IMPROVEMENTS IN SIGNALS OR ALARUMS FOR DOORS AND WINDOWS, AND FOR SUCH OTHER USES. AS THE SAME ARE OR MAY BE APPLICABLE TO
Year: 1864

page_text: LETTERS PATENT to Thomas Corbett, of Birmingham, in the County of
Warwick, Manufacturer, for the Invention of "IMPROVEMENTS IN SIGNALS
OR ALARUMS FOR DOORS AND WINDOWS, AND FOR SUCH OTHER USES. AS THE
SAME ARE OR MAY BE APPLICABLE TO."
Sealed the 18th April 1865, and dated the 17th October 1864.
PROVISIONAL SPECIFICATION left by the said Thomas Corbett at the
Office of the Commissioners of Patents, with his Petition, on the
17th October 1864.
I, THOMAS CORBETT, of Birmingham, in the County of Warwick, Manu-
facturer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN SIGNALS OR ALARUMS FOR DOORS AND WINDOWS, AND FOR SUCH OTHER
USES AS THE SAME ARE OR MAY BE APPLICABLE TO," to be as follows:-
My Invention consists of the mechanical arrangements herein-after described,
by the use of which a percussion cap or other detonating signal or alarum is
discharged on the opening of the door or window, or other opening to which
my Invention is applied.
In one form of my Invention a metallic plate carries at one end a peg or
nipple, on which a percussion cap is placed, and has jointed to its other end a
lever, the two arms of the said lever being at right angles to one another. A
strong spring presses under the angle of the lever, that part of the said lever
being so formed that when the lever is placed midway between its two posi-

page_text: tions of rest it has no tendency to move in either direction, but when brought
on either side of the position described, it is pressed forcibly to its position of
rest on the-side- to which it has been brought.. "The action of the spring on.
the lever somewhat resembles that of the spring of a clasp knife on the blade.
In applying the apparatus to a door the plate is fixed vertically over the door,
and after the door has been closed the lever is depressed, so as to bring its
lower arm-into a vertical plane, and its upper arin into a horizontal plane.
The lower arm in this position bears against the door at its top; a percussion
cap being placed on the peg or nipple the alarum is ready for use. On the
opening of the door the lower end of the lever bearing against the door is
raised into a nearly horizontal position, when the spring continuing the motion
impels the upper arm of the lever violently against the percussion cap and
explodes it. The alarum may be applied to a window by the plate being fixed
on the upper sash, so as to bring the outer arm, of the lever over the top
of the lower sash. The raising of the lower sash discharges the percussion
cap.
In another modification of my Invention I employ a straight lever, one
arm of which is made to fall upon the percussion cup, by the other shorter
arm being pressed upwards by the spring underneath it. A hook catch is
fixed to the door frame or upper sash, and on the opening of the door or
raising of the lower sash the short arm of the lever is brought against and
depressed by the said catch, the long arm of the lever being at the same time
raised from off the percussion cap on the nipple. As soon as the short. arm
of the lever escapes from the catch the spring restores the lever to its original
position, in assuming which it strikes the percussion cap and discharges it.
In another modification of my Invention the door or lower sash is made to
lift the lever from the percussion cap'; after the door or sash has escaped from
the lever the said lever is made to strike upon the percussion cap by the
action of a coiled spring and to explode the said cap. The part of the lever
on which the door or sash acts is jointed, so as to be capable of yielding in the
direction in which the door closes or the sash falls. By this arrangement the
door may be closed or the sasli shut down after the alarum has been charged
with the percussion cap, without the door or sash affecting the alarum; the
opening of the door or raising of the sash raises the lever and explodes the
percussion cap in the manner described.
I prefer to use percussion caps
which detonatè readily and produce a loud detonation.
The last-described form of my Invention may be charged before leaving the
room or closing the window, and a detonation is produced on the first opening
of the door. or window from the outside.

page_text: My Invention is applicable to shutters and other openings as well as to
doors and windows; although I prefer to fix or attach the alarums to the door
or sash in the manner described, yet, they may be attached in other positions
with the same effect.
$
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Corbett in the Great Seal Patent Office on the
17th April 1865.
+
TO ALL TO WHOM THESE PRESENTS SHALL COME; I, THOMAS
CORBETT, of Birmingham, in. the County of Warwick, Manufacturer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria; by Her Letters
Patent, bearing date the Seventeenth day of October, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Thomas Corbett, Her special licence that I, the said Thomas
Corbett, my executors, administrators, and assigns, or such others as I, the
said Thomas Corbett, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully. might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "Iм-
PROVEMENTS IN SIGNALS OR ALARUMS FOR DOORS AND WINDOWS, AND FOR SUCH
OTHER USES AS THE SAME ARE OR MAY BE APPLICABLE TO," upon the condition
(amongst others) that I, the said Thomas Corbett, my executors or adminis
trators, by an instrument in writing under my, or their, or .one of their
hands and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Thomas Corbett, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
and accompanying Drawings, that is to say :-
My Invention of improvements in signals or alarums for doors and windows,
and for such other uses as the same are or may be applicable to consist in
t-

page_text: constructing and manufacturing. the various descriptions of signals or alarums
in accordance with the following descriptions:
No. alarum, represented by Figs I, II, and IV-are- one and
the same in different positions. A, A, is a metal frame with two shoulders
with a hole in each, which holes hold the two ends of the fulcrum; B, B, bas
two arms nearly in the form of the letter V; H is used as a hammer to fall
upon and explode a percussion cap D, thereby to produce a-report and alarm;
the other arm is used as a purchase lever by which it is set, and is the
part acted upon by the opening of the door, window, shutter, or other opening
body to which it may be applied, thereby releasing the bolt on which the
hammer falls upon the cap and causes, the explosion; C is a steel spring
under B; B, which acts upon the stop of the lever, and gives the force by
which the hammer strikes the percussion cap which causes the explosion;
D is a nipple with the percussion cap upon it; R is a fulcrum upon which
B, B, works.
Fig. II. is a side.view of the alarum with the hammer down upon the
nipple.
Fig. III. is a back end view of the alarum with the lever raised and the
hammer on the nipple.
Fig. IV. is a-side view showing the screws as holding on the plate or slot
with the alarum attached thereto.
No. 2 alarum (Figs. V., VI., and VII.), is a modification of No. 1 alarum:
Fig. V. represents it as seen upon the side and surface or top. G is a metal
frame with two-shoulders, in the holes of which the ends of the fulcrum rest;
His a hammer acted upon by the spring K, working between the shoulders
of the frame G; I is a catch, to be screwed on to the window sash; J is a
nipple upon which the percussion cap is to be placed; K is a spring which
acts upon the hammer H; and † represent the upper and lower sash of a
window; is the lower or bottom sash that when raised the hammer His
made to ascend by a pressure from the catch I, and being suddenly released
causes the spring K to force the hammer down upon the сар, which explodes;
and thereby causes a report and alarm.
Fig. VI. represents a surface or top view of Fig. V.
L, Fig. VII., represents the plate and slot in the same, and used in the
same way as F in Fig. IV.a.
No. 3 alarum consists in the use of a propelling spiral steel or other metal
spring, as seen in Figs. VIII. to XIV.
Fig. VIII., R, R, R, consists of three parts, one at each end forming the
ends, the other supporting the centre of the case Q. Fig. IX.. and guiding

page_text: the bolt or piston.as.hereafter described, thus the ones forming the back and
the one supporting the. centre. have holes in them for the bolt or piston to
work in, thus keeping it in its position and guiding it.while in action, the third
part forming the opposite end near the opening U, Fig. IX. is used as a
target for, the cap to strike.against when fixed upon the nipple end of the bolt
or, piston (see. O, Fig. X.), which thereby explodes and causes the report and
alarm; V represents an opening: in the top of the case Q, Fig. IX., for-the
lever to travel in when released. from the curve by the motion of door or
other opening; W represents a curve in the said opening V, to hold back.the
bolt in which the lever P is fixed, which.lever works in the opening, and when
released from the curve by the motion of the door, 'window, or other opening,
causes the spring to be released, forcing the nipple end of the bolt or piston
(0, Fig. IX.), against the target end R,. thereby exploding the cap and
causing the report and alarm.
Q, Fig. 1X, represents a metal case or covering with closed ends and two
openings, the larger opening U. through which the cap is placed upon the
nipple end of the bolt or piston, the other opening is a slot on the top, curved
at the back end, in which the lever P. works, Fig. X.,-in releasing the bolt or
piston which produces the explosion..
Fig. X. M represents a spiral steel or other wire spring, coiled round and
propelling the bolt or piston N. One end of the said spring is firmly inserted
into the back part or end of the alarum and the other end of the spring is
inserted firmly into the bolt or piston at or near the place where the lever P is
fixed therein. O represents the nipple end of the bolt N, upon which the
percussion cap is placed; P represents the lever fixed into the bolt by
which the bolt is held back, and acts as a trigger in releasing the bolt when
acted upon by the opening door, window, or other moving article.
Fig. XI. shows the under side of the case Q, Fig. IX., with the two slot
holes XX.
Fig. XII. represents the piston or bolt end of the case Q, Fig. IX., and R
Fig. VIII., and also the outer end of the piston or bolt N, Fig. X., and the
lever or trigger P, Fig. X
Fig. XIII. represents a plate turned up at each end, and is intended to be
a permanent fixture by screws, nails, or otherwise, to the place needing pro-
tection, and on which the alarum is placed.
Fig. XIV. represents the: alarum, No. 3, fixed on a door frame.
Alarum, No. 4, Fig. XV. is composed of a plain spring Z, the two ends of
which are drawn near together and a nipple placed near the end of the lower
half or part, the other and upper end X projecting beyond the. end on which

page_text: the nipple is fixed. This alarum is, fixed into a slot Z, A, fastened to the
door frame or window which; when opened,. raises the end X, and suddenly
releasing it explodes the cap placed on the nipple..
Having now described the nature of my said Invention, and the manner in
which the same is to be carried, into effect, I wish it to be distinctly understood
that I do not confine myself strictly to the precise details herein described, as
the same may be varied without departing from the nature of my said; Inven-
tion, but I claim as my Invention the application of steel springs both flat and
spiral, or otherwise, to be used as herein-before described in the construction
and manufacture of: alarums and signals to prevent burglaries, robberies,
poaching, and for signals, and such other purposes as the same may be
applicable to.
In witness whereof, I, the said Thomas Corbett, have hereunto set
"
my hand and seal, this
eight hundred and sixty-five.
day of April, One thousand
THOMAS CORRETT