Improvements in Door Bell Mechanism for Use upon Doors of Dwellings and other Buildings.
Year: 1889

page_text: COMPLETE SPECIFICATION.
Improvements in Door Bell Mechanism for Use upon Doors of
Dwellings and other Buildings.
I, HENRY LEACH, a citizen of the United States, residing at Bristol, in the County
of Hartford, and State of Connecticut, U.S.A., Mechanic, 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 my invention is to produce a door bell operated by mechanical means,
that shall be an exact imitation of an electric bell in appearance and sound; and that,
at the same time, shall be simple in construction and efficient in operation. Accord-
ingly I have contrived to connect a push button and a push rod, or slide, with an
ordinary alarm mechanism in such a way as to require only a slight movement of the
push button and slide, similar to that ordinarily necessary with the push button of an
electric bell, by which I disengage the alarm mechanism, and cause the bell to ring
as long as the push upon the button is continued. When the push upon the button is
discontinued, the push rod or slide, and the alarm mechanism instantly become
automatically connected by the action of a spring which retracts the slide, and thus
the action of the alarm mechanism is stopped and the ringing of the bell discontinued.
I, therefore, have all of the utility of an electric door bell without the use of batteries
or connecting wires, which are always more or less troublesome and expensive.
It is only necessary that the push-rod be connected either mediately or immediately
with the alarm mechanism in such manner that a push upon the button, sufficient to
overcome the resistance of the push rod spring and force the push rod inward, will
result in releasing the alarm mechanism and setting in operation its train of gears
and bell strike by force of the main spring.
It is obvious that the push-rod or slide, in some cases, where the alarm mechanism
is placed close to the push-button, on the inside of a partition or door-way, may be
connected directly with some moving part of the alarm mechanism, so that normally
it will constitute a stop, brake, or checking device, to prevent the operation of the
alarm mechanism, and when pushed inward it will be disconnected, and will cease the
stopping or checking function, so that the alarm mechanism will operate, and the bell
will ring as long as the rod continues to be pushed inward and disconnected from its
contiguous moving part of the alarm mechanism.
In some cases it will be desirable to place the bell at considerable distance from the
outside of the door, where the push button is to be operated, as, for example, in the
back end of a hall, or in a back room of a dwelling. "In such cases the push-rod, or
slide, will of course have to be connected by intermediate mechanism, as, for example,
bell wires, with the bell strike, or some other moving part of the alarm mechanism.
As there are a variety of situations to which door bell mechanism is applicable,
there will necessarily be some variations in mechanical details of means for applying
my improvements, the essential thing being in each case to secure such a connection
between the push-button on the outside of a door, and a clattering alarm bell
mechanism within as to produce a perfect imitation of an electric bell that rings as
long as the push upon the button is continued, and no longer.
In the accompanying drawings illustrating one good form of embodiment of my
invention,
Fig. 1 illustrates my door-bell partly in central vertical section, and partly in
side elevation, some of the parts being broken away in order to better illustrate
others.
Fig. 2 is a vertical section thereof, on line x, x, of Fig. 1.
Fig. 3 represents in elevation the push button and its escutcheon on the exterior

page_text: Fig. 4 is a detached view of the holding and releasing dog, together with a
transverse section of the hammer rod.
A designates a portion of the door to which my hell is applied. B designates a
base plate secured to said door, upon which plate is mounted an ordinary alarm
striking mechanism, the base B preferably forming one of the movement plates of
said alarm mechanism, and C designates the companion plate, between which plates
the alarm mechanism is supported. The movement selected consists of a main shaft 5
bearing the ratchet wheel 6 and spring 7, the lantern pinion 8 mounted on shaft 9,
which shaft carries also the verge wheel 10, the pallets 11, bammer shaft 12, hammer
wire 13, and its hammer 14 for sounding the bell, all as in well known alarm
mechanism, and for which other ordinary spring actuated alarm mechanisms may be
substituted.
Upon the movement plate C and surrounding the main shaft 5 I secure the hub 15
upon which the bell D is mounted, and upon the outside of the bell on the main
shaft 5 I secure the winding button 16.
I combine with said alarm mechanism and bell a slide 17 having secured thereto,
and moving with it, the holding and releasing dog 18, which projects laterally from
the body of said slide in the vicinity of the hammer wire 13.
A spring 19 around
the body of said slide 17 is arranged to hold said dog 18 in the path of the hammer
wire when the slide is left free to the action of said spring. As shown one end of the
spring 19 bears upon a hub formed on the base plate B, and the other end of
the spring bears upon the collar 20 affixed to said slide 17. This mechanism is
designed to be attached to a door, or to the casings by the side of a door, provision
being made for the thickness of the door, or other intervening object which separates
the bell upon one side from the push button 21 upon the other side. I have illustrated
the slide 17 as made long enough to reach through the door, and to receive the push
button 21 upon its outer end. I prefer to surround the push button with an
escutcheon 22 as shown.
I have represented the holding and releasing dog 18 in the form of a tapering
round button, so that the body of the slide may be round and fitted in round bearings,
but if the slide was held against rotation it is evident that if the dog projected into
the path of the hammer wire, its essential requisites would be present. The taper or
beveled face is upon that side which first engages the hammer wire when the dog is
moving into the path of said wire. In use the alarm mechanism is wound up and
re-wound from time to time, so that its spring will be ready to operate the hammer
whenever the hammer wire is released. The spring 19 holds the slide and dog in the
path of the hammer wire as illustrated by the full lines in Fig. 4, so as to prevent the
hammer from sounding the bell. When it is desired to sound the bell the push
button 21, which imitates that of an electric bell, is depressed to move the slide 17
and throw the dog 18 into the position indicated by the broken lines in Fig. 4, thereby
removing said dog from the path of the hammer wire and permitting it to vibrate
and sound the bell under the influence of the alarm spring, until the pressure upon
the push button is released and the dog under the influence of the spring 19 again
comes into the path of the hammer wire to arrest its movement.
By my invention the bell and alarm mechanism is adapted to be placed upon the
inside of a room, as for instance upon a door, and to have its hammer wire released
for sounding by means of a dog which slides transversely to the movement of said
hammer wire, which dog may be actuated by means of a push button and returning
spring.
I am aware that prior patents for Burglar Alarms, and for alarm bells for bicycles,
show spring actuated alarm mechanisms with various tripping devices for holding and
releasing said mechanisms, and I hereby disclaim the same.
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 door bell mechanism, the combination of an alarm movement secured within

page_text: doors, a push button on the outside, a push rod or slide between the two, stop
mechanism connecting the push-rod operatively with the alarm movement for instan-
taneously stopping and starting it, like an electric bell, according with the push
and release of the push button, and a spring for automatically retracting the push rod
and causing the stop mechanism to act the instant pressure is removed from the button,
substantially as set forth.
2. In a door bell, the combination of a spring actuated alarm movement and
hammer wire, a slide 17 having a holding and releasing dog 18 arranged to move
transversely to the movement of said hammer wire, a spring 19 for holding said dog
in engagement with said hammer wire, and a push button 21 at the other end of said
slide for throwing said dog out of engagement with said hammer wire, substantially
as described and for the purpose specified.
3. In a door bell, the combination of the vibratory hammer wire, the slide 17, push
button 21 at one end of said slide, a holding and releasing dog adapted to move with
said slide transversely from and to the path of said haimmer wire, said dog being
provided with a beveled face upon that side which first engages the hammer wire
when moving into its path, substantially as described and for the purpose specified.
Dated this 2010 da, of August 1900.
Laku N
COOT an 10
HENRY LEACH.
By Jensen & Son,
77, Chancery Lane, London, W.C., Patent Agents.