IMPROVE- MENTS IN STONE CRUSHERS
Year: 1879

page_text: LETTERS PATENT to Edward Thomas Hughes, of the Firm of Hughes and Son,
Patent Agents, 123, Chancery Lane, London, for the Invention of "IMPROVE-
MENTS IN STONE CRUSHERS." A communication from abroad by the Blake
Crusher Company, of the City and County of New Haven, and State of
Connecticut, United States of America.
Sealed the 12th March 1880, and dated the 16th September 1879.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Hughes at
the Office of the Commissioners of Patents on the 16th September 1879.
EDWARD THOMAS HUGHES, of the Firm of Hughes and Son, Patent Agents, 123,
Chancery Lane, London. "IMPROVEMENTS IN STONE CRUSHERS." A communication
from abroad by the Blake Crusher Company, of the City and County of New Haven,
and State of Connecticut, United States of America.
The object of this Invention is to construct a stone breaking machine in which
the tensile strains due to the performance of its work shall be almost wholly upon
wrought iron or steel, instead of cast iron, giving lightness and strength combined,
and to provide for the adjustment of the opening at the bottom of the jaws and the
length of stroke of the movable jaw, without the substitution of parts, and also to
provide against breakage from undue and excessive strains to which such machines
are likely to be subjected; and the Invention consists in the construction hereinafter
described.
On the accompanying Sheet of Drawings-
Figure 1 is a top or plan view.
Figure 2, a longitudinal section.
A is a three sided framework of cast iron or steel with broad flanged base resting
upon thin elastic cushions a placed between it and the two parallel timbers B, B,
upon which it is supported.
This casting forms the front and two sides of the jaw opening A', and affords a
support for the shaft b on which the swing or moveable jaw A is suspended, and
together with the moveable jaw A² constitute the upright convergent jaws of the well
known "Blake stone breaker."

page_text: Holes in the sides of this casting are left or bored to receive the main tension rods
of the machine E, E, and it is held in position on the parallel timbers by means of
holts or screws passing through the bottom flanges. C, C, are wrought iron or steel
clamps, one on each side of the jaw opening, which serve to take a portion of the
strain due to the crushing of material in the upper portion of the jaws, to hold the
shaft of the moveable jaw in position, and to form a part of the walls of the jaw
opening. These clamps may be closely fitted or bolted on to the cast frame,
or both.
D is a casting of iron or steel forming the back end of the machine or toggle.
block, against which one end of a toggle of the toggle joint hereinafter referred to
abuts, and which is perforated with holes corresponding to those in the front casting,
to receive bolts of wrought iron or steel, forming the main tension rods E, E, above
referred to. This casting D also rests upon elastic cushions a on the parallel timbers
which support the front casting.
The main tension rods E, E, may be either round, square, or flat bars; they
connect the front and rear castings, and are provided with screw thread and nuts, or
with some equivalent arrangement, by means of which the position of the rear part
D with reference to the front part of A' may be adjusted as desired.
The necessary short vibratory motion of the swing jaw is derived from the toggle
or elbow joint between the back of the moveable jaw, suspended in the front part,.
and the rear part, which for convenience may be called the "toggle block."
This toggle joint is worked by means of an eccentric or crank shaft G through the
pitman hereinafter described which connects the toggle joint and main shaft.
The main shaft is held in position and revolves in bearings I bolted on to the
under side of the timbers B, B, on which the front and rear parts of the machine are
cushioned and supported.
The pitman connecting the shaft and the toggle joint consists of a block F in
which the main eccentric or crank shaft works, wrought iron or steel rods, L L,
screwed, cast, or keyed into the said block. The pitman head H, in which are holes
to receive the rods L, L, and which is free to slide up and down on said rods, spiral
springs N, N, on the rods, and the nuts n, n, above the head to hold the head block
in position. The object of the spiral springs is to cause the pitman head to follow
when the nuts are unscrewed; they may be replaced by nuts on the rods, by means
of which the position of the pitman head on the rods may be adjusted as desired.
Oil holes drilled through the length of the pitman rods furnish a convenient means
of oiling the main shaft.
In operation the toggle joint works only on one side of a line, joining the toggle
bearing in the moveable jaw, and the toggle bearing in the main toggle block or
rear part of the machine.
The stroke of the jaw will depend upon the length and inclination of the toggles,
as well as upon the eccentricity of the shaft. If the pitman head be so adjusted as
to bring the toggles into line at the end of the forward stroke of the moveable jaw
the minimum stroke would be employed.
The proportion adopted in making a working stone crushing machine are such
that when the toggles are brought into a straight line the stroke of the jaw would
be hardly appreciable, but if by means of the adjustment of the pitman head on the
rods we give the toggles an inclination of 5° say, at the end of the forward stroke
of the moveable jaw, and then revolve the shaft, the inclination of the toggles to a
line joining the toggle bearing in the moveable jaw and the toggle bearing in the
toggle block will of course increase until the end of the backward motion of the jaw
is attained. We shall then find the length of the toggles and eccentricity of the
shaft remaining the same, that the motion of the moveable jaw, instead of being
hardly appreciable, would be nearly one half an inch, a stroke sufficiently great for
practical work of stone breaking on a large scale. A still greater inclination of the
toggles would give a longer stroke.
To illustrate by an example the increase of stroke of the moveable jaw by the

page_text: increase of inclination of the toggles by means of the adjustment of the pitman head,
let us suppose the eccentricity of the shaft to be five eighths of an inch, the stroke
of the pitman would be one and one quarter inches, suppose the toggles to be of
equal length, and that length fifteen inches.
The stroke of the moveable jaw when the pitman is adjusted so as to bring the
toggles into line at the end of the forward stroke of the jaw would be equal to 'the
sum of the versines of the arcs, through which the ends of the toggles bearing on
the pitman head move. The sine of the are would be equal to the stroke of the
pitman, i.e., 1/4 inches, and the inclination of the toggles at the back end of the
stroke of the jaw would be 4° 47'.
;
The length of stroke of the moveable jaw would be about one tenth of an inch
or practically nothing. If now we set the pitman head so that the toggles when
the end of the forward stroke of the jaw is attained shall be inclined to the line
joining the bearings on the swing jaw and main toggle block at an angle of 4°, 47',
the angle of their inclination to the same line when the end of the backward
stroke of the swing jaw is attained would be measured by an are, whose sine is
two and one half inches, this with a radius of 15 inches would be 9°, 30', and the
length of the stroke would be over three tenths of an inch, a stroke sufficiently
great for the practical work of stone breaking on a large scale. The length of the
swing jaw having been adjusted as desired, the adjustment of the opening at the
bottom of the jaws is made by screwing up or unscrewing the nuts on the main
tension rods at the rear of the machine. It is evident therefore that an adjustable
pitman combined with a toggle joint gives the means of adjusting the length of the
stroke of the moveable jaw within any reasonable working limits without the sub-
stitution of parts.
The main shaft is provided with fly wheels and pulley or other means for com-
municating power to the machine.
The moveable jaw A2 is withdrawn by means of a rubber spring J on a rod K,
which passes through a transverse timber connecting the two parallel timbers on
which the main castings are cushioned, and hooks into an eye in the bottom of the
moveable jaw.
The timbers B, B, and the elastic cushion between them and the body of the
machine or main castings form component parts of the machine. The former may
be regarded as inverted beams in which the front and rear parts or castings form
the points of support, and the strain upon the pitman is the load. They act as
springs; they are calculated to resist all normal strains upon the shaft, but are
intended to yield by their elasticity, and in the case of undue strains by com-
pression of fibres. In case of such compression of the fibres, the machine may be
readjusted by means of the nuts on the pitman, and main tension rods to the jaw
opening and length of stroke it is desirable to employ. The timbers B, B, may be
replaced by an elastic beam or girder of wrought iron. The cushions a, a', between
the body and beams B, B, may be of rubber or other elastic material 1/4 to ³/th
of an inch in thickness.
It is evident that the same result might be obtained by cushioning the main
shaft boxes on the underside of the beams B, B, or by a cushion above the pitman
head block, between the block and a plate on which the pitman rod nuts should
bear. The method of cushioning between the body and supporting timbers or
beams is adopted on account of the convenience and of the larger bearing surface
there obtainable. The bearing surface of the cushions beneath the body or main
castings are so large, and the strain tending to compress them so small per limit of
surface, compared with that on the main tension rods of the machine, that they
will not yield materially under the strain on the pitman, incident to the ordinary
work of stone breaking, but will yield in case of an undue or excessive strain, such
for example as the accidental intrusion of a wedge shaped piece of stone, presenting
an exceptionally large surface or fragments of cast iron, steel, or other metals
offering extraordinary resistance to compression. The result in case of such undue

page_text: strains would be a stoppage of the motion of the swing jaw before reaching the full
limit of its ordinary stroke, combined with a subsequent partial revolution of the
fly wheels before they came to a full stop, thus producing a great diminution of
strains on the parts of the machine compared with those whose parts are so rigid
that the fly wheels must under similar circumstances come almost instantly to a.
stand still, and subject the parts of the machine to sudden and enormous strains
which must necessarily cause breakage.
It is evident that with a pitman of the construction described a greater number
of rods may be used, or a single rod might be substituted for the two shown in the
Drawing.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edward Thomas Hughes in the Great Seal Patent Office on, the
16th March 1880.
EDWARD THOMAS HUGHES, of the Firm of Hughes and Son, Patent Agents,
123, Chancery Lane, London. "IMPROVEMENTS IN STONE CRUSHERS." A commu-
nication from abroad by the Blake Crusher Company, of the City and County of
New Haven, and State of Connecticut, United States of America.
The object of my Invention is to construct a stone breaking machine in which
the tensile strains due to the performance of its work shall be almost wholly
upon wrought iron or steel instead of cast iron, giving lightness and strength
combined, and to provide for the adjustment of the opening at the bottom of the
jaws, and the length of stroke of the moveable jaw without the substitution of
parts, and also to provide against breakage from undue and excessive strains to
which such machines are likely to be subjected.
The Invention consists in the construction hereinafter described and particularly
recited in the claims on the accompanying Sheet of Drawings.
Fig. 1 represents a plan or top view.
Fig. 2 represents a longitudinal section of the machine as I have con-
structed it.
Figs. 3, 4, and 5, modifications.
A is a three sided framework of cast iron or steel with broad flanged base
resting upon thin elastic cushions a placed between it and the two parallel timbers
B, B, upon which it is supported.
This casting forins the front and two sides of the jaw opening A¹, and affords a
support for the shaft b on which the swing or moveable jaw A² is suspended, and
together with the moveable jaw A2 constitute the upright convergent jaws of the
well known "Blake Stone Breaker." Holes in the sides of this casting are left or
bored to receive the main tension rods of the machine E, E, and it is held in
position on the parallel timbers by means of bolts or screws passing through the
bottom flanges; C, C, are wrought iron or steel clamps, one on each side of the jaw
opening, which serves to take a portion of the strain due to the crushing of material
in the upper portion of the jaws to hold the shaft of the moveable jaw in position,
and to form a part of the walls of the jaw opening. These clamps may be closely
fitted or bolted onto the cast frame or both; D is a casting of iron or steel forming
the back end of the machine or toggle block against which one end of a toggle of
the toggle joint hereinafter referred to abuts, and which is perforated with holes
corresponding to those in the front casting to receive bolts of wrought iron or steel
forming the main tension rods E, E, above referred to. This casting D also rests
upon elastic cushions a on the parallel timbers which support the front casting.
The main' tension rods E, E, may be either round, square, or flat bars. They connect
the front and rear castings and are provided with screw thread and nuts, or with
some equivalent arrangement by means of which the position of the rear part D
with reference to the front part A¹ may be adjusted as desired. The necessary short
vibratory motion of the swing jaw is derived from the toggle or elbow joint
between the back of the moveable jaw suspended in the front part, and the rear
part which for convenience may be called the "toggle block."
This toggle joint is worked by means of an eccentric or crank shaft G through
the pitman hereinafter described, which connects toggle joint and main shaft. The
main shaft is held in position and revolves in bearings I bolted on to the under.
side of the timbers B, B, on which the front and rear parts of the machine are
cushioned and supported..
The pitman connecting the shaft and the toggle joint consists of a block F in.
which the main eccentric or crank shaft works, wrought iron or steel rods L, L,

page_text: screwed, cast, or keyed into the said block. The pitman head H in which are holes
to receive the rods L, L, and which is free to slide up and down on said rods, spiral
springs N, N, on the rods, and the nuts n, n, above the head to hold the head block
in position. The object of the spiral springs is to cause the pitman head to follow
when the nuts are unscrewed; they may be replaced by nuts on the rods by means of
which the position of the pitman head on the rods may be adjusted as desired.
Oil holes drilled through the length of the pitman rods furnish a convenient means
of oiling the main shaft. In operation the toggle joint works only on one side of a
line joining the toggle bearing in the main toggle block or rear part of the machine.
The stroke of the jaw will depend upon the length and inclination of the toggles
as well as upon the eccentricity of the shaft. If the pitman head be so adjusted as
to bring the toggles into line at the end of the forward stroke of the moveable jaw,
the minimum stroke would be employed. The proportion adopted in making a
working stone crushing machine are such that when the toggles are brought into a
straight line the stroke of the jaw would be hardly appreciable, but if by means of
the adjustment of the pitman head on the rods we give the toggles an inclination
of 5°, say at the end of the forward stroke of the moveable jaw, and then revolve
the shaft the inclination of the toggles to a line joining the toggle bearing in the
moveable jaw, and the toggle bearing in the toggle block will of course increase
until the end of the backward motion of the jaw is attained, we shall then-
find the length of the toggles and eccentricity of the shaft remaining the same.
That the motion of the moveable jaw instead of being hardly appreciable would be
nearly one half an inch, a stroke sufficiently great for practical work of stone
breaking on a large scale. A still greater inclination of the toggles would give a
longer stroke. To illustrate by an example the increase of stroke of the moveable
jaw by the increase of inclination of the toggles by means of the adjustment of the
pitman head, let us suppose the eccentricity of the shaft to be five eights of an
inch, the stroke of the pitman would be one and one quarter inches, suppose the
toggles to be of equal length, and that length fifteen inches. The stroke of the
moveable jaw when the pitman head is adjusted so as to bring the toggles into line
at the end of the forward stroke of the jaw would be equal to the sum of the versines
of the ares through which the ends of the toggles bearing on the pitman head nove.
The sine of the are would be equal to the stroke of the pitman, i.e., 1 ½ inches, and
the inclination of the toggles at the back end of the stroke of the jaw would be 4° 47'.
The length of stroke of the moveable jaw would be about one tenth of an inch,
or practically nothing. If now we set the pitman head so that the toggles, when
the end of the forward stroke of the jaw is attained, shall be inclined to the line
joining the bearings on the swing jaw and main toggle block at an angle of 4° 47',
the angle of their inclination to the same line when the end of the backward stroke
of the swing jaw is attained, would be measured by an arc whose sine is two and
one half inches; this with a radius of 15 inches would be 9°, 36', and the length of
the stroke would be over three tenths of an inch, a stroke sufficiently great for the
practical work of stone breaking on a large scale. The length of stroke of the
swing jaw having been adjusted as desired, the adjustment of the opening at the
bottom of the jaws is made by screwing up or unscrewing the nuts on the main
tension rods at the rear of the machine. It is evident therefore that an adjustable
pitman combined with a toggle joint gives the means of adjusting the length of the
stroke of the moveable jaw within any reasonable working limits without the
substitution of parts. The main shaft is provided with fly wheels and pulley or
other means for communicating power to the machine. The moveable jaw A² is
withdrawn by means of a rubber spring J on a rod K, which passes through a
transverse timber connecting the two parallel timbers on which the main castings
are cushioned, and hooks into an eye in the bottom of the moveable jaw. The
timbers B, B, and the elastic cushions between them and the body of the machine
or main castings forin compound parts of the machine. The former may be
regarded as inverted beams, in which the front and rear parts or castings form the

page_text: points of support and the strain upon the pitman is the load; they act as springs.
They are calculated to resist all normal strains upon the shaft, but are intended to
yield by their elasticity, and in the case of undue strains by compression of fibres.
In case of such compression of the fibres the machine may be readjusted by means
of the nuts on the pitman and main tension rods to the jaw opening and length of
stroke it is desirable to employ. The timbers may be replaced by an elastic beam
or girder of wrought iron. The cushions a, a, between the body and beams B, B,
may be of rubber or other elastic material 1/4 to 3/8 of an inch in thickness.
It is evident that the same result might be obtained by cushioning the main
shaft boxes on the under side of the beams B, B, or by a cushion above the pitman
head block, between the block and a plate on which the pitman rod nuts should
bear. I have adopted the method of cushioning between the body and supporting
timbers or beams on account of its convenience, and of the larger bearing surface
there obtainable. The bearing surfaces of the cushions beneath the body or main
castings are so large, and the strain tending to compress them so small, per limit of
surface compared with that on the main tension. rods of the machine, that they will
not yield materially under the strains on the pitman incident to the ordinary work
of stone breaking, but will yield in case of an undue or excessive strain such for
exemple, as the accidental intrusion of a wedge shaped piece of stone presenting an
exceptionally large surface, or fragments of cast iron, steel, or other metals, offering
extraordinary resistance to compression. The result in case of such undue strains
would be a stoppage of the motion of the swing jaw befor reaching the full limit of
its ordinary stroke combined with a subsequent partial revolution of the fly wheels
before they came to a full stop, thus producing a great diminution of strains on the
parts of the machine compared with those whose parts are so rigid that the fly
wheels must under similar circumstances come almost instantly to a stand still,
and subject the parts of the machine to sudden and enormous strains which must
necessarily cause, breakage. It is evident that with a pitman of the construction
described a greater number of rods may be used, or a single rod might be substituted
for the two shown in the Drawing. As thus far described the toggle is not sup-
ported against the twisting strain produced by the working of the machine; such
support would not be required if the toggles on opposite sides of the toggle bearing
can have the same or equal inclination to the toggle bearing, but in practise I find
that it is difficult to attain such a perfect bearing between the two toggles, and that
owing to the vibratory movement given to the pitman by the eccentric on the main
shaft the pressure on one side of the toggle bearing is not exactly counterbalanced
by the pressure of the other, as the inclination of one must be slightly greater than
that of the other, and as a result the tendency is to twist the toggle bearing, and
consequently bend the pitman rod, that is, to turn up that side in which the toggle
bearing is highest, and down the opposite side, so that a greater transverse strain
is brought upon the rod, tending to break it, and it constantly increases as the
bearing wears in the use of the machine. To overcome this difficulty is the object
of this part of my Invention. In the illustration two rods A2, A2, are shown,
combined in a single head B2, in which the eccentric is arranged to operate. C2 is
the toggle bearing, D2, D2, representing the two toggles resting on the bearing at
each side. The bearing C is constructed with a sleeve E2 extending therefrom
onto the rod, as seen in Fig. 5, and so as to take a bearing upon the rod above
the toggle bearing. This sleeve prevents the twisting or turning of the toggle
bearing before described, retains the toggles in their proper line, and thereby relieves
the rod from the transverse strain which is brought upon it by the twisting before
mentioned. Where two or more rods are used, as shown, it is advisable that the
bearing should be provided with a sleeve for each rod; yet a single sleeve may
serve the purpose of preventing twisting or turning of the toggle bearing. Adjust-
ment here shown is made by means of a nut a on the rod below the bearing, and.
a spring b above the sleeve by substantially the same method of adjustment as that
before mentioned, but other methods of adjustment may be applied, and other
arrangement of the rod may be adopted. .

page_text: Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that what is claimed as the Invention is,-.
1. In a stone breaking machine the combination of a pair of upright convergent
jaws, mechanism for imparting a reciprocating or vibratory movement to one of
said jaws, and an elastic or yielding material between said jaws and the point where
the power takes its bearing, substantially as described.
2. The combination in a pitman of the block and head with rod or rods con-
necting said head and block, and nuts and springs to adjust the length of the pitman,
substantially as described.
3. The combination in a stone breaking machine of an adjustable pitman and
adjustable toggle block, substantially as described.
4. The combination in a stone breaking machine with upright convergent jaws
of the front and rear parts, tension bars or rods, and toggle joint, substantially as
described.
5. In a stone breaking machine with upright convergent jaws the clamps C, C,
longitudinally embracing that part of the frame where the jaws are arranged, sub-
stantially as described.
6. The combination in a stone breaking machine of a pair of upright convergent
jaws, one of which has a reciprocating motion with respect to the other, a toggle
bearing upon said jaw, and an adjustable pitman, through which and said toggle
the power is communicated to said jaw, and the movement of said jaw adjusted or
varied as may be desired.
7. In a stone breaking machine a pitman having a toggle bearing adjustable
thereon, said bearing constructed with a sleeve extending from said bearing onto
the pitman rod, substantially as and for the purpose described. .
In witness whereof, I, the said Edward Thomas Hughes, have hereunto set
my hand and seal, this Fifteenth day of March, in the year of our Lord One
thousand eight hundred and eighty.