US1633902A - Stepladder - Google Patents

Description

June 28, 1927. 1,633,902

- G. E. OLSON ET AL STEPLADDER Filed Sept. 20, 1926 INVENTOR I f M M 6 my. 3 W ATTORNEY L Patented June 28, 1927.

- UNITED STATES PATENT 0 Gus E. OLSON Am) ALFRED :r. WILLIAMS, or SEATTLE, wasnme'ron; SAID wILLIAJks' -ASSIGNOR, BY mnsnn ASSIGNMENTS, 'ro DANIEL o. OLSON, or. SEATTLE, WASH INGTON.

STEPLADDEEB.

Application filed September 20,1926. serial no. 136,468.

This invention relates to improvements in step ladders and the object of this invention is to provide a step ladder that may be opened into an extended position by placing the foot .on a step of the ladder and exerting a downward pressure thereon.

Another object is to providg a step ladder in which the weight of a person on the steps will always keep the legs of the ladderextended and open even though; said legs may be raised from the support on which they rest.

der in which the side supports of the ladder proper are each formed of two parallel bars or members to each of which each step is pivotally connected at both ends and in which the upper ends of the legv members of the ladder are also pivoted to said two side bars in such a manner as to cause the bottoms of said leg members to be moved out ward-1y in response to pressure on the steps, the bottom end of the forward bar of each leg member being cut short so that it will ordinarily be clear of the supporting sur-v face on which the ladder rests.

Another object is to provide a step ladder of this nature in which the steps are always automatically maintained in a horizontal position.

Further objects are to provide a step ladder of this nature that is simple in design, strong and substantial in construction, not expensive to manufacture and free from operating parts that might tend to get out of order.

Other .and more specific objects will be apparent from the following description taken in connection with the accompanying drawings wherein Figure 1 is a view in side elevation of a step ladder constructed in accordance with this invention showing the same in an open position.

Fig. 2 is a similar view showing the step ladder in a closed or folded position.

Fig. 3 is a view in front elevation of the step ladder as it may appear when open or extended. 1

Figs. 4: and 5 are fragmentary views in side elevation respectively on a larger scale showing the top end of the ladder in an A further object is to provide astep lad-v ;of strong 7 rivets 24L to the sides of rt hebars 6 and 'Tiand ter illustrate the parts underneath said leg.

member. v

Referring :to the drawings, throughout whichJlike reference numerals designate like parts, 6 and 7 designate two substantially parallel bars that form the side memberson each side of a ladder. 8 designates .a top step having an angle bracket 10.near each end on its bottom side which angle brackets .are: each pivotally connected by pivots 11 and 12 with the respective top ends of they bars 6 and 7 that form the adjacent side of the ladder. 13 are lower steps or treads provided near their ends with angle brackets 14 that are each pivotally connected with FiFlC-B- the bars 6 by pivots 1-5 and with the bars 7 f by pivots 1 The leg portion of the stepiladderfcoln' prises two leg members. 17 and 1 8,-one at each side of said step ladder, that are con nected with each other by conventional cross braces 20 .at the back and that are each con-" nected at the top end with theadjacentside members 6 by a pivot 21 and with the other ad acent side member 7 "by apivoit 22. Suitable'reinfoncing plates 23 preferably sheet metal may ibe. secured by to the sides of the leg members 17 and to form solid wear resistant, noi-isplitting parts through which the pivots 11,12,- 21

and 22 may extend.

The metal contact plates or stop members 25 are secured to the adjacent edges of the respective bars 6 and .7 near their top ends and are adapted to abut when the step ladder is in the open or operative position.

The operation of this step ladder is as follows:

When the step ladder is in the folded or inoperative position and it is desired to open' or extend the same the ends of the side bars -6 are placed on a support, as the floor, and

the foot is placed on one of the steps 13, preferably the lowermost and'a downward pressure is exerted. This downward pressure tends to move the front bars 7 downardly and the consequent link action be tween pivots 11. and 12 at the top and respective pivots 15 and 16 at the ends of the steps causes said bars 6 and 7 on each sideto be drawn closer together. This same movedownward relative to the leg pivots 21 and by exerting a torque in the region of said ment necessarily moves the leg pivots 22 V pivots 22 and 21 moves the bottom ends of the leg members 17 and 18 outward. This outward movement of the bottoms of theleg members 17 and 18 is limited by engagement ofthe adjacent edges of the side bars 6 and 7. As the bars 7 move downwardly relative to the bars 6 and the leg members 17 and 18 swing outwardy into operative position the lower steps 13 and the top step or platform 8 are moved into horizontal positions. 7

It will be noted from Figs. 1, 2, 4 and 5 that the pivots 21 and 22 are substantially opposite each other in a plane approximately parallel with the plane of the top step 8 when the step ladder is completely folded, as shown in Figs. 2 and 5, and that the pivot 22 swings downwardly relative to the pivot 21 when the step ladder is opened or extended. It will also be noted that the pivots 21 and 22 are closer together than the pivots 11 and 12. w

The lower ends of the front bars 7 do'not rest on the supporting surface at any time and consequently the weight of a person on the steps of the ladder will always hold said bars 7 down and thereby hold the bottom ends of the legs 17 outward. This makes it impossible for the step ladder to close while a person is on it if the person on the ladder tilts the same in such a manner as to raise the bottom ends of the legs from the supporting surface.

The step ladder may be folded in the usual manner by moving the ladder portion and the leg portion. The folding of the ladder moves the bars 7 upwardly relative to the bars 6, and, at the same time incidentallymoves said bars apart leaving the ladder in condition to be opened by downward pressure on any of the steps.

ladder.

The side members 6 function as supports proper for the steps and the bars 7 function as the actuatin means for opening the The bars 7 however rest against the bars 6 at least at their tops and bottoms when the ladder is extended and ,itheir strength is thus combined with the strength of the bars 6 and utilized fully in forming a strong side supporting structure for the step portion of the ladder.

The ladder is strong and substantial in construction, neat and attractive in appear ance and is very easy to open, it being possible for a person to open the ladder with one hand and foot while the other hand is otherwise occupied.

The foregoing description and accompanying drawings clearly disclose a preferred embodiment of this invention but it will be understood that this disclosure is merely illustrative and that such changes in the device may be resorted to as are within the scope and spirit of the following claim.

What we claim: I

A step ladder embodying two spaced side members each formed of two relatively movable parallel bars, a transverse step pivotally connected near each end with each adjacent side bar and two leg members each connected at its upper end by two pivots with the adjacent two side bars said two bars at each side being relatively close together when said leg members are folded and being in edge to edge contact when the leg members are fully extended.

In witness whereof, we hereunto sub-' scribe our names this 9th day of September ALFRED J. WILLIAMS. GUS E. OLSON.

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