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Патент USA US2112343

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Marc'h 29, 1933.
N. LES-naa»` ET AL
2,112,343
`> PRESSURE CASTING MACHINE
Filed July :5, 1935
2 sheets-sheet 1
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INVENTORß
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March 29, 1938.
N_ LESTER ET AL
2,112,343
PRESSURE CASTING MACHIN.
Filed July 3, 1935
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ATTORNEYÖ
2,112,343
Patented Mar. 29, 1938-
UNITED STATE s - PATENT
,
2,112,343
OFFICE
d
vPRESSUREcastano. MACHINE
` » Nathan Lester, Cleveland Heights, Ohio, and‘Wil
`liam M. Lester, Leominster, Mass.,- assignors
to Lester Engineering Company, Cleveland,
Ohio, a corporation of Ohio
Application Julyïa', 1935, serial Navzassa
1c claims.
(ci. .c2-ss)
The present invention relates to an apparatus
l Now referring more particularly to Fig. 1, the
for casting metal under relatively high pressure
pressure casting 1machine shown therein consists
wherein a charge of metal is forced from a pres-
of a supporting base I carrying the horizontal tie
sure chamber into a permanent mold cavity de-
rods 2, the end tie plate 3„and the upper tie rods
fined by a pair of separable die blocks.
The general object andnature of theinvention
is to transfer a measured charge of metal, sufli-
l (only one each of the tie rods 2 and l being
shown). A die plate 5 is carried by the right
hand end of the tie rods 2 and l, or upon the
cient to completely fill the mold cavity and gate,
-from a melting pot, to a pressure chamber, and
` to eject a quantity of metal therefrom into the
mold cavity without exposing such metal to the
atmosphere and without entrapping any air or
end opposite to that of the tie plate 3. A movable
die plate 6 is also carried upon the intermediate
portion of the tie rods 2 and `I. The die plates 5
and 6 are adapted to carry the die blocks 1 and
8 respectively, whose opposed faces define a mold
5
air bubbles in the casting charge.
cavity 9.
chamber. Another object of the invention is to
provide a measuring plunger adapted to vary the
volume capacity of the pressure chamber and to
maintain the casting charge in a compact mass
until it is in position to enter4 the mold cavity.
A further object is to provide means for auto-
carried upon the movable Plate l2 by means 0f
a screw ‘jack mechanism I3 whereby the position
of the die plate 6 with respect to the movable
plate I2 may be variably regulated. The last
described mechanism for actuating the die plate 6
is not claimed as novel in the present invention,
matically‘regulating the position and movement
of such measuring plunger.
since it is embodied in the subject matter and
explained in detail in the copending application 25
Still another object of the invention is to provide a melting pot and furnace structure which
can be quickly and` easily removed and replaced
from the casting machine assembly. Additional
of William M. Lester, Serial No. 5,438, flied Febru
ary 7. 1935
, A pressure Casting Chamber 0r Cylinder l5 1S
mounted in the> die plate 5. A pressure plunger
A further -object of the invention is to provide
means for ejectlng `surplus metal or solidified
15 g“slugs” from the charging chutethrough which
the molten metal isv transferred into thev pressure
i25
,
v
objects and advantages shall become apparent
I6 enters the right hand end of the casting cyl
during the following description.
lnder I5 and is connected to the piston rod I1
o
To the accomplishment of the foregoing and
related ends, said invention, then, >consists of
the means hereinafter fully described and par35
.
Toggle link mechanism indicated generally-by
the numeral I0, together with the hydraulic ac 15
tuatlng cylinder II, connects the end tie plate 3
to the movable die plate 6. The die plate 6 is
0
leading to the hydraulic pressure cylinder I8.
Flexible connections I9 and 20 communicate with
the interior of the pressure plunger I6, which yis
ticularly pointed out in the claims.
¢ hollow and are for the purpose of circulating a
The annexed drawings and the following de- cooling medium Such as water or oil within
scription set forth in detail certain mechanism
embodying the invention, .such disclosed means
the interior of the plunger I6. The hydraulic
cylinder I8 is mounted upon the base I by means
constituting, however, but one ofk various ‘me-
of a supporting bracket 2|.
’
A charging Chute 24 leads from the pressure 40
casting cylinder I5 to the metal melting pot 26.
The melting pot 26 is in turn mounted in a. heating
furnace `structure 21. The melting pot 26, the
heating furnace 21 and its housing 2B is mounted
upon the supporting rollers 29 whereby the melt
ing pot and furnace can be rolled laterally, that
is, in a direction normal to the plane of Fig.v 1,
from under the casting machine, merely by re
moving the charging chute 24. In this manner,
a melting pot and furnace which needs repair 50
may be very easily removed and replaced in posi
tion with respect to the casting machine, or the
melting pot and furnace containing a different
composition of metal may be conveniently sub
tion betweenl the measuring plunger shaft and
55
stituted when desired.
chanical forms in which the principle of the in1
In said annexed drawings:-.Fig. 1 is an elevational view in section of the
assembly of the machine embodying the principle
of our invention; Fig. 2 is an enlarged sectional
45 view ofthe charging chute and pressure chamber taken upon a plane normal to that of Fig. 1
and substantially «along the -line v2--2 thereof;
Fig. 3 illustrates an alternative form of construction for the parts shown in Fig. 2; Fig. 4 is an
enlarged fragmentary sectional view taken upon
`a plane normal to that of Fig. 1 and substantially
along the line 4-4 thereof, showing the connec
40 vention may be used.
the auxiliary resistance shaft.
2
»guasta
' The upper- portion SII of the charging chute 2|
has a recess for the reception of the rectangular
exterior wall II of the pressure cylinder Il.- A
transverse shaft l2 meshes with a gear rack II
removable cap_32à holds the charging chute por
tion 3l in position with respect to the'ca'sting
ingbosses Il and Il extending from the die plate
i and themovable plate I2 respectively.
y cylinder Il. Suitable studs 33, Il fasten the cap
22 to the face of the charging chute portion Il.
The upper end of the cha?giug‘chute' pamage 2l
intersects and' communicates with the interior ol
10 the casting -cylinder II, as indicated at Il.
Fior-the purposesvof convenient fabrication,
and machine practice, the rectangular cylinder
housing 3i may be made into two-.pieces Joined
together> along the lparting line Il in the same
15 plane as the arial center of the charging chute
passage.
~
A vacuum passage ß leads from >the upper end
of the charging chute passage 2l ~to the port
21 which in turn is connected to the vacuum
on the end of the auxiliary shaft I4. Theaux
iliary shaft Il is carried by downwardly project
' It will thus be seen that the measuring plung
er shaft II and the- auxiliary shaft Il are so
connected'by the cross shaft l2 that movement of
either one in a given direction will be transmitted
into movement of the other in an opposite direc
tion. For‘example, when the measuring plunger
Il and its shaft il are moved in a left hand
direction with respect to Fig. 1,- the cross con
necting .shaft I2 will be rotated in such a direc
tion'. as to transmit the left-hand movement of
the shaft II into a right-hand movement of the
is
shaft M.
f The _left hand end of the shaft I4 is connected
to the,adJustable,_ threaded spindle or shaft Il'
20 conduit 38. The vacuum conduit 3l leads to a. “hy-means
of the sleeve `Il and a friction pack-4
vacuum pump or motorV (not shown). l`The vac
ing gland composed of the bushing I2 and the
uum passage 33 is of cylindrical form and 'a friction packing material Il.y 'I‘he shaft l0
plunger or piston il is mounted therein. The
upper end of the piston 39 carries a gear rack
III adapted to be engaged by the gear segment
4I on the end of the lever 42. Thevlever l2 is
pivoted at the point 43 and carried by the hous
threadably engages an internally threaded sleeve
I4, the latter being fixed to the base I. The
outer _end oi' the shaft il is squared as at Il
for the’ reception of a suitable rotating tool or
wrench whereby 4the position of the shaft l0
ing‘ Il which in turn is threadably mounted as may be adiustably regulated with respect to the
at“` to the upper end of the charging chute 24. fixed base I.
" '
The housing Il alsoserves as a guide for the
The
operation'`
of
the
-automatic measuring.
reciprocal movement of the enlarged upper end plunger Il4 ' and' its i above describedf connectingy
46 of the piston II. A connecting rod 41 connects `
the >outer end of the lever 42 to the movable tie',`
when the v«casting cynnder- unis nues with
plate I2. Thus movement of the die plate t and - molten metal by -the- action of the vvacuum
¿mechanismlisas'follov'o's:-`
435
40
'
'
l
"
l
so` Í
'
of the movable plate I2 operates `to oscillate the vthrough the passage irland through the charging
lever 42 about its 'pivot point vß and to thereby chute passage 2l, the pressure -plunger Il is
raise and lower the piston 39. `When the piston then moved in a left hand or dischargingv direc
39 reaches its uppermost position, fas’ shown in ` tion. Compression of the metal charge in the
Fig. 2, the vacuum passage port 31- will be opened cylinder Il tends to force the measuring _plunger
andthe vacuum placed in communication withthe 50 in- a left hand direction, or outwardly with re
charging chute passage 25 and the interior of the spect to the cylinder II. Such left hand move 40
casting cylinder I5.- On the, downward movement ment of the measuring plunger Il and its shaft
of the piston 4*39,„the vacuum passage port l1 II is transmitted through thefcross connecting
will be closed and?> continued downward move
shaft 52 to the auxiliary shaft 5I. tending to
ment will extendï'the piston 38 into the vacuum..v draw the latter in a right hand direction. But
passage> ,3Q and the> upper end of the charging the right hand movement of the shaft M is re 45
`chute passage „2B-whereby excess- metal which sisted by virtue of the friction packing Il in the
might have‘frozen out in the upper end of the ` sleeve 6I. In this manner, the left hand or 'out
50
passageßïjand in the passage 36 will be forcibly
ejected and dropped back into the melting pot 26.
For the Vpurpose of conveniently removing and
replacing the charging chute, the alternative
form of construction as shown in Fig. 3 may be
4ward movement of the measuring plunger 80 with
respect -to the lcasting cylinder Il is resisted,
but the pressure exerted ybythe pressure plunger
Il is suñlcient‘to overcome such’resistance until
thev shoulder“ on the >measuring plunger Il
employed. In Fig. 3,'the charging chute ismade _. abuts against the >face of> the die plate 6. At
55 in the form of a separableelement 24' .which
threadably engages the housing 30’ as at Il. A
hexagonal portion 49 on the outer surface of-the
charging I chute 24' is for the reception of a
wrench whereby the chute 24’ may be conven
iently screwed on or unscrewed from the hous
ing 3U'
Y
-
Directingl attention to Fig. I, a measuring
plunger B0 extends- >through the die blocks 1
and l and is adapted to enter the left hand or
discharge end >of thecasting cylinder I5. The
end oi.' themeasuring plunger 50 and the end
-of the pressure plunger Il thus define end walls
in the pressure cylinder I5. The left hand or
outer end II of the measuring plunger 50 is
70 journalled in the movable die plate 6 and has
a gear rack which meshes with the‘gear teeth
on the transverse shaft 52. The shaft 52, as
will be best seen in Fig. l, is lournalled in a re
cess in the die plate 6 and held therein by
75 means of the cap screw 53. -The lower end of the
this point the right Íhand-.end of the measuring 55
plunger.“
cleare'dit‘he sprue opening B‘I'to
the'moldcavity ‘9, as indicated by the dotted line
08 and, further movement of the pressure plung
er Ilforces the metal charge into the mold
cavity 9. At the next stage of operations, when 60
the movable die plate 6 is moved in a left hand
direction in order to open the die >blocks 1 and
8. such movement _will tend to rotate the cross
connecting shaft l2 inra counterclockwise direction as viewed in Fig; 1; but since the shoulder 65
I6 abuts against the face of the die plate i, such
counterclockwise rotation will not be possibleand the shaft 52 will therefore become locked,
with,the result that the position of the shaft
Il' with respect to the movable die plate l is 70
also locked. Hence left hand movement of the
ydie ~,plate I, due to the locking of the cross
shaft 52 will be transmitted into left hand move
ment of the shaft 54, into the space 69 between its
left hand end and the end of the threaded shaft
1
9,119,848
i
,
,
p
ì
ì
3
l‘l. On closing movement of the die blocks 1 and
having a meltingpot. 'a pressure'chalnber. for re--
’0, the resistance exerted by the Afriction packing
sure,'and a pressure
connectedto said4
chamber for transferring jiluid metal thereinto‘`
l, or on right-hand movement of the die plate ceiving and
"u will tend to hold the shaft u in place with
the shaft Il and measuring
plunger Il in a right hand direction.` and back
4 and thereby `move
into-its original starting position,v asäf'shown m.
`10v
Fig.
1.
i
4
«
,
'
.
`
i
i ' `In order to variably regulate the initial start
ing position of the measuring plunger Il, and
. incidentally, of course, to vary'the volume capac
` ity of the cylinder Il, the position ofthe thread
iluid metal >under _pres
from the melting- pot', the combination of means
the result’that the cross shaft „will be rotated
ina clockwise direction with respect‘to Pig. l'.
,
A
for electing excess metal from said passage back '
.
luto #sid Bie-111118 90h»
r
l
2.,In a pressure. castingmachineof the'type
having a melting pot, ia' pressure vchamber' for
„receiving and discharging fluid metal-under pres
Vsure, and a pressure 4passage connected Lto. said ’
' chamber . for transferring fluid metall thereinto`
-
from the melting pot. the combination of means -
for ‘opening‘and closing saidv passage and also.
edshaft
I0 withrœpecttothenxedbase I is vfor electing excess mctalfromsaidpassage back
,
15
` . varied. Thus, if the threaded shaft IU is moved
in a left hand-direction. such movement will
_be transmitted through the shaft Il. the cross
'shaft l2 to the :measuring plunger Y“,_withf the
20 result that the latter will move further into the
into »said melting
„
lmapressurecasting
„
„
.
i
'
ofthe-tm;
having ameltlng potpapressure“ 'reim
" berfor‘re».
ceiving land discharging fluid
under pres
sure. ‘and a vacuum-passage'connectedto .said
' `castingcylinder Il and >thereby reduce the vol
ume- capacity of `the latter. " Gouversely,l right
. 25,
` ’
the meltingpot, the combination of means for
measuring
thel amount of metal discharged from
hand'` movement of the threaded shaft “_ lwill
move the measuring plimger llin aleft -`hand said chamber, and 4means >for electing excess
direction or outwardly _with respect >to the' cyl , metal from said passage back into ’said melting
inder il resulting inagreater' volume-'capacity
` of the latter. In4 this manner, the, metal cast
\ `ling charge `received and delivered bythe cast
4,'1na pressure casting machine of _the type ,
' having'a melting pot.' a pressure
for
receiving and dischargingv ?uid'metal under ,pres
Asure.,an¢,i
a
passage connectedto said'
quired and demanded.
'
'
'
It should be noted that the lower end of the chamber for drawing iiuid thereinto from said/_
ing cylinder I 5 may be adlustably varied fas frei.
, charging chute 24 extends below4 thelevel 1I of
melting pot, the combination .ofmeans'movable
`the metal in the melting pot 2l. `An inert mate Vwenn; ¿the interior orma enamberfrer redsun: » ^
rial yspread over thetop ofthe metal in the the discharge of metal `therefroin‘fand also for "
melting
pot 2l serves to seal -the metal from lvarying the volume capacityof l‘said chamber,
,35
.
for, electing excessmetal fromsaidf j
_v
‘ atmospheric contact. Thus, it will'be seen that-l Á and means
4
,
the above described pressurev casting machine passage backiniaosaid'meltingpot~` '
5.'In a pressure'` casting Au_ia'chine of 'the type:` '
`accomplishes the functions and results of receiv
having a meltingpot, aj pressure chamber for re-'
« ` ing a measured quantity of molten metal from
ce'iving and discharging fluid vmetal under 'pres-~_
the
`melting
pot
without
exposing
the
metal
to
40
sure,
.and a »vacuum passage' connected -to said
oxidation by contact with the atmosphere, trans
chamber forl drawing ‘fluid thereinto lfrom said
fers such measured charge of metal `in la Vcom
'pact body to the opening into the mold cavity. melting pot, the combination of means movable
and also elects any solidified or frozen out slug withl the ‘interior of said chamber’ for resisting`
into the casting cylinder the discharge of metal therefrom» and also forl 45
45 from thefeed
back into the melting pot. Theabove described varying thel volume `capacity of said chamber, and means for opening> and closing saidpassage
machine also effects a convenient means for ad
and also for electing excess metalìfrom said pas#
' lustably varying the capacity of the casting cyl
inder, and correspondingly, the amount of the sage back into said melting pot.
50 , measured metal charge.
`
, 6. In a pressure casting machine of the type
The above described preferred >embodiment: of ' having a melting pot. separable die blocks vdefin
ing a mold cavity, means for openingand clos
our invention of course discloses the use of 'vac
uum pressure for transferring the molten metal ing said blocks, and a pressure _cylinderand
from the melting pot 28, through the charging plunger therein for discharging fluid- metal .into 55
said cavity, the combination'of a secondïphmger
chute 24 and to the pressure cylinder II. How
ever, it should be equallyvwell understood that carried by one of said blocksy and movable, into an' equivalent pressure means can be utilized and out of the discharge end- of said. cylinder,
without transcending-the spirit of the invention. the> pressure generated by said „mst-named
plunger being ,adapted to movey said ’second
For lexample, instead of a vacuum communicat
plunger outward with respect to said cylinder,
60‘ ing with the >upper end of the charging chute
l passage 25, the top of the vmelting potfi" could I ` the> closing movement of said blocks being adaptlf
be hermetically sealed and a'greater thangatmos-- ved‘to move said second plunger inwardly with
pheric pressure introduced therein whereby the‘ lrespect to said cylinder,I and means> for-adjust
molten metal would be forced up through the » ably regulating the extent of such inwardmove 65
charging chute 2l and' into the interior ofthe
"1. In al pressure casting machine of the type
` pressure casting cylinder i5.
. Other modes of applying the principle of our having a melting pot, separable die blocks de
ment.
.
`
l
»
«
fining a' mold cavity, means ‘forïopening and clos
ing said blocks, anda pressure cylinder and
plunger therein for discharging fluid metal into 70
stated by any of `the following claims or the said cavity, the combination of a second plungercarried by one of said blocks‘and movable into
equivalent of such stated means‘be employed.
and out of the discharge end of said cylinder,
We therefore particularly point `out and' dis
l>means for stopping the outward movement of
tinctlyclai‘m as our inventionz--said secondplunger at a point where dts end 75
75 >1. vIn a pressure casting machine oi' the type
invention may beV employed instead of the one
` explained, change being made as> regards the
70 mechanism herein disclosed, provided the 'means
4
2,112,343
has cleared the entrance lto said cavity, the pres
sure generated by said mst-named plunger being
ment _of said blocks being adapted to move said
second plunger inwardly with respect to said cyl
` adapted to move said second plunger outwardly
with respect to said cylinder, the closing move
inder, a melting pot, a vacuum passage termi
nating adjacent 'the juncture of said chute and
ment of said blocks being adapted to move said
second plunger inwardly with respect to said cyl
of said cylinder, and means for ejecting excess 5
metal from said chute back into said melting pot.
inder, and meansfor adjustably regulating the
13. In a pressure casting machine of the _type
having a melting pot, separable die blocks defin
extent of such inward movement.
8. In apressure casting machine of thetype
10 having a melting pot, separable die blocks deñn
ing a mold cavity, means for opening and closing
said blocks, and a pressure, cylinder and plunger
therein for discharging fluid metal into said cav
ity, the combination of a second plunger car
15 ried by one of said blocks and movable into and
out of the discharge end of said cylinder, means
for stopping the outward movement of said sec
ond plunger at a point where its end has cleared
the entrance of said cavity, means for resisting
20 the outward movement 'of said second plunger
with respect to said cylinder, the pressure gen
erated by said first-named plunger being adapt
, ed to move said’second plunger outwardly with
respect to said cylinder, the closing movement of
25 said blocks being adapted to move said second
plunger inwardly with respect to said cylinder,
` and means for adjustably regulating the extent
of such inward movement.
9. In a pressure casting machine of the type
30 .having a melting pot, a pressure cylinder and a
plunger therein, and a charging chute commu
nicatingv between said pot and said cylinder, the
ing a mold cavity, means for opening and clos
ing said blocks, a melting pot, a pressure cylinder 10
and a plunger therein, and a charging chute com
municating between said melting pot and said
cylinder, the combination of a secondy plunger
carried by one of said blocks and movable into
and out of the discharge end vof said cylinder, 15
the pressure generated by said first-named plung
er being adapted to move said second plunger
outwardly with respect to said cylinder,‘and the
closing movement of said blocks being adapted
to move said second plunger at a point where 20
its end has cleared the entrance to said cavity,
means for resisting the outward movement of
said second plunger with respect to said cylinder,
means for adjustably regulating the extent of
such inward movement, a vacuum passage ter
of said cylinder, and a piston movable Lin said
passage for opening and closingl the latter, said
pistonV being also adapted to eject excess metal
from said chute back into said melting pot.
30
4l‘i. In a pressure casting machine of the type
combination of a vacuum passage terminating at
having separable die blocks defining a mold cav
ity, means for opening and closing said blocks,
a‘point in alignment with the upper end of said
a supporting base, and a pressure cylinder i'or
35 chute and adjacent the juncture of said chutev
and of said cylinder, and means for ejecting ex
cess metal from said chute back into said melt
ing pot.
,
10. In a pressure casting machine of the type
40 having a melting pot, a pressure cylinder and a
plunger therein, and a charging chute commu
nicating between said pot and said cylinder, the
combination of a vacuum passage terminating at
l the juncture oi' said chute and of said cylinder,
45 and a piston movable in said passage for open
ing and closing the latter, said piston being also
-adapted to eject excess metal from said chute
back into said melting pct.
1l. In a pressure casting machine of the type
50 having a melting pot, separable die blocks de
fining a mold cavity, means for opening and clos
ing said blocks, a melting pot,_a pressure cylin
der and a plunger therein, and a. charging chute
communicating between said pot and said cyl
55 inder, the combination of a vacuum passage ter
minating adjacent the juncture of said chute
and of `said cylinder, a piston movable in said
passage for opening and closing the latter, said
piston being also adapted to eject excess metal
from said chute back into said melting pot, and
means operable by .the movement of said die
blocks for actuating said piston.
l2. In ya pressure casting machine of the type
having a melting pot, separable die blocks de
65 ñning a mold cavity, means for opening and clos
ing said die blocks, a pressure cylinder and plung
er therein for discharging fluid metal into said
cavity, and a charging chute communicating be
tween said pot and said cylinder, the combina
70 tion of a sec-end plunger carried-by one of said
blocks and movable into and out of the dis
_ charge end of said cylinder, the pressure gen
erated by said first-named plunger being adapt
ed to move said second plunger outwardly with
respect to said cylinder, and the closing move
25
minating adjacent the juncture of said chute and
receiving and discharging iiuid metal into said
cavity, the‘combination of a plunger movable
into and out of the discharge end of said cyl
‘inder for varying the volume capacity thereof, the
outer end of said plunger being slidably sup
ported by one of said blocks, a shaft parallel to 40
said plunger, a second shaft having its axis nor
mal to said plunger and said first-named shaft,
rack and gear means connecting said second
named shaft to said plunger and said ñrst-narned
shaft whereby movement in one direction of said
plunger is- transmitted to movement in an oppo
site direction of said ñrst-named shaft, and fric
tion detent means slidably connecting said first
named shaft to said supporting base, and means
for adjustably regulating the position of said fric
tion detent means.
'
15, In a pressure casting machine of the class
wherein iluid metal is fed through one of a pair
of separable die blocks from a pressure chamber
carried bysaid one of the pair of die blocks, and
a _plunger in said chamber for discharging fluid
metal from said chamber under pressure, the
combination of means independent of said plung
er and carried by the other of said pair of die
blocks for varying the volume capacity of said 60
chamber.
`
t 16. In a, pressure casting machine of the class
wherein ñuid metal is fed through one of a pair
of separable die blocks from a pressure cham
ber carried by said one of the pair of die blocks,
and a` plunger in said chamber for discharging
ñuid metal frcmy said chamber under pressure,
the combination of means independent of said
Yplunger and movable Within the interior of said
chamber for resisting the discharge of metal 70
therefrom and also for varying the volume ca
pacity of said chamber, said means being car
ried by the other of said pair of 'die blocks.
NATHAN LESTER.
WILLIAM M. LESTER.
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