US2444384A - Ladder leveling device - Google Patents

Description

v Patented June 29, 1948 UNITED STAT LADDER LEVELING DEVICE Herman C. Thi, Atlanta, Ga. I ApplicatioriMar'ch so, 1945,'S erial No. 585,615

3 Claims. (CL 228-433) This invention relates to ladders and more particularly to an extension device adapted to be used with either straight ladders or so-called stepladders of the self-supporting type and of such a construction that it'can' be'used singly witha single leg of a ladder or, if preferred, in connection with both legs and by means of which the length of the respective ladder legs can be varied as desired toconform with the contour of the ground or other surface upon which the ladder is positioned.

An object of the present invention is to provide an extension device of the character. indi cated which is easily applied'to anystandard makeladder and which can be manipulated with the use of a, foot, thus eliminating any necessity to bendor use the hands, so that the device can b..easilyand safely operated by a single person while controlling the ladder. j I

Other objects will more-particularly appear in the course of the following detailed description.

The invention consists in the novel construction, arrangement and combinations of parts hereinafter more particularly described and claimed.

or medial portion lprovided with a plurality of aligned holes I5 adapted to be selectively engaged with a stud I4 herein illustrated as a screw imbedded in the ladder leg I and projecting from the rear edge thereof. 1

'Atension spring I2 connects a lip II formed on theupper end of thechannel member 3 to the ladder leg I substantially above the normal position of the channel member so asto tend normally to pullthe channel member into its upper and retracted positionon the leg.

One sheet of drawings accompanies this speoification as part thereof, in which like reference characters indicate like parts throughout.

In the drawings:

Figure 1 is a perspective view of the lower end of a ladder showing the present invention applied to each of the legs;

Figure 2 is a perspective view of a stepladder showing the present invention applied to each of the front ladder legs;

Figure 3 is a medial cross-section through the present invention as applied to a ladder leg;

Figure 4 is a side elevation of the lower end of a ladder leg with the present invention in position;

Figure 5 is a transverse cross-section taken on line 5-5 of Figure 2; and

Figure 6 is a transverse cross-section taken on line 6--6 of Figure 3.

Referring to the drawings, the device of the present invention is adapted to be used in connection with either a straight ladder as illustrated in Figure 1 or a step-ladder as illustrated in Figure 2, in connection with either of which ladders the legs are identified by the reference I and the rungs by the reference 2.

To increase the length as desired of either of the ladder legs I a chanel-shaped sleeve member 3 is provided adapted to slidably embrace the lower end of the ladder leg I and having its back The sides of the channel member 3 are bridged adjacent the top by a bridgemember 5 to which is secured as by bolts or rivets! a resilient tongue 6 the ends of which are arranged to press against the forward edge of'the ladder leg I. I

Secured to the bottom of the channel member as by'transverse rivets or bolts 9 is a foot piece 8 adapted to constitute the ground-contacting portion where the ladder is used on a hard surface. F v I For situations where the ladder is to be used on the earth, a spur member I6 having aligned guide slots I I is slidably secured to one ofthe side walls of the channel member 3 as by a rivet or bolt I0 passing through the channel member and the foot piece 8 and by a bolt carrying a wing nut I8 extending through the upper slot I1 and the adjacent wall of the channel member. The lower end of the slide member I6 will be pointed as at 20 to readily penetrate the earth, and the I slide is provided with a foot-engaging flange I9 by means of which it can be readily lowered into operative position.

With the structure as thus described, it being desired to lengthen one or the other of legs I of the ladder, the foot will be applied to the foot member 8, rocking the channel member 3 rearwardly against the tension of the leaf spring 6, thus disengaging the stud I4 from one of the holes I5 in the rear wall of the channel member 3 and further pressure downward on the foot piece 8 lowers the channel member against the tension of spring I2 to the desired distance below the bottom of ladder leg I whereupon the removal of the foot from the foot member. 8 permits the channel member under the tension 01' leaf spring 6 to resume its normal position in alignment with the ladder leg I and permitting the stud I4 to reengage the adjacent hole I5 thus securely locking the channel member 3 in its lowered position. To shorten the ladder leg I the channel member is similarly rocked by the application of the foot pressure on the member 3 but upon release of the pressure and while holdsupporting leg and a-bolt- 25 extending from the: supporting leg Lit-through a slot 23' provided inthe extension part adjacent its upper end. To assure a positive grip between these two members short lengths of transversely corrugateds-trips 26-21 are secured to the con-fronting faces of the supporting leg 30 and extension 22 as by screws 28. When the thumb nut 29 .isretracted upon bolt 25 the extension member 22 can be adjusted up or down on the supporting legs-in and A relocked into positive association with said leg by thettightening of the nut, thusdrawing the corrugated members 26-21 into. locking engagementas is well illustrated in Figure-5.

Various modifications in the construction and arrangement of the parts as wellas their proportionslwill readily suggest. themselvesto those skilled in the art to readily adapt the same to any stahdard, type t of ladders.

Having thus described my invention, 1 claim:

1. Extension device for ladders comprising a collar adapted. to slidably embrace the leg oi a ladder tension means arranged tonormally draw the collar, upwardly on theleg, interengaging memb.erszon.one. face oi the collar, and theiadjacent-face of the leg,.tension means on the opposite face of the collar adjacent its toptadapted to en.- a e'tthe adjacent-face L theleg, foot'engaging meanscarried by -the bottom part of the-collar; that face of the collar carrying the legengaging tension means being cut awayato permit the rocking of the collar against said tension means tocreleasethe interengaging members.

2. Extension device for ladders comprising a member of channel cross-section adapted to embrace the ladder leg, the sides of said member bridged at the upper end, a resilient member mounted on the bridging part to engage the exposed edge of a ladder leg positioned in the said channel member, interengag-ing members on the opposite edge of the ladder leg and the medial part of the channel member, spring means connecting; the upper partr of the: channel member tothe ladder leg, afoot engaging part onthe bottom of the channel member and a spur member slidingly mounted on the channel member with meansfor securing the spur in adjusted position.

3. Extension device for ladders comprising a collaradapted to slidably embrace the leg of a ladder and to rock with respect to said leg, interengaging members on one face of the collar and the adjacent face of the le tension means operative to normally rock the collar into alignment with the leg and the .interengaging members into engagement, tension. means operative normallyto slide the collar upwardly on the leg, and a foot carried by the collar having a part arranged'to be engaged bythe foot of an operator to rock the collar with respect to the ladder leg to disengage the inter-engaging members and permit sliding of the collarlengthwise with respect to theleg.

. HERMAN C. THIE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 854,152 DeCook May 21, 1907 1,513,854 Pettiford -7 Nov. 4, 1924' 2,107,629 Dallas Feb; 8, 1938

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