Device for vulcanizing a vehicle tire

Abstract

The invention relates to a device (1) for vulcanizing a vehicle tire, comprising a tire curing press (3) having a vulcanization mold (2), wherein the tire curing press (3) comprises an internal heating system (4) and an external heating system (5), wherein the internal heating system (4) comprises at least one electric heating element (6), wherein the electric heating element (6) is arranged within the closed vulcanization mold (2), and wherein the external heating system (5) is provided to heat the exterior of the vehicle tire via components of the vulcanization mold (2).

Description

[0001] 202407430

[0002] 1

[0003] Device for vulcanizing a vehicle tire

[0004] The invention relates to a device for vulcanizing a vehicle tire with a heating press having a vulcanization mold, wherein the heating press has an internal heating element and an external heating element, wherein the internal heating element has at least one electric heating element, wherein the electric heating element is arranged inside the closed vulcanization mold, and wherein the external heating element is provided to heat the outside of the vehicle tire via components of the vulcanization mold.

[0005] Furthermore, the invention relates to a method for vulcanizing a vehicle tire and to a vehicle tire.

[0006] Common tire heating presses use steam to heat the tire. The vulcanization mold and a heating bellows located inside the tire are heated with steam. The heating bellows warms the tire and presses it into the mold. The resulting condensate can collect in the lower part of the heating bellows, reducing the heat input to that area of ​​the tire. Alternatives to steam heating also exist. For example, the vulcanization molds are heated directly with electricity. The internal heating element is necessary to both press the tire into the mold and to generate the necessary heat.This is achieved using electric heating elements, in particular by means of heat transfer via dry gases, whereby the known approaches can be improved with regard to the achievable heat flow in the vehicle tire as well as with regard to the homogeneity of the heat input within the vehicle tire. Compared to heating with steam, which generates a significant portion of its heat flow through the condensation of the steam, other fluids, especially dry gases, require a considerably higher volume flow, which can be implemented within the given spatial conditions of a heating press. 202407430.

[0007] 2

[0008] Against this background, the invention is based on the objective of designing a device and a method in such a way that heating a vehicle tire with an internal heating system using electric heating elements in a heating press is provided in such a way that a particularly high and particularly homogeneous heat flow in the vehicle tire is enabled.

[0009] This problem is solved by a device according to the features of claim 1, as well as by a method and a vehicle tire according to the dependent claims. The subclaims relate to particularly advantageous embodiments of the invention.

[0010] According to the invention, a device for vulcanizing a vehicle tire is provided, comprising a heating press with a vulcanization mold. The heating press has an internal heating element and an external heating element, the internal heating element comprising at least one electric heating element. The electric heating element is arranged within the closed vulcanization mold. The external heating element is designed to heat the outer surface of the vehicle tire via components of the vulcanization mold, the electric heating element being configured such that it is subjected to heat transfer by a fluid flowing into the closed vulcanization mold for shaping the vehicle tire, the fluid flow being driven by a drive element arranged outside the vulcanization mold.

[0011] This design and arrangement of the heating element reduces heat loss, thereby enabling a particularly high and rapidly adjustable heat flow within the vehicle tire. A particularly efficient heating element positioned inside the vehicle tire is further made possible by the fact that the drive mechanism is located outside the tire, thus providing more installation space within the tire. Positioning the drive mechanism outside the tire also allows for a larger installation space, which is subject to lower temperature stress. This enables a particularly reliable 202407430

[0012] 3

[0013] Function of a drive unit that can generate a particularly high volume flow and a particularly high pressure difference, with the prevailing absolute pressures being approximately 20 bar.

[0014] A preferred embodiment provides that the drive element and the electric heating element form a circulation unit during the heating of a vehicle tire. This circulation unit is configured to repeatedly circulate the fluid flow through the drive element and the heating element during the vulcanization process. Circulating the fluid flow through the drive element and the heating element enables effective heat transfer from the heating element to the fluid and a homogeneous heat distribution within the vehicle tire. An actuator for heat distribution within the vehicle tire is therefore unnecessary. Furthermore, circulating the fluid flow allows for an energy-efficient process.

[0015] Another preferred embodiment provides that the driving means is a piston pump or a fan, in particular a blower or a ventilator. Fans enable a particularly high volume flow rate in a simple form. Piston pumps enable the generation of particularly high pressure differentials.

[0016] Another preferred embodiment provides that the fluid is water vapor and / or a dry gas, in particular nitrogen or air.

[0017] Another preferred embodiment provides that the circulation unit has an inlet and an outlet for adjusting the pressure in the circulation unit and the vehicle tire, the inlet preferably including a pressure regulator. The inlet and outlet of the circulation unit allow for simple adjustment of the pressure within the vehicle tire.

[0018] Another preferred embodiment provides that the adjustable pressure in the circulation unit is between 10 bar and 30 bar, preferably between 15 bar and 25 bar. This pressure range allows for effective integration into the 202407430

[0019] 4

[0020] Vulcanization mold pressing of the vehicle tire as well as effective heat transfer.

[0021] Another preferred embodiment provides that the adjustable temperature in the circulation unit is between 120 °C and 250 °C, preferably between 140 °C and 230 °C and more preferably between 160 °C and 210 °C.

[0022] Another preferred embodiment provides that the heating element is an inductive heating element, a radiant heater, a resistance heater, or a surface heating element. These heating elements enable particularly effective heat transfer to the fluid. The surface heating element can be designed such that it generates a volume flow and heat flow that is particularly effective for heat transfer to the vehicle tire.

[0023] Another preferred embodiment provides that the heating element has at least one outlet opening, wherein the outlet opening is designed such that a flow of fluid is formed within the vehicle tire in the circumferential direction of the vehicle tire, wherein the resulting volume flow in the circumferential direction preferably corresponds to 10%, more preferably to at least 30% and more preferably to at least 50% of the resulting volume flow through the circulation unit.

[0024] According to the invention, a method for vulcanizing a vehicle tire, preferably with a device according to the invention, is provided comprising the following steps:

[0025] - Placing the vehicle tire in an open vulcanization mold,

[0026] - Pressurizing the vehicle tire with an initial overpressure,

[0027] - Closing of the vulcanization mold,

[0028] - Applying a second overpressure to the vehicle tire to press the outer surface of the vehicle tire against the inner surfaces of the mold parts of the vulcanization mold,

[0029] - Vulcanizing the vehicle tire, wherein an electric current is converted into a heat flow within the vulcanization mold, the heat flow being 202407430

[0030] 5 is transported by means of a fluid flow in the vehicle tire, wherein the fluid flow is rubbed outside the vulcanization mold,

[0031] - Termination of vulcanization by opening the vulcanization mold and removing the vehicle tire from the vulcanization mold.

[0032] The process, by converting the electrical current into a heat flow within the vulcanization mold, enables particularly low heat losses and a particularly high and rapidly adjustable heat flow within the vehicle tire. Generating the fluid flow outside the vulcanization mold allows for a larger installation space for the heating element and the propellant, thus resulting in a particularly effective and efficient process.

[0033] A preferred embodiment provides that a fluid flow rate is generated within the vehicle tire that is greater than the fluid flow rate through the circulation unit, wherein the fluid flow rate within the vehicle tire preferably flows in the circumferential direction of the vehicle tire to at least 10%, more preferably at least 30%, and more preferably at least 50%. A circumferential flow rate of 10% means that the average circumferential flow rate has a velocity component of at least 10%. This results in a particularly homogeneous heat distribution within the vehicle tire.

[0034] According to the invention, a vehicle tire is manufactured using a device according to the invention and preferably using a method according to the invention. A vehicle tire manufactured in this way exhibits a particularly uniform vulcanization; overheating or underheating of parts of the vehicle tire, with the resulting disadvantages for the vehicle tire, is avoided.

[0035] The invention allows for numerous embodiments. To further illustrate its basic principle, one of these is shown in the drawings and described below. This is shown in 202407430.

[0036] 6

[0037] Fig. 1 shows a cross-sectional view of an area of ​​a device for vulcanizing a vehicle tire.

[0038] Figure 1 shows a device 1 for vulcanizing a vehicle tire with a heating press 3 comprising a vulcanization mold 2. The heating press 3 has an internal heating element 4 and an external heating element 5 in the form of a steam-heated chamber. The internal heating element 4 is arranged within the vulcanization mold 2 and comprises an electric heating element 6. The heating element 6 is a surface heating element with a plurality of flow-through surfaces and a plurality of outlet openings, which are designed and arranged such that the Bernoulli effect or free-jet effect generates a volume flow in the vehicle tire that is considerably larger than the volume flow through or at the heating element 6. The outlet openings are further oriented such that the fluid flow predominantly flows in the circumferential direction of the vehicle tire.

[0039] The electric heating element 6 is supplied with fluid by a drive element 7, in this case a piston pump. The piston pump is located outside the vulcanization mold 2 and is connected to the heating element 6 by means of fluid-carrying lines 8. The lines 8 have an inlet 9 and an outlet 10 through which the fluid, in this case nitrogen, is supplied to and removed from the process. Furthermore, the lines 8 are designed to allow circulation from the vehicle tire, through the piston pump, and through the heating element 6.

[0040] 202407430

[0041] 7

[0042] Reference symbol list

[0043] 1 Device

[0044] 2 Vulcanization form

[0045] 3 Heating press

[0046] 4 Interior heating

[0047] 5 Outdoor heating

[0048] 6 heating element

[0049] 7 Propulsion devices

[0050] 8 lines

[0051] 9 Inflow

[0052] 10 Procedure

Claims

202407430 8 Patent claims 1. Device (1) for vulcanizing a vehicle tire with a heating press (3) having a vulcanization mold (2), wherein the heating press (3) has an internal heating element (4) and an external heating element (5), wherein the internal heating element (4) has at least one electric heating element (6), wherein the electric heating element (6) is arranged inside the closed vulcanization mold (2), wherein the external heating element (5) is provided to heat the outside of the vehicle tire via components of the vulcanization mold (2), characterized in that the electric heating element (6) is designed such that it is subjected to heat transfer by a fluid flowing into the closed vulcanization mold (2) for shaping the vehicle tire, wherein the fluid flow can be driven by a drive means (7) arranged outside the vulcanization mold (2).

2. Device (1) according to claim 1, characterized in that the drive means (7) and the electric heating element (6) form a circulation unit when heating a vehicle tire, which is arranged to ensure that the fluid flow circulates repeatedly through the drive means (7) and the heating element (6) during a vulcanization process of a vehicle tire.

3. Device (1 ) according to claims 1 or 2, characterized in that the drive means (7) is a piston pump or a fan, in particular a blower or a ventilator.

4. Device (1) according to one of the preceding claims, characterized in that the fluid is water vapor and / or a dry gas, in particular nitrogen or air. 202407430 9 5. Device (1) according to one of the preceding claims, characterized in that the circulation unit has an inlet (9) and an outlet (10) for adjusting a pressure in the circulation unit and the vehicle tire, wherein the inlet (10) preferably has a pressure regulator.

6. Device (1) according to one of the preceding claims, characterized in that the adjustable pressure in the circulation unit is between 10 bar and 30 bar, preferably between 15 bar and 25 bar.

7. Device (1) according to one of the preceding claims, characterized in that the adjustable temperature in the circulation unit is between 120 °C and 250 °C, preferably between 140 °C and 230 °C and more preferably between 160 °C and 210 °C.

8. Device (1) according to one of the preceding claims, characterized in that the electrical heating element (6) is an inductive heating element, a heat radiator, a resistance heater or a surface heating element.

9. Device (1) according to one of the preceding claims, characterized in that the surface heating element has at least one outlet opening, wherein the outlet opening is designed such that a flow of fluid is formed within the vehicle tire in the circumferential direction of the vehicle tire, wherein the resulting volume flow in the circumferential direction preferably corresponds to 10%, more preferably to at least 30% and more preferably to at least 50% of the resulting volume flow through the circulation unit. 202407430 10 10. Method for vulcanizing a vehicle tire, preferably with a device (1) according to one of the preceding claims, comprising the following steps: - Placing the vehicle tire in an open vulcanization mold (2), - Pressurizing the vehicle tire with an initial overpressure, - Closing of the vulcanization mold (2), - Applying a second overpressure to the vehicle tire to press the outer side of the vehicle tire against the inner sides of mold parts of the vulcanization mold (2), -Vulcanizing the vehicle tire, wherein within the vulcanization mold (2) an electric current is converted into a heat flow, wherein the heat flow is conveyed by means of a fluid flow in the vehicle tire, wherein the fluid flow is rubbed outside the vulcanization mold (2), - Termination of vulcanization by opening the vulcanization mold (2) and removing the vehicle tire from the vulcanization mold (2).

11. Method according to claim 10, characterized in that a volume flow of the fluid is generated within the vehicle tire which is greater than the volume flow of the fluid through the circulation unit, wherein the volume flow of the fluid within the vehicle tire preferably flows to at least 10%, more preferably at least 30% and more preferably at least 50% in the circumferential direction of the vehicle tire.

12. Vehicle tires manufactured with a device (1) according to one of claims 1 to 9 and preferably manufactured with a method according to one of claims 10 to 11.

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