IMPROVEMENTS IN DOOR BELLS OR DOOR ALARMS AND OTHER BELLS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Thomas Eldershaw at the Office of the
Commissioners of Patents on the 2nd May 1878.
THOMAS ELDERSHAW, of Aston, near Birmingham, in the County of Warwick,
Brassfounder. "IMPROVEMENTS IN DOOR BELLS OR DOOR ALARMS AND OTHER
BELLS."
My Invention consists of the construction and arrangement of parts herein-after
described of door bells or door alarms, call or table bells, and other bells.
I will first describe my Invention as applied to a door bell or door alarm.
To the bracket, which is fixed on the top of the door frame and which supports
the bell, an external weighted clapper is jointed. This clapper is jointed to the
upper end of the bracket near the summit of the bell, the said jointed clapper
crossing the exterior of the bell in the direction of a radius. That part of the
clapper which, in its normal position, is situated immediately over the axis of the
bell is expanded and flattened, aud constitutes a bearing plate which is acted upon
to lift the clapper in the following manner:-Jointed to the bracket of the bell is a
hanging lever which is acted upon by the opening door to ring the bell or sound the
alarm. The lower end of the said hanging lever is provided with a jointed arm of
the ordinary kind to permit of the closing of the door. without operating upon the
bell. To the hanging door lever described a curved arm is fixed; this curved arm
projects upwards within the bell, and its upper end passes through an opening in
the summit of the bell, and also through an eye in the supporting bracket of the
bell, to which eye the bell is connected by screwing.
When the parts of the bell are in their normal positions the upper end of the
curved arm of the door lever projects but slightly from the top of the eye of the
bracket above the bell, and the bearing plate described, near the joint of the
weighted clapper, rests upon the upper end of the said curved arm.
When the door, to which the bell or alarm is applied, is opened it acts upon the
hanging lever and presses it inwards. The curved arm of the said hanging lever is
thereby made to rise through the top of the bell, and its upper end by acting upon
the bearing plate of the clapper lifts or turns the latter on its joint. As soon as the
hanging lever escapes from the opening door the said hanging lever falls into its
Paving 271

page_text: normal position, and the weighted clapper being no longer supported also falls, and,
strking the bell near its edge, rings the said bell.
The mechanism described for operating the bell may be applied, with slight
modification, to bells which are sounded by the pulling of a wire, cord, or chain
instead of by the opening of a door.
In applying my Invention to call or table bells I prefer to use in place of the
curved arm described on the hanging lever of the bell a sliding rod working in a
tubular stem supporting the call or table bell. This sliding rod may be lifted to
operate the clapper by means of a hand lever at the foot of the bell; and instead of
a single clapper two or more external clappers may be arranged in the direction of
radii at the summit of the bell, the several clappers being operated upon simultane-
ously by the lifting of the sliding rod in the tubular stem of the bell.