US2396813A - Ladder - Google Patents

Description

, a supporting leg and used Patented Mar. 19, 1946 UNITED STATES PATENT OFFICE 2,396,813 LADDER Frank J. Benz, Morgan Hill, Calif. Application June 12, 1944, Serial No. 539,894

(01. 228-63) The present invention relates to ladders and 1 Claim.

more particularly to that form of ladder having for the picking of fruit in an orchard.

The stiles and leg of the ladder have hereto fore been of fixed length, and consequently it has been difficult if not impossible to properly place the ladder in position for picking where the trees are growing on a side hill, or where the land is otherwise than level.

It is, therefore, the object of my invention to provide a ladder wherein a stile or leg, if the ladder has a supporting leg, may be adjusted as to length to accommodate it to any inequality in the surface of the land on which it is .to be placed, and to provide an adjustment means that may readily be applied to an existing ladder and that willbe simple in form and construction, economical to manufacture, quickly and easily operated by the party handling the ladder, strong, durable. and highly efiicient in its practical application.

In the drawings:

Figure 1 is a front elevational view of a ladder embodying my invention in one stile.

Figure 2 is a side elevational view of a ladder embodying my invention in its supporting leg.

Figure 3 is an enlarged detail sectional View on line 3-3 of Figure 2.

Figure 4 is an enlarged elevational view of a portion of the side of the ladder leg as indicated at 4--4 of Figure 2.

Figure 5 is an inside elevational view of the same.

Figure 6 is a sectional view on line 5-6 of Figure 4.

Figure 7 is a perspective illustration of a portion of the leg controlling mechanism.

Figure 8 is a perspective view of the lever for operating the leg controlling mechanism.

In the particular embodiment of the invention herein disclosed, I show at I a ladder having the bottom end of one stile removed up to the bottom of the first step 2 as indicated at 3 and replaced with an adjustable stile portion 4 slidably mounted on the side of the ladder as shown in guide 5 and guide 6. Guide 5 is fixedly mounted on the ladder, but guide 6 is pivotally mounted thereon as at I. Th guide 6 has a pin 8 passing therethrough in parallel relation to the pivot pin I, and a dog 9 is pivotally mounted thereon as shown. The dog 9 is in the form of a bell crank, one end extending downwardly over the ladder stile where it may be easily engaged by a finger of the operator and the other end being slightly longer than the distance between the pin 8 and the facing surface of the stile so that any force urging the stile portion 4 to move in the direction of the arrow I0 relative to the ladde I will force the dog to more tightly bite into the part 4 and immovably bind it to the ladder I. By relieving the pressure and lifting up on the downwardly extending portion I I of the dog 9 the stile engaging end I2 may be disengaged and the stile portion 4 moved to any desired position relative to the ladder where it may be locked securely by the means described.

By equipping the two side stiles of a ladder as described it may be readily adjusted to maintain a vertical position insofar as lateral tipping is concerned regardless of the contour of the land.

Certain other conditions, such as that hown in Figure 2, are met by slidably mounting an extension leg I3 on the ladder leg I4, and controlling its adjustment in the following manner.

On the lower end of the ladde leg I4 is mounted a fixed guide member I5, and spaced upwardly from the member I5 is a guide I 6 pivotally mounted on leg I4 a at IT. When the member I6 is in contact with the extension I3 any force tending to urge the extension upwardly as indicated by the arrow in Fig. 4 also tends to swing the member I6 further about its pivotal point I1 and causes it to more tightly grip the extension I 3 and prevent its movement. The membe I6 is normally held in contact with the extension leg I3 by a spring I8 in groove I9 connected at one end to a pin 20 and at the other end to a pair of levers 2| pivoted at 22 and having outer ends 23 engaging slot as 24 in member I6, and operating to force the upper edge of member I6 upwardly into contact with extension leg I3.

In order tomove the extension I3 relative to the leg I4 it is necessary to swing the member I6 backwardly on its pivot I I, and this is accomplished in the following manner.

A wire 25 is attached at one end to the levers 2| and at the other end to a lug 25a projecting outwardly from the central part of rod 26 at the top of the ladder and forming a part of its normal construction. By turning the rod in a clockwise direction the pull of spring I8 is counteracted and the member I6 is swung away from contact with extension I3 permitting said extension to slide in either direction on leg I4.

The rod 26 is turned by the operator of the ladder through the medium of a wire 26a having one end attached to an arm 21 on the end of rod 26 and having its other end attached to a lever 28 pivotally mounted on the ladder at 23. By raising the longer arm of the lever at 30 it is caused to lace the wire 26a under tension and turn rod 25 with the result described. When the extension [3 is free to slide it may be allowed to slide down by gravity to some such position as shown in Figure 2, or the weight of the ladder may be allowed to force the extension 13 upwardly to some desired point. This adjustment may be effected by the user of the ladder since he may operate the lever 30 when he desires to alter the length of: the leg.

While the wire 25 operates in a groove IS, the wire 26a operates in a groove 3| in the inner side of the stile on which the lever 28 is mounted. These grooves are provided for the wires so that they will not become entangled in the branches of the tree in which the ladder may be placed.

In the following claim the; word .leg is intended to mean either stile or the supporting member pivoted to the top of the ladder at 32.

Having thus described my invention, what I 20 .,connecting the clamping means and rotatable rod operative to move the clamping means out of engagement with the extension member when the rod is rotated, and manually operated means for rotating said rod connected to said rod at one end-and having its other end terminating at a point on the ladder adjacent its lower end.

FRANK, J. BENZ.

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