US2704630A - Step stool - Google Patents

Description

March 22, 1955 B. F. HAMILTON ,6

STEP STQOL Filed May 18, 1950 INVENTOR. finer/s fl -Inna ro/v,

United States Patent STEP STOOL Bertis F. Hamilton, Columbus, Ind.

Application May 18, 1950, Serial No. 162,681

3 Claims. (Cl. 228-30) This invention relates to step stools, or stools having a group of steps mounted in the stool and movable between a retracted position beneath the stool-seat and an extended position in which they provide, in effect, a ladder leading to the stool-seat. It has heretofore been proposed to produce such a stool by connecting the stepassembly with the balance of the stool through the medium of parallel links.

The present invention relates to the type of step stool just described and has for its object to simplify the construction and to lessen the cost of manufacture of step stools. A further object of the invention is to produce a step stool which lends itself to manufacture from sheet metal and metal tubing. Still another object of the in vention is to produce a step stool which will prove sturdy and durable in use.

In carrying out the invention, I employ as a seat for the stool a sheet-metal stamping having a downwardly extending peripheral flange. Two lengths of sheet-metal tubing each bent into a U-shape to provide two generally parallel legs of equal length and an intermediate leg support the seat, the intermediate legs being secured to the seat flange on opposite sides of the seat with the parallel legs extending downwardly. The ladder comprises two similar side members which are formed of metal tubing each bent to provide an upper horizontal portion, a rear vertical portion, a lower horizontal portion, and a front vertical portion. The steps extend between and interconnect the side members, such steps having their ends connected to the horizontal portions of the side members. Parallel links interconnect the upper and lower horizontal portions of the side members with the front legs of the stool and serve to permit movement of the ladder between a retracted position beneath the seat and an extended position. A cross member extending between the two front members of the stool serves to support the ladder in both extended and retracted positions.

The accompanying drawing illustrates the invention: Fig. l is a plan view of the stool with the ladder extended; Fig. 2 is a side elevation of the stool showing the ladder extended in full lines and retracted in dotted lines; and Fig. 3 is a horizontal section on the line 3--3 of Fig. 2.

The stool illustrated in the drawing comprises a seat in the form of a sheet-metal stamping having a downwardly extending peripheral flange 11. To support the seat, I employ two lengths of metal tubing each bent into a general U-shape to provide a front leg 12, an intermediate leg 13, and a rear leg 14. The front and rear legs are generally parallel but may diverge somewhat as indicated in Fig. 2. The intermediate legs 13 of the two lengths of tubing are secured to the peripheral flange 11 at opposite sides of the seat 10 as by bolts 15.

The ladder illustrated in the drawing comprises two side members each formed of metal tubing bent to provide an upper horizontal portion 18, a rear vertical portion 19, a lower horizontal portion 20, and a front vertical portion 21. The upper horizontal portions 18 of the two side members receive between them and support an upper step 22, while the lower horizontal portions 20 receive between them and support a lower step 23. The two steps 22 and 23 are desirably formed as sheet-metal stampings having downwardly projecting peripheral flanges 22' and 23', respectively. To facilitate attach ment of each step to its associated horizontal side portions, the latter may be collapsed to fit against the stepflanges 22' and 23 at the ends of the steps, being secured 2,704,630 Patented Mar. 22, 1955 ice thereto as by means of rivets 24. The lower horizontal portion 20 extends forwardly beyond the upper horizontal so that the lower step 23 is displaced forwardly beyond the upper step 22.

To connect the ladder to the balance of the stool, generally U-shaped yokes or links 26 and 27 are provided. Each of the step-flanges at the end of the step and the adjacent flat portions of the tubular side members are provided with aligned openings which pivotally receive the intermediate portion of the associated link, as indicated in Fig. 3. The front legs 12 are provided on their faces with aligned openings which pivotally receive out-turned ends 28 of each link From the above description it will be apparent that the links 26 and 27 connect the ladder to the front legs 12 of the stool in such a way that the ladder can be moved between the full-line and dotted-line positions shown in Fig. 2, the two links 26 and 27 lying parallel to each other and swinging through arcs of substantially in extent as the ladder moves between two such positions. To support the ladder in both its extended and retracted positions, a cross-brace 30 extends between the two front legs. As shown, the cross brace 30 is of tubular stock having its ends collapsed and bent to provide channel-like sockets 31 in which the front legs 12 may be secured as by means of bolts 32.

The bends which join the lower horizontal portions 20 of the side member respectively with the rear vertical portions 19 are so shaped with relation to the crossmember 30 that with the ladder in extended position those bends will engage the cross-member when the lower ends of the vertical portions 21 engage the floor, thus imparting stability to the extended ladder. The bends which join the horizontal portions 20 with the front vertical portions are so shaped that when the ladder is retracted they will engage the cross-member and hold the ladder at a slightly higher elevation than when extended. As a result, when the ladder is retracted, the lower ends of the vertical portion 21 will be disposed above the floor, as shown in dotted lines in Fig. 2.

The lower ends of the legs 12 and 14 and of the said vertical portions 21 of the side members are desirably provided with domed caps 35 which facilitate movement of the stool over a floor and provide adequate load-transmitting surfaces between the stool and the floor.

In assembling the stool, the steps 22 and 23 are secured to the side members. The rods of which the links 26 and 27 are to be formed are then passed through the aligned holes in the step-flanges and horizontal sidemember portions and bent into the shape shown in Fig. 3. Next, the legs are then brought into association with the ladder, the out-turned ends of the links being received in the holes in the inner sides of the front legs 12, the intermediate legs 13 are secured to the seat flange, and the cross-brace 30 is bolted in place.

I claim as my invention:

1. A step-stool, comprising a seat formed of sheet metal and having integral, depending flanges at opposite sides, a pair of leg members each comprising a length of metal tubing bent into an inverted U-shape to provide front and rear seat-supporting legs and an intermediate portion, the intermediate portions of said leg-member portions being secured to said seat-flanges, a ladder, a pair of vertically spaced link members interconnecting said ladder with said front legs, each of said link members being of a general U-shape and having an intermediate portion pivotally connected to said ladder, the ends of each link member being bent outwardly into aligned relationship, said front legs being provided in their inner sides with holes pivotally receiving said link-ends, and a cross-brace extending between and secured to said front legs for supporting said ladder in retracted an extended positions and for holding said leg members in fixed relative position, said cross-brace having at each end a leg-receiving seat extending longitudinally of the leg.

2. A step stool, comprising a seat, front and rear seatsupporting legs, a ladder, said ladder including a pair of side members each formed of metal tubing bent to provide an upper horizontal portion, a rear vertical portion, a lower-horizontal portion, and a front vertical portion, an upper step having end flanges fitting against and secured to the inner sides of the upper horizontal sidemember portions, a lower step having end flanges fitting against and secured to the inner sides of the lower horizontal side-member portions, said horizontal portions being collapsed over the extent of said end flanges, said horizontal side-member portions being provided with openings, link members pivotally received in said openings and pivotally connected to said front legs to guide and support the ladder between extended and retracted positions and a cross-member extending between said front legs for supporting the ladder in its extended position.

3. A step stool, comprising a seat, front and rear seat-supporting legs, a ladder, said ladder including a pair of side members each formed of metal tubing bent to provide an upper horizontal portion, a rear vertical portion, a lower horizontal portion, and a front vertical portion, an upper step having end flanges fitting against and secured to the inner sides of the upper horizontal sidemember portions, a lower step having end flanges fitting against and secured to the inner sides of the lower horizontal side member portions, said horizontal side-member portions being provided with openings, link members pivotally received in said openings and pivotally connected to said front legs to guide and support the ladder between extended and retracted positions, and a crossmember extending between said front legs for supporting the ladder in its extended position.

References Cited in the file of this patent UNITED STATES PATENTS 1,797,656 Hall Mar. 24, 1931 2,400,779 Pearle May 21, 1946 2,453,090 Guild et al. Nov. 2, 1948 2,458,890 Booth Jan. 11, 1949 2,525,126 Greitzer Oct. 10, 1950

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