US2418862A

US2418862A - Convertible ladder

Info

Publication number: US2418862A
Application number: US577612A
Authority: US
Inventors: James S Anderson
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-02-13
Filing date: 1945-02-13
Publication date: 1947-04-15
Anticipated expiration: 1964-04-15

Description

1947- J. s. ANDERSON 2,418,862

CONVERTIBLE LADDER Filed Feb. 15, 1945 2 Sheets-Sheet l 1: naemon,

April 4 J. 5. ANDERSON 2,418,862 CONVERTIBLE LADDER Filed Feb. 13, 1945 2 Sheets-Sheet 2 Wow Patented Apr. 15, 1947 2,418,862 CONVERTIBLE LADDER James S. Anderson, Vancouver, British Columbia, Canada Application February 13, 1945, Serial No. 577,612

2 Claims. (Cl. 228-2) The present invention relates to new and useful improvements in ladders and more particularly to a convertible ladder adapted for use for diflerent purposes, such as a straight ladder, step ladder, as a scaffolding support and for various other purposes where a ladder isdesired.

An important object of the invention is to provide a, convertible ladder of this character in which the parts may be folded into compact form.

A still further object is to provide a convertible ladder of simple and practical construction, which is strong and durable, relatively inexpensive to manufacture, which may be easily and quickly arranged in its several forms for different purposes and which otherwise is well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, refert pole 9 extends between a a o conver in of one of the folding rungs and with parts broken away and shown in section.

Figure 16 is a top plan View thereof.

Figure 17 is a detail sectional view, taken on the line il-ll of Figure 15.

Referring now to the drawings in detail and first with respect to the form of the invention As illustrated more clearly in Figure 12 of the drawings, the upper ends of the side rails 6 are provided with metallic cover plates 8 to protect forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a front elevational view showing the device arranged as a straight ladder.

Figure 2 is a side elevational View thereof. Figure 3 is a side elevational View of the ladder arranged for use as a step ladder.

Figure 4 i a front elevational View showing the device as a scaffolding support.

Figure 4a is a side elevational view thereof.

Figure 5 is a fragmentary top plan view of one of the rungs of the ladder extension showing the bracket provided for accommodating the connecting bar between the upper and lower sections of the ladder.

' Figure 6 is a side elevational view thereof.

Figure 7 i a sectional view taken substantially on a line 'l-l of Figure 6.

Figure 8 is a side elevational view of a modi- 4O U shaped bracket fied scaffolding support.

Figure 9 is an enlarged side elevatio-nal view of the brace for the scaffolding support.

Figure 10 is an edge elevational view with parts broken away and shown in section.

Figure 11 is a transverse sectional view taken substantially on a line li-H of Figure 9.

Figure 12 is an enlarged detail in elevation of one of the folding rungs for use with a straight ladder.

Figure 13 is an enlarged edge elevational View of one or the braces shown in Figure 4a. (Figure 14 is a side elevational view thereof.

Figure 15 is an enlarged side elevational view the converging ends of the rails l l.

One of the rungs I2 is separated centrally of its length as indicated in Figures 5 to 7, inclusive, the separated meeting ends of the rungs being 45 side walls of the bracket, as indicated in dotted in Figure 7. This gives ample rigidity to the lad der and prevents folding of the adjoining sections on the hinge joint I 3. So, too, while sufiicient rigidity may be given to the ladder by merely tightening the pivots I0 and it, it is obvious that further dependable rigidity is aiiorded by the aforesaid provision of the interfitting and attaching arrangements of the bracket It to the adjacent end portion of the pole member 9 and adjacent the pivot Hi. It is further obvious that the same bracket provision and arrangement may be made to supplement the tightened pivot 10. Rigidity of the straight ladder arrangement is further augmented by the provisions and arrangements to be now described.

The outer edges of the plates 8 are rolled to form bearings 11 in which a bolt 58 is journaled, the bolt being removably secured transversely of a folding rung it of tubular construction and hollow at its outer end to form a chamber Ell with-, in which a pin 2! is slidably mounted and projected outwardly by means of a coil spring 22 positioned within the chamber inwardly of the pin (see Fig.

The outer end of the rung I9 is formed with a hook 23 adapted to receive a rope or cable 24 clamped in position within the hook by means of the outwardly projecting end of the pin 2!. The rung i9 is formed with a longitudinally extending slot 25 through which a button 25 carried by the pin 2! projects to provide for the manual retraction of the pin in order to release the rope or cable 24, when desired.

The ends of the rope or cable 2 are attached to projections 21 on the ends of the rungs l as well as to similar projections 28 on one of the rungs l2 and the pole 9 is provided at opposite sides with folding rungs 29 similar to the rungs I8 and likewise embodyingmeans {or gripping the ropes or cables 24 to provide an intermediate ladder section extending between the lower ladder section 5 and the upper ladder section H and thus provide a substantially straight rigid ladder. Obviously, instead of using originally flexible ropes or cables as the members it, the same may be rigid rods, bars or strips of metal or wood. If the latter are used it is not necessary to apply excess longitudinal tension to the members as is necessary with ropes or cables to give the required rigidity to the structure.

The cables or ropes 25 may be detached from the folding rungs I9 and the folding rungs moved into folded position or removed by removing the bolt l8 from the bearing l1 and the pole 9 and upper extension ll swung into a position to form a step ladder as shown in Figure 3 of the drawings.

For this purpose the lower and

upper sections

5 and 11 are secured in spaced apart relation by means of a foldable sectional brace indicated generally at 28 and illustrated in detail in Figures 9 to 11, inclusive.

The brace 29 comprises a pair of plates 38 and El pivotally connected to each other at one end by means of a pin 32, the plates being slidably mounted in channel-

shaped extensions

33 and 35, respectively. The outer ends of the extensions are formed with openings 35 adapted for pivotally attaching to one of the rails of the upper and lower ladder sections.

The plate 38 and extension 33 are formed with longitudinally extending slots 36 through which a bolt and wing nut iii are inserted for securing the extension 33 in longitudinally adjusted position on the plate 3% and the plate 3! and extension 34 are formed with similar longitudinally extending slots 38 through which a bolt and wing nut 39 are secured for likewise securin the extension St in longitudinally adjusted position.

The ladder may likewise be arranged to provide a support for one end of scaffolding as illustrated in Figure 8 of the drawings by positioning the pole 9 horizontally and supporting the lower end of the ladder extension H on a step 40 so that planks M for the scaifolding may be supported on the ceived in a longitudinally extending slot 50 horizontally arranged pole 9. In order to support the planks 4| two of the ladder units are provided, one at each end of the planks.

Inwardly disposed end of the pole 9 may be provided with a resilient pad 42 to prevent injury to the wall 43 of a building while the scaffolding is in use.

The ladder may also be converted into a modified form of scaffolding support as illustrated in Figures 4 and 4a of the drawings and for this purpose the ladder extensions l I are removed and the pole 5 supported in a horizontal position on the upper end of the lower ladder section 5 by means of one or more braces 44. This form of the brace comprises upper and

lower plates

45 and 46 having their ends arranged in overlapping relation, the plate 45 being secured to one of the rails H of the upper ladder section by means of a bolt 41 and the braces 44 are secured to the respective side rails of the upper ladder section H by means of a pair of clamping plates 48 extending horizontally thereof.

The lower end of the plate 45 is provided with a pair of bolts and wing nuts 49 adjustably reformed in the plate 46 for securing the plate 46 in longitudinally adjusted position with respect to the plate 45.

Th lower end of the plate 46 is formed with a notch 5| adapted for engaging one of the rungs l of the lower ladder section 5.

Having thus described the invention, what I claim is:

l. A convertible ladder comprising a pair of ladder sections, one of said sections being of lesser length than the other section, each section including side rails converging toward one end, a pole member pivotally connected to the narrow end of the longer one of said sections, said pole member being pivotally connected to the narrow end of the shorter section, means for rigidly fastening said pole member and. said shorter section in longitudinal alignment with each other and from relative pivotal movement in such alignment, a detachable brace for connecting said sections in an upstanding relative position with he sections flaring apart in a downward direction and with the pole member in the said longitudinal alignment with the shorter section and pivotally attached to the narrow end of the longer section, said ladder being reconvertible into a straight ladder by removing the detachable brace and swinging the rigidly connected shorter ladder section and the pole member at the pivotal connection between the pole member and the longer ladder section so that the longer and shorter ladder sections and the intermediate pole member are in longitudinal alignment with each other, the intermediate pole member and the adjacent end portions of the two ladder sections being provided with rung extensions at opposite sides thereof. and rail members secured intermeiate their ends to the rung extensions of the ladder sections and of said intermediate pole member, the opposite ends of said rail members being secured to the opposite sides of the ladder sections.

2. A convertible ladder comprising a pair of ladder sections, one of said sections being of lesser length than the other section, each section including side rails converging toward one end, a pole member pivotally connected to the narrow end of the longer one of said sections, said pole member being pivotally connected to the narrow end of th shorter section, means for 5 rigidly fastening said pole member and said shorter section in longitudinal alignment with each other and from relative pivotal movement in such alignment, a detachable brace for connecting said sections in an upstanding relative position with the sections flaring apart in a downward direction and with the pole member in the said longitudinal alignment with the shorter section and pivotally attached to the narrow end of the longer section, said detachable brace being foldable and longitudinally extensible, the ladder assembly being reconvertible into a straight ladder, the reconversion being efiected by removing the detachable brace and swinging the rigidly connected shorter ladder section and pole member on the pivotal connection of the pole member with the longer ladder section so that the two ladder sections and intermediate pole member are in longitudinal alignment with each other, said pole member and the adjacent end portions of the ladder sections being provided on opposite sides with foldable rung extensions, and detachable rail members attachable intermediate their ends to the outer ends of the foldable rung extensions on the end portions of the ladder sections and said intermediate pole member, the opposite ends of said rail members being attachable to th opposite sides of the ladder sections.

JAMES S. ANDERSON.