes used on men's suspenders, each having a 
main body 32 forming a lower jaw 33, side trunions 34 and a bracket 35 for 
holding loop 27 about which elastic strap 22 passes. An upper jaw 37 has 
rear tangs which extend through an opening in the rear of main body 32 and 
side members extending laterally between bracket 35 and side trunions 34, 
allowing the upper jaw to move relative to the lower jaw and keeping loop 
27 from escaping. A movable blade 38 is pivotally mounted in trunions 34 
and pivots between an open position shown in FIG. 3 and a closed position 
shown in FIG. 4. In the closed position, the jaws are locked in an 
"overbite" position capable of engaging fabric therebetween. The clip is 
opened by lifting blade 38, allowing the jaws to open. 
Of particular importance is the provision of a length of cord 40 at each 
clip. Cord 40 is preferably a Nylon compliant cord about 5" or 6 inches 
long and about 3/16 inch to 1/4 inch in diameter. One end of the cord is 
doubled upon itself through a side of wire loop 27 or 28 and fastened in 
that position by a retaining band 41 of material such as heat-shrinkable 
tubing or a hog ring, the other end being free when not in use. To realize 
the need for cord 40, one must recognize the fact that a clip such as clip 
30 or 31 used alone to grab an edge of the cover would have some 
difficulty holding on to the cover or, if a clip of sufficient clamping 
strength were used, it would have a tendency to tear the sheet when placed 
under tension which is the normal use for the device of the present 
invention. The jaws of such clips commonly are formed with serrations at 
the distal edges of the jaws which can either be so smooth as to be 
essentially ineffective or so pointed as to be damaging. 
The use of the cord overcomes this problem. By placing the cord inside a 
simple fold or bight of the edge of the sheet and then closing the jaws 
over the bight so that the cord is inside the jaws, as illustrated in FIG. 
4, a relatively large lump is formed inside the jaws which is 
substantially impossible to remove from the jaws by simply pulling on the 
cover, and yet the cover itself is not gripped directly by the jaws in 
such a way that tearing forces are applied thereto. The cover is thus 
firmly and securely held without damaging the cover or significantly 
shortening its useful life. Attaching the cord to the clip in the manner 
shown makes the cord available when needed and assures that it will not be 
lost between uses. 
As thus described, the total length of a retaining device in accordance 
with the invention, made for a standard double bed, is about 43 inches in 
its relaxed condition and is stretchable to a total length of about 55 
inches from the end of one clip to the end of the other. It is 
contemplated that the device of the invention would be shipped in a box 
with the band 20 coiled into a circle of about 6 inches or so in diameter. 
To install a device in accordance with the invention, one would remove the 
device from the box and straighten it by bending it in the opposite 
direction from its original coiling. Because of the rather stiff nature of 
the band 20, it tends to remain coiled after having been in that condition 
for some time, but can be straightened in a few minutes. The band is 
preferably labeled on one side to indicate which side should be uppermost 
for installation, that side being as shown in FIG. 2 with the lower jaws 
of the clips facing up. With the clips closed, the strap 22 and clip 30 at 
one end of the device is folded back over the band 20 as shown in FIG. 5 
and the end of the band is inserted between the mattress and box springs 
11 about half-way along the length of the mattress, leaving an inch or so 
visible at the near end. In the case of a platform bed which has no box 
spring unit, the band is inserted between the mattress and the supporting 
slats. 
The clip is then attached to the closest side of the sheet or other cover 
as illustrated in FIGS. 3, 4 and 6 by opening the clip 31, placing an inch 
or so of cord 40 inside the edge of the sheet, rolling the edge of the 
sheet around the cord, placing the sheet and cord inside the jaws of the 
clip and closing the clip. The near end is then grasped and pushed until 
it is as far under the mattress as one can reach, stretching strap 23. On 
the other side of the bed, the strap is grasped and pulled through (FIG. 
7) and clip 30 is then attached to the other side of the cover in the same 
manner as clip 31 was attached, again placing cord 40 inside the edge of 
the sheet. This completes the installation. It will be noted that the 
retainer device need not be removed when changing sheets. It is only 
necessary to open the clips, remove the old sheet, replace it with the new 
and re-attach the clips as described above. 
For use with a small, narrow mattress such as a crib mattress or the like 
which is very light and easily handled compared with a conventional 
double, queen or king size mattress, it may not be necessary to make the 
center part of the band with the stiff material as described above. 
Rather, the entire band can be made flexible or even elastic because the 
mattress is commonly covered with a sheet by simply lifting the entire 
mattress and turning it over to attach the device of the invention. Thus, 
having the ability to push the band between mattresses or under a mattress 
is not so important. However, the cords and clips at the end are extremely 
advantageous. 
While certain advantageous embodiments have been chosen to illustrate the 
invention, it will be understood by those skilled in the art that various 
changes and modifications can be made therein without departing from the 
scope of the invention as defined in the appended claims.