Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention relates to die casting machines and
in particular a machine of the type for producing precision
die casti~ngs with a compact toggle mechanism providing a
clamping force in excess of 20 tons.
The die casting machine according to the present
invention provides several important improvements in the art
including a nozzle and gooseneck which move on a direct path
toward and away from the parting line of the dies as well as
a double toggle arrangement for the dies and their carriers
to provide an extremely high clamping force for a machine of
its size. A novel valve arrangement in the gooseneck provides
a rapid and efficient manner in providing molten zinc to the
die cavity.
According to one aspect, the present invention
relates to a die casting machine comprising in combination,
a frame supporting a base plate and a metal melting pot; a
die guide mounted on the front of said base plate; double
locking toggle means for actuating dies and cores in said
guide; a gooseneck assembly, including a passageway, mounted
on the melting pot and including pump means for filling a
pump chamber in the gooseneck and for making a shot ~hrough
the gooseneck passageway into the cavity of said dies; a gate
member for selectively directing molten metal from the pot `
into the chamber or from the chamber into the die cavity
responsive to movement of the pump; and means for effecting
linear movement of said gooseneck and nozzle toward and
away from the parting line of said dies; said toggle means
comprising a yoke member mounted to said base plate adjacent
the end of each die gui~de and a link assembly for connecting
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an actuator to the carrier of the die in the die guide; said
link assembly comprising first and second links connecting
the die carrier to the yoke assembly; a beIl crank pivotally
mounted on said yoke and having one end pivotally secured to
said actuator and its other end similarly secured to the
juncture of the first and second link members by way of a
third link member.
The invention is illustrated by way of example in
the accompanying drawings in which:
Figure 1 is a partial cross-section of the die
casting machine according to the present invention;
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Figure 2 is a view of the rear portion of the base
plate as viewed through the line 2-2 in Figure l;
Figure 3 is a cross-sectional view taken generally
along the line 3-3 of Figure l;
Figure 4 is a frontal view of a portion of the
machine showing the die guide and one of the toggle mechanisms
for actuating the dies in the guide, the toggle mechanism as
shown in the open position;
Figure 5 is a cross-sectional view taken along the
line 5-5 in Figure 4; and
Figure 6 is a view similar to Figure 5 but showing the
toggles with the die carrier in a closed position.
Referring to Figure 1, the die casting machine
illustrated generally at 10 comprises a frame member 12
(shown only partially) supporting a base plate 14 of
~ substantial thickness through a pivotal mounting 16 to the
: frame 12 adjacent the forward end thereof and by angular
struts 18 extending from the rear part of the frame up to a
supporting position on the rear of the base plate 14. The
latter supports on its front face a multi-slide die guide 20
detachably secured to the plate 14, the die guide including
a detachable cover 22 and incorporating a plurality of slide-
ways 24 for the die carriers 26. As seen in Figure 1, the
die guide 20 is concentrically positioned over a large aperture
28 in the base plate 14 to allow communication between the
dies and the nozzle of the gooseneck in a manner hereinafter
described.
A frame member 30 supports a furnace pot 32 for
melting and containing a casting metal such as zinc, the level
of which is indicated by a phantom line 34. The interior of
the pot 32 is maintained at a desired temperature by a
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plurality of electric cartridge heaters 36 positioned
throughout the side walls and bottom wall of the pot as
indicated in Figures 1 and 3. The upper edges 38 of the
side walls of the pot 32 are provided with support surfaces
40 for mounting a gooseneck assembly shown generally at 8 in
Figures 1 and 3. In this regard, the gooseneck assembly 8
has a central web 42 and side members 44 with a shaft 46
running therethrough, the ends of shaft 46 being pivotally
mounted in journal bearings 48. Cap screws 50 acting
through captive nuts 52 serve to adjust the attitude of the
gooseneck 8 with respect to the central shaft 46 for vertical
alignment of the nozzle 54 relative to the cavity in the dies.
Bearings 48 also include integral bearings 56 for
mounting the gooseneck 8 for linear movement along shafts 58
mounted at each of their ends in journal blocks 60 which in
turn are secured by cap screws 62 to the upper surfaces 40
of the side walls of the pot 32. It will be appreciated from
Figure 1 that the longitudinal axis 64 of the shafts 58 are
parallel to the center line 66 of the nozzle 54 so that
movement of the gooseneck 8 along the shafts 58 will move
the assembly including the nozzle 54 toward and away from the
dies in a straight, linear manner.
Means for effecting the movement of the gooseneck is
seen in Figures 1 and 2 where a linear actuator 68 is
pivotally secured to the upper end of the rear surface of the
base plate 14 through mounting plate 70 or the like. The
other end of the actuator 68 is coupled by way of a roll pin
72 to one arm 74 of a bell crank 76. This member is pivotally
mounted by shaft 80 to journal blocks 82 detachably secured
to the back of the base plate 14 on either side of the central
aperture 28 therein. The bell crank 76 has two other extending
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arms 84 having elongated apertures 86 therein for receiving
a shaft 88 which is mounted transversely in the upper end of
the gooseneck proper 90.
It will be appreciated from Figure 1 that operation
of the actuator 68 in the direction of arrow 92 will pivot
the bell crank 76 so that by virtue of its connection with the
gooseneck 90 through the pin 88, the complete gooseneck
assembly 8 will be moved rearwardly along the shafts 58,
drawing the nozzle 54 directly back from its Figure 1 position
where it engages the dies at the parting line thereof.
Operation of the actuator in the opposite direction, in the
direction of arrow 94, pivots the bell crank 76 in the opposite
direction to move the complete assembly 8 to the left in
Figure 1 and to bring the nozzle 54 up against the parting
line of the dies, the pressure in the actuator 68 maintaining
the nozzle in its operative position.
The gooseneck 90 includes a pump chamber 96
communicating with the nozzle 54 by way of a passageway 98
through a gate valve 100. It will be seen from Figure 1 that
gate valve 100 is provided with an actuator 102 and connected ;~
thereto by a shaft 104. Also supported by the web 42 of the
assembly 8 is a further actuator 106 which is connected by a
shaft 108 to piston pump 110 mounted in the top of the pump
chamber 96. Gate valve 102 has two apertures therein, the
first aperture 112 providing communication between the pump
chamber 96 and the interior of the furnace pot 32 and the other
aperture 114 providing communication between the chamber 96
and the nozzle 54 through the passageway 98, when the gate
valve is moved to its lower position, not shown. In operation,
the gate 100 is closed as shown in Figure 1 opening the
aperture or channel 112 to the interior of the pot 32 and the
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piston pump 110 is drawn upwardly by the actuator 1~6_to fill
the chamber 96. The gate 100 is lowered by the actuator 102
and shaft 104 so that the aperture 114 is in line with the
passageway 98 and a shot is made by the piston pump 110 through
the nozzle to fill the cavities in the dies. When the
pressure is such that the cavity has been filled, the gate 100
is raised and the excess pressure from the piston pump 110 is
exhausted into the pot via the channel 112. When the gate is
in its raised position of Figure 1 the gooseneck passageway 98
is full of molten casting metal, the gate 100 blocking the
metal from draining back toward the chamber 96. The pump 110
is then again drawn upwardly to fill the chamber 96, thus
completing the cycle.
Referring to Figure 4, the die guide 20 is secured to
the base plate 14 by bolts 116 and the top 22 is secured to
member 20 by cap screws 118. The guide 20 is provided with a
plurality of guide ways 26 each of which is adapted to receive
a carrier 120 for a die member 122 as shown in Figure 5.
The dies 122 are actuated to open and closed positions
by means of an actuator 124 which is supported for operation by
a yoke member 126. The latter provides support for the actuator
and for the linkage between the operative end of the actuator
and the die carrier 120. In Figures 4 and 5, the linkages and
die carriers are shown in the open position and as shown in
Figure 5, a first link 128 is pivoted by means of a roll pin
130 to the yoke 126 and at its other end, first link 128 is
similarly connected by way of a pin 132 to a second link 134,
the other end of which is pivotally connected by a pin 136 to
the end of the die carrier 120. A third link, 138 interconnects
pin 132 with one end of a bell crank 140, the other end thereof
being pivotally connected at 142 to the operative end of the
actuator 124. The central portion of the bell crank is pivoted
through a pin 144 to a wing of the yoke 126.
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Referring to Figure 6, it will be seen that the
actuator 124 has been operated to d:raw its piston end inwardly
to swing the bell crank 140 so that the first and second links
128, 134 are brought into linear alignment with one another
thereby driving the carrier 120 and its die 122 to the closed
position, the third link 138 serving to lock the first and
second links in place, the pivot points 142, 132 as well as
the pivot 146 lying in alignment with one another and at 90
to the pivot pins connecting the first and second links.
It will be appreciated that the present invention
provides a die casting machine with a novel toggle arrangement
which gives it double locking provision to the die carrying
shanks. The die carrying base plate 20, while illustrated in
Figures 4, 5 and 6 with a single shank 120 and die 122 thereon
can provide three additional slideways 26 as shown in Figure 4 ~ :
and a fifth position normal to the plane of operation of the
shanks 120 and mounted centrally in the opening 150 as shown
in Figure 4. Accordingly, the machine may provide five
slideways at 90 to each other in any combination and any
one of these slideways would have the capacity of retracting
fine cores before the mold openings or to maintain the ejector
mechanism fixed during the opening of the mold sections and
to release the molding at any location of the mold opening
stroke. :
While the present invention has been described in
connection with a specific embodiment thereof and then a
specific use, it will be appreciated that various modifications
thereof will occur to those skilled in the art without
departing from the spirit and scope of the invention as set
forth in the appended claims.
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The terms and expressions which have been employed in
this application are used as terms of description and not of
limitation and there is no intention in the use of terms and
expressions to exclude any equivalents of the features shown
and described or portions thereof, but it is recognized that
various modifications are possible within the scope of the
invention claims.
