US702431A - Foldable trestle. - Google Patents

Description

No.`702',43|. 4 Patented lune I7, |902. v H. E. HOWARD.

FBLDABLE TRESTLE.

(Application tiled Jag; 24, 1902.)

(No Modal.)

UNITED STATES PATENT OFFICE.

HARRXT E. HOWARD, OF CHICAGO, ILLINOIS.

FOLDABLE TRESTLE.

SPECIFICATION formingpart 0f Letters Patent N 0. 702,431, dated June 17, 1902.

Application filed January 24, 1902; Serial No. 91,009. l (No model.)

T0 @ZZ whom it' may concern: y

Be it known that I, HARRY E. HOWARD, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Foldable Trestles; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in that class of folding trestles thatis especially adapted for use by paper-hangers as supports for their paste boards, widening boards, square-edges, dac. though it is also susceptible of use as a trestle for other purposes when made larger and stronger.

The especial objects sought by my improvements are economy of construction, strength and rigidity, and compactness when folded. It is customary for paper-hangers to carry their trestles and paste-boards in their hands when going to and from work. Hence it is essential that the former should be made as light as possible, readily foldable into small space for convenience in carrying, and yet strong and rigid when in use; hence the importance of the objects sought by my improvements.

Referring to the drawings which form a part of this application, and in which I have illustrated my invention- Figure l is a perspective View of the preferred form of my improved trestle. Fig. 2 is an end view of the same looking from the left-hand side of Fig. 1. Fig. 3 is a view in elevation, showing the trestle folded; and Fig. 4 is a detail showing a modified form of the horizontal top bar which forms a part of the trestle As indicated in the drawings, a a2 represent the two outside legs, and Z9 b2 the two inside legs, which serve as the supports for the horizontal top bar d. The legs a' a2 are of the same length and somewhat longer than the legs b' b2, as shown in Fig. 3. The legs o. b' are pivoted together, and the legs c2192 are pivoted together, as shown at n; as, said pivotal points being approximately midway of the lengths of said legs. The upper ends of the legs a d2 are connected by a bolt c', which passes through the elongated slot d', formed in thebard and extending therethrough for a little more than one-half of its length. The bolt c is only of sufficient length to permit the ends of the legs ct a2 to slide along the sides of the bar d when the trestle is folded or extended.`

The upper ends of the legs b b2 are connected by a bolt c2,which passes through a bolthole in the end of the bar d, which is posi tioned between the ends of the legs b b2. The bolt c2 is somewhat longer than the thickness of the legs and bar, thus permitting the former to spread apart to admit therebetween the legs a a2 when the trestle is folded, as shown in Fig. 3. The legs H192 move freely on the bolt c2, so that when the lower part of said legs is spread their upper ends may come together or bear on the adjacent end of the top bar d.

In order to secure the necessary rigidity, I secure a strap f to the outer edges of the legs b b2, near their upper ends, thus positively limiting the spread of the legs at this point and acting as a counterbrace for the spreader e, which is pivoted to the edge of the leg a and when in use has its hooked end engaging a screw or pin in the corresponding edge of the leg b2. This spreader not only serves to space apart the legs b b2, to which it is directly attached, but also to spread the legs a a2, thus causing the upper ends of the latter to bind against the sides of lthe top bar, which they embrace, with sufficient force to lock the legs at any point alonglthe slotted portion of the top bar. This feature or function of my invention permits the adjustment of the trestle as to height, as it is manifest that the nearer the upper ends of the legs a a2 are brought to the upper ends of the legs b' b2 the higher the top bar d will be raised above the floor.

When the trestle is not in use, the spreader e is disengaged from the leg b2, the legs a' a2 are folded together between the legs `b b2, which brings do'wnbetween theformer legs the bar d, whereupon all the legs and said bar are in the same plane, as shown in Fig. 3. It will be noted that the engagement between the upper-ends of the legs a' a2 and the top IOO bar d is positive, though sliding, so that there is no possibility of the bar being knocked up` when in use, thus upsetting the paste-board, paper, the.

In the modification shown in Fig. f1 instead of slotting the top bar I cut a shallow groove in its under edge, as cl2, and over the outer end of this groove I secure by screwing to the under side of the bar a metal plate g, which serves to catch and hold the bolt c when the trestle-legs are expanded or unfolded. While this form makes a stronger construction for the top bar, it is not adjustable, as with the preferred form, (shown in Figs. l to 3,) for the reason that the top baris not positivelylocked to the legs a a2 until the bolt c is engaged by the metal plate g.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, isy l. A trestle composed of four legs pivoted together in pairs, one pair adapted tofold between the other pair, the oppositely-placed legs of each pair connected at their upper ends by bolts, the bolt connecting the outer pair being longer than the thickness of said legs whereby they may freely move longitudinally on said bolt when the legs are folded and unfolded, a rigid strap connecting the outer pair of legs above their pivotal point, a top bar pivoted on the bolt connecting the upper ends of the outer legs and'slidably mounted on the bolt connecting the upper ends of the inner legs, and a spreader for the outer u HARRY E. HOVARD.

Witnesses:

R. G. ROBERTS, F. BENJAMIN.

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