Improvements in Brakes for use on Railways.
Year: 1891

page_text: Date of Application, 19th Mar., 1891-Accepted, 2nd May, 1891
COMPLETE SPECIFICATION.
Improvements in Brakes for use on Railways.
A communication from THOMAS MILBURN, of 55, Colborne Street, in the City of
Toronto, in the County of York, in the Province of Ontario, Canada,
Merchant.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., do hereby declare the nature of this invention 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 the invention is to produce a detachable shoe for a railway carriage
brake, which will present the necessary frictional resisting surface to act success-
fully as a brake, with a minimum of wear upon the tyre or tread of the wheel; and
it consists essentially of a brake shoe cast in one piece, and having its wheel
engaging surface formed of alternating soft and chilled portions integral with the
body of the shoe, substantially as hereinafter more particularly explained.
Figure 1 is a perspective view of this improved brake shoe.
Figure 2 is a plan of the same.
Figure 3 is a perspective view of a brake head to receive the improved shoe.
Figure 4 is a perspective back view of the improved shoe designed to connect
with the brake head shown in Figure 3.
Figure 5 is a view of the key employed to connect the brake shoe to the
brake head.
Figure 6 is a perspective view showing the improved shoe connected to the
brake head.
Figure 7 is a perspective face view of the improved brake shoe designed to act
against the driving wheel of a locomotive.
Like letters of reference indicate corresponding parts in each figure.
In the drawing A represents the improved brake shoe, the wearing surface of
which is composed of alternately soft and chilled portions, the soft portions a pro
jecting slightly above the surface of the hard portions b. These soft projecting
portions a correspond with the character of the metal forming the major portion
of the shoe A while the hard portions are hardened by the action of a chill
forming a portion of the mould in which the shoe is cast, both hard and soft
portions being integral with the body of the shoe and mix with each other so
closely that no clearly defined dividing line is left to form a cutting edge. When
the shoe is applied to the tyre or tread of the wheel the soft projecting portions a
are soon worn to the level of the chilled or hardened portions below which they
will practically cease to wear, as the hardened or chilled portions successfully
resist the action of the friction, and in this way I secure a brake shoe which will
not only present the necessary frictional resisting surface, but will also last for an
indefinite period, and cannot be applied with such force as to skid the wheels, or cut
or in any other way act injuriously upon the tread or tyre of the wheel.
My correspondent does not wish to confine himself to the exact design shown for
the arrangement of the soft and hard surfaces of the improved shoe, as the said
hard surface may be brought closer to or removed further from each other, and
may be arranged in any design desired.
Nor does he wish to confine himself to the use of any particular brake head, but
for the purpose of this Specification, I illustrate a brake head which is adapted to
receive the improved brake shoe.
In the drawings B represents the brake head, the face of which has two pro-
jections C between which a projection D formed on the back of the shoe A fits.
Keyways d are made in the projections C and D to receive the key E which also

page_text: By this
passes through the grooves e made in the face of the brake head B and rests upon
the surface of the rib f made on the back of the shoe A as indicated.
arrangement a secure connection is formed between the brake shoe A and brake
head B which permits the shoe A to be readily detached when necessary..
In Figure 7 a shoe adapted to act upon the tyre of a locomotive driving wheel
is exhibited. This form of brake shoe is the same as shown in the other illustrations
except that it is made to fit over the flange of the wheel.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent, and in what manner the
same is to be performed, I declare that what I claim is :-
1. A brake shoe cast in one piece, having its wheel engaging surface formed of
alternating soft and chilled portions integral with the body of the shoe.
2. A brake shoe cast in one piece, having its wheel engaging surface formed of
alternating soft and chilled portions integral with the body of the shoe, with the
soft portions, a projecting slightly past the chilled portions b.
Dated this 16th day of March 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.