WO2019161977A1 - Method for producing mould segments of a segmented vulcanising mould for vehicle tyres and mould segment for a segmented vulcanising mould - Google Patents

Abstract

The invention relates to a method for producing mould segments (8) of a preferably segmented vulcanising mould for vehilce tyres, wherein the mould segments (8) can be joined to form a ring (13) and • - wherein each mould segment (8) has a segment back (17) facing away from the cavity (20) of the vulcanising mould, with which segment back the mould segment (8) is to be arranged in a device suitable for vehicle tyres, preferably in a segment shoe (7) of the vulcanising mould and • - wherein each mould segment (8) has a mould side (14) facing the cavity (20) of the vulcanising mould, which mould side has the negative profile of the tread and • - wherein the negative profile is created by means of a generative production method. A carrier element (16), onto which the mould side (14) facing the cavity (20) of the vulcanising mould is integrally applied by means of the generative production method, is used as the segment back (17) so as to obtain a hybrid mould segment (8). The invention further relates to a mould segment for a vulcanising mould.

Description

 description

METHOD FOR THE PRODUCTION OF FORMS SEGMENTS OF A SEGMENTED

VULCANISING FOR VEHICLE TIRE AND FORMS SEGMENT FOR A SEGMENTED VULCANISING FORM

The invention relates to a method for producing mold segments of a

Preferably, a segmented Vulkanisierform for vehicle tires, wherein the mold segments are assembled into a ring and wherein each mold segment has a cavity facing away from the Vulkanisierform segment back, with which the mold segment in a vehicle tire suitable device, preferably a segment shoe of the Vulkanisierform to arrange, and wherein each mold segment a mold side facing the cavity of the vulcanizing mold, which has the negative profile of the

Faufstreifens includes and where the negative profile by means of a generative

Build up manufacturing process.

The tire vulcanization is carried out in heating presses, in which the green tire is inserted into a suitable Vulkanisierform and vulcanized under the action of heat and pressure. The mold segments shape and heat the finned strip of the green tire and shape its furring profile. The invention relates to any type of heating press

(Device), preferably on segmented Vulkanisierformen.

Mold segments are traditionally produced by casting processes with subsequent machining or exclusively by machining.

It is also known, the complete negative profile of a Faufstreifen or individual

Elements of the tufts, such as Famellen, by generative

Manufacturing process and arrange in the traditionally manufactured molding surface. The advantage of generative manufacturing processes can be seen in particular in the time and cost-effective creation and in the freedom of the shape of the mold surfaces or individual elements of these mold surfaces.

From FR 2939714 Bl it is known to produce the entire negative profile of the Faufstreifens as a thin-walled shell by means of a generative manufacturing process and to arrange this shell in a mold segment with gegengleicher recording for this thin-walled negative profile shell. The disadvantage, however, is that the comparatively thin-walled shell tends to an intrinsic stress-induced, geometric component distortion and that it is for the custom-fit production of a complex and expensive

Post-processing required.

The invention has for its object to provide a process for the preparation of

To provide mold segments of a segmented Vulkanisierform, which is inexpensive, with which form segments with little or no

Component distortion can be produced and with which complex profile geometries can be realized.

 The invention is also based on the object to provide a corresponding mold segment and a vehicle tire available.

With regard to the method, this object is achieved according to the invention by selecting a carrier element serving as a segment back and applying the mold side together with the negative profile facing the cavity of the vulcanizing mold to this carrier element by means of the additive manufacturing process, so as to form a hybrid mold segment receives.

It is essential to the invention that one selects a suitable carrier element to which the mold side is applied by means of a generative manufacturing process. Carrier element and mold side are cohesively connected to each other and inseparable from each other and thus form a hybrid piece with respect to their production and / or their materials. Thereby, that the mold side is applied cohesively to the carrier element element and thus forms the carrier element with the mold side of a hybrid mold segment, takes the

Support plate stresses on and a disadvantageous component distortion is avoided. As a carrier element is a by conventional methods (eg. Urformen,

Forming, cutting and cutting or joining) produced semi-finished products such as a milled plate. The complete form side is made by the generative process. These include, for example, tread grooves, profile elements, specific features such as abrasion indicator, end surfaces and also arranged in the interior of the mold side structures, such as serving for bleeding structures. Therefore, this method is suitable both for the production of mold segments for trial / or

Exhibition tires as well as for production tires.

The term "mold side" is to be understood as meaning the entire volume which is applied to the carrier element by means of one or a combination of several generative methods and which faces the cavity of the mold segment in the state of the mold segment mounted in the vulcanizing mold. The mold side contains the complete negative profile of the tread with all its configurations.

In other words, at least the negative of the complete tire profile, including all tire profile and shape-relevant features, is generated generatively on the side of a conventionally produced carrier element facing the cavity of the vulcanization mold. The generatively generated material content remains permanently in the

cohesive bond with the executed as an integral Bestanteil of the hybrid segment body support element, which in the completion state of the hybrid

Segment body on the side facing away from the cavity of the vulcanization mold side is designed as a segment back.

To print the form side by means of the generative manufacturing process corresponding 3D data has been generated in advance in a known manner. It is expedient if the carrier element is made of the same material or of a material which is similar in its physical properties to the material to be generatively produced. This ensures a secure material connection and a material compatibility. For example, any metals, metal alloys, as well as plastics and other materials that are suitable for the stated use in a tire mold and a corresponding processing are suitable.

Tire mold segments, which are manufactured according to the described manufacturing way of aluminum or aluminum alloys or steel or steel alloys, can be used due to the conventionally produced tire mold segments comparable physical product properties in the existing infrastructure while maintaining standardized processes.

Titanium or a titanium alloy is likewise suitable as the building material, as a result of which good mechanical properties are obtained with a low weight of the component.

It is useful if you prefabricated the support element such that it has the shape of an approximately square plate or the shape of a contra-segment back or the final contour of a segment back and that subsequently on the

Segment back opposite surface of the mold side applies and that the carrier element in the form of a square plate or in kontumaher form of the

Segment back to obtain the final contour of the segment back post-processed. As a result, the creation of a final contour of the segment back having support element is temporally and spatially independent and separable from the generative structure of the form side. Depending on the load, the support plate can be brought before or after the generative application of the form side in the final contour as segment back, whereby the production of the mold segment is flexible.

In a specific embodiment of the invention, the surface of the carrier element lying opposite the segment back is guided flat and the mold side is brought onto the planar surface. A flat surface is according to the current state of the art for the Generative manufacturing processes of the powder bed based laser melting process necessary. This method is known, for example, under the name "Selective Laser Melting".

In an alternative embodiment of the invention, the surface of the support element lying opposite the segment back is already made as a curved surface in accordance with the curved contour of the mold side, and the mold side is brought onto this curved surface. A curved surface can be printed by means of the so-called "build-up welding" as a generative manufacturing process.

It is expedient if the volume of generated by means of generative processes

Form page is about the same size or larger than the volume of the segmented back located in the final contour.

It is expedient to finish the hybrid molding segment by machining and / or to subject the hybrid molding segment to suitable heat and surface treatment processes. Through these process steps can material and

Surface properties set and minimum form tolerances are met.

It is expedient if one selects the carrier element such that it is composed of one or more components and / or of one or more materials. For example, the support element made of steel may have an aluminum core for better thermal conductivity.

It is expedient if a fiber fusion process or a sintering process or a deposition welding process or a melting process or combinations of the aforementioned processes or other comparable processes which convert informal or shape-neutral materials into geometrically defined shape by means of chemical and / or physical processes is used as a generative process , The application of generative manufacturing techniques enables a fast, precise, resource-conserving and geometrically-restricted production of complex geometries in one hybrid material composite and in mutual use with other conventional manufacturing methods.

It is expedient if the entire mold side with all arranged on and in the mold side elements such as the negative profile, vent holes,

Abrasion indicators, snowflake symbol and venting elements by means of generative manufacturing process applies. The form side can be converted into the final state by the generative manufacturing process and substitute any subsequent introduction of described design elements and corresponding processes and process steps required for this purpose. This results in time and cost advantages as well as reduced manufacturing complexity.

It is expedient if additional alignment marks are generated during the generative manufacturing process, by means of which the hybrid mold segment is inserted into the

After treatment is to align appropriate devices. As a result, an exact and time-efficient post-processing of the mold segment is possible.

With respect to the mold segment for a segmented vulcanizing mold, the object is achieved in that it is produced according to one or more of the abovementioned method steps.

 The mold segment is characterized in that it consists of a carrier element and a mold side, wherein the mold side by means of a generative

Manufacturing process is produced and cohesive with and insoluble of the

Carrier element is connected and form a hybrid mold segment with respect to their production and / or their materials.

With respect to the vehicle tire, the object is achieved in that it is vulcanized in a Vulkanisierform with at least one aforementioned mold segment. Further features, advantages and details of the invention will now be described in more detail with reference to the schematic drawings, which illustrate embodiments.

It shows the

 Fig. 1 is a sectional view of a part of a tire vulcanization mold in the closed state;

 FIG. 2 shows a molding segment in a three-dimensional view; FIG.

 3 shows a segment ring of mold segments;

 4a to 4c, the mold segment to be produced in different steps of

inventive method.

Fig. 1 shows schematically the essential components of a conventional

Vulcanization mold or heating mold for a pneumatic vehicle tire for passenger cars. The Vulkanisierform is located within a heating press, whose components are not shown. Such a heating press usually comprises a press top and a press bottom and has the corresponding mechanisms for positioning the tire to be vulcanized, for operating the components of the vulcanization mold, for introducing the heating media and for removing the finished vulcanized tire.

The vulcanization mold is a multipart container shape with a lower heating plate 1, a lower side wall shell 2, an upper heating plate 3, an upper one

Sidewall shell 4, a lower bead ring 5 and an upper bead ring 15. Among those components of the vulcanization mold, which are moved to open and close in the vertical direction (arrow Pl), include the upper heating plate 3 with the arranged on this upper side wall shell 4. Die Vulkanisationsform also has a segment ring 6, which is usually composed of seven to eleven annular segment shoes 7, which support the shaping mold segments 8. For special molds, the number of mold segments can be 12 to 120. The segment shoes 7 are moved apart when opening the vulcanization mold radially, in the direction of the arrow P2 in Fig.l, and thus release the finished vulcanized tire. On the inside of the segment shoe 7 shown, a mold segment 8 can be seen, which forms the profiled tread of the tire. On the upper heating plate 3, a locking ring 9 is arranged, which has a beveled inner surface which cooperate with bevelled outer surfaces of the segment shoes 7 of the segment ring 6 such that when closing the vulcanization mold segment shoes 7 are moved together in the radial direction to the closed segment ring 6. In the lower heating plate 1, the upper heating plate 3 and the closing ring 9 Heizkammem 10, 11, l2a, l2b, l2c contained, in which at least one heating medium, in particular saturated steam (steam) is introduced to vulcanize the tire. In this way, the green tire (not shown) is heated from the outside via the segment shoes 7, the side wall shells 2, 4 and the bead rings 5, 15, so that this heater is commonly used as

Exterior heating is called.

A conventional bladder is not shown, which is arranged in a known manner and is pressurized with at least one heating medium under pressure to center the green tire in the form from the inside, wherein the bladder is brought into a mature Torusform. After the green tire is heated from the inside via the bladder, this type of heating is called interior heating.

FIG. 2 shows a mold segment 8 in a three-dimensional view, while FIG. 3 shows a ring 13 of mold segments 8 composed of a plurality of mold segments 8. FIGS. 4a to 4c show in different steps the mold segment 8 to be produced by the method according to the invention. FIGS. 2 to 4 will be described together below.

 The method according to the invention serves to produce shaped segments 8 of a segmented vulcanization mold for vehicle tires. Each mold segment 8 has a segment back 17 facing away from the cavity 20 of the vulcanization mold, with which the mold segment 8 can be arranged in a segment shoe 7 of the vulcanization mold of FIG. 1 is. Furthermore, each mold segment 8 a the cavity 20 of the

Vulkanisierform facing mold side 14, which the negative profile of the Faufstreifens Fig. 3. This form side 14 is by means of one or more generative

Built up manufacturing process.

 For this purpose, one chooses a 17 serving as segment back support member 16 made of steel, which is prefabricated in Fig. 4a and already has the final contour of the segment back 17. The segment back 17 opposite surface 18 is executed plan. On this flat surface 18 of the carrier element 16, the mold side 14 is applied cohesively by means of a generative manufacturing process. By way of example, selective laser melting is used as an example of generative production methods

Manufacturing method applied, see Fig. 4b. This results in a hybrid mold segment 8, wherein the segment back 17 is firmly and permanently connected to the mold side 14, see Fig. 4c. It is the entire mold surface 14 with all arranged on and in the mold side 14 elements such as the negative profile, vent holes, wear indicators, snowflake symbol and vent channels (the above elements are not shown) applied by the additive manufacturing process. Optionally, the hybrid molding segment 8 is machined and / or the hybrid molding segment 8 is subjected to suitable heat and surface treatment processes.

To the hybrid mold segment 8 optimally in the reworked devices

In addition, alignment marks (not shown) are created during the additive manufacturing process.

LIST OF REFERENCE NUMBERS

1 . lower heating plate

 2. lower side wall shell

3. upper heating plate

4. upper side wall shell

5. lower bead ring

 6. Segment ring

 7. Segment shoe

 8. Shape segment

9. locking ring

 10. lower heating chamber

 11. upper heating chamber 12a. heating chamber

l2b. heating chamber

l2c. heating chamber

 13. Ring of form segments

14. Seiteneigenes

 15. upper bead ring

 16. support element

17. segment back

 18. surface

 20. Cavity of the Yulcanisierform

Claims

claims 1. A process for the preparation of mold segments (8) of a preferably  segmented Vulkanisier form for vehicle tires, wherein the mold segments (8) to a ring (13) are joined and  wherein each mold segment (8) has a segment back (17) facing away from the cavity (20) of the vulcanization mold, with which the mold segment (8) is to be arranged in a device suitable for vehicle tires, preferably a segment shoe (7) of the vulcanization mold, and  wherein each mold segment (8) has a mold side (14) facing the cavity (20) of the vulcanizing mold, which mold includes the negative profile of the tread, and  wherein one builds the negative profile by means of a generative manufacturing process,  characterized,  in that one selects a carrier element (16) serving as a segment back (17) and that the mold side (14) with negative profile facing the cavity (20) of the vulcanization mold is cohesively applied to this carrier element (16) by means of the additive manufacturing process;  so as to obtain a hybrid shape segment (8). 2. The method according to claim 1, characterized in that one carries out the carrier element (16) made of the same material or of a material which is similar to the generative material to be produced in its physical properties, such as metals, metal alloys, plastics. 3. The method according to claim 1 or 2, characterized in that the Carrier element (16) prefabricated such that this is the shape of a square plate or the shape of a contra-segment back (17) or the final contour of a Segment back (17) and that then on the  Segment back (17) opposite surface (18) the forming side (14) applies and that the carrier element (16) in the form of a square plate or in kontumaher form the segment back (17) to obtain the final contour of  Segment back (17) reworked. 4. The method according to any one of the preceding claims, characterized in that one of the segment back (17) opposite surface (18) of the  Carrier element (16) performs plan and that one applies the mold side (14) on the flat surface (18). 5. The method according to any one of the preceding claims 1 to 3, characterized  in that the surface (18) of the carrier element (16) opposite the segment back (17) is already designed as a curved surface in accordance with the curved contour of the mold side, and that the mold surface (14) is applied to this curved surface (18). 6. The method according to claim 3, characterized in that the hybrid  Shaped segment (8) machined and / or that the hybrid  Mold segment (8) subjected to suitable heat and surface treatment method. 7. The method according to one or more of the preceding claims, characterized  characterized in that one selects the carrier element such that it is composed of one or more components and / or of one or more materials. 8. The method according to one or more of the preceding claims, characterized  in that a fibrous melt process or a sintering process or a build-up welding process is or is used as a generative process Melting processes or combinations of the aforementioned processes or other comparable processes which use informal or shape-neutral materials by means of transfer chemical and / or physical processes into a geometrically defined shape. 9. The method according to one or more of the preceding claims, characterized  characterized in that the entire mold side (14) is arranged with all the elements arranged on and in the mold side (14), such as the negative profile,  Venting bores, wear indicators, snowflake symbol by means of generative manufacturing process applies. 10. The method according to one or more of the preceding claims, characterized  characterized in that during the generative manufacturing process additional alignment marks are produced, by means of which the hybrid mold segment (8) is to be aligned in devices suitable for aftertreatment. 11. The method according to one or more of the preceding claims, characterized  characterized in that generated during the generative manufacturing process additional functional structures in generatively generated volume of the form side (14). Method according to one or more of the preceding claims, characterized in that a carrier element (16) serving as segment shoe (7) and segment back (17) is selected, and that the carrier (16) is materially bonded to the hollow space by means of the generative manufacturing process (16). 20) of the Vulkanisierform facing mold side (14) and negative profile applies, so as to obtain a hybrid segment. 12. molding segment for a segmented Vulkanisierform, characterized in that this is prepared according to one or more of the preceding claims 1 to 11. 13. A vehicle tire which is vulcanized in a vulcanizing mold with a mold segment (8) according to claim 12.