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Патент USA US2128152

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Aug. 23, 1938.’
>
H. F. MacMlLLlN
2,128,152
AUXILIARY-HYDRAULIC DEVICE FOR PRESSES
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Filed Aug. 16, 1934
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A TTORA/EYS
Aug. 23, 1938.
H. F. MacMlLLlN
2,128,152
AUXILIARY HYDRAULIC DEVICE FOR PRESSES
Filed Aug. 16, 1954 '
5 Sheets-Sheet 2
8
32 ‘
34
By
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40
2 34
32
Aug. 23, 1938.
2,128,152
H. F. MaOMILLIN
AUXILIARY_HYDRAULIC DEVICE FOR PRESSES
Filed Aug.‘ 16, 1954
5 Sheets-Sheet 5
27
W
5
Aug. 23, 1938-
2,128,152
H. F. Mac‘MILLIN
AUXILIARY HYDRAULIC DEVICE FOR PRESSES
' Filed Aug. 16, 1954
5 Sheets-Sheet 5
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M/Vf/VTOR
#014491?” I‘: MAGM/lLl/V.
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ATTORNEYS
Patented Aug. 23, 1938
. 27,128,152
UNITED STATES PATENT. OFFICE
AUXILIARY HYDRAULIC vDEVIOE FOR
‘
PRESSES
Howard F. MacMiilin, Mount Gilead-Ohio, as
signor, by ‘memo assignments, to The Hydrau
lic Press Corporation, Inc., Wilmington, Del.,
a corporation of Delaware
'.
Application August __16, 1934, Serial Ne. 740,148
10 Claims. (or. loo-Jo)
the auxiliary pressing cylinder located in the bed
This invention relates to :presses, and espe
of the press instead of in the platen; ‘
cially to those having theirj"platens moved by
non-hydraulic means.
i
'
Figure 6 is a diagrammatic view of a circuit
whereby the pressing ram in Figure 4 may be
'
One object of my invention is to provide a
Ci press having a platen moved»; by any convenient
means whether hydraulic or ‘non-hydraulic‘, and
lifted with the assistance of an external source
of pressure, such as air;
Figure 7 is a front elevation partly in section
of a hydraulic circuit whereby the press may be
given a. two-stage-eifect‘ through a booster action
devices for generating ?uid pressure operated by
the motion of the platen, the fluid pressure thus
generated being available for operating various
contributed by the generator pistons;
hydraulically-actuated devices, and/or provid
10
Figure 8 is a vertical section through a pilot
ing pressure control.
Another object is to provide, in a press operated operated check valve ‘(employed in the present
by non-hydraulic mechanism, means for giving .
the press a hydraulic effect and hydraulic'pres
’ Press with single-acting generator rams
circuit.
'
sure control.
’
'
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-.
Refe'rring to’the‘drawings; in ‘detail, Figure 1
Another object is to provide a press having a
shows a. press havinsi‘ia, base 1| Joined" by side _ ~
mechanically-operated platenwith hydraulic de
vices soconnected that the motion of the platen
members 2 to the top'niember 8, asby'the strain, .
causes these devices to generate ?uid pressure,
rods 4 on which are .threadedithe nuts 5‘. .Mount4;26
this being \utilized to actuate an.‘ auxiliary hy
ed on the base I ma work table or bed 8.,
draulic ram for-exerting a hydraulic effect and
giving a pressure control upon the work pieces,
with ‘guide portions 1‘ adaptedto receive a press
with the speed of a mechanical press. '
'
The side members" 2:: of the press are equipped v
platen 8 for longitudinal reciprocation. The
‘keeping of the platen 8 in engagement with the
‘
Another objectis to provide a press having
a platen, movable by whatever means, with de
vices attached thereto for generating ?uid pres
guide portion 1 is assisted by the ‘retaining plates‘v _
9 bolted to the side. members 2 of the press. ,1 __
The press platen 8 may be movedin any con
operated by this fluid pressure and adapted to vvenient manner, such as mechanically .or hy
give‘ a pressure-controlled pressing effect: this, draulically. For purposes of illustration,‘ a gear- ' 30v
auxiliary hydraulic ram being located in any driven mechanical crank press is shown, but
desired place,’such as in the platen or‘the bed other types may be used without departing from
sure, together with an auxiliary hydraulic ram
of the press.
-
the scope of my invention.
'
Another object is to provide a platen-operated
hydraulic generating arrangement of the above
mentioned type, the auxiliary hydraulic ram and
the hydraulic generator rams being of a double¢
acting nature so that the upward motion of the
main platen retracts the auxiliary hydraulic ram.
In the drawings:
4O
Figure 1 is a front elevation, partly in section,
of a press embodying single-acting hydraulic
generator rams and a single-acting auxiliary hy
draulic
ram;
,
’
'
Figure 2 is a side elevation of the press shown
in Figure 1, partly in section, along the line 2—2
of Figure 1;
~
Figure 3 is a horizontal section'along the line
3-3 ‘of Figure 1;
'
Figure 4 is a front elevation, partly in section,
of a portion of the press shown in Figure 1, but
illustrating the use of double-acting generator
rams in connection with a double-acting auxiliary
hydraulic ram;
65
Figure 5 is a View similar to Figure 1, but with
:
‘In the form of. press shown, ‘the platen 8 is
provided with a cross shaft l0 journaled in bear
35
ings _II on the upper portion of the platen 8.
Pivotally engaging the cross shaft I0 of the '
platen 8 is a connecting rod I! having a lower
bearing l3, surrounding the cross shaft l0. At
its upper end, the connecting rod I2 is provided
with an upper bearing I4, which surrounds the 40
crank portion ii of the main drive shaft vIii.
The latter is journaled in bearings I1, mounted
upon the side members 2 of the press.
The driving end of the main drive shaft I6 is
provided with a gear l8 for this purpose. The 45
gear I8 is ‘connected by a clutch mechanism with
in the clutch housing IS in such a manner that
the gear l8 may be connected or disconnected
from the main drive shaft I6, as desired. The
clutch mechanism within the clutch housing I9 is 50
actuated by the crank arm 20 mounted on the
clutch shaft 2| and connected by the link 22 to
the pedal rod 23. The latter is reciprocably
supported in ‘the bosses 24 attached to. one of the »
side members 2, and is secured at its lower end 65
» -
2
2,313,102
by the pivotal connection 25 to the foot pedal 25.
By depressing or releasing the foot- pedal 28, the
downwardly. Thus the auxiliary pressing ram
38 is a positive-acting hydraulic‘ plungerwwhich
gear l8 may be made to operatively engage the‘ - performs actual pressing work by ,moving3 posi
main drive'shaft It, or rotate loosely-upon it.
in this manner, the foot pedal 28.controls the
press to provide for its executing working strokes
or for its remaining idle, as may be desired.
'
The gear I8 is driven by a pinion 21, meshing
therewith, and mounted upon the countershaft
10 28, journaled in the bearings 28 attached to the
side members 2. The Opposite end of the coun
tershaft 28 from the pinion 21 bearslf'a ?ywheel
38 and a pulley 31, whereby the press maybe
drivenfas from an electric motor belted to this
pulley. Accordingly, when the pulley 3| is thus
rotated, the gear- l8 also rotates loosely upon the
main drive shaft It. When the foot pedal 28 is '
depressed, the gear 18 drivingly engages the main
shaft l8 and ‘causes the crank portion 15 thereof
20 to move in an orbital path. This movement causes
the connecting rod l2 to move up and down, car
rying with it the platen 8.
.
tively forward against the load, rather than a
mere cushioning device which recedesunder the
load.
‘
/
The pressure regulating valve 81 is so loaded
as to discharge ?uid from line 88 into line 88
during the working stroke, when a predetermined .
pressure is reached in the space above the aux 10
iliary pressing ram head 48. On thezupward or
return stroke of the press, the check valve .88/per
mits this discharged ?uid to be returned from the
make-up tank 82 to the lines~88 by way of the
vlines 8| and 88' and the pressure regulating valve 15
81. A similar action occurs with the press shown"
in Figure 4.
'
~
-
As the auxiliary pressing ram 38 moves down
wardly relative to the platen 8, it compresses the
coil spring 42. When the platen 8 starts on its 20
upward or return stroke, the generator cylinder
bores 32 move upwardly relative to the stationary
The platen 8 in its lower portion is provided
with a pair of generator cylinder bores 32, and an
?uid from the auxiliary pressing cylinder 33. The '
auxiliary pressing cylinder bore 33. These cyl
energy stored in the compressed coil spring 42
inder bores are connected at their upper ends
then comes into play to retract the auxiliary
pressing ram 38 by forcing it upwardly into its
by the passages 34. Reciprocably mounted within
the cylinder bores‘ 32 are hydraulic generator
rams 35, having their lower ends-secured in sock30 ets 36 in the base I (Figure 1). Leakage from
the generator cylinders 32 is prevented by the
provision of the packings 31, adapted to be com
pressed by glands 38.
I
'
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generator rams 35, thus releasingthe pressure
normal position of rest.
_
v Press with double-acting pressure generating,
rwms and auxiliary pressing rams
'
80
In Figure 4 a double-acting auxiliiary pressing
ram 45 is shown as being served by the double
Mounted for reciprocation in the auxiliary acting pressure generating rams 48. The latter
pressing cylinder bore 33 is the auxiliary pressing have enlarged piston heads 41 upon theirupper
ram 38, having an upper'enlargjed portion 48 _ ends,‘ and also have longitudinal bores 85 as in
and a lower reduced portion 4|. Surrounding the Figure 1. The pressure generating cylinder bores,
reduced portion 4| is a coil spring 42, which is the auxiliary pressing cylinder bore, the packing
engaged by the enlarged head 48, thus providing glands, and the remainder of the hydraulic cir
for retraction of the auxiliary pressing ram 39,
cuit remain the same as in Figure 1,- hence are 40
' when the platen 8 moves upward. Leakage ‘from > ' designated by the same numerals. The regulation
the cylinder bore 33 is prevented by the packing
43, engaged by the gland 44, which surrounds the
reduced . portion 41 of the auxiliary pressing
ram 39.
‘
v
To regulate the pressure developed in the oper
ation of the press, as well as to replenish the
?uid required, the generator plungers 35 are pro
’ vided with longitudinal bores 85 which communi
50 cate by the pipe lines 88 with the pressure regu
lating valve 81. In the present embodiment
(Figure 1) this valve is preferably of the type
shown in the copending application of Ernst,
Serial No. 669,493, now Patent No. 2,086,295, dated
r July 6, 1937. Connected to the opposite side of
the pressure regulating valve 8,1 by the line 88
is the check valve 88, which permits ?uid to pass
through itself toward the pressure regulating
valve 81, but not in the opposite direction, The
pipe lines 88 and 81 run from the remaining ports
respectively of the pressure regulating valve 81
and check valve 88 to the “make-up" tank 82. '
and replenishment circuit is as in Figure 1.
The auxiliary pressing ram 45. (Figure 4) is pro
vided with an enlarged head 48 and a reduced
stem 48. The cylinder bores 32 and 33 are con 45
nected above the enlarged head 48‘ by the upper
passages 58; and below the enlarged head 48
by the lower passages 5|. The latter also are
located below the lowermost positions of the in
tensl?er piston heads 41.
r
l
I
50'
In the operation of the arrangement shown in
Figure 4, as the platen 8 descends, the down~
wardly moving cylinder bores 32 cause the" ?uid
to be placed under- pressure by their engagement
with the fixed pressure generating piston, heads 65
41. .This pressure ?uid is forced through the
upper passages 58 into the auxiliary pressing bore
33, causing the auxiliary pressing ram 45 to move
downwardly and forwardly against the load, thus
positively exerting its force upon the work piece. 60
When the platen 8 has completed its working
stroke and starts its return stroke, the intensii
The latter contains ?uid under a low pressure,
such as under a gravity head or low air pressure,
?er cylinder bores 32 move upwardly relative to
and supplies replenishment ?uid to the generator
the enlarged head 48 of the auxiliary pressing 65
cylinders 32, in the manner described below. A
similar arrangement is used with the press shown
the intensi?er piston heads 41.
The ?uid above '
In operation, when the foot pedal 26 is de
70 pressed and the platen 8 moves downwardly, ?uid
ram 451s thus drawn into the space above the
pressure generating piston heads 41. At the same
time, the ?uid entrapped below the intensifier
piston heads 41 is forced outward through the 70
'75 causing the‘ auxiliary pressing ram 38 to'move
regulating valve 81 and the replenishment cir 75
,
in Figure 4.
'
lower passages 5| into the space beneath the en
under pressure by the stationary generator rams ‘,larged head 48 of the auxiliary pressing ramr45.
This causes the head 48 to rise, retracting the aux
' 35. _This pressure ?uid moves through the pas
,sages‘ 34 into the-auxiliary pressing cylinder 33, I iliary pressing ram 45. The action‘ of the‘pressure
within the generator cylinder bores 32‘ is placed
2,198,152
cult is the same as previously described for Fig
3.
member 3, ‘and has a yoke 11 \at‘its lower end
with a roller 12 which serves as a cam follower,
ure 1.
'
‘It will be‘further understood, from'Figure 6,v engaging the cam 13 ‘mounted upon\the main
that the pressing plunger ‘48 of Figure 4 may be drive shaft I6 of the press. The coil s?‘ing 14 5
retracted by means of pressure applied to the ' urges the carnwfollower 12 downwardly against\
.
replenishment ?uid in the make-up tank .92, the the cam 13.
The 'pilot—operated check valve 95 shown in
plunger 46 being provided with the twin longi
tudinal bores I23 and in opening ‘respectively Figure 8 may be of any conventional type, the
into the space above and beneath the piston head details of which form no part of the‘ present in 10
41. The pressure regulating valve 81 and the vention. The check valve shown for purposes of
check valve 89 are similar in construction and illustration consists of a casing I50 having
threaded connections I5I and I52 to the pipes
operation to those in Figure 4. The ?uid in the 99
and 91, respectively. The casing I50 is pro
make-up tank 92 (Figure 6) is subjected, as by
vided
with a partition I53 with a valve‘ seat I54
compressed air, to pressure high enough to bal
engaged by a valve member I55‘, mounted on the 15
15 ance the weight of the hydraulic pressing ram 49.
It will be further understood that the auxiliary end of a valve rod I56. The latter passes through
pressing ram may be placed in the press bed, as
in Figure 5, instead of in the platen.
'
Press with two-stage effect from external 'circuit
20
and generator rams
The press arranged according to the circuit
shown in Figure 7 provides a two-stage effect.
To accomplish this, the hydraulic pump 64 pro
- vides ?uid to advance the pressing ram 49 rapidly
until an intermediate pressure is reached, after
which ‘the hydraulic generating plunger 51 im
parts such pressure to the ?uid as to ?nish the
coil spring I6I of a pressure su?lcient to over
come the action of gravity and tending to urge
the valve member I55 lightly into engagement
with the valve seat I54. Opening into the bore
I 59 is a port I62 leading to a longitudinal groove
I63,‘which in turn, opens into a chamber I64
formed between the connecting casing I65 and
the plug. I66, closing the bore I59 and engaging
the end of the coil spring I6I. The casing con
nection I65 is threaded, as at I61, to a portion 30
of the casing I50 and has a passageway I68 lead
with a high pressure regulating valve 93 and a
pilot-actuated pump unloading valve 94 of any ing therefrom into the pipe I03. 3
In the operation of the circuit shown in Fig
suitable patterns, the types shown being those
disclosed in the copending application of Ernst, _ ure '1, and during the working stroke, the line 60
Serial No. 669,493, .now Patent No. 2,086,295, from the pump 64 delivers ?uid under pressure
dated July 6, 1937. Between these is arranged a through the valves 94, Hand 93 and by way of
operation at a higher pressure level.
30
a bore I51 in the casing I50, into a valve-lifting '
chamber I58 having a cylinder bore I59. Secured
to the opposite end of the rod I56 from the valve
member I55 is a piston head-I60, engaged by a
,
To this end (Figure '1) the circult'is provided
‘the lines 99, 91 and 96 to and throughthe plunger
opening plunger operated by ?uid reaching it 51 and the cylinder 53 to the space above the
through the line I03 and normally permitting ‘ pressing plungerllil.v The latter is forced down
?uid to go from valve 9.4 to valve 93, but forcibly wardly onto the work piece until?the pressure
opened under certain circumstances, hereinafter builds up to such an extent that it backs up in ,
described, to permit ‘?uid to go in the opposite the pilot line 98 and- operates the pilot plunger
direction. This check valve 95 may be of any of the pump unloading valve 94, thenceforth
conventional type, the type shown being described causing the line 60 from the pump 64 to dis
charge its contents into the discharge lines IM
in more detail below.‘
and I02, thence into-the tank 84! The further
Y From the bore 59 of the generator piston 51,
pilot-operated check valve 95 having a valve
the line 96 leads to one side of the high pressure
regulating valve93, from the opposite side of
which the line '91 leads to the check valve 95 and
50 the pilot line 98 leads to the pilot port of the
pump unloading valve 94. From the opposite side
of the check valve 95,‘the line 99 leads to a main
chamber port of the pump unloading valve 94, to
the opposite side of which is connected. the line
60 from the pump 64, ‘From the discharge ports
> of the valves 93 and 94 run the discharge lines
motion of the press'platen 8' then causes the
generating plunger 51 to continue to buildup the
pressure of the ?uid and thereby to force the
pressing- plunger still further forward. When the
50
pressure of the ?uid exceedsthe load setting of
the high pressure regulating valve 93 it actuates
the latter. causing it to discharge‘ the ?uid from
the line 96 into the discharge line I00 and thence
bv the line I02 into the ,tank 84 until the work
ing stroke of the platen 8 has been completed.
The platen 8 then starts its return stroke,
I00 and IM respectively, joining the common dis;
charge line I02 which runs back to the supply ,\ whereupon the ?ow from the pump 64 is reversed
by the action of the cam' 13. The fluid under 60
tank“.
To complete the'circuit, the line 6| from the pressure now passes through the line 6_I, the
(30.
opposite side of the pump 64 is connected to they . plunger 58 and the cylinder 52 into ‘the space
bore 59 of the plunger 56, whence a pilot branch beneath the pressing plunger head 48. retracting
I03 continues onward to the pilot port of the
the latter. , Meanwhile the same ?uid under pres
check valve 95.
sure backs up in the pilot line I03 to the check
-
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.The pipes 60 and 6| lead to the opposite ports
62 and 63, respectively, of thehydraulic pump 64.
The latter is of a variable delivery type having a
?ow-control rod. 65, which when moved in or out,
varies the quantity and direction of the pressure
?uid passing through the pipes 60 and 6I. The
?ow-control rod 65 is connected by the link 66
to one arm of the bell-crank 61, the other arm
thereof being connected by the link 68 to the cam'
push rod 69. This rod 69 is reciprocably mounted
75 in the bearings 10, attached to the upper frame
valve 95, entering the bore I59 (Figure 8) and
urging the piston head I60 outwardly against the
urge of the spring I6I, thereby opening the check
valve 95 by forcibly lifting the valve member I55
from its seat I54.
This allows-the ?uid from the _
space above the pressing plunger head 48 to pass
through the plunger 51; the lines 96, '91 and 99;‘
and the valves 93, 95 and 94 to the line 60, thence _
back to the pump 64._ This cycle of operations
repeats itself as. theplaten 8 reaches, its, limits
1.5
4
2,128,152
of travel during its subsequent working‘ and re
turn strokes.
-
It will be further'unders'tood that the auxiliary
pressing ram 39 might be‘ placed in the bed 8
instead of in the platen 8, the intensi?er rams
then being carried by the platen. This arrange
ment is shown in Figure 5.
@Having thus fully described my invention, what
I claim as new and desire to secure by Letters
10 Patent is:
"
1. In combination in a press, a movable platen,
a piston-and-cylinder assembly including a piston
member and a cylinder member for generating
?uid pressure operated by the motion of said.
15 platen, one of said members being associated with
said movable platen and the other member being
mounted in a substantially stationary position
relative thereto, and a second piston-and-cylinder
assembly adapted to be operated by the ?uid from
20 said press-operated means, said second piston
and-cylinder assembly being arranged to provide
additional pressing movement to that of said
platen.
,
2. In combination in a press, a movable platen,
a frame having a bed, means for generating ‘?uid
pressure operated by the motion of said platen,
and a piston-and-cylinder assembly adapted to
be operated, by the ?uid pressure from said plat
en-operated means, said piston-and-cylinder as
30 sembly being arranged between said platen and
said bed to provide additional pressing movement
to the pressing movement of said platen.
_3. In combination in a press, a movable ‘platen,
a frame, a cylinder bore within said platen, a
b3 GI
plunger reciprocable within said cylinder bore
and secured to said frame, said plunger being» ar
ranged to oppose the motion of said platen and
to compress the ?uid within said bore, and a
40
hydraulically-actuated device adapted to be op
erated by the ?uid pressure generated by reason
of the relative motion between said cylinder bore
and said plunger.
4. In combination in a press, a movable platen,
a frame, a pressure-generating piston-and-cylin
der assembly including a,_ piston member and a
cylinder member operated by the motion of said
- platen, one of said members being associated with
said movable platen and the other member being
secured to said frame in a substantially station
00 ary position relative to said platen-associated
_member and a second piston-and-cylinder assem
bly mounted‘ on said platen and adapted'to be
operated.relatively to said platen by the ?uid
pressure from said platen-operated piston-and‘
in u cylinder assembly by reason of the relative motion
between said platen and said frame.
5. In combination in a press, a movable platen,
a frame, a presure-generating piston-and-cylin
der assembly operated by the motidn of said plat
en, the'cylinder of said assembly being associated
platen, one of said members being associated with
said movable platen and the other member being
secured to said frame in a substantially station
ary , position relative to said platen-associated
member, a second pistonrand-cylinder assembly
adapted to be operated by the ?uid pressure from
said pressure-generating piston-and-cylinder as
sembly by reason of the relative motion between
said platen and said frame, said second piston
and-cylinder assembly being arranged to provide 10
additional pressing movement to the pressing
movement of said platen, an external source of
?uid connected to replenish the ?uid in said as
, semblies, and pressure-responsive means adapted
to relieve the ?uid pressure in said assemblies 15
when it exceeds a predetermined pressure.
. 7. In combination in a press, a’movable platen,
a frame, a pressure-generating piston-and-cylin
der assembly including a piston member and a
cylinder member operated by the motion of said 20
platen, one of said members being associated with
said movable» platen and the other member being
secured to said frame in a substantially station
ary position relative to said platen-associated
member, a second piston-and-cylinder assembly 25
adapted to beoperated by the ?uid pressure from
said pressure-generating piston-and-cylinder as
sembiy by reason of the relative motion between
said platen and said-frame, said second ston
and-cylinder assembly being arranged to provide
30
additional pressing movement to‘ the pressing
movement of said platen, an external source of
?uid connected to replenish the ?uid in said as—
semblies, pressure-responsive means connected to
said source and adapted to discharge the excessive
?uid pressure from said assemblies into said
Cl
source when it exceeds a predetermined pressure,
and means enabling the ?ow of liquid in one'di
rection only between said assemblies and said
source..
'
40
8. In combination in a press, amovable platen,
a double-acting pressure-generating piston-and
,cylinder assembly operated by the motion of said
platen, and a second double-acting piston-and
cylinder assembly adapted to be operated by ?uid 45
pressure from said pressure-generating assembly.
9. In combination in a press, a movable platen, .
a double-acting pressure-generating piston-and
cylinder assembly operated by the motion of said
platen, said assembly including a piston member
anda cylinder member, oneof said members be 50
ing associated with said movable platen and the
other member being mounted in a substantially
stationary position relative thereto, and a second
double-acting piston-and-cylinder assembly asso
ciated with said movable platen and adapted
be operated by ?uid pressure from said pressure
generating assembly.
10. In combination in a press, a frame, a mov
able platen movably mounted on said frame, a
with said movable platen and the piston thereof ' ‘pressure-generating piston-and-cylinder assem 60
being substantially immovably securedto said , bly connected between said platen and said frame .
frame and a second piston-and-cylinder assembly _ and adapted to be operated by the motion of said
adapted to be operated by the ?uid pressure from platen, a second piston-and-cylinder assembly
.- said platen-operated piston-and-cylinder assem
bly by reason of the relative motion between said
platen andsaid frame, said second piston-and
' cylinder assembly being arranged to provide addi
, adapted'to be operated by ?uid pressure from said
pressure-generating piston-and-cylinder assem
bly by reason of the relative motion between said
platen and said frame, and means to retract the
65
tional pressing movement to the pressing'move I piston of said‘ second piston-and-cylinder assem
'
bly during the returnstroke of said platen, said
70 ment of said platen.
6. In combination in a press‘, a movable platen, retracting means comprising a source of pneu 70
a frame, a pressure-generating piston-,and-cylin
matic pressure operatively connected to said pis
der assemblyincluding a‘v piston member and a ton of said second piston-and-cylinder assembly.
cylinder member operated by the motion of said
HOWARD F. MACMILLIN.
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