DE6605115U - DEVICE FOR CLOSING AND OPENING THE MOLD OF PLASTIC PROCESSING MACHINERY, PRIORLY INJECTION MOLDING MACHINES. - Google Patents

Description

PATENTANWALT DIPL.-INQ · W SOfoMf ^. 'Feä-WUPPERTAL-BARMEN' »'

66.5580 A m / m
K 54 027739a ffbm

Device for closing and opening the 3? Orm of plastic processing machines, primarily Injection molding machines.

It is "known that with duckmittelbetätigte Closing devices the closing force from the cross-sectional area and the specific pressure of the pressure medium is directly dependent. This "entails" on the one hand the cross-sectional area when high forces are desired a pressure medium, e.g. a hydraulic cylinder and on the other hand, the specific pressure of the printing medium must be large.

There is a longitudinal movement of the piston in the hydraulic cylinder to generate a clamping or closing force

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is inevitably necessary, it is clear that the "required amount of the print medium with the largest longitudinal movements and the energy required to generate a correspondingly high pressure medium is an essential factor represent such a facility.

An example of such closing devices is a hydraulic closing unit of a plastic injection molding machine, in which two molded parts have to be pressed against one another with great force in order to ensure that the injection process runs smoothly. Depending on the size of the machine, the clamping forces to be applied are in a range of 10 to 1000 to and more. Venn is doing once in loading ^ _n costume draws that hydraulic pumps currently print media

a pressure of up to about 350 atü only with the greatest energy consumption, This requires correspondingly large effective piston areas in the units. Since also the longitudinal movement of a molded part depending on. Machine size can be about 100 to 1000 mm and more is too

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recognize that the demand for print medium is very great if you add the number of movements in the unit of time considered.

Based on the knowledge that for the shifting movement of one side of the mold - empty pre-stroke - to to be placed on the opposite side despite the larger Yorschubweges lower thrust forces are necessary than for the actual closing process, is one in practice Device for closing and opening the mold of plastics processing machines, primarily injection molding machines became known, with a fixed and a movable form carrier ^ plate, as well as one Pressure medium unit for performing the mold feed movement on the one hand and a mold closing movement on the other became known, in which two pistons are used, of which the piston has a smaller cross-sectional area than the gate piston and the piston with larger Cross-sectional area serves as a closing piston. Each piston is driven by a separate one

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Drive unit acted upon.

After the piston with the smaller piston area has ended its feed stroke, the device is mechanically locked. Only then is the other piston acted upon.

Compared to such a device, what is new and inventive is the present innovation in that the form fit of both molded parts in the

Fully closed position of the mold by the pressure medium only

a single pressure medium unit itself via a

s that loads directly axially on a stepped piston

S pressure cushion is effected, which can be controlled by a preferably pressure-controlled valve, preferably by a check valve.

The present innovation, in which the cylinder generating the clamping force is positioned over the pressure medium of the feed cylinder - pressure pad - supported, and where

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by, a valve both pressure chambers closed against each other offers a number of practical applications, not just in injection molding machines Exercise and application options, but can also deviating from this for ac-lere Closing movements are used with advantage.

The practical realization of the subject of renewal is also extremely advantageous for the reason that it has been possible to do this for the first time on a locking device of the type mentioned at the beginning, pressure medium, e.g. hydraulic oil, is necessary anyway not only to be used to carry out the feed and the closing movement, but also to use it to assign further functions by using it as a pressure pad for locking the fully closed position of the mold used as well as to control the valve. In this way, the innovation stands out compared to previously known ones Devices and also makes previously known mechanical locking devices after termination the feed stroke dispensable.

If now - following the proposal of the innovation, the valve is to be actuated by the pressure medium, it is expedient if this is carried out at one end as a piston rod and at the other end as a cylinder-like receiving space guided by its own pressure medium supply actuatable piston trained release needle is controllable.

Here, a practical realization of the innovation can find its expression in the fact that the Stepped piston is designed as a hollow piston provided with a central axial passage, in which the release needle mounted on the lock cylinder side is cantilevered, which the feed piston side in The stepped piston controls the check valve provided.

This embodiment offers particular advantages in this respect, as well as for the implementation of the pre-club as well also the closing movement requires only a single pressure medium supply, preferably on the locking cylinder side is.

A further training in this direction could also be implemented in such a way that the feed piston side Bottom part of the feed cylinder as with an axial opening for receiving the check valve and for guiding the lifting needle trained hollow bottom is executed.

In this embodiment it is then called

d considered particularly advantageous that a massive,

i.e. axially uninterrupted piston on the one hand and

on the other hand, a much shorter lifting needle is obtained, if '", one also has an additional central connection to the

Actuation of the feed piston required.

; · In summary, both embodiments remain

in common that the pressure medium is used to over the small feed piston the fully closed position of the

j shape to lock without becoming previously inevitable

having to use expensive mechanical aids, whereby structural and functional advantages are achieved.

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If finally still proposed according to the innovation is to combine the fixed mold carrier plate with the clamping unit to form a fixed structural unit, so this should also only be viewed as a suggestion, whereby it is of course also meg = lent would be to arrange other parts of the device spatially fixed and the corresponding opposing parts movable.

In the drawing, 1 is a with the execution

In addition, the innovation is based on the example of an injection molding machine reproduced on I of the accompanying drawings shown, with only those parts are shown that are necessary for understanding the function of the innovation item; namely show:

Fig. 1 is a plan view of such an injection molding machine in longitudinal section, and

Fig. 2 shows the same representation of a modified embodiment. ι _{£ | r}

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example preferably called a fixed plate with hubs and a hydraulic cylinder jacket. In the hubs, the bars 2 are axially displaceable * Λα the left ends of which is a mold carrier plate 3 by means of clamping rings 4 or the like. firmly connected to the Homen 2. The mold half 5 is fastened on the Pormträgerplatte 3, while the second mold half 6 is held on the mold carrier plate 7. Bearing receptacles in the mold carrier plate 7 allow the spars 2 to move axially therein.

In the plate 1, a control piston 8 and an actuating rod 9 having a lifting needle is housed. The cover 10 serves to cover the resulting housing opening. Furthermore, a piston ΛΛ - closing piston - is accommodated in an axially displaceable manner in the cylinder jacket of the plate Λ. The cover 12 serves to limit the oil space. The piston 11 is axially - on the drawing _v to the right - as a piston rod and further again as a piston 14 - advancing piston - and represents a stepped piston which is hollow over its entire length is.

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In the embodiment according to the Jig. 1 is the Stepped piston 11, 15 as a hollow piston to accommodate the lifting needle 9 and carries a valve 13, advantageously a check valve, at the right end. From one accordingly the piston and piston rod diameter Cylinder jacket 14, which is at its left end is closed with a cover 17 and connected to a transverse plate 16 as well as this is connected to the spars a connection is made e.g. via clamping rings 4, is the Feed piston 15 added.

The pressure medium connections e.g. to a Hy

The hydraulic power unit is marked with the letters A, B, G and D. designated. A liquid, e.g. hydraulic oil, is used as the pressure medium.

The new locking device according to 3Pig. 1 is in the open position, i.e. the two Eorm halves 5 and 6 are so far apart from each other that the conditions are met that are necessary for a

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free demolding in plastic injection molding machines are desired.

In this position, the hydraulic connections G and D and the associated oil areas in the cy- ' relieve pressurized oil. To close the mold halves, i.e. to move the mold hinge 5 in Alignment to the mold half 6 - i.e. to the right in the drawing - pressure medium, e.g. pressure oil, is passed through the Connection B brought into the cylinder system. Connections A and G can be under pressure, the pressure medium now flows through the hollow piston rod of the stepped piston 11, 15 via the check valve 13, and moves the cylinder jacket 14 and the insulation plate 16 and the bars 2 together with the standard carrier plate 3 with cLer

Porm half 5 to the right in Eichtung on the Porm half

6. The oil in the feed cylinder - to the left of the piston can be fed through port D however, there is drainage of the oil through port C. not possible.

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This movement - feed movement - lasts until the two mold halves touch. At this point in time, the hydraulic control is influenced mechanically, electromechanically, electrically or in some other way in such a way that the oil still present to the right of the piston 11 can now flow out through the connection C, that is to say that this area is depressurized. As a result, the piston 11 moves to the right - closing stroke - under the influence of the pressurized oil still flowing in through port B. The resulting force is transferred to the cylinder jacket 14 via the oil column - pressure cushion - which is located to the right of the piston 15, and the flow of which is prevented by the check valve 13 - and via the transverse plate 16 to the spars "which now form the mold halves via the mold carrier plate 3 5 ″ and 6 press against one another with the force resulting from the cross section of the piston 11 and the hydraulic pressure of the oil, whereby the locking of the fully closed position of the mold is achieved.

At a pre-selectable time after

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the closing process, which can be selected e.g. via timers, is the influx of pressure oil to the connection B "ended. It is then via the connection A to the control valve 8 and via the connection G to the piston 11 pressure oil supplied with the result that the lifting needle 8.9 moves (to the right and the piston 11 to the left, with

the check valve 13 is opened. The one on the left Oil from the piston 11 can flow off via the connector B. Pressure oil is now supplied through port D, causing the advance cylinder 14 to move to the left can with simultaneous displacement of the oil located to the right of the piston 15, which is now through the Check valve held open by the operating rod through the hollow piston rod of the rod piston 11.15 can flow off via connection B.

After the opening process has been completed, through appropriate control elements - mechanical, electrical or otherwise - a new closing movement takes place or the open state can be maintained.

The embodiment shown in FIG differs from that according to FIG. 1 in that that the stepped piston 11, 15 as axially uninterrupted Piston is formed. The required check valve 13 is located in the bottom of the Feed cylinder 14-. Also the air needle that came out

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Control piston 8 and piston rod 9 consists, is received here in the bottom, the bottom opening through a Lid 10 is closed.

The loading of the Yorschubkolbens 15 takes place here not by a pressure medium filling within

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of the stepped piston 11, 15 ·> but rather via the connection B provided in the cylinder jacket.

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Impact of the piston 8 is controlled here via the connection A in the cover 10. Otherwise the function is same or similar to the control as in the embodiment according to Fig. 1.

Last but not least, it goes without saying that the illustrated and described embodiments

are only examples for the realization of the innovation, which, however, are by no means limited to this alone rather, various other designs and applications are possible within the scope of the innovation.

Claims (6)

Protection claims: 1. Device for closing and opening the mold of plastic processing machines, primarily injection molding machines, with a fixed and a movable mold carrier plate, as well as a pressure medium unit for performing the mold feed movement on the one hand and a mold closing movement on the other hand, using two pistons, of which the piston is smaller The cross-sectional area serves as the thrust piston and the piston with a larger cross-sectional area serves as the closing piston, characterized in that the positive _{locking of both mold parts (5 5} 6) in the closed position of the mold by the pressure medium of only a single pressure medium unit itself via a directly axially on a stepped piston (11, 15 "or 11, 15) on the pressure cushion is effected, which is preferably controlled by a pressure medium-controlled valve (15 J · CS "or 13)" is preferably controllable by a check valve is. 2. Apparatus according to claim 1, characterized in that the check valve (13 "or 13) by ') one end as a piston rod (9 or« η ) and at the other end as guided in a cylinder-like receiving space, by its own pressure fluid supply (A or A) actuatable piston (8 or 8) designed release needle is controllable. 3- device according to claim 1, characterized in that that the stepped piston (11, 15) than with a central axial passage provided hollow piston is formed, in which the locking cylinder side mounted Lifting needle (8, 9) is received in a cantilevered manner, which is provided on the feed piston side in the stepped piston Check valve (I3) controls. 4. Apparatus according to claim 1, characterized - II - ■ I I I I « draws that the feed piston-side bottom part of the feed cylinder (14) is designed as a hollow bottom with an AxM breakthrough for receiving the check valve (13) and for guiding the Iiüftnadel (β ' ¹ .9 ^). 5. Apparatus according to claim 1, characterized in that that the fixed mold carrier plate (1) with the closing unit to form a fixed structural unit is united. 6. Device according to A ± n © n · .dar the preceding claims, characterized in that the lateral support bars (2) are fixed and the mold support plate (7) with the mold half (6), which is a structural unit with the closing unit, are movably arranged. * - Ill - 11th