Molds for injection molding

Abstract

An injection molding die includes at least two separate mold plates, each mold plate having a core groove in which a core is attached. Each mold plate has opposing and parallel abutment sides defining a mold plate thickness, and a plurality of aligned guide bushings forming through holes, the guide bushings being adapted to allow the mold plates to slide axially relative to each other on a common guide pin in a direction perpendicular to the abutment sides of the mold plates. The guide bushings and the core groove of at least one mold plate are interconnected by one or more connecting plates, each connecting plate extending parallel to the abutment sides and having a thickness less than half the thickness of the mold plates.

Description

Background Technology

[0001] The present invention relates to an injection molding die configured for installation in an injection molding apparatus for automatically molding plastic workpieces, the injection molding die comprising, in its closed position, at least two separate templates, each template having a core groove in which a core is attached, and wherein each template has opposing and parallel abutment sides defining a template thickness, and the templates further comprising a plurality of aligned guide bushings forming through holes, the guide bushings being adapted to allow the templates to slide axially relative to each other on a common guide pin in a direction perpendicular to the abutment sides of the templates.

[0002] This type of injection molding die is known to have many different embodiments, and they are typically produced by machining various components (such as guide bushings and slots for the mold core) from a single thick steel plate.

[0003] For this type of injection molding mold, in order to reduce wear and ensure the high quality of the molded product, it is important to ensure the correct alignment of the mold core installed in the mold plate.

[0004] In this regard, for example, U.S. Patent No. 4,372,740 discloses a mold for injection molding in which mold cores are mounted in mold core slots in a template, such that they can slide and tilt in the mold core slots under the influence of hydrostatic pressure in an enclosed space arranged behind each mold core. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to provide an injection molding die with a template that allows the mold core to be correctly aligned in the mold core groove, while having a simpler construction.

[0006] According to the invention, this object is achieved by the injection molding die described in the introduction, wherein the through hole and core groove of at least one template are interconnected by one or more connecting plates, each connecting plate extending parallel to the abutment side and having a thickness less than half the thickness of the template.

[0007] Therefore, the template described herein is significantly more flexible than, for example, a template made of a single thick steel plate, and thus the template can, for example, compensate for changes in the thickness of the mold core.

[0008] In this regard, the term "mold core" is intended to cover a separate component of an injection mold that can be detached from the mold plate, especially those components that form one or more cavities of the injection mold, or, for example, mold cores that form sprues and / or runners arranged in the mold plate.

[0009] In a preferred embodiment, the through holes and core grooves of at least one template are interconnected by two spaced-apart connecting plates.

[0010] In this case, each of the two spaced-apart connecting plates forms one of the abutting sides that are opposite and parallel to each other.

[0011] Furthermore, the core groove and guide bushing can preferably extend between the two connecting plates.

[0012] In a particularly advantageous embodiment of the invention, the outer peripheries of the two spaced-apart connecting plates are at least partially connected to each other by peripheral flanges, and the peripheral flanges preferably extend perpendicularly to the opposing and parallel abutting sides.

[0013] In this case, the template is preferably formed in a closed space extending between the two spaced-apart connecting plates and the peripheral flange.

[0014] In a preferred embodiment of the invention, the template is produced as a single integral unit by additive manufacturing, and by using polymer materials to produce the template by additive manufacturing, a particularly flexible unit can be achieved.

[0015] In this case, the additive manufacturing support material used for the template is advantageously retained within the enclosed space.

[0016] When the template is made of polymer material, the core is preferably made of a metal material such as steel.

[0017] In this case, each guide bushing may also advantageously include a metal bushing mounted in a bushing slot formed as a component of the template for additive manufacturing. Attached Figure Description

[0018] Figure 1 This is a perspective view showing an injection molding mold.

[0019] Figure 2 It is shown Figure 1 A perspective cross-sectional view of an embodiment of the injection molding die of the present invention.

[0020] Figure 3 It is shown Figure 1 The second perspective cross-sectional view of an embodiment of the injection molding die shown.

[0021] Figure 4 It is shown Figure 1 and Figure 2 The image shows a perspective view of an embodiment of the injection molding die of the present invention. Detailed Implementation

[0022] Figure 1An injection molding die comprising a set of templates is shown. Many different embodiments of this type of injection molding die are known, comprising two or more templates and having different functions depending on the design of the product molded in the die. Therefore, the embodiment shown here is merely one example of the construction of such an injection molding die, wherein the templates include a clamping plate 1, a support plate 2, a runner / removal template 3, a runner plate 4, and a template 5, these components forming one side of the mold cavity shown in the figure (the other side is not shown). Those skilled in the art will readily recognize that the invention can also be applied to [other applications]. Figure 1 The template shown is an injection molding die with more or fewer templates having other functions.

[0023] The templates thus form a stack of templates, wherein each template 1, 2, 3, 4 and 5 has opposing and parallel abutting sides 14, 15, thereby defining the thickness of templates 1, 2, 3, 4 and 5.

[0024] Figure 1 Each of the templates 1, 2, 3, 4 and 5 also includes cores 6 and 7, which, in the context of this document, encompass any component that can be separated from the template, particularly components having cavities or channels for guiding molten plastic material, such as cores forming mold cavities, runners, sprues, etc.

[0025] Figure 1 The injection molding mold shown can be manufactured in a conventional manner, wherein each mold piece 1, 2, 3, 4 or 5 is made of thick steel plate.

[0026] However, according to the present invention, one or more of the injection molding templates may be made of one or more connecting plates that connect the guide bushing to the mold core groove, and wherein the connecting plate is thinner than the thickness of the injection molding template.

[0027] Furthermore, according to one embodiment of the present invention, such as Figure 2 and Figure 3 As shown, templates 1, 2, 3, and 4 are advantageously made by additive manufacturing, particularly from plastic or polymer materials. Each template 1, 2, 3, 4, and 5 includes two guide bushings 8, 9, 10, and 11, and one guide bushing on one template is aligned with a similar guide bushing on another template, so that the templates can slide axially relative to each other on a common guide pin (not shown).

[0028] Each of the templates 1, 2, 3, 4 and 5 also includes core slots 12 and 13 for releasably inserting cores 6 and 7.

[0029] according to Figure 2 and Figure 3In the embodiment of the invention shown, each mold plate 1, 2, 3, 4 and 5 includes two connecting plates 19 and 20 that connect guide bushings 8, 9, 10, 11 to mold core grooves 12 and 13. The two connecting plates 19 and 20 on each injection molding mold plate 1, 2, 3, 4 and 5 form opposing and parallel abutment surfaces 14 and 15 on the injection molding mold plate 1, 2, 3, 4 and 5.

[0030] Furthermore, the peripheries of connecting plates 19 and 20 are connected along their entire periphery by peripheral flanges 21, thereby forming a closed space together with the peripheral flanges 21. Although in Figure 2 and Figure 3 Not shown, but thus it is possible to produce injection molded templates by additive manufacturing and by keeping the support material used in the manufacturing process within the closed hollow space of the injection template, so as to provide some resistance to unwanted deformation of the connecting plates 19, 20 during use.

[0031] Figure 4 It shows Figure 2 and Figure 3 A cross-section of an alternative embodiment of template 5, wherein the periphery of the connecting plate is not through Figure 2 and Figure 3 The peripheral flanges 21 shown are interconnected. In this embodiment, a plurality of additional reinforcing flanges 22 or rods 23 extend between the two connecting plates (only one is shown in the figure). Furthermore, this cross-sectional view shows other elements, such as channels 24 adapted to guide coolant to the mold core 6, which can be produced by additive manufacturing.

Claims

1. An injection molding die configured for installation in an injection molding apparatus for automatically molding plastic workpieces, the injection molding die comprising, in its closed position, at least two separate templates, each template having a core groove in which a core is attached, and wherein each template has opposing and parallel abutment sides defining a template thickness, and the templates further comprising a plurality of aligned guide bushings forming through holes, the guide bushings being adapted to allow one of the templates to slide relative to the other axially along a direction perpendicular to the abutment sides of the template on a common guide pin, characterized in that... The guide bushing and the core groove of at least one template are interconnected by one or more connecting plates, each connecting plate extending parallel to the abutment side and having a thickness less than half the thickness of the template.

2. The injection molding die as described in claim 1, characterized in that, At least one template's through hole and core groove are connected to each other by two spaced-apart connecting plates.

3. The injection molding die as described in claim 2, characterized in that, Each of the two spaced-apart connecting plates forms one of the opposing and parallel abutting sides.

4. The injection molding die as described in claim 2, characterized in that, The core groove and guide bushing extend between the two connecting plates.

5. The injection molding die as described in claim 4, characterized in that, Multiple reinforcing flanges or rods extend between the two connecting plates.

6. The injection molding die as described in any one of claims 2 to 5, characterized in that, The outer peripheries of the two spaced-apart connecting plates are at least partially connected to each other by peripheral flanges.

7. The injection molding die as described in claim 6, characterized in that, The peripheral flange extends perpendicularly to the opposing and parallel abutting sides.

8. The injection molding die as described in claim 7, characterized in that, The template is formed in a closed space extending between the two spaced-apart connecting plates and the peripheral flange.

9. The injection molding die according to any one of claims 1 to 5, characterized in that, The template is produced as a single integral unit through additive manufacturing.

10. The injection molding die as described in claim 9, characterized in that, The injection molding die is made of polymer material.

11. The injection molding die as described in claim 8, characterized in that, The additive manufacturing support material used for the template remains within the enclosed space.

12. The injection molding die as described in claim 10, characterized in that, The additive manufacturing support material used for the template remains within the enclosed space.

13. The injection molding die as described in claim 10, characterized in that, The mold core is made of metal.

14. The injection molding die as described in claim 11, characterized in that, The mold core is made of metal.

15. The injection molding die as described in claim 12, characterized in that, The mold core is made of metal.

16. The injection molding die as described in claim 13, characterized in that, The metallic material is steel.

17. The injection molding die as described in claim 10, characterized in that, Each guide bushing includes a metal bushing installed in a bushing slot that is part of a template formed for additive manufacturing.

18. The injection molding die as described in claim 11, characterized in that, Each guide bushing includes a metal bushing installed in a bushing slot that is part of a template formed for additive manufacturing.

19. The injection molding die as described in claim 12, characterized in that, Each guide bushing includes a metal bushing installed in a bushing slot that is part of a template formed for additive manufacturing.

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