Improvements in or relating to Electric Alarms.
Year: 1892

page_text: Date of Application, 13th May, 1892--Accepted, 18th June, 1892
COMPLETE SPECIFICATION.
Improvements in or relating to Electric Alarms.
I RICHARD THORN of 21 High Street, West Norwood in the County of
Surrey, Carpenter, 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 :-
The object of this invention is to cause an electric alarm to ring at any desired
time by the working of an ordinary alarm clock.
And in order that my said invention may be fully understood I will describe the
same with reference to the accompanying sheet of drawings in which
Fig. 1 shews elevation of a clock case with my improvement adapted thereto.
Fig. 2. shews end view of same.
The same letters denote the same parts in both views.
a. shews clock case, b. shews the spindle of an ordinary alarm spring actuated in
the ordinary way by the clock mechanism (not shewn on the drawing) on which I
place the pulley wheel c. having a square hole so as to turn with spindle b. d shews
cord chain or wire one end of which is attached to the pulley c. and the other end
to a flat metal spring i. which forms a contact pieee e. Fig. 2. is another contact
piece or switch pivotted at f. so that the electric circuit may be broken when
desired to stop the electric alarm. g. is a piece of metal through which the
electric circuit is completed when both the pieces d. e. are in contact therewith.
The wires h. h. are in connection with the two poles of a battery through an
electric bell placed where desired which may be at any suitable distance from the
clock.
The action is as follows.
Upon winding up the alarm spring of the clock slightly it will turn the pulley c.
thereby slightly unwinding the cord thereon which will then assume the position
shewn at Fig. 1. and the spring contact d. will be away from the piece of metal g.
also shewn at Fig. 1.
The alarm plate on the clock face is then set in the ordinary way so that the
alarm may go off at the desired time and when the alarm of the clock starts it will
have the power of turning the pulley wheel c. and thus winding the cord, chain or
wire d. thereon, and in so doing will draw the spring contact i. against the piece of
metal 9. and thus close the electric circuit thereby causing the electric bell to
ring and this ringing may be stopped by breaking the circuit by means of the
contact piece e. being turned so as to be clear of the piece g. as shewn dotted at
Fig. 2. which must be turned back again upon winding the alarm clock spring.
I have not shewn the clock mechanism on the drawing as this would be the
ordinary mechanism employed in alarm clocks.
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 improvements relating to electric alarms the pulley e. in combination with
cord chain or wire d. and spring contact piece i. all substantially as set forth.
2. Improvements relating to electric alarms substantially as set forth.
Date : 10th 1
1000
BROWNE & Co.,
9, Warwick Court, W.C., Agents for Applicant.
BROWNE & Co.,
9, Warwick Court, W.C., Agents for Applicant.