US2749009A

US2749009A - Folding ladder

Info

Publication number: US2749009A
Application number: US443230A
Authority: US
Inventors: Lewis T Price
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-07-14
Filing date: 1954-07-14
Publication date: 1956-06-05
Anticipated expiration: 1973-06-05

Description

June 5, 1956 L. T. PRICE 2,749,099

FOLDING LADDER Filed July 14, 1954 2 Sheets-Sheet 1 Fig.2 I Fig.3

Lewis 7. Price IN V EN TOR.

BY MM 8% L. T. PRICE FOLDING LADDER June5, 1956 2 Sheets-Sheet 2 Filed July 14, 1954 Fig. 9

Lewis 7? Price INVENTOR.

United States Patent 9 FOLDING LADDER Lewis. T. Price, Tulsa, Okla.

Application July 14, 1954, Serial No. 443,230

6 Claims (Cl. 228.19,2)

Thisinvention relates -to a folding ladder, and more specifically provides -a ladder having stiles or side rails constructed of a plurality of sections that may be folded from an extended longitudinally aligned position to a folded parallel overlying position.

Anobject of this invention is to provide a folding ladder that is simple in construction, easy to fold into a compact condition for storage or transport and easy to unfold toan extended position, positively locked in its extended position, thereby preventing accidental folding, well adapted for its intended purposes and relatively inexpensive to manufacture.

Another object of this invention is to provide a folding ladder having side rails or stiles constructed of a plurality of hinged sections that form a lazy tong structure together with improved and novel locking means for rotaining the sections of the stiles in longitudinal alignment and permitting easy folding of the sections to a parallel overlying position.

A still further object of this invention is to provide a folding ladder wherein the side rails are constructed of a pair of longitudinally movable members wherein each of the members are constructed of sections hingedly interconnected together with means for preventing longitudinal movement of the side rail members except when the side rail members are disposed alongside each other with the sections thereof in longitudinalalignment.

Still another important object of the present invention is to providea folding ladder constructed of a lazy tong structure wherein bayonet slot interconnecting means is provided forreleasably locking the ladder in extended position.

These, together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure l is a side elevational view showing the folding ladder of the present invention in extended position and in operative position against a wall of 'a building or the like;

Figure 2is a front elevationalview of the construction of'Figure 1 showing the relationship 'of the hinge connection between the adjacent sections when the ladder is in extended :position;

Figure 3 is a ,sideelevational view showing the folding ladder-of the present invention in partially folded condition, showing the relationship of the side rail sections as the ladderis being folded or unfolded;

Figure 4 is a side elevational view showing the folding ladder ofthe present invention in its folded position wherein the ladder is compact for easy transport or storage;

Figure 5;is an enlarged side elevational viewshowing the details of construction, of adjacent sections ,of ,a portion of the side rails of 'the folding ladder;

2,749,009 Patented June 5, 1956 Figure 6 is a longitudinal, vertical sectional viewtaken substantially along section line 6-6 of Figure 5 showing the details of construction and the relationship of the. elements of the ladder side rails;

Figure 7 is a detailed sectional view taken substantially along section line 77 of Figure 6;

Figure 8 is a detailed and enlarged side elevational view showing one of the side rails when in its collapsed position, showing the relationship of the hinge connection between the adjacent section and theposition of the hinge pin. and locking projection;

Figure 9 is a longitudinal, vertical sectional view taken substantially along section line 9--9 of Figure 8 showing further structural details of the ladder side rail; when in its .folded position; and

Figure 10 is a detailed side elevational view showing the relationship of the pivot pin wherein the sections of the folding ladder are partially folded.

Referring .now specifically to the drawings, it will be seen that the numeral 10 generally designates the folding ladder of the present invention wherein the ladder 10 includesside rails having inner stiles or members 12 and outer stiles or side members 14. The inner stiles 12 are spaced laterally fro-m each other by a plurality of ladder rungs 16 which are preferably of cylindrical crosssection and connected to the inner stiles 12 in any con ventional manner. The inner-stiles 12 are constructed of a plurality of sections 18 and the outer stiles 14 are constructed of a pluralityof sections 20 with the sections '18 connected by hingemembers 22 and the sections 20 connected by hinge means 24 wherein the hinge means 22-and' 24- are disposed on alternate sides of the stiles 12 and 14 wherein adjacenttsections 18 ofthe inner stiles 12 vand adjacent sections 20 of the outer stiles 14 may. be folded to a parallelv and overlying position. The central portion of .the sections 18 is provided With a projecting pin 26. that is provided with a headed por- 7 tion 28, and the central portion of the sections 20 .are each provided with a slot 30 having a cylindrical portion 32 at its upper end,'and the pin 26 is generally polygonal in'cross-sectional areawith arcuate side edges 34 which are substantially similar to the circular portion 32'of the slot 30.

As seen in Figures 1-3, a pivotally mounted foot 38 is pivotally mounted tow the lowermost section 20 of. the

right angularslot having a horizontal portion 42 and a vertical depending portion 44. Adjacent the other end of each of the sections 20 is provided a horizontal slot 46 and at one end of each of the inner sections 18"is provided a projection 48 for a purpose described hereinafter.

Adjacent the lower end of the lowermost section 20 is providedsa projecting stud 50 and the lower end of the lowermost. section 18 is provided with a U-shaped notch 52 for a purpose described hereinafter.

In operation and with the device folded substantially as illustrated in Figure 4, it will be seen that the projection 48 on each of the sections 18 is received in the slots 46 wherein

theadjacent sections

18 and 20 of the inner and outer stiles 12 and 14 are positioned in parallel overlyingand engaging position. As the uppermost ends of the

uppermost sections

18 and 26 are grasped and raised, the sections 18 and 2il-pivot about pivot pin 26 until adjacent sections 18 of the inner stile 12 and adjacent sections 20 of the outer stile 14 are longitudinally aligned and coextensive. When this position is reached, the notch 52 is positioned directly over the stud 50 and the projection 48 on each section 18 is positioned in the horizontal portion 42 of the bayonet slot and the pivot pin 26 is disposed with the flat sides parallel to the vertical portion of the slot 30 wherein the inner stile 12 and the sections 18 will be moved longitudinally downwardly in relation to the outer stile 14 and the sections 20. This moves the projection 48 into the vertical portion 44 of the bayonet slot and moves the polygonal pin 26 downwardly into the vertical portion of the slot 30 and engages the notch 52 with the projecting stud 50, thereby securely locking the stiles 12 and 14in extended position wherein the

sections

18 and 20 are longitudinally aligned with the stiles 12 and 14 positioned alongside each other. As the stiles 12 move downwardly, the hinge connections 22 are misaligned with the hinge means 24 on the stiles 14 which also lock the ladder in extended position. When it is desired to fold the ladder 10, it will only be necessary to raise the inner stiles 12 in relation to the outer stiles 14 and pivot the

aligned hinge connections

22 and 24 in opposite directions wherein the hinge pins 26 which have been raised out of the vertical portions of the slot 30 into the cylindrical portion 32 will pivot the sections 18 and about each other, thereby removing the pins 48 from the horizontal portions of the bayonet slot, and moving the notch 52 away from the stud 50. As the

sections

18 and 20 are folded to the position substantially as illustrated in Figure 4, the projections 48 will engage the respective notches 46 in the end of the sections 20 remote from the bayonet slot wherein the

adjacent sections

18 and 20 of the inner and outer stiles will overlie and engage each other wherein the device will be folded in a compact condition. Obviously, the various elements of the invention may be constructed of readily obtainable materials by well known manufacturing processes, thereby enhancing the economic feasibility of the invention.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What is claimed as new is as follows:

1. A folding ladder comprising a pair of stiles interconnected by a plurality of longitudinally spaced rungs, each of said stiles formed of a plurality of terminally hingedly connected sections, a side member positioned alongside each of said stiles, each of said side members formed of a plurality of terminally hingedly connected sections of substantially the same length as the stile sections, the central portions of the side member sections and the adjacent stiie sections being pivotally secured together thereby forming a lazy tong structure, and means for locking the lazy tong structure in extended position, said sections being provided with a centrally positioned pivotal and slidable connection wherein the stiles and side members are longitudinally movable in relation to each other, and said locking means including a projection on one section, and a bayonet slot on the other sections wherein the projection will be engaged with the entrance of the slot when the sections are moved alongside each other and locked in the slot when the sections are moved longitudinaly of each other, said projection and slot being spaced from the pivotal and slidable connection between adjacent side-by-side sections thereby locking said sections in side-by-side relation wherein the side members and stile are locked in extended position.

2. A folding ladder comprising a pair of stiles interconnected by a plurality of longitudinally spaced rungs, each of said stiles formed of a plurality of terminally hingedly connected sections, a side member positioned alongside each of said stiles, each of said side members formed of a plurality of terminally hingedly connected sections of substantially the same length as the stile sections, the central portions of the side member sections and the adjacent stile sections being pivotally secured together thereby forming a lazy tong structure, and means for locking the lazy tong structure in extended position, said sections being provided with a centrally positioned pivotal and slidable connection wherein the stiles and side members are longitudinally movable in relation to each other, and said locking means including a projection on one section, and a bayonet slot on the other section wherein the projection will be engaged with the entrance of the slot when the sections are moved alongside each other and locked in the slot when the sections are moved longitudinally of each other, said projection and slot being spaced from the pivotal and slidable connection between adjacent side-by-side sections thereby locking said sections in side-by-side relation wherein the side members and stile are locked in extended position, said sections being foldable for overlying each other, a slot on the other section receiving said projection when the sections are folded to a parallel overlying position.

3. A folding ladder comprising a pair of stiles interconnected by a plurality of longitudinally spaced rungs, each of said stiles formed of a plurality of terminally hingedly connected sections, a side member positioned alongside each of said stiles, each of said side members formed of a plurality of terminally hingedly connected sections of substantially the same length as the stile sections, the central portions of the side member sections and the adjacent stile sections being pivotally secured together thereby forming a lazy tong structure, and means for locking the lazy tong structure in extended position, said sections being provided with a centrally positioned pivotal and slidable connection wherein the stiles and side members are longitudinally movable in relation to each other, and said locking means including a projection on one section, and a bayonet slot on the other section wherein the projection will be engaged with the entrance of the slot when the sections are moved alongside each other and locked in the slot when the sections are moved longitudinally of each other, said projection and slot being spaced from the pivotal and slidable connection between adjacent side-by-side sections thereby locking said sections in side-by-side rela tion wherein the side members and stile are locked in extended position, each of said side members being provided with a stud projecting inwardly from the lower end of the lower section thereof the lower end of the lower section of each of the stiles having a longitudinally extending notch for receiving the studs whereby the sections will be retained in parallel position when the stiles move downwardly in relation to the side members after the side members and stiles are extended to a parallel position.

4. A folding ladder comprising a pair of stiles interconnected by a plurality of longitudinally spaced rungs, each of said stiles formed of a plurality of terminally hingedly connected sections, a side member positioned alongside each of said stiles, each of said side members formed of a plurality of terminally hingedly connected sections of substantially the same length as the stile lections, the central portions of the side member sections and the adjacent stile sections being pivotally secured together thereby forming a lazy tong structure, and means for locking the lazy tong structure in extended position, said side members being longer than the stiles and provided with a bayonet slot and a central pivot slot for permitting longitudinal movement of the stiles from an unlocked upper position, with the hinge connections A pair of outer stiles, ladder rungs interconnecting the inner stiles, each of said inner and outer stiles constructed of a plurality of hingedly connected sections forming lazy tong stiles for folding to a parallel overlying position and extending to a longitudinally coextensive position with the inner and outer stiles positioned alongside each other, and means pivotally connecting the central portion of the sections of each of the inner stiles to the central portion of the sections of the adjacent outer stiles.

6. A folding ladder comprising a pair of inner and a pair of outer stiles, ladder rungs interconnecting the inner stiles, each of said inner and outer stiles constructed of a plurality of hingedly connected sections forming lazy tong stiles for folding to a parallel overlying position and extending to a longitudinally coextensive position with the inner and outer stiles positioned alongside each other, and means pivotally connecting the central portion of the sections of each of the inner stiles to the central portion of the sections of the adjacent outer stiles, and releasable interlocking means on the stile sections for locking the sections in longitudinal alignment and permitting folding of the sections to a parallel overlying position.

References Cited in the file of this patent UNITED STATES PATENTS 294,879 Johnson Mar 11, 1884