Improvements in Portable Scaffolds for use in Building and similar Operations.
Year: 1889

page_text: Date of Application, 28th Oct., 1889-Accepted, 7th Dec, 1889
[Communicated from abroad by AXEL TEODOR NYGREN, of Stockholm, in the Kingdom
of Sweden, Smith.]
Improvements in Portable Scaffolds for use in Building and
similar Operations.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co. Patent Agents,
Southampton Buildings in the County of Middlesex, 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 :-
This invention relates to scaffolds or hoists for the exterior work on buildings
which may be raised and lowered and moved side ways, so that the workmen by means
of the said scaffold may be able during the work to transport himself from one place
to another on the front or side of the building in proportion as the work proceeds.
The improved scaffold or hoist can therefore be substituted for the stationary
scaffolding heretofore used.
The improved scaffold or hoist is illustrated in the accompanying drawing, the
figures of which are hereinafter referred to.
The said hoist consists substantially, as shown in figure 1, of a hoisting chair A the
bearing ropes of which run on four pulleys B fixed on a kind of sliding carriage,
which by means of two other pulleys c runs upon a rail D. The rail Dextends
along the whole front-side of the building and is supported by brackets or
clamping devices fixed to the building in such a manner that its top is free along
its whole length, so that the platform may be moved laterally as far as the length of
the rail. Those brackets, or clamping devices one set only of which is shown in
the drawing are arranged so as to be fixed upon the roof and clasping the cornice
obtains support against the wall.
The part of the bracket or clamping device for clamping the cornice may be
adjusted to different angles so as to adapt the same to the inclination of the roof. It
consists of two inner levers a a' pivoted to a screw nut a³, and an outer main T
lever through one arm of which a screw E passes. By means of this screw the
levers a and b can be drawn towards or moved away from each other. The main arm
of the T lever extends upwards along the roof and is fixed to the roofing partly
by means of the clamp F screwed fast to the water gutter, and partly by means of the
clamp screwed fast to one of the longitudinal flanges of the roofing. To the end of
the arm of the T lever is fixed a chain H, at the other end of which is another
clamp similar to the clamp F, which is secured to the top flange of the roof. By
means of further chains and clamps other holdfasts may be made on the opposite
inclination of the roof.
The arm of the lever b rests, through the medium of a bent piece G and rod b
against the wall, the said bent piece is therefore covered with some soft material C.
From the rod depends a bent lever d, which, clasping the lower edge of the rail,
supports the same and embraces the joints of the said rail. For facilitating the putting
together the rail is composed in such a manner, that at each end of the same there is
an angular slot so arranged that the rail may be looked upon a pine traversing the
opening of the rail at the joint, after which a key ƒ is introduced into the opening
between the ends of the rail. The parts of the rail cannot then be taken asunder,
until the key has been removed. A bent rod g, the end of which is fixed to the rod 61
may be moved along the said rod which therefore is provided with a number of holes

page_text: having for their purpose to maintain the rail at a suitable distance from the
wall.
The hoisting chair is provided with a purchase, so that it may be moved vertically
and sideways either at the same time or alternately.
With the crank shaft k engage both the shafts by means of bevel gearings. On
each of the said shafts are arranged two rope drums m for the hoisting ropes. Two,
other rope drums and o which are geared to the shafts serve to move the scaffold
or hoist sideways. The rope from the last named rope drums pass over guide
pulleys p and is then fixed at the ends of the rail D. The arrangement of gearing
between the rope drums n and o and the shafts is such, that, when the hoisting chair
is raised or lowered by turning the shaft k, the ropes 7 will be rolled up or unrolled
from the rope drums n and o with just the convenient speed.
If the pinion be disconnected, then the hoisting chair may be moved sideways
by turning the respective rope drums n or o, so as to unroll the ropes q from
one rope drum and to roll it upon another. If both the rope drums n and o be loose
and one of them be connected by means of the pinion and the shaft k be
turned, then the platform will at the same time be moved sideways and raised or
lowered. A couple of ratchet wheels s with the past prevent the platform from
running down, and two bars u, provided in the ends with rollers, may be pushed
against the wall so that the platform does not touch the wall but will nevertheless be
suspended steadily.
In lieu of operating the shaft k by means of the crank it may be provided with a
wheel for that purpose; it may be turned round by means of screw gearing. On
buildings having very rounded corners the rail may be made round to suit. On
gables the said rail must be supported by ropes fixed downwards in bearing arms
similar to the arm d, provided with a bent piece so that the bearing arms stand right
out from the wall and at the top is fixed to beams passed through eyelets in the gable
or placed upon the roof with the ends passing the wall, and fixed in a convenient
manner at the roof.
If the roofing is not of sheet iron the lever & must be fixed in
some other suitable manner, but in most cases there will be so many holdfasts, that
ropes may be employed for it. Further it is evident, that it is not absolutely neces-
sary that the bearing ropes run over pulleys in the sliding carriage running on the
rail and that they are fixed with the both ends at the platform, but on the contrary,
they may by means of hooks or the like be fixed directly at the said carriage which is
therefore provided with corresponding rings or hooks in lieu of pulleys.
If the front side be very short or if there be any obstacle to the use of the
rail D, the platform may be susponded on a couple of brackets. The hinges ("
of the carriage may therefore be disposed as shown Figure 1ª so that the same may be
hooked on the arm d. The platform cannot then be moved sideways but its raising
and lowering can take place as before. Figure 2 shows a modification of the brackets
supporting the rail D. With the view of rendering it more simple, it comprises only
a rod b, lever which are mutually united by means of a bow a. The bow permits
the readjustment of the lever so as to be adapted to the inclination of the roofing.
The rod extending along the roofing is provided with a joint at ' so that the whole
bracket may, by means of the chain H be turned round the joint and placed upon
the roofing. The rail may be inserted when the brackets are thus laying upon the
roofing and the brackets and the rail together with the carriage, into which enter
the ropes for lifting the hoisting chair still on the ground may then be lowered at
the same time after which the hoisting chair is lifted.
Figure 3 shows an arrangement for adjusting the platform horizontally. This is
effected by rolling up the rope separately which after the raising or lowering of the
said platform proves to be somewhat too long. The device effecting this consists of a
pawl c fixed at the end of the platform and engaging into a ratchet wheel d¹ fixed
on the shaft on which the rope drum runs loose. The hook c¹ prevents the rope
drum from turning round owing to the extending of the rope. At the opposite end

page_text: of the rope drum, there is a centre f¹ the exterior of which has the shape of a nut. If
the rope is too long, the roller is turned a little by means of a key passed upon the
centre so as to shorten the said rope. The pawl c being actuated by a spring prevents
the rope drum from turning.
It is evident that the rope drums and o provided with the aforesaid device may
likewise be fixed directly on the shafts . When desired to move the platform side-
ways, the said platform is then turned by the aforesaid key, after which it is locked by
means of some suitable device. However the key should preferably be fixed to the
shaft as a crank so that it may be used as a lever.
In order to prevent the platform from swinging to and fro along the building both
ends of the ropes y may be connected with the same and at the ends of the rail run
on small pulleys. Evidently this will in no way disturb the sideway movement of the
chair, but keeps it steady in the longitudinal direction. Further it is to be remarked
that two rails D also may be used, which are carried outside the rails passing carrying
arms to the arm & shown in Figure 2, so that the carriage which is provided with four
wheels may freely slide on the rails along their whole length.
Lastly should be observed, that even the platform may be made of a different shape.
Thus for instance, the bearing ropes may be fixed at its bottom, and the bars u at the
ends of the platform close to the intermediate piece u¹ by which the frames are rendered
superfluous, and the platform may conveniently be provided with a railing and at the
side towards the building with a hinged platform.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same
is to be performed, as communicated to
me by my foreign correspondent I declare that what I claim is :-
First. A portable scaffold or hoist for exterior work on buildings, consisting of a
platform provided with a purchase and one or two rails fixed along the front side
of the house, on which rail, a carriage provided with wheels is adapted to run; four
pulleys, over which the ropes of the platform or into which position the ropes of the
said platform are fixed directly, and two other pulleys over which two ropes are run
fixed at the respective ends of the rails and passing over the respective pulleys last
mentioned, to their respective rope drums on the platform.
Second. In the portable scaffold or hoist above mentioned the arrangement for
fixing the rail passing along the front side of the house, consisting of a T lever the
main arm of which extends along the roofing and is fixed at the latter, one of the other
arms being provided with means by which it rests against the wall, and clasps the
cornice, and of bent arms projecting downwards and supporting the rails.
Third. In the portable hoist above mentioned an arrangement for the support of
the carrying rails consisting of a device for clasping the cornice and of means for
connecting the two parts or arms of the device, a bent arm projecting downward from
the lower arm, the rails being fixed to said arm which is connected with the point of
the device by means of a bracing bar.
Fourth. In the arrangement above described for fixing the rails a device for
moving the outer and inner sets of levers towards or away from each other which
consists of a main T lever, two inner levers arranged inside the said T lever and
having their corresponding ends pivoted to the same nut, their opposite ends being
connected one to the main arm of the T lever and the other to a rod pivoted to a
short arun of the said T lever; a screw fixed in the said nut and passing through the
said short arm which is firmly united to or forms part of the outer or T lever.
Fifth. In the portable scaffold or hoist above described a platform provided with a
ongitudinal shaft having a crank or wheel and two bent shafts connected with this
haft by means of bevel gearing, the said bent shafts supporting the rope drums
he said platform being also provided with two other rope druns geared to the said
pent shafts, above mentioned for moving the platform laterally, ropes for the said
Irums passing over pulleys and fixed at the ends of the rails, or passing round pulleys
ixed at the ends of the rails.

page_text: Sixth. The modified arrangement in which the platform instead of being transported,
on, rails by means of a carriage, with the same carriage, is suspended on two brackets,
similar to those for supporting the rails.
Seventh. The arrangement for holding the platform from the wall of the
building, consisting of adjustable bars directed perpendicularly against the wall,
these bars being provided at the ends toward the wall, with rollers, or covered with
any soft material.
Dated this 28th day of October 1889
HASELTINE, LAKE & Co,
45, Southampton Buildings, London, Agents for the Applicant.