MENTS IN ELECTRICAL SELFADJUSTING PENDULUM INDICATORS
Year: 1884

page_text: We FREDERICK KING and WILLIAM PHILLIPS MENDHAM both of the Western
Electrical Works, Narrow Wine Street, in the city and county of Bristol, Manu-
facturing Electricians do hereby declare the nature of our invention for IMPROVE-
MENTS IN ELECTRICAL SELFADJUSTING PENDULUM INDICATORS and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This Invention has reference to certain improvements upon our previous patent
entitled Improvements in electrical self adjusting pendulum Indicators No 3473
and dated the 18th February 1884. We suspend the pendulum from the tips of
2 or more needle points as described in the above mentioned patent. The cores of
the electro magnet we secure to an extension of the metal base in such a way that
they point in an upward direction, i.e. the free poles of the magnet being uppermost.
The armature we fix to the pendulum at such an angle, that upon the current
circulating round the bobbins of wire a side pull is given to the armature, the
distance between the pole ends and armaturo being so regulated that the armature
instead of being attracted up to the magnet and there in all probability sticking,
as. it usually does in this form of Indicator, swings past without touching it
continuing the motion for the space of several minutes in virtue of the needle
points from the tips of which the pendulum is suspended.
This mode of fitting up our Indicator we illustrate by the accompanying
drawings.
Instead of placing the magnet exactly behind the shaft of the pendulum we
sometimes place it at the side of the pendulum in which case we fix the armature
directly behind the shaft of the pendulum. In either case the action of the magnet
on the armature is similar.
Another plan we sometimes adopt is to fix the cores of the magnet with their
bobbins of wire to the tube carrying the pendulum in such a way that they lie
exactly behind the shaft of the pendulum. and point in a downward direction (the
armature being fixed to the metal base and a little to one side of the magnet poles)
so that upon a current of electricity circulating round the bobbins, they move with
the swinging pendulum and pass the fixed armature without touching it.
Referring to the drawings. Figs 1 & 2 in which the letters refer to the same
parts in each, A is the metal frame upon which the bobbins B B are mounted,

page_text: :
C is the support fixed into the upper part of the metal frame and carrying the
needle points (shown inside the tube) D is the tube resting on the tips of the
needle points and carrying the pendulum F, E is the armature fixed on the
underside of the tube D and at an angle with the shaft of the pendulum.
Having now particularly described and ascertained the nature of our said
Invention, and in what manner the same is to be performed, we declare that what
we claim is
1 The construction of a pendulum Indicator in which the soft iron armature is
fixed to the pendulum in such a relation to the magnet poles, that upon the electric
current circulating round the poles of the magnet a side pull is given to the
armature which is attracted towards the poles and swings past them without
touching, substantially as hereinbefore described.
2 The combination of two or more needle points as a means of suspension with
a swinging pendulum substantially as herein before described.
3 The arrangement of a pendulum Indicator the armature of which upon
receiving a side pull is attracted towards the poles of the magnet and swings past
them without touching substantially as herein before described.
4 The arrangement of a pendulum Indicator in which the armature being fixed,
the magnet receives the side pull and swings past the armature, without touching
it substantially as hereinbefore described.
5 The construction of a pendulum Indicator in which the armature being fixed,
the magnet receives the side pull and swings past the armature without touching it
substantially as herein before described.
6 The combination in a pendulum Indicator of needle points as a means of
suspension for the pendulum and an armature so placed relatively to the magnet
poles, that upon a current of electricity circulating round the poles of the magnet,
the armature, moving towards the magnet poles by virtue of magnetic attraction,
does not touch the magnet poles but passes them without touching substantially as
hereinbefore described.
7 The combination in a pendulum Indicator of needle points as a means of
suspension for the pendulum and an armature so placed relatively to the magnet
poles, that upon a current of electricity circulating round the poles of the magnet,
they moving with the pendulum towards the fixed armature by virtue of magnetic
attraction do not touch the armature but pass it without touching substantially as
herein before described.