Improved Locking Device for Window Sashes, Doors, and the like...
Year: 1896

page_text: Date of Application, 25th Mar., 1896-Accepted, 23rd May, 1896
Improved Locking Device for Window Sashes, Doors, and the like...
I JOHN WILLIAM MACKENZIE of Northfield, Oxford Road, Teddington in
the County of Middlesex, Engineer and Patent Agent 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 :-
Reference being made to the annexed drawings in which
Fig. 1 shows the invention applied to the upper sash of a window.
Fig. 2 shows the same applied to the lower sash.
Fig. 3 gives the mechanism in detail.
Fig. 4 is a side view.
My invention, relates to sash or window fittings and has for its object the
combination of a means of lifting or lowering a sliding sash or door to any desired
position and at the same time locking the same.
In the construction of my invention I make use of a toothed piece of metal made
in the shape shown in the drawings at A which is pivoted to the plate C at A¹...
This piece A when free to hang loose does not project through the opening of the-
plate D.
A wedge piece B having a push B' attached to it through the slot C3 in the
front plate C or through a slot in the side plate F and the sash frame and a
lifting hook C 2 or projection situated at the bottom of the slot C 3.
The side plate D'has an opening through which the lock operates. A spring E.
is adjusted to press upon the thick end of the wedge and force it upwards.
In connection with the lock piece a rack with intermeshing teeth may be fitted.
in the frame of the window.
The operation of the device is as follows:-
The wedge B being forced up by the spring E causes the lock piece A to swing.
out of the opening until it reaches its full play or meets with resistance.
It is in ordinary practice made to project three-sixteenths of an inch at its
maximum.
Whenever it stops it is firmly locked by the wedge B and can only be unlocked
by lowering the wedge B by means of the push B'.
When the wedge is lowered the lock piece A swings into the box by its own.
gravity and allows the sash or door to be moved up or down as desired.
The device is fitted firmly in the side of the sash or door, and by preference one.
is fitted on each side of the sash or door.
In order to adapt the device to the upper half of a sliding sash the push B¹ and
the piece C 2 are fitted on the moulding of the sash so as to admit of the lower
half of the sash sliding past upper half thereof. Otherwise the projection of C 2:
on the upper sash would obstruct this operation.
The push B' of the upper sash can be retained in its lower position by means of
the hinged piece H when it is desired to lower the upper sash.
By means of this device all chains, weights and pulleys such as are now in use
for balancing the sash at any particular height may be done away with.
It is also a substitute for the lifting handles or hooks as now required for raising.
the lower sash of a window.

page_text: It is an entirely new means for locking the sash automatically in any position no
effort being required to attain that end.
The locking takes place whenever the sash is stopped, so that I consider
adjustable locking to be a great improvement over the present forms of sash locks
which can only be effective when the window is closed. My device will allow the
Bash to be locked when open to any degree.
Another important advantage of my invention is that it will adjust itself to the
shrinkage of the frame of the sash, and will always hold the sash firmly.
By this means it will prevent the rattle and vibration of the sash which is now
such a common trouble owing to the shrinkage of the sash and frame.
It is especially suitable for bank teller's wickets owing to its ready, automatic
and adjustable locking.
The simplicity of construction, few parts required, little or no wear and tear, and
small danger of breakage or of getting out of order and easy and cheap manufacture,
recommend it as a useful addition to window fittings.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
(1.) In a sash lock, the combination of a pivoted toothed lock piece A, wedge B,
spring E, push B', and lifting hook C 2 as and for the purposes described.
(2.) In a sash lock, the combination of a pivoted toothed lock piece A, wedge B,
spring E, push B', lifting hook C 2, and hinged piece H, as and for the purposes
described.
Dated this 24th day of March 1896.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.