Improvements applicable to Extension Ladders.
Year: 1891

page_text: Date of Application, 3rd Oct., 1891
Complete Specification Left, 10th June, 1892-Accepted, 17th Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements applicable to Extension Ladders.
I, CANCIANO CANCIANI, of Udine, Italy, Engineer, do hereby declare the nature
of the said invention to be as follows:-
The object of this invention, which relates to improvements applicable to extension
ladders, is to maintain the rigidity of such ladders not only when the same are fully
extended but also when they are in a horizontal position or when being raised or
lowered. The improved system comprises rigid fixed diagonal braces and flexible
movable parallel chain-braces or stays arranged as hereinafter described.
A main spindle is arranged under the opposite sides of the first section of the
ladder (that which is secured to the car), and is fitted with two drums arranged
between the sides of the ladder and close thereto, and is operated by a toothed
wheel and double cranks placed at either side of the ladder.
On each drum four metal chains are wound up in contrary directions. When
the spindle is turned in the one direction, the chains are wound up so as to cause
the second section of the ladder to extend and at the same time move all the other
sections of which the ladder consists.
The said chains pass from the drums over pulleys arranged at the upper end
of the first section of the ladder, and are attached to the lower end of the second
section near its edge.
Other chains are secured to the upper end of the first section of the ladder and
to the spindles of the said pulleys and pass over other pulleys arranged at the other
end of the second section of the ladder, and these chains are attached to the lower
end of the third section near its edge, and so on for the remaining sections of the
ladder. Thus, the sliding of the second section will at the same time effect the
sliding of any number of other sections in like proportion.
The various chains not only serve to extend the ladder but also as counter stays.
The diagonally arranged rigid stays are formed of iron rods and move only with
those sections of the ladder to which they are attached. The flexible movable
parallel stays are formed of lengths of chain with steel rings.
The first lower portions of the chains and lengths of chain firstly and lastly
referred to, are, as aforesaid, wound upon drums on the main spindle in opposite
directions, so that in winding up the unfolding chains causing the several sections
of the ladder to slide one upon the other, a similar unrolling of the said lengths
of the chain (or movable stays) is obtained, likewise permitting the second section to
unfold whilst maintaining it rigid and inflexible.
The other sections of the ladder are also fitted with similar stays whereof one
end is fixed at the upper end of that section of the ladder which is immediately
underneath, and after running over the said pulleys placed at the end of each
section of the ladder it is fixed at the other end to the end of the rigid oblique stay
next above it.
It follows from this arrangement, that in expanding or shortening each section
of the ladder by a given portion, the stays lengthen or shorten in the same measure
thus constantly maintaining the rigidity of the entire system.
The said spindle serves also as the fulcrum for altering the elevation of the
ladder, which works as a lever, by means of a rope actuated by a winch handle.
The ladder, when not in use, is lowered and arranged horizontally on the car;
to put it into use, the ladder is raised by the winch handle and placed almost
upright, then the aforesaid cranks are turned to obtain the partial or total extension
of the ladder as may be required. The change in elevation and variation in length

page_text: may be effected at the same time, or the variation in length may be effected while
the ladder is horizontal.
.
The ladder may rest on a car supported by wheels, the car being in proportion
to the weight and dimensions of the ladder, the extension whereof may be effected
by one or two persons in'a short period of time.
The ladders may be made of any size and length, subject only to safety and the
necessary speed in working.
Dated this 19th day of September 1891.
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements applicable to Extension Ladders.
1, CANCIANO CANCIANI, of Udine, Italy, Engineer, do hereby declare the nature
of the said invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
This invention relates to improvements applicable to extension ladders, the main
object of the invention heing by a system of automatic braces or stays to maintain
the rigidity of such ladders, not only when the same are fully extended, but also
when they are in a horizontal position or are being raised or lowered.
The improved system comprises rigid fixed diagonal braces and flexible movable
parallel chain braces or stays arranged as hereinafter described with reference to
the accompanying drawings.
On the drawings ;→
Fig. 1, represents an extension ladder adapted according to the present improve-
ments, representing the same in side elevation and closed up.
Fig. 2, represents a like view of the ladder when extended.
Fig. 3, represents a sectional elevation, transversely of Fig. 1, representing the
positions of the sections of the ladder.
A main spindle A, is arranged under the opposite sides of the first section of
the ladder (that which is secured to the car) and is fitted with two drums arranged
between the sides of the ladder and close thereto, and is operated by toothed wheels
and a double winch-handle B, which can be operated from each side of the
ladder.
On each drum two pairs of chains, C, O, are wound up in contrary directions,
so that when the spindle is turned in the one direction (say from right to left) the
chains C, are wound up so as to cause the second section of the ladder to extend
and at the same time to move all the other sections of which the ladder consists.
The chains C, pass from the said drums on the spindie A, over pulley's H,
arranged at the upper end of the first section of the ladder, and are attached to the
lower end of the second section near its edge.'
1.F
Other chains C¹, are secured to the upper end of the first section of the ladder
and to the spindles of the pulleys H, and pass over other pulleys H', 'arranged
at the other end of the second section of the ladder, and these chains C₁, are
attached to the lower end of the third section of the ladder near its edge, and bo
on for the remaining sections of the ladder. Thus, the sliding of the second
section will at the same time effect the sliding of any number of other sections in
like proportion.
..
The various chains C, C³, C³, C³, C², C³, serve not only to extend the ladder,
but also as counter-stays.
The diagonally arranged rigid stays are formed of iron rods T, and move only

page_text: The first lower portions of the chains or stays O, are wound upon the respective
drums on the main spindle A, in opposite directions to the chains C, so that in
winding up the unfolding chains, causing the several sections of the ladder to slide
cne upon the other, a similar unrolling of the chains O, (or movable stays) is
obtained, likewise permitting the second section to unfold whilst maintaining it
rigid and inflexible.
The other sections of the ladder are also fitted with similar stays, whereof one
end is secured at the upper end of that section of the ladder which is next underneath,
and after running over pulleys c, (placed at the end of each section of the ladder)
it is secured at the other end to the end of the rigid oblique stay next above it.
It follows from this arrangement, that in extending or shortening each section of
the ladder by a given portion, the stays lengthen or shorten in the same measure,
thus constantly maintaining the rigidity of the entire system.
The spindle A, serves also as the fulcrum for altering the elevation of the ladder
(which works as a lever) by means of a rope or cable F, actuated by a winch-
handle M.
The ladder, when not in use, is lowered and arranged horizontally on the car,
vide Fig. 1. To put it into use, the ladder is raised by the winch-handle M, and
placed almost upright; then the winch-handles B, are turned to obtain the partial
or total extension of the ladder as may be required, and which may be effected by
one or two persons in a very short period of time.
The change in elevation and variation in length may be effected at the same
time, or the variation in length may be effected while the ladder is horizontal.
The ladder may be made of any size and length subject only to safety and
necessary speed in working, and may rest on a car supported by wheels as
represented; the car being made in proportion to the weight and dimensions of
the ladder.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is:-
1. The application to extension ladders of the hereinbefore described system of
automatic braces or stays operating to prevent flexure thereof.
2. The application to extension ladders of the herein before described system of
chains used both for obtaining the extension of the sections of the ladder and acting
as counter-stays maintaining its stability.
Dated
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.