US3498409A - Portable climbing step for climbing trees or poles - Google Patents

Description

L. S. MEYER March 3, 1970 PORTABLE CLIMBING STEP FOR CLIMBING TREES OR POLES Eiled March 5 1959 INVENTOR. L EONARD S. MEYER [X j BY [5 m. R N a R R O E T LQT M/A M. Y Y B M United States Patent US. Cl. 18292 Claims ABSTRACT OF THE DISCLOSURE A portable tree climbing step of crank or L-shape which can be removably secured to poles or trees by means of standard lag screws or bolts.

BACKGROUND OF THE INVENTION Various portable or removable steps for climbing trees or posts have been designed and used in the prior art. They usually are L-shaped units and have a screw integral or rigidly fastened to and projecting from one end of the support arm thereof, the crank-shaped step and support arm being used in turning the screw into the post or tree trunk. The crank-shaped step and support are commonly formed by expensive processes and ones which detract from the strength of the material used. Also, when removing the prior art step units, it is common to break or bend the screw. Furthermore, the screw commonly becomes bent in use, especially in a live tree. This makes it necessary to discard the entire step unit often after it is used only once.

The present invention overcomes all of the above-indicated disadvantages as will appear from the following description.

In the accompanying drawing, I have illustrated a preferred form of detachable step embodying the principles of my invention and in this drawing:

FIGURE 1 is a perspective view showing one of the steps applied to a tree trunk.

FIGURE 2 is a side elevational view showing the step and a detached lag screw associated therewith.

FIGURE 3 is an elevational view taken at a right angle to that of FIGURE 2.

FIGURE 4 is a schematic view illustrating how blanks.

for forming the steps can be cut from a simple flat bar of stock.

With reference to the drawing I have illustrated, the step of this invention as comprising a one-piece L-shaped unit which includes a normally vertical or upright support crank portion 11 and an outwardly extending substantially horizontally disposed step portion 12. The unit is made from flat steel bar stock and it will be noted that the portion 11 is joined to the portion 12 by a twisted angle portion 13-. This results in positioning the step portion 12 upright edgewise in a vertical plane which is at a right angle to the flat vertical plane of the upright crank portion 11. The result is greatly increased strength at the angle than would otherwise be obtained by a flat bend instead of a twisted bend between the two portions 11 and 12. This results not only in an increased strength in the angle, but also, since the step portion 12 is disposed edgewise upright, the inherent strength of the step portion itself is increased.

It will be noted that the top end of the crank portion 11 is provided with a point 14 which results from the tapered upper end 15 of the portion. Also, the outer end of the step portion 12 is tapered or angled as indicated at 16 which also provides a point. These tapered ends result from the cutting of the bar stock used in forming the units as will be explained later.

As indicated above, the step portion 12 is substantial- Patented Mar. 3, 1970 1y horizontal in normal usage. However, the angle :bend is such that the included angle between the portions 11 and 12 is less than so that the step portion 12 is inclined downwardly-toward the upright portion 11, so that when a foot is supported on the portion 12, it will tend to slide inwardly towards the upright portion. This is a desirable safety factor.

For attaching the unit to a tree or pole T, indicated schematically in FIGURE 1, a lag screw or bolt 20 is used. This screw may be of the standard type having a square or angular head 21. The upright crank 11 is provided with an opening 22 adjacent its upper end through which the shank of the screw is adapted to extend. Around this opening in the outer surface of the portion 11, a notch or socket 23 is provided for receiving the head 21 of the screw, when the shank of the screw is positioned in the opening 22 and moved inwardly as far as possible. It will be noted that this socket extends transversely completely across the portion 11 and provides straight upper and lower shoulders 24 which will engage opposed upper and lower edges of the head 21 to prevent rotation of the screw relative to the crank portion.

In use, the screw is opsitioned in the portion 11 as indicated and the unit may be used as a crank for screwing the screw into the tree trunk or pole. Starting of the screw may be aided by forcing the point 14 into the tree trunk to provide a starting hole for the screw. However, the point at the end of step portion 12 could be used as a starting point. Removal of the step unit can be readily accomplished by a reverse crank rotation.

The unit can be made by a simple process from standard bar stock indicated at B in FIGURE 4. Angular cuts at 15 and 16 will produce a blank of proper length from the metal stock points at both ends. Then it is merely necessary to twist and bend the blank to form the L-shaped unit, as indicated. Either before or after the blank is produced, the openings 22 and sockets 23 may be formed at proper longitudinal intervals. Thus, the units can be produced economically with the desirable strength and safety characteristics.

Because the units use standard screws which are detachable, as the means for removably securing them to the tree trunk or pole, many advantages are obtained. One of the advantages is the simplicity in production, since it is not necessary to form the screw integral with the rest of the unit by expensive processes which also detract from the strength of the unit or to rigidly attach the screws to the units by time-consuming processes. Also, with this arrangement, it is possible to select the type of screw suitable to the particular tree depending upon whether it is hard or soft wood. The choice of screw length can influence safety, as obviously, a screw too short can pull out. A screw too long would be more difficult to screw into a tree, especially if it is a hardwood, and also more difficult to remove. Furthermore, broken screws or bent screws can be readily replaced in the field. Broken screws are common when, and as, the step is removed, especially after a day or two in a live tree. Furthermore, any screw disposed on the unit in an over-hanging cantilevered condition will bend when the step is used. Once bent, the screw becomes very difficult to thread into the next tree and, if straightened, is subject to failure caused by metal fatigue. From a safety standpoint, such metal fatigue is especially dangerous because the shank can be cracked and apparently safe, whereas it could fail without warning. Because of the design of the units they will be relatively lightweight, which is important when a number of them are to be carried into remote .areas.

Having thus described this invention, what is claimed is:

1. A portable step unit comprising a body of substantially L-formation with the upright portion serving for attachment to a tree or pole and with the outwardly extending portion serving as a step, said upright portion having an opening extending therethrough and a socket at the outer side thereof around the opening, said socket being of angular form for receiving an angular head on a screw having its shank positioned in said opening so that the socket cooperates with the head to prevent rotation of the screw.

2. A portable step unit according to claim 1 in which the step portion is joined to the upright portion at an angle less than 90 so that the step portion inclines downwardly toward the upright portion.

3. A portable step unit according to claim 2 in which at least One end of the L-shaped body is pointed.

4. A portable step unit according to claimv 1 in which the body is'made of'one piece of fiat metal bar stock which is bent and twisted at the angle between the upright portion and the step portion so that the step portion References Cited UNITED STATES PATENTS 1/1967 Bergsten 182-9 2 4/1968 Melcher "182-92 REINALDO P. MACHADO, Primary Examiner US. Cl. X.R. 2482l6

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