AN IMPROVED SAFETY BRAKE FOR MACHINERY
Year: 1876

page_text: LETTERS PATENT to Edward Primerose Howard Vaughan, F.C.S., of 67,
Chancery Lane, in the County of Middlesex, Patent Agent, for the Invention
of "AN IMPROVED SAFETY BRAKE FOR MACHINERY." A communication from
abroad by Alexandre Athénodore Frécot, of Paris, in the Republic of France,
Engineer
Sealed the 12th May 1876, and dated the 22nd January 1876.
PROVISIONAL SPECIFICATION left by the said Edward Primerose Howard
Vaughan at the Office of the Commissioners of Patents on the 22nd January
1876.
EDWARD PRIMEROSE HOWARD VAUGHAN, F.C.S., of 67, Chancery Lane, in the
County of Middlesex, Patent Agent. "AN IMPROVED SAFETY BRAKE FOR
MACHINERY." Being a communication to me from abroad by Alexandre Athénodore
Frécot, of Paris, in the Republic of France, Engineer.
This Invention consists in an improved safety brake arrangement, by means of
which the motion of steam and other machinery may be arrested in the shortest
possible space of time.
Figure 1 of the accompanying Drawings represents this arrangement applied to
the fly wheel of a steam engine; Figure 2 is a top view of the same.
In these Figures a is the fly wheel, and the driving shaft in its bearings c, c;
e, e, are two levers set one on each side of the fly wheel, and hinged at their outer
ends to the pedestal f; d, d, are brake blocks mounted on the inner sides of the
levers e, e, and facing the rim of the fly wheel; g, g, are cords or chains secured by
one end to the free extremities of the levers e, c, and which after passing over the
grooved pulleys a, a, are terminated by the counterpoises h, h; i is a metallic rod
sustained by the trigger j and connected at with the cords or chains g, g; k is a
lever, the back end of which near the pivot maintains the point of the trigger j.
The opposite extremity of this lever enters a notch formed on the keeper m of the
electro-magnet n which is connected with a voltaic battery placed in any suitable
position; o is a case enclosing the disengaging gear.
When required to set in action the apparatus arranged as above the circuit is
completed by incans of any suitable contact mechanism, and the keeper m being
attracted by the electro-magnet sets free the lever k, the trigger j and the rod i
to which are suspended the counterpoises h, h. The latter in their fall draw

page_text: together the free extremities of the levers e, e, causing the brake blocks d, d, at the
opposite ends to grasp the rim of the fly wheel, and to exercise thereon a pressure
corresponding with the weight of the counterpoises, and the length of the levers on
which they act.
It will be understood that the disengaging gear enclosed in the case o may be of
very small dimensions as compared with those of the brake to which it is applied,
and that if so desired the electro-magnetic attachment may be replaced by a
suitable mechanical equivalent, such for instance, as by pull or push pieces
distributed in any required number over the establishment in which the apparatus
is used.
When the machinery to be acted on is such as cannot be stopped by brake
power, alone, I include in the circuit an auxiliary apparatus similar to the
disengaging gear above described for the purpose of cutting off the steam or other
motive fluid immediately before the operation of the brake. This auxiliary
apparatus which forms part of a fire-alarm and gas intercepter described in the
Provisional Specfication lodged by me in the Great Seal Patent Office on the 21st
day of January 1876, No. 249, is composed of a weighted pulley set on the key of
the inlet cock of the engine, which pulley when liberated by its disengaging gear
carries the key to the closed position, simultaneously or nearly so, with the action
of the main apparatus on the brake levers. If so desired the fire-alarm above
referred to may also be included in the combination.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Primerose Howard Vaughan in the Great Seal Patent Office
on the 17th July 1876.
EDWARD PRIMEROSE HOWARD VAUGHAN, F.C.S., of 67, Chancery Lane, in the
County of Middlesex, Patent Agent. "AN IMPROVED SAFETY BRAKE FOR
MACHINERY." A communication to me from abroad by Alexandre Athénodore
Frécot, of Paris, in the Republic of France, Engineer.
This Invention consists in an improved safety brake arrangement, by means of
which the motion of steam and other machinery may be arrested in the shortest
possible space of time.
Figure 1 of the accompanying Drawings represents this arrangement applied to
the fly wheel of a steam engine; Figure 2 is a top view of the same.
In these Figures is the fly wheel, and b the driving shaft in its bearings c, c;
t, c, are two levers set one on each side of the fly wheel, and hinged at their outer
ends to the pedestal f; d, d, are brake blocks mounted on the inner sides of the
levers e, c, and facing the rim of the fly wheel; g, g, are cords or chains secured by
one end to the free extremities of the levers c, c, and which after passing over the
grooved pulleyse, a, are terminated by the counterpoises h, h; i is a metallic rod
sustained by the trigger j and connected at i with the cords or chains 9, 9; k is a
lever, the back end of which near the pivot maintains the point of the trigger j.
The opposite extremity of this lever enters a notch formed on the keeper m of the
electro-magnet which is connected with a voltaic battery placed in any suitable
position is a case enclosing the disengaging gear.
When required to set in action the apparatus arranged as above the circuit is
completed by means of any suitable contact mechanism, and the keeper in being
attracted by the electro-magnet a sets free the lever, the trigger j, and the rod i,
to which are suspended the counterpoises h, h. The latter in their fall draw
together the free extremities of the levers c, c, causing the brake blocks d, d, at the
opposite ends to grasp the rim of the fly wheel, and to exercise thereon a pressure
corresponding with the weight of the counterpoises, and the length of the levers on
which they act.
It will be understood that the disengaging gear enclosed in the case o may be of

page_text: very small dimensions as compared with those of the brake to which it is applied,
and that if so desired the electro-magnetic attachment may be replaced by a
suitable mechanical equivalent, such for instance, as by pull or push pieces
distributed in any required number over the establishment in which the apparatus
is used.
When the machinery to be acted on is such as cannot be stopped by brako
power alone, I include in the circuit an auxiliary apparatus similar to the
disengaging gear above described for the purpose of cutting off the steam or other
motive fluid immediately before the operation of the brake. This auxiliary
apparatus which forms part of a fire-alarm and gas interceptor described in my
Patent application dated the 21st day of January 1876, No. 249, is composed of a
weighted pulley set on the key of the inlet cock of the engine, which pulley when
liberated by its disengaging gear carries the key to the closed position, simul-
taneously or nearly so with the action of the main apparatus on the brake levers.
If so desired the fire-alarm above referred to may also be included in the
combination.
Having thus described the nature of the said Invention and the manner of
carrying the same into effect, I declare that what I claim is,—
1stly. The levers c, c, hinged in with brake blocks d, d, and counterpoises h, h,
by the fall of which the free ends of said levers are brought towards each other.
causing the blocks to grasp the rim of the fly wheel or its equivalent, the whole
constructed, combined, and operated in manner and for the purposes substantially
as herein set forth and shewn by the accompanying Drawings.
Secondly. The disengaging gear as described and shewn, by means of which
the counterpoises 1, 1, can be instantaneously set free.
In witness whereof, I, the said Edward Primerose Howard Vaughan, have
hereunto set my hand and seal, this Seventeenth day of July, in the year of
our Lord One thousand eight hundred and seventy-six.
E. P. H. VAUGHAN. (L.S.)