Knock down cart construction
United States Patent 3910205

A knock down two-part shelf construction for carts with outer ends of the shelf overhanging the main frame to provide unobstructed shelf space for high standing objects, and means to interconnect the two shelf parts to carry the load of objects on the overhanging outer ends and to retain alignment of the connection.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
108/157.13, D06/675.1
International Classes:
A47B31/00; A47B47/02; (IPC1-7): A47B3/06
Field of Search:
108/101,111,114,92,64,99,112,113,153 248
View Patent Images:
US Patent References:
3656439TILTING TABLE1972-04-18Domin
3204905Table supporting structure1965-09-07Marban
3178198Serving cart1965-04-13Hamilton
2980480Domestic appliance1961-04-18Jacobs
2972506Bench furniture1961-02-21Haag
2605150Connected sectional table1952-07-29Cohen
1909223Folding stand1933-05-16Roos
1488319Serving table1924-03-25DeCanio

Primary Examiner:
Zugel, Francis K.
Attorney, Agent or Firm:
Gravely, Lieder & Woodruff
What is claimed is

1. In a knock down cart assembly, spaced apart leg frames each having vertical portions and upper cross members connecting said vertical portions, a first elongated shelf, means detachably connecting said leg frames to the opposite ends of said first shelf, a second shelf spaced from said first shelf and having a length greater than said first shelf, said second shelf being formed of two portions having inner ends mating in end-on abutment along a parting plane located between said leg frames and having skirts depending from margins beginning adjacent said mating ends, said skirts being formed with pairs of grooves which align with each other across said parting plane when said shelf portions are mated at said inner ends, shelf portion aligning and clamping means detachably engaged in said grooves and spanning said mated inner ends to retain said two portions in alignment, and means removably connecting each shelf portion to a leg frame, said last connecting means retaining said leg frames in spaced relation and supporting said second shelf such that its two portions extend outwardly beyond said first shelf and beyond said leg frames.

2. The cart assembly set forth in claim 1 wherein said two shelf portions and said first shelf are of lesser dimensional size than said leg frames, whereby said shelf portions, said first shelf and said leg frames fit into a common package sized for said leg frames.

3. The cart assembly set forth in claim 1 wherein said clamping means has spaced legs to seat in said pairs of grooves and retain said second shelf portions against angular misalignment, said spaced legs being angularly directed relative to each other to draw said two shelf portions into alignment.

4. The cart assembly set forth in claim 1 wherein each of said second shelf portions has a length substantially equal to the length of said first elongated shelf.


This invention related to a knock down cart construction in which the parts are arranged to be packaged in a condition for assembly by the purchaser.

The construction of knock down carts and similar articles is advantageous from the view point of packaging, handling and shipping. However, the problem is to make the parts in such a way that there is little chance for the purchaser to make mistakes in the final assembly or in making the parts fit securely so that the final article will support the load imposed thereon. Therefore, the size of the various components is critical to the packaging and shipping, and parts must be made to conform to that need without imposing assembly problems.

The objects of this invention are to provide a cart with a shelf component that furnishes a large area by uniting separate parts, to provide a large area shelf which can be knocked down to fit minimum package size, to provide means for interconnecting shelf parts to maintain matching alignment and carry the loads imposed thereon, and to simplify the establishment of the connection of two parts so that the purchaser will be able with simple tools to effect the assembly.

A preferred embodiment of this invention for a knock down cart construction includes leg frames, a first shelf connected to the leg frames and acting to hold the leg frames in spaced relation, a second shelf made up of separable parts to keep the size of the parts to a minimum but to extend the shelf area outwardly beyond the ends of the first shelf to accommodate tall objects, means connecting the separable parts of the second shelf to effect alignment and sustain the load of objects placed thereon, and means connecting the second shelf to the leg frames spaced from the first shelf so that the leg frames and shelves cooperate to produce a sturdy cart.

The embodiment herein disclosed is featured by keeping the shelf components within the size of the supporting leg frames to limit the package size, and is further featured by providing at least one shelf having an area exceeding the package size by subdividing the shelf into individual parts of less size than the leg frames.


The embodiment of this invention presently preferred is shown in the accompanying drawings, wherein:

FIG. 1 is a perspective view of a knock down cart but in its erected condition with portions broken away;

FIG. 2 is an end view of a shelf construction in its flat form and when folded in a final form to provide a skirt for the main shelf surface;

FIG. 3 is a fragmentary detail of the interconnection between two shelf parts, the view being taken at line 3--3 in FIG. 1;

FIG. 4 is a fragmentary section taken at line 4--4 in FIG. 3; and

FIG. 5 is an end view of the clamp bracket seen in FIGS. 3 and 4 and used on opposite sides of the shelf abutment.


FIG. 1 is a perspective view of the cart in its assembled condition. The cart includes leg frame members having vertical legs 10A provided with suitable casters 11 for rendering the cart movable, a top platform 12 detachably connected to the upper ends of the frame by tie rods 13 which extend between the front pair of legs 10A and between the rear pair of legs 10A, and an intermediate shelf member 14 supported by a set of tie rods 15 which are similar to tie rods 13. The upper ends of the leg frames 10 are interconnected by a cross member 10B which is integral with its legs and bent to a 90° position by mitering at the bend. The top platform 12 and intermediate shelf 14, together with the cooperating tie rods 13 and 15 respectively, hold the leg frames 10 in desired position.

In addition to the shelf 14, a lower extended shelf assembly 16 is incorporated and is comprised of a pair of shelf portions 16A which are identical in configuration and dimensions and together make up the complete shelf. The length of the separate shelf portions 16A is kept close to or within the length of the top platform 12, thereby enabling the components to be packaged in the unassembled or knock down condition in as small a carton as possible. Therefore, the size of the largest component, which in this example are the legs, will determine the carton size.

The shelf assembly 16 is unique in that it is made up of portions 16A that are not bigger than other components of the cart, but when erected or assembled for use the portions 16A extend outwardly of the intermediate shelf 14 and top platform 12 to provide wing surfaces for the reception of objects which stand higher than the elevation of the shelf 14. The shelf portions 16A are connected to the adjacent legs 10A by tie rods 17 which are parallel to the cross member 10A of the leg frames 10. The projection of the shelf portions 16A outwardly of the tie rods 17 and leg members 10A introduces the problem of counteracting the up load at the parting line and plane of abutment 18.

In FIGS. 2 to 5, the shelf 16 is formed from a sheet of wood, pressed wood or fiberboard, such as Masonite. The sheet is covered on one surface with a ply 19 of vinyl having a wood grain finish. The skirt 20 which boarders the shelf on three margins is formed by cutting grooves 21 through the wood sheet but not through the vinyl ply 19, thereby using the vinyl ply as the connective element. The grooves 21 are cut at 45° to the sheet portions so that when coated with glue and folded the skirt 20 will be at 90° to the surface of the shelf as shown in FIGS. 2 and 4. Before folding the skirt 20 into position, as in FIG. 2, the inner surface of the skirt is formed with two channel grooves 22 and 23 which extend the full length of the skirt 20, at least on the longitudinal sides of the shelf. The groove 23 is spaced inwardly from the free edge of the skirt 20 a distance that will provide a sufficient body of material to resist chipping or splitting.

The shelf portions 16A abut along the common parting plane 18 (FIG. 1) and must be properly aligned so that there will be no raised edge or misalignment evident when in assembled abutment. The means to gain and hold alignment is constituted of the channel grooves 22 and 23 formed in the inner surface of the skirt 20, and a clamping bracket 24 (FIGS. 3, 4 and 5) of metal formed into a channel with legs 25 turned or bent to the same side and to an angle of about 85°. The legs 25 are spaced apart to seat in the grooves 22 and 23 of the skirts 20 on the two abutting shelf portions 16A so as to span the abutment of parting plane 18 a sufficient distance to securely hold the shelf portions 16A in alignment with heavy objects on the extended ends. The angle of deviation of the legs 25 is provided to insure that the channel grooves 22 and 23 align as intended and thereby draw the shelf portions 16A into exterior surface alignment. Suitable threaded fastners 26 and nuts 27 are used to hold the brackets 24 in position.

It is, of course, understood that two brackets 24 are needed to join and align the skirts 20 between the shelf portions 16A and across the abutment plane 18. Also, the shelf 16 may be located above either shelf 12 or 14, but is best suited to be the lowest shelf with the portions 16A cantilevered by the rods 17 from the respective legs 10A.