AN IMPROVED WINDOW CLEANING CHAIR, APPLICABLE ALSO FOR OTHER PURPOSES
Year: 1881

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for an Invention of "AN IMPROVED
WINDOW CLEANING CHAIR, APPLICABLE ALSO FOR OTHER PURPOSES." A com-
munication from abroad by Mrs. Anna Dormitzer, of the City, County, and
State of New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 11th May 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "AN IMPROVED WINDOW CLEANING CHAIR, APPLICABLE
ALSO FOR OTHER PURPOSES." [A communication from abroad by Mrs. Anna
Dormitzer, of the City, County, and State of New York, United States of
America.]
The object of this Invention is to provide a safe and convenient device for use
in cleaning windows and other purposes, which may be temporarily secured to any
window sill or frame to safely support a person cleaning the outside of the
window, and which when not in use can be folded compactly and in little space.
The Invention consists in combination with the platform, folding guards,
supports, steps, and braces of improved devices for securing the chair in position
on a window sill and in an open or folded condition, all of which will be herein-
after fully described.
The chair platform is of suitable size to sit or stand upon, and is provided with
a raised strip fastened along its rear edge to serve as a partial support to the back
guard that is hinged on the face of the platform between the side guards, which
are hinged on the upper edges of the side strips that are securely fastened on the
edges of the said platform. When opened these guards are secured in an upright
position by the engagement of hooks on the back guard in screw eyes or staples
on the side guards. The side strips project below the platform, thereby
strengthening the chair and affording support or points of attachment for certain
of the operating mechanical devices of said chair.

page_text: On the underside of the platform near its front end is a cross brace, which serves
to strengthen the chair and to afford support for a swinging rectangular step frame
which is hinged thereto. Said frame consists of two vertical parallel side bars
securely held together at the top and bottom by cross bars, while from the fronts
of the said side bars at their lower ends are the projecting brackets supporting a
fixed step. On the rear faces of these side bars are secured wedge shaped blocks
faced with leather or other suitable soft material that are designed to take against
the inner face of the window sill or wainscot when the chair is in position, the
leather preventing the sill or wainscot from becoming defaced. The side bars have
their lower ends slotted, and in these slots are pivoted eccentrics which are pro-
vided with handles to operate them. Theso eccentrics are designed to press springs
that are secured on the rear faces of the side bars against the wainscot of the
window when the chair is in position for the purpose of holding said chair more
securely in place, and these springs have on their lower ends wedge shaped leather
covered blocks to prevent the defacement of the wainscot and to afford a better
hold thereon.
Projecting downward from the underside of the platform at the front thereof,
between the upper ends of the frame side bars, is a brace that assists in holding
the step frame in an open vertical position by preventing it from swinging
outward, the top cross bar bearing outward against said brace when the chair is
in position.
Pivoted to the sides of the side bars near their tops are flat curved iron supports
that carry an auxiliary step which swivels between their lower ends, and is held
flat on the top of the fixed step when desired by a stud which is attached on the
end of a spring secured on the underside of said step, and which projects up
through the centre of said step into a corresponding socket in the auxiliary step.
The supports are stiffened by a connecting rod. This auxiliary step is also provided
with two pivoted legs that may be folded in a slot or unfolded and adjusted when
desired, said legs having projecting pins by which they may be readily unfolded.
It is designed to use this step only when the operator desires to reach to the top
of the window or window frame.
In order to secure the chair in place on a window sill a strong clamping device
is arranged on the underside of the platform. This clamping device consists of
a flat bar or block of wood or metal, adjustably held in position by stout metal
angle rods that project from each end of the bar up through longitudinal slots in
either side of the platform, and through plates which are fastened over said slots
and are each provided with one or more bevel-edged perforations for the admission
of said rods, the bevelled edges of said perforations being designed to engage in the
teeth or serrations of the rods and thereby serve to assist in holding the clamping
device in place. On the tops of said rods caps are screwed to prevent the
accidental disengagement of said rods from the plates, while by raising said caps
said rods may be withdrawn for adjustment in any other of the perforations
whereby the clamping bar may be arranged at any desired distance from the step
frame according to the width of the window sill to which the chair is to be
applied.
The front edge of this bar is designed to be covered with leather or other
suitable material to prevent defacement to the window sill or frame. To tho
curved or concave upper edge of this bar are secured springs, whose free ends bear
against the platform and thereby hold said bar from contact with the platform,
and at the same time give the bar some elasticity of movement when being
adjusted. A stout thumb screw is passed from the front rearward through the
brace of the step frame, and has its extremity journalled in a suitable hanger
depending from the platform immediately above the clamping bar, and on this
screw is a travelling nut from which there project or radiate rearward through the
bar two bars to connect said bar and nuts. These bars are pivoted in the nuts so
as to move in vertical planes and incline downward as well as rearward to enter
the clamping bar, where they are secured by a bolt passing through their eyes,

page_text: so that when the screw is turned in one direction by application of the hand to its
thumb piece, the clamping bar is inclined with its lower edge formed with all
necessary force against the outside of the window sill cap, so that the said cap is
clamped firmly between the step frame and the clamping bar, and the window
cleaning chair thereby held in position.
By turning the screw in the opposite direction the lower edge of the clamping
bar is carried rearwards, so that the chair may be removed from its position in the
window. As a further security for the chair when in position for use, and to
afford it the desired support rearward, straight bars or supports are pivoted at one
end so as to move in vertical planes on the inner face of each side strip, and when
not in use are held up in position by means of springs, whose free ends bear
against the pivoted ends of said supports. The upper edges of these supports are
toothed and are designed for the engagement therein of angle dogs that are
journalled in the said side steps, in such a manner that they may be turned so as
to force and hold said supports down upon the outer edge of the window sill,
thereby assuring the perfect security and stability of the chair.
When the chair is in position in a window the back and side guards are elevated
and secured, as herein before described, and a pail for containing water for the
window cleaning is secured by a nib upon it in a loop that also serves as a catch
for a button or hook on the opposite guard when the chair is closed. A standard
is also set in a socket on the edge of the chair, and is provided with a support from
which may be suspended a bucket or other vessel for the convenience of the person
at work upon a window. Should it be desirable for the operator to reach bigher
than is possible from the platform itself the auxiliary step may be raised to
position, and be so secured by the insertion of its legs in sockets made in the face
of the platform and by plate hooks that are pivoted on the same platform and are
caught about the supports. In order to hold the step frame when open down at
right angles to the platform a spring provided with a stud is secured in an end
of the brace of the step frame, which stud engages in a corresponding socketed
plate on the inside of one of the side bars.
When not in use the chair may be folded in small space, and the step frame be
held closed to the platform by a similar studded spring secured on the other sido
bar, and having its stud entered into a corresponding socket plate secured on an
opposite side strip.
I do
This chair is inexpensive to construct, light, durable, strong and secure.
not confine myself to the precise construction of the window cleaning chair, as
herein described, as it is manifest that it may be modified in various ways without
departing from the Invention. In some instances the guards may be dispensed
with and the chair be used as a simple window jack, two of which would suffice to
support a platform for painters or others at work on the outside of a house. The
step frame also may be removed when the chair is designed to be applied to
windows having sills but a little above the floor of the room, and in such case the
front bar through which the screw of the clamping device passes may be corre-
spondingly increased in thickness.
This chair also can be used as an adjustable removable balcony, and be provided
with suitable awning standards or frame, and awning without departing in any
essential point from the Invention.

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
11th November 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "AN IMPROVED WINDOW CLEANING CHAIR, APPLICABLE
ALSO FOR OTHER PURPOSES." A communication from abroad by Mrs. Anna
Dormitzer, of the City, County, and State of New York, United States of
America.
The object of this Invention is to provide a safe and convenient device for use
in cleaning windows and other purposes which may be temporarily secured to any
window sill or frame, to safely support a person cleaning the outside of the
window, and which when not in use can be folded compactly and in little space.
The Invention consists in the combination with the platform, folding guards,
supports, steps, and braces, of improved devices for securing the chair in position
on a window sill and in an open or folded condition, all of which will be hereinafter
fully described.
Figure 1 of the Drawings is a perspective front elevation of the chair in position
with auxiliary step raised; Figure 2 is a perspective rear elevation of the same;
Figure 3 is a perspective view of the chair closed; Figure 4 is a vertical sectional
side elevation of the chair in position; Figure 5 is a front elevation of the same
with auxiliary step raised and guards down, with parts broken away to exhibit
other parts; Figure 6 is a plan of the reverse of the chair partly in section on
line x, x, Figure 4; Figure 7 is a side elevation of a portion of the chair closed;
Figure 8 is a cross section on line Y, Y, Figure 6; Figure 9 is a detailed section of
parts of the device.
Similar letters of reference indicate corresponding parts.
A represents the chair platform of suitable size to sit or stand upon, provided
with a raised strip B₁ fastened along its rear edge to serve as a partial support to
the back guard B that is hinged on the face of the platform A between the side
guards C, C, which are hinged on the upper edges of the side strips C, C', that are
securely fastened on the edges of the said platform A. When opened, these
guards B, C, are secured in an upright position by the engagement of the hooks a
of guard B in the screw eyes or staples 6 of the guards C. The side strips C¹, C¹,
project below the platform A, thereby strengthening the chair and affording support
or points of attachment for certain of the operating mechanical devices of said
chair.
On the underside of the platform A near its front end is a cross brace D', which
serves to strengthen the chair and to afford support for the swinging rectangular
step frame D which is hinged thereto. Said frame D consists of two vertical
parallel side bars c, c, securely held together at the top and bottom by cross
bars c, c, while from the fronts of said bars c, c, at their lower ends are the
projecting brackets c², c³, supporting a fixed step E. On the rear faces of these
bars c, c, are secured wedge shaped blocks d, d, faced with leather or other suitable
soft material that are designed to take against the inner face of the window sill
or wainscot when the chair is in the position shown in Figures 1 and 4, the leather
preventing the sill or wainscot from becoming defaced. The side bars c, c; have
their lower ends slotted, as shown at d¹, and in these slots d¹ are pivoted the
eccentrics E', E', which are provided with handles d² to operate them. These
eccentrics E¹, E', are designed to press the springs E that are secured on the rear
faces of the bars c, c, against the wainscot of the window when the chair is in
position, as shown in Figures 1 and 4, for the purpose of holding said chair more

page_text: securely in place, and these springs E³ have on their lower ends wedge shaped
leather covered blocks d³ to prevent the defacement of the wainscot, and to afford
a better hold thereon.
Projecting downward from the underside of the platform A at the front thereof
between the upper ends of the frame side bars c, c, is a brace F that assists in
holding the said frame D in an open vertical position by preventing it from swinging
outward, the top cross bar c¹ bearing outward against said brace F when the chair
is in position, as shown in Figures 1 and 4.
Pivoted to the sides of the side bars. c, c, near their tops are the flat curved
iron supports F that carry the auxiliary step F which swivels between their lower
ends and is held flat on the top of the fixed step E when desired, as shown in
Figure 1, by a stud f which is attached on the end of a spring f¹ secured on the
underside of said step E, and which projects up through the centre of said step E
into a corresponding socket f' in the said step F. The supports F¹ are stiffened
by a connecting rod f³. This step F is also provided with two pivoted legs g, g,
that are folded in a slot g' when the chair is in the position shown in Figures 4
and 7, and are unfolded and adjusted when desired, as shown in dotted lines
Figures 4 and 5, and in full lines, Figures 1, 4, 5. Said legs g, g, have projecting
pins g by which they may be readily unfolded.
It is designed to use this step F only when the operator desires to reach to the
top of the window or window frame.
In order to secure the chair in place on a window sill a strong clamping device G
is arranged on the underside of the platform A. This clamping device G consists
of a flat bar or block G¹ of wood or metal adjustably held in position by stout
metal angle rods h that project from each end of the bar G', up through longi-
tudinal slots in either side of the platform A and through plates which are
fastened over said slots h, and are each provided with one or more bevel-edged
perforations for the admission of said rods h, as shown in Figures 4, 6, 9, the
bevelled edges of said perforations i being designed to engage in the teeth or
serrations of the rods and thereby serve to assist in holding the clamping
device G in place. On the tops of said rods h caps h² are screwed to prevent the
accidental disengagement of said rods h from the plates k', while by raising said
caps said rods h may be withdrawn for adjustment in any other of the per-
forations whereby the clamping bar G¹ may be arranged at any desired distance
from the step frame D according to the width of the window sill to which the chair
is to be applied.
The front edge of this bar G₁ is designed to be covered with leather or other
suitable material to prevent defacement to the window sill or frame. To the
curved or concave upper edge of this bar G₁ are secured springs m, whose free ends
bear against the platform A, and thereby hold said bar Ğ₁ from contact with said
platform A, and at the same time give said bar G' some elasticity of movement
when being adjusted. A stout thumb screw H is passed from the front rearward
through the brace F³, and has its extremity journalled in a suitable hanger m'
depending from the platform A immediately above the clamping bar G₁, and on this
screw H is a travelling nut H¹, from which there project or radiate rearward
through the bar G¹, two bars n, n, to connect said bar G¹ and nuts H¹. These
bars n, n, are pivoted in the nuts H³, so as to move in vertical planes and incline
downward as well as rearward to enter the bar G', where they are secured by a
bolt n passing through their eyes, so that when the screw H is turned in one
direction by application of the hand to its thumb piece O, the clamping bar G¹ is
inclined, and its lower edge pressed with all necessary force against the outside
of the window sill cap M, so that the said cap M is clamped firmly between the
frame D and the clamping bar G¹, and the window cleaning chair thereby held in
position, as shown in Figures 1, 2, 4.
By turning the screw H in the opposite direction, the lower edge of the clamping
bar G is carried rearwards, so that the chair may be removed from its position in
the window. As a further security for the chair when in position for use, and to

page_text: afford it the desired support rearward, the straight bars or supports P are pivoted
at one end so as to move in vertical planes on the inner face of each side strip C, C¹,
and when not in use are held up in position shown in Figures 6 and 7, by means
of springs p, whose free ends bear against the pivoted ends of said supports P.
The upper edges of these supports P are toothed, as shown at pl, and are designed
for the engagement therein of the angle dogs S that are journalled in the said side
steps C, C, in such a manner that they may be turned so as to force and hold said
supports P down upon the outer edge of the window sill M', thereby assuring the
perfect security and stability of the chair. When the chair is in position in a
window the back and side guards are elevated and secured as herein before
described, and a pail for containing water for the window cleaning is secured by a
nib upon it in the loop a³, that also serves as a catch for the button or hook 62 on
the opposite guard when the chair is closed. A standard W is also set in a
socket c³ on the edge of the chair, and is provided with a support from which
may be suspended a bucket or other vessel for the convenience of the person at
work upon a window. Should it be desirable for the operator to reach higher than
is possible from the platform A itself, the auxiliary step F may be raised to the
position shown or indicated in Figures 1, 4, 5, and be so secured by the insertion of
its legs g, g, in the sockets ( made in the face of the platform A, and by plate
hooks 8 that are pivoted on the said platform A, and are caught about the
support F¹.
In order to hold the step frame D when open down at right angles to
the platform A, a spring T provided with a stud t is secured in an end of the
brace F2, which stud t engages in a corresponding socketed plate t¹ on the inside of
a side bar c.
When not in use the chair may be folded in small space, as shown in Figures 3,7,
and the step frame D be held closed to the platform A by a similar studded
spring T secured on a side bar c, and having its stud t entered into a corresponding
socket plate t secured on an opposite side strip C¹. This chair is inexpensive to
construct, light, durable, strong, and secure. I do not confine myself to the precise
construction of the window cleaning chair as herein shown and described, as it is
manifest that it may be modified in various ways without departing from the
Invention. In some instances the guards may be dispensed with, and the chair be.
used as a simple window jack, two of which would suffice to support a platform for
painters or others at work on the outside of a house. The step frame also may be
removed when the chair is designed to be applied to windows having sills, but a
little above the floor of the room, and in such case the front bar through which the
screw of the clamping device passes may be correspondingly increased in thickness.
This chair also can be used as an adjustable removable balcony, and be provided
with suitable awning, standards, or frame and awning, without departing in any
essential point from the Invention.
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 window cleaning chair constructed substantially as herein shown and
described with platform A, swinging step frame D, supporting fixed step C, and
adjustable auxiliary step F, screw actuated clamping device G, and pivoted rear
supports P, arranged and operated as set forth.
2nd. In a window cleaning chair, the combination with the platform A and step
frame D, of the clamping device G consisting of clamping bar G₁ swinging on
rods h, thumb screw H journalled in hanger m¹, and carrying travelling nut H'
provided with bars n, n, and connected with block G¹, substantially as herein
shown and described, whereby said chair may be secured in position, as set forth.
3rd. In a window cleaning chair, the clamping device G consisting of bar G¹
with attached serrated angle rods, having caps h³, springs m, and screw H
provided with nut H¹, having bars n, n, arranged and operating, substantially as
herein shown and described.
4th. In a window cleaning chair, the combination with the platform A and

page_text: clamping device G, of the slotted plates k¹, substantially as herein shown and
described, whereby the said device may be adjusted, as set forth.
5th. In a window cleaning chair, the combination with the platform A, of the
pivoted toothed bars P and dogs S, substantially as herein shown and described,
whereby additional security and stability is given to the chair when in use, as set
forth.
6th. In a window cleaning chair, the combination with the platform A and
swinging step frame D, of the studded springs T and socketed plates t, substantially
as herein shown and described, whereby the chair is held open or closed as may be
desired, as set forth.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Eighth day of November, A.D. 1881.