IMPROVEMENTS IN SAFETY WINDOW CLEANING CHAIRS
Year: 1878

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
SAFETY WINDOW CLEANING CHAIRS." A communication from abroad by
Anna Dormitzer, of New York City, United States of America.
Sealed the 26th July 1878, and dated the 28th February 1878,
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 28th February 1878.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Mid-
dlesex, Patent Agent. "IMPROVEMENTS IN SAFETY WINDOW CLEANING CHAIRS,"
[A communication from abroad by Anna Dormitzer, of New York City, United
States of America.]
The object of the Invention is to provide a convenient device which may be
temporarily attached to a window sill for supporting a person while cleaning the
outside of windows, and which after use may be compactly folded together so that
little room is required for storing it.
The Invention consists in a combination of a platform and folding guards and
supports, which will be herein-after more fully described.
The platform is of a suitable size to stand on, and has a guard hinged to one end,
and supported and stiffened when unfolded by a piece which is attached to the end
of the platform, and projects a short distance above the platform and also beyond
its edges. Upon the opposite end and opposite side of the platform is secured
another piece, from which strips extend above the under surface of the platform at
its edges for receiving a rod, upon which swings a brace, and for receiving another
rod, upon which the step support is pivotted. A step is attached by brackets to the
support, and between these brackets a board having a slot is fitted. This board is
clamped to the support by a bolt, which is provided with a wing nut. Two slotted
pieces are attached to the board by means of a bolt, also provided with a-wing nut,
and the lower edges and ends of these pieces are provided with spurs that project
[Pries G21

page_text: into the floor and window casing when the device is in use. A cord is attached to
the brace a short distance from its pivot, and runs through an aperture in the piece
attached to one end of the platform, and is fastened by placing it under clips and
in a fork, both of which are secured to said piece. Rods pass through the ends of
the piece, which support the guard, and run forward parallel with and a short
distance from the side of the platform beyond the opposite end of the platform, and
are bent backward or return upon themselves, and attached to the edge of the plat-
form above the other piece.
Upon each of the rods is placed a sleeve, which is provided with a thumbscrew
for binding it in any desired position on the rod, and to each sleeve a curved rod is
attached. These rods are formed on a reverse curve, and the rods on opposite sides
of the platform are oppositely arranged in respect to each other.
There are several holes in the side pieces for receiving the rod or step support, so
that the brace may be adapted to walls of different thickness.
The apparatus is put into position for use by unfolding it, and placing the plat-
form on the window sill and drawing the cord so as to bring the brace into contact
with the outside of the wall. The cord is fastened by putting it under the clip and
into the fork. The curved rods are now brought against the wall, one on the inside
and the other on the outside on each side of the window, and are clamped by the
thumbscrews. The slotted piece is now moved downward until its spurs enter the
floor, when it is clamped by turning the wing nut; the guard is raised into a vertical
position, and the apparatus is ready for use.
There is ample room on the platform for the person cleaning the window, and
also for the various articles required in cleaning.
.The rods on the outside of the wall inay be employed as guards to prevent the
person from falling from the platform, or it may be dispensed with altogether.
Vessels for containing the materials for cleaning are suspended from the bent rods
above mentioned by means of hooks.
The apparatus herein described facilitates the cleaning of windows, and renders
the operation safe.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
28th August 1878.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN SAFETY WINDOW CLEANING CHAIRS." A com-
munication from abroad by Anna Dormitzer, of New York City, United States of
America.
The object of this Invention is to provide a thoroughly safe and life-preserving,
as well as convenient device for use in cleaning windows, which may be temporarily
attached to any window, and support any person safely while cleaning the outside
windows, and which after use may be compactly folded together, so that little room
is required for storing it.
The Invention consists in a combination of a platform, folding guards, and
supports, and vessels employed to hold the necessary water and cloths, all of which
will be herein-after more fully described.
Figure 1 of the accompanying Drawings is a perspective view of the improved
step chair, showing it in position for use; and Figure 2 is a side elevation of the
chair detached from the window.
Figure 3 represents a modified form of the apparatus.
Figure 4 is a vertical section taken on line x-x, in Figure 3.
Figure 5 is a plan view.
Figure 6 is an inverted sectional plan view; and Figure 7 is a detail view of
joint between the seat and lower support.
Figure 8 is a front elevation of a different form of chair.
Figure 9 is a vertical section taken on line x-x, in Figure 8; Figure 10 is a
plan view.
Figure 11 is an inverted plan view; and Figure 12 shows the chair folded up.
A, Figure 1, is a platform of a suitable size to stand or sit upon, and B is a guard
hinged to one end of the platform, and supported and stiffened when unfolded by a
piece C, which is attached to the end of the platform, and projects a short distance
above the platform, and also beyond its edges. Upon the opposite end and opposite
side of the platform A a piece D is secured, from which the strips E extend along
the under surface of the platform at its edges for receiving the rod a, upon which
the brace b swings, and for receiving the rod c, upon which the step support d is
pivoted. A step e is attached to the support d by means of brackets f, and between
these brackets a board g having the slot h is fitted. The board g is clamped to the
support d by a bolt i, which is provided with a wing nut j. A piece / is attached
at right angles to the outer face of the slotted board g at its lower end, and is
provided with spurs that project from its under surface. A cord m is attached to
the brace ba short distance from its pivot, and runs through an aperture in the
piece D, and is fastened by placing it under the clip n and in the fork o, both of
which are secured to the piece D. Rods F pass through the piece C, in which they
are fastened, and run forward parallel with and a short distance from the side of
the platform A, beyond which they project several inches, and are bent backward
or returned upon themselves, and attached to the end of the platform above the
piece D.
Upon each of the rods F is placed a sleeve o', which is provided with a thumb-
screw p for binding it in any desired position on the rod, and to each sleeve a
curved rod is attached. These rods are formed on a reversed curve, and the rods
on opposite sides of the platform are oppositely arranged in respect to each other.
There are several holes a¹ in the side pieces E for receiving the rod a, so that the
brace 6 may be adapted to walls of different thicknesses.
The chair is put into position for use by unfolding it and placing the platform A
on the window sill, and drawing the cord m so as to bring the brace b into contact
with the outside of the wall. The cord is fastened by putting it under the clip n

page_text: and into the fork o. The rods q are now brought against the wall, one on the
inside and one on the outside on each side of the window, and are clamped by the
thumbscrews p, and may be connected by a chain pl. The piece g is now moved
downward until its spurs enter the floor, when it is clamped by turning the wing
nut j; the guard B is raised into a vertical position, and the chair is ready
for use.
There is ample room on the platform A for the person cleaning the window to
stand or sit upon, and also for the various articles required for cleaning, which are
held by small cups u¹, or receivers that are hooked to the two rods F.
The rods q on the outside of the wall may be employed to keep the platform A
more firm, and ensure the feeling of perfect ease and security.
In the modification shown in Figures 3 to 7 inclusive the frame g¹ takes the
place of the board g in Figure 1, and is clamped to the support d by bolts i. A
chain m¹ is attached to the brace 6' a short distance from its pivot, and runs
through an apertured piece of wood e secured to the under side of the platform A,
and attached to the hooked end of a bolt n¹ that extends through the piece D to
receive a wing nut o%. By means of this bolt and chain the brace b¹ is drawn
against the wall so as to securely hold the platform A against downward
pressure.
Instead of employing a bolt with a hook head, as described, I may employ a long
screw a², Figure 6, journalled in the front piece D, and in a block 62 attached to the
under side of the seat, said screw having a winged head for convenience in turning.
Upon the screw I place a travelling nut c¹, which is provided with two snap hooks
for receiving the chain m'. The end of the screw a' may be squared to receive a key
for turning it, in which case the screw will not project beyond the surface of the
piece D.
Instead of a single central screw I may place one at each side of the platform,
and attach one chain to each nut, but the single screw is preferable, as both sides of
the brace may be drawn into contact with the wall at one operation.
The back or guard B is provided with screws or studs e¹, which are engaged by
the curved spring wires f¹, which are attached to the seat A, and serve to support
and render secure the back or guard B. The wires also serve to hang the vessels
which contain the articles used in cleaning the windows.
The board d may be provided with studs or screws, which may be engaged by
curved wires, as in the case of the back B. The edges of the platform A are grooved
to receive the rods or braces q, which are secured by the half round metallic covers o³,
which are fastened to the edges of the platform by means of screws. The covers
are provided with thumbscrews p¹ for holding the braces in any required position,
and they are also provided with spring catches or detents, which prevent the braces
from escaping from the grooves in the edges of the platform. The braces q are bent
at a right angle, so that they may engage the inner surface of the wall at the sides
of the window.
An auxiliary step A² is hinged to the front edge of the platform A, and when in
use is supported by the braces q, as shown in Figures 4 and 5.
The chair is put into position for use by unfolding it, and placing the platform A
on the window sill, and drawing the chain by means of the screw, so as to bring
the brace b¹ into contact with the outside of the wall. The braces q are now brought
against the inner side of the wall, and are clamped by the thumbscrew p'. The
frame g' is now inoved down until the spurs with which its feet are provided enter
the floor. The guard or back B is raised into a vertical position when the chair is
ready for use.
The chair herein described facilitates the cleaning of the windows, and renders
the operation safe.
When it is desired to store away the chair the guard B is folded against the
upper surface of the platform, and the support d is folded over it after having
moved the part g' upward as far as possible. The chair is thus put into convenient
form for carrying from place to place, or for storage. By modifying the device
2

page_text: the platform may be sustained by the inside support, the brace, and the two inside
rods զ alone.
In the modification shown in Figures 8 to 12 inclusive A is a platform of
suitable size to stand or sit upon, having at its front edge a narrow board or cleat B*,
which is joined to it at right angles, and projects downward; and having at its rear
edge a similar cleat or board C, which projects upward at right angles.
Two cleats D' are attached to the under surface of the platform A, one at each
side edge. In these cleats there are several holes a¹ for receiving a rod b', which
supports the brace E. Chains F are attached to the brace E, and pass through a
block G attached to the bottom of the platform, and are received by hooks on the
travelling cut that is placed on the screw d, which is journalled in the block G*
and in the cleat B, and is provided with a winged head e, by which it may be
turned.
The rod 64, upon which is placed the brace E, may be inserted in any of the
holes a to accomodate the device to walls of different thicknesses.
The platform A is provided with two levelling screws f, which bear upon the
window sill, and render the platform level and secure. To the under side of the
platform A near the cleat B is hinged a support H4, which when unfolded presses
against the cleat B*.
The window sill and the wall below the window sill are clamped between the
brace and the support H. A step I* is secured to the lower part of the support H*
by means of brackets g, and an auxiliary step is connected with the support H*
by curved straps it, which are pivoted to the edges of the support and also to the
ends of the step.
The auxiliary step his provided with folding legs j, and it may be raised above
the platform A, and supported by the said legs and by the curved straps 4, which
are received in slots in the end of the platform, and are secured by hooks that are
pivoted to the top of the platform.
The support His provided with two springs 1, one at each end, which are
operated by eccentrics m*, so as to bring them to a bearing on the inner surface of
the wall.
The platform A has near each of its side edges an aperture for receiving the
screw of the standards n*, which are designed to be grasped by the hand to steady
the person using the window cleaning chair. To the upper side of the platform
near the outer or back edge, and inside of the cleat C, the back or guard J' is
hinged. From the edges of the back two pins of project to engage the detent
springs p¹ that are secured to the platform, and hold the back in a vertical position.
The detent springs consist of a wire that is curved and formed into a loop which
receives the pin when the back is raised.
The auxiliary step is designed to afford a means of reaching the upper portion of
the window.
When the device is not in use it may be compactly folded together, so that it
requires little room for storage.
The springs which are used to support the back may also be used to support the
vessels used to contain the materials employed in cleaning the windows.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is,—
1st. A folding window chair or scaffold, consisting essentially of the pieces A, C,
hinged guard B, rods F, q, having device m, n, o, b, and the piece d provided with
slide piece g, all arranged as shown and described.
2nd. The combination of the side rods F and the adjustable curve rods g with
the platform A, substantially as shown and described.
3rd. The cord m and fastenings n, o, in combination with the adjustable brace b,
substantially as herein shown and described.
4th. The support d having the adjustable spur piece g in combination with the
platform A, as herein shown and described.

page_text: 5th. As a new article of manufacture a safety window cleaning chair having an
adjustable secured back or guard, as herein shown and described.
6th. In a window cleaning chair the combination of the hooked screw n¹, chain m³,
and brace b', substantially as shown and described.
7th. The hooked wire f' in combination with the folding back or guard B, having
studs e¹, substantially as shown and described.
8th. The right-angled braces q, in combination with the platform A, having
grooved sides, and the metal covers o³ having thumbscrews p¹, substantially as
herein shown and described.
9th. The combination of the auxiliary step A³ with the platform A, as herein
shown and described.
10th. The combination of the levelling screws f* with the platform A*, substan-
tially as herein shown and described.
11th. The combination in a window cleaning chair of the standards n' with the
platform A, as herein shown and described.
12th. The combination of hinged brace E, chains F, screw d', and travelling nut
c, with the platform A, as herein shown and described.
13th. The combination of the auxiliary step h with the support h* and platform
A', as herein shown and described.
14th. The combinations of the springs and eccentrics m* with the support H*,
as herein shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Twenty-eighth day of August, in the year of our Lord
One thousand eight hundred and seventy-eight.
AT
D