Improvements in Stamp Mills and Amalgamators.
Year: 1893

page_text: Date of Application, 14th Nov., 1893-Accepted, 16th Dec., 1893
COMPLETE SPECIFICATION.
Improvements in Stamp Mills and Amalgamators.
We, CHARLES CARTER, and ALfred Henry BELL, both Mining Engineers,
residing at Ibapah, in the County of Tooele, Utah, one of the Territories of the
United States of America, do hereby declare the nature of this invention 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 stamp mills and amalgamators which are more
particularly adapted for gold ore; and it consists in the novel construction and
combination of the parts hereinafter fully described and claimed.
In the accompanying drawings:
Figure 1 is a side view of the machine showing the mortar box and tank in
section.
Figure 2 is a cross section through the mortar box and tank.
Figure 3 is a plan view of the mercury boxes removed from the mortar box.
Figures 4 and 5 are two side views showing two modifications of the device for
operating the stamp.
A is the mortar box provided with a die a at each end, and having a space a¹
between the two dies.
B is the stamp provided with a shoe bat each end. The shoes have convex
surfaces which bear on the dies a.
B¹ is a horizontal arm at the top of the stamp for operating it; and b¹ is also a
horizontal arm which engages with the vertical guide A' and keeps the stamp from
twisting around.
The end c of the arm B' is forked, and is provided with a series of boles c¹. C is
the driving shaft which is driven by the pulley C¹ or any other approved driving
device.
D is a crank on the shaft C, and d is a pitman connected to the crank, and
provided with a piu d' for connecting its upper end with either of the holes c¹. A
series of holes is provided so that the connection of the pitman may be changed to
compensate for the wear of the stamp shoes and dies.
The pitman d has a guide shoe e pivoted to it which works on the vertical
guide E which is suitably secured and braced to the base of the machine. Two
similar guides may be used, one on each side of the pitman.
When motion is imparted to the crank in the direction of the arrow in Figure 1,
the stamp shoes are raised alternately. The shoe in contact with one of the dies is
pushed along the die towards the space between the dies while the other shoe is
being raised and lowered, and the descending shoe comes down upon the outer end
of its die and is adapted to be moved across its face when the other shoe is being
lifted and lowered.
Figure 4 shows a modified form of the pitman in which the arm of the stamp is
pivoted to the pitman between the crank and the guide shoe.
In Figure 5 the guide is inclined and the piston rod of a motor cylinder is
connected to the guide shoe.
In each case the stamp has a longitudinally reciprocating motion imparted to it,
and the stamp shoes are raised and lowered alternately.
F is a bent plate having its surface covered with copper amalgamated with
mercury. This plate is bent across its center and has its ends inclined in opposite
directions like the sides of a wedge or cone, the apex being at about the middle of
the mortar box. Two mercury boxes f are arranged at the lower ends of the
plate F, and these boxes and plate are supported on packing pieces in the space a¹
so that the top edges of the mercury boxes come level with the tops of the dies.
ID 21

page_text: The mercury boxes are lowered in the space a' as the dies wear away. Each
mercury box is provided with a removable perforated cover f', and the perforations
are preferably conical and arranged with their larger ends uppermost. The
perforations are small and numerous, and they have been shown of proportionally
larger size in the drawings for clearness only.
G is a water supply pipe which passes through the side of the mortar box below
the plate F. This pipe G is connected to the pipes g which enter the mercury
boxes, by means of the flexible india rubber pipes g¹, to permit the position of the
mercury boxes to be adjusted. The pipes g have perforated branches inside the
mercury boxes, and are arranged between the surface of the mercury and the covers.
The perforations in the pipes g are in their upper sides so as to drive the water
upward through the perforated cover plates.
H is a tank secured to the top of the mortar box. This tank has chutes h
formed at its ends through which the ore is fed onto the dies. H₁ is an overflow
conduit for discharging the water from the top of the tank. A hole is formed
in the side of the tank and is covered by a plate j. When desired this plate may
be removed and a wire screen can be bolted to the side of the tank in place of it.
J is a faucet for letting water into the tank, and J¹ is a faucet for letting the
water out of the mortar box. The ore is crushed and ground between the stamp
shoes and the dies, and is pushed onto the cover plates of the mercury boxes. The
water coming from the boxes washes up the light particles of earth. The heavy
particles of gold fall into the mercury, and the very small particles of gold become
attached to the plate F from which they can be removed by scraping. The finely
pulverized tailings are carried off by the water which flows out of the conduit H'.
Only one stamp has been shown, but it is obvious that by increasing the width of
the mortar box two or more stamps may be arranged side by side. When two
stamps are used they are preferably arranged to work in opposite directions.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The combination, with a mortar box having two dies, and an amalgamator
between the dies; of a stamp provided with two shoes and a substantially
horizontal arm, and driving mechanism counected to the end of the said arm and
operating to raise and lower one shoe and inove the other shoe horizontally on its
die towards the amalgamator, the said shoes being operated simultaneously and
alternately, substantially as set forth.
2. The combination, with a mortar box having two dies, of a stamp provided
with two shoes and two substantially horizontal arms, a vertical guide engaging
with one of the said arms, and driving mechanism connected to the other said arm
and operating to raise and lower one shoe and slide the other shoe across its die,
substantially as set forth.
3. The combination, with the mortar box having two dies, and the stamp
provided with two shoes, of a water tank secured to the top of the mortar box and
having its ends inclined outwardly and upwardly thereby forming chutes for
conducting the ore onto the opposite ends of the dies, substantially as set forth.
4. The combination, with the mortar box and the two dies, of the stamp provided
with two shoes and a horizontally projecting arm having a series of holes in it, a
driving shaft provided with a crank, a pitman connecting the said crank with the
said arm, a guide shoe pivoted to the pitman, and a stationary guide for the guide
shoe to slide on, whereby a longitudinally reciprocating and a rocking motion is
imparted to the stamp, substantially as set forth.
5. The combination, with the mortar box provided with two dies, and the stamp
provided with two shoes, of the two mercury boxes and the central bent plate F
supported between the said dies, the perforated cover plates, and pipes for admitting
water between the mercury and the cover plates, substantially as set forth.
6. The combination, with the mortar box provided with two dies, and the stamp

page_text: provided with two shoes, of the two vertically-adjustable mercury boxes and the
central bent plate F supported between the said dies, the perforated cover plates,
the branch pipes admitting water between the mercury and the cover plates, the
stationary supply pipe, and the flexible pipes connecting the said supply pipe with
the said branch pipes, substantially as and for the purpose set forth.
Dated this 14th day of November 1893.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.