US3356180A - Tripod stepladder - Google Patents

Description

Dec. 5, 1967 R D, PARRY 3,356,180

TRIPOD STEPLADDER Filed July 15, 1966 United States Patent O 3,356,180 TRIPOD STEPLADDER Robert D. Parry, 7240 Algonquin Drive, Cincinnati, Ohio 45243 Filed July 13, 1966, Ser. No. 564,986 1 Claim. (Cl. 182-124) This invention relates to stepladders and, more particularly, this invention relates to a stepladder of the tripod type that is particularly adapted for use in corners.

There are many different types of stepladders known in the prior art. Yet, for all the improvements in known types of stepladders, they, with few exceptions, have been provided with four support points, i.e., four legs have been provided to support the stepladder when it is in the open or use position. The four support points generally have been thought necessary to maintain stability in the ladder when it is being used. However, a ladder with four support points or legs is relatively difficult to use in corners, e.g., corners of a room inside the home. Such corner use by prior art stepladders is made difficult because the user usually wants to be relatively close to the wall. Because of the location of the four support points on the typical prior art type of stepladders, however, they cannot be positioned near enough to the corner so that the user may easily work in the corner at elevated heights.

The tripod stepladder of this invention alleviates the abovementioned problems and includes a main frame that has an inverted, substantially U-shaped form. Extending from the top of the inverted U-shaped frame, i.e., from the base of the U, is a tripod leg or support. One or more steps are positioned between the legs or sides of the inverted U-shaped frame. The top step, which is located substantially below the top of the U-shaped frame, carries a platform that is pivotally connected at one end to the step and is adapted to slide along the third leg of the ladder while engaged therewith at the other end. Thus, the platform may be pivoted from a substantially vertical to a substantially horizontal position as the third leg is swung from the closed or storage position to the use or tripod position of the ladder.

Therefore, it has been the primary objective of this invention to provide a stepladder of the tripod type that is particularly adapted to be used in corners of a room.

It has been another objective of this invention to provide a stepladder of the tripod type having support means extending above the top step or platform so that the user may readily support himself while standing on the platform by either leaning into or holding onto a rest bar.

It has been yet a further objective of this invention to provide a stepladder of the tripod type which has a relatively high degree of stability and balance.

It has been still another objective of this invention to provide a stepladder of the tripod type which may be easily, quickly and efficiently stored, and is particularly adapted to household use.

These and other objects and advantages of the present invention will be more readily apparent from the following detailed description of the drawings which illustrate a preferred embodiment of the invention.

In the drawings:

FIGURE 1 is a perspective view of the stepladder of this invention shown in the tripod or use position.

FIGURE 2 is a perspective view -of the stepladder shown in the closed or storage position.

FIGURE 3 is a view similar to FIGURE 2 showing the third leg partially broken away to depict the underside of the platform structure.

FIGURE 4 is a fragmentary cross sectional view taken along line 4-4 of FIGURE 1.

FIGURE 5 is a fragmentary cross sectional view taken along line 5 5 of FIGURE 4.

FIGURE 6 is a fragmentary cross sectional view taken along line 6 6 of FIGURE 4.

FIGURE 7 is a fragmentary cross sectional view taken along line 7-'-7 of FIGURE l.

In accordance with the principles of this invention, and as best seen from FIGURE 1, the preferred embodiment of the tripod stepladder includes an inverted, substantially U-shaped main frame 10 having outwardly ilaring side posts 11, 12 and a curved base or rest bar 13. Pivotally secured to the center of the rest bar 13 is a third leg 14. The third leg 14, being pivotally disposed with reference to the U-shaped main frame 10, is connected thereto by means of a connector sleeve 18 rotatably mounted on the rest bar 13 of the main frame 10. Disposed intermediate the side posts 11, 12 of the substantially U-shaped frame 10 are a bottom step 16 and a top step 17.

The connector sleeve 18 includes a downwardly projecting, narrowed neck 19, the neck being of a diameter to receive and hold the tubular third leg 14 thereon in a friction lit, a pin 20 also being used to hold the third leg to the connector sleeve. Projecting outwardly and upwardly from the neck 19 of the sleeve 18 is a hook 21. The hook 21 provides means for holding, for example, a bucket or pail 22 in a work position when using the ladder. The main frame 10, third leg 14 and steps 16, 17 are preferably formed from aluminum alloy tubing to permit easy shaping of the main frame as well as to lower manufacturing costs. In addition, the light weight of the tubing makes the stepladder more attractive to the housewife. Of course, the bottom ends of the legs 11, 12 of the U-shaped main frame 10 and third leg 14 may be provided with rubber cups 23 to prevent scratching of the floors when the ladder is being used. Because the third leg 14 is pivoted at the very top of the ladder, i.e., at the rest bar 13, very good stability and balance result in the ladder, thus making it quite safe for use in the home by the housewife.

A platform 24 is pivotally mounted on the top step 17. The platform 24 is provided with a top or standing area 26 and depending sides 27, 28 that are integral with the top and join in an overlapping seam 36 at apex 29 of the triangularly shaped platform, as best seen in FIGURES 3 and 6. Secured to the inside of the overlapping seam 36, by means of rivets 38, is a curved support 37 which is provided to substantially reduce any material weakness which may arise through repeated use. The substantially triangular shaped platform 24 has at its front or apex 29 a slideway or aperture 31 provided for the third leg 14 to extend through in sliding relationship. Each side of the rear 32 of the triangular platform 24 carries a tubular retainer 33 that is integral with the top 26 of the platform 24. The retainers 33 encircle the top step 17 and are fastened to the bottom of the platform 24, as best seen in FIGURE 4, by suitable fastening means, e.g., rivets 25. Thus, the platform 24 is permanently and pivotally secured to the top step 17 of the stepladder. Provided intermediate of the length of the tripod leg 14 is a stop or pin 34 adapted to cooperate with the bottom of the reinforced seam 36 to hold the platform 24 in a horizontal position when the ladder is in the use or tripod position. It will be noted that additional maneuverability for the user is provided by the platform 24 because the platform defines a working or standing area substantially larger than the normal stepladder step.

The sliding relationship of the tripod leg 14 to the slideway 31 at the platform apex 29 forces the tripod leg 14 into the tripod or use position as the platform 24 is pivoted from a substantially vertical or storage position, as seen in FIGURE 2, through an intermediate position, as seen in FIGURE 3, to a substantially horizontal or use position, as seen in FIGURES 1 and 4. As mentioned,

the pin 34 cooperates with the bottom of the reinforced seam 36 formed by the depending sides 27, 28 to prevent the platform from moving to an angle substantially below the horizontal.

Thus, it may be seen that a simple household stepladder has been provided that is constructed from a minimum of parts. The st'epladder may readily be used in corners, thereby permitting the user to stand in a close working relationship with the corner, and not some distance therefrom. In addition, the upper portion of the U-shaped frame permits the user adequate -support by either leaning into the rest bar 13 and side posts 11, 12 of the main frame 10 or by holding onto the rest bar or side posts of the frame with the hand.

Having defined and described the preferred embodiment of my invention, what I desire to claim and protect by Letters Patent is:

A stepladder of the tripod type comprising two side posts,

at least two steps disposed between said side posts,

a rest bar integral with said side posts, said rest bar and said side posts having a substantially inverted U- shaped configuration,

a tripod leg pivotally connected at one end to said rest bar and,

a standing platform disposed susbtantially below said rest bar and pivotally connected to the uppermost step at one end,

said platform including rigid structure means defining an aperture at the other end of said platform, said aperture positioned so that said tripod leg passes therethrough,

and a stop associated with said third leg for maintaining said platform substantially horizontal when said ladder is in a tripod position,

whereby said platform pivots upwardly about said uppermost step as said tripod leg is pivoted to a storage position subsantially parallel to said side posts, and said platform pivots downwardly about said uppermost step to a working position as said tripod leg is pivoted to the tripod position.

References Cited UNITED STATES PATENTS 855,872 6/1907 Bedford 297-58 2,478,592 8/1949 Nyberg 182-125 2,649,140 8/ 1953 Housel 297-57 FOREIGN PATENTS 2,801,304 4/ 1952 Switzerland.

REINALDO P. MACHADO, Primary Examiner.

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