IMPROVEMENTS IN APPARATUS FOR LIFTING, LOWERING, AND FIXING WINDOW SASHES
Year: 1878

page_text: LETTERS PATENT to Robert Melville, of Enfield, in the County of Middlesex,
Builder's Foreman, for the Invention of "IMPROVEMENTS IN APPARATUS FOR
LIFTING, LOWERING, AND FIXING WINDOW SASHES."
Sealed the 7th May 1878, and dated the 4th March 1878.
"
PROVISIONAL SPECIFICATION left by the said Robert Melville at the Office
of the Commissioners of Patents on the 4th March 1878.
ROBERT MELVILLE, of Enfield, in the County of Middlesex, Builder's Foreman.
'IMPROVEMENTS IN APPARATUS FOR LIFTING, LOWERING, AND FIXING WINDOW
SASHES."
The object of my Invention is to provide an easy and secure means of raising and
lowering window sashes, whereby the sash cannot be raised or lowered except by
means of a moveable handle or key, thus giving perfect security against burglarious
entry through a window.
I propose to fix in the solid frame of the window on either side a metal frame
divided into two compartments, each compartment having a vertical spindle or
shaft revolving in suitable bearings; at each end of the compartment near the lower
end of each spindle I place a bevil pinion gearing with a toothed wheel set upon
a pin or axle turning in the frame, the other end of each spindle bearing a worm
which will gear into a rack fixed into each sash.
One of the compartments will be higher than the other, and the axle carrying the
toothed wheel working the top sash will cross the compartment, holding the
apparatus in gear with the lower sash.
The action will be as follows:-Upon turning the crank the worm gearing with
the rack of that sash will raise the sash tooth by tooth to the desired height, and
whatever may be the weight of the sash, it will not run down, nor can the bevel
gearing by which the sashes are worked be made to revolve to raise or lower the
sash from within or without, excepting by means of the moveable crauk handle
provided for that purpose.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Robert Melville in the Great Seal Patent Office on the 3rd
September 1878.
ROBERT MELVILLE, of Enfield, in the County of Middlesex, Builder's Foreman.
"IMPROVEMENTS IN APPARATUS FOR LIFTING, LOWERING, AND FIXING WINDOW
SASHES."
The object of my Invention is to provide an easy and secure means of raising and
lowering window sashes, whereby the sash cannot be raised or lowered except by
means of a moveable handle or key, thus giving perfect security against burglarious
entry through a window.
I fix in the solid frame of the window on either side a metal frame or box
divided into two compartments, each compartment having a vertical spindle or
shaft revolving in suitable bearings at each end of the compartment; near the
lower end of each spindle I place a bevil pinion gearing with a toothed wheel set
upon a pin or axle turning in the frame or box, the other end of each vertical
spindle bearing a worm which will gear into a rack fixed on to each sash.
One of the compartments will be higher than the other, and the axle carrying
the toothed wheel working the top sash will cross the compartment holding the
apparatus in gear with the lower sash.
On the accompanying Sheet of Drawing,-
Figure 1 is an elevation or front view of a frame and sash with plate removed, so
as to show position of worm and gearing within the same.
Figure 2 is an end view of the sashes with racks complete.
Figure 3 is a view of the worm and lifting gear as seen from within the frame.
And, Figure 4 is a sectional plan of the above.
A is the upper sash.
B, the lower sash.
C, the window frame.
D, worm and axle for raising sash A..
E, worm and axle for raising sash B.
F, toothed rack secured to sash A.
G, toothed rack secured on to sash B.
H is the winding axle for working worm and axle D.
I is the winding axle for working worm and axle E.
K, moveable handle or crank.
L, bevel wheel secured on to axle H.
M, bevel wheel secured on to axle I.
N, pinion secured on axle D, and in gear with wheel L.
O, pinion secured on axle E, and in gear with wheel M.
P, friction wheels.
The action is as follows:-Assuming that it is desired to lift sash B, I place the
crank K on the shaft I, turn the worm E gearing with the rack G of that sash, and
thus raise the sash, tooth by tooth, to the desired height, where it remains securely
fixed or locked, for whatever may be the weight of the sash it will not run down,
nor can the gearing by which the sashes are worked be made to revolve, to raise or
lower the sash from within or without, excepting by means of the moveable crank
handle provided for that purpose. The sash A is raised or lowered in a similar
manner by placing the handle K on the shaft H and turning worm D.
Amongst the advantages of my arrangement is that of dispensing entirely with
the usual cords and weights, whereby a solid frame may be used in lieu of the
usual box frame, a considerable saving being thereby effected.
Having now described and ascertained the nature of my said Invention, and in
what manner the same is or may be performed, I would have it understood that I
do not limit myself to any dimensions of the various parts of my apparatus, as such

page_text: may be varied according to requirement, and that what I claim as secured to me by
the herein-before in part recited Letters Patent is, in combination with a window
sash, the arrangement of rack worm and lifting gear, substantially as herein-before
described, and shown on the accompanying Sheet of Drawing, for the purpose of
lifting, lowering, and fixing the sash.
In witness whereof, I, the said Robert Melville, have hereunto set my hand
and seal, this Third day of September, in the year of our Lord One
thousand eight hundred and seventy-eight.
ROBERT MELVILLE. (L.S.)