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

Abstract

Disclosed is an insert for an injection molding nozzle, with an insert body, 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. Furthermore, the insert body has a flange projecting radially with respect to the end section, having a stopping surface facing the outlet opening and a surface facing the inlet opening. It is proposed that the neck section has at least one seal.

Claims

1. An insert for an injection molding nozzle, with an insert body 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, an end section, and a flange projecting radially with respect to the neck section and the end section, the flange having a stopping surface facing the outlet opening and a surface facing the inlet opening, wherein the neck section comprises a seal.

2. The insert as claimed in claim 1, wherein the seal is configured as a sealing ring.

3. The insert as claimed in claim 1, wherein the seal forms a positioning ring.

4. The insert as claimed in claim 1, wherein the seal has a substantially rectangular cross section.

5. The insert as claimed in claim 4, wherein the substantially rectangular cross section of the seal comprises at least one concave and/or convex formation.

6. The insert as claimed in claim 1, wherein the seal comprises at least one cutting and/or pinching edge in a longitudinal direction of the insert.

7. The insert as claimed in claim 1, wherein the seal is arranged on an outer circumference of the neck section.

8. The insert as claimed in claim 7, wherein a circumferential recess for the seal is formed in the outer circumference of the neck section.

9. The insert as claimed in claim 1, wherein the seal is arranged adjacent to the radially projecting flange.

10. The insert as claimed in claim 1, wherein the seal is in contact at least for a portion with the surface of the flange facing the inlet opening.

11. The insert as claimed in claim 10, wherein the seal stands in contact with the surface of the flange by a cutting and/or pinching edge.

12. 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 being formed substantially by the end section, and wherein the first part is made from a high thermal conductivity material and is configured to extend from the neck section of the insert body as far as a boundary surface and the second part is made from a second material, which is different from the high thermal conductivity material, wherein the second part is configured to extend 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.

13. The insert as claimed in claim 12, wherein the boundary surface extends perpendicular or obliquely to a longitudinal axis of the insert body.

14. The insert as claimed in claim 11, wherein the first part and the second part are welded together in and/or along the boundary surface.

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

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0075] 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 the drawings. There are shown:

[0076] FIG. 1 is a schematic longitudinal section through a first embodiment of an insert according to the disclosure,

[0077] FIG. 2 is a schematic longitudinal section through another embodiment of an insert according to the disclosure,

[0078] FIG. 3 is a schematic longitudinal section through another embodiment of an insert according to the disclosure,

[0079] FIG. 4 is a schematic longitudinal section through yet another embodiment of an insert according to the disclosure.

DETAILED DESCRIPTION

[0080] The insert designated generally as 1 in FIG. 1 is intended for use in an injection molding nozzle of an injection mold (not otherwise represented). The injection molding nozzle has a material tube and a heating device, while a heat conducting sleeve 6 is installed in the end of the material tube which is facing a mold insert of the injection mold. The latter accommodates the insert 1 in lengthwise movable manner in the cold state of the injection mold.

[0081] The insert 1 has an insert body 2, in which a flow channel 3 is formed with an inlet opening (not visible) and an outlet opening 4. The inlet opening stands in fluidic communication with a melt channel formed in the material tube and the heat conducting sleeve. The outlet opening 4 emergesif the injection molding nozzle is mounted in the injection molddirectly in a gate opening in the mold insert of the injection mold (also not shown).

[0082] The insert 1 moreover has a neck section 5, for introducing or inserting the insert body 2 into the injection molding nozzle, namely into the heat conducting sleeve 6, while the neck section 5 is preferably inserted or press fitted into the heat conducting sleeve 6. At its end opposite the neck section 5, the insert 1 has an end section 7. By this end section, the insert 1 is inserted into the mold insert of the injection mold.

[0083] Between the neck section 5 and the end section 7 is formed a flange 8 projecting radially with respect to the neck section 5 and the end section 7. This has a stopping surface 9, which faces the outlet opening 4, and a surface 10, which faces the inlet opening. By the stopping surface 9 the insert 1 can be braced against or on the mold insert, when the injection molding nozzle and the injection mold are mounted. The surface 10 on the flange 8 serves as a supporting surface or abutment for a seal 11, which is formed on the neck section 5 of the insert.

[0084] It can be seen in FIG. 1 that the seal 11 is arranged preferably in the lower region of the neck section 5, the lower region of the neck section 5 being formed adjacent to the radially projecting flange 8. The seal 11 sits like a closed ring on the outer circumference 51 of the neck section 5. The latter is provided with an encircling circumferential recess 52 in this region, so that the seal 11 lies in the circumferential recess 52. The latter is bounded by a step 53 in the longitudinal direction L of the insert body 2 at its end 53 facing the inlet opening of the flow channel 3, while the end of the circumferential recess 52 facing the outlet opening 4 is bounded by the flange 8 and its surface 10.

[0085] The seal 11 has a main body 12 with a substantially rectangular cross section as well as an extension 16, which is tapered relative to the rectangular cross section and by which the seal 11 is braced against the flange 8. The extension is therefore situated on the short side 17 of the rectangular cross section of the seal. In each of the long sides 15 of the rectangular cross section of the seal 11 there is produced a concave formation 14. These may be formed lying opposite each other. The formations 14 may also lie at different heights in the longitudinal direction L.

[0086] The seal 11, preferably made from a deformable material, such as a metal, thus forms at first a sealing ring for the insert 1, which seals off the insert body 2 against the heat conducting sleeve 6 when the insert 1 is inserted into the heat conducting sleeve 6 and the injection molding nozzle is mounted in the injection mold. As soon as the latter has reached its operating temperature, the main body 12 of the seal 11 and the extension 16 are deformed to such an extent that a durable reliable seal is created between the insert 1 and the heat conducting sleeve.

[0087] The extension 16 forms in this case a cutting and/or pinching edge, which is designed such in its dimensions that it is deformed by the flange edge in the plastic region. At the same time, the concave formations 14 ensure that the main body 12 of the seal 11 can also be deformed specifically between the neck section 5 of the insert body 2 and the heat conducting sleeve 6, so that a durable reliable seal is created between the insert 1 and the heat conducting sleeve 6. The heat conducting sleeve 6 is not damaged in this process, since the extension 16 cuts only into the flange 8 of the insert body 1.

[0088] The sealing ring thus creates a durable reliable seal in the insulation region of the injection molding nozzle, i.e., the plastic being processed or its components can no longer get through between the insert 1 and the heat conducting sleeve 6 to the outside and into the forechamber regionfilled or unfilled depending on the area of applicationof the injection molding nozzle. The insert 1 thus not only protects against wear during the processing of abrasive media, but also ensures a durable reliable sealing.

[0089] Yet the seal forms not only a sealing ring, but also a positioning ring.

[0090] Once the injection mold has reached its operating temperature, the seal 11 forms with its main body 12 and the extension 16 a defined end stop between the flange 8 and the heat conducting sleeve 6. The seal 11 in this process is braced by the extension 16 inside the circumferential recess 52 against the surface 10 of the flange 8. The insert 1 thus can no longer be moved inadvertently in the direction of the material tube. Instead, it forms a defined end stop for the injection molding nozzle relative to the mold insert of the injection mold, wherein the insert 1 is positioned always flush with the surface of the article being molded. This effectively prevents unwanted overhangs at the boundary surface of the article.

[0091] The seal 11 thus ensures an always exact positioning of the insert 1 and thus the injection molding nozzle in the mold.

[0092] It may be provided that the insert 1 in the region of the extension 16 has an indentation 18 adapted to the extension 16, into which the extension 16 can be pressed when installed in an injection molding nozzle 6. In this way, the sealing effect can be further enhanced, as can the precision of the positioning.

[0093] FIG. 2 shows another embodiment of an insert 1 with a seal 11 on the neck section 5.

[0094] The seal 11 also here has a main body 12 with a substantially rectangular cross section as well as an extension 16, which is tapered relative to the rectangular cross section and by which the seal 11 is braced against the flange 8. The extension is situated on the short side 17 of the rectangular cross section of the seal.

[0095] By contrast with the embodiment of FIG. 1, however, no concave formations 14 are made in the long sides 15 of the rectangular cross section of the seal 11. Convex formations 19 are provided on the long sides 15. These may be formed opposite each other. The elevations 19 may also lie at different heights in the longitudinal direction L.

[0096] The seal 11, preferably made from a deformable material, such as a metal, thus forms a sealing ring for the insert 1, which seals the insert body 2 against the heat conducting sleeve 6 when the insert 1 is installed in the heat conducting sleeve 6 and the injection molding nozzle is mounted in the injection mold. Once this has reached its operating temperature, the main body 12 of the seal 11 with the formations 19 and the extension 16 are deformed to such an extent that a durable reliable sealing is produced between the insert 1 and the heat conducting sleeve.

[0097] The extension 16 forms in this case a cutting and/or pinching edge, which is designed such in its dimensions that it is deformed by the flange edge in the plastic region. The latter also holds for the formations 19, which are pressed with an increased force against the neck section 5 and the heat conducting sleeve 6.

[0098] At the same time, the sealing ring 11 here also forms a positioning ring, which holds the insert 1 in a defined position with respect to the heat conducting body 6.

[0099] FIG. 1 and FIG. 2 both show embodiments in which the insert 1 is installed in an injection molding nozzle, with the insert 1 sitting in a heat conducting sleeve 6. But the insert may also be inserted directly into the material tube or into a nozzle mouthpiece of the injection molding nozzledepending on the application and the design of the injection molding nozzle. In this case, the neck section 5 preferably sits with slight movement play in the injection molding nozzle.

[0100] Alternatively, it is also possible to configure the insert 1, especially the neck section, so that it is placed on an outer circumference of the heat conducting sleeve 6. The same holds for the mounting of the insert 1 directly on the material tube or on a nozzle mouthpiece.

[0101] For the receiving of the seal 11 in the heat conducting sleeve 6 there is provided a recess 22, whose inner wall (not otherwise indicated) forms a sealing surface.

[0102] This recess 22 is preferably adapted to the seal 11 or the sealing ring 12. Thus, the recess 22 may be formed as an encircling ring with a substantially rectangular cross section.

[0103] FIGS. 3 and 4 each show a longitudinal section through another preferred embodiment of an insert 1. In both FIGS. 3 and 4, the insert body 2 is two-piece. The insert body 2 comprises a first part 23 and a second part 24. The first part 23 is formed substantially by the neck section 5 and the second part 24 is formed substantially by the end section 7. It is preferable for the first part 23 to be made from a high thermal conductivity material and to extend across the neck section 5 of the insert body 2 as far as a boundary surface 25. The second part 24 is made from a second material and extends from the boundary surface 25 across the end section 7 of the insert body 2. The two parts 23, 24 are joined together in and/or along the boundary surface 25.

[0104] FIG. 3 shows that the boundary surface 25 extends between the first part 23 and the second part 24 perpendicular to the longitudinal axis L of the insert body 2.

[0105] FIG. 4 shows an alternative configuration of the boundary surface 25. Here, the boundary surface 25 extends between the first part 23 and the second part 24 obliquely to the longitudinal axis L of the insert body 2.

[0106] All features and advantages emerging from the claims, the specification, 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

[0107] 1 Insert [0108] 2 Insert body [0109] 3 Flow channel [0110] 4 Outlet opening [0111] 5 Neck section [0112] 51 Outer circumference [0113] 52 Circumferential recess [0114] 53 End [0115] 54 End [0116] 6 Heat conducting sleeve [0117] 7 End section [0118] 8 Flange [0119] 9 Stopping surface [0120] 10 Surface [0121] 11 Seal [0122] 12 Sealing ring [0123] 13 Depression [0124] 14 Concave formation [0125] 15 Long sides of seal 11 [0126] 16 Extension/cutting/pinching edge [0127] 17 Short side of seal 11 [0128] 18 Indentation [0129] 19 Convex formation [0130] 22 Recess [0131] 23 First part [0132] 24 Second part [0133] 25 Boundary surface [0134] L Longitudinal axis of insert 1