US1353096A - Stamp-mill - Google Patents

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US1353096A
US1353096A US307680A US30768019A US1353096A US 1353096 A US1353096 A US 1353096A US 307680 A US307680 A US 307680A US 30768019 A US30768019 A US 30768019A US 1353096 A US1353096 A US 1353096A
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stamp
mortar
cylinder
valve
frame
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US307680A
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James W Vanmeter
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B02CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02CCRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C1/00Crushing or disintegrating by reciprocating members
    • B02C1/14Stamping mills

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  • stamp- Mills a citizen of the United States,residing at the city and county of San Francisco and State of California, have invented certain new and useful Improvements in Stamp- Mills, of which the following is a specificain combining with the morta'r andstamp,
  • an engine preferably of the internal como 4 v I My invention relates to the class of stamp-mills
  • Still another advantage lies in keeping the screens clear.
  • the mortar screens are often choked, by fine particles of ore. It is well known that if V the pulp is not discharged at once when reduced to the ,desired fineness, it rapidly slimes, which is detrimental v ment. My device prevents clogging of the shoulders19 on the columns.
  • FigJB is a vertical sectional detail at water circulation.
  • V Y A g Flg. 4 1s a vertical sect1on, fenlarged, of
  • FIG. 5 is a detail section showing the 'compressed air ductsand controlling 'valves.
  • Fig. 61 s a detail section showing the fuel ducts and controlllng valves.
  • Fig. 7 is a detail of theswitch for the ignitionplug. I I
  • 1 is an upright framewith a base 2 and ahead 3, said frame being adapted to'be anchored to a suitable foundation.
  • 5 is a mortar having aldie 4 ananmd with screens 6.
  • the mortar is ,carried by columns'Z to which it is securely lfixed and clamped between the bottom nuts 8 and the I p
  • the columns 7 slide through the head 3*of the frame 1, in suitable bushings 10, whereby the mortar is adapted for reciprocative movement.
  • top nuts '11" curely clamped between top nuts '11" and mortar to rest upon when inactive.
  • 1 5 is a stationary stamp within the 111. 1 tar )5 and over which said mortar moves.
  • the stem 15 of the stamp is fitted in the head ,3 of the frame 1, being secured therein by set screws 16, Figs. 1 and 3, and is held rigid and fixed against upward impact by its bottom shoulderlf? below said head.
  • the head of the cylinder is the usual ignition plug 19, and below the head and above the piston is the combustion chamber 20 of the cylinder, to receive the explosive charge, Figs. 2, 3 and 4.
  • air is compressed by utilizing the weight of the cylinder and mortar on their downward stroke,v and this air acts as a cushion in the operation of the mill, and the air thus compressed is directed, to avoid waste, into the air reservoir from which the air is obtained for the explosive mixture, as will, be presently described.
  • both the combustion chamber 20 and the air compression chamber 22 are W tter-jacketed own at 23, and the piston itself is also provided for water circulation, being made hollow and provided with a central longitudinal partition 24, as seen in Fig. 3.
  • the water enters the hollow piston by the flexible connection 25, and thence circulates over the topof the partition 24, and leaves bythe flexible connection 26, which communicates with the water jacket space 23,
  • the valve mechanism is as follows In the upper end of the cylinder is fitted a tubular valve sleeve or seat '28, Fig.
  • valve 29 The travel of the valve 29 is limited downwardly by the lower seat-shou1der 33 and is limited upwardly by the upper seatshoulder. 34, A stem 35 extends downwardly from the valve 29, and said is fitted with an upper spring 36 and a lower spring 37, the former spring tending to lift the valve and the latter spring .to lower it. i
  • the stroke of the valve 29 is effected as follows.
  • Fig. 4c 38 is a swinging catch pivoted in the cylinder at 39, said catch operating alternately above and below a lug. 4.0 0. the
  • valve stem 35 to prevent the valve from rising when the catch engagement is above the lug and to prevent it from descending when the engagement is-below the lug.
  • spring 41 acting on the catch 38 holds it against the valve stem.
  • Fig. 5 is shown the valve controlled connection 'to the air compression cushlon' ing air inlet valve which'communicate's at one side with the exterior air, and at the other side with a port 49 into the chamber 22, (Fig. 1).
  • connection 51 is a spring controlled outlet valve from said chamber port 49, the compressed air passing up through a duct 51 leading to the connection 51 from the air reservoir, Figs. 1 and 5, said connection 51 having a spring controlled check valve 52 which permits the air from the reservoir to pass freely into the combustion chamber, but allows no burnt gases or back pressure into the air duct 51.
  • the compressed air stored up in the reservoir may be usedto run the engine temporarily in emergencies.
  • Figs. 4 and 6 are shown the fuel pump.
  • a bore in the cylinder 13 is a bore in the cylinder 13, the upper portion of the bore having a communlcation 5%, Figs. 6 and 1, with the compressed air connection 51 from the air reservoir.
  • a piston 55 which has a stem 56 extending downwardly through an adjustable bushing 57, the projecting lower end of said stem being adapted to contact with. the head 3 of the frame 1 on the downward stroke of the cylinder.
  • 58 is the inlet valve of the fuel connection and 59 is the outlet valve communicating with the fuel pipe 60 leading to and through the top of the cylinder and opening into thecombustion chamber 20Figs. 4 and 1.
  • the ignition of the charge is effected by the contact of the switch terminal 46 with the collar 17 conveniently carried on the water pipe 27(see Fig. 7).
  • a stamp-mill comprising a fixed frame; a mortar mounted on the frame for reciprocative movement; a stamp fixedly mounted in the. frame and. over which the reciprocative mortar plays to crush the ore by im pact against said stamp; a cylinder connected with the mortar; a piston fitted in said cylinder fixed against reciprocative movement; fluid controlling connections to re ciprocate said cylinder on said fixed piston; andmeans carried by the cylinder and actuated by contact with the fixed frame for operating said fluid controlling connections.
  • a stamp-mill comprising a fixed frame; a mortar mounted on the frame for reciprocative movement; a stamp fixedly mounted in the frame and over which the reciprocati've mortar plays to crush the ore by impact against said stamp; an engine, the reciprocative member of which is connected with and reciprocates the mortar; means for reciprocative cylinder of an engine fixed to the other end of said columns; a stamp fixed in the head of the frame and over which the mortar plays to crush the ore by impact against said stamp; a stationary piston supported on the head of the frame, and over which the engine cylinder plays; means forv reciprocating the cylinder; and means carried by the cylinder and operating by contact with the frame head to actuate said reciprocating means.
  • a stamp-mill comprising a fixed frame
  • a mortar mounted on the frame for reciprowith a chamber in the cylinder to form an air cushion for the reciprocative mortar.
  • a stamp-mill comprising a fixed frame having a head; columns mounted slidably in said head for reciprocative movement; a mortar fixed to one .end of said columns; a cylinder to the other end of said columns; a stamp fixed in the head of the frame and over which the mortar plays to .crush the ore by impact against said stamp;

Description

J. w. VANMI I'TER.
STAMP MILL.
1,353,096. 'IAPPLICATION FILED JUNE 30, I919- I I fl I1"\1 z I O 7. I 0 0. I 7 1,2 IIII Z6 a I 12.
7 10; jI I 5. II I I I 9. l7] F I II I 9 I a I //7 1, ,4. P I 6.
II III I J I I 8 W12 g A A WITNESS IN VEN TOR QM: I 4W5 ,wmz
A TTORNE YS J. W. VANMETER.
' STAMP MILL.
I 4 APPLICATION FILED 1UNE30.1919- I 1,353,096. PatentedSept. 14,1920.
5 SHEETS-SHEET 3- 37 f r 14. 2 J .1 7 zz.
1 Ii 4 \u 1 I 15 z; I I 7 lg: f v
. INVENTOR. qfiwlk a, M;
BY flwwwz:
ATTORNEYS J. W. VANMETER.
STAMP MILL.
APPLICATION FILED JUNE 30. 1919.
1,353,096. Patented Sept. 14, 1920.
5 SHEETS-SHEET 4.
I -39 r' 15, I 3 58 5 4 22 45 i 14 I Z0. I 2. 55' I "I 55 I I 43; 15 I 14 5 13 I I II 10 10 I v j 151! I I WITNESS F= /'z:7 4 v INVENTOR I I 611VZIZZ w? 5? M BY mow/ MW;
ATTORNEYS I. w. 'VANMETER.
STAMP MILL.
APPLICATION FILED JUNE 3%1919- v 1 ,353,096, Patented Sept. 14, 1920.
' 5 SH-EETSSHEET 5- INVENTOR mu 5 III,
UNITED", STA
B PATENT,0
PRICE STAMP-MILL.
Application filed June 30,
To all whom it may concern:
' Be it known that I, JAMES W. VANMETER, a citizen of the United States,residing at the city and county of San Francisco and State of California, have invented certain new and useful Improvements in Stamp- Mills, of which the following is a specificain combining with the morta'r andstamp,
an engine, preferably of the internal como 4 v I My invention relates to the class of stamp-mills;
lVIy millthough comprising a mortar and a stamp, dilfers essentially from the ordinary stamp-mill, in that instead of the stamp reciprocating and playing into and out of afixe d mortar, the mortar recipro cates over a fixed stamp, and by this: movement CILlSllBSltS ore against the stamp.
This reversal of the ordinary operation resultsin several distinct advantages which tar.
it isthe object of my invention to attain.
One of these advantages is that the heavier and finer particles, due to the jar of impact of the moving mass, gravitates H to the bottom quicker while thelighter and f larger particlesseek the top and thus come in direct contact with the stamp. 'Conse- Y quently, a new surface of the ore is conv stantly presentedto the stamp. This effect eliminates sliming to great extent, the ore Y mass chan ging relative position of particles at each upward stroke and jar of the mor-' This cannot be the case with a dropping stamp which willstrike the ore on a practically unchanging top, the bottom of the mass remaining intact. Bymy reversed arrangement I thus increase the crushing capac ty. Moreover by this constant, re
.peated andrapid changing of the ore due to the moving and jarrlng mass, I get a better battery amalgamating efi'ect within the mortar, by bringing the fine gold .in quicker contact with the mercury.- I
Still another advantage lies in keeping the screens clear. In common practice the mortar screens, are often choked, by fine particles of ore.. It is well known that if V the pulp is not discharged at once when reduced to the ,desired fineness, it rapidly slimes, which is detrimental v ment. My device prevents clogging of the shoulders19 on the columns.
screens, because any particles of. orethat may tend to clog are thrown oil by the rapid and forcible impact of the mortar v against the stamp; 55,
With hese .ends in iew my invention primarily consists in a stamp-mill compristo the treat- Specification of Letters Patent. Patented 14, 1920.
1919. Serial No. 307,680.
ing a fixed frame, a reciprocative mortar mounted in the frame; and a fixed stamp carried by the frame, and over whichthe mortar plays to crush its ore by impact against the stamp. Moreover, in"order to make my mlll practical in constructionand operation, my invention consists, further,
bustion type, the reciprocative member of which is connected with the mortar, and in operating this engine automatically by the contact o f its control connections carried the cylinder with thefiXed frame. By this form of motive power anddevice my stamp-mill is made morevaluable' by increasing its capacity, yiel'ding better amalgamating results, cheapness in construction {and less weight; also more economical in Referring to the 'accompaiiyin'g draw e e v F gure l is an elevation of my stamp-mill. F1g. 2 1s a vertical section of the same partly in elevation.
FigJB is a vertical sectional detail at water circulation. V Y A g Flg. 4 1s a vertical sect1on, fenlarged, of
right, angles to Figsf1 and'2, showing the the upper portionof the mill, showing the Fig. 5 is a detail section showing the 'compressed air ductsand controlling 'valves.
Fig. 61s a detail section showing the fuel ducts and controlllng valves.
Fig. 7 is a detail of theswitch for the ignitionplug. I I
1 is an upright framewith a base 2 and ahead 3, said frame being adapted to'be anchored to a suitable foundation. 5 is a mortar having aldie 4 ananmd with screens 6. The mortar is ,carried by columns'Z to which it is securely lfixed and clamped between the bottom nuts 8 and the I p The columns 7 slide through the head 3*of the frame 1, in suitable bushings 10, whereby the mortar is adapted for reciprocative movement.
To the upper ends of the columns is secontacts for the internal combustion enme. I a
curely clamped between top nuts '11" and mortar to rest upon when inactive.
shoulders 12, the cylinder 13 of an internal combustion engine, said cylinder being adapted for reciprocative movement, where by through the columns '7, the mortar is given its movement. The cylinder 13 moves upon a stationary piston 14, the lower end of which rests firmly and solidly upon the head 3 of the frame 1, as seen in Figs. 2 and 3.
1 5 is a stationary stamp within the 111. 1 tar )5 and over which said mortar moves. The stem 15 of the stamp is fitted in the head ,3 of the frame 1, being secured therein by set screws 16, Figs. 1 and 3, and is held rigid and fixed against upward impact by its bottom shoulderlf? below said head.
18 is a cushionmember in the base 2 of the frame 1, to serve as a buffer for the It will now be seen that if the cylinder be given a reciprocative movement, it will lift and lower the mortar, with the effect of subjecting the ore in the mortar to impact with the stationary stamp, which is the ,operation sought, 1
The means for reciprocating the cylinder 13 will now be described.
In the head of the cylinder is the usual ignition plug 19, and below the head and above the piston is the combustion chamber 20 of the cylinder, to receive the explosive charge, Figs. 2, 3 and 4.
The piston 14, below its upper end, is forme d'w-ith a packed enlargement 14:, and between this enlargement and a shoulderQl in the cylinder bore is formed an air compression chamber 22. In this chamber air is compressed by utilizing the weight of the cylinder and mortar on their downward stroke,v and this air acts as a cushion in the operation of the mill, and the air thus compressed is directed, to avoid waste, into the air reservoir from which the air is obtained for the explosive mixture, as will, be presently described.
By referring to Fig. 3 it will'be seen that both the combustion chamber 20 and the air compression chamber 22 are W tter-jacketed own at 23, and the piston itself is also provided for water circulation, being made hollow and provided with a central longitudinal partition 24, as seen in Fig. 3.
The water enters the hollow piston by the flexible connection 25, and thence circulates over the topof the partition 24, and leaves bythe flexible connection 26, which communicates with the water jacket space 23, The
water thencepasses to the top of the cylinder and issues therefrom by a pipe 27 which leads down to'a point where it discharges directly into the mortar, as seenin Fig. 3. The water thns Used has the double function of cooling the parts by and through which it circulates, and being thus heated is used as hot water the mortar, to aid the process of amalgamation therein, and to reduce the danger of the castings breaking when worn. This is a decided advantage where mills are used in a cold climate. The valve mechanism is as follows In the upper end of the cylinder is fitted a tubular valve sleeve or seat '28, Fig. 4, in which reciprocates a piston valve 29 which controls the air inlet port'30 to the combustion chamber 20, and also controls the upper series of ports 31 in said valve seat which communicate with the inlet port .30, and the lower. ports .32 which admit the air to said valve seat from the air connection leading from the compressed air reservoir, as will .be presentlydeseribed. .When the piston valve 29 is lowered it opens the ports 30 and 31 toexhaust the burnt gases through the open top of the val-vesleeve or seat, and when it is raised it connects the ports Y31 and 32, to admit compressed air to the combustion chamber.
The travel of the valve 29 is limited downwardly by the lower seat-shou1der 33 and is limited upwardly by the upper seatshoulder. 34, A stem 35 extends downwardly from the valve 29, and said is fitted with an upper spring 36 and a lower spring 37, the former spring tending to lift the valve and the latter spring .to lower it. i
The stroke of the valve 29 is effected as follows.
In Fig. 4c, 38 is a swinging catch pivoted in the cylinder at 39, said catch operating alternately above and below a lug. 4.0 0. the
valve stem 35, to prevent the valve from rising when the catch engagement is above the lug and to prevent it from descending when the engagement is-below the lug. spring 41 acting on the catch 38 holds it against the valve stem.
42 is a vertically movable r0d ,.,the lower end of which projects below the cylinder body and said rod is supported by acollar 43 and isheld down by a spring-4 reston a collar 45 .of the rod: and adapted at its upper end to come in contact under the catch 38, when the rod movesupwardly, due to the contact of the lower projecting end of said rod with the head 3 of the frame 1. i r I It will now be seen that when the cylin- .der 13 moves down [so that the'end of rod 42 contacts with the fixed frame head 3, said rod will move up and through the spring .4 w l el as th a ch 38 fr m abov the lug 40 of h valve stem 35. S c due to' the same downward movement of the cylinder, he Sp ng 36 said' Va tem .is. compressed, said spring will noijwv', when the catch 38 is released, throw the stem up, thus causing the piston valve 2 to rise n bring the ports 31 and 32 into. commnnication with the combustion chamber 20 th ugh p 3 s s o ha g th la er" with compressed air, the catch 38 returning under the lug 40 and holding the valve up.
On the upstroke of the cylinder, the catch 38 having by the impact of the ore against the stamp been jarred loose from under the lug 10, the spring 87 pulls the valve 29 down, permitting exhaust from the combus-Y tion chamber.
In Fig. 5 is shown the valve controlled connection 'to the air compression cushlon' ing air inlet valve which'communicate's at one side with the exterior air, and at the other side with a port 49 into the chamber 22, (Fig. 1).
50 is a spring controlled outlet valve from said chamber port 49, the compressed air passing up through a duct 51 leading to the connection 51 from the air reservoir, Figs. 1 and 5, said connection 51 having a spring controlled check valve 52 which permits the air from the reservoir to pass freely into the combustion chamber, but allows no burnt gases or back pressure into the air duct 51. The compressed air stored up in the reservoir may be usedto run the engine temporarily in emergencies.
In Figs. 4 and 6 are shown the fuel pump.
53 is a bore in the cylinder 13, the upper portion of the bore having a communlcation 5%, Figs. 6 and 1, with the compressed air connection 51 from the air reservoir. In this bore is fitted a piston 55 which has a stem 56 extending downwardly through an adjustable bushing 57, the projecting lower end of said stem being adapted to contact with. the head 3 of the frame 1 on the downward stroke of the cylinder. 58 is the inlet valve of the fuel connection and 59 is the outlet valve communicating with the fuel pipe 60 leading to and through the top of the cylinder and opening into thecombustion chamber 20Figs. 4 and 1. N-hen the stem 56 strikes the fixed frame head 3, the piston is forced up and thereby opens the inlet valve 58 and closes the outlet valve 59, thus sucking in the fuel to the lower side of the piston in the bore 53. When the cylinder l3 rises. the compressed air from the connection 54: forces the piston down and thus forces fuel out through valve 59 and pipe 60 into the combustion chamber.
The ignition of the charge is effected by the contact of the switch terminal 46 with the collar 17 conveniently carried on the water pipe 27(see Fig. 7).
The complete operation may now be described. In Figs. 2 and 4, the mortar 5 and cylinder 13 are on the downward stroke, and the exhaust gases are escaping from the combustionchamber 20byway of the ports 30 and 31, and the-open. upper end of the valve sleeve or seat 28. The spring 36 of the valve stem is being compressed and the lower spring 87 is expanding. The spring 36 is tending to forcethevalve 29 up, but said valve is held by the catch 38bearing on top of lug 4:0. Butthe' moment the end of the rod a2 contacts with the fixed head'3 of the frame 1, the upward move-' ment of the spring l disengages the catch 38 from above the lug 40, and thereupon the spring 36, throws up, the valve 29, bringing the ports 31 and 32 into communication both with the compressed air'reservoir and with" the combustion chamber120, and thus air is a'clmitted to the latter. Fuel having been sucked into the pump by the rise of piston 55, due to contact of the stem 56 with the head 8, the mortar and cylinder now start on their upward stroke,an'd the stem 56 being relieved, its piston-is forced down by the compressed air through connection 54, and their charge of fuel is delivered through pipe 60 to the combustionchamber. Then driven up with great pressure, causing the ore in the mortar to strike the stamp. The
impact and sudden jar causes the swinging catch 38 to disengage from below the lug 10, and the spring 37 then pulls the valve 29 down closing the air supply and allowingthe exhaust gases to pass out.
I claim 1. A stamp-mill comprising a fixed frame; a mortar mounted on the frame for reciprocative movement; a stamp fixedly mounted in the. frame and. over which the reciprocative mortar plays to crush the ore by im pact against said stamp; a cylinder connected with the mortar; a piston fitted in said cylinder fixed against reciprocative movement; fluid controlling connections to re ciprocate said cylinder on said fixed piston; andmeans carried by the cylinder and actuated by contact with the fixed frame for operating said fluid controlling connections.
2. A stamp-mill comprising a fixed frame; a mortar mounted on the frame for reciprocative movement; a stamp fixedly mounted in the frame and over which the reciprocati've mortar plays to crush the ore by impact against said stamp; an engine, the reciprocative member of which is connected with and reciprocates the mortar; means for reciprocative cylinder of an engine fixed to the other end of said columns; a stamp fixed in the head of the frame and over which the mortar plays to crush the ore by impact against said stamp; a stationary piston supported on the head of the frame, and over which the engine cylinder plays; means forv reciprocating the cylinder; and means carried by the cylinder and operating by contact with the frame head to actuate said reciprocating means.
4. A stamp-mill comprising a fixed frame;
. a mortar mounted on the frame for reciprowith a chamber in the cylinder to form an air cushion for the reciprocative mortar.
5, A stamp-mill comprising a fixed frame having a head; columns mounted slidably in said head for reciprocative movement; a mortar fixed to one .end of said columns; a cylinder to the other end of said columns; a stamp fixed in the head of the frame and over which the mortar plays to .crush the ore by impact against said stamp;
a stationary piston supported on the head of the frame and over Which the cylinder plays; and means for reciprocating said cylinder. I
In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.
JAMES W. VANMETER, Witnesses:
VVM. F. BoorH, D. B. RICHARDS.
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