Improvements in Adjustable Trestles and Ladders applicable for Lifting Purposes.
Year: 1894

page_text: Date of Application, 12th Oct., 1894--Accepted, 22nd Dec., 1894
Improvements in Adjustable Trestles and Ladders applicable for
Lifting Purposes.
We, JOHANN STEINFELD, Gentleman, and THEODOR BECKER, Engineer, both
of Mülheim on the Rhine, in the Province of Rhineland and Kingdom of Prussia,
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 invention hereafter described and explained by drawings relates to a trestle
which by means of mechanical devices may be adjusted and secured at any height,
and which, since it occupies very little room when laid together, is easily transported
from one place to another. The trestle may also be supplied with wheels, which
can be turned up when the trestle is in use, in order to prevent it slipping.
This trestle may be employed in a variety of ways, thus for instance in the
house as a window- and step-ladder, as a ladder for painters and decorators and
also for building purposes, several of these trestles being placed alongside of each
other in front of the building and being connected suitably by a number of beams
or planks. On the building becoming higher, according to the height and size of
the trestles at disposal, either the whole scaffolding with the upper layer of planks
may be gradually raised, or a fresh number of trestles may be placed on the lower
layer of planks and these trestles covered with another layer of planks and so on.
In order to be able conveniently to raise the building materials such as stones,
mortar, or, in the case of a bridge, such as girders etc. to the level of the higher
situated working places a single trestle may be arranged as a lift which is moved
along the front of the building and after being laid together receives the building
inaterial on a podium and takes it to the desired height by the rising of the
trestle.
Such trestles are very advantageously employed where heavy blocks of stone
bave to be raised, as it is possible to raise or lower the whole scaffold exactly to
such a level that the block may be pushed on horizontally to its bed.
'
As will be seen from the drawing the trestle consists of two side-beams arranged
parallel to each other and formed of jointed rails a a. These beams, as will be seen
from Figs. 2 or 3, are connected with each other by cross-stays b of wood, or, when
the scaffolds are heavy, of metal such as gas-pipes, in such a manner that these
cross-stays form at the same time the hinge-bolts for the different rails.
According as the scaffolding is to serve one of the above-mentioned purposes,
the rails a a are either made of wood or of flat or [ iron etc. and put together in
such a manner that each side-beam is like a lattice-work which can be pushed
upwards (Fig. 1 dotted).
On the cross-stays between the ends of the rails lying near each other on one
side of them, are the pulleys cover which runs a rope or chain d. The latter is
attached above or below to the furthest cross-stay, passes successively over all
the pulleys of one side-beam and is wound up at the other end on a shaft e which is
in connection with a corresponding windlass f.
In the drawing in Figs. 1 to 3 that form of scaffolding is shown in which the
windlass is placed on the podium and the rope fastened to the lowest cross-stay.
By simply turning the crank of the windlass which is provided with a click and
ratchet-wheel, by which means the ropes d draw the opposite cross-stays towards
each other, the workman standing on the podium is able to raise himself by means

page_text: of the scaffolding to any desired height and keep the scaffolding at that height by
means of the click and ratchet-wheel. By reversing the windlass and at the same
time using a break-mechanism attached to it the scaffolding may be again folded
together.
If the scaffolding is to be employed for raising heavy loads, the windlass may be
fixed at the bottom of it and be provided with two cranks, so that it can be worked
by two men, thus greatly facilitating the work.
In Fig. 4 a form of the scaffolding intended for fire-men is represented, being in
the shape of a ladder.
In this case the ladder runs on rails and is placed in a small carriage h. The
ladder is either kept continuously in this carriage or is taken out of it before being
used. Hooks or rope-ladders may be attached at different places to the sides of the
trestle so that the inhabitants can escape very quickly and easily from a burning
house. In order to obtain a greater amount of stability in the scaffolds which
have been described, especially when they have been stretched out to a con-
siderable height, it is of advantage to arrange the beams so that they incline
towards each other. The beams themselves should taper towards the top i.e. the
cross-stays as well as the different lattice-rails should be made gradually shorter
towards the top.
Instead of the windlass for raising and lowering the scaffolding, a screw-spindle
may be also used, which is attached to it and worked in a suitable manner.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
1. Trestle, distinguished by the arrangement of two side-beams composed of two
or more lattices formed of jointed rails a a, and capable of sliding together and
connected by cross-stays, in connection with a rope or band (chain and the like)
worked by a windlass and running over pulleys and causing all the lattices to be
drawn together, thereby making a rapid expansion and contraction of the trestle
possible.
2. The connection of the arrangement distinguished under 1, with a carriage as
a ladder for fire-brigades.
Dated this Tenth day of September 1894.
For JOHANN STEINFELD and
THEODOR BECKER,
Bernhard Brockhues.