Improved Electric Brake.
Year: 1899

page_text: FOYDAL
DELICATION,
Improved Electric Brake.
CLAUDE WILLIAM HILL, of 80, Manchester Road, Oldham, in the County of
Lancaster, Civil Engineer, do hereby declare the nature of this invention to be
as follows:-
:
The object of this invention is to provide an automatic brake for the control
of machinery, in which the brake is applied by means of a spring and is released
by means of an electro magnet.
To carry the invention into effect I place upon the shaft of the machine, which
is to be controlled, a disc which is keyed to the shaft and so compelled to rotate
with it, but loosely fitted so as to be free to slide along it. On each side of the
disc I place a plate preferably faced with leather or similar substance. One of
these plates is fixed, the other is free to slide along the shaft but is arranged so
that it cannot rotate.
A spring is arranged to press upon the moveable plate so pressing it, the disc,
and the fixed plate all together. The disc is thus held by friction between the
fixed and moveable plates so that it and the shaft to which it is keyed cannot
rotate.
:
An electro magnet is provided and so placed that when energised it attracts the
moveable plate, overcoming the pressure of the spring, releasing the disc and so
leaving it and the shaft to which it is keyed free to rotate.
In order to make the brake small and compaci a number of discs and plates
may be used if preferred, one spring magnet only being required.
Dated this Ninth day of March 1899.
CLAUDE W. HILL.
I, CLAUDE WILLIAM HILL, of Broad Street House, New Broad Street, in the
City and County of London, Civil Engineer, formerly of 80, Manchester Road,
Oldham, in the County of Lancaster, do hereby declare the nature of this in-
vention 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 this invention is to provide an automatic brake for the control
of machinery in which the brake is applied by means of a spring or weight and
is released by means of an electro magnet. Thus the brake is held on and the
machine prevented from moving except when a current of electricity is caused
to flow through the windings of the electro magnet for the purpose of releasing
the brake.

page_text: Referring to the drawings Fig. 1a is the shaft of the machine which is to be
controlled. This shaft is fitted with keys which engage with the disc c.
The disc is thus compelled to rotate with the shaft but is made a loose fit so
that it is free to slide along it. On the two sides of the disc e are the plates d
and e with facings off of leather or similar substance. The plate d is fixed to
the framing, foundations or other convenient part of the machine which is to
be controlled. The plate e is hung from the plated by means of the bracket
and link and to prevent rotation it is provided with lugs which engage the
bolts (the lugs are shown in dotted lines in Fig. 2.)
These bolts which are preferably of non-magnetic material also carry the electro.
magnet of which plate e forms the armature. Brass studs are inserted in
the face of the electro magnet and are allowed to project about '01 of an inch so
as to prevent actual contact of the armature and magnet..
The spring mis arranged to press upon the plate e, pressing it, the disc c and
the plate all tightly together so that the friction on the disc e is sufficient
under normal conditions to prevent it and the shaft to which it is keyed from
rotating. The pressure of the spring may be adjusted by means of the set screw o.
In place of the spring m a weight acting by means of a lever may be used but I
consider the spring preferable. On switching an electric current onto the
electric magnet & the plate e is attracted and pulled away from the disc e which
together with the shaft to which it is keyed is then free to rotate. On interrupt-
ing the electric current the magnet lets go the plate e and the spring m pushes
it back into its former position.
In cases where it is desirable that the holding power of the brake should be
increased without increasing its diameter we may increase the number of discs
and plates. Thus there are shown two dises and three plates in Fig. 3 and other
numbers may be used as may be found most convenient. The indicating letters
in Fig. refer to the same parts as in Fig. 1.
Obviously, having regard to the drawings the number of disces and plates e
with their respective attachments may be varied to suit various cases.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed I declare that what I
claim is
1. The arrangement and combination of parts forming an automatic electric
brake substantially as and for the purpose described.
2. The arrangement and combination of parts in varying numbers as described
with reference to Fig. 3 substantially as and for the purpose described.
Dated this Seventh day of December 1899.
CLAUDE W. HILL