Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
Most indirect extrusion presses operate with a die attached to the free
end of the indirect stem, or with a loose die dropped into a horseshoe-like receiver
attached to the free end of the stem. In both cases, to make it easy to change the
die the stem is shifted laterally to a position out beyond one side of the press
frame. The die then is removed from the stem, changed, and the stem with a new
die attached to it is moved back into operating position. This rrlanner of changing
dies is shown in patent No. 4,103,529, wherein the direct stem and the die connected
to it are moved laterally together. The stem cannot be retracted far enough for
the die to be moved laterally away from it even if the two were not connected to
10 each other. With certain aluminum alloys the indirect stem is moved out of the side
of the press in order to be able to cIean the build-up of aluminurn behind the rim o~
the die attached to the stem. This cleaning of the die may be required after every
second, third or fourth extrusion.
On the other hand, the ideal die for use in indirect extruding is one that
is fully loose so that it can be handled like a durnmy block. A fully loose die is one
that is not attached to the indirect stem directly or indirectly. It has the advantage
o~ possessing a greater diameter for a larger single extrusion, or ior simultaneous
multiple extrusions. In addition, during extrusion such a fully loose die will move
without strain through the billet container and will not exert side fGrces on the
20 stem due to inaccurate alignment. ~Ithough it is known that in one indirect extrusion
press a iully loose die is exchanged by an arm that moves into and out of the press,
the arm and its operating mechanism add cost and require additional maintenance.
It is among the objects of this invention to provide an indirect extrusior,
press, in which a fully loose die can be moved out to the side of the press frame
independently of the indirect stem, and with which a new die can be placed i
position for quick exchange while extruding is taking place through the other die.
,,~
The -following description ancl the accompanying drawings will serve as
an illustratlon bu-t not as a limitation of this invention.
Fig. I is a horizontal section showing extrusion about to begin;
Fig. 2 is a vertical cross section taken on the line 11-11 of Fig. I;
Figs. 3, 4 and 5 are views similar to Fig. 1, showing the press in succeeding
steps of the extrusion operation;
Fig. 6 is a fragmentary horizontal section showing the replacement die
slide moved into position for travel in~o the press; and
Fig. 7 is a view similar to Fig. 1, but showing the replacement die in
10 operating position.
Referring to Figs. I and 2 of the drawings, a gate lock housing I mounted
in fixed position has a horizontal passage extending through it from front to back.
Disposed in the rear end of this passage is a tubular block 2 that is held in place by
a releasable gate lock. The gate lock can be formed from a pair of locking members
3 that are slidable horizontally toward and away from each other in guide ways
formed in the housing. The inner ends of the locking members project into a
peripheral recess 4 in the block. When the locking members are in locking position,
the block cannot be moved axially. The locking members may be moved into and out
of locking position by fluid pressure cylinders 5 rigidly mGunted in the housing and
20 supplied with hydraulic fluid in the customary manner.
Secured to the front end of the tubular block is a channel member 8
~hat extends Iorward out of the housing passage. Fastened to the front end of the
channel is a vertical member 9 that ex~ends down to the front end of a piston rod
~ ~ J ~ ~ J
10 extending back into a fluid pressure cylinder 11 rigidly mounted below the housing.
When the gate lock is released, the pis-ton rod cao rnove block 2 forward and back
in the housing passage.
Secured to the rear end of block 2 is a bolster 13 that has a central
passage through i~ aligned with the opening through the block. Rigidly mounted in
this bolster is the enlarged front end oi a tubular indirect-extrusion stem 14. The
bolster normally is housed in an opening through a die slide 15, Irom which the
bolster can be withdrawn when the gate lock is released. The die slide, which is
open at its top, engages the front of the gate lock housing and is slidable transversely
10 thereof on a llori~ontal track 16 secured to the front of the housing. Mounted in
the rear end of the die slide is a die holder 17 that encircles the stem and which can
be lifted out of the slide when desired.
~ ehind the exposed or rear end of stem 14 there is a billet container 19,
in the front end of which there is an extrusion die 20. Although the die engages
the rear end of the stem, it is a fully loose die because it is not connected to the
stem. ln the container, directly behind the die, there is a heated billet 21, the rear
end oE which is engaged by a dummy block 22. The container can be moved toward
- and away from the die slide in a well known manner. Behind the container there
are ram means $hat include a solid stem 23 that can be moved forward against the
20 dummy block and then through the container when the ram means are actuated in
the conventional way. While thls stem is extruding the billet through the die to
produce an extrusion 24 that passes forward through the indirect-extrusion stem and
the tubular means formed by the bolster and block and out of the front end of the
gate lock housing, the container moves forward around the stem as shown in Fig. 3.
At the conclusion of extrusion, the die, dummy block and extrusion butt 25 are in
the rear end of the container passage.
.~LJ~ J ~r~
As shown in Fig. 4, the gate lock then is opened and indirect stem 14
is pulled forward until the butt, which has been pushed out of the container by stem
23, is directly behind the die holder 17 in positjon to be cut off by a shear ~not
shown~. Moving the dummy bJock and butt forward caused the die to be pushed into
the die hoJder. The dummy bJock is received by a supporting member 2~ that has
been raised to support both it and the severed butt, which are then Jowered. The
passage of the dummy bJock through the container cJeans out the container passage.
The next step is to move the indirect stem farther forward in the gate
Jock housing, away from the die and die sJide, until the rear end of the stem is
10 entirely within the rear end of the housing passage. The die slide 15 then is ~ree to
be moved along track 16 transverseJy of the gate lock housing to a point beyond
one side of the housing as shown in Fig. 5. This movement of the slide can be
accomplished by any suitable means, but preferably by means of a fJuid pressure
cylinder Z8 projecting from one side of the gate lock housing, to which it is secured
at one end of the track. A piston rod 29 projects from the cylinder and is detachably
connected to the ad jacent side oI the slide, preferably through the medium of a
connecting member 30 attached to the piston rod and movable along the ~rack. As
shown in Fig. 2, this member is provided with a T-shape rib 31 that fits in a T-
shape slot in the adjoining side of the die slide. The slot extends from front to back
20 of the die slide. When the piston rod is extended, the connecting member 30 pushes
the slide and die out to one side of the housing and onto a receiving table 32. The
die slide ~hen can be disconnected from the connecting member by moving the table
rearwardly on its track 33. At the same time, as shown in Fi~. 6, a similar die slide
34 containing a die holder and a die 35 can be moved by the table into engagement
with connecting member 30 and then pulled back by the piston rod to operative
position between the gate lock housing passage and the billet container as shown
in Fig. 7. This is a quick and simple way to change dies. If it is not desired to
o~
change the dies but merely to clean a die, the die can be removed from die holder
17 and die slide 15 on table 32, cleaned and then replaced.
W ith the extrusion press described herein, the fluid pressure cylinders
can be programmed by an electrical systern to operate at predetermined intervals
in the proper sequence so that changing of the die is performed automaticalJy at
regular intervals. The control system is not part of this invention and is not claimed
herein, but the construction of the press lends itself to such automatic operation.
According to the provisions of the patent statutes, I have explained the
principle of my invention and have illustrated and described what I now consider to
10 represent its best ernbodiment. However~ I desire to have it understood that, within
the scope of the appended claims, the invention may be practiced otherwise than
as specifically illustrated and described.