Improvements in or applicable to Stamp-batteries.
Year: 1893

page_text: Date of Application, 21st Apr., 1893
Complete Specification Left, 22nd Jan., 1894-Accepted, 24th Feb., 1894
PROVISIONAL SPECIFICATION.
Improvements in or applicable to Stamp-batteries.
I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the
City of London, Civil Engineer and Chartered Patent Agent, do hereby declare
the nature of this invention (a communication to me from Charles Raleigh, of
Johannesburg, in the South African Republic, Milling Engineer,) to be as
follows:-
1
This invention relates to the tappets and cams employed in stamp-batteries and
crushing mills for lifting and dropping the stem-rods to which the stamps are
attached.
It is usual to make the under surface of the tappet flat; such surface lying in a
horizontal plane, that is, in a plane at right angles to that in which the axis of the
stem lies.
According to the present invention, the under surface of the tappet is dished or
hollowed out; the hearing or lifting surface of the cam being inclined or shaped to
correspond. When the tappet and cam are so made, wear on the guide-blocks is
diminished.
The lower part of the tappet may, however, be bevelled or rounded; the bearing
surface of the cam being of corresponding form. A stem furnished with a tappet
bevelled or rounded as described, when acted upon by two cams, one on each side,
tends to centre itself between the cams. *
Ordinary tappets have a narrow flange at the top and bottom. I add a third
flange between the other two, a series of radial holes being made in the latter. Or,
the top or the bottom flange may be widened, and the holes made therein. The
holes are intended to receive the end of a lever or bar, by means of which the
stem can be turned in order to bring the keys into an accessible position.
Instead of making the arm of the cam solid as hitherto, I leave a hole in the
same, which, besides lightening the cam, enables a drift or bar to be inserted for
getting at the keys of other cams on the same shaft; whereas, with solid arms, if a
central cam get loose, it is necessary to unkey the outer cams before the loose one
can be tightened.
Dated the 20th day of April 1893.
COMPLETE SPECIFICATION.
Improvements in or applicable to Stamp-batteries.
I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the
City of London, Civil Engineer and Chartered Patent Agent, do hereby declare
the nature of this invention (a communication to me from Charles Raleigh, of
Johannesburg, in the South African Republic, Milling Engineer,) and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :- .
This invention relates to the tappets and cams employed in stamp-batteries and
crushing mills for lifting and dropping the stem-rods to which the stamps are
attached.
In the accompanying drawings,
Fig. 1 is a front elevation of the upper part of a stamp-battery furnished with
tannets made in accordance with the present invention.

page_text: Fig. 2 is a detail view drawn to a larger scale showing one of the tappets in side
elevation.
Fig. 3 is a vertical section on the line x, x.
Figs. 4 to 6 illustrate modified forms of tappet.
Fig. 7 is a cross section on the line y, y.
Figs. 8 and 9 represent tappets of different design.
Fig. 10 is a side elevation of the improved cam.
It is usual to make the under surface of the tappet flat; such surface lying in a
horizontal plane, that is, in a plane at right angles to that in which the axis of the
stem lies.
According to the present invention, the under surface A or A¹ of the tappet is
dished or hollowed out; the bearing or lifting surface B or B₁ of the cam being
inclined or shaped to correspond. When the tappet and cam are so made, wear on
the guide-blocks is diminished.
The lower part A² or A³ of the tappet may, however, be bevelled or rounded;
the bearing surface B2 or B³ of the cam being of corresponding form. A stem
furnished with a tappet bevelled or rounded as described, when acted upon by two
cams, one on each side, tends to centre itself between the cams.
Ordinary tappets have a narrow flange at the top and bottom. I add a third
flange A between the other two, a series of radial holes A' being made in the
latter. Or, the top or the bottom flange may be widened, and the holes made
therein, as shown in Figs. 8 and 9. The holes are intended to receive the end of a
lever or bar C, by means of which the stem can be turned in order to bring the
keys or other parts into an accessible position.
Instead of making the arm of the cam solid as hitherto, I leave a hole D in the
same, which, besides lightening the cam Dx, enables a drift or bar to be inserted
for getting at the keys of other cams on the same shaft; whereas, with solid arms,
if a central cam get loose, it is necessary to unkey the outer cams before the loose
one can be tightened.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim :-
1. In a stamp-battery or crushing mill, the employment of a tappet having its
under surface dished or hollowed out, and a cam having its bearing or lifting
surface inclined or shaped to correspond, substantially as herein described.
2. In a stamp-battery or crushing mill, the employment of a tappet having its
lower part bevelled or rounded, and a cam having its bearing surface of corre-
sponding form, substantially as herein described.
3. In a stamp-battery or crushing mill, the employment of a tappet containing a
series of radial holes, whereby the stem can, by means of a lever inserted into one
or successively into more than one of the holes in the tappet, be turned into any
desired position, substantially as herein described.
4. In a stamp-battery or crushing mill, the employment of cams having holes in
their arms, the holes serving to enable the key of a loose intermediate cam to be
got at without unkeying the outer cam or cams, substantially as herein described.
Dated the 20th day of January 1894.
G. G. M. HARDINGHAM.