Folding step stool

#Step stools are commonly employed for both household and industrial purposes to reach articles or otherwise perform work at a height above the normal safe reach. According to the prior art, such step stools may be a fixed configuration having one or more steps. Such fixed step stools are bulky and are not easily stored when not in use. No handgrip is provided above the level of the top step to stabilize the person utilizing the step stool when ascending, descending and reaching from the top step of the step stool.

#Folding step stools are also known. According to one popular design, a step stool incorporates two folding steps carried between a first U-shaped member and pivoting legs. When in the extended position, both U-shaped member and legs are at an angle with respect to the floor and pivotally engage the floor with rubber crutch tip terminations. Such step stools are not self-supporting when retracted. The U-shaped member does form a crosspiece above the level of the highest step; however, the crosspiece is generally no more than one step-to-step vertical distance above the highest step and therefore is not useful as a handgrip when ascending, descending or standing upon the highest step. Because both the U-shaped member and the legs are at an angle, it is not possible to move such a step stool directly against a vertical surface and therefore the person utilizing the step stool must lean toward the vertical surface to reach, requiring a precarious balancing.

#It is therefore desirable to have a step stool which combines the features of foldability with an effective handgrip. Such a step stool is particularly desirable where it may be utilized closely against vertical surfaces, and is self-supporting and compact in the folded position.

#FIG. 1 is a perspective view of the step stool in the extended position.

#FIG. 2 is a perspective view of the structure in the retracted position.

#FIG. 3 is a elevational view of the step stool in the extended position, with portions cut away.

#Referring to the drawings, there is illustrated a frame 10 having a floor engaging lower terminus in the form of a base 20. The base provides a substantial horizontal surface for engagement with the floor and a steady base for the step stool in both the extended and the retracted positions. Uprights 22 and 24 extend vertically from the base and support the folding step legs and handgrip as is described more fully hereinafter. A handgrip 26 is secured between the uprights 22 and 24 at their upper terminus and forms an additional frame member, stiffening the frame in addition to functioning as a handgrip for a person ascending and descending the stool. The handgrip is 28 inches above the highest step, step 16. Additional stiffening and longitudinal rigidity for the frame is provided by cross braces 28. A pair of slots are located in the rear one-half of the width of the upright (the side opposite the side from which the legs extend). The slots extend vertically a sufficient distance to accommodate the travel of the upper portion of the legs during folding as described hereinafter.

#A dowel 34 is carried in the slots 30 and 32 for a combination of translation and rotation during the folding action. The frame 10 also carries a dowel 36 which is received in bores through the uprights 22 and 24 positioned in the rearward one-half of the horizontal width of the uprights. A pair of legs 12 and 14 are secured to the uprights by the dowel 34 being received through the upper extremities of the legs. A platform step 16 is secured to the uprights in a pivoting connection to the dowel 36. The legs 12 and 14 are braced by cross brace 44, mounted below the dowel 34, and the step brace 18 received in slots in the legs 12 and 14 and positioned to be horizontal when the legs are extended. Dowel 38 extends between the legs 12 and 14 intermediate the step brace 18 and cross brace 44. The platform-step 16 is carried pivotally on the legs by dowels 38. The platform-step 16 is horizontal in the extended position of the legs. Loads on the platform-step 16 are transmitted to the dowels 36 and 38 near the point where the dowels enter the legs and uprights, respectively, so that relatively low bending forces are created. The force is concentrated near the ends of the dowels through the use of strips 40 which also serve to mount the pivot brackets 42.

#Referring to FIG. 2, the folded or retracted position of the step stool is illustrated. When folded, the dowel 34 has been translated from the position at the lower extremities of slots 30 and 32 to a position at the upper extremities of slots 30 and 32. The legs 12 and 14 are limited in their folding action by contact with the dowel 36. However, by placement of the dowel 36 in the rearward one-half of the width of uprights 22 and 24, the folding actions proceed to the point where the lower extremities of the legs lie within the vertical projection of the base 20. Since the slots 30 and 32 are also within the rearward one-half, the center of gravity of the entire combination lies above the base 20 so that the step stool will stand by itself without the need for leaning against any vertical surface. The positioning of the center of gravity is also favorably affected by the use of the strips 40 which place the seat further within the vertical projection of base 20 when the legs are folded.