US3085651A - Step ladder - Google Patents

Description

April 16, 1963 H. B. RICH STEP LADDER 'Filed June 3, 1960 INVENTOR. HOWARD B .RICH

ATTORNEYS 3,085,651 STEP LADDER Howard B. Rich, Carroilton, Ky., assignor to Howard B. Rich, Ina, Carroilton, Ky., a corporation of Kentucky Filed June 3, 1960, Ser. No. 33,684 1 Claim. (til. l82222) This invention relates to stepladders and to a step con struction for a stepladder.

An object of this invention is to provide a sturdy, light weight, rigid step construction for a stepladder.

A further object of this invention is to provide a ladder having wood side rails and strong, sturdy steps of extruded metal so constructed that the steps are safely and strongly secured to the side rails and in which the securing means which attaches the steps to the side rails serves to support the steps.

A further object of this invention is to provide a step construction for a stepladder of this type having a tread portion on the lower face of which are mounted elongated flanges which eXtend downwardly along opposite lengthwise edges thereof and in which the lower edge of each flange is divided into lengthwise bifurcations which engage and embrace tension rods, there being a tension rod for each flange, the tension rods linking the side rails of the ladder so that the tension rods underlie and support the flanges and support the steps.

The above and other objects and features of the invention will be apparent to those skilled in the art to which this invention pertains from the following detailed description and drawing, in which:

FIG. 1 is a perspective view of a stepladder constructed in accordance with an embodiment of this invention;

FIG. 2 is an enlarged perspective view showing a portion of one side rail and one step;

FIG. 3 is a view in section taken on the line 33 in FIG. 2, showing the step in transverse section, the step being removed from the ladder.

In FIG. 1 of the drawing is shown a collapsible stepladder 11 having side rails 2 and 3 hinge-connected at their upper ends to brace or stay legs 4 and 5. The upper end of the ladder is provided with a platform 6. The stay legs 4 and 5 are provided with cross braces 8 and 9. The rails 2 and 3 are connected to the stay legs 4 and 5 by means of braces 10 and 11 which may be of usual construction. As shown, each of the braces 19 and 11 comprises links 12 and 13 which are hinged at 14 and 15 to the side rails and stay legs as shown. Adjacent ends of the links are hinged together, as at 16.

The ladder is provided with steps 18, the construction of which is more particularly shown in FIGS. 2 and 3.

Each tread or step is formed of rigid extruded metal, such as aluminum or the like, and is provided with a relatively broad tread portion 19 having downwardly projecting deep edge flanges 2t and 21 along opposite edges thereof.

The tread portion 19 may be provided with ribs 22 which serve to strengthen the step and prevent slippage when a person stands on the step.

As shown most clearly in FIG. 3, the lower portion of the deep edge flange terminates in bifurcations 23 and 24. Similarly, the deep edge flange 21 terminates in bifurcations 26 and 28. As shown, the bifurcations are curved so that, as shown in FIG. 2, each set of bifurca- 3,085,651 Patented Apr. 16, 1963 tions is adapted to receive and embrace a tension or tie rod, the bifurcations 23 and 24 receiving a tie rod 31 and bifurcations 26 and 28 receiving a tie rod 32. As shown in FIGS. 1 and 2, the tie rods extend through the side rails 2 and 3. The side rails can be formed of wood or other suitable material. Each end of each tie rod carries a washer 34 and a nut 36, threaded on the tie rod. The washers engage outer faces of the side rails 2 and 3 so that, when the nuts 36 are tightened, the side rails are drawn and compressed against ends of the steps. As shown most clearly in FIGS. 1 and 2, the deep edge flanges 2t) and 21 form edge faces for the steps and conceal the tie rods.

The tie rods 31 and 32 may be formed of steel wire or the like. The tie rods underlie and serve to support the deep edge flanges, and, in turn, the deep edge flanges support the tread portion of the steps.

The stepladder construction illustrated in the drawing and described above is subject to structural modification without departing from the spirit and scope of the appended claim.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

A ladder construction comprising a pair of side rails, a plurality of spaced, parallel, rigid step members spanning said rails, each of said step members including a flat tread portion having parallel edges and downwardly depending front and rear flanges contiguous with said tread portion from end-to-end between said side rails at the parallel edges of said tread portion, the front flange being unobstructed and perpendicular to said tread portion, the rear flange being substantially perpendicular thereto, said flanges each terminating in a bifurcated edge ,the bifurcations at each edge being of arcuate, complementary shape having spaced apart terminal edges and defining an elongated tubular passage at each lower edge of each depending flange, a pair of tension rods engaging each side rail and disposed within each elongated tubular passage to hold the side rails in tight engagement with each end of each of the step members, said elongated passages being so formed as to closely and irreleasably engage said tension rods whereby said tension rods reinforce said flanges and, simultaneously, said tension rods are prevented from flexing due to loads imposed on said step member, said tread portion, said downwardly disposed flanges and said bifurcated ends of said flanges being formed integrally as a rigid, one piece, extruded metal section.

References (Iited in the file of this patent UNITED STATES PATENTS 652,010 Wheeler June '19, 1900 1,087,878 Harrah Feb. 17, 1914 2,265,735 Lambert Dec. 9, 1941 2,485,165 Pollman W Oct. 18, 1949 2,488,633 Linder et al. Nov. 22, 1949 2,606,079 White Aug. 5, 1952 2,844,292 Rich July 22, 1958 2,963,761 Haydock Dec. 13, 1960 FOREIGN PATENTS 789,998 France Sept. 2, 1935 139,644 Australia Dec. 7, 1950

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