DE6751924U - TWO-CYLINDER MOLDING PRESSES - Google Patents

Description

~ u: m ~ nh-u.

DR. EULE DR. BERG DIPL.-ING. STAPF

PATENTANWÄLTE B MÜNCHEN 2. HI LB LESTR ASS E ZO

• Df. CuIa Df. DefQ Dlpl.-Inp. Slopf, Q Monchen 1, HilbloslroBe 20

(Kr J! "W>" n Unier symbol

.id. «. ^Y1 / ^Kx Da ^ _n , July 26, 1968

Lawyer files no . Ϊ7 521

Star of david. Y / indsor, Berkshire / England

Two-cylinder compression molding

The invention relates to a plasticizing device and to a method for plasticizing plastic material .

(08Tl) * 5 16 20 81 Telegrams: ΡΑΪΕΜΤΗΛΕ MSncfien Bant: Bcyarisci »V-remsbant Mündien <53 ICO Posisd-.ecfc: Munich 653 · 43

The invention provides a device for generating a flow of plasticized plastic material with at least two chambers connected in parallel to a common outlet opening, devices WxM plasticizing the material in the chamber assigned to each chamber and a device for pressing the plasticized material from each of the chambers into the outlet opening, means being provided for blocking each of the respective chambers from the outlet opening.

In one form of the invention, the locking device is such that only one chamber at a time the outlet opening can be in communication.

In another form of the invention the locking device is such that both chambers are in communication at the same time can stand with the outlet opening.

The invention comprises an apparatus as described above in combination with an injection molding machine in which the The outlet opening of the device for felling one or more injection molds is arranged in the injection molding machine is.

The invention further comprises an apparatus as described above in combination with a blow molding machine, in

- 3 -

which arranged the outlet opening of the device for filling one or more molding tools in the blow molding machine is.

The invention further comprises pre-cleaning as above described in combination with an extrusion die that can be operated as an extruder.

The invention also includes a method of generating a stream of plasticized plastic material in which the material is plasticized in at least two separate chambers, the chambers are connected to a common outlet opening and the plasticized material is pressed from one of the chambers to the outlet opening, while another or the second chamber with Material is refilled and the material is plasticized in the chamber.

Preferably the plastic material is pressed into a mold after it has left the exit opening and the mold is completely filled with material from only one chamber.

In this form, a second mold can be completely filled from a second chamber while the aforementioned a chamber is filled with new material and this

is plasticized *

In another form of the invention the plastic material pressed into a mold after it has left the outlet opening, and the contents (or a part of the contents) is used by more than one chamber to fill the mold.

-JJIn the latter form a first chamber is preferably connected to a '^ eil to fill-you of the mold is then separated from the mold and a second chamber is connected to another' to fill l ^l eil of the mold.

Optionally, a first chamber is connected to a 'Fill part of the mold and it will add a second chamber' -,

üie form attached, -the to another part of the form § & ^ - "lf ^ ^ iwli '*' ^to fill ^ before the first chamber of the form: setrennt

Asa «.«. tfCte. * - * AA'Fi-e-iL. ¹ "j .. ■ _ - ^D

will.

The first chamber can be used more than once to fill the mold.

In another embodiment, the chambers can be sequential be connected to the outlet opening, i.e. without interrupting the flow of material.

- 5 -

(O - 5 -

ils will now some preferred embodiments of the invention by way of example with reference to the drawings.

Fig. 1 is a schematic side view of a typical one Injection molding machine.

Figure 2 is a plan view of an injection molding machine

Fig. 3 is a perspective view showing a feature of the invention can be seen in which a rope has broken away.

Fig. 4 is a schematic view of a valve used in a first embodiment of the invention is, in three operating positions.

Fig. 5 is a schematic view of a valve used in a second embodiment of the invention will, also in three company presentations.

Fig. 6 is a schematic view of a rotary valve for intermittent or continuous operation,

FIG. 7 is an illustration of the valve according to FIG. 6 arranged for actuating a luikrooch container.

Figure 8 is a schematic view of a set of slider valves for intermittent or continuous operation; and

Pig. 9 is an illustration of a valve of FIG. 8 in FIG Arrangement for operating a microswitch.

i'igs. 1, 2, 3 and 4 represent a first embodiment of the Invention when applied to an injection molding machine. nine dar.

Like in Pig. I "owns a typical injection molding machine a closing head 11, a movable mold plate 12, a fixed mold plate 13 and an injection mold 14, which is formed from two files, one part each attached to one of the mold plates so that the molded parts be closed when the "" ormpiatte 12 against the Mold plate 13 is moved * The machine has an injection unit 15 and rotary and thrust motors 16, which Drive injection unit 15.

According to the invention, an injection unit as in ^ ig. 3 is shown a discharge opening or nozzle 17, the of two plasticizing devices arranged in parallel A and B is fed. The plasticizing devices have Heating strips 19 which enclose stationary housings 20. Inside each housing 20 is a son corner piston 21

arranged, which rotates within the housing and also moved axially with respect to the housing when it is driven by the motors 16 »

Both plasticizing devices are cut from a filling funnel 22, which is arranged above the plasticizing devices at their end remote from the nozzle ο Each plasticizing device feeds the material to the nozzle via a rotary valve 18 which is actuated by a rotating actuating device 23. The rotary valve is in Pig. 4 schematize. shown. The valve has a cylindrical housing 31 which has three passages arranged in a plane perpendicular to the axis of the housing, two passages 32 and 33 being offset by 90 ° with respect to the third passage 34. The passages 32 and 33 lead to chambers at the ends of the plasticizing devices A and B facing the nozzle, and the third passage 34 leads directly to the nozzle. Within the housing is a rotatable feeding member _r 35, which has a knee channel 36th The knee channel 36 extends between two points on the surface of the feed element 35 j which are offset by 90 ° in a plane perpendicular to the housing axis: brought an intermediate position in which

none of the outer passages 32 and 33 mil; your channel 36 is connected. The three positions of the locking element are at I, II and III in I ¹ Xg. 4 shown.

In operation, the Schneckenkclbeneleiaent 21 is in the Plasticizer B initially in a "forward" position and is set in rotation. The Liateria.1 fails the hopper 22 on aen h.inx ~ r & r · 2eil der- screw. The screw and the cylinder walls are dimensioned so that the material from the upper end along the screw into the located immediately in front of the front end of the screw. Chamber is transported. The snail is through the increasing amount of material fed into the chamber in front of the screw is pushed backwards. The speed, with which this transport takes place from the back to the front is determined by the power and length of the heating tapes, the design of the worm, the power and speed available for the rotation of the worm and through the nature of the raw material determines which during its transport from the outer to the front The screw end is converted from a shape that is customary for the raw material into a state suitable for injection molding will ·

When the auger has reached a rearward position, it is driven forward and presses the material through

the passage 33, the knee channel 36 and the nozzle 17 in the
closed molded parts 14, with all the free space in

the mold is filled with the plasticized material. j

The snail exerts even more forward pressure on daa f

Material from until the su formende ^ sil in sinsm Stegv'sil ϊ

the shape has solidified. The rotary valve 18 is in the position |

lung II switched and thus blocks the form from the He- |

removal of the injection molding. j

The screw piston 21 begins its movement as above \

described anew. ι

Y / while the plasticizing device B from the filling I

hopper is loaded, the plasticizing device is A |

via the rotary valve 18, the passage 32 and the knee channel I.

36 connected to the nozzle 17. The two plasticizing units- jj

directions rotate and move alternately from the |

Büse Y / eg to plasticize the material from the hopper

fify, and move forward to the material in ⁱ

to press the mold. ¥ ¥ while the plastic material consists of a
Plasticizing device is injected into the mold,
hard 'and removed from the mold, the other becomes
Plasticizer operated to remove the raw material
the filling funnel into a shape suitable for injection

- 10 -

κ ^κ · U / α

to convert.

Depending on the choice of material, the thickness and shape of the The injection molding and the weight of the molding in relation to the performance of the machine, the molding can be made from dsr Forin sntfsrnt rverdsn before dis snail gejiugeHd material for the production of another compact from your hopper i-iastified and transported into the anterior chamber Has. Under these circumstances, the molding of another compact must be delayed until a sufficient one Amount of raw material has been processed by another screw 21.

The output of the machine is then determined by the speed given with which a given plasticizing unit can process the material during the time in which the son's corner is not busy with its other functions

is requested *

A typical sequence of two consecutive work cycles using the device is now described as an example:

A 196 g heavy polypropylene compact is produced on units that have a plasticizing capacity for this

- 11 -

Have material of 14 g per second and on which the injection phase lasts 3 seconds, the consequence of which is the removal of the compact from the machine is as follows

Injection (A) 3 seconds) Plasticizing during

-, λ α_, * _ " \ unit B

XU u0jB.u11u.eii;

Emptying 3 seconds

Injection (B) 3 seconds

14 seconds

Plasticizing for 14 seconds Unit A

Hold for 10 seconds

Emptying 3 seconds)

32 seconds for 2 pellets.

It should be noted that the embodiment described above Both on a blow molding machine and on an injection molding machine can be used.

, In a two _u en embodiment of the invention as described in Pigs. 3 and 5, the plasticizing devices are connected to an outlet or a mouthpiece which is designed as an extrusion mold. In this embodiment, shift valves 18A are used. As shown schematically in Figure 5, channels 40 and 41 lead from plasticizers A and B, respectively, and channels 42 and 43 to the extrusion die. The "valves have sliding parts 44 and 45 which can be arranged so that they

- 12 -

I '

either connect channels 40 and 42 or 41 and 43

or shut off.

j In this embodiment, the screws 21 press off

it alternately plasticizes material through the extrusion nozzle in a continuous extrusion process.

Continuous exit from the mouthpiece is achieved through the use of shift valves ISa in conjunction with the screw 21, which operate as follows:

At the beginning the screws 21 in the plasticizing devices A and B are in the front position. The snail in the Plasticizing device A is rotated and thus transports material to the space in front of the screw, whereby the Screw is moved back at a corresponding speed.

'- ■' '■' ■ £

When the valves are in position I, ie A corner Sehn forward 'is pressed and passes the extrusion a through the mouthpiece. During this time the screw 21 in unit B is set in rotation and transports the material into the Raxan in front of the screw, the sun screw moving back at a corresponding speed. The screw B reaches its rearmost position before or at the same time as the moment in which the screw A reaches a position

- 13 -

shortly before its foremost position, the valve reached 18a are brought into position II and at the same time the screw B begins its forward movement. At this moment both units A and B cause the material to exit through the mouthpiece.

The worm A begins to rotate and at the same time the valve 18a is brought into position III. The screw A transports the material into the space in front of the screw and moves back at a corresponding speed while screw B continues extrusion. The snail A reaches its rearmost position before or at the same time as the moment in which the snail B reaches a position reached shortly before their foremost position. The valves 18a are brought into position II and begins at the same time the screw A its forward movement. At this moment both units A and B cause the material to escape from the mouthpiece.

The applied to the augers 21 during their forward stroke Force can be controlled so that the pressure and speed applied to the raw material, with which the material is pressed through the MundatUok, constant during the vior phases described above remain"

- 14 -

In this continuous extrusion arrangement, the rotating motion of the screw is primarily used for plastic fication, while the separate piston-like movement provides that required to force the material through the mouthpiece Pressure guaranteed.

The screw piston 21 can by the action of a hydraulic pump be driven forward, the hydraulic fluid with a constant flow rate ent.eder one the piston feeds or both at the same time. Yfenn both Pistons are actuated at the same time, the single speed is the forward movement half the speed that is achieved with only one piston forward is moved. Thus a constant flow rate is maintained through the extrusion die.

Another embodiment. A rotary valve is in Pig. 6 shown. In this case, the passages from the plasticizers A and B are at 90 ° to each other and around 120 advances against the passage leading to the mouthpiece. In position I, the plasticizing device B supplies the Mouthpiece, in position II the mouthpiece is blocked and in position III the plasticizing device A supplies it the mouthpiece.

It should be noted that if the! Eeil 25A was IBQ ⁰ in

- 15 -

751924

is rotated to its position II, both passages 50 and 51 are in connection with the passages 23a and 33a, so that the mouthpiece from both plasticizing devices is supplied at the same time. As a result, the rotary valve according to FIG. 6 can be used in an extrusion arrangement,

Fig. 7 shows the valve after 5 ¹ Ig. 6 (in position I) when a microswitch 52 is actuated between position I and position III to initiate a further partial process of the machine cycle.

Fig. 8 shows schematically the operation of a set of linear valves which can be used for injection molding (or blow molding) as well as for extrusion. In Fig. 8 two linear valves are shown and movable parts 54 and 55 are slidably disposed in guides 56 and 57, respectively, and each movable part has a passage 58 and 59.

In position I, passage 58 allows injection into a compression molding machine from unit A while unit B is locked. Both units are in position II Blocked and in position III, passage 57 allows cLas to be injected into the compression molding machine from unit B.

In another arrangement (position IV) the material can be made from both units at the same time in the FormpreSmagohine

16

are injected «,

I ¹ Ig ₀ 9 j which is an axial section through one of the L? - represents axial valves according to I ¹ Ig ₀ 8, shows the actuation of a microswitch 60 by the valve to initiate a further "-eil" process of the main cycle.

When the apparatus is used for intermittently supplying ^ on plastic material (DOH., Injection or blow molding), either a rotary valve for two associated injection units, such as in 3 ¹ Ig * 4 can be used, or there may be a slide valve for each Mnspritzeinheit used , as in -U'ig. 5 * In the latter case, both channels would be blocked in position II in FIG.

- 17 claims

6?

Claims (1)

Zyi - claims: 1. Device for generating a stream plasticized PlastiJfcmaterials with at least two ^ amners, each of the Chambers associated facilities for plasticizing the Material in the chamber and a j ^ iu? Gage for pressing of the plsitized material from each of the chambers an outlet opening, characterized in that the Chambers connected in parallel to a common outlet and that means are provided for shutting off each of the chambers from the outlet, 2. Apparatus according to claim 1, characterized in that the shut-off device is such that only one chamber can be in communication with the outlet at any one time. 5. Apparatus according to claim 1, characterized in that the shut-off device is such that both Karrjner at any time may be associated with the exit. 4. Device according to one of the preceding claims in combination with an injection molding machine, dadurc \ characterized in that the outlet of the device to the puller, one or more molds is arranged in the injection molding machine. - 18 - Vcrric..tv.r.P "ge:., Rl. '; A natici. nit ei.--.er -Ιε-cf for the Av.s kicking the gate: ic. t so: .oi- Iv:. \; rc :. ■ f ' "■ ■ C- C · 6. Vorrichxung enjoyed one, aer claims 1 Dis 5 ₅ lc combination with a Strs-npreßform, aadv.rch gekemizeicnnet that the device to operate al. Extruder is arranged. -7 - »- i ^ of a St-i'os Plastic material that allows the pias ification of katerials at least in two separate rabbits, characterized in that that the chambers are connected to a common outlet and that this piasxified Material from one of the chambers to dei .. Carrion comes out pressed v / ird, while another or the second chamber with material refilled and the material in the K.a;:.; .. he plasticized v / ird. 8. The method gerp-ä ^ claim 7, characterized in that the plastic material is pressed into a press mold after it has left the / exit, and that the mold with lua ^ feerial hur from a .uai.mer ". ollcome filled v / ird. TTi'c "^ 8-5 ^ -ej ο: οο-a-e-t-y-d-aß - 19 - pa *