US2562564A - Ladder tread - Google Patents

Description

J. L. MCGLOTHLEN July 31, 1951 LADDER TREAD 2 Sheets-Sheet 1 Filed March 12, 1946 ToRNEYs July 31, i951 J. L. MCGLOTHLENA LADDER TREAD 2 Sheets-Sheet 2 Filed March l2, 1946 i Il 'I Il 1| Il ll ll 'I :l h

INVENTOR VNm (John @MCG/(nemen RNEYS Patented July 31, u*1951 UNITED STATES PATENT OFFICE LADDER TREAD John L. McGlothlen, Pittsburgh, Pa..

Application March 12, 1946, Serial No. 653,855

1 claim. 1

This invention relates to ladders and, in particular, to step ladders although certain features are applicable to ladders generally.

Step ladders are frequently used for work on walls, i. e., painting, washing and the like. Step ladders of conventional construction, however, having relatively narrow treads, do not afford secure footing for a person standing thereon when he turns to one side as is necessary when working on a wall with the ladder positioned adjacent thereto. I have invented a novel form of step ladder whereby a person using it for wall work has equally good footing whether turning to the side or facing straight ahead of the ladder. In a preferred embodiment, I provide a ladder having spaced risers with treads extending therebetween in vertically spaced relation, the treads being .bowed or offset inwardly in their intermediate portions so as to project laterally beyond the ends. Preferably the treads are of curved conformation and thus afford ample area for safe footing whether the user turns toward one side of the ladder or stands facing forward. The outer edge of the treads is cut out or curved inwardly so that the treads have substantially the same width at all points. This provides knee room and enables the user to brace himself firmly against the tread above that on which he is standing.

A complete understanding of the invention and the various additional features of novelty and advantages which `characterize it may be gained from the following detailed description and explanation which refer to the accompanying drawings illustrating a preferred embodiment. In the drawings,

Figure 1 is a front elevation;

Figure 2 is a side elevation;

Figure 3 is a partial section taken along the plane of line III- III of Figure 2;

Figure 4 is a partial section taken along the plane of line IV-IV of Figure 3;

Figure 5 is a plan Aview ofia deck plate removably disposable on any one of the treads;

Figure 6 is a transverse" section therethrough taken along the plane of line VI-VI of Figure 5;

Figure 7 is a front elevation of a modified form of my invention;

Figure 8 is a side elevation of the ladder shown in Figure '7 Figure 9 is a horizontal section taken along the plane of line IX-IX of Figure 8;

Figure 10 is a vertical section taken along the plane of line X--X of Figure 9;

Figure 11 is a rear elevation of a receptacle attachable to the step ladder of Figures 1 through 6; and

Figure 12 is an end elevation thereof.

Referring now in detail to the drawings and, for the present, to Figures 1 through 4, the ladder of my invention comprises risers I0 and II having treads I2 extending therebetween and a top plate I3 rigidly secured to the upper ends thereof. Bracing legs I4 are pivoted to the top plate I3 at I5. Each riser comprises a pair of spaced angle bars I6 and I'I having short lengths of angle bars I8 extending therebetween and secured thereto. The treads I2 rest on the angle bars I8. A diagonal brace I9 extends between the bars I6 and Il' and a short length of angle bar 20 connects the latter a shortdistance above their lower ends. Angle clips 2I are secured to the lower ends of the bars I6 and Il and the bracing legs I4 composed of similar bars, to provide a box end adapted to receive shoes 22 of rubber or vother suitable material.

The risers III and II'and-the Abracing legs I4 are parallel for the greater portion of their length, being bent outwardly adjacent their lower ends as at 23 and 24 for greater stability. The bracing legs have .diagonal cross braces 25 extending therebetween and are held in proper relation to the risers by pivoted spreader links 26 of known construction. A bucket support 21 is pivoted to the legs I4 in the usual manner and has projecting arms engaging under the top tread I2.

The treads I2 are all videntical and, as best shown in Figure 3, have -their midportions 28 bowing inwardly or offset laterally beyond the end portions 29 which rest on the angle bars I8. A bracing strap I2a is secured to the inner edge of each tread and to the outer edge of the top I3, centrally thereof. The outer edge of each tread and the top I3 has a cut-out 30 so that the width is substantially theY same at all points. In the preferred form, the treads are curved inwardly of the ladder at their midportions beyond the extreme outer ends but the shape of the treads in plan may be defined by broken lines instead of smooth curves as illustrated.- In either case, the treads will afford more secure footing for the user when turning toward one side of the ladder, i. e., will permit him to turnA his feet to the side instead of having to twist hisV body; or attempt to balance himself with the relatively narrow footing available on conventional ladder treads when the feet are disposed at an angle thereto.

The various parts of the ladder are preferably made of light metal such as aluminum, magnesium or the like. The treads I2 may conveniently be formed of sheet metal stampings vand have a downturned flange 3| extending therearound. The treads also preferably have ribs 3 32 pressed therein to increase their rigidity and bosses 33 pressed upwardly to give improved traction and avoid slippage.

A deck plate 34 shown in Figures 5 and 6 is removably disposable on any one of the treads l2 as indicated in chain lines in Figure 4. The plate has downturned anges 35 and 36, the flange 36 having .its bottom edge turned under to engage under thel outer edge of the tread. The 'deck plate, when in position on a tread, provides an enlarged area for supporting miscellaneous objects such as a bucket, tools or the like, and bridges the cut-out 30 in the outer edge ofthe tread. A

The angle bars I6 and I1 of one or both the risers ID and Il are provided with projecting rivets 31 whereby a receptacle 38 may be detachably mounted on the ladder. The receptacle is simply a box open at the top and may conveniently be of sheet :metal construction, the back Wall thereof having key-hole slots 39 adapted to cooperate with the rivets -31.

Figures 7 through V10 show a straight ladder having certain features of my invention incorporated therein. The straight ladder, as shown, comprises .risers 40 and 4I, each composed of angle bars 42 and 43. Treads 44 extend between the risers in vertically spaced relation. These treads are generally similar to the treads l2 except that their inner edges are straight, the outer edge being cut out as at 45, in somewhat the .same .manner as the treads i2. The treads are pivoted to the angle bars. Through pins 43 extends between the angle .bars 42 of the two risers and through the downturned side flanges of the treads. Short pins 41 extend through the angle bars v43 and the tread ilanges. Spacer bars 48 extend between corresponding angle bars of the risers adjacent the upper and lower ends thereof.

Short lengths of angle bar 45 are secured to the lower ends of the angle bars 42 and 43 to afford a box section foot and a U-shaped strap 50 is fitted over this foot. Angle bars are pivoted to the extreme lower ends of the angle bars 42 and 43 of each riser and 'angle bars 52 are pivoted to the upper ends thereof. Downwardly extending pads 53 are secured to the bars 5| and laterally projecting pads 54 to the bars 52. The pads 53 and 54, of course, are adapted to engage the floor and wall, respectively, or other surfaces on whichthe ladder may be used, as shown in Figure 8, and are preferably composed of rubber or similar material having a high coefficient of friction and of such vresilience as to avoid marring finished floors and Walls.

The joints between the various members of the straight ladder may be rigid or may permit relative angular movement against frictional resistance, to enable the treads to be maintained horizontal for various angular positions of the ladder as a whole. In other words, the straight ladder is of hinged construction throughout and may thus be folded down so that the angle bars 42 and 43 approach each other quite closely, for storage or transport.

risers afford toe room at the extreme ends of the treads. The cut out in the outer edge of the "treads, furthermore, permits the user to brace his legs on the tread above that on which he is standing. The utility of the ladder and the safety of the user are thus substantially increased.

While the ladders illustrated have been designed particularly for metal construction, it will be understood that some or all the various parts may be made of Wood or other material.

Although I have illustrated and described but a preferred embodiment and a modification of the invention, .it will be recognized that changes in the details of construction may be made without departing from the spirit of the invention or the scope of the appended claim.

I claim:

A tread for stepladders having a generally flat body portion, straight ends parallel to each other for attachment of the tread to the ladder and front and back edges longer than the ends, the iront edge of the tread extending from each end towards the opposite end to provide a footage area adjacent the iront corners of the tread, the front edge then extending from front to back whereby its central portion is oiset towards the rear edge, the back edge being offset from front to back whereby the tread has substantially the same depth from edge to edge.

JOHN L. MCGLOTHLEN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 34,314 Monson Feb. 4, 1862 106,645 Wright Aug. 23, 1870 372,424 McCollum et al. Nov. l, 1887 372,967 Comins Nov. 8, 1887 421,843 rleal Feb. 18, 1890 666,099 Kepler Jan. 15, 1'901 857,453 Fetta June 18, 1907 1,780,263 Kettmann et al. Nov. 4, 1930 2,103,603 Voigt Dec. 28, 1937 2,230,015 Rich Jan. 28, 1941 y2,304,587 'Morando Dec. 8, 1942 2,368,081 Marsh Jan. 23, 1945 2,527,834 McGlothlen Oct. 31, 1950 FOREIGN PATENTS Number Country Date 380.436 France Oct. 7, 1907

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