Патент USA US2408373код для вставки
Oct. 1, 1946. ’ - . J, DE F, CHASE‘ -' LADDER EXTENSION 2,408,372 ' Filed Nov. 10, 1944 g 60.4», onooo‘0T; .24 :23 désse ?eiéreéf 6774.96, 3%)”, @éw W5 2,408,372 Patented Oct. 1, 13946‘ UNITED ’ STATES‘ PATENT 2,408,312 _ ’ Lennon EXTENSION ~ Jesse, De ForestChase, Kansas CitygMo. ‘in. . _ * ' ‘Application November 10, 1944, Serial No. 562,8151 2 Claims. (01. 228-63) 1 recesses H, the plate being slidably mounted on the pins [3 and retained in position thereon by The present invention relates to new and useful improvements in attachment for ladders and more particularly to an extension adapted to be attached to the lower end of one of the side rails of the ladder to increase the length thereof whereby to permit the ladder to stand level on the heads M of the pins. The plate I5 is formed with a pair of lateral ex-r tensions l5 extending transversely of the adjacent edge of the rail 5 and formed at their ends with angular ?anges l1 adapted to engage ‘the side edge of the rail 5. The inner surface of the ex tensions l6 are also formed with serrations or uneven surfaces. An important object of the present invention is to provide a ladder extension of this character teeth It adapted to bite into the edge of the rail. which may be easily and quickly attached in po 10 A U-shaped plate H! has its leg portion recessed sition to either rail of the ladder and which at in the opposite side of the member ‘I ?ush with the same time is strong and durable, relatively the surfaces thereof with the ends of the plate inexpensive to manufacture and otherwise well adapted for the purposes for which the same is intended. I9 projecting outwardly beyond the plate l5 and 15 provided with a pin 20 on which a lever 2| is piv Other objects and advantages reside in the de tails of construction and operation as more fully otally mounted, the lever having a cam head 22 at its pivoted end adapted to bear against the plate l5 to force the same inwardly against the I hereinafter described and claimed, reference member ‘I and with the extension IS in clamping being had to the accompanying drawing forming engagement with the rail 5 as shown in Figure 3 20 part hereof, wherein like numerals refer to like of the drawing. ‘ . parts throughout, and in ‘which: Figure 1 is a fragmentary front elevational view of a ladder showing the extension in posi The lower end of the member 1 is formed with a plurality of transversely extending openings 23 adapted to receive a pin 24 for underlying the rail , 5 to further ‘support the lower end of the rail 5 Figure 2 is a transverse sectional view taken 25 on the extension ‘I. The openings 23 are prefer substantially on a line 2-2 of Figure 3, and ably arranged in vertical rows as shown in Fig Figure 3 is a side elevational view of the exten ure 3 of the drawing with the openings of one broken away and shown in ‘ sion and with parts row staggered with respect to the openings of the other row, the pin 24 being selectively posi section. ' . Referring now to the drawing in detail wherein 30 tioned in the openings of either row in order that for the purpose of illustration I have disclosed a a relatively ?ne adjustment of the member 1 preferred embodiment of the invention, the‘ nu relative to the rail 5 may be obtained. meral 5 designates the pair of side rails of the In the operation of the device when the lever ladder and with the ladder rungs indicated at 6. 2| is moved into its lowermost position, the 35 The extension comprises a short piece of mate clamping plate l5 and extensions it will be pro rial 1 of a cross-sectional area substantially equal jectedoutwardly from the member ‘I by the spring to that of one of the rails 5 and preferably made l2 whereby the extension member 1 may be ad of wood and adapted for placing in facing con justed longitudinally of the rail 5 and the pin tact with the outer surface of one of the rails as 24 is then inserted into one of the openings 23 to 40 shown to advantage in Figure 1 of the drawing. retain, the ladder in its adjusted position. The To one edge of the member 1 is attached a pair lever 2| is then raised upwardly so as to cause tion thereon. ' . of U-shaped plates 8 adapted to receive both the rail 5 and the member 1 within the legs 9 of the plate, the plate ‘being free of the ‘rail 5 and formed at its inner surface with serrations or teeth Ill adapted to bite into the edge of the rail. The oppositeedge of the member ‘I is formed with vertically spaced recesses ll within which l2 are positioned and through which coil springs pins l3 extend with their inner'ends embedded in the member 1 and their outer ends formed with heads l4 spaced outwardly from the adjacent edge the cam 22 to engage theplate l5 and force the same inwardly against the member 1 thereby forcing the extensions 16 inwardly against the rail 5, the plates 8 and the extensions “3 thus cooperating to'clamp the extension member ‘I to the opposite edges of the rail 5. operation and advantages of the device will be readily understood from the foregoing without 50 7 further detailed explanation. of the extension member 1. A clamping plate [5 extends longitudinally I It is believed that the details of construction, along‘the edge of the member ‘I and covers the 55 Having thus described the invention, what I claim is: . ' 1. A ladder extension comprising an elongated 3 2,408,372 member adapted for placing against one side of a ladder rail, a pair of stationary U-shaped clamping plates secured in vertically spaced rela tion to said member and adapted to receive an edge of both the ladder rail and said member for relative sliding movement and to secure the mem ber against lateral movement from the rail as well as against forward or rearward tilting move ment on the rail,v a movable clamping plate car ried ‘by the member; cam means engaging: said movable plate and adapted for moving the mov able clamping plate into clamping engagement with an opposite edge of the ladder rail, and spring means yieldably urging the movable clamping plate out of clamping‘ engagement. 2. A ladder extension comprising an elongated 4 a ladder rail, a pair of stationary U-shaped clamping plates secured in vertically spaced rela tion to said member and adapted to receive an edge of both the ladder rail and said member for relative sliding movement and to secure the mem ber against lateral movement from the rail as well as against forward or rearward tilting move ment on the rail, a pair of pins projecting from a relative opposite edge of the member, a mov~ able clamping plate slidably' mounted en; the pins, cam means‘ carried by the elongated member and adapted for moving the movable clamping plate into clamping engagement with an adjacent edge of. the: ladder rail, and spring means yieldably urging the movable clamping plate out of clampiing engagement. member adapted for placing: against one~ side‘ or - JESSE DE FOREST CHASE.