US1783616A

US1783616A - Stepladder

Info

Publication number: US1783616A
Application number: US333792A
Authority: US
Inventors: Henry C Hachmuth
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-01-21
Filing date: 1929-01-21
Publication date: 1930-12-02
Anticipated expiration: 1947-12-02

Description

Dec. 2, 1930. H. c. HACHMUTH STEPLADDER Filed Jan 21, 1929 'Ilz Yeh Zor.

Patented Dec. 2, 1930 :[-IIEIVEJSZ C. I-IACI-IMUTH, F COMSTOCK PARK, MICHIGAN STEPLADDER Application filed. January 21, 1929. Serial No. 333,792.

This invention relatesto step ladders and its object is to provide a step ladder having legs which will move about relative to each other and readily accommodate their posi- .5 tions to an uneven surface on which the ladder is supported and will support the ladder on such an uneven surface rigidly and without fear of tipping. This ladder is primarily intended for use in orchards and other places lo out of doors, on hillsides or rough uneven ground but it is equally adaptable for use in other places and in any place where a step ladder of any kind may be used.

The invention embodies various new and useful features of construction and arrangement as hereinafter more fully described and particularly pointed out in the claims, reference being had to the accompanying drawing, in which,

Fig. l is a perspective view of a step ladder embodying this invention and showing the essential features of construction.

Fig. 2 is a front view of the upper end of the step ladder.

F ig. S is a side view of the same, and

F ig. 4 is an enlarged rear View of the swinging rear leg supporting structure removed from the ladder and with the lower portion broken away.

Like numbers refer to like parts inall figures. Y

rlhe ladder embodying this invention has conventional front leg and step construction 1 to the upper end of which is attached the usual broad top step or ladder top 2. The two front legs are spaced apart and the steps of the ladder extend between them in conventional forin and the top 2 is preferably attached to the upper ends of the front legs 40 by means of angle plates 3 secured by suitable fastening means such as bolts or

rivets

12 and 13.

A supporting plate 6 is located closely beneath the ladder top 2 near the rearV edge thereof and is pivotally connected by bolts or other suitable pivot means 14 to the angle plates 3 so that it will swing on a horizontal axis. This supporting plate 6 carries the adjustable rear legs 4 of the ladder. A vertical 59 shaft l1 extends through the central portion of the supporting plate 6 and is rotatable in the plate on a substantially vertical axis at all times perpendicular to the axis of the pivots 14 of the plates 6. The plate 6 is preferably formed of sheet metal and has flanges turned at right angles to it at its upper and lower edges an d at its ends and the end flanges serve as means through which thev pivots 14 extend and the upper and lower fianges provide portions through which the shaft 1l ex- 60 tends. Other structures maybe utilized in this respect and the sheet metal construction shown is not important to the invention.

`The lower portion of the shaft 11 below the supporting'plate 6 is provided with opposite- 65 ly extending ears 8 and the two rear legs 4 are respectively pivotally connected at their upper ends to each of said ears 8. Below the ears 8 and centrally located with the axis of the shaft 11, a stud 17 extends at right angles 70 to the axis `ofsaid shaft and a lever 10, forming a part ofan equalizing device, is pivoted mid-way between its ends on the stud 17. Each end of the lever 10 has a link 9 pivotally attached to it and the opposite end of each link 9 -is pivot-ally connected by a bolt or stud Y 18 to a respective leg 4 at a point spaced below its pivotal connection with an ear 8. In the specific construction shown a square elongated block 5 is provided with an axial open- 8o ing toreceive the-lower `end of the shaft 11, whichshaft is held in place in the block 5 by the stud 17 which extends through it and the upper end of the block serves as a shoulder to engage the lower surface of the supporting plate 6j The ears 8 are in the form of plates 'applied to opposite sides of the block 6 by fastening means 15 and the upper ends of thelegs 4 lie, and are pivoted between the two plates 8. This specific construction, however, is not essential and any structure providing the Vshaft 11 with a shoulder to engage the lower surface of the plate 6 and having ears to which the upper ends of the legs 4 may be pivotally attached and a stud 17 will properly function. The upper end ofV the vshaft 11 is provided with 'a retaining means such as a cotter pin 1() extending through it .to retain it in place in the supporting plateA 6.

This structure permits the lower ends of the rear legs l to be spread apart at will and the leveling` device comprising the lever l0 and the links 9 causes them to move uniformly with respect to the axis of the shaft 1l. The shaft l1 will pivotin the supporting plate G on an axis perpendicular to the pivots 14. and the supporting plate 6 will swing relative to the front legs of the ladder and its top on said pivots l-l. By this arrangement the user may place the front legs of the ladder upon the ground or supporting surface in the desired location irrespective of the unevenness of the surface and tip the ladder backward to the desired angle and then spread the rear legs 4l and turn them about the axis of the shaft 11 and swing them about the pivots 14 until they automatically lind a firm engagement with the ground and this universal pivoting and swinging and mounting of the rear legs permits them to firmly engage the ground regardless of its uneven surface.

claim:

l. A step ladder comprising a front leg structure, a rear leg structure, a supporting plate pivotally connected to the upper end of the front leg structure to swing on a horizontal axis and means for mounting the rear leg struct-ure on said supporting plate to turn on an axis substantially perpendicular to the support on which the leg structures of the step ladder rest.

Q *A step ladder comprising a front leg structure, a supporting plate pivoted on a horizontal axis to the upper end of said front leg structure, a mounting bracket pivotally connected to said supporting plate on an axis perpendicular to said horizontal axis of said supporting plate, two rear legs pivotally connected at their upper ends to said mounting bracket and an evener associated with said mounting bracket and said rear legs causing the legs to swing uniformly relative to the perllendicular axis of the mounting bracket.

3. A step ladder comprising a front leg structure, a supporting plate pivoted on a horizontal axis to the upper end of said front leg structure, a mounting bracket pivotally mounted on said supporting plate on an axis perpendicular to the horizontal axisA of the plate, two rear legs pivotally connected at their upper ends to said mounting bracket7 a lever pivotally connected between its ends to said mounting bracket, and a link pivotally connected to each end of said lever, each link being also pivotally connected to a respective rear leg.

l. A step ladder comprising a front leg structure, a rear leg structure, a supporting plate movably connected to the upper end of the front leg structure and means for mounting the rear leg structure on said supporting plate to turn about an axis substantially perpendicular to the support on which the leg structures of the step ladder rest.

5. A step ladder comprising a front leg structure7 a supporting plate pivoted on a horizontal axis to the upper end of said front leg struct-ure, means pivotallv connected to said supporting plate on an axis perpendicular to said horizontal axis of said supporting plate, two rear legs pivotally connected at their upper ends to said means and an evener associated with said means and said rear legs for causing the legs to swing uniformly relative to the perpendicular axis of the said means.

HENRY C. HACHMUTH.