US341535A - Step-ladder - Google Patents

Description

(No Model.)

s. WRIGHT.

STEP LADDER. No. 341,535.v Patented May 11, 1886.

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UNITED STATES PATENT OFFICE.

SAMUEL WEIGHT, on rEoEIA, ILLINoIs.

STEP-LADDER.

SPECIFICATION forming part of Letters Patent No. 341,535, dated May l, 1886.

Application filed September?, 1885. Serial No. 176,366. (No model.)

To all whom it may concern:

Be it known that I, SAMUEL WRIGHT, of Peoria, in the county of Peoria, in the State of Illinois, have invented an Improved Step-Lad der, and I do hereby declare that the following is a full, clear, and exact description there of, reference being had to the annexed drawings, making a part of this specification, in which like letters of reference refer to like parts, and in which- Figure l represents a perspective view of the ladder; Fig. 2, a detail sido view of the upper portion of the ladder; Fig. 3, a View of the ball part of the ball-andsocket joint that unites each prop-stick to the upper step or platform of the'ladder; Fig. 4, a plan view of the socket of said joint; Fig. 5, a plan view of the bracket for joining the stile to the platform-step; Fig. G, a side view of the same with section of said socket; Fig. 7, asectional view of the joint which unites the vertex of the triangular brace to theplatform-step; Fig. 8,asec tional view showing the fastening for joining the lower corners of the triangular brace to the prop-sticks; Fig. 9, a view of the cross-bar of the triangular brace to which the holding-link of the prop-sticks connects; Fig. l0, a view of the extensible stile-slide; Fig. ll, a sectional edge view of same; Fig. 1 2, a side view of the forked brace for the stile-steps; Fig. 13, a front view ot' the same.

This invention is of that class of step-ladders in which the prop-sticks are adapted to have a more or less independent swing, whereby to enable the same to stand firmly upon uneven ground.

What this invention particularly relates to is the effecting of improvements in the various details of construction-wiz., the brace for supporting the prop sticks against lateral pressure, the joints for securing said brace to the prop-sticks and the stile, the joints for pivoting the prop-stcks to the stile, the braces for strengthening the steps, and the means for enabling the stile to have either or both sides elongated.

To permit the prop-sticks of a step-ladder to have independent swing, for enabling them to rest evenly upon rough ground, and still so bracing them as to have them hold the ladder Ir'nily against any side pressure, is the object of the part of my invention which consists of the triangular framewhich is loosely secured to the prop-sticks and the stile. From a suit'- able cross-bar in this triangular frame a link extends to one of the steps of the stile, and the joints of said frame to the prop-sticks and to the stile being sufiiciently loose, the propsticks and the frame can be oscillated more or less about a vertical axis, so as to bring the lower ends of said prop-sticks at unequal distances from the lstile, one, prop-stick approaching the stile in thesame proportion that the other receded therefrom.

In the drawings, A A represent the side bars of the stile; A, the upper step or platform thereof, and A2 the intermediate steps.

B B are the prop-sticks, secured at their upper ends to the platform A by means of the ballandesocket joints E.

Y Cis the triangular frame consisting of the bars C C and Ct'.

At the junction of the two bars C is the joint, which, to permit the movement of the triangular brace C required by the unequal placing of the prop-sticks, I construct as follows: Between the joined ends of said bars C', I usually fasten the triangular block Ji, vertically through which and said bar ends,exteriol thereto, is bored the hole J i. 'ithin this hole J'l is inserted the easily-movable pin J, the npper end of which is provided with the eye J. By means of this eye and the socket-piece J said pin is pivoted to the under side of the platform An This joint permits, it will be noticed, the required loosenoss of connection of the triangular brace C to the plat-form, and yet is sufficiently rigid against lateral displacement to fit the brace for its office.

The pivotal center of the pin J must be approximately in line between the universal joints connecting the prop-sticks to the platform, so that the amount of vertical play' of the pin J in the brace, or rather the play of the brace C on said pin, shall not be increased above that required, for the hereinafter-stated reasons.

When the prop-sticks B are at equal distances from the stile, both they andthe triangular b race C are in the same plane. Vhcn, however, said sticks are relatively displaced, they are in non-parallel planes, and the triangular brace C is in still another plane. rI'his, there fore, necessitates a pivotal connection of the IOO lower corners of the brace C to the prop-sticks B, which is accomplished by means of the bolts B passing through suitable apertures in said prop-sticks and held to said corners by the straps K', through which they pass. These straps K being firmly nailed or otherwise fastened about said corners, and the said bolts K having the heads Kz at their ends within said straps, the desired rotation of joints is permitted, and yet the brace C is securely heldvto the prop-sticks. Fig. 8 shows said joints K.

To keep the prop-sticks B from spreading too far away from the stile when upon smooth surfaces is the purpose of the link H, which is at one end attached to a step of the ladder, and at the other end to the cross-bar G. This cross-bar is secured to the triangular brace C by being formed of malleable iron made with the lugs G and lips G2. Said lugs G being in serted into indentations in the wood, and the lips G2 being bent thereabout, as in Fig. 9, the crossbar G is securely held in place without screws or rivets.

The brackets for securing the stiles A to the platform A consist of the horizontal strips D', adapted to be fastened to the under side of said platform', and of the semicircles D adapted to be fastened to the said stiles.

The means for hinging the prop-stieks B to the platform A consist of the sockets E, secured to said platform, and of the balls F, inserted within said sockets and rigidly affixed to the said prop-sticks. The balls F, I usually form of cast metal, and fashion therewith the clips F2, separated therefrom by the short neck F. Said clips inclose between them the upper part of the prop-stick, and rivets or screws being inserted through said clips and the propstick, the ball F is thereby rigidly secured to the end of said prop-stick. To lighten each ball F, I do not form it as a complete sphere, but have it consist of three zones meeting each otherat rightangles. Each socket Eis formed with ears E, whereby to screw the same to the under side of the platform A. The notch or slot E', through a portion of said socket, is for the passage of the neck F of the ball F. To secure the ball-and-socket joint firmly to the bracket D, there is formed the dovetail notch E2 in said socket E, and the bracket D is provided with the projection D2, made dovetailed at its base to fit said notch. The, extremity of said projection D`Z is bent downward to partially close the slot E and form an abutment thereat for the ball F. The center portion of the projection D2 becomes an abutment to receive the direct upward pressure of the ball F. This union of the bracket and the socket enables me to dispense with other fastenings for said bracket than the screw at D5.

For the sake of lightness the stiles A are usually split and separated a short distance.

'Io brace these split stiles and the steps-firmly together I have devised the forked brace R, the single end of which is screwed to the under side of the step, and the bifurcated ends to the two parts of the split stile. By this forked brace R not only is the step securely braced against each of the two parts of the stile, but.

said split stile is thereby held more firmly together.

To perfectly adapt the ladder to rest firmly vupon the most uneven surfaces, I make each -and adapted to have its lower end engage with said corrugated strip M by means of the spring P2,embedded within a recess in the stile, and held in position in its contact with the dog by the lug P, thereby enables the slide L to be held at any desired point of elongation. By impressing the upper ends of the said dogs P their lower ends are thrown out of engagement with the slides, and the latter can then be returned up in place. By means of the crescent springs O,which I sometimes insert between the slides and their stiles, said slides are thereby aided in staying in place against the pull of gravity. I usually, however, form the springs I2 of the dogs P sufficiently powerful to keep said slides up in place without any extra help.

In using my step-ladder all that is ordinarily necessary to do is simply swing the propsticks out away from the ladder, when the lower ends thereof, coming in contact with the ground, so turn the prop-sticks that one touching nearer the ladder and the other farther away rest firmly and evenly. In case the ladder itself does not stand sufciently upright, one or other of the extension-slides L is pushed downward until the required evening up thereof is procured.

Although I have shown the triangular brace C as having its vertex secured to the platform A, this triangular brace can be inverted, the bars C being pivoted either to the platform A or to the upper Vportions of the prop-sticks, and the vertex thereof attached to the cross-bar C2 by the joint-J, said cross-bar not being displaced fromv its former position, the essential part of the triangular brace C being that of its ability to turn in different planes than the prop-sticks and yet be rigid against any lat# eral deflection.

What I claim as my invention, and for which I desire Letters Patent, is as follows, to wit:

1. The combination, with the step-ladder having the prop-sticks loosely hinged to it, of

the brace consisting of the three bars secured together to form the rigid triangle, and loosely attached at its vertices to the prop-sticks and IOO IIO

ladder, substantially as and for the purpose specified.

2. The combination, with the step-ladder having its prop-sticks loosely hinged thereto,

of the triangular brace C, attached at its lower corners to the prop-sticks and at its vertex to the platform of the ladder, and having the cross-bar and link` connecting the same to a step of the ladder, substantially as and for the purposes set forth.

8. In a joint for permitting the triangular brace C to have a reciprocal, oscillatory, and rotative movement, the combination, with the said brace C, having the hole J 2, of the pin J, removablein said hole and having the eye J', and a socket-piece for said eye, substantially as and for the purpose specified.

4. The combination, with the step-ladder, its prop-sticks, and the triangular brace C, of the triangular block J having the hole J 2 therein, the pin J, removable in said hole and having `the eye J', and the sockct-picce J3 for said eye, for the purpose set forth.

5. The combination, with the step-ladder, its prop-sticks, and the triangular brace, of the block J t, having` the hole J2, the strap J5, the pin J, having eye J, and the socketpiece J, for pivoting said pin to the upper step of the ladder, substantially as and for the purpose specified.

6. In ajoint for attaching the lower corner of the triangular brace G to the prop-stick B, the bolt K, passing through the prop-stick and having nut K2, and the strap K, affixed about the corner of said brace, all combined as and for the purpose set forth.

7. In a balland-socket joint, the socket E, having notch E, in combination with the ball F, formed of three zones meeting at right angles, and having the clips F2 proj cctin g from its neck F', as set forth.

S. The combination, with the step-ladder and its prop-sticks, of the bracket D, attached to the said ladder and having the dovetailed projection D2, and the socket E, having dovetail notch Ff, and the ears E.

E, adapted to fit said dovetail, and also having the deep notch E and the ears E, and the.

ball F, adapted to fit within said socket, and having the clips F2 projecting from its neck F', substantially as and for the purpose set forth.

10. In a cross-bar, the bar G, formed of malleable metal and having the lugs G and the lips G2, as and for the purpose specified.

1l. The combination, 'with a ladder having split side bars, of the forked brace It, having its bifurcated ends It secured to the said split side bars, and having its single end attached to the step, substantially as set forth.

12. In a step-ladder of the kind having slides at thelower ends of the stiles longitudinally adjustable by means of serrations in the slides and dogs engaging therewith, the combination, with the step-ladder, of the slides having longitudinal grooves therein, and serrated metallic strips inserted in said grooves,

and the dogs engaging with said serrations, as and forthe purpose set forth.

13. In a stcpdadder ofthe kind having slides at the lower ends of. the stilcs longitudinally adjustable by means of scrrations in the slides and dogs engaging therewith, the combination, with thc step-ladder, of the slides having longitudinal grooves therein and the serrated metallic strips in said grooves, the dogs engaging with said serrations, and having the lugs and the coiled springs kept in place by means of said lugs and recesses in the ladder, as and for the purpose specified.

14. rIhe combination, with the step-ladder SAMUEL VRIGHT.

In presence of A. B. UPHAM, p H. W. WELLs.

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