Collapsible and slidable cart

The collapsible and slidable cart provides for the transport of articles on both horizontal and oblique surfaces. The cart includes a pair of spacially parallel support members, each having a handle portion at the upper end and a wheel mounted for rotation at the lower end. At least one tray member for supporting articles extends outwardly from and is rotationally connected to the support members. Lock means which permit or prevent the rotational movement of the parallel support members relative to the tray member provides the cart user with means to collapse the cart for storage. The parallel support members have a curved, outwardly extending lower end portion so that the wheels extend outwardly from the remaining upper length. The curved lower ends having a low friction contact surface permits the cart to be transported on oblique surfaces, such as stairs. Also provided is a light-weight tubular cart construction which permits tray/support member rotation, as well as a hinged, tray perimeter member which permits the cart to be collapsed into a second configuration. Additionally, handle portion, curved lower portion, tray member, brace member, pouch member, elastic member, brake member, and hinged leg elements or configurations are provided to further enhance the use and function of the collapsible and slidable cart.

This invention relates to a collapsible cart for transporting articles. 
Particularly, this invention relates to a light-weight, collapsible cart 
which has wheels for transporting articles on generally horizontal 
surfaces, which has low friction surfaces positioned to negotiate oblique 
surfaces, such as stairs, and which, optionally, provides a combination of 
collapsing or folding configurations. 
The increased necessity and popularity of multi-dwelling living, such as in 
apartment, townhouse, condominium and high-rise buildings, has made it 
increasingly more difficult for dwellers to transport articles, such as 
groceries, packages, containers, etc., to and from their living quarters. 
And, often times the remote location of parking facilities, or the 
required use of stairs and elevators, has made this transport of articles 
an even more difficult task. 
The decreased amount of storage space inherent in these multi-dwelling 
buildings, and the increasing use of smaller automobiles, which 
comparatively have smaller trunks and interior spaces, has further 
increased the need of a light-weight, easy to assemble, collapsible cart. 
Consequently, most standard or known carts used for article transport 
purposes are not well suited to meet these limitations and requirements. 
Several types of wheeled carts for transporting articles have been proposed 
or utilized in the past. However, most carts have been designed for 
specific uses, such as in grocery stores, for transporting luggage, heavy 
objects or other large, bulky materials. Consequently, these carts have 
been complex in design, bulky in construction, and expensive to 
manufacture. 
Still other types of wheeled carts are limited in utility, or are uncapable 
of being collapsed or folded for storage purposes. 
The collapsible and slidable carts of this invention overcome the problems, 
difficulties and shortcomings of those prior art devices discussed above. 
The collapsible nature of carts according to this invention permits a cart 
to be collapsed or folded in a relatively flat configuration for hanging 
storage in a closet, for example, or to be collapsed or folded into a 
shorter, compact, less flat configuration for placement into a trunk or 
into the interior of a compact automobile. Additionally, carts according 
to the teachings of this invention are simple in design, inexpensive to 
manufacture, and are quickly and easily assembled by a typical user. 
Further, the carts of this invention are of a light-weight construction to 
facilitate transport when not in use for article carrying purposes, and 
are provided with slidable surface elements to permit the transport of 
articles up and down oblique walkways, such as stairs, without causing 
damage to walkway surfaces, such as linoleum, wood, or carpeting. 
In summary, this invention provides a collapsible and slidable cart which 
has wheels, is light-weight in construction, and is designed for easy 
assembly, multi-storage options, and to transport articles over a variety 
of typically encountered terrain. The cart includes a pair of elongated, 
spacially parallel support members, each having a handle portion at the 
upper end and a wheel mounted for rotation at the lower end. At least one 
tray member extends outwardly from the pair of support members and is 
fixed for rotation to each of them. The tray member which can be rigid, is 
preferably constructed of an elongated, tubular perimeter member having a 
flexible article supporting surface attached thereto and spanning its area 
in a generally planar fashion so that articles, such as grocery bags and 
packages, can be supported and transported thereon. And, a locking means 
to secure the two parallel support members in a fixed, generally upright 
position with the tray member in a generally horizontal position 
therebetween, is also provided. 
The cart of this invention provides elongated, tubular support members 
which are formed at the handle end in a U or C-shaped configuration to 
facilitate user grasping comfort, and to provide a hanging element to 
permit the collapsed cart to be hung and stored in a closet, for example. 
Also provided by the invention is a tubular support member structure having 
a curved lower portion so that the wheel mounted therebelow extends 
forwardly of the remaining upper support member structure. This 
configuration facilitates the ability of the cart to be slid on the 
support member structure, above and without obstruction by the wheels, to 
negotiate such oblique surfaces as stairs. The curved surface of the 
support member and the surface thereabove is of a smooth, low friction 
nature, and, preferably, a structural element, such as nylon, teflon or 
other material having those characteristics is attached at that location 
on the support member. 
The invention additionally provides a locking means which is comprised of 
at least one brace member for extending between and for lockable fixation 
to the opposing, parallel support members. Thus, the brace members provide 
the user with means to secure the cart in a predetermined configuration, 
such as erected for use, or collapsed for storage or transport. The brace 
members additionally are preferably located above the tray member or 
members to provide a backrest, article support element. 
Also provided are tray members having formed, upwardly extending, perimeter 
member portions which provide a forward lip or edge to further secure the 
articles caried on the article supporting surface. Additionally, even 
though the mounting for rotation of the perimeter member ends to each 
support member permits the rotational collapse or folding of the cart, a 
hinged, intermediate forward portion of the perimeter member permits the 
collapse or folding of the cart in a more compact configuration. 
And, finally provided by the invention is an attachable pouch member to the 
upper rear portion of a cart to provide for the carrying of smaller 
articles, such as purses or packages. Also, a movable ground engaging leg 
mounted to the lower most tray member provides for upright standing 
support to the cart to facilitate its parking, loading and unloading. A 
wheel braking member, elongated elastic members disposed between the 
support members, and other elements are provided to further enhance the 
use and function of the collapsible and slidable cart of this invention.

Referring to FIG. 1, a collapsible and slidable cart 10 is shown as having 
elongated, formed, tubular support members 11 and 12. The support members 
11 and 12 are shown having a curved lower portion, at the end of which 
wheels 13 and 14 are mounted for rotation. The wheels 13 and 14 are 
standard, light-weight wheels having axles 17 and 18, which are secured to 
the ends of the support members 11 and 12 by means of the axle extending 
through, and being bolted to, the lower ends, for example. 
At the upper ends of the support members 11 and 12 are formed handle 
portions or members 15 and 16 for grasping by the user to facilitate the 
pulling or pushing of the cart 10. The handle members 15 and 16 are 
preferably of a C or U-shaped configuration so that the handle member can 
also be utilized for storage hanging purposes, as shown in FIG. 5 on bar 
44, for example. 
The cart 10 has at least one tray member extending generally outwardly in a 
forward direction from the two parallel support members 11 and 12. The 
cart shown in FIG. 1 has two such tray members 19 and 20, the upper and 
lower, respectively. The tray members 19 and 20, shown in FIG. 1, further 
have perimeter members 21 and 24 which are generally outwardly extending 
U-shaped members which define a generally planar area for article support. 
However, it should be noted that the frontal portions of the perimeter 
members extend upward, or perpendicular to the planar area, to provide a 
frontal edge for containing the articles onto the article support surfaces 
22 and 25. These support surfaces 22 and 25 are generally flexible in 
nature and are attached to and span the respective perimeter members 21 
and 24. It should also be noted that optionally, depending upon cart use 
and requirement, the support surfaces 22 and 25 can be rigid in nature, 
for example to support heavier objects or objects which are desired to be 
stationary. Additionally, FIG. 6 illustrates a tray member configuration 
which utilizes a perimeter member 54, which is flat, to receive a rigid 
basket 55 having a lip 56. The latter configuration will facilitate the 
transport of small articles, for example, and provides a removable basket 
for other use. 
The tray members 19 and 20 are mounted for rotation to the support members 
to provide collapsing means for the cart 10, as will be described. The 
mounting detail is illustrated in FIG. 5 with respect to perimeter member 
21 to support member 11. This mounting method can likewise be utilized for 
other tray member constructions. 
A plate 48 is fastened to support member 11 by means of rivets 49. And, a 
perpendicularly extending post 50 is attached to this plate 48. Further, a 
circumferential ring 51 extends into the post member 50. The tubular end 
of perimeter member 21 fits about post 50 and an internally extending ring 
52 matingly protrudes into the ring 51 for securing the perimeter member 
21 to the post 50, while permitting the rotation of the perimeter member 
21 about the post 50. It is this rotational motion which permits the cart 
to be collapsed. 
Additionally, hinge members 23 and 26 located at perimeter members 21 and 
24 permit the perimeter members themselves to collapse in an upward, 
vertical direction, as shown in FIG. 8. The first collapsing structure, 
mentioned above, is illustrated in FIG. 7. The collapsed or folded 
structure of FIG. 7 provides an elongated structure which is flat and best 
suited for closet hanging storage, as shown with respect to bar 44. The 
second collapsed or folded configuration, as shown in FIG. 8, is shorter 
in length and best suited for automobile trunk or interior compartment 
storage. It should be mentioned, however, that a cart according to this 
invention can be provided with either or both of these collapsing features 
so as to provide various collapsing or folding alternatives. 
The cart 10 additionally has locking means to fix the cart in an upright 
position, for example, by preventing the rotation of the perimeter member 
end relative to the post extending from the support member. One locking 
means structure is shown in the drawings as brace members 29 and 30 which 
are elongated rigid members that are lockable to support members 11 and 12 
by means of elements 42, 43 and 40, 41, respectively. These elements are 
threaded bolt structures which extend from the support members, for 
example, and which receive a lock washer/internally threaded knob 
structure to tighten the brace members subsequent to the placement of the 
bolt through a matching aperture. However, the locking means can consist 
of any known structure which would prevent the rotation of the tray member 
relative to the support members. 
Preferably, the brace member is positioned above each tray member so as to 
provide a back rest for articles placed on the respective tray member. The 
brace members also can be attached to the support structure in an 
X-configuration, and it is not necessary that each connective rotational 
point be lockable in nature as long as the cart 10 can be erected in a 
stable, upright manner. For example, only one side of the brace member may 
be lockable so that the brace member remains attached to one support 
member as the opposite threaded knob/washer structure is loosened or 
removed. 
Additionally, a pair of elastic chord members 27 and 28 are provided for 
use with the tray members 19 and 20 to engage articles, such as grocery 
bags, placed on the trays and to thereby further secure these articles. 
The chord members 27 and 28 can be slidably mounted to the respective 
support members for vertical motion thereon, or they can be attached to 
hooks attached to the support members. 
A removable pouch member 31 having an exterior surface 34 and a pair of 
outwardly extending, generally S-shaped members for engaging apertures 35 
and 36 of the support members 11 and 12, is shown in FIGS. 1 and 2. The 
pouch member is removable for cart collapsing purposes, and it is designed 
to carry purses, small packages, and the like. The S-shaped or attachment 
members 32 and 33 permit the pouch member 31 to be quickly mountable and 
removable from the cart 10. The exterior surface 34 can be either a rigid 
or flexible construction. However, with respect to the latter, an 
appropriate frame member (not shown) would be necessary, and the 
attachment members could, in that case, be the ends of that frame member. 
Also shown in FIG. 2, and extending downwardly from the lower tray member 
20 is a rotatable, leg support member 37. This leg support 37, attached to 
the perimeter member of the tray, provides cart 10 with a balancing leg to 
permit its upright standing for the loading and unloading of articles onto 
and from the tray members. The leg support member is preferably rotatable 
and lockable in two positions, fully extended and at rest against the 
bottom of the tray. Additionally, it is preferable to have one such leg 
support member on either outside corner pf the lower tray member. If one 
such member is utilized, however, it is prefered that it be located at a 
generally central outside position of the perimeter member so as to 
provide maximum stability to the upright cart. It is also possible, 
although not shown, to have a third wheel mounted for rotation at the 
frontal bottom portion of the lowermost tray member. 
Importantly, as shown in FIGS. 1, 2 and 4, a slidable surface 38 and 39 is 
provided at the lower portion of each support member 11 and 12. This 
smooth, low friction surface permits the cart to be negotiated on oblique 
surfaces, such as stairs, without causing damage to the stair surface, 
such as wood or carpeting material. The surfaces 38 and 39 can be either 
smooth exterior surfaces of the support members themselves, such as chrome 
plating or a teflon coating for example, or they can be separate nylon or 
other low friction synthetic structural elements that are attached to the 
interior, lower surface of the respective support members. In either case, 
the slidable surface should preferably extend from below the curved bottom 
portion of the support member and then upward. 
As indicated above, the cart 10 is preferably light-weight in construction, 
primarily for transport and handling purposes. The use of aluminum tubing, 
having a 3/4 inch diameter for use as the support members has been found 
suitable for one cart construction. Additionally, a flexible cloth 
material, nylon or other synthetic material, for use as tray and pouch 
covering material and structure has also been found suitable. 
Dimensionally, a cart being approximately 40 inches high and having a 
width of about 17 inches with trays about 12 inches deep, has been found 
adequate for most article transport purposes, for example the transport of 
grocery bags, having two bags per tray. However, obviously other uses for 
the cart would require dimensions and structural elements, as required. 
The wheels of cart 10 are preferably mounted to the exterior of the support 
members for stability, and they should preferably extend outwardly from 
the bottom curved portions to permit the cart to be slidable on members 38 
and 39 when negotiating stairs, or the like. 
As many changes are possible to the embodiments of this invention, 
utilizing the teachings thereof, the description above and the 
accompanying drawings, should be viewed in the illustrative and not in the 
limited sense.