An Improved Sliding Double Step-ladder.
Year: 1891

page_text: Date of Application, 15th Sept., 1891
Complete Specification Left, 15th June, 1892-Accepted, 10th Sept., 1892
PROVISIONAL SPECIFICATION.
An Improved Sliding Double Step-ladder.
I, MARTHA BITHORN of 48, Fennstrasse, Berlin, Germany, Gentlewoman do
hereby declare the nature of this invention to be as follows :-
The object of this invention is to construct a step-ladder that can be elongated
or shortened at will.
According to this invention I construct of suitable size four single step-ladders
forming 2 pairs, each pair being of equal length, the top part of each pair I connect
with joints secured by L formed staples fixed to side pieces of steps, the said joints
are sufficiently long with one end bent at right angles so that they may grip the
opposite tread or step when required to lengthen the ladder by the second pair
being added to the first as hereafter described. The upper pair slides inside the
lower and is kept in position by two pieces of iron (one on each side) fitted to side
pieces of upper pair and working in a groove formed in the outer edges of side
pieces of lower pair, to prevent the lower part of steps slipping outwards on the
floor, light tension rods are provided. This invention can be used as one or two
double ladders, or one double and two single ladders, and when not in use, can be
put away in a small space.
Dated this 15th day of September 1891.
BROWNE & Co.,
9, Warwick Court, Gray's Inn, Agents to Applicant.
COMPLETE SPECIFICATION.
An Improved Sliding Double Step-ladder.
I, Martha BitHORN of 48 Fennstrasse, Berlin, Germany Gentlewoman, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
The object of this invention is to construct a step ladder that can be elongated
or shortened at will.
According to this invention I construct of suitable size four single step-ladders
forming 2 pairs, each pair being of equal length, the top part of each pair I
connect with joints secured by formed staples fixed to side pieces of steps, the
said joints are sufficiently long with one end bent at right angles so that they may
grip the opposite tread or step when required to lengthen the ladder by the second
pair being added to the first as hereafter described. The upper pair slides inside
the lower and is kept in position by two pieces of iron (one on each side) fitted
to side pieces of upper pair and working in a groove formed in the outer edges of
side pieces of lower pair, to prevent the lower part of steps slipping outwards on
the floor light tension rods are provided. This invention can be used as one or two
double ladders, or one double and two single ladders, and when not in use, can be
put away in a small space.
And in order that my said invention may be better understood I will now
describe the same with reference to the accompanying sheets of drawings in which,
Figs. 1, 2, 3 and 4 are side and front elevations of a ladder having two parts.
Figs. 5 and 6 sections of such ladder.
Figs. 7 and 8 the support or bracket in front and side view.
Figa. 9. 10. 11 section through a similar ladder with clamps ¹ placed inside.

page_text: Figs. 17. 18. 19, 20 an arrangement for double ladders enabling same to be
used as lean-to ladders.
According to this invention the characteristic feature is that the several parts
of the ladder are connected at their ends by clamps (such as hereinafter described)
which, when the ladder is being extended slide on its sides or cheeks forming
guides.
In double ladders consisting of only two parts (Figs. 1 to 4) the clamps b. are
attached outside alternately on the top and bottom ends of cheeks A, B. so that
when the ladder is being extended the fixed clamp of one cheek slides loosely on
the other cheek (Figs. 5 and 6). In order that with ladders of two or more parts
(Figs. 1 and 2), the parts connected by a hinge may lay lengthwise upon one
another, a groove g. (Fig. 10) is provided on the inner side along which the
guiding clamp. travels. For guiding the clamps a (provided inside or out)
Figs. 10 and 11, or k. (Fig. 5) recesses are provided on the cheeks as in Figs. 10
and 11 or i. Fig. 5 with which the clamps engage.
It is obvious that the top and bottom clamps may be placed in reversed order
and hinges E. E¹ may be used for transforming double ladders into lean-to
ladders.
Connection is made between the two parts E. E' of the hinge by passing the
bolt e' at the end of hinge E¹ into the slot & (Fig. 18.) of the other hinge part
and handle being then turned downwards from the position shown in dotted lines,
Fig. 19, the bolte can not slip out of the slot e.
b
Finally it must be pointed out that on the double ladders brackets m. are pro-
vided (Figs. 3, 4, 7, 8) which increase the stability of the ladders and which, when
the ladders are put together may be turned inward and thus take up no room.
Fig. 21 shows a double ladder not extended and in Fig. 22 the same extended.
The ladder consists of two inner parts a. a. connected by hinge d. and two outer
portions b. b. which slide upon the former by means of the clamps c. and e. The
clamps are placed alternately on the ends of the cheeks or uprights of the ladders
so that the same may be made to slide from the position Fig. 21 towards one
another and into the position shown in Fig. 22 so that the ladder is lengthened.
The parts a and b. are retained in their relative position by the clamps cand e or
otherwise. If only the parts a. are to be used the outer parts 6 may be shipped off
from those before named in the manner shown in Fig. 21. In order that the
hinges d. may not be in the way of clamps c. when this is to be done the hinges d.
are not mounted on the outside of the cheeks or uprights as in all older forms of
similar ladders but on the inside, see Fig. 23. This allows the guide clamps to be
readily pushed past at the hinge portion as clearly appears from the plan view
Fig. 25. In an older form of such double ladders hook-like guide pieces were used
instead of simple guide clamps fitted into guide grooves in the cheeks or uprights.
The latter however were much weakened by the said grooves and therefore
had to be made heavier. and thicker. The present arrangement obviates this
difficulty.
The guide clamps may be made in the manner shown in Fig. 26 and 27, in these
they consist of two parts c. and c¹ connected by hinge i. These clamps present the
advantage that they may be turned down when the ladders are taken apart and
are not in the way when the several portions of the ladder are used separately.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
Constructing ladders substantially as described and shown in the drawings.