DE1169645B - Device for molding hollow containers made of thermoplastic plastics by blowing - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: B 29 c

German class: 39 a2- 17/00

Number: 1169 645

File number: O 5402 X / 39 a2

Filing date: March 6, 1957

Opening day: May 6, 1964

The invention relates to an apparatus for molding hollow thermoplastic containers Plastics in the blow molding process with a plastic tube ejecting through a mouthpiece Extrusion press, with a linearly movable two-part neck shape, which is axially to the mouthpiece axis of a first position on the mouthpiece to be moved to a second position away from the mouthpiece can, the neck shape in the first position upon actuation of the extruder to form a container neck Filled with plastic mass and become uniform during the movement of the neck shape into the second position tube connected to the neck of much smaller dimensions than the finished container is freely pressed out, as well as with cooperating blow mold halves, which are radial to the mouthpiece axis are movable opposite to each other into a position between the neck mold and the mouthpiece, in which they enclose the pressed pipe.

It is already a process for molding hollow containers from thermoplastics Known in the blow molding process, in which first a neck and a connected with the finished neck Hose is formed, which is considerably smaller in its dimensions than the finished container is, with the hose being freely expressed from the mouthpiece of the extruder so that a As little as possible cooling of the preformed tube takes place. Before its deformation The hose is tightly closed at the lower end of the finished container. With regard to handling the plastic mass, this method is very advantageous. The ones used to perform the procedure However, machines are not so simply built and do not work so reliably that they can be used in the Mass production can be used economically.

A device for producing hollow bodies is also known, but not how In the process mentioned, a tube end is first preformed, but the mouthpiece of the extrusion press is slidingly withdrawn from the blow mold, the material emerging from the mouthpiece is pressed against the walls of the blow mold at the same time. After this known device Part has filled the mold, the bottom of the part thus formed must be closed. This However, because of the dimensions of the finished container, step can often only be carried out with difficulty.

Furthermore, a method and an apparatus are known in which, for the production of hollow bodies, apparatus for shaping hollow bodies
Containers made from thermoplastics
in the blow molding process

Applicant:

Owens-Illinois Glass Company, Toledo, Ohio

(V. St. A.)

Representative:

Dr.-Ing. H. Negendank, patent attorney,

Hamburg 36, Neuer Wall 41

Named as inventor:

George Victor Mumf ord, Orville,

Blair Sherman,

Leonard David Soubier, Toledo, Ohio (V. St. A.)

First a preform is produced in a smaller mold, which is then transferred into a blow mold and inflated to the finished body. In this method and the associated device there is the disadvantage that too much heat is dissipated when the preform is formed, so that when subsequent inflation the material no longer has sufficient plasticity.

The invention is based on the task of creating a device for the aforementioned method, which compared to known facilities of this type by their simple structure and for mass production particularly important reliable mode of action advantageously differentiates. This task is achieved according to the invention for a device of the type mentioned in that the neck mold halves Movable radially to the mouthpiece axis opposite to one another and axially to one another Mouthpiece axis movable carrier are attached, on which one connected to a piston rod, to him movably arranged control plate is supported by springs, the control plate and the neck mold halves are connected by bolts fastened in the control plate, which, in two mutually parallel Groups arranged inclined to the mouthpiece axis, in corresponding bores in the neck mold halves intervene smoothly.

The device enables the interdependent movements to be controlled and secured between a carrier, the neck mold halves and the associated blow mold. The required lifting movement can be controlled by a single cylinder, which due to the connection of the

409 588/417

individual parts with each other first the carrier vertically and then the neck mold halves horizontally and at the same time moves the core enclosed by the neck shape vertically out of the neck shape. Through the Connection between the blow molding and neck molding movement can be achieved that the neck shape closed and the associated core remains inside the neck shape until the Blowing process is complete.

Further advantages and features of the device emerge from the description in context with the drawings. It shows

F i g. 1 a side view of the device,

F i g. FIG. 2 is an end view of the FIG. 1 shown device,

F i g. 3 is a plan view of the FIG. 1 device shown,

F i g. 4 shows a partial side section through the lower part of the forming device for the workpiece,

F i g. 5 is a partial side section through the upper part of the forming device for the workpiece,

F i g. 6 shows a partial section along the line VI-VI in FIG. 4,

F i g. 7 shows a section along the line VII-VII in FIG. 4 including the upper part of the device,

F i g. 8 shows a section along the line VIII-VIII in FIG. 7,

F i g. 9 shows a section along the line IX-IX of FIG. 5,

10 and 11 sections through the neck and blow molds, the plastic material shown once before and once after expansion to the hollow shape is,

F i g. 12 shows a partial section through a modified embodiment of the device,

13 is a plan view of the removal device for the workpiece,

Figure 14 is a side view of the removal device in position opposite the neck and blow molds.

As shown in Figures 1 to 3, the device consists from a lower part 10 on which a forming device 11 for the workpiece is attached is. By means of an extruder 12 or a ram, the molding device 11 becomes plastic Material supplied in a plastic state, in which an expansion and shaping in one hollow shape is possible. The extruder 12 is driven by a motor 14 via a gear 13.

From Fig. 2 it can be seen that the plastic material is transferred from the extruder 12 to a tube forming apparatus 15, which is actuated by a piston device 16. A neck shaping device 17 can be brought down into contact with the tube forming device 15 by a piston device 18 and be separated from it again. A locking device 19 locks the neck forming device 17 on part of their commute. Blow mold halves 20 are moved inward and closed by pistons 21,22. Furthermore, a removal device 23 is provided for the workpiece.

As shown in Fig. 4, there is the pipe forming apparatus 15 from a horizontal plate 24, which is attached to vertical struts 25, and three openings having. A block 26 with three vertical cylindrical openings is fixed on the plate 24, the cylindrical openings coinciding with the openings in the plate 24. Tubular Inserts 27 are fitted into the openings of the block 26 under pressure. An orifice plate 28 with three openings is made on top of the block 26, and in the openings of this plate are inserts 28 ' fitted, which form mouths. In the middle of the tubular inserts 27 are cores axially thereto 29 provided to make tubular cavities between

ίο the inserts 27 and the cores 29 to form. the upper ends of the cores 29 cut with the surface of the orifice plate 28, while the lower Ends are screwed into corresponding core extensions 30, 31 and 32.

Each of the core extensions 30, 31 and 32 is vertically adjustable and for a slight resilience Downward movement suitably fastened. The two outer core extensions 30, 32 are with their The lower ends are pinned to short rods 33, 34 and clamped by means of threaded clips 35 and 36. The short rods 33, 34 have collars 37, 38 between the ends, over which corresponding Grip caps 39, 40, which in turn are pushed onto the corresponding fixed supports 41, 42.

The exact position of the cores 29 can be regulated by turning the caps 39, 40. Between the Springs 43, 44 are arranged on the top of the caps 39, 40 and the bottom of the threaded clips 35, 36, which hold the cores 29 in their upper position. With this arrangement, the cores 29 perform a limited downward movement against the action of springs 43,44. The middle one The core and its core extension 31 are also resiliently attached and supported by a transverse rod 45 vertically adjustable, which between two adjusting devices 46 and 47 (Fig. 6) also with Rod, spring and cap is and the same in their arrangement as those used for fastening the lower ends of core extensions 30 and 32 have been described.

As shown in FIGS. 7 and 8 can be seen, plastic material is at the bottom of the tubular Holes through openings 48 in the tubular inserts 27 and through the channels 49 in the Block 26, which is connected to a single feed channel from the extruder 12 are. The amount of plastic material supplied to each tubular cavity is controlled by valves 50 in each of the channels 49 which lead to the corresponding cavities. The valve 50 consists from a rod provided with recesses in the region of the three channels 49, so that the rotation the rod is affected at the same time the passage of the material. As further in FIG. 8 shown can the tubular inserts and cores can be of different sizes, so that tubular cavities with different Diameter are formed; the passage areas of the valve can be in different Positions are so that the amount of plastic material supplied to each cavity is variable is.

Means are provided for ejecting the plastic material from the tubular cavities; she consist of sleeves 51, 52 and 53, which in the tubular formed by the inserts 27 and cores 29 Cavities are arranged to be movable back and forth. As shown in Fig. 4, the sleeves are with a transverse plate 54 connected, which by the

Posture a movement of the neck shape; it comprises a slide 79 (F i g. 5 and 9), which through actuates a small cylinder 80 (FIG. 2) movably against the surface of the threaded bushing 77 laterally S becomes to prevent further movement of the piston. Air is passed through the cores by means of a radial line 81 in the control plate 71 (FIG. 5) and with vertical lines 82, 83 and 84 in the corresponding cores 72, 73 and 74

Piston device 16 reciprocated vertically
will. The latter has a shaft 55 with the
Piston rod of a cylinder 56 is connected. In particular, the sleeve 51 is screwed to a collar 57, which in turn is secured by a locking nut
58 is clamped to the transverse plate 54. On the same
Way, the sleeve 53 is screwed to a collar 59, which by the locking nut 60 to the
Cross plate 54 is clamped. The middle sleeve 52 is
screwed to a narrowed collar 61 which tied io.
is in turn screwed onto the shaft 55. When the slide 79 is pulled away, a return ring 61 'is permitted on the outside of the narrowed movement of the piston rod 70; a rela-Kragens61 screwed to the extreme movement tive vertical movement between the control plate of the transverse plate upwards and thus that of the sleeves 71 and the form supports 64 and 65 is possible to adjust. The upward movement of the i ₅ which forces the mold supports into an outward movement of the transverse plate and the sleeves is caused by the contact of the, the neck mold halves 62 and 63 being delimited by ring 61 'with the lower surface of the plate 24. a horizontal movement outward from the ker- The shaft 55 has an elongated transverse slot that can be opened away. This takes place against the pressure of springs 85 'between the carrier 68 and thus the shaft 55 without disturbing the position of the _{ao of} the control plate 71 (FIG. 7) through which the cross rod 45 leads (FIGS. 4 and 6).

middle core can be moved. As in Fig. 9, the slide 79 can be a

The apparatus further has a neck mold safety device to include a closing device 17 to prevent the neck molds from contacting the open ones of the blow molds from locking the neck mold ends of the tubular cavities in their uppermost position. Bringing these and producing them axially from the cavities is a function of a BoI-distant which is fastened in the slide 79. As shown in FIGS. 5 and 7, the zen85, which can contact the surface of the threaded bushing neck molding device 17, consists of a plurality of neck mold halves 77 when the slide 79 is not 62, 63, which are fastened to mold supports 64, 65. is in the locked position. The shape supports 64, 65 are in turn mounted on a horizontal 85 upwards on a second bolt 86 and lower legs of vertical plates 66 and 67 so that they can slide outwards against the pressure of a spring 87 in a zontal manner. The plates 66 for actuation; of a magnet, 88 hit. The and 67 are on a vertically movable carrier
68 attached.

The movement of the carrier 68 is through a
Cylinder 69 triggered, to which a piston rod 70 is attached
is arranged, the lower end in a control plate
71 is screwed in, which several cores 72, 73
and 74 carries that down between the neck shapes
are sufficient. Inclined bolts 75 attached to the control plate
71 are attached, lead from here in diverging ₄₀ a cylinder 93 is actuated. A pawl 94 is attached to the downward directions in the appropriately inclined Boh- end of the arm. The claw will wrestle independently in the form supports 64 and 65 and thereby form a small cylinder 95 which is attached to the pivot arm 91 by means of links 96 and the form supports 64 and 65 on the sliding connection between the control plate 71. open and closed. A movement of the claw right movement between the control plate 71 and ₄₅ arms to each other is limited to the form supports 64 and 65 by an adjusting screw, this horizontally to 97 is limited. Furthermore, stops 98 and 99 of the plates 66 and 67 reciprocate, which are provided to limit the inward or outward movement of the opening and closing of the neck forms by virtue of the pivot arm 91. After being called. Shaping the workpieces and opening the blow molding

An adjusting device is provided above the control molds, the cylinder 93 is provided for moving the plate 71 and consists of a clamping swivel arm 91 caused inwardly so that the sleeve 76, which is secured by an adjusting screw on the claw arms at opposite points of the piston rod 70 is attached, and can create a hollow workpiece in the clamping molds. Threaded bushing 77 screwed into sleeve 76. When normally closing, the small cylinder 95 is moved _{55 of} the claw 94 to close by a painterly reciprocating motion of the piston. The complete closing of the control plate 71, the neck mold halves 62, 63, where the claw 94 is prevented by contact of the links 96 with, in turn, the mold supports 64, 65 and the plate frame of the machine. The works 66, 67 and the carrier 68 is moved vertically. Pieces are thereby up to the opening of the neck shape. The upward movement of the carrier 68 is easily grasped by. Then the cylinder 93 is actuated and a stop screw 78 is limited. In the upper 60 and when the claw moves outwards, the return mold halves 20, as described in the following holding movement of the frame onto the links, are closed by the pipe lengths, and the claw can secure the workpieces and the pipe lengths will take towards that. After the workpieces have been removed to the inner walls of the corresponding blow mold cavities at a certain point, the cylinder 95 is again actuated by a pressurized fluid 65 so that the jaw opens and the work expands to form hollow containers, releasing the piece.

Fluid is passed through the cores. The working cycle runs as follows:

In addition, the locking device 19 prevents this. At the beginning, the sleeves 51, 52 and 53 are located

Magnet 88 can be connected so that it actuates the cylinder which closes the mold, prevented.

The removal device shown in FIGS. 13-14 23 is used to remove the plastic workpieces after they have been shaped. This device consists of a pivot arm 91, which is articulated at 92 on the machine frame and through

in their lowest position. The neck mold halves 62 and 63 lie over the press mouths, and the short inserts contact the top surface of cores 29 (Figures 4 and 7). The plastic material flows in the process through the channels 49 and fills the tubular cavities between the cores 29 and the tubular inserts 27. When the plastic material reaches the top of the tubular cavities approaches, the sleeves 51, 52 and 53 are moved upwards, so that more plastic material on Entry to the tubular cavities through the openings in the inserts 27 is prevented. Afterward the movement of the sleeves 51, 52, 53 is carried out further until the plastic material after is pressed into the top of the cavities of the neck mold halves 62 and 63 which form the necks. The halves of the shark 62 and 63 are then moved axially away from the openings, and the sleeves 51, 52, 53 are moved upwards at the same time, causing some of the tubular material in each tubular Cavity is caused to emerge from these and is uniformly connected to the neck.

After the desired length of tubing is removed from the tubular cavities as shown in FIG has been, the blow mold halves 20 are closed by the tube lengths, the lower end of the Pipe is pinched off without cutting it. Then a shear device 90 is operated to cut the tube from the remaining plastic material in the tubular cavity (Figures 10 and 11). Before the blow molds are closed, the slide 79 is actuated to place the neck molds in their to lock top position. The lines 81, 82, 83 and 84 are compressed air or under pressure standing fluid is supplied to the pipe lengths up to the walls forming the boundary the blow molding (Fig. 5) to expand. After the workpieces have been formed, the blow molds are made opened, and the workpieces are picked up by the inwardly directed pivoting movement of the removal device23 removed from Figs.

Before the workpieces are completely removed, the neck molds must open. This will by pulling away the slide 79 and actuating the control plate 71 upwards relative to the Form support of the neck molds carried out by means of the cylinder 69, which the neck molds by a horizontal sliding movement opens.

According to a modified embodiment of the device, the upper orifice plate 28 (Fig. 4 and 10, 11) by a plate 100 (Fig. 12) be replaced. The inserts in plate 100 are the same diameter as the cavities in that Block 26, the tubular cavities having a relatively constant inner and outer Have diameter. In this design, the entire amount of plastic material is in each tubular cavity removed when the corresponding neck shape moves axially from the cavity and its corresponding sleeve is moved upward, the necessity of cutting off the plastic material (Fig. 12) is omitted.

The terms "tubular" and "tube" have only been used to denote any hollow shape and they can apply to non-circular and irregular shapes as well.

Claims (6)

Patent claims: 1. Device for forming hollow containers made of thermoplastics in the Blowing process with an extruder ejecting a plastic tube through a mouthpiece, with a linearly movable two-part neck shape, which is axially to the mouthpiece axis of a first position on the mouthpiece moved to a second position away from the mouthpiece can be, wherein the neck shape in the first position upon actuation of the extruder to form a container neck filled with plastic mass and during the movement of the neck shape in the second position, a tube of much smaller size, which is uniformly connected to the neck Dimensions as the finished container is freely squeezed out, as well as with cooperating Blow mold halves that are radially opposite to the mouthpiece axis in a position between the neck shape and the mouthpiece are movable in which they enclose the extruded tube, characterized in that the neck mold halves (62, 63) are radial to the mouthpiece axis opposite to each other movable and axially movable to the mouthpiece axis on one Support (68) are attached to which a piston rod (70) connected to it, movable to it arranged control plate (71) is supported by springs (85 '), the control plate (71) and the neck mold halves (62, 63) connected by bolts (75) fastened in the control plate (71) are inclined to the mouthpiece axis in two mutually parallel groups arranged to slide into corresponding bores of the neck mold halves (62, 63). 2. Apparatus according to claim 1, characterized in that one in the direction of movement of the Support (68) adjustable threaded bushing (77) is provided. 3. Apparatus according to claim 2, characterized in that one in the path of the threaded bushing (77) movable slide (79) is provided, which is controlled by a control mechanism from the Locked position is movable. 4. Apparatus according to claim 3, characterized in that the slide (79) with a fluid-actuated piston is firmly connected. 5. Apparatus according to claim 3 and 4, characterized in that the slide (79) with a control device with bolts (85, 86) and spring (87) is connected. 6. Apparatus according to claim 1 to 5, characterized in that the control plate (71) for Receipt of cores (72, 72, 73, 74) is formed. Documents considered: German Patent No. 834013; French Patent No. 1114 897; U.S. Patent Nos. 2288 454, 2298716. For this purpose 2 sheets of drawings 4M 588/417 4.64 © Bundesdruckerei Berlin