Improved Window Casement Fastener.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improved Window Casement Fastener.
I, JAMES MILNE, Milton House Works, Edinburgh, Engineer, do hereby declare
the nature of this invention to be as follows:-
The design or construction of a window casement fastener that not only allows
the window to be opened and fixed securely at any point desired, but that securely
fastens the window shut by merely depressing the lever arm or stay when the window
is shut, the same lever arm or stay being used as a stay to fix the window when
open.
•
The lever arm or stay, and pin upon which it slides are all constructed
radially from the point on which the window hinges.
The lever arm or stay has a quadrant slot formed slightly eccentric to the centre,
upon which it revolves when it is depressed or raised.. The fixing pin which is
fixed to the window frame passes through this slot. The use of this eccentric slot
is, that when the window is shut, it is drawn very tight into its frame by means
of the power acquired by the lever when being depressed. Likewise, when the
window is opened, the eccentric again forces it out of its frame when the lever is
raised, and enables it to be opened with very little effort. The slot is continued
from the end of the eccentric all along the lever arm or stay with small side slots.
As the window is opened, the lever arm or stay slides along the fixing pin which
is attached to the frame, and can be fixed at any point by means of a screw thumb
nut on fixing pin, but more securely by depressing it slightly when one of the side
slots comes opposite the pin, allowing the pin to enter the side slot, and then
screwing the thumb nut, thus securely fixing the window in position.
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1'007
I, JAMES MILNE, Milton House Works, Milton Street, Abbeyhill, Edinburgh,
Engineer, 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:--
My invention has for its object the providing of a simple and efficient window

page_text: casement fastener which will permit of the window being securely fixed at any
desired width of opening, or firmly held in a closed position.
The apparatus consists of a lever arm or stay which is fastened at one end to the
edge of the casement opposite to the hinges, and moves up and down on a pivot or
other convenient form of joint. The lever arm or stay is bent to the same curve as
that described by the above-mentioned edge of the casement in opening or shut-
ting, and it has at the pivot end an eccentric slot which takes the curve of a
quadrant or other portion of a circle whose centre is somewhat nearer the casement
frame when the lever arm or stay is depressed to a vertical position than the
centre of the pivot or other joint. The lever arm or stay may be made with a slot
extending its entire length or part thereof, and running into the eccentric slot
above described, or it may be solid. The lever arm or stay may, if it be slotted,
have on the under side of its upper portion, or if solid, then on its under side, small
recesses capable of receiving a pin which is fixed to the side of the window framing,
and upon which the lever travels backwards and forwards with the opening or
closing of the casement. While the window is open to any extent, the lever arm or
stay is in or approaching a horizontal position. When one of the recesses comes
opposite the pin, the lever arm or stay falls by its own weight, or can be depressed
by hand, till the pin rests in the recess, preventing the further movement of the
casement until the lever arm or stay is raised by hand, so as to disengage the pin
from the recess and permit of the further travel of the casement. The end of the
pin referred to is screwed and fitted with a thumb nut which can be tightened at
any desired position of the lever arm or stay, to give increased firmness of fixing.
When the casement is closed, the lever arm or stay can be depressed to its furthest
extent, when the pin, gradually reaching the extreme point of the eccentric slot,
draws the casement with increasing tightness into the frame. The great leverage
supplied by the eccentric slot is also employed in opening the window-the raising
of the lever arm or stay disengaging the casement with a slight effort, even when
tightly jammed. The arrangement above described, which is intended for an out-
ward-opening casement, can readily be adapted to an inward-opening casement by
attaching the lever arm or stay to the frame and the pin to the casement.
In the drawings Figure 1 represents the lever arm or stay as
seen when
depressed. Fig. 2 the lever arm or stay as slotted. Fig. 5 the lever arm or stay
solid having only the eccentric slot at pivot end. Figs. 3 and 4 the pin and screw
for fixing lever at any desired position. Fig. 6 shows a small section of a case-
ment and window frame with casement fixed open by means of the window case-
ment fastener.
A A the lever arm.
B the pivot upon which the lever arm works.
CD the eccentric slot the end of which at the pivot D where the fixing pin rests
when the lever arm or stay is depressed is nearer the centre of pivot B than the
point C.
EE the recesses which receive the pin F and fix the casement in any desired
position.
F the fixing nin and screw

page_text: lifting the lever arm or stay towards a horizontal position, substantially as above
described and illustrated in the accompanying drawings.
(2) My hereinabove described window casement fastener, all as set forth in the
foregoing description and illustrated in the annexed drawings.