IMPROVEMENTS IN BRAKE SHOES, FOR BRAKING RAILWAY CARS
Year: 1884

page_text: COMPLETE SPECIFICATION.
I, JOHN JOSEPH LAPPIN, of the City of Toronto, in the County of York, in the
Province of Ontario, in the Dominion of Canada, Gentleman, do hereby declare
the nature of my invention for IMPROVEMENTS IN BRAKE SHOES, FOR BRAKING
RAILWAY CARS, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:
My invention has for its object the construction of a brake shoe, which will have
greater durability than the brake shoes now in use, and is constructed without the
imbedding of pieces of other metal in the face of the shoe, which has been done by
others in order to obtain greater durability in the wear of the shoe.
My invention is an improvement on the brake shoes now in use, both from its
greater durability, and from its not skidding the wheels when braking the train.
My invention consists in the hardening by means of chills in the process of
casting certain parts of the face of the shoe, and leaving other parts of the face
"soft" and so proportioned as to produce an effective brake shoe, and durable; and
to operate effectively in stopping the trains without skidding the wheels, as.
hereinafter more fully described.
In the accompanying drawings, Figure 1 is an edge view of my brake shoe.
Figure 2 is an end view of the same. Figure 3 is an edge view of the pattern
and chills. Figure 4 is a transverse sectional view through the line a, b, in
figure 3, showing the chill as it is placed on the pattern previous to being covered
up in the sand. Figure 5 is a perspective view of the face and edge of the shoe.
Figure 6 is a side view of chill.
Similar letters represent similar parts, in all the views and in this specification.
A, represents the shoe; B, the face thereof; C, the chilled parts of the face, and
the supposed average depth of the same; D, the unchilled parts; E, the pattern
from which the shoe is moulded in the sand; c, the chills; c¹, the projections which
embrace the edges of the pattern.
Referring to Figure 1 it will be observed that the chilled parts, c, in the face of
the shoe are about of equal surface to the unchilled parts, D, but this proportion
may be varied as circumstances may require. Referring to Figure 3 it will be
found that the.chills, c, are laid into recesses in the face of the pattern, E, securing
the said chills sidewise therein, so that they will not shift, due care being taken in
the ramming of the sand around and between the pattern and the chills. Referring

page_text: to Figure 4 it will be observed that the chills are prevented from moving edgewise,
in the ramming previously referred to, by the projections, c¹, passing up each edge
of the pattern so that in ramming the sand, and withdrawing the pattern from the
mould and the pouring of the molten iron therein, the chills will remain in their
position, and will be attached to the shoe after it is cast, but will fall off in the
dressing, and leave the shoe ready for attachment to the brake and for use.
In the process of casting my brake shoe in the foundry from the molten pig
iron, I place in the pattern E, when laying in the sand prior to making the mould,
certain pieces of metal, suitably prepared for my purpose and place the same in
recesses prepared in the face of the pattern, which pieces having projections c' on
each side and made to embrace the edges of the pattern E, by which means, when
the sand is carefully rammed between and around the pieces, c, and also around
the pattern E, the latter is removed without disturbing the pieces of metal
aforesaid, which remain in the mould, and when the molten metal is poured
therein, they act as chills and harden certain portions of the face of the shoe viz :
those portions with which they come in immediate contact, and produce a new
character in the metal, which is well adapted for brake shoes. The durability is
greatly increased and they do not skid the wheels.
Returning to Figure 1 of the drawings, it will be observed that the soft portions
in the face of the shoe project out from the chilled portions; one of the objects
sought to be obtained by such projections, being, that the soft portions will wear
sooner and bring the shoe to a full and exact bearing on the rim of the wheel
before the chilled portions come in contact with the wheel, and prevent the shoe
from being broken as it would be, when not fitting the wheel. In specifying the
proportions of the chilled and unchilled parts in the face of my shoe, I do not limit
my claim in its entirety, to such proportions but shall claim whatever else it may
transpire that I am entitled to under the foregoing description and drawings
forming parts of the same.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:
A brake shoe, with chilled portions, C, in the face thereof, and soft projecting
portions, D, between the chilled portions; which soft portions will wear and bring
the shoe to an exact bed on the rim of the wheel before the chilled portions come
in contact therewith, and thereby protecting the shoe, substantially as described as
a new manufacture.
F