US67347A - Ctjxt - Google Patents

Description

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JACOB REEF, JR., OF OLNEY, ILLINOIS, ASSIGNOR TO WILLIAM H. WILLIAMSON, FRANK POWERS, AND IIIRAM W. WHITE, OF SAME PLACE'.

Letters .Patent N 67,347,A dated July 30, 1867.

IMPROVED TRESTLE AND SGAPFOLD SUPPOBTBR.

TO ALL WIIOM IT JAY CONCERN: y k y Y Be it known that I, JACOB REEF, Jr., of Olney, in the county of Richland, and State of Illinois, have invented a new and improved Adjustable Trestle; and I do hereby declaro the following to be a full, clear, and exact description of the saine, reference beinghad to the accompanying drawings, which are made a part of this specification.

Figure 1 is a perspective view Vrepresenting my improved trestle as set up for use, and partially extended in height and length.

Figure 2 is a perspective view showing it folded as for transportation.

vSimilar-letters'of reference indicate corresponding parts in both views.

My trestlefframe consists essentially of two membera, each constituting an inverted right-angled triangle,4 and adapted to slide one past the other for extension and contraction in length. The-legs are also made extensible for adjustment in height, yand connected to the upper part of the frame by bolts, so as to fold longitudinally thereon. The triangular form gives to each member of the frame, within itself, great vertical strength, but trestles of this description heretofore made have been found defective in the vertical strength of the connection between the two members.

My most important improvement corists in the combination with the two triangular frames of an extensible bar attached to the vertex or lower part of each inverted triangle, forming a tie to prevent the spreading of the legs, and thus a'ord secure vertical support to the centre or junction of the two members of the frame.

In the drawings, A A represent the top bars; B B-the posts or legs; C C transverse beams connectingI and bracing each pair of legs; D D the bottom bar connecting the cross-beams C C at their centres, and E E diagonal braces connecting the cross-beams C C with the top bars AA'. AThe top bars A are adapted to slide one upon the other, as also the two lower tie bars D D', and the two parts B B of each leg, and these corresponding parts are coupled together by metallic bands a a, secured upon the extremity of one part'and clasping around and sliding upon the other. Pinspp are provided to tixthe frame at the required degree of extension.A The crossed braces EE are adapted to freely pass each other vertically and longitudinally when the trestle is undergoing adjustment, and at their upper extremities are attached to the under side of the bands surrounding the top bar by hinges admitting of vertical motion, in order that said braces E E may be folded up against the under side ot' the top bars A A for transportation. At their lower extremity the diagonal braces E E are stepped in notches cut in the outer upper edge of the cross-beams C C', having shoulders bearing against the inner edge of the crossbeams to give them greater firmness under heavy pressure from above. They are further fastened to the cross-beams by the pins lt. The extremities ofthe top bar A A are firmly ixed. between the upper extremities of the legs B B', one part of the bar A being fixed between the ends of one pair of legs, and the other part, A', being att: cbed in like manner to the other pair of legs. 0f the legs, composed, as before described, of'two parts sliding on each other, the inner part is the one attached to the top bar by bolts G, andthe outer piece slides 'up and down upon the inner, forming the extension piece, and resting on the ground when the apparatus is extended. The cross-beams C C are made of the proper length to give the frame the requisite stability. It will be observed that the parts A E B and A E B form' tn'o independent triangular frames, each possessing great intrinsic strength, and adapted to be adjusted in relation to each other without having their sustaining'capaeity impaired, as hereinafter explained.

The operation of this instrument is exceedingly simple: Withdraw the pnspp in the top and bottom bars and pull the triangular frames cf the trestle apart 'to the required extent, then' insert the pins again, passing each pin through the two corresponding parts. Then remove the pinspp in the legs B B'l and elevate the trimgular frames together vith the tie hars D D to any required height, and again insert the pins, passing them through both pieces t`1at compose the leg as before, and the instrument is ready for use in the new condition. The braces E E' Imppcrt the extremities of the respective top bars A A', and when the trestle is extended longitudinally the adjustable tie bars D D', connecting the lower parts of the two-triangular frames, rprevent their spreading, and thus entirely obviate the weakening of the device by its extension.

Among other advantages of this improved instrument are the following: First, its original cheapness of 1,., o construction. `In one hour any ordinary mechanic can saw out the various pieces for two of these trestles, it them, bore holes, &c.antl any blacksmith can put them together witlr'good strong iron bands, wrought-iron hinges, and bolts at small cost. Second. its simplicity. There is no multiplicity of screws, taps, and wrenches; no slots and combination of two pieces of timber in one; no braces to be adjusted; no uprights distinct from the legs, nothingbut timber, bands, holes. 'and pins. Repairs therefore will be simple, and can cost but a triile. Third. strength. As the-timber is solid andaiot out ont in the centre, or at the ends where the legs are jointed, while the parts of the legs mutually brace 4each other, and as the weight on the pins presses perpendicularly and without leverage, a glance will shoivits'superior advantages in this respect. l

but which afford firm interni support to the legs. The pins t,-confining the bottom ofthe braces E E', are made to pass through the ends of the bottom extension har D D', one set of pins thus answering as fastenings for both braces and the bars. Being folded in this manner the apparatus can be readily taken through doors and windows, and can be carried with other articles, such as lumber, sash, Sie. Fifth, perfection of Increment.

histrestle can be extended further. in proportion toits size, than any other device of the kind in use. When elevated it gains its own height minus the widthef the two bands of metal. Thus a six-foot trestle, on elcvation, will stand eleven feet si): inches at least. When elevated the width of its base is proportionately increased, so that it stands with equal firmness at every elevation.'v When adjusting the trestle for different elevations the crossed braces adjust themselves. They are always in place and need no attention. By attaching the two bands a a of each extensible leg B D', one to the upper end of the lower member B', and enclosing and sliding on the upper member, lthe other tothe lower end of theupper member B, and enclosing and sliding on the lower member, they ferm their own stops in extending the legs to their extreme length, guide the sliding leg with littlefriction throughout its motion, and support it against lateral strain.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is- 1. The extensible tie har D D', when used in combination with the sliding bars A A', legs B B', and diagonal braces E E', as and for the purposes setvforth. i

5.. The legs B connected to the bars A. A by bolts G, affording rigid lateral support, and adapted to told longitudinally against the hars as represented. Y l

3. In combination with the sliding legs B B' of a. trestlc of the construction described, I further claim the two barils a a, one attached to the upper end of the slidingr leg B' and enclosing the leg B, the other attache-1 to the lower end ofthe leg Il and enclosing the leg B', as and for the purposes set forth.

JACB REEF, JR. Witnesses:

J. WILEY, J. F.' WILSON.

Fourth, portability. BJ yremoving the bottom bar and throwing up the braces E E from their notches thc legs B B fold longitudinally f against the sides of the topliar, being attached to 'said top bur by bolts through the side, upon'which they hinge,

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