Insert for Use in an Injection Molding Nozzle and Injection Molding Nozzle with Such an Insert

Abstract

The disclosure relates to an insert for use in an injection molding nozzle, with an insert body at least made from a high thermal conductivity material, in which at least one flow channel is formed with an inlet opening and an outlet opening, wherein the insert body comprises a neck section, for joining to the injection molding nozzle, an end section, for inserting into a mold cavity of a mold insert, and a flange with a stopping surface projecting radially with respect to the end section, wherein the stopping surface is formed on a surface of the radially projecting flange facing the outlet opening. According to the disclosure, the stopping surface and the end section have at least partly an outer coating made of a second material with a low thermal conductivity.

Claims

1. An insert for use in an injection molding nozzle, with an insert body made from at least one high thermal conductivity material, in which at least one flow channel is formed with an inlet opening and an outlet opening, wherein the insert body comprises a neck section, for joining to the injection molding nozzle, an end section, for inserting into a mold cavity of a mold insert, and a flange with a stopping surface projecting radially with respect to the end section, wherein the stopping surface is formed on a surface of the radially projecting flange facing the outlet opening, wherein the stopping surface and the end section have at least partly an outer coating made of a second material with a low thermal conductivity.

2. The insert as claimed in claim 1, wherein the second material with a low thermal conductivity comprises a ceramic material.

3. The insert as claimed in claim 1, wherein the second material with a low thermal conductivity comprises zirconium oxide.

4. The insert as claimed in claim 1, wherein the end section has an end face, in which the outlet opening is recessed, the outer coating of a second material with a low thermal conductivity ending before the end face.

5. The insert as claimed in claim 1, wherein the outer coating of the end section and/or the stopping surface is arranged in a recess of the end section and/or the stopping surface, so that the end section and/or the stopping surface made of the high thermal conductivity material and the outer coating made of a second material form a flat outer surface at a boundary surface between the two materials.

6. The insert as claimed in claim 1, wherein the flange has a thread on a radially outer surface.

7. The insert as claimed in claim 1, wherein the insert body is two-piece, the first part being formed substantially by the neck section and the second part substantially by the end section, and wherein the first part is made from a high thermal conductivity material and extends from the neck section of the insert body as far as a boundary surface and the second part is made from a third material, which is different from the high thermal conductivity material, wherein the second part extends from the boundary surface as far as the end section of the insert body, and wherein the first part and the second part are joined to each other in and/or along the boundary surface.

8. The insert as claimed in claim 7, wherein the boundary surface extends perpendicular to or obliquely to the longitudinal axis of the insert body.

9. The insert as claimed in claim 1, wherein the end section with the outer coating is designed to form at least one sealing surface with the mold insert along an outer circumference.

10. An injection molding nozzle for an injection mold with an insert as claimed in claim 1.

11. The injection molding nozzle as claimed in claim 10 with a material tube in which at least one flow channel is formed, which is fluidically connected to the mold cavity of the injection mold formed by the mold insert, wherein the insert can be arranged at the end of the material tube on the mold insert side.

12. The injection molding nozzle as claimed in claim 11, wherein the injection molding nozzle has a heat conducting sleeve, at whose end on the mold insert side the insert can be arranged.

13. The injection molding nozzle as claimed in claim 12, wherein the insert is designed to be lengthwise movable in relation to the material tube, a nozzle mouthpiece or the heat conducting sleeve and the mold insert and during the operation of the injection molding nozzle it is clamped between the material tube and the mold insert, the nozzle mouthpiece and the mold insert or between the heat conducting sleeve and the mold insert.

14. The injection molding nozzle as claimed in claim 13, wherein the neck section of the insert is form fitted at least for a portion to the material tube, the nozzle mouthpiece or the heat conducting sleeve and the end section with the outer coating is form fitted at least for a portion to the mold insert.

15. The injection molding nozzle as claimed in claim 13, wherein the neck section of the insert has a higher coefficient of thermal expansion than the material tube and/or the nozzle mouthpiece and/or the heat conducting sleeve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Further features, details and benefits of the invention will emerge from the wording of the claims as well as the following description of sample embodiments with the aid of drawings. There are shown:

[0065] FIG. 1 illustrates a schematic longitudinal section through a first embodiment of an insert according to the disclosure,

[0066] FIG. 2 illustrates a schematic longitudinal section through another embodiment of an insert according to the disclosure,

[0067] FIG. 3 illustrates another schematic view of an embodiment of an insert according to the disclosure,

[0068] FIG. 4 illustrates a schematic longitudinal section through another embodiment of an insert according to the disclosure,

[0069] FIG. 5 illustrates a schematic longitudinal section through another embodiment of an insert according to the disclosure with a two-piece insert body and

[0070] FIG. 6 illustrates a schematic longitudinal section through another embodiment of an insert according to the disclosure with a two-piece insert body.

DETAILED DESCRIPTION

[0071] When working with thermosetting plastics and elastomers, where the plastic hardens under temperature influence, cold-channel systems are used accordingly in place of hot-channel systems. Therefore, when hot-channel systems are described in the following, cold-channel systems are also always meant accordingly, depending on the application.

[0072] FIGS. 1 and 2 show a longitudinal section through an insert 1 according to the disclosure for an injection molding nozzle (not shown). The insert 1 is formed by a corresponding insert body 2 made from a high thermal conductivity material. Here, the insert body 2 comprises a neck section 3, a flange 4 and an end section 5. The insert body 2 can be joined by its neck section 3 to an injection molding nozzle, for example by inserting it into or placing it on the injection molding nozzle. The flange 4 projects radially with respect to the neck section 3 and the end section 5. The end section 5 can be inserted into a mold cavity of a mold insert (not shown) and is preferably adapted to the shape of the mold cavity. Furthermore, the insert body 2 has at least one flow channel 6 with an inlet opening 7 and an outlet opening 8. The end section 5 and a stopping surface 9 of the flange 4 have an outer coating 10 made from a second material with a low thermal conductivity, the stopping surface 9 being the surface of the flange 4 facing the outlet opening 8.

[0073] The insert body 2 is preferably rotationally symmetrical about a longitudinal axis L of the insert 1. The insert body 2 is preferably formed as a single piece with neck section 3, flange 4 and end section 5.

[0074] FIG. 2 shows a preferred embodiment, where the coating 10 made from a material with a low thermal conductivity ends before an end face 11 of the end section 5. The end face 11 of the end section 5 is the surface in which the outlet opening 8 is made and which is in connection with a gate opening of a mold insert. In this way, a boundary region between the two different materials of the insert body 2 and the coating 10 at the end face 11 is avoided, which would be subjected to an intensified mechanical loading.

[0075] It is furthermore preferred that the coating 10 is arranged in a recess 12 in the outer side of the end section 5. The stopping surface 9 of the flange 4 can also have such a recess 12, not being shown here. Through this recess 12, a form fitting connection can be achieved between the insert body 2 and the coating 10. The coating 10 made from a material with a low thermal conductivity and the insert body 2 made from a high thermal conductivity material have a flat outer surface, which stands up to mechanical stresses. In particular, the boundary region between the two different materials has a flat outer surface, so that no edge is exposed. Furthermore, the coating 10 and the end section 5 as well as the stopping surface 9 are joined together by a contact surface 13.

[0076] The flange 4 can preferably have a thread (not shown) on its radially outer surface 13, by which the insert 1 can be easily inserted into the injection molding nozzle and removed from it.

[0077] FIG. 3 shows a perspective view of the embodiment of an insert 1 according to the disclosure, as described in FIG. 2.

[0078] FIG. 4 shows an alternative embodiment of an insert 1 according to the invention, wherein the coating 10 besides the outer side of the end section 5 and the stopping surface 9 also covers the end face 11 of the end section 5. In this embodiment, the coating 10 has an outlet opening 8 on the end face 11 of the end section 5, from which the molten material emerges. Thanks to this design, no boundary surface is formed between two materials at the end face 11, which might result in a peeling off of the coating 10.

[0079] FIGS. 5 and 6 in each case show a longitudinal section through another preferred embodiment of an insert 1 according to the disclosure. In both FIGS. 5 and 6, the insert body 2 is two-piece. The insert body 2 comprises a first part 15 and a second part 16. The first part 15 is formed substantially by the neck section 3 and the second part 16 is formed substantially by the end section 5. It is preferable for the first part 15 to be made from a high thermal conductivity material and to extend across the neck section 3 of the insert body 2 as far as a boundary surface 17. The second part 16 is made from a third material and extends from the boundary surface 17 across the end section 5 of the insert body 2. The two parts 15, 16 are joined together in and/or along the boundary surface 17. The coating 10 in this embodiment is also provided on the stopping surface 9 of the flange 4 and at least in portions of the end section 5.

[0080] The coating 10 of a material with a low thermal conductivity ends in the embodiment shown before an end face 11 of the end section 5. It is furthermore preferable for the coating 10 to be arranged in a recess 12 in the outside of the end section 5.

[0081] FIG. 5 shows that the boundary surface 17 extends between the first part 15 and the second part 17 perpendicular to the longitudinal axis L of the insert body 2.

[0082] FIG. 6 shows an alternative configuration of the boundary surface 17. Here, the boundary surface 17 extends between the first part 15 and the second part 17 obliquely to the longitudinal axis L of the insert body 2.

[0083] The invention is not limited to one of the embodiments described above, but rather can be modified in many ways. Thus, one may configure the insert 1 with the neck section 3as represented in FIGS. 1 to 6such that the insert 1 can be inserted by its neck section 3 optimally into the material tube, the nozzle mouthpiece or the heat conducting sleeve of the injection molding nozzle. But one may also configure the neck section 3 so that this reaches around or across the outside of the material tube, the nozzle mouthpiece or the heat conducting sleeve. It is important that the stopping surface 9 and/or at least the end section 5 has at least partially an outer coating 10 made from a second material with a low thermal conductivity, so that a thermal separation occurs between the insert 1 and the mold.

[0084] One will therefore recognize that the invention proposes an insert 1 for use in an injection molding nozzle, with an insert body 2 made from a high thermal conductivity material, in which at least one flow channel 6 is formed with an inlet opening 7 and an outlet opening 8, the insert body 2 having a neck section 3 for connecting to the injection molding nozzle, an end section 5 for inserting into a mold cavity of a mold insert, and a flange 4 projecting radially with respect to the end section 5, having a stopping surface 9, wherein the stopping surface 9 is formed on a surface of the radially projecting flange 4 facing the outlet opening 8. According to the disclosure, the stopping surface 9 and the end section 5 have at least partially an outer coating 10 made from a second material with a low thermal conductivity.

[0085] All features and advantages emerging from the claims, the description, and the drawing, including design details, spatial arrangements, and method steps, may be significant to the invention both in themselves and in the most varied of combinations.

LIST OF REFERENCE NUMBERS

[0086] 1 Insert [0087] 2 Insert body [0088] 3 Neck section [0089] 4 Flange [0090] 5 End section [0091] 6 Flow channel [0092] 7 Inlet opening [0093] 8 Outlet opening [0094] 9 Stopping surface of flange 4 [0095] 10 Coating [0096] 11 End face [0097] 12 Recess [0098] 13 Contact surface [0099] 14 Radially outer surface of flange 4 [0100] 15 First part [0101] 16 Second part [0102] 17 Boundary surface [0103] L Longitudinal axis of insert body 2