US2926746A - Ladder assemblies - Google Patents

Description

March 1, 1960 Filed June 5. 1957 Y. ST-MARS LADDER ASSEMBLIES 2 Sheets-Sheet l Eon J'fjllais' March 1, 1960 Y. ST-MARS 2,926,746

LADDER ASSEMBLIES Filed June 5, 1957 2 Sheets-Sheet 2 1 71/60 for 1 Filo/z J'fflfary United States Patent LADDER ASSEMBLIES Yvon St-Mars, Verdun, Quebec,- Canada, assignor to Trinity Ladder. Inc., Verdun, Quebec,.Canada Application June 5, 1957', Serial No. 663,639

3 "Claims. 01. 182-26)" Thi'sinvention relates to ladderstand hasspecial reference to a plurality of ladder: assemblies and means for arranging one or more of such assemblies: for various uses such as for a single ladder; step ladder; an inverted Y -shaped ladder, a slidable or extensible ladder; a trestle or scafiold support and the like;

One important object of this invention is to provide a novel pair of like ladder assemblies having; interlocking hinge means at their upper'ends. for readily connecting said" assemblies ininverted V -shapedt manner, the; hinge means being easily disconnected so that the ladder assemblies may be used individually.

A second important object of the. invention is; to provide such apair of assemblieswith a: third similar assembly adapted to bezmounted slid'ably selectively on one of. the pair of assemblies toconstitute a slidable extension of the selected assembly.

With the above and other objects in view,. as will be presently apparent, the invention consists in general of certainnovel details of construction and combinations of partshereinafter fully described,.i1lustrated in theaccompanying drawings, and particularly claimed.

In the drawings like: characters ofreference indicate like parts in 'the several VlEWSgCfil'ldZ Figure 1 is a side elevation showing all; threeof the ladder assemblies used in this invention;

Figure 2 is a sectional view parallel to Figure 1 and showing the principal elements of thatfigure;

Figure 3 isan enlarged detail elevation of the upper part ofFigure 1 but showing an extension assembly'raised andtsupporting a trestle board;

Figure M4 is an elevation of'the"device;, the viewbeing taken from the left side of Figure 1;:

Figure 5 is a perspective view of the lower end of a side rail of the extension device used herein;

Figure 6 is a section on the line 6 6 of Figure 1; V

'Figure7 is a sectionon the-line 7-7' of Figure 1;

Figure 8 is a detail enlarged side elevation of the lower ends of the ladder assemblies of Figure 1 in closed position;

Figure 9 is a greatly enlarged detail of the upper part to show the hinge construction of this invention in the open position of the ladder assemblies;

Figure 10 is a view similar to Figure 9 but showing the hinge with the ladder assemblies closed;

Figure 11 is a plan view of Figure 10;

Figure 12 is a detail view in elevation showing the extension assembly raised;

Figure 13 is a detail sectional elevation of parts shown in Figure 12;

Figure 14 is a section on the line 14-14 of Figure 13;

Figure 15 is a detail elevation of the upper part of the invention showing a modification of a ladder assembly;

Figure 16 is a section on the line 16-16 of Figure 15; and

Figure 17 is a sectional detail on the line 1717 of Figure 10.

In the invention, a preferable form of which is here 1 shown, there is provided a: pair of like ladder assemblies I and 2. The assembly 1 is formed of a spaced pair of channels 3 (Figure 6) forming the side rails of this as:- sembly and arranged in confronting relation with. the fianges of thechannels directed inwardly of the assembly. The channels 3 are held in spaced relation by spaced tubular rungsS" having ends anchored. in the angles formedby the web of each channel and one of its flanges. The-assembly 2 is of similar forinhaving spaced confronting channels 4 (Figure 7) held in spaced relation by rungs 6.- The lower ends of these ladder assemblies are curved apart as at- 7 and 8 and their side rails have cushioning shoes 9 and" 10 fitted on their lower ends. These channels are preferably formed of light. extruded metal.

hr order to: provide means for readily connecting and: disconnecting the upper ends of assemblies 1 and 2 and; for holding the'assemblies in hinged relation when desired, plates-11 of rectangular form, each having one end mounted on the outer face of a respective side rail 4 and there secured. by rivets 12, by welding or in any other suitable manner. Each of the plates 11 is. of suificient length toextend' over the upper end of a side rail 3 of the other assembly. Each of the plates 11 is bent inter-- mediate its ends to provide a U-shaped guide 13 open towards side rail? 3*. Projecting from each side rail 3 is a pin 14 (Figure 17) which is adapted to engage in the guide 13. Pins 14 may be mounted in the ends of tubular rungs 5- and also may be provided with down turned heads 15". Guide clips 16 are riveted to plates 11 and in these clips lti-arelfitted a pair of slidable rods 17, eaoh havin'g one end forked as. at 18 to extend through holes 18a formed? in the sides of the bend 13. The outer ends of the' rods 17 arebent' downwardly at 19 to provide fi'ngergrips-for effecting movement of the forked ends 18 into and out of position to straddle the pins 14 thus, hingedly connecting the upper ends of assemblies 1 and 2 and enablingsthem tobe readily disconnected.

Ii1-addition of assemblies 1 and 2, the device of the present invention: includes a third ladder assembly 20 having side rails 21 formedfrom extruded. flanges but in this assembly the channels face outwardly so that the side rails" 21 may interlock slidably with the side rails 3 of 'assemblyl'in the: manner shown in Figures 6 and 11. Theside rai1s-21' are held in spaced relation by rungs 22 having their ends welded on or riveted to the webs of the side rails adjacent one flange of the latter. At

" their lower ends: the side rails 21 are provided with notches 23* formed: in:- the channel webs, the flanges of these channels being cut. back as. at 24 to allow for the engagement with-:channel3as seen in Figure 3.,

When it is desired to use the invention as a step ladder the assemblies 1 and 2 are spread as in Figures 1 and 2 and are held in this position by means of a knuckle jointed stretcher member 25 having its ends pivoted to the middle portions of these assemblies. On the lower rung 22 of ladder assembly 20 is rockingly mounted a pair of downwardly facing hooks 27 which by engagement with a selected rung of assembly 1 will hold assembly 20 in safe position when raised as in Figures 12 and 13.

Assembly 20 may be partially raised as in Figures 12 and 13 or fully raised and inclined relative to assembly 1 as in Figure 3 for supporting a trestle board 26. Blocks 28 are formed in the channels of the side rails 21 and serve to properly space assembly 20 from assembly 1.

When it is desired to hold the assemblies 1 and 2 to form the extension ladder made of the three assemblies as shown in Figures 12 and 13, clips 30 fixed to side rails 3 are inserted through notches 31 formed in a flange of a side rail 4 and positioned as in Figure 1-4. A clip 29 is pivoted at 50 to each of the plates 11 and engages the side of the side rails 3. The object of clip 29 is to hold together the assemblies 1 and 2 when sliding assembly 1 relatively to assembly 2 for passing from the step ladde'r formation to the extension ladder formation shown in Figures 12 and 13, the forked ends 18 ofrod 17 being out of engagement with the'pins 14. l

To form a top for the device a hinge plate 32 is fixed to the top of assembly 2 and a platform 33 carried by the other plate 32a of the hinge has a spring clip 36 fixed beneath its free edge to engage to top rung 22 of assembly 20. Also a step 34 (Figure 15) may be rockingly mounted at 56 on a rung 6 and supported by chains 35 if desired.

It will be plain that the assemblies may be used as an inverted V-shaped 1 and 2 structure with the assembly 20 mounted on assembly 1 in telescopic engagement therewith, assemblies 1 and 2 may be disconnected and used individually, may be arranged to form a broad base supporting the extension assembly 20 and in various other manners for different purposes. Also, as shown in Figures 12 and 13, the three assemblies 1, 2 and 20 may be arranged to form a straight extensible ladder.

It will be noted that the fact that the rungs and 22 are respectively disposed adjacent one flange of the channels 3 and 21, permit a maximum spacing of the rungs 5 and 22 for forming a wide step while enabling to make an extension ladder of minimum overall thickness as clearly shown in Figure 5. Moreover, the lateral displacement of the rungs results in sufficient clearance between assemblies 20 and 1 when arranging the three assemblies as shown in Figure 3.

The manner of pivotally interconnecting the ladder assemblies 1 and 2 by bolt 17 and pins 14 enables to easily transform the arrangement of the present invention from the step ladder formation shown in Figure 1 to the straight ladder formation shown in Figures 12 and 13. In the latter case, the additional means provided by clip 30 prevent relative pivotal movement between ladder assemblies 1 and 2.

Although specific embodiments of the invention have been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention as indicated by the appended claims.

What I claim is:

1. An extensible ladder comprising first, second and third ladder assemblies, each assembly formed of channel shaped side rails and transverse rungs interconnecting said rails, pins laterally projecting from the side rails of said first assembly at both ends thereof, locking means at the upper end of said second assembly for removably engaging said pins to pivotally connect either end of said first assembly to said second assembly and allow relative pivotal movement of said first and second assemblies about the engaged pins, latching clips on one assembly removably and slidably engageable with the other assembly of said first and second assemblies to slidably and removably retain said first and second assemblies in side by side relation and prevent relative pivotal movement of said same assemblies, whereby said first and second assemblies can be pivotally connected together by said locking means and by the pins at the upper end of said first assembly in the manner of a step ladder or can be rigidly secured together as an extended straight ladder by said latching clips and by said locking means engaging the pins at the lower end of said first assembly, said third assembly being in telescopic engagement with said first assembly and booking means on said third assembly engageable with said first assembly to permit adjustable extension of said first and third assemblies relative to each other.

2. An extensible ladder as claimed in claim 1, wherein further pins project laterally from the side rails of said first assembly at spaced intervals along substantially the entire length of said side rails, said locking means capable of removably engaging any of said pins to thereby permit adjustable extension of said first and second assemblies relative to each other when connected in the manner of an extensible straight ladder.

3. An extensible ladder as claimed in claim 2, wherein the rungs are tubular, narrower than said rails and fixed to said rails adjacent a flange thereof and spaced from the other flange thereof the channels of said first assembly being oppositely disposed with respect to the channels of the third assembly so that the flanges of the channels of said first assembly face inwardly of the as sembly and the flanges of the channels of said third assembly face outwardly of the assembly, said first and third assemblies being in telescopic engagement with the outward flange of said third assembly remote from the rungs of said third assembly abutting against the rungs of said first assembly, said hooking means maintaining the rungs of the first and third assemblies in associated pairs, so constructed and arranged that the rungs of each pair have a maximum distance apart while the overall thickness of the two engaged first and third assemblies is a minimum.

References Cited in the file of this patent UNITED STATES PATENTS 151,150 Murray May 19, 1874 2,131,802 Harmon Oct. 4, 1938 2,143,783 Liebman Jan. 10, 1939 2,470,053 Salisbury July 8, 1946 2,636,659 Salisbury Apr. 15, 1949 FOREIGN PATENTS 140,391 Australia Mar. 5, 1951

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