Improvements in or relating to Door or other like Bells.
Year: 1890

page_text: Date of Application, 22nd July, 1890-Accepted, 6th Sept., 1890
COMPLETE SPECIFICATION.
Improvements in or relating to Door or other like Bells.
A communication from abroad by FREDERICK SANDERSON, of Chicago, in the County
of Cook, and State of Illinois, United States of America.
1, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, and 23, High Holborn, in the County of Middlesex,
Civil Engineer, 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 stateinent:-
The invention relates to that class of door bells which are applicable to either
doors or door jambs, or other similar situations, without making any radical change
in the operative mechanism.
One object of the invention is to arrange the pivotal centre of an elbow lever
which operates the hammer in relation to the pivotal centre of the elbow levers con-
nection with the push button, so that a very slight push upon the push button will
cause the hammer to give two distinct strikes upon the bell.
Another object is to provide two arms to the hammer operating elbow lever,
which arms contact with stops on the frame to which the elbow, lever is pivoted,
for the purpose of limiting the motion of said elbow lever, for the purpose of causing
a quick retraction of the hammer from the bell, after it has struck.
Another object is to so connect the push button and the lever which operates the
hammer that the connection will be in alignment by the introduction of a bifurcated
pitman, which permits the hammer to vibrate vertically within the space between the
two arms of the bifurcation of said pitman.
Another object is to provide a self centreing part, to the side of the apparatus where
it contacts with the door, which also acts as a guide for part of the operative mechanism,
as will be fully explained hereinafter.
These objects are obtained by the mechanism illustrated in the accompanying
drawings, in which,
Figure 1 is a vertical centre section on line A, B, Figure 2, with operative mechanism
in perspective.
Figure 2 is a horizontal centre section on line C, D, Figure 1, with operativo
mechanism and the frame to which the bell is attached in perspective.
Figure 3 is a detached top view of the frame or standard, to the outer end
of which the bell is secured, and into which the lever for operating the hammer
is pivoted.
Figure 4 is a detached side view of the elbow lever for operating the hammer,
together with its spring arm with hammer attached.
Figure 5 is a perspective rear view of the base by which all the apparatus of the
bell is attached to the door. Figure 5 also shows self centreing device and guide for
button rod.
Figure 6 shows, respectively, side and top detached views of bifurcated connection
between push button rod, and hammer operating elbow lever.
Figure 7 shows part of the door with hole, and position of self centreing device as
will be described.
Similar letters refer to like parts in the several views.
E is a bell which is secured to the end of frame F by means of a screw a.
The frame F, Figure 3, is secured to the base plate G at b. The plate G is
circular in shape, Figure 5, and in Figures 1, 2 and 3 is shown a flange c around
its outer edge. This plate G is provided with screw holes d, Figure 5, which are

page_text: occupied with wood screws for firmly attaching it to its proper position on a door
or any other place desired.
The head of frame F is slotted out near the end at e and into this slot is
pivoted an elbow lever H. upon a pin f, Figures 1 and 2.
The lever Hvibrates in a vertical direction, and it is provided with two pro-
jections and which contact with shoulders and on the head of the frame F,
hus limiting the movement of the elbow lever H.
One arm of elbow lever H. is formed by the spring rod k, which has the
hammer secured to its outer end. To the short arm of elbow lever H is
pivotally attached to a pin 1, Figures 1 and 2, the bifurcated connection m,
Figure 6, and the opposite end of connection m is held in position and slides in
notches, cut into the sides of the slot J, which slot is cut through the plate G,
Figures 2 and 5.
The push button K is of the usual form, with shoulder, and operates in the usual
escutcheon K'.
To the inner end of the push button is attached a small rod o whose opposite
end is guided and slides in the hole in the U-shaped part L, Figure 5, which
is at the centre of the rear side of plate G.
This U-shaped part acts also another purpose-
When the door-bell is to be attached, a hole N is bored through the door. The
dimensions of the part L from any one of its corners to the diagonally opposite
corner is slightly larger than the diameter of the hole N so that the part. I is forced
into the hole N and thus centres the plate G, together with the attached operative
mechanism, as shown by Figure 7, thus, but few screws are required to secure
plate G to a door, and it is prevented from even slightly changing its position
when once in place.
In operation, one push inward upon the push button K causes the rod o to
contact against the end of the bifurcated connection m, the connection m being
pivoted to the elbow lever H at 7 in such a relative position to pin that when
the several operative parts of the apparatus are in normal position, when at rest,
the two centres and are almost in line with a centre line from pivot to rod o
and the push button, and, for this reason, a very small inward movement of the
push button will cause the elbow lever to turn on its pin f and through the medium
of its spring arm cause the hammer I to quickly rise and strike the inside top
of the bell, as shown by the dotted lines, Figure 1.
As soon as the pressure is removed from the push button K, the hammer I, by
its own weight, falls and strikes a second blow upon the inside of the bell at the
bottom, Figure 1.
The hammer I and its spring arm k, in both their upward and downward
strokes, pass between the bifurcations of the connection m, so that pressure upon
the push button is transmitted centrally and with no side draft to the hammer
operating lever H.
The hammer is instantly retracted from the bell after it has struck by means
of the spring arm k The elbow lever H does not vibrate enough to throw the
hammer against the bell at either the top or bottom stroke, but when the ends of
the arms and contact with the shoulders and j, limiting the stroke of the
elbow lever the momentum of the hammer I springs the arm enough to cause
the hammer to contact with the bell, but as soon as the blow is delivered the bent
spring arm instantly withdraws the hammer, when it stands at the top or bottom
of its stroke in the relative position shown in Figure 1.
The gravity of the hammer I acting upon the elbow lever H, through the medium
of the connection m and rod o always holds the push button outward with its
shoulder in contact with the escutcheon K¹.
It will be noticed, in Figure 1, that the pivotal centre of lever H, and the
pivotal centre of the end of bifurcated connection m are almost in line with the
longitudinal centre of the push button rod o, when the mechanism is at rest, and,

page_text: on this account, the elbow lever H starts a little hard, at first pressure upon the push
button, but when started, it turns suddenly upon its pivotal pin f, causing the
hammer I to deliver a quick upward blow upon the bell, the natural result of which
is that the person pushing the button, after hearing the sound of the bell, will instantly
release the pressure, when the gravity of the hammer descending will cause the second
blow on the bottom of the bell, thus, a quick succession of blows can be delivered on
the hell by means of this simple arrangement of mechanism.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. In a door bell or the like, the elbow lever H pivoted in slot e of frame F,
spring arm & attached to said lever H, hammer I attached to said arm k, bifurcated
connection m pivoted at to said elbow lever H, spring arm kand hammer 1 operating
vertically between the bifurcations of said connection m, in the manner and for the
purpose substantially as shown and described.
2. In a door bell or the like, the elbow hammer arm operating lever H provided
with stop arms g and h, said elbow lever H being limited in its motion on pin ƒ by
said stop arms and contacting with shoulders i and j for the purpose herein-
before described.
3. In a door bell or the like the bifurcatel connection m pivoted at one end to
elbow lever H and supported and operating at the opposite end in notches n in the
sides of slot J of base plate G, one end of rod o contacting with the end of connec-
tion m, as shown, said rod o having attached at its opposite end a push button K, all
for the purpose of connecting push button K with and operating elbow lever H by
pressure on said push button K.
4. In a door bell or the like, the described U-shaped part I secured to the rear of
the base plate (, having the described hole p in which operates the rod o, said
U-shaped piece I acting also to hold the circumferential centre of base plate G central
with the longitudinal centre of cylindrical hole N, which is bored through the door in
The manner described.
5. In a door bell or the like the frame F provided with contact shoulders and j,
elbow lever H having arms and which contact with said shoulders and j, and
limit motion of said elbow lever H, spring arm k attached to said lever H, said spring
arm having hammer I, attached to its onter end, bifurcated connection m pivotally
attached to elbow lever H at 1, hammer I and spring arin operating vertically
between the bifurcations of connection m, when the whole is used in combination
with press button K and its rod o, in the manner substantially as shown and
described.
T: 01-4ave of Lul 1800
WM. P. THOMPSON & Co.,
Agents for the Applicant.