IMPROVEMENTS IN BREAKS, FOR RAILWAY AND OTHER CARRIAGES
Year: 1858

page_text: (This Invention received Provisional Protection, but notice to proceed with the
application for Letters Patent was not given, within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by James Murdoch at the Office of
the Commissioners of Patents, with his Petition, on the 21st January
1858. A communication from J. H. Clément, of Paris (France).
I, JAMES MURDOCH, of 7, Staple Inn, in the County of Middlesex, Patent
Agent, do hereby declare the nature of the Invention for "IMPROVEMENTS IN
BREAKS, FOR RAILWAY AND OTHER CARRIAGES," a communication from 'J. H.
Clément, of Paris (France), to be as follows:-
This Invention consists of certain improved arrangements for breaks for
railway and other carriages, which are based upon the same principle as those
described in a Patent for the same object granted to Jules Hyppolite Clément,
dated 17th October 1855, No. 2318, and which may be briefly described as
follows: "A shoe being let drop upon the rim of a wheel and at a very
acute angle, is drawn round during a portion of the rotation of the wheel so as
to grip it. Whilst thus being drawn round it acts upon a strong spring, the
reaction of which forcibly presses the shoe against the rim of the wheel."
+
"To limit the distance through which the shoe shall be drawn, a stop or
support arrests it at a short distance above a line passing through the axes of
the wheels. The object of this short distance is that when the sliding of the
wheel ceases, the reaction of the spring may impart a retrograde movement to
the wheel."
In the improvement represented in Figure 1 the reaction spring forms a
part of the great connecting rod instead of being placed on one side (shoe.in
the raised position). a is the great connecting rod carrying the back shoe f.
and a' the little connecting rod carrying the front shoe f; b, guide bar having

page_text: a collar moving stiffly along it, which has a spring to keep the fore shoe at a
short distance from the rim of the wheel when the wheel is in motion; c, back
stirrup, stopping the back shoe a little above the line joining the centers of
the wheels; c', fore stirrup maintaining the fore shoe in contact a little below
the line joining the centers of the wheels, and open below to allow the shoe to
descend when after the action of the breaks the engine moves backwards; e,
main reaction spring; i, sliding box supporting the two connecting rods upon
the guide bar.
In Figure 2 the little connecting rod and one of the shoes are suppressed
(shoe shown as lowered). a, little connecting rod supporting the pivot; a¹, a³,
large connecting rod carrying the shoe f; c, fore stirrup serving the same
purpose as in Figure 1; c, back, stirrup, with a spring attached to the frame
of the carriage, and serving to keep the stirrup at a distance from the axle
when the wheel is in motion; e¹, spring supporting the apparatus whilst the
carriage is in motion; y, the axle against which the stirrup c¹ abuts at the
moment of the reaction of the main spring.
In Figure 3 one wheel is compressed between two shoes abutting against
each other. a, connecting rod carrying the fore shoe; a¹, connecting rod
carrying the back shoe; b, a frame, moveable both vertically and horizontally;
a stirrup fixed to the frame arrests the fore shoe and the frame in the descent;
c', back stirrup fixed to the frame of the carriage; e, main reaction spring
against which the connecting rod a bears; f, fore shoe; fa, back shoe; g,
return spring of the back stirrup, keeping the connecting rod in contact with
the stirrup during the time the wheel is in' motion; à return spring fixed at
one side to the frame of the carriage and on the other to the pivot of the
moveable.frame, retains the back shoe at a short distance from the wheel
whilst the wheel is in motion.
T.
Figure. 4 represents an arrangement similar to the preceding, only the
frame is fixed and resembles that shewn in Figure 1. (the shoe is shewn
lowered). a, the great connecting rod carrying the fore shoe'; a', the small
connecting rod carrying the back shoe; b; the guide bar fixed upon the grease
box; b', frame, moveable horizontally; c', fore stirrup; e, main reacting spring;
i, sliding box supporting the connecting rod upon the guide bar.
The gear which governs the breaks is so arranged that: all the shoes fall
simultaneously.