IMPROVEMENTS IN MACHINERY OR APPARATUS FOR CRUSHING, BREAKING, AND PULVERIZING HARD AND BRITTLE SUBSTANCES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by George Dalton at the Office of the
Commissioners of Patents on the 23rd February 1876. A communication
from Henry Rowland Marsden, of Leeds, in the County of York.
GEORGE DALTON, of Leeds, in the County of York. "IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR CRUSHING, BREAKING, AND PULVERIZING HARD
AND BRITTLE SUBSTANCES." A communication from Henry Rowland Marsden,
of Leeds aforesaid.
This Invention relates first to that description of apparatus in which the stones
or other hard and brittle substances to be broken or reduced are operated upon
between a stationary jaw and a moveable jaw, or between two moveable jaws, and
which apparatus are generally known as Blake's stone breaking machines, and it has
for its object reducing the stones (for example) to a form approximating more nearly
to that of a perfect cube than is attainable with the apparatus as heretoforc
constructed.
In carrying out this part of the the Invention as applied (for example) to a machine
having a moveable jaw and a stationary jaw, the moveable jaw is constructed in
the following manner:-The face is provided with teeth or corrugations of any suitable
shape and pitch, and extending straight from the top to any required distance below
which the teeth or corrugations which may be either of the same or smaller pitch,
as the upper ones are diverted laterally as has previously been proposed; but
according to the present Invention in lieu of making the front face of the teeth a
continuous contour from the top of the jaw to the bottom thereof, the lower or diverted
teeth recede, that is to say, the teeth are so arranged that the face of the upper teeth
projects to some extent beyond the face of the lower or diverted teeth. The
stationary jaw is provided with upper teeth and lower diverted teeth in a similar
manner, but the teeth are arranged by preference so that the face of the teeth is
straight or forms a continuous contour from the top to the bottom; or the stationary
jaw may be made of a counterpart form to the moveable jaw or otherwise, the object
being to cause the stone under operation after it has been first broken by the upper
teeth on reaching the top of the lower or diverted teeth to roll or turn over by
reason of the sudden change or recession in the plane of the face of the teeth from
the upper and lower sets of the teeth of the moveable jaw projecting the one
beyond the other, whereby the stones are reduced to a more perfect cuboidal form
in lieu of to a semi-clongated form as is frequently the case when operated upon

page_text: in the apparatus as previously constructed. It is obvious that the converse of this
arrangement may be adopted, the stationary jaw being made of the shape herein-
before described with reference to the moveable jaw, and vice versa.
It is proposed to make the working faces of the jaws renewable and also rever-
sible from top to bottom and back to front, also to make the face in two parts,
the one carrying the upper teeth and the other the lower teeth, and to secure
the two parts together at their meeting point by means of a wedge extending
throughout the width of the jaw and by bolts and nuts, the jaw stock or frame being
made of a suitably dovetail recessed form for their reception. A flat surface level
with the point of the teeth may be formed transversely on a portion of the jaw face,
the teeth merging thereinto either from above or below, or both above and below, as
required.
The Invention relates, secondly, to machinery for crushing or reducing stones and
other hard and brittle substances to a fine state of division, and it consists in the
employment of two discs the one rotating and the other stationary, between which
the substances under treatinent are to be operated upon. The discs are provided
with teeth or projections arranged by preference in radial sets either all of the
same dimensions or otherwise over the whole or any required portion of the face
of the discs and which form the acting or reducing surfaces. The rotating disc is
mounted in a suitable frame or casing on a shaft or axis, by preference arranged
horizontally and provided with driving pulleys and gear so as to enable the disc to
be driven alternately in opposite directions in order to equalize the wear of the
teeth. The stationary disc is fitted in the frame in such a manner as to admit of
its position relatively to the rotating disc being adjusted to suit the degree of
division to which the substances are to be reduced. One or both of the discs is or
are made slightly dished or concave for the reception of the substances to be operated
upon, and which are fed thereinto from a hopper through an aperture in the centre
of the stationary disc. The teeth of the disc are made of hard or chilled cast iron,
by preparing a metal plate or mould to the shape of the counterpart of the disc
with its teeth to be produced, and first pouring in white iron in a molten condition
to a sufficient height to form the teeth, and then filling the mould with hematite or
other suitable iron in one continuous operation, whereby great durability of the
wearing surfaces of the disc is obtained.
It is obvious that the jaw faces of the apparatus first herein-before described may
be cast in a similar manner if desired.