Bumper assembly for a rolling cart

In a rolling cart assembly, a smooth bumper assembly is provided that minimizes the likelihood of trapping dirt, grime, or the like. Corner bumper members having a smooth, uncrimped outer surface are provided with integral stiffening members and internally secured nuts so that the corner bumper members may be secured to a support frame by fasteners that extend in an outwardly direction from the inside surface of the support frame. Since the nuts are completely enclosed by the corner bumper members, the outside surface thereof are smooth and unbroken. Stiffening members may be co-molded or otherwise suitably formed integrally with and interiorly of the corner bumper members. Longitudinally extending side and end bumper strips are formed with an opening therein in order to receive V-shaped stiffening members. The side and end bumper strips are also secured to the support frame by fasteners that extend in an outward direction from the inside surface of the support frame so that the outside surface of the side and end bumper strips are also smooth and unbroken.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to rolling carts or the like and more 
particularly to an improved bumper assembly therefor. 
2. Description of The Prior Art 
Rolling carts, of the type to which the present invention is directed, are 
frequently used in environments where sanitary requirements are of the 
highest order. For example, various types of rolling carts are used in 
hospitals for transporting medicines, linens, catheters, surgical and 
diagnostic tools, food, I.V. units, baskets and the like. Because of its 
environment, the rolling cart should be kept as clean as possible and 
should of course be susceptible to low cost maintenance procedures that 
will avoid or at least minimize the likelihood of contamination. The 
rolling carts must necessarily be highly mobile and are therefore provided 
with resilient bumpers to prevent damage of the contents of the truck and 
to prevent damaging walls and doors should the trucks be inadvertently 
mishandled. It has been found that one common source of contamination 
resides in the resilient bumper means since these bumper means, at least 
those which surround the lowermost support frame, are fairly close to 
ground level. 
Those working in the field have recognized the problem and have attempted 
to provide solutions therefor but they have been generally unsuccessful, 
at least to the extent of providing rolling cart bumper means having 
smooth and unbroken surface areas that are less likely to attract and 
retain contaminants. 
For example, one form of prior art utilized a length of a resilient 
material that was wrapped around and suitably secured to a support frame. 
It was found, however, particularly as a result of formation of the 
corners, that the resilient material would bunch up and would therefore 
present ridges or grooves that easily attracted contaminants and which 
were difficult to clean. Moreover, with this first type of prior art 
bumper there was the problem of the resilient material cracking at the 
corners, particularly after extended usage. The cracks in the corners, of 
course, would easily accommodate small particles of dirt which could then 
become packed in and therefore very difficult to clean. In addition, the 
cracked and worn corners of this first type of prior art bumper was 
unsightly. It should be further noted that where bumpers are adhesively 
secured, they are difficult to replace without considerable skill and 
special equipment. 
In order to overcome the problem inherent in the first form of prior art 
structure described hereinabove, molded side and end resilient bumper 
strips were provided in combination with molded, L-shaped corner bumper 
members. The molded bumper strips and the molded corner bumper members, 
represented by this second form of prior art were fastened to the support 
frame by means of threaded fasteners. In order to accommodate the shanks 
and heads of threaded fasteners, the prior art bumper strips and bumper 
corner members were suitably counterbored. While the molded corner bumper 
members did overcome the problem of cracking at the corners of the bumper 
assembly, still another problem was raised by the counterbored holes. 
Obviously, if the counterbored holes are to receive fasteners, both of the 
diameters of the counterbored holes must be larger than the head of the 
fastener and the shank of the fastener. This is to accommodate normal 
tolerances in both the molding operation of the corner bumper members and 
the normal tolerance variations found in fasteners. Because the two 
diameters in the counterbored holes must necessarily be oversized in order 
to permit easy insertion and removal of the fasteners, the resulting play 
of the fastener in its respective counterbored hold provided recesses that 
could very easily accommodate dirt particles. In addition, it will be 
readily apparent that it was extremely difficult to maintain the 
oversized, counterbored holes in a clean condition. 
A further problem inherent in the prior art molded corner bumper means also 
relates to the oversized holes that were required for the fasteners. 
Because the holes were oversized there would necessarily be some limited 
movement of the molded corner bumper means with respect to the support 
frame and to the adjacent side and end bumper strips and this too resulted 
in crevices that could easily accommodate dirt particles. In addition, if 
the fit of the corner bumper means with respect to the size and end bumper 
strips was sloppy, as was frequently necessitated by virtue of the 
oversize, counterbored holes, there would be some loss of aesthetic appeal 
as well. 
SUMMARY OF THE INVENTION 
The present invention overcomes the shortcomings inherent in the prior art 
by providing support means in the form of an open frame that is defined by 
pairs of elongated spaced apart side sections and end sections. The 
support frame is open and, for purposes which will be made evident from 
the following description, includes inside and outside peripheral 
surfaces. Pairs of resilient side bumper strips and end bumper strips are 
secured to the side and end sections of the support means by fasteners 
having heads which bear against the inside surface of each of the support 
means sections and which extend in a direction generally outwardly of the 
support means. The side and end bumper strips may be tubular and may be 
provided with generally V-shaped, elongated stiffening means internally 
thereof so that the fasteners may be threaded therein. Self-tapping 
fasteners may be used for this purpose. 
It should be noted that the side and end bumper strips have a length less 
than the length of the side and end sections of the support frame in order 
to accommodate molded resilient corner bumper means intermediate the 
adjacent ends of pair of side and end bumper strips. The molded corner 
bumper members are provided with integral, internal and non-rotatable nuts 
in order to receive fastener means that extend in an outward direction 
from the inside surface of the side and end frame section. In this manner, 
the need for counterbored holes from the outside surface, such as taught 
by the prior art, is obviated. 
In addition, the corner bumper members comprising the present invention may 
be provided with internal stiffening means in the form of an elongated 
generally L-shaped metal strip. The stiffening means in one embodiment of 
the present invention are provided with holes therethrough that are in 
alignment with the holes formed in the side and end frame sections of the 
support means in order to receive the shank of the fasteners that secure 
the corner bumper members to the side and end frame sections. In one 
illustrated embodiment of the present invention, the internal nuts are 
first welded or otherwise suitably secured to the stiffening member and 
are thus non-rotatably positioned. Therefore, the corner bumper members, 
as well as the side and end bumper strips, may be secured to the support 
means without the need for counterboring a large number of holes. 
In the first embodiment of the present invention, the stiffening member is 
totally encapsulated by the corner bumper members. That is, the ends of 
the stiffening means terminate inwardly of the end faces of the corner 
bumper means. In an alternative embodiment of the present invention, the 
opening in which the stiffening means is positioned is continuous from one 
end face of the corner bumper means to the other and the stiffening means 
terminate inwardly of the end faces of the corner bumper means in order to 
define recesses therein. The stiffening means utilized in connection with 
the side and end bumper sections may then be made to extend slightly 
beyond the side and end bumper sections in order to be accommodated in the 
recesses in the end faces of the corner bumper means. 
A further embodiment, which may be utilized with either of the 
above-mentioned two embodiments, is to provide a cavity in the ends of 
each corner bumper member to receive the ends of the side and end bumper 
sections therein. This feature provides a more sanitary condition as the 
butt joint between the corner bumper member and the bumper sections is now 
covered. Furthermore, the opening in these bumper sections and the 
recesses in the corner bumper member are more effectively sealed to 
prevent dirt, water and vermin from lodging therein. 
Regardless of whether or not the stiffening means in the side and end 
bumper sections extend into the recesses in the corner bumper means, it is 
desirable to utilize self-tapping screw for securing the side and end 
bumper strips to the side and end frame sections. In so doing, the 
self-tapping screws slightly distort the stiffening means and as the 
fasteners are threaded therein they tend to flatten out the stiffening 
means slightly. This construction provides excellent clamping means since 
the stiffening means has some inherent resiliency that tends to force the 
inside face of the side and end bumper strips against the outside face of 
the side and end sections of the support means. This construction further 
minimizes any unsightly and unsanitary gaps between the bumper strips and 
the support means. 
Accordingly, it is an object of the present invention to provide an 
improved rolling cart that is more readily maintained in a highly sanitary 
condition. 
It is another object of the present invention to provide a rolling cart, as 
described above, having an improved bumper assembly that may readily be 
maintained in a highly sanitary condition. 
It is a further object of the present invention to provide an improved 
bumper assembly for a rolling cart, as described above, wherein the 
outside surface of the bumper means is devoid of any openings or the like 
that may become contaminated. 
Yet another object of the present invention is to provide an improved 
bumper assembly for a rolling cart, as described above, wherein nuts are 
formed integrally during the molding of the corner bumper sections in 
order to permit the assembly of fasteners from the inside of the support 
frame. 
Still another object of the present invention is to provide an improved 
bumper assembly for a rolling cart, as described above, wherein stiffening 
means are included. 
An additional object of the present invention is to provide an improved 
bumper assembly for a rolling cart, as described above, wherein the need 
for preformed, counterbored holes is obviated.

In the various figures of the drawing, like reference characters designate 
like parts. 
DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to FIG. 1 of the drawings, there is shown an improved bumper 
assembly 10 comprising the present invention. The bumper assembly 10 
comprises a pair of spacedly opposed side sections 12 and a pair of 
spacedly opposed end sections 14. The side and end frame sections 12 and 
14 which are generally L-shaped may be made from any suitable material 
such as aluminmum or stainless steel and are each comprised of a 
horizontal portion 16 and a vertical portion 18. For purposes of this 
description, it should be noted that the vertical sections 18 each have an 
inner surface 20 and an outer face 22. 
A plurality of posts 24 extend upwardly from the ends of the side frame 
sections 12 in order to support the remaining portion of a rolling cart 
(not shown). In addition, a swivelable and rollable castor assembly 26 is 
secured, in any suitable manner, in each of the four corners defined by 
the side and end frame sections 12 and 14. A pair of spacedly opposed side 
bumper strips 28 and a pair of spacedly opposed end bumper strips 30, are 
secured, in a manner to be described more fully hereinafter, to the side 
and end sections 12 and 14 of the bumper assembly 10. It should be noted 
at this time that the side and end bumper strips 28 and 30 are shorter in 
length than the side and end sections 12 and 14, respectively, in order to 
accommodate between adjacent end faces thereof, a resilient, molded corner 
bumper member 32. 
Turning now to FIGS. 2,3 and 4, it will be seen that the bumper strips 28 
and 30, which may be made from a suitable resilient material such as 
natural or synthetic rubber, are each comprised of a flat inner face 34 
that abuts the outer face 22 of the vertical section 18 and a generously 
rounded outer face 36. The side and end bumper strips 28 and 30 are 
further provided with a longitudinal extending, rectangular opening 38. 
A generally V-shaped, resilient stiffening member 42 is positioned within 
the opening 38. Self-tapping screws 46 extend through openings 48 which 
are formed in the vertical wall 18. As the screws 46 pass through the 
openings 48, the screws 46 form a plurality of transverse openings 40 
through the inside face 34 of the bumper strips 28 and 30, and then from a 
plurality of longitudinally spaced apart openings 44 in the stiffening 
members 42 which are positioned within the bumper strips, as best shown in 
FIGS. 2 and 4. Washers 50 are utilized between the inner face 20 of the 
vertical sections 18 and the head of the screws 46. 
It will be appreciated that as the screws 46 pass through the openings 48, 
and are tapping the openings 40 and 44, there will be a tendency for the 
V-shaped resilient stiffening member 42 to flatten out and exert a force 
which urges the face 34 of the bumper strips 28 and 30 against the outer 
face 22 of the vertical wall 18. This construction assures that there will 
be no gaps for collecting dirt between the side and end frame sections 12 
and 14 and the side and end bumper strips 28 and 30. 
As shown best in FIG. 5, the corner bumper members 32 are generally 
L-shaped with the juncture of the two legs 52 and 54 thereof being 
somewhat thicker than the ends of the legs 52 and 54 as a result of each 
leg being tapered. Thus, a tangent line 56, when drawn to adjacent corner 
bumper members 32 on one side or one end of the rolling cart, will define 
a plane that is further outward than the outermost surface of either the 
side bumper strips 28 or the end bumper strips 30. In this manner, minimal 
contact will be permitted between the side and end bumper strips 28 and 30 
and any object such as a wall, a post, a door or the like. 
It will also be seen in FIG. 5 that a generally L-shaped stiffening member 
58 is provided within the corner bumper member 32 with the ends of the 
stiffening member 58 terminating inwardly of the end faces 60 and 62 of 
the legs 52 and 54, respectively. Thus, the stiffening member 58 is 
completely encapsulated within the corner bumper member 32. In addition, a 
plurality of nuts 64 are welded or otherwise suitably secured to the 
stiffening member 58 so that they too are encapsulated and are 
non-rotatable. The stiffening member 58 and the vertical section 18 are 
provided with aligned openings 66 and 68, respectively, in order to 
receive screws 70. Beneath the head of each screw 70 is positioned a 
washer 72. By means of the construction just discussed, a smooth corner 
bumper 32 having an unbroken outer surface is provided with the fastening 
means therefor being inserted from a position inside the bumper assembly 
10. Because there are no exposed recesses, the corner bumper means 32 of 
the present invention can be maintained in a more sanitary condition than 
the corner bumper members of the prior art. This structure shown in FIG. 5 
may be readily and inexpensively assembled with a minimum of skill and 
utilizing only conventional tools, thereby reducing the cost of assembly, 
maintenance and replacement. The corner bumper member 32 may also be made 
of any suitable resilient material such as natural or synthetic rubber. 
In contrast to the embodiment shown in FIG. 5, the alternative 
constructions of the present invention shown in FIGS. 6 and 7 provide a 
cavity 73 and a through hole 74 in the corner bumper member 32'. As best 
shown in FIG. 6, the side walls of the cavity 73 are U-shaped to receive 
the end of the side or end bumper strip 28 or 30 therein. The portion of 
the cavity 73 which is positioned adjacent to the vertical section 18 of 
the frame section is open to allow the end of the bumper strip to be 
positioned against the vertical section 18. A cavity 73 is provided at 
both ends of each corner bumper member. The inner back wall or end face 
60' of the cavity 73 may be flat with no opening therein similar to FIG. 
5, or may be provided with the through hole 74, as set forth below. Thus, 
the cavity 73 provides a more sanitary condition as the butt joint between 
the corner bumper member and the bumper sections is now covered. 
Furthermore, the openings in the bumper sections and the recesses in the 
corner bumper member are more effectively sealed to prevent dirt, water 
and vermin from lodging therein. 
The through hole 74, when provided in the end face 60', receives a 
stiffening member 76 which is similar to stiffening member 58. It will be 
noted in FIG. 7 that the stiffening member 76 terminates inwardly of the 
end faces 60'. The stiffening member 42' of the side or end bumper strip 
28 or 30 may then be made to extend longitudinally outwardly thereof in 
order to be received in the recess 78 at the open end of the through hole 
74 of the corner bumper member. One recess 78 is provided at the ends of 
each corner bumper member and serves with the cavity 73 to additionally 
key the side and end bumper strips 28 and 30 to the corner bumper members 
32' to thereby minimize any gap therebetween. 
As used hereinabove, with reference to the outer surface of the side and 
end bumper strips 38 and 30 as well as the corner bumper members 32 and 
32', the terms "smooth" and "unbroken" refer to a lack of crevices or 
recesses such as counterbores which are likely to collect dirt particles. 
Preferably, the outer surface of the side and end bumper strips 28 and 30 
as well as the corner bumper members 32 and 32' should be smooth as 
possible to minimize the collection of dirt particles. However, if 
desired, there may be a decorative surface pattern, providing of course 
that there are no recesses, cracks or the like that can entrap dirt 
particles. 
Numerous alterations of the structure herein disclosed will suggest 
themselves to those skilled in the art. However, it is to be understood 
that the present disclosure relates to a preferred embodiment of the 
invention which is for purposes of illustration only and is not to be 
construed as a limitation of the invention.