IMPROVEMENTS IN ELECTRICAL BRAKES FOR RAILWAY TRAINS
Year: 1873

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at tho
Office of the Commissioners of Patents, with his Petition, on the
6th February 1873.-A communication from abroad by Messrs.
Garau, Ticozzi, & Co., of Milan, Italy.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN ELECTRICAL BRAKES FOR
RAILWAY TRAINS," a communication, to be as follows:
:-
The principal object of this Invention is the construction of a brake
which differing from all others hitherto devised may be operated in caso
of danger cither by the engine driver or the guard, and at the samo
time will fulfil perfectly the essential conditions of economy, rapidity,
and certainty of action.
The electrical mechanism occupics but little space. The said
mechanism has two bobbins with coils of conducting wire, whose
extremities are fixed to the two poles of a battery. The circuit may bc
established or interrupted by means of a button placed within reach of
the driver. To the frame of the said bobbins is fixed an armature

page_text: pivotted above and free below, and which is composed of two parts
unconnected. This armature is united at its lower end by a joint to a
small hollow cylinder fitted to turn on an axis, and in whose periphery
a longitudinal groove is formed for a part of its length.
Above this part of the apparatus which is the most important part of
the electrical mechanism, there is a drum that turns upon two pivots
supported in the frame of the apparatus, and which carries a cord fixed by
one extremity to the said drum, while its other extremity is provided
with a weight.
Upon the said frame is also pivoted a lever which carries at its upper
extremity a tooth and at its lower extremity a hinged piece. When
the brake is at rest the said tooth is stopped in a notch made in a disc
attached to the aforesaid drum, and the said hinged piece touches below
the curved surface of the said hollow cylinder, and at the side a special
stop formed at the upper part of the said cylinder.
Upon the axis of the said drum is keyed a small bevil pinion which
gcars with a similar pinion on a vertical shaft at the side of the carriage;
this shaft and also the levers attached thereto are exactly like those of
ordinary brakes, and the said shaft is provided at its upper end with a
crank or handle.
When the apparatus is set, that is to say when the weight attached
to the cord is raised by turning tho handle in the proper direction, and
the lever properly adjusted, the button is pressed, the clectric circuit is
closed, the bobbins are magnetized and attract the armature, which
causes the hollow cylinder to turn on its pivots. By this movement the
said cylinder brings its groove into correspondence with the hinged piece
attached to the lever; the said piece being then no longer supported folds
under and escapes from the lateral stop. When this stop no longer acts
upon the said piece, the lever turns and releases the aforesaid disk. The
weight attached to the drum cord can then descend and turn the said
drum, which through the bovil gearing moves the vertical shaft and
thereby closes the brake.
The movement of the armature, which as described, produces the
movement of the brakes, should be caused only by the electric current,
and the possibility of its occurring through any shock to the carriago must
be prevented. For this purpose the said armature is provided with a
small rod which moves up and down in a groove. When the brake is

page_text: at rest, this rod enters a collar fixed to the frame and effectually prevents
the moving of the armature; but when the said armature is attracted
by the magnets the said rod is raised from the collar and permits the
movement of the armature to take place. To open the brake and re-set
the apparatus it is only necessary to turn the aforesaid crank or handle
in the opposite direction; but it is necessary that in this movement the
tooth of the lever should not be arrested by the notch of the disc before
the proper moment, that is to say, before the weight is carried into its
uppermost position; therefore the extremity of the drum's axis which
has a screw thread is provided with a nut; the latter is furnished with a
piece which acts as a stop on an arm of the aforesaid lever. When the
drum has completed its movement and the weight is in the proper
position, the said piece releases the lever arm, and the said lever by its
tooth then engages with the notch of the disc. Moreover, provision is
made for moving the brake by hand by permitting the bevil pinion to
slide on the vertical shaft; it can therefore be moved into or out of gear
with the other pinion through the agency of a clutch operated by a
lever, and by means of this contrivance the brake can be used either as
an electrical brake or as an ordinary brake.