US295269A - miller - Google Patents

Description

(No Model.)

n J. T. MILLER. TRESTLB FOR SGAFFOLDING.

No. 295,269. PatentedMar. 18, 1884.

(No Model.) 2 sheetssheet 2.

J. T. MILLER.

TRESTLE IEORv SGAFFOLDING.

No. 295,269. Patented Mam. 18, 1884.

'WTNESSES Unirse STATES I PATENT @einen JOHN rr. MILLER, on MnMPHIs, MIssoUnI.

TRESTLE FOR SCAFFOLDING.

SPECIFICATION forming part of Letters Patent No. 295,269, dated March 18, 1884.

Application filed August 8, 1883.

To all whom, it may concern:

Be it known that I, JOHN T. MILLER, a citizen of the United States, residing at Memphis, in the county of Scotland and State of Missouri, have invented certain new and useful Improvements in Trestles for Scaffolding; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making a part of this specification, and to the letters and gures of reference marked thereon.

Figure 1 of the drawings is a perspective view of my invention ready for use. Fig. 2 is a similar View of the same in its folded position. i

The present invention has relation to certain newand usefulimprovements in that class of trestles for sca-ttolding adapted to be folded in a compact form when not'in use; and the object thereof is to provide a trestle that will Abe strong, durable, and simple in its construction, and, in addition to the advantage of folding together when not in use, may be ex- 2 5 tended toany desired height, and iirmly and securely held in such extended position Without danger to the workman, it being capable of sustaining a great anionntof weight, and owing to its lightness and simplicity of construction this trestle is easily handled, and may be readily carried about from place to pla-ce, to suit the convenience of its owner, and is also capable of being manufactured at a greatly-reduced cost. These several objects above stated I attain by the construction substantiall y as shown in the accompanying drawings, and means hereinafter more fully described.

In the drawings, AB represent two sections of the trestle, provided with cross-braces a and horizontal braces b, the latter being secured to the sections .near their upper and lower ends, at the termini of the cross-braces. These sections A B have suitably secured to their standards c, near the inner upper ends, wire cords d, which cross each other and are fastened to the lower inner ends of the standards of their opposite sections, said wire cords being drawn taut when the sections are expanded, thus 5@ forming very strong though extremely light braces, to prevent lateral motion of the said No model.)

sections when expanded, the sections, when in their expanded position, being kept securely apart by jointed spreaders e, pivotally secured to the standards c at or near their upper and lower ends.

To prevent the Wire-cord braces from sagging outwardly when the trestle is folded up, I employa spiral spring or elastic cord,f, the ends of which are loosely secured around said 6o braces at their point of crossing, the contracting force of said spring or elastic cord acting to take up the slack and draw the wire cords inwardly when the sections are brought together in their folded position.

The standards c of the sections A B are each provided with a groove extending its entire length, said grooves acting as guides `for spring-bolts y, secured to the lower horizontal braces, and extending through the standards 7o ot' extensible sections C D, said sections being similar in construction to the ones A B, with the exception that their cross and horizontal braces are located `upon the inside instead of the outside. ySecured to the upper ends ot the standards of these sections C D are suitable angle-irons, h, which act as hinges and form bearings for a cross-piece, E, upon which to rest the boa-rd orboards forming the stage or platformof thescaffolding, said cross-pieceSo being preferably rounded, to prevent the trestles from rocking by the sagging of the staging or platform. rThe grooved standards c of the sections A B are provided with perforations arranged at suitable distances apart, said perforations extending through the ungrooved portion of these standards on a line with the direction of' and forming bearings for the spring-bolts g Vof the sections C D, thus admitting of these latter sections being raised or 9o lowered to suit the convenience of the workman.

Depending from the upper horizontal brace of one of the sections C D is a loop or spiral spring, t, having hung thereto a ring, lt, from which depend cords or wires connecting with a lever, F, pivotallysecured to the lower horizontal brace of said sections, said lever in turn being suitably connected to the ends of the spring-bolts y.

To Withdraw the bolts from any of the per forations in the grooved standards of the sec IOO tions A B with which they may be engaged, it is only necessary to draw up the ring k, and thereby, through the medium of the cords and levers, the bolts are drawn back and the sections C D raised or lowered, as may be ldesired. That portion of the bolts which enters the perforations in said standards when drawn back slides in the grooves, and thus prevents the sections from becoming disengaged during this operation.

Though I have described the cords or wires as engaging with the pivoted lever, in turn connected with the spring-bolts, this lever may be dispensed with, and the cords or wires ar ranged to engage directly with said bolts; or other suitable means may be employed for their withdrawal. y

The hinged sections O D, if desired, may be removed from the sections A Band used as a short trestle, it being a trestle in itself when thus detached.

Not only can the sections' C D be used for an independent trestle, but the ones A B may also be thus used, as they are kept firmly apart by their spreaders e, and a board or boards forming the stage or platform of the scaffolding may be either laid upon the tops of their standards or upon the upper horizontal braces.

Having now fully described my invention,y

. jointed spreaders pivotally secured at or near their upper and lower ends, said sections having their standards grooved and perforated to form guides and bearings for suitable bolts connected to the inner hinged sections, as and for the purpose specied.

3. The outer folding sections, constructed as herein described, and provided with wire cords adapted to cross each other in opposite directions, substantially as shown, to form braces when said sections are expanded and held apart by their spreaders, and a spiral spring or an elastic cord having its ends loosely secured around said wire cords at their point of crossing, as and for the purpose set forth.`

4. The two inner sections, constructed substantially as described, and provided at their upper ends with suitable angle-irons which form bearings for a supporting cross-piece, and in connection therewith hinges for the sections, said sections having connected to their lower horizontal braces'suitable bolts adapted to slidein grooves'a'nd'engage with the perforations'in the standards in the outer sections, and means for operating said bolts, substantially as and for thepurpose specified.

5. The two outer sections, constructed substantially as described, having grooved and perforated standards, and provided with wirecord braces'and jointed spreaders, in combination with a spiral spring or elastic cord loosely secured tosaid wire braces, and the hinged inner sections having a suitable crosspiece, andvprovided with' spring-bolts and means for operating the same, as and for the purpose set forth.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses.

JOHN r. MILLER.

Witnesses:

N. E. OLIPHANT, GEO. R. PORTER.

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