WO2010063812A1 - Device for installing plastic parts inside an injection mold - Google Patents

Abstract

The invention relates to a device for installing, or for lidding, two plastic parts inside an injection mold. The injection mold comprises a first and a second mold half, which can be opened along a plane of separation in an opening direction. A bar is disposed on at least one arm rotatably about an axis at a distance; the distance can be shifted relative to the axis by way of an adjusting device.

Description

 Device for mounting plastic parts within an injection mold

The invention is in the field of injection molds, in particular Verdeckelungsvor- directions for injection molds for producing hinged closures.

The prior art discloses capping devices (cappers) for capping hinge closures within an injection mold. In addition to embodiments that retract only after the opening of the injection mold from the side, capping devices are known, which are integrated in the injection mold. These integrated capping devices are sunk in the mold halves and remain in the injection mold when they close. An advantage of the integrated capping devices is that they allow a shorter cycle time, as can already be capped during the startup of the injection mold. In addition, much less long travel paths are necessary, which also has a positive effect on the cycle time.

US4340352 from the company Global Precision Inc. was published in 1 982 and relates to a side-by-side capping device. A connected via a hinge with a lid lower part cap is raised by a pin. Subsequently, a closing arm mounted on a slide enters from the side. This raises the cap and closes it controlled by a link disc.

WOO228622A of the company Schoettli AG was published in 2002 and concerns a device that comes into action after opening a multi-cavity injection mold. The closure bottoms are sitting on a core initially lifted only slightly out of their cavities. The closure tops (lids), which are connected to the lower part of the closure via a hinge, are completely ejected and released. For the Closing the lid, a frame is inserted between the moldings after opening the mold. On the frame arms are arranged with Seh Ii esswalzen, by means of which the closures can be closed. The device has a comparatively complicated structure.

US Pat. No. 4,440,082A to Marland MoId Inc. was published in 1 998 and relates to a capping device integrated in an injection mold. A movable part of the cavity is rotatably mounted about an axis and can be rotated to open the mold to close the cap by 1 80 °. The device has various disadvantages. On the one hand, it requires a complicated mold separation. On the other hand, the closure can not escape when closing. For this reason, this device can only be used for certain closure geometries.

EP-A 38671 2 from BVA SRL. was published in 2004 and relates to an integrated in an injection mold capping mechanism, which is integrated on curved paths. During injection molding, the capping mechanism is countersunk on one side of the mold in one of the mold levels. After opening the mold a closing rod is to be moved along a gate under the cap, this lifting and then closing. It is not clear with which mechanism and how the bar should be moved.

Toppers are known from the prior art, which are integrated into an injection mold. For each lock row, they have a locking bar mounted on the ends and rotatable about a fixed radius about an axis. The closing bar and the axis are also moved laterally by means of an externally mounted carriage parallel to the main parting plane of the injection mold. When the injection mold is closed, the closing rod is arranged in a groove. After the mold is sufficiently wide open, the closing bar is raised by turning about the axis of the groove and moved by means of the carriage under the caps of the previously released from the core side hinged closures. At- Finally, the closures are closed by rotating the closing bar about the axis. A disadvantage of these capping devices is that they have only very limited flexibility. In addition, there is a problem in that the locking bar will vibrate during fast cycles and damage the hinges or the injection mold.

An object of the invention is to show an apparatus and a method by means of which assembly operations of multi-part plastic parts is possible within an injection mold.

Another object of the invention is to show an apparatus and a method by which a very efficient Verdeckein of hinge locks is possible.

The object is solved by the invention defined in the claims.

In one embodiment, the device according to the invention serves for mounting two or more plastic parts within an injection mold with a first and a second mold half, which can be opened along a parting plane in an opening direction.

The assembly process may be, for example, a closure (hood top) of an open-molded hinge closure. In this case, a closure top (cap), which is integrally connected via a hinge with a closure lower part, placed and closed by means of the device on the closure base.

The device typically comprises a rod rotatably mounted on at least one arm at a fixed or variable distance about an axis. The device has an actuating device which serves to adjust the distance between the rod and the axle. In general, the adjustment of the distance between the axle and rod takes place instead, while the rod rotates about the axis. If necessary, a movement in the longitudinal direction of the rod can be superimposed alternatively or as a supplement. It is also possible, if necessary, to superimpose a further rotational or translational movement.

In one embodiment, the arm to which the at least one rod is attached, a linear guide, along which the rod by means of the adjusting device in the radial direction or offset from it is displaceable.

One possibility is to use one or more link plates to adjust the distance between the rod and the axle. The rod may interact directly with the link plate or be supported by rollers or rollers relative to it to minimize friction and abrasion.

In order to suspect a lifting of the rod, the rod can be pressed by a spring against the at least one link plate.

If necessary, the link plate can be made interchangeable. This makes it possible to easily adjust and optimize the movement. In contrast to the prior art, the inventive device has a much higher flexibility.

In certain assembly operations, for example when Verdeckein of hinged closures, it may be advantageous if one or more rods are arranged on a displaceable approximately parallel to the parting plane of the injection mold slide. This makes it possible, after opening the injection mold and the release of the closures to be capped, to move the rod by means of the carriage in an optimal position below the cap before the assembly process begins. Depending on the embodiment, the link discs may be arranged on the carriage and / or on one of the mold halves. Since the camshaft can be adjusted very easily and flexibly, even complicated closing procedures can be mapped.

For very dynamic processes and from a certain free length of the rod, it may be advantageous if at least one mechanical stop is present, which limits the path of the rod in at least one spatial direction in a defined position. The at least one mechanical stop can be arranged between two cavities in order to catch the rod in its end position, resp. decelerate and to avoid reverberation to the rod in its final position. Alternatively or in addition, the mechanical stop may include a damper which dampens the movement of the rod. Depending on the embodiment, at least one mechanical stop can be arranged on the carriage and / or on one of the mold halves.

If necessary, one of the rods can be equipped with a gripper which serves to manipulate the plastic parts. For example, the gripper may be formed as a protruding nose, which is at least partially suitable for guiding a plastic part. When closing with a high spout, the nose of the gripper can be designed so that it is operatively connected to the closure, respectively controlled hooks on this, in order to lift it when closing controlled by the adjustment over the spout. This actively avoids a collision.

In order to avoid the reverberation of the rod in very dynamic processes, this can be made of a lightweight and stiff material. Good results are achieved with fiber composite materials, such as carbon fibers. The rod can also be designed as a tube. In order to obtain better cooling, the interior of the tube can be provided for carrying out a cooling medium, for example compressed air. The compressed air can be directed through designated openings specifically to places that need to be additionally cooled. The invention will be explained in more detail with reference to the embodiments described in the following figures. Show it:

Fig. 1 shows a first embodiment of an inventive device in one

Injection mold from diagonally above;

Fig. 2 details of the device and the injection mold of Figure 1;

Fig. 3 The device in an enlarged view obliquely from behind in an intermediate position;

Fig. 4 The device in an enlarged view obliquely from the front in an intermediate position.

FIG. 1 shows a first embodiment of an inventive device 1 obliquely from above. Figure 2 shows the device according to Figure I _1, however, certain parts are hidden, so that the structure of the device is easier to see. In Figures 3 and 4, the device 1 is detached from an injection mold 2 and shown enlarged.

The device 1 is arranged in the interior of the injection mold 2, between a first and a second mold half 3, 4. Inside, rows of cavities 23 for making closures 6 can be seen.

The mold halves 3, 4 have moved apart so far, so that the device 1 can be used. The device 1 is designed so that it can remain inside the mold 2 even when the mold 2 is closed.

The illustrated device 1 is used for closing (Verdeckein) of hinge fasteners 5, which are arranged on a core 6 of the first mold half 3 and against this free are placed. A suitably adapted device with a correspondingly similar construction can also be provided, for example, for the assembly of multi-part components. If desired, the rod 10 or portions thereof may be integrated into one or more cavities. If necessary, the rod itself or parts attached to it can form an outer wall of a cavity. The hinge closures 5, which are shown only schematically, have a closure bottom part 7 and a closure top part 8 (cap), which are operatively connected to one another via a hinge 9. The device 1 is suitable for a variety of types of hinges and is not limited to a single hinge type.

In FIGS. 1 to 4, two rows of cavities 23 are shown in each case. For each row of cavities, a device 1 with a rod 10 is provided which runs parallel to the rows of cavities. If necessary, the rods 1 0 can also be supported between the arms 1 1, or stored to reduce the free length. As a rule, a device 1 has a rod 10 which, in the embodiment shown, is held at both ends by arms 11. The arms 1 1 in turn are on a carriage 1 2 parallel to a parting plane 14 (y-direction) of the injection mold 2 slidably disposed and rotatable about an axis 1 3. The carriage 1 2 can be moved along a guide rail 1 5. The guide rail is fixedly arranged here opposite the one half of the mold. In certain embodiments, the carriage 1 2 can be dispensed with. An adjusting device 1 6, which here comprises a cam disk 1 7, serves to displace the rod 1 0 during its rotation about the axis 1 3 in the radial direction along the arms 11. For this purpose, the ends of the rod 1 0 are held in linear bearings 1 8. The ends of the rod 1 0 are formed as a square, which avoid unwanted twisting of the rod 1 0 relative to the arms 1 1. The cams 1 7 are here fixed to the carriage 1 0 mounted. The rods 10 are pressed from outside against the cam disk 1 7 via springs 19. If necessary, an outer or an inner and an outer cam (not shown) can be used. In the figures 3 and 4, the carriage 1 2 with the adjusting device 1 6 and the rod 1 0 is shown enlarged.

Due to the shape of the cam 1 7, the distance between the rod 1 0 and the axis 1 3 (dash-dotted line) is defined depending on the angle of rotation about the axis 1 3. By adjusting the cam 1 7 can be easily optimized, the closing process. For example, it is possible to take the closure tops 8 by means attached to the rod 1 0 grippers 20 and guided on the closure bottom part 7 set. In the embodiment shown, the grippers 20 are designed as nose-shaped elements which are screwed to the rod 10. The grippers 20 are designed such that they hook into an opening of the closure top 8 and guide the closure top on a defined by the cam 1 7 way on the closure bottom part 7.

As can be seen, the cam disks 1 7 are arranged lying inside and the arms 1 1 engage between the cam 1 7 and the carriage 1 2. The drive of the arms 1 1 via a pinion 21 and a relative to the carriage 1 2 displaceable rack 22nd

In contrast to FIG. 1, in FIG. 2 the carriage 1 2 is displaced in the minus y direction, so that the rod 1 0 and the grippers 20 come to rest below the closure upper part 8. Subsequently, we moved the rack 22 relative to the slide 1 2 in the plus y direction, so that the arms 1 1 driven by the pinion 21 rotate about the axis 1 3. At a certain angle, the grippers 20 engage with the upper closure parts 8 in operative connection and conduct them over in a controlled manner from the open position into the closed position.

The movement of the rod 1 0 and the arm 1 1 to the fixed cam 1 7, and drive by means of the rack 22 and the pinion 21 are shown schematically in Figure 4 by the arrows pl, p2 and p3. By the rack 22 opposite the Schiit 1 2 is moved, the pinion 21 is driven, which transmit the movement to the on the carriage 1 2 about the axis 1 3 rotatably mounted arms 1 1. The arms 1 1 move the rod 1 0 along the fixedly arranged cam 1 7. By the spring 1 9, the rod 1 0 is pressed against the cam. As a result of the variable diameter of the cam disc 1 7, the distance of the rod 1 0 to the axis 1 3 changes as a function of the shape of the cam 1 7. An advantage of the embodiment shown is the slim and simple structure, both within an injection mold and can be arranged outside. Due to the exchangeable cam, the course can be adjusted very easily.

LIST OF REFERENCE NUMBERS

1 device

2 injection mold

3 first half of the mold

4 Second half of the mold

5 hinge closure

6 core

7 closure base

8 lock top

9 hinge

10 pole

1 1 arm

1 2 sleds

1 3 axis

14 parting plane

1 5 guide rail

1 6 adjusting device

1 7 cam

18 linear bearings

1 9 spring

20 grippers

21 pinions

22 rack

23 cavity

Claims

claims 1. An apparatus for mounting two plastic parts within an injection mold having a first and a second mold half which can be opened along a parting plane in an opening direction, with a rod rotatably mounted on at least one arm at a distance about an axis, characterized in that an adjusting device is provided which serves to adjust the distance between the rod and the axle. 2. Device according to claim 1, characterized in that the at least one arm has a linear guide along which the rod by means of the adjusting device in the radial direction or offset from it is displaceable. 3. Device according to claim 2, characterized in that the adjusting device has at least one link plate, which serves to control the distance between the rod and the axle. 4. Device according to claim 3, characterized in that the rod is pressed by means of a spring against the at least one link plate. 5. Device according to claim 3, characterized in that the at least one link plate is interchangeable. 6. Device according to one of the preceding claims, characterized in that the rod is arranged on a displaceable approximately parallel to the parting plane of the injection mold slide. 7. Device according to claim 6, characterized in that at least one link disc is arranged on the carriage. 8. Device according to one of the preceding claims, characterized in that at least one mechanical stop is present, which limits the path of the rod in at least one spatial direction in a defined position. 9. Device according to claim 8, characterized in that the at least one mechanical stop is arranged between two cavities. 10. Device according to one of the claims 8 or 9, characterized in that the at least one mechanical stop includes a mechanical damper, which dampens the movement of the rod. 1 1. Device according to one of the claims 8 to 10, characterized in that at least one mechanical stop is arranged on the carriage and / or on one of the mold halves. 12. Device according to one of the preceding claims, characterized in that at least one gripper is arranged on the rod. 13. Device according to claim 1 2, characterized in that the at least one gripper is a protruding nose which serves to guide a plastic part. 14. Device according to one of the preceding claims, characterized in that the at least one rod is made of fiber composite material. 5. Device according to one of the preceding claims, characterized in that the at least one rod is a tube.