MACHINE DE MOULAGE PAR INJECTION

INJECTION MOULDING MACHINE

Abrégé anglais

An injection moulding machine comprising a machine
frame (1), a stationary and a movable mould mounting
plate (2, 8) and a cylinder plate (3) carrying at least
one piston-cylinder unit (7) of a hydraulic or
electromechanical closing mechanism. The cylinder plate
(3) at which the movable mould mounting plate (8) is
supported and the stationary mould mounting plate (4)
are connected without struts exclusively by way of the
machine frame (1). The closing force which occurs
during the injection operation and the expansion force
between the cylinder plate (3) and the mould mounting
plate (2) are only passed by way of the machine frame
(1). One of the mould mounting plates (2, 8),
preferably the movable mould mounting plate (8), is
mounted tiltably about a horizontal axis.

Revendications

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An injection moulding machine comprising a machine
frame, a stationary mould mounting plate carried by said frame,
and a movable mould mounting plate driven by a hydraulic or
electromechanical closing mechanism, wherein said movable mould
mounting plate is mounted to be tiltable about a horizontal axis
to assume a position parallel to the stationary mould mounting
plate when the closing force is applied.
2. An injection moulding machine according to claim 1
wherein said horizontal axis is formed by a pivot joint in said
closing mechanism.
3. An injection moulding machine according to claim 2
including an adjustable stop provided above the pivot joint
between the two members of said pivot joint.
4. An injection moulding machine according to claim 2
wherein disposed beneath the pivot joint is a return spring
which presses against the two members of the pivot joint.
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Description

~ 2040048
The lnvention relates to an ln~ectlon mouldlng machlne
comprlslng a machlne frame, a statlonary and a movable mould
mountlng plate and a cyllnder plate carrylng at least one
plston-cyllnder unlt of a hydraullc or electromechanlcal closlng
mechanlsm, whereln the cyllnder plate at whlch the movable mould
mountlng plate 18 supported and the statlonary mould mountlng
plate are connected wlthout struts excluslvely by way of the
machlne frame 80 that the closlng force whlch occurs durlng the
ln~ectlon operatlon and the expanslon force between the cyllnder
plate and the mould mountlng plate are only passed by way of the
machlne frame.
In DE-Al 31 32 949, whlch 18 the source of the present
appllcatlon, an ln~ectlon mouldlng machlne 18 dlsclosed whlch
has no struts. The closure forces could therefore only be
passed by way of the machlne frame. However, the afore-
mentloned publlcatlon 18 merely concerned wlth the ln~ectlon
process, and glves no closer reference to the formatlon of the
closure mechanlsm.
It has been found, however, that an ln~ectlon mouldlng machlne
wlthout struts offers better access to the ln~ectlon tool, and
this can reduce refltment tlme. However, problems arlse because
the closure forces occurrlng cannot be passed centrally, and 80
the machlne frame can become sllghtly deformed. Therefore,
rellable connectlon to the ln~ectlon tool throughout the
ln~ectlon process 18 not ensured.
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2040048 ~
The alm of the lnventlon 18 to create an ln~ectlon mouldlng
machlne wlthout struts, whereln, even when heavy closure forces
bulld up, the parallel arrangement of the mould mounting plates,
and thus a totally sealed tool, are guaranteed.
The lnvention provldes an ln~ectlon mouldlng machlne comprlslng
a machlne frame, a statlonary mould mountlng plate carrled by
sald frame, and a movable mould mountlng plate drlven by a
hydraullc or electromechanlcal closlng mechanlsm, whereln sald
movable mould mountlng plate 18 mounted to be tlltable about a
horlzontal axls to assume a posltlon parallel to the statlonary
mould mountlng plate when the closlng force ls applled.
The movable mould mountlng plate may be carrled by a plston-
cyllnder unlt that forms part of the hydraullc or
electromechanlcal closlng mechanlsm. The closlng force whlch
occurs durlng the ln~ectlon operatlon 18 passed by way of the
machlne frame, the movable mould mountlng plate belng mounted to
be tlltable about a horlzontal axls 80 that lt can malntaln a
posltlon parallel to the statlonary mould mountlng plate when
the closlng force 18 applled.
There follows a descrlptlon of two embodlments of the lnventlon,
glven by way of example only, wlth reference to the accompanylng
drawlngs, wherelns-
Flgure 1 shows an lllustratlve slde vlew of an ln~ectlon
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2040048 -
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mouldlng machlne accordlng to the lnventlon. Flgure 2 shows an
lllustratlve slde vlew of the closure devlce ln the open state.
Flgure 3 shows a slde view of the closure device in the closed
state, without the complete closure force being built up.
Figure 4 shows a side view of the in~ection moulding machine, in
the closed state, wlth complete closure force development.
The lmportant part of the ln~ectlon mouldlng machlne accordlng
to the lnventlon 18 the machlne frame 1, whlch 18 made ln one
plece wlth the mould mountlng plate 2 and the cyllnder plate 3.
Thls means that the mould mountlng plate 2 and the cyllnder
plate 3 are formed on the frame of the machlne 1. As already
mentloned, the machlne frame 1 18 ln~ected advantageou~ly from
spheroldal graphlte lron, together wlth the mould mountlng plate
2 and the cyllnder plate 3.
The mould mountlng plate 2 carrles the tool 4.
The ln~ectlon a~Leyate 5, wlth the supply funnel 6, 18 mounted
to the mould mountlng plate 2.
The ln~ectlon aggregate 5 18 not golng to be dealt wlth further
here. It 18 not an ob~ect of the lnventlon, and 18 manufactured
accordlng to the state of the art.
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B

~ 2040048 3 ~ - ~
The cylinder plate 3 carries a piston-cylinder unit 7, which, in turn, carries
the movable mould mounting plate 8 and which forms the holding
,.echanism.
By means of the piston-cylinder unit 7, the movable mould mounting plate 8
is held, by a tool plate 9, against the tool 4 of the mould mounting plate 2
during the injection moulding process.
With a closure unit where the closure force is transmitted exclusively by the
frame 1, without any struts, if the mounting plates 28 are guided with very
great force, splitting can occur in the upper region of the tool.
Therefore, according to the invention, a hinge 13 is provided in the piston in
the piston-cylinder unit 7, whereby the movable mounting plate 8 can be
placed parallel to the stationary mounting plate 4 when there is high closure
force.
By virtue of the hinge 13, the movable mounting plate 8 can be inclined, as
shown in Figure 4, so that the parallel a,ld"ge",ent of the plates is
maintained even if the stationary mould mounting plate 4 falls back towards
the bottom.
A return spring 6 is responsible for seeing that the movable mould mounting
plate 8 is guided back into the vertical position in the open state.
By virtue of the abutment 14 in the form of a pin above the hinge 13, the
inclination of the movable mould impression plate 8 and thus the parallel
arrangement of the plates can be adjusted.
By way of the device according to the invention, accuracy, with deviations
of less than 0.01 mm, is obtained in respect of the parallel arrangement of
the plates.
The important feature of the injection moulding machine according to the
invention is the fact that it has no struts.

~_` 2040048 4
It i8 important that by way of the design of the injection moulding machine
acco.ling to the invention, the space between the cylinder plate ~ and the
mould mounting .plate 2 i8 free, and th6refure the tools-4, 9 are easily
acce-~;ble.
Also, a simple removal tool 12 can be provided.

Dessin représentatif