US1323227A

US1323227A - Convertible jtepladder

Info

Publication number: US1323227A
Authority: US
Publication date: 1919-11-25
Anticipated expiration: 1936-11-25

Description

A. S. KIRBYM CONVERTIBLE STEPLADDER. APPLICATION FILEDJUNEZM 191B.

3 SHEETS-SHEET 2.

a1 J29 A/44] I 2,2 6 40 ZJ A. S. KIRBYQ .CONVEBTIBLE STEPLADDER.

APPLICATION FILED JUNE 24. I918.

Patented N 0v. 25, 1919.

a SHEETSSHEET 3.

nivrrnn srnrns PATENT or-rron.

ABNER S. KIRBY, OF FREDERIOKTOWN, OHIO.

CONVERTIBLE STEPIi ADDER.

To all whom it may concern:

Be it known that I, ABNER S. KIRBY, a citizen of the United States, residing at F redericktown, in the county of Knox and State of Ohio, have invented certain new and useful Improvements in Convertible Stepladders, of which the following is a specification. 7

This invention relates to an improved step ladder and has as its primary obj ect'to provide adevice of this character which may be adjusted to form a wall ladder.

The invention has as a still further object to provide a device of the above described character employing swingingly connected ladder sections normally disposed to provide a step ladder which may be mounted from either side and wherein the said sections will be adjustable with respect to each other for varying the height ofthe step ladder.

A still further obj ectof the invention is to )rovide an arrangement wherein the step ladder will be rigidly supported by suitable side braces against lateral tilting and wherein the said braces may be adjusted to compensate for any adjustment in the height of the step ladder. 7

And a still further object of the invention is to provide an arrangement wherein the ladder will be equipped with adjustable foot bars so that the ladder may readily rest upon uneven ground.

Other and incidental objects will appear as the description proceeds, and in the drawings wherein I have illustrated the preferred embodiment of the invention, and wherein similar reference characters desig nate corresponding parts throughout the several views:

Figure 1 is a side elevation of my improved step ladder,

Fig. 2 is an end elevation of the device,

Fig. 3 is a transverse sectional view taken on the line 38 of Fig. 1 and particularly illustrating the adjustable connection between the side braces of the ladderand the connecting bars between the ladder sections,

Fig. 4 is a transverse sectional view taken on the line 4-4: of Fig. 1 and looking in the direction of the arrows, this view particu- Specification of Letters Patent.

Application filed June 24, 1918. Serial No. 241,577.

larly'showing the construction and mount ing of the upper platform of the ladder,

Fig. 5 is a sectional view taken on theline 55 of Fig. 1', and showing the type of guide loop employed at the upper ends of the foot bars for the ladder,

Fig. 6 is a transverse sectional View taken on the line 6 6 of Fig. 1, and showing the type of guide 100p employed at the lower ends of the bars, and

Fig. 7 is a fragmentary edge elevation showing the manner in which the sections o-f the ladder are adjusted to provide a wall ladder.

In carrying out the invention I employ coacting ladder sections 10 andll'respectively. The section 10 includes substantially parallel side rails 12joined by suitable spaced steps or rounds 13. In like manner, the section 11 includes substantially parallel side rails let joined by suitable spaced steps or rounds 15. Asparticularly brought out in' Fig. 2, the upper ends of the rails 14 of the section 11 are adapted to fit between the uptially midway of the ends thereof are. transverse connecting bars 18. These bars are, as

particularly shown in Fig. 3, provided at their inner ends with suitable bosses lying against the outer sides ofthe railsl of the ladder section 11 and extending through these bosses as well as through the said rails is a rod 19 swingingly connecting'the connecting bars with the said "ladder section. At its outer end the rod 19 is preferably equipped with a wing nut 20. The bars 18 adjacent'their outer extremities are formed with longitudinally extending slots 21 and loosely fitting through these slots trans- *icularly brought out in 3 of the di wings the connecting bars are tapered lo a 'itudmally from their outer ends toward 1' inner ends. Consequently, after the g nut 23 has been once set, any tendency 0 1e ladder sections to spread at their tree ext "emit-ies will cause these connecting bars to wedge between the side rails 12 of the section 10, the head of the rod 22 and the w ng nut and thus effectually overcome such movement. it the same time this wedging action of the connecting bars will tend to prevent accidental displacement oi the said wing nut.

Arranged at the outer side of the ladder are vertical braces 2 These braces throughout the major portion of their length are provided with longitudinally extending slots 25 through which the bolt 16 is fitted for connecting the braces at their upper ends with the apex of the ladder. Interposed between the upper ends of the said braces and the side rails 12 or" the ladder section 10, are suitable washers 25 upon the said bolt and, as will, of course, be readily understood, the nut 1? of the rod 16 may be readily adjusted for clamping the braces fixed against vertical movement with respect to the rod. Securing the intermediate portions of the braces to the connecting bars 18 are bolts 26, which are loosely fitted through the slots 21 of the said bars and, at their outer extremities, are freely received through the slots 25 of the braces. These bolts are preferably equipped with wing nuts 27 and interposed between the connecting bars and the braces are suitable washers 28 supporting the braces with respect to the said bars in such position that, as particularly shown in Fig. 2, the bars diverge laterally with respect to the ladder from their upper extremities toward their lower extremities. The wing nuts 27 of the bolts 26 may, of course, be easily adjusted for clamping the braces in vertical position. In this connection it is to be particularly noted, as also best shown in Fig. 2, that the braces are tapered from their lower extremities toward their upper extremities. Consequently, any tendency of the braces to move upwardly, under the wei ht oi a load upon the ladder, will cause the said braces to wedge at their upper extremities between the washers 25, the head of the bolt 16 and nut 17, and, at the bars 18 between the wing nuts 27 and washers 28. Such wedging action will, of course, bind the said braces to effectually resist such vertical movement, while, at the same time, the nut 17 and the wing nuts 27 will be locked against accidental displacement. The braces will thus be rigidly held to support the ladder against lateral tilting in either direction.

Adjustable upon the lower extremities of the side rails of the sections are a plurailty of foot bars 29. These bars are, as particularly shown in Fig. 1, provided with longitudinally extending slots 30 and fitted through the rails of the ladder sections to loosely engage through said slots, are pairs of spaced bolts 31 preferably equipped with wing nuts 32 operable for clamping the foot tions. The

guide loops

33 and 3% are thus adapted to slidably support the foot bars upon the rails of the ladder sections for movement to project below the lower ends thereof and, as will be readily understood, the several foot bars may, when it is desired to rest the. ladder upon uneven ground, be readily adjusted for supporting the ladder in an erect position. The foot bars are, as particularly brought out in Fig. 2, also tapered longitudinally from their lower ends,

toward their upper ends so that any tendency of the said rods to shift upwardly upon the rails of the ladder sections, under the weight of a load upon the ladder, will act to wedge the said bars between the said rails and the wing nuts 32 of the bolts 31 and con sequently bind the said bars in fixed position. At the same time, such wedging action will also tend to lock the nuts against accidental displacement. As will e seen, these foot bars and guide loops therefore, while being particularly designed for use in connection with the present invention, are nevertheless adapted for general a-ppli cation and may accordingly be applied to and efiectively employed upon various types of ladders already in service.

Mounted upon the uppermost of the rounds 13 and 15 of the ladder sections is a platform 35. This platform includes spaced upper and lower members 36 supported in parallel r lation a suitable spacing block 37 interposed between said members, as particularly shown in F5 g. 4-, at a point substantially midway between the ends thereof. Connecting the said members and extending through the block are bolts 38, The

uppermost of the rounds l3 and '15 of the ladder sections are slidably received between the extremities of the members 36 at opposite sides. of the block 37. Consequently, while the said platform may be shifted upon the said rounds transversely wit-h respect to the ladder, the block 37 will, nevertheless, hold the said platform against displacement. This provides an arrangement whereby should the platform be found in the way when mounting the ladder at one side thereof, the said platform may simply be shifted to the opposite side. Mounted upon the outer extremities of the connecting bars 18 is a second platform 39. This platform is detachably connected with the bars by loops 4O loosely receiving the terminal portion of the said bars and is held against displacement by pins 41 removably fitting in suitable openings in the upper edge of the bars. Preferably, the pins 11 are connected with the platform, as best shown in Figs. 1 and 2, by suitable flexible elements to prevent accidental loss of the said pins. Since the platform 39 is somewhat lower than the platform 35, it will be seen that I have provided an arrangement whereby a workman may stand upon the lower platform while a bucket or other utensil of the workman may be rested upon the upper platform in convenient position.

As will now be seen in view of the preceding description, by releasing the wing nut 20 of the rod 19, the wing nut 23 of the rod 22, the wing nuts 27 of the bolts 26, and the wing nut 17 of the bolt 16, the

ladder sections

10 and 11 may be spread at their lower extremities for adjusting the height of the ladder, when the said nuts may again be tightened up for clamping the several parts in adj ustedposition. In this way the height of the ladder may be easily varied. When the ladder is thus adjusted, the platform 39 is, of course, first removed by displacing the pins 41 and should the ladder sections be spread to such extent that the members 36 of the platform 35 will not reach between the uppermost of the rounds of the ladder sections. this latter platform may also be removed.

In order to form the device into a wall ladder, the connecting bars 18 and braces 24: are removed as are also the platforms 85 and 39. The bolt 16 is then removed when the

ladder sections

10 and 11 are disposed in alinement, as shown in Fig. 7 with the inner ends of the side rails 14 of the section 11 abutting the uppermost round 13 of the section 10. In this position of the said sections the bolt openings adjacent the upper ends of the side rails of the section 10 will register with similar bolt openings 42 formed in the side rails of the section 11 adjacent the uppermost round 15 of the said tions against inward movement relative to,

each other. The foot bars at thelower end of the section 10 may, of course, be readily adjusted to support the wall ladder upon uneven ground and by employing the pairs of bolts 31 for holding the said bars in adjusted position liability of possible slipping of the said bars will be effectually overcome.

It will, therefore, be seen that I have provided a particularly efficient type of ladder and a ladder which may not only be used as an ordinary step ladder but may also be easily adjusted to form a wall ladder. Furthermore, when used as a step ladder the device will be rigidly supported against lateral tilting movement and may by proper adjustment of the foot bars thereof also always be arranged in an upright position without regard to any unevenness in the surface upon which the ladder is rested.

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

1. A. device of the character described including coacting ladder sections, means swingingly connecting said sections, a cross connection between the sections, and lateral brace means for the sections arranged at opposite sides thereof and held by said connecting means, said brace means being adjustable vertically upon said connecting means. 7

2. A'device of the character described including swingingly connected ladder sections, adjustable cross connecting means between the sections, and lateral brace means connected with the upper end portions of the sections at opposite sides thereof and engaging with the adjustable cross connecting means between the sections.

3. A device of thecharacter described including coacting swingingly connected ladder sections, connecting bars between the sections swingingly connected to one of the sections, and means adjustably connecting the free end portions of said bars with the other of the sections, the bars being longitudinally tapered to coact with said last mentioned section for holding the bars wedged against longitudinal movement with respect thereto. 7

4. A device of the character described including coacting ladder sections connected at their upper ends, cross connecting means be tween the sections, lateral brace means connected with the upper ends of the sections at opposite sides thereof, and means clamping the lateral brace means and cross connecting means together.

5. A device of the character described including coacting swingingly connected ladder sections, adjustable cross connecting means between the sections, lateral brace means arranged at opposite sides of the sections, and means adjustably connecting said lateral brace means With said cross connecting means.

6. A de ice of the character described including coacting ladder sections, cross connecting means between the sections, and lateral brace means arranged at opposite sides of the sections and clamped intermediate of their ends against lateral movement with respect to the sections.

In testimony whereof I am); my signature.

ABNER S. KIRBY. [1,. s.]