US3032140A - Ladder attachments - Google Patents

Description

May 1, 1962 H. HUNT LADDER ATTACHMENTS 2 Sheets-Sheet 1 Filed Nov. 4, 1960 INVENTOR. HOMER HUNT May 1, 1962 H. HUNT LADDER ATTACHMENTS 2 Sheets-Sheet 2 Filed Nov. 4, 1960 INVENTOR. HOMER HUNT Fatented May 1, 1962 3,032,140 LADDER ATTACHMENTS Homer Hunt, 779 Connecticut Blvd, East Hartford, Conn. Filed Nov. 4, 1960, Ser. No. 67,372 1 Claim. (Cl. 182-201) This invention relates to improvements in ladder attachments capable of use in connection with ladders of various styles and dimensions upon stairs or other inclined or uneven surfaces and has special references to devices for the stated purposes of the types shown in Letters Patent No. 1,393,536, granted to me October 11, 1921, and Letters Patent No. 1,462,505, granted to me July 24, 1923. The object of the present invention is to increase the etficiency of the attachment, and also to simplify its construction so as to effect an economy in manufacture. The invention is illustrated in the accompanying drawings and will be hereinafter fully set forth.

In the drawings-- FIGURE 1 is a fragmentary perspective view of a step ladder equipped with my improved extension attachment on one leg, as used when in place upon a flight of stairs with top of ladder resting against the wall. This view shows the extension leg attached in a straight line with ladder leg;

FIG. 2 is a fragmentary perspective view of step ladder equipped with my improved ladder attachment on both ladder leg and prop, and attached at an angle thereto;

FIG. 3 is a fragmentary front elevation of a straight ladder having the attachment applied thereto;

FIG. 4 is a view of attachment on a fragmentary extension leg with the clip plates adjusted at an angle thereto;

FIG. 5 is a perspective view of the attachment removed;

FIG. 6 is a sectional View along the line 66 of FIG. 1;

FIG. 7 is a rear view of a clip plate;

The step ladder indicated at 1 in FIGS. 1 and 2, may be of the usual construction embodying legs 2 and a prop 3. In carrying out my invention, I employ two pairs of integrally formed clip plates each having an elongated arm portion 4 and a pair of lugs or ears 5 at the center thereof extending normally to the arm portion and oppositely of each other, as shown most clearly in FIG. 4. These clip plates are provided on their opposed faces with projections or teeth 6 which extend over substantially the entire arm portion 4 and ears 5 and which teeth are adapted to engage in the material of the leg 2 or the prop 3 of the step ladder, or the extension leg 10. The object of the ears 5 is to supply additional clamping surface to the clip plates and increase stability of their setting, especially when they are adjusted at an angle on narrow legs or props as most clearly shown in FIG. 4, and on the prop in FIG. 2. These clip plates have openings 7 formed through the ends of the arm portions, through which bolts 8 are inserted to connect said clip plates, as shown and will be readily understood. Fitted upon the threaded ends of said bolts 8 and adapted to be turned home against the clip plates are winged nuts 9 whereby the back clip plates may be secured against the ladder leg 2 or prop 3, and the extension leg 10 securely clamped between the ladder leg or prop and the opposing clip plates.

The two pairs of clip plates are connected by metal straps 11 placed one on the front and one on the back of the attachment. These straps 11 are attached to the center portion of the clip plates by the use of rivets 12 7 which are left sufiiciently free to allow the clip plates to oscillate to any desired angle to the ladder leg or prop.

The purpose of this variation of position is most clearly shown in FIG. 1 where the attachment being placed on a wide ladder leg is attached at a right angle thereto, while, in FIG. 4, where the attachment is on a narrow leg, the attachment is adjusted at an angle which still allows the full length of the clip plates 4 including the ears 5 to contact the ladder leg and/or the extension ieg, thus giving a maximum of security and stability not obtained otherwise. As clearly shown in FIG. 4 and FIG. 5 the straps 11 hold the attachment in whatever position it may be adjusted.

From the foregoing description, taken in connection with the accompanying drawings, it will be seen that my improved attachment is an exceedingly simple device whereby an extension leg may be quickly and firmly secured to a ladder to project beyond the lower end thereof and engage the surface upon which the ladder is to be set up. The device may be readily adjusted longitudinally of the ladder leg or prop before the nuts 9 are turned home and, after being set in the adjusted position, may be secured in that position quickly and easily by merely turning home the said nuts 9. The attachment is of such dimensions that it will fit ladder legs of various widths and thicknesses. Also, there is sufficient width to allow the extension leg to be arranged parallel with the longitudinal lines of the ladder leg FIG. 1 or, be attached at an angle thereto, as in FIG. 2. The projections of teeth 6 upon the clip plates 4 will embed themselves in the ladder leg and extension leg so that, after the clamping nuts have been turned home, slipping of the device upon the ladder leg or extension leg will be effectually prevented. My improved device may be produced at a lower cost and may be very readily attached to ladders of various sizes and kinds without the use of skilled labor.

Having thus described the invention, what is claimed as new is:

An attachment for securing an extension leg and the like to the leg of a ladder comprising two spaced pairs of clip plates adapted to extend generally transversely of and bear upon opposite sides of an associated assembly of a ladder leg and extension leg to be clamped together thereby, each of said clip plates being integrally formed with an elongate arm portion and a pair of ears at the center portion of said arm portion extending normally thereto and oppositely of each other, said pairs of clip plates having opposed gripping surfaces over the ears and substantially the entire arm portion; means connecting the ends of the arm portions of each pair of clip plates for securely clamping said clip plates to the opposite sides of an associated assembly of a ladder leg and extension leg; and straps on opposite sides of said attachment connecting said pairs of clip plates, said straps being pivotally connected to the clip plates adjacent the center portions of the arm portions to permit angular adjustment thereof relative to the longitudinal dimension of an associated ladder.

References Cited in the file of this patent UNITED STATES PATENTS 437,935 OBrien Oct. 7, 1890 638,987 Porten Dec. 12, 1899 656,298 OBrien Aug. 21, 1900 1,243,532 Krieger Oct. 16, 1917 1,462,505 Hunt July 24, 1923 2,320,144 Johnson May 25, 1943 FOREIGN PATENTS 49,919 Sweden July 14, 1920 894,499 France Mar. 13, 1944 613,306 Great Britain Nov. 24, 1948

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