US2781158A

US2781158A - Ladders

Info

Publication number: US2781158A
Application number: US393176A
Authority: US
Inventors: Nathan S Raitt
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-11-19
Filing date: 1953-11-19
Publication date: 1957-02-12
Anticipated expiration: 1974-02-12

Description

LADDERS Filed Nov. 19, 1953 nkuma";

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United States Patent LADDERS Nathan s. Raitt, Norfolk, Va.

Application November 19, 1953, Serial No. 393,176

' 2 Claims. (Cl. 228'51) This invention relates to ladders primarily intended for extending overridges of roofs to be held thereby; the requirements of roof and chimney inspection, painting and the increasing use of roof antennae create a demand for means that can be readily placed in position and safely used by home owners and artisans other than experienced roofers. It is to meet this demand that is an objective of this invention.

For securing roof ladders in position a common expedient is the provision of hooks or equivalents to engage the roof ridge. Since such hooks or the like project downward from the end of the ladder, it becomes necessary either to hold the ladder above the roof at the lower end or to slide the projections over the shingles with likely damage or loosening of the shingles. Even the lightest ladders of metal, however, are not easily manipulated from the lower end when standing on another upright ladder resting against the roof eaves. Moreover, it is generally desirable to be able to descend some distance on the far side of the roof, as around a chimney, and projections or hooks offer little or no provision for that purpose. In addition it is frequently necessary to shift a ladder along the roof, and projections interfere with or prevent easy lateral movement.

According to the present invention the foregoing disadvantages are overcome. In brief, their accomplishment rests in providing a roof ladder having pivoted at or near one end a second ladder section that functions both as a ridge-engaging means and as a ladder for descending the other side of a roof, the movement of the pivoted section being remotely controlled from the far or lower end of the main section of the ladder. By the remote control it becomes possible to secure the pivoted section in alignment with the main section and thus free from interfering projections in order to slide or shift the ladder over the roof, and to rotate the pivoted section, when it projects over the ridge, into contact with the far side of the roof from the lower or far end of the main section; and all of this can be accomplished while standing on another upright ladder leaning against the eaves.

In the accompanying drawing an embodiment of the invention is illustrated, in which Fig. l is a side elevation of a two-section ladder, shown as resting on a roof indicated by dotted lines;

Fig. 2 is a fragmentary enlarged rear elevation of Fig. l in the direction 2-4;

Fig. 3 is a fragmentary top view in the direction 3-3;

Fig. 4 is a fragmentary top view in the direction 4-4;

Fig. 5 is a fragmentary side view opposite to that of Fig. 1;

Fig. 6 shows a modification in side elevation corresponding to that of Fig. 1;

Fig. 7 is another modification showing a tread in place of a rung and a rounded foot or end of the ladder; and

Fig. 8 illustrates two different cross-sections of the ladder side pieces.

'Ihe ladder comprises a main section 11 and an auxiliary 2 section 12, the main section having

side pieces

13, 14 connected by rungs 15 and the auxiliary section having

side pieces

16, 17 connected by rungs 18. The side pieces are preferably channel beams of aluminum or other light metal (shown in section in Fig. 8) with the channel 19 turned to the outside, and the rungs (or treads as shown in Fig. 7) are preferably of the same metal. A rung 20, second from the top of the main section, projects through the

side pieces

13 and 14 and through registering openings 21 in

side pieces

16 and 17 of the auxiliary section to form pivot joints (Fig. 5); a block 22 rein-- forces the channels 19 of the side pieces. 7

For rotating the auxiliary section on the pivot rung 20 into alignment with the main section 11, a pulley 30 (Fig. 5) is mounted within the channel 19 of the projecting end 31 of the side piece 14. A stop 32 engages the side piece 14 when the ladder section 12 is rotated into alignment.

Attached to the stop is a line (cord, cable or wire) 34 passing through slot 35 in the channel and over the pulley- 39 and through another slot 36 to the upper side of the side piece 14; from here the line extends to the foot 37 of the main section, where it can be secured to a cleat. It is to noted that the attachment of the line to the stop, carried by the section 12, is in contraposition to the projecting end 33 of the section relative to the pivot rung 20.

When the line 34 is released, the section 12 rotates out of alignment by its own weight. It can, however, be rotated and also locked in any angular position, as shown in Fig. l where it rests on the roof, by means of another line 40. This is attached to the other projecting end 41 of the auxiliary section side piece 16 and passes over a pulley 42 mounted on the projecting end 31 of the main section side piece 13. The line runs along the side piece to the foot 37 of the main section for attachment to a cleat 43. In the modification of Fig. 6, the pulley 42' is shown mounted within the channel and slots 44, 45 permit ingress and egress of the line 40.

When the section 12 is rotated into alignment, the stop 32 engages the main section side piece as before stated. This stop is supplemented by additional stops 50, 51, which slip past the beveled ends 52 of the main section side pieces to engage the flanges 53; these additional stops can be omitted or can replace the stop 32.

The operation of the ladder appears to need little explanation. The auxiliary section is first locked into alignment with the main section, and in this position there are no projections on the underside to catch into shingles or to interfere with hoisting the ladder and sliding it up over the roof. When the ladder is positioned with the pivot rung 20 at the ridge, the line 34 is released to permit the auxiliary section to rotate down into engagement with the roof on the other side of the ridge. It can be assisted in this movement by pulling on the line 40, and when the section rests on the roof, the line 40 can be secured to lock the section in place; this insures against slipping of the main section when it is subjected to a downward pull by the weight of a person on it. To remove the ladder the auxiliary section is pulled back into alignment by the line 34.

The ladder can be of wood; but, because of the weight of the wood, light metals or metal alloys are preferred, since the ladder needs to be lifted and slid over the roof white the operator is perched on another vertical ladder resting against the eaves.

Obviously the invention is subject to other embodiments. The side pieces of the auxiliary section can be pivoted inside of the side pieces of the main section; in this modification, the top rung of the main section is shifted to the auxiliary section, the second rung being the pivot, and the projecting ends of the auxiliary section can hook or otherwise engage the third rung of the main Patented Feb. 12, 1957.

section. Other control means can be devised to take the place 'of the pulleys and lines; for instance, "a gear secured at the pivot point to aside piece of the auxiliary section and projecting into the channel 19 ,of the main section can be engaged by a worm on the end; of a'iong shaft "extending along the channel to ithe footof the main section for rotation therefb y: bevel igears or the like; .7 r 1 o What is claimed is: J h o 1. Ladder for'use on roofs comprisingin combination:

tive to the "projecting end, said lines having movable engagement with theprojecting end of the main section andexte'nding therealong to the remote end of the main section for engagement therewith to hold the auxiliary section in adjusted position.

2. Ladder for use on roofs comprising in combinaytion-z 'a "main section; an auxiliary "section; pivot means connecting the two sections and spaced from an end of each of the sections to provide projecting ends; and 7 means for adjusting the pivotal position of the auxiliary section relative to the main section, said means comprising a pair of lines, one of said lines secured to the projecting end of'the auxiliary section and the other line secured to the auxiliary section Ton the far side of the pivot means relative to the projecting end, and pulleys on the projecting end of the main section for receiving said lines and directing them to the remote end of the main section for'engagement therewith to hold the auxiliary section in adjusted position.

References Cited in the file of this patent VUNITED STATES PATENTS 7 V r 473,768 Mitchell V 'Apr. 26; 1892 724,423 Benigar Apr. '17, 1903 1,160,721 Kessler NOV. 16,1915

Marriner Sept. 15, 1942