DE2063850A1 - Injection molding process for the production of two-tone injection molds in an injection molding machine which has two molding devices made of metal - Google Patents

Description

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December 21, 1970 IG / st

Katashi Aoki

6037, Oaza Minamijo, Sakaki-machi, HanisMna-gun, Nagano-ken, Japan

Injection molding process for the production of two-tone injection-molded parts in an injection molding machine, the two molding devices made of metal having.

Here, the first should be produced in the first molding device Injection molding, after it has solidified, can be transferred to a second molding device using a stripping device Component, after which the molded part is introduced into the second mold itself, where this molded part is replaced by a second Molding compound is encapsulated or injected, and this second molding compound has a different color »

It is already known a method in which existing in the first% metal molding device moved by the injection molded part produced in a preceding Formh'älfte or outer shape of the first forming means to second forming means and is inserted into the hollow half (lower mold) of the second shaping means , and there is subjected to a second injection process using a molding compound of a different color. However, this method is in need of improvement, as the first and second mold devices must have a design in which the lower molds of the first and second mold devices must be operated together with an upper mold. However, the disadvantage here is the free selection of different form upper-

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halves for the first and the second molding device completely dispensed with. A further disadvantage is that the independent Design of the molded part that should have a different color with respect to the first molded part, is severely restricted.

The invention is based on an improved injection molding process and an associated device which allows in to use different mold halves, e.g. upper molds, of the first and second mold devices. Furthermore, according to the invention the range of free choice of that part of the molded part, which is one with regard to the part molded first should have different color, be enlarged significantly.

Furthermore, the known method and the injection molding machine be improved in such a way that only a minor rotation of a mold half, in particular the upper mold, is necessary, and that the structure of the machine is significantly simplified. Furthermore, the invention should be achieved that in an improved Two-color injection process it is no longer necessary to bring the upper mold with the two lower molds to cover, whereby the shape of the molding devices is also significantly simplified.

According to the invention it is proposed that a first colored molding compound be injected into the first molding device _: and waiting for solidification until the first molding has been formed, then the first molding is removed from the first molding device and stored on the stripper plate or supported there, then this stripper plate is rotated and the injection molded part that remains on this plate is moved or driven into the second molding device or between the upper and lower mold, furthermore the second molding device is closed and a second molding compound of a different color is fed into the second molding device * -

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is splashed. According to the invention, a plate-shaped, reciprocating and rotatable one is used here Wiper between the upper and lower mold of the molding devices, this wiper plate supporting or during the movement of this plate. The stripper plate can be moved freely to and fro, in particular axially Direction of the machine, as well as rotatable or rotatable. According to another embodiment of the invention, that of the first Injection molding removed from the molding device is transported from or on the stripper plate to the second molding device.

These and other embodiments of the invention are shown in the drawing and are explained in more detail below. Show it:

Fig. 1 is a longitudinal cross-section of a two-color injection molding machine for carrying out the invention Procedure,

Fig. 2 is a longitudinal section of the same device

in a working position, with the molded part about to be ejected,

3 shows a longitudinal cross-section of the same device in a working position, the stripper plate is offset by half a turn from the position shown in Fig.,

Fig. 4 is a longitudinal section of the same device, the hosing in the working position of Fig. 3 takes place,

5 shows a longitudinal section of another embodiment of the device, with an injection molding

just taken from the metal form Wi (Ti and

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Fig. 6 is a longitudinal section of another embodiment ^ - shape of the machine, whereby the stripper plate is actuated by half a turn

In the two-color injection molding machine according to FIGS. 1-4, upper halves or upper molds 1, 1 ^{1 are} attached to a support plate 4 which is made in one piece with a piston 3 which is mounted within a hydraulic cylinder 2 »Compared to the upper molds 1, 1 ¹ there are lower molds 6 _S 6% which are connected to the respective injection nozzles 5, 5 ', weleli © are arranged on a rigid plate 7. From the drawing it can be seen that the upper molds 1, 1 ¹ differently permitted molded parts 1a, 1a ' exhibit.

Between the support arms 8, 8% which protrude from the hydraulic cylinder 2 and the plate 7, guide rods 9, 9 ″ extend, and the support plate 4 is loosely attached to these guide rods so that the upper molds 1 ″ 1 ^e mounted on the support plate 4 along the Guides 9, 9 * can be offset or displaced in the direction of the lower ^{molds 6, 6 9 until the support plate 4}

an abuts against stops 10, 10 * ",, which the guides 9j> 9 * are attached.

Between Obsrformen 1, 1 'and the sub-forms. 6, 6 * ″ there is a stripper plate 12 which is connected to the end of a shaft 11 which penetrates the piston 3 and the support plate 4. Through openings 13, 13 'extend through the stripper plate 12 and serve to support the upper molds while these through openings 13-13 * are concentrically surrounded by holding seats 14, 14 ', which serve to hold the injection molded parts. By protruding parts 15-15 "of the upper molds 1, 1 ^f , the stripper plate 12 is made into eli'y sugefeiirene Sp Ritz position where the Site® 14p 14 ¹ comes into contact with the interforms 6 _V 6 * _. wherein in the it MPiien molding compounds i

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Lent color can be injected.

At the other end of the axle 11 provided for the stripper plate 12, a toothed wheel 16 is provided which is thickened in the longitudinal direction and which engages with a toothed rack 17 on the piston rod 20. This rod is connected to a piston 19 which is mounted in a hydraulic cylinder 18. Stripper plate 12 is rotierb by half a turn, driven by gear 16 and rack 17, when piston 19 in hydraulic cylinder 18 is adjusted vertically. Is also the axis is provided with a flange 21, 11 which λ is an enlarged borings tion 24 was added, which is formed as a part of a guide bore 23 for the shaft, in which a bore is made through the supporting piston disk. 4 An intermediate coupling part 22 connects the piston and the support plate in such a way that the axis 11 can be moved back and forth over a predetermined axial length of the enlarged bore 24.

The injection molding machine operates as follows: in the working position according to Fig 1 engage upper molds 1, 1 ¹ with the respective molds 6, 6 · together, and a molten resin is injection nozzles 5, 5 ¹ in the respective cavities in |. Injected molding devices. At the same time, an injection molding of different resin color is in the top mold! ' and lower mold 6 'are formed as follows.

Bin first SpritzLLng formed zwLBChen upper mold 1 and l / nturform 6, of the first color, together with the upper mold I and of the stripper plate] 2 of the lower mold t> such as from i ^'l ig. ' can be seen, pulled away, whereby the absbrtit'erplabto \ 2 is angohul.ton by stops 10, K) ¹ on the guide rods, so that only the overform I is withdrawn further, but the molded parts M, M remain on the stripper plate 12.

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In this way, molded parts M, M * are completely removed from the Porm facilities removed. Since the sprue M "as out As can be seen below, the two-color spraying process has ended, it is ejected from the stripper plate 12 or repelled, while the first molding M, which only has the uniformly molded shape, on the holding seat of the stripper plate remains.

In this working position, the hydraulic piston 19 is actuated, the axis 11 of the stripper plate rotates by half a revolution through the rack 17 and gear 16, which means that the molded part, which has ended the first part of the injection molding process, into the further working position is transported to the second molding device. In other words, the Erstspritzling M is now in a working position between the upper mold 1 ¹ and the lower mold 6 ', see Fig. 3, placed, after which the supporting plate is moved in the direction of sub-molds 4.

From this it follows in turn that the first injection molding M is ^{inserted or retracted into the lower mold 6 1 of} the second molding device with the help of the upper mold 1 'and is arranged on the support plate 4 until the second molding device is firmly closed. Then a different-colored "artificial resin" is injected via injection nozzle 5 ¹ into the cavity formed by the upper mold 1 ', this cavity having a different shape 1a ¹ compared to the shape la on the upper mold 1 of the first molding device in connection with the lower mold 6 'of the second molding device was formed, which cavity was used to form the first prototype M. Now, after the second injection, the iJprLbzLing M ¹ , which has two-colored parts, is obtained. During the working hours, the first injection molding M is injected simultaneously between the upper mold 1 and the lower mold 6 of the first molding device, see FIG. 4. Then wiper

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Plate and support plate 4 withdrawn, and the two-colored molding M ¹ falls out. By repeating the above procedure, two-color molded articles are continuously obtained using only one injection machine.

In the second embodiment of the machine according to FIGS. 5 and 6, a shorter guide bore 23 * is used for the axis which does not reach the piston 3 _; and through the seat plate 4 and the central coupling part 22 is drilled. Furthermore, a shortened axle 11 is used, which is attached to the stripper plate 12 through the bore 23 *. A part 25 g of the axle 11 has a square cross-section, and in this part of the axle a gearwheel 16 'is slidably mounted. At a square end 25 of the axle 11, a flange 25 * is provided as a stop for the gear 16 ^f so that it does not; can slide off the axis 11. Furthermore, another bore or the like extends. 26 laterally through the connecting coupling part between the support plate 4 and the piston 3 'and through this bore 26 a rack 17' is inserted. Even if the design according to FIGS. 5 and 6 does not show all the individual parts, it is understandable that the rack 17 'is acted upon by a hydraulic piston and associated cylinder, as explained with reference to FIGS. 1-4, and the axis 11 un 180 ° is rotated when the ^ j rack moves laterally through the hydraulic device. It is to be noted that a hydraulic device ld is not operated, when the stripper plate vorwäite 12th or backwards. Other parts of this embodiment of the machine correspond to those shown in FIGS. 1-4. The differently designed component such as 1a ^f can be provided on the inner surface of the lower ^{mold 6 1} as well as on the upper mold. Further, the two-color injection molding process can also be carried out in the individual case, when upper molds 1 and 1 ¹ are much the same or similar results.

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The invention provides that the single-colored, in the first molding device hosed injection molding, after he has the first Molding device has been removed, and after this first injection molding was freed from the upper mold 1, this injection molded part is transported to the second molding device on the stripper plate is to be subjected to a second injection by molding compound of a different color. That is why in is more beneficial It is not necessary to narrow the two upper molds to the same surface shape, on the contrary, they can be different Have shape.

It is also of particular advantage that with the aid of the method according to the invention and the associated device can not only produce the previous two-tone injection molded parts, but also injection molded parts in which individual parts such as Characters or pictorial representations have different colors, which was previously not considered possible, according to the invention, however, it is possible by appropriate design of the upper molds. Since it is also not necessary to use the upper molds to rotate, the machine is much simplified. Furthermore, an intimate closing of the mold is achieved, so that damage to the metal molds can be significantly reduced.

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Claims (1)

December 21, 1970 IG / st Katashi Aoki Claims i) Injection molding processes for the production of, in particular, two-tone ones Moldings in an injection molding machine, the two made of metal Has molding devices, characterized by the combination of the following process steps: j | A first, colored molding compound is poured into the first molding device injected, and the solidification waited until the formation of the first molded part, then the first molded part of the first Removed molding device and stored .bzw on the stripper plate. supported there, then this stripper plate offset, in particular rotated, and the one remaining on this stripper plate Injection molding introduced into the second molding device or between its upper and lower mold, this second molding device then closed and a second, differently colored molding compound is injected into the second molding device. 2. Injection molding machine to carry out the process according to * Claim 1, characterized in that it has a plate-shaped, reciprocating, in particular axially movable to and fro as well as rotatable scrapers between the upper and lower molds of the molding devices, the molded part (M) is supported during its adjustment on this plate (12) or this plate (12) carries the injection molded part. 3. A device according to Anspruoh 2, characterized in that the facing of the lower mold surface of the upper mold (1, 1 ') have different shape (1a, 1a ^1). 4. Apparatus according to claim 2 or 3, characterized in that η 2063Ö50 that a stop (1O, 10 ^f ) for the axial limitation of the stripper plate (12), in particular on the guide ^{rods (9, 9 1} ) of a support plate (4) of the upper molds (1, 1 ·) is present. 5. Device according to one of claims 2-4, characterized in that that the shaft or axle (11) rigidly connected on one side with the stripper plate (12) has an axially elongated, with a toothed rack (17) meshing toothed wheel (16), wherein the toothed rack with the piston rod (20) of the hydraulic piston (19) is firmly connected. 6. Device according to one of claims 2-5, characterized in that the lower molds (6, 6 ¹ ) mounted immovably in a stationary manner and connected to the injection nozzles (5, 5 ¹ ), but the upper molds (1, 1 ') are axially adjustable together are. 7. Device according to one of the preceding claims, characterized in that the ^{plate (4) supporting the upper molds (1, 1 1} ) runs out in one piece via a connecting component (22) into a piston (3), the hydraulic drive of which extends the axial adjustment of the upper molds (1, 1 ') and the piston and connecting part (3, 22) have an axis (11) for receiving the rotation of the stripper plate (12). 8. Device according to one of the preceding claims, characterized in that the components (16 ¹ , 17 ', 26, 25, 25') for the rotary drive of the Abstreiferp ^ atte (12) at least partially in the support plate (4) and / or this support plate (4) with the piston (3) connecting coupling part, piston neck or the like. are stored. 1 0982 7 / 1A6 8