US2275353A - Folding leg structure - Google Patents

Description

March 3,1942. G. J. ENGE RT 2,275,353

VFOLDINVG LEG STRUCTURE I Filed Dec. 29, 1939 Patented Mar. 3, 1942 UNITED STATES PATENT ()FFICE FOLDING LEG STRUCTURE.

George J. Engert, Spokane, Wash. Application December 29, 1939, Serial No. 311,664

5 Claims.

This invention relates to improved folding leg structure, which is more. particularly adapted for use with folding tables, chairs, carpenters folding trestles or horses, and benches.

As one of its principal objects, the invention seeks to provide folding leg structure which will be capable of being extended to form a rigid support and of being folded to rest in a relatively small space.

A further object of the invention is to provide folding leg structure employing an improved hinge having reinforcing means for bracing the supporting legs associated with the hinge.

A further object of the invention is to provide structure of this class employing improved braces which support the legs of a table or the like in a highly eificient manner.

As a further object, the invention seeks to provide folding leg structure wherein means are employed for permitting the spreading of the legs of the table or the like. to any desired width.

And a still further object of the invention is to provide folding leg structure wherein the braces employed serve to protect the legs and table against angular strain.

Other objects of the invention, not particularly pointed out hereinbefore, will become apparent during the course of the following description.

In the drawing:

Figure 1 is a perspective view of a carpenters trestle equipped with my improved folding leg structure,

Figure 2 is an enlarged detail bottom plan view of the folding leg structure shown in Figure 1 as it would appear in folded, or retracted, position,

Figure 3 is an enlarged detail perspective view of the improved hinge employed in conjunction with my folding leg structure,

Figure 4 is an enlarged detail sectional view on the line 4-4 of Figure 2 looking in the direction indicated by the arrows.

Referring now more particularly to the drawing, the numeral I indicates in general a trestle for a saw horse such as is used by carpenters, plumbers and other tradesmen. The saw horse I includes a body 2 which is of Wood or other suitable material.

In order to support the body 2 of the saw horse I above a floor or other surface, I employ my improved folding leg structure. Said structure includes leg assemblies 3 and 4-. The leg assemblies are identical in construction so that it is believed that a description of one will suffice for both. The leg assembly 3, for example, includes legs 5 and 6 which are formed of wood or other suitable material. The legs 5 and 6 are connected at their intermediate portions by a jackknife link I, said jackknife link having link elements 8 and 9 which are pivotally connected at their opposite end portions by a pivot bolt Ill. The element 9 is extended upwardly and laterally to define a stop I I for limiting the jackknife link to substantially one hundred and eighty degrees extension. At their corresponding upper ends, the legs 5 and 6 are pivotally connected to a swinging plate I2 which forms part of a hinge I3, by means of bolts I 4. The hinge I 3 is shown in detail in Figure 3 and, by referring to said figure, it will be seen that said hinge I3 includes, in addition to the swinging plate I2, a base plate I4 which is flat throughout the major portion of its area. Said base plate has a hinge loop I5 thereon, said hinge loop being formed by turning back the central portion of the plate from one end toward the intermediate portion of the plate. The hinge loop I5 pivotally receives a hinge pin I6 which also extends through hinge loops I .I on the plate I2. The hinge loop I5 defines extensions I5" and- I 5" which provide bearing surfaces for the hinge loops I1 so that said hinge loops I1 will not be permitted to come in contact with the surface of the body 2. It will now be understood how the plate I2 is connected to the plate I4 of the hinge I3. Openings I8 are formed through the plate I4 of the hinge and normally receive therethrough fastening devices for securing the hinge to the under surface of the body 2 at one end thereof.

The plate I4 is formed with a reinforcing rib I9, said rib .being located near one end of said plate and extending laterally thereof throughout its width. The rib I9 is formed by bending the plate I4 downwardly at right angles and then bending it back substantially upon itself and then again bending the plate laterally in the same plane with the body of said plate I 4. The rib I9 cooperates with the hinge loops I5 and I! to define a pocket 20 for the upper ends of the legs 5 and 6 when said legs are in extended position. It will be understood that, as seen in Figure 2, the legs may be swung with the plate I2 for positioning said legs in folded position. In folded position, the legs will lie substantially parallel to each other and within the area of the lower surface of the body 2, this being accomplished by shifting the jackknife link elements 8 and 9 upwardly and on the pivot bolt ID for folding said jackknife link I to the position shown in Figure 2.

For bracing the leg assemblies in extended position, I employ braces 2I and 22. The braces are identical so that it will not be necessary to keeper.

describe them separately. The brace 2|, for example, is formed of a single length of fiat sheet metal and includes arms 23 and 24 which are connected by a substantially circular loop or bight portion 25. The free ends of the arms 23 and 2d are connected, pivotally, to the inner surfaces of the legs and 6 between their mid portions and their upper ends so that the brace will be swingingly connected with respect to the said legs 5 and 6. Mounted on the under surface of the body2 is a keeper bracket 26 which includes an offset keeper housing 21. Fastening screws 28 are employed for securing the bracket in position. Mounted in the keeper housing and projecting downwardly and toward the center of the body 2 is a keeper 29, said keeper having a square head as which is contained within the housing and a shank 3| which is apertured near its lower end, at 32, to receive a cotter key 33.

It is believed that the construction of my improved leg structure may be clearly understood without further discussion but, in order to obviate the possibility of error, a brief description of its -use here follows. The base plate 14 is attached to the under side of the body and, of course, provides means for pivotally connecting the legs of the leg assemblies 3 and 4 to said body. The legs of the leg assembly 'areshiftable on the hinges to folded position, as shown in Figure 2, or to extended position, as shown in Figure 1. In extended position, the brace it is shifted for engaging the loop or bight portion 25 with the shank 3| of the keeper 29 and the cotter key 33 is passed through the opening 32 for preventing displacement of the loop 2 35 from the The brace 2| will be highly efiec'tive for bracing the legs in extended position.

Attention is particularly called to the fact that the rib [9 will serve to reinforce the plate It of the hinge I3 and will, at the same time,.p'rovide a brace for the upper and rear ends of the legs 5 and B, dueto the fact that the upper and rear edges of said legs engage the base of the rib. A firm mounting for the upper ends of the legs will be assured in spite of the fact that said upper ends of said legs are pivotally'mounted on the swinging plate 12.

Having thus described the invention, what is claimed as new is:

2. In folding leg structure, the combination with an element to be supported, a hinge having a base plate to be secured to the element to be supported, a swinging plate and means pivotally connecting the swinging plate to the base plate, said base plate having a reinforcing rib, legs for supporting the element to be supported, means pivotally connecting said legs to the swinging plate, said legs being shiftable from a folded position to an extended position, a brace carried by the legs, and means carried by the element to be supported and engageable with the brace for cooperating therewith for retaining the legs in an extended position.

In a folding leg structure, the combination with a body, means for supporting the body including a hinge having a plate secured to the under face of the body, a swinging plate pivotally connected to the first-mentioned plate, a pair of legs pivotally connected to the swinging plate, a brace carried by the legs and having arms and a loop, and a keeper carried by the body .and having an inclined shank, said legs being movable mom a folded position parallel to the body to an extended position at right angles to the body, said loop being engageable with the inclined shank of the keeper for retaining the legs in an extended position.

4. In a structure of the class described, in combination with a body, means for supporting the body above a surface and'including a pair of legs, means pivotallyconnecting the legs to the body, said legs being movable from a folded position parallel to the body to an extended position at right angles to the body, a brace for retaining said legs in extended position, said brace being formed from a single strand of flat sheet metal and including a pair of arms connected by a circular bight portion defining a loop, and a keeper on the body and having aincl'ined shan'k for engagement by the loop.

5. In a structure of the class described, the combination with a body, means for supporting the body above a surface including a pair of legs, means pivotally connecting the legs with the body, said legs'being movable from a folded position parallel to the body to the extended position at substantially right ang'les'there'to, a brace pivotally connected with the legs and having arms and a bight portion, and a keeper carried by the'bo'dy, said keeper having a hea'd a shank'and a housing, said shank being engageable with'the big'ht portion for retaining :the legs in an extended position.

GEORGE J. ENGERT.

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