IM- PROVEMENTS IN MACHINES FOR BREAKING STONE AND CRUSHING ORE
Year: 1876

page_text: LETTERS PATENT to Robert Broadbent and Henry Broadbent, both of Staly-
bridge, in the County of Chester, Machine Makers, for the Invention of "IM-
PROVEMENTS IN MACHINES FOR BREAKING STONE AND CRUSHING ORE."
Scaled the 9th June 1876, and dated the 6th April 1876.
Scaled the 9th June 1876, and dated the 6th April 1876.
PROVISIONAL SPECIFICATION left by the said Robert Broadbent and Henry
Broadbent at the Oflice of the Commissioners of Patents on the 6th April
1876.
ROBERT BROADBENT and HENRY BROADBENT, both of Stalybridge, in the County
of Chester, Machine Makers. IMPROVEMENTS IN MACHINES FOR BREAKING STONE
AND CRUSHING ORE"
"
Our Invention is applicable to those machines in which a fixed and a movable
jaw are employed, and it consists in an improved arrangement of parts for drawing
back the movable jaw after it has been forced towards the fixed jaw by the ordinary
rocking lever or "pitman" and toggles, or other convenient mechanism.
In machines of the usual construction the movable jaw is drawn back by the
expansion of a spring, which is compressed at every stroke of the jaw. Now our
Invention consists in drawing the jaw back by the rocking lever or "pitman," at
the lower end of which is a toggle acting on the horizontal arm of an elbow lever,
the vertical arm of which is connected to the movable jaw by a link with a regu-
lating screw. By this means the power required for compressing the spring
heretofore used is dispensed with.
Our Invention may be modified by the use of a bent lever instead of the elbow
lever above referred to, and by connecting the link to the angle of the said bent
lever; or the levers may be dispensed with, and the lower end of the toggle inay be
jointed to the connecting pin of two links, one of which is hinged to the movable
jaw, and the other to a swivel fulcrum stud; or two links may be suspended to the
rocking lever or pitman, and these links connected to horizontal links jointed to the
jaw and to a swivel fulcrum stud.
The above details may be varied, and the movable jaw can be drawn back by a
cam or eccentric on the driving shaft.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said Robert Broadbent and Henry Broadbent in the Great Seal Patent
Office on the 21st September 1870.
ROBERT BROADBENT and HENRY BROADBENT, both of Stalybridge, in the County
of Chester, Machine Makers. "IMPROVEMENTS IN MACHINES FOR BREAKING STONE
AND CRUSHING ORE."
Our Invention is applicable to those machines in which a fixed and a movable
jaw are employed, and it consists in certain improved arrangements of parts for
drawing back the movable jaw after it has been forced towards the fixed jaw by the
ordinary rocking lever or "pitman" and toggles, or other convenient mechanism.
In machines of the usual construction the movable jaw is drawn back by the
expansion of a spring, which is compressed at every stroke of the jaw, and this com-
pression of the spring is a waste of power; but by means of our Invention the power
required for compressing the spring is dispensed with.
And in order that our Invention may be fully understood and readily carried into
operation, we will proceed to describe the accompanying Sheet of Drawings,
reference being had to the figures and letters marked thereon.
Fig. 1 is a sectional elevation of a machine for breaking stone and crushing ore
constructed according to our improvements. a is the ordinary rocking lever or
'pitman," which is caused to vibrate by an eccentric on the driving shaft b; c, c, are
the toggles, forming on one side the communication between the lower end of the
"pitman" and the toggle block d, and on the other side with the movable jaw e,
which is thus made to approach the fixed jaw f. All these parts and the framing
for supporting them are made in the usual manner. At the lower end of the "pit-
man is the toggle g, which acts on the horizontal arm of the elbow lever h, the
vertical arm of which is connected to the lower end of the movable jaw e by the
link i, one end of which is screwed, and is provided with a regulating nut j. By
this arrangement when the driving shaft 6 revolves the toggle g causes the elbow
lever h to vibrate, and at every revolution the movable jaw e, which had been
moved forward by the toggles c, is brought back by the lever hand link i, thereby
economising the power heretofore exerted to compress the spring by which the
movable jaw was brought back.
Fig. 2 represents a modification of our Invention. In this case the lower end of
the toggle g is jointed to the connecting pin of the two links k and l, the former
being hinged to the movable jaw e, and the latter after passing through a slot in the
framing is provided with a swivel fulcrum stud and regulating lock nuts.
Fig. 3 represents part of a crushing machine to which another modification of our
Invention is applied. In this case the lower end of the toggle g acts upon the bent
lever m, through which is a slot for the connecting link to pass through; this link
is connected to the movable jaw e, and it is provided with a regulating screw nut j,
as in Fig. 1.
Fig. 4 represents a crushing machine of the usual construction, in which the
rocking lever or "pitman" a is mounted on a fulcrum stud b', to which another
modification of our Invention is applied. In this instance the two links g,
suspended to the rocking lever or "pitman" a, are connected by the horizontal
link n, one end of which is connected by the link k to the lower end of the movable
jaw e, and the other by the link to the swivel fulcrum stud resting in a recess in
the framing.
Fig. 5 represents another modification of our Invention. In this case the movable
jaw e is drawn back by the double cam o on the crank shaft b; the cam acts on
the upper end of the lever o¹, the lower end of which is connected to the movable
jaw by the link k, which is provided with a swivel fulcrum stud and a regulating
screw nut
Fig. 6 represents part of a crushing machine constructed according to another
modification of our Invention. In this case the elbow lever his similar to that

page_text: shewn in Fig. 1, and the requisite vibrating motion is imparted to it to draw back
the movable jaw e by the vertical rod p acting on the elbow lever h. The vertical
rod p is suspended to the eccentric by which the rocking lever or "pitman" a is
worked.
Having thus stated the nature of our Invention, and described several convenient
modes of performning the same, we wish to remark that we do not intend to limit
ourselves to the details given, as the same may be considerably varied or modified;
and that what we claim is, drawing the movable jaw of a crushing machine back by
the rocking lever or "pitinan," or by any other working part of the machine, instead
of by the compression of a spring, as heretofore customary.
In witness whereof, we, the said Robert Broadbent and Henry Broadbent,
have hereto set our hands and seals, this Sixteenth day of September, One
thousand eight hundred and seventy-six.
Signed, sealed, and delivered by the
above-named Robert Broadbent and
Henry Broadbent in the presence of
LEONARD BROADBENT,
The Hollins,
Stalybridge.
(L.S.)
ROBT. BROADBENT.
HENRY BROADBENT. (L.S.)