US1428370A - Ladder - Google Patents

Description

c. n. HARMON,

LADDER.

APPLICATION FILED SEPT.9, I920.

' Patented Sept. 5, 1922.

2 SHEETS-SHEET 1.

c. o. HARMON.

LADDER.

APPLICATION FILED SEPT. 9, 1920.

Patented Sept. 5,1922.

z'sucus-mmn 2 Khan/a3 fl Ear/Wan Patented Sept. 5, i922.

eairan stares CHARLES n. iaanivion, or JACKSONVlLLE, ILLIIVNOIS.

LADDER;

Application filed. September 9, 1920; Serial No. 409,211.

To all whom it may COW-067% Be it known that I, GHAnLns D. HA MON, a citizen of the United States, residing at Jacksonville, in the county of Morgan and State of Illinois have invented certain new and useful Improvements in Ladders, of which the following is a specification.

This invention relates to ladders of the type disclosed in Letters Patent No. 1,1 882, granted to M. M. Wood Aug. 3, 1915 the object of the present improvements be ing to simplify and improve the construction and thereby reduce the cost oi production without any loss of efliciency. The nvention is illustrated in the accompanying drawings and will be hereinafter fully described, the novel features being subsequently pointed out in the appended claim.

In the drawings Figure 1 is a perspective view of a ladder embodying my present improvements and arranged as astep ladder;

Fig. 2 is a plan view of a portion of the ladder shown in Fig. 1;

, Fig. 3 is a detail section through the connection between the sections 01'? the ladder;

Fig. 1 is a front elevation of a portion 0]": the ladder showing the same arranged as a wall ladder;

Fig. 5 is a longitudinal section ot the device arranged as shown in Fig. 4;

Fig. 6 is a detail perspective view of a portion of the ladder; v I

Fig. 7 is a view similar to Fig. 3, but showing a slightly different embodiment or the invention;

Fig. 8 is a detail perspective viewof the supporting brace which cooperates with the devices shown in Fig. 6.

In the drawings, the reference numeral 1 indicates a ladder section consisting oi? side bars and steps secured to and between the same, while the reference numeral? ind cates a coacting ladder section consist-mg oi side bars and rungs extending between and secured therein.

In carrying out the present invention, 1 secure to the ends of the side bars 3 oi the ladder section 2 a bracket 4 which may be a casting or may be stamped from sheet metal and comprises a side plate 5, a top plate 6 and end plates 7 so arranged as to fit around and over the end of the side bar, as clearly shown in Figs. 1 and 6. One end plate 7 is extended beyond the top plate 6 to present a tongue or lug 8 which serves as a stop as will be presently more specifically set forth On the inner side ofthebar 3 and spaced from. the endthereof is alateral lug or block 9 which is adapted to seat in arecess 1n the top step 10 ofthe ladder section land upon the sideplate ,5 is a headed stud 11 which is adapted to ride in a slot provided therefor upon the ladder section 1. The headof this stud is, elongated or llipti cal and is disposed obliquely relative to the top plate Got the bracket so that when in its operative position the ladder sections will be i I plate 14 and immediately adjacent the edge of the base plate 13, a stop lug or. finger 15 projects laterally, thesaid stop being recessed, as shown at 16, upon its inner edge to,

receive the tongue 8, as clearly shown in Fig. 1. At the junction of the base :plate 13, and the head plate 14 a notch 17 is formed therethrough and this/notch 17 registers with a similar notch 18 in. the edge of the top step 10 of the ladder. A longitudinal slot 19 is formed in the base plate 13' and terminates near the ends thereof, the upper terminal of the slot being extended laterally, as shown at '20, and having a tooth 21 formed on the lower wall of the said lateral extension whereby a notch 22 is produced in which the shank of the headed stud 11may seat. Preferably the slot 19 is defined by a head 28 struck up from the base plate 13 and adapted to overhang the projecting portions From the side edgeof the head i of the head of the stud 11 so that it will be unnecessary to cut a groove or slot in the side bar 12 of the ladder section and thereby weaken the same. The bracket may be a casting or may be stamped up'from sheet metal and in Fig. 3 I have illustrated the back wall of the base plate to correspond with the slot 23 while in Fig. 7 I have shown the back wall 24-. bridging the slot through which the shank of the headed. stud 11 passes.

In assembling the ladder sections, the section 2 is brought into such position relative to the section 1 that the heads of the studs 11 will have their long edges parallel with the sides of the slots 19, in which position the heads will readily pass through the slots. The ladder section 2 is then turned about the studs as centers so that the projecting ends of the stud heads will engage under the beads 23 or the edges of the slots 19. The ladder sections are then moved relatively longitudinally so that the studs 11 will pass to the upper ends of the slots 19, after which the ladder section 2 isInoved laterally to permit the shanks of the studs to seat in the notches 22 whereupon if the sections be swung so that their lower ends are separated, the tongues 8 will be caused to seat in the recesses 16, as clearly shown in Fig. 1, and spreading or" the ladder sections will be thereby prevented so that the apparatus may be safely used as a step ladder. When it is desired to use the device as a wall ladder, the section 2 is lifted slightly to release the studs 11 from the notches 22 and is then swung toward the section 1 to bring the studs into the slots 19, after which the two sections are shifted relatively longitudinally so that the tongue 8 will clear the stop finger 15, this operation being the reverse of that described for assembling the sections. The section 2 then is swung so that its lower end will move outwardly and upwardly about the headed studs as centers until the said section is brought into a position above and alined with the section 1, as shown in Fig. 4;, after which the section is permitted to move downwardly until the lug or rest 9 passes into engagement with the notches 17 and 18 in which position the ladder section 2 will be firmly supported by and above the section 1. Obviously, the ladder thus arranged will be placed against a wall so that the finger 15 will be at the front of the device, or with the ladder between it and the wall, and said finger will, consequently, effectually coact with the side bar of the ladder section 2 and the headed stud 11 engaged in the slot 19 to prevent collapse of the structure by the movement of the upper section from the wall. It will be readily seen from the foregoing description, taken in connection with the accompanying drawings, that I have simplified the construction and reduced the number of parts needed thereby lessening the cost of production without any loss of efficiency.

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

In a portable ladder, the combination of a main ladder section, a base plate pro- 'vided with a slot running in longitudinal direction of said section and secured to the upper end thereof, a head plate integral with and extending from the upper end of said base plate and secured over the upper end of said ladder section, there being registering recesses in the upper end of said ladder section and in the head and base plates, a second ladder section, a trough shaped bracket rigidly secured to and embracing the end and three sides of: said second ladder section, a stud secured in said bracket and provided with an elongated head adapted normally to have sliding engagement under said base plate with the shank of the stud running in said slot, interengaging means on the ends of the ladder sections for preventing separation of the same in the normal operating position and comprising a toe on said bracket and a hook on said head plate,

and a lug on said second section adapted to seat in said registering recesses in the extended position of the ladder sections, the narrow width of said stud head being slightly less than the width of said slot, whereby said head is adapted to slip through said slot when the ladder sections are in assembling position. 7

In testimony whereof I allix my signature.

CHARLES D. HARMON. [us]

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