An Improved Automatic Spring Locking Device, Applicable to Toys, Burglar and Fire Alarms, and other Purposes of the like kind.
Year: 1888

page_text: Date of Application, 18th June, 1888
Complete Specification Left, 18th Apr., 1889-Accepted, 18th June, 1889
PROVISIONAL SPECIFICATION.
An Improved Automatic Spring Locking Device, Applicable to Toys,
Burglar and Fire Alarms, and other Purposes of the like kind.
We, ALFRED MILNES HOBSON, Agent, HOWELL BENSON PHILLIPS, Traveller, and
WILKINSON MITCHELL, Estate Agent, all of St. Swithin's Lane, in the City of London,
do hereby declare the nature of this invention to be as follows:-
This invention has for its object a novel construction and arrangement of a spring
locking device, in such manner that whilst it is kept in its closed or locked position
sufficiently firmly against all ordinary attempts to open it, by applying a very slight
force in the right direction it is instantly released and springs up, and in doing so
gives the required alarm if used for the purpose of an alarm, or suddenly exhibits any
concealed figure or object which has been previously kept out of sight, if applied
to a toy.
The improved apparatus consists essentially of a lever pivotted at one end upon a
suitable pin or centre, and having at some distance from this pivot an attachment
to which is fastened a wire or cord the other end of which is fastened to an india
rubber or metal spring, which is fixed upon the frame of the apparatus in such
manner that when the lever is pressed down flat the spring is stretched and the
connecting wire or cord to it is in such a position that a straight line drawn from the
spring to the point of attachment to the lever passes very slightly below the centre of
the fulcrum or pivot.
In this position the tendency of the spring is to keep the lever down, but at the
same time a very small force applied to raise the lever is sufficient to bring the
connecting line above the fulcrum or pivot and the lever is then raised up by
the spring with a gradually increasing force to a more or less vertical position where
it is retained until again pressed down to its original position.
Supposing the invention to be applied to a toy, in which it is desired that at a given
signal and by the application of a very small force a figure or object of any kind shall
open the lid and spring up suddenly from a box in which it has been concealed, we
arrange the novel device described in the box, the pivot being near one end and the
lever lying flat below a hinged cover and having the required figure or object
fixed upon its upper end, the whole being held down by the line of tension of the
spring (which may be preferably of india rubber) being adjusted so that it passes
slightly below the fulcrum or pivot described.
In this position if the outer end of the lever be raised very slightly the lever will
spring up suddenly, throwing open the lid of the box, and displaying the figure or
other object.
In order to raise the outer end of the lever as described, it may be arranged so
that it covers an opening in a false bottom to the box, which opening communicates
with the front or side of the box, so that by blowing into it, or causing a vibration of
the air by a sharp sound, the lever is raised. Or, it may be arranged so that a sharp
blow upon the box, or a sudden vibration, will be sufficient to raise the connecting line
above the fulcrum and set the apparatus in motion. Or, a detent or catch of any
convenient kind may be used, moved by a stud or handle upon the box, or by a string
from a distance.
If the apparatus is used as an alarm it is adjusted as already described so that
any slight movement or vibration will cause the lever to spring up and strike a bell,
or make an electrical contact by which an alarm is sounded, or give other equivalent
notice that it has been interfered with.
Or in case of fire, the expansion of a metal or other rod or plate may be made
to release the lever as described.

page_text: In order to make the apparatus still more sensitive a second independent lever
may be used held down in the same way as that already described, and when
released acting directly or indirectly upon the first or principal lever so as to raise
it slightly when required.
It is evident that the automatic spring device described, may be applied to other
purposes of the like kind, as well as to those described, and that the shape of the lever
may be varied.
Dated this 19th Jan T1000
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicants.
COMPLETE SPECIFICATION
An Improved Automatic Spring Locking Device, Applicable to Toys,
Burglar and Fire Alarms, and other Purposes of the like kind.
We, ALFRED MILNES HOBSON, Agent, HOWELL BENSON PHILLIPS, Traveller, and
WILKINSON MITCHELL, Estate Agent, all of St. Swithin's Lane, in the City of London,
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:
This invention relates to an improved automatic spring locking device, and more
particularly to its application as a burglar alarm.
The operative parts of the invention are a bell or gong; a clapper pivotted at one
end to the base of the device; a spring attached by one end to the base and by the
other to the clapper about half way of its length; and a lever adapted to be engaged
by a moving window-sash or door and to trip the clapper. There may be combined
with the above mentioned mechanism an electric alarm the circuit of which is closed
by the motion of the lever.
In order that our invention, and the means by which the same is to be carried into
practical effect, may be thoroughly understood, we will now describe them in detail,
referring in so doing to the accompanying drawing which is to be taken as part of
this specification and read therewith.
Fig. 1 is a side elevation, and Fig. 2 is a front elevation illustrating the application
of our invention to a two-sash window.
A is a convenient base on which the operative parts of the mechanism are carried.
B is a lever having its fulcrum at b." Its nose b¹ is adapted to be engaged by
either of two studs, 62, 63. The former is fixed to the bottom sash. The latter is an
extension of the lever c, and projects through the bottom sash. It will engage with
the nose as soon as the stud c¹ on the top sash is pressed upon the lever c.
end at e.
D is a bell hung loosely from the bracket d. E is the clapper pivotted by its
F is a spring fixed by one end to the base. It is shewn as a spiral
spring, but may be of any other type, provided that its pull is in a line with the
clapper. The spring is connected by the loop f¹ to the clapper at a point about
half way of its length. The adjacent ends of the lever and the clapper are both
bevelled to corresponding angles.
So long as the lever B is free of the studs 62, 63, the clapper will keep the spring F in
tension, because the line of pull of the latter will pass through the axis of the
clapper-pivot, as indicated by the full lines of the figures. We do not confine
ourselves to having the clapper, when in a state of rest, exactly in the position
above described, inasmuch as the adjacent ends of the lever may be so shaped as to
allow of the latter to throw over the dead centre towards the base A.
As soon as either sash is pushed in the direction of opening it, the lever B is
tripped, and the nose of the clapper moved out beyond the plane in which lies the line
of pull on the part of the spring. The spring F will then cause the clapper to deliver
a sharp blow upon the bell D, and both spring and clapper will assume the position
illustrated by the dotted lines of Fig. 1.

page_text: G. H are a pair of electrical contacts. The former is carried by the lever B, and
the latter is fixed sufficiently near for the circuit to be closed by the motion of the
lever B. The gong of the circuit may be fixed at any distance from the operative
mechanism.
The use of our invention is not confined to windows only, as it is clear from
the foregoing description, that the operative mechanism of the invention may be
applied to a door or other pivotted or sliding parts, due provision being made by
suitable lever-devices for transferring the motion thereof to the lever B.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
:-
1. The combination of lever adapted to be moved about its fulcrum by the
motion of a door or window, with clapper adapted to be thrown by the motion
of the lever and to be brought smartly against a bell or gong by the action of a
spring, as hereinbefore set forth with reference to the accompanying figures.
2. The combination of spring, clapper, and connection between spring and clapper,
so that the clapper is at rest and the spring is in tension at the same time in
consequence of the line of pull on the part of the spring passing through the axis
of the clapper-pivot as set forth with reference to the accompanying figures.
Dated this 18th day of April 1889.
PHILLIPS & LEIGH,
22, Southampton Buildings, Chancery Lane, W.C., Agents for the Applicants.