Method for determining a degree of vulcanization

Abstract

The invention relates to a method for determining a degree of vulcanization of a rubber device (2) and in particular for controlling a vulcanization device (3).

Description

The invention relates to a method for determining a degree of vulcanization of a rubber device and to a system for determining a degree of vulcanization of a rubber device.The invention is based on a method for determining a degree of vulcanization of a rubber device and in particular for controlling a vulcanization device, comprising the following steps:providing a rubber device, wherein the rubber device is provided for vulcanization by means of a vulcanization device;providing a vulcanization device, wherein the vulcanization device is provided for vulcanization of the rubber device;beginning a vulcanization process of the rubber device by means of the vulcanization device.Methods for determining a degree of vulcanization of a rubber device and in particular for controlling a vulcanization device are known from the prior art.The rubber device is in particular a vehicle tire or a conveyor belt. The vehicle tire is, for example, a passenger car vehicle tire, a truck vehicle tire or a two-wheeler vehicle tire.It is also known from the prior art that the methods known from the prior art for determining a degree of vulcanization of a rubber device and in particular for controlling a vulcanization device have the following steps:providing a rubber device, wherein the rubber device is provided for vulcanization by means of a vulcanization device;providing a vulcanization device, wherein the vulcanization device is provided for vulcanization of the rubber device;beginning a vulcanization process of the rubber device by means of the vulcanization device.In the methods known from the prior art for determining a degree of vulcanization of a rubber device and in particular for controlling a vulcanization device, it could be necessary to determine a temperature within the rubber device to be vulcanized, for example by means of a temperature measuring device. Such a temperature measurement could involve increased technical complexity and in particular could lead to an influencing of the vulcanization process itself.The methods known from the prior art for determining a degree of vulcanization of a rubber device could therefore not be designed optimally.The object of the invention is therefore to provide an improved method for determining a degree of vulcanization of a rubber device and in particular for controlling a vulcanization device.The object set according to the invention is achieved in that the method has the following further steps:providing a device for generating an alternating electromagnetic field;generating an alternating electromagnetic field by means of the device for generating an alternating electromagnetic field;providing an impedance measuring device, wherein the impedance measuring device is provided for carrying out an impedance measurement on the rubber device as a function of the alternating electromagnetic field;performing an impedance measurement on the rubber device as a function of the alternating electromagnetic field by means of an impedance measurement device;determining an impedance value, which can be assigned to the rubber device as a function of the impedance measurement, by means of the impedance measuring device;providing an evaluation device, wherein the evaluation device is provided for evaluating the impedance value;determining a degree of vulcanization of the rubber device as a function of the impedance value by means of the evaluation device.In particular, the method has the following steps:providing a device for generating an alternating electromagnetic field;generating an alternating electromagnetic field by means of the device for generating an alternating electromagnetic field;providing an impedance measuring device, wherein the impedance measuring device is provided for carrying out an impedance measurement on the rubber device as a function of the alternating electromagnetic field;performing an impedance measurement on the rubber device as a function of the alternating electromagnetic field by means of an impedance measurement device;determining an impedance value series, which can be assigned to the rubber device as a function of the impedance measurement, by means of the impedance measuring device;providing an evaluation device, wherein the evaluation device is provided for evaluating the impedance value series;determining a degree of vulcanization of the rubber device as a function of the series of impedance values by means of the evaluation device.In particular, the impedance measurement is carried out in an adjustable frequency range. Furthermore, in particular, an impedance spectrum is measured by means of the impedance measuring device. Preferably, the degree of vulcanization of the rubber device is determined in dependence on a series of impedance values. Preferably, the degree of vulcanization of the rubber device is determined by means of a model, wherein, for example, the degree of vulcanization is determined on the basis of the model as a function of the impedance spectrum and / or the series of impedance values.The background of the fact that the degree of vulcanization of the rubber device can be determined by means of the evaluation device as a function of the impedance value or the impedance value series is the fact that the electrical properties, for example the electrical conductivity and / or the electrical permittivity and / or polarization capacity of the rubber material to be vulcanized, depend on the electrochemical conditions of the constituents of the rubber material. The electrochemical conditions of the components of the rubber material depend on the degree of vulcanization. In particular, the electrochemical properties of a carbon black fraction in a silica mixture of a rubber material to be vulcanized change.A model by means of which the degree of vulcanization of the rubber device can be determined as a function of the impedance value or the series of impedance values takes into account in particular the frequency of the alternating electromagnetic field. The model may have been generated in particular on the basis of an already performed measurement or a series of measurements.In the case where the rubber device is, for example, a vehicle tire, the method is applied in particular to a tread region of the vehicle tire.Due to the fact according to the invention, according to which the method has the above-mentioned further steps, such a measurement of the degree of vulcanization and determination of the degree of vulcanization can be carried out without any influence being taken on the vulcanization of the rubber device as such. The vulcanization as such can thus be carried out undisturbed by determining the degree of vulcanization.Thus, an improved method for determining a degree of vulcanization of a rubber device and, in particular, for controlling a vulcanization device is provided.The invention further relates to a system for determining a degree of vulcanization of a rubber device and, more particularly, for controlling a vulcanization device. The system is particularly suitable for carrying out the method according to the invention.The system has, in particular, a vulcanization device, wherein the vulcanization device is provided for vulcanization of the rubber device. The system further comprises a device for generating an alternating electromagnetic field, an impedance measuring device, wherein the impedance measuring device is provided for carrying out an impedance measurement on the rubber device as a function of the alternating electromagnetic field, and an evaluation device, wherein the evaluation device is provided for evaluating an impedance value.The evaluation device is, for example, a computer device.Further advantageous embodiments of the present invention are the subject matter of the dependent claims.According to a preferred embodiment of the present method, the alternating electromagnetic field has a frequency of at least 100 kHz or a frequency of at least 100 MHz or a frequency of at least 1 GHz. Alternatively and / or additionally, the alternating electromagnetic field has a frequency which is set as a function of material characteristics of the rubber device. The frequency is adjusted, for example, after data have been input into a control unit of the device for generating the alternating electromagnetic field.According to a next preferred embodiment of the method according to the invention, the method has the following further steps:generating a first signal by means of the impedance measuring device, wherein the first signal contains information about the impedance value that can be assigned to the rubber device as a function of the impedance measurement;receiving the first signal by means of the vulcanization device;controlling the vulcanization process of the rubber device by means of a control unit of the vulcanization device in dependence on the first signal.According to a next preferred embodiment of the present invention, the method comprises the following further steps:generating the first signal by means of the impedance measuring device, wherein the first signal contains information about an impedance measurement value series which can be assigned to the rubber device as a function of the impedance measurement;receiving the first signal by means of the vulcanization device;controlling the vulcanization process of the rubber device by means of the control unit of the vulcanization device in dependence on the first signal.According to a next preferred embodiment of the present invention, the method comprises the following further steps:generating a second signal by means of the evaluation device, wherein the second signal contains information about the degree of vulcanization of the rubber device;receiving the second signal by means of the vulcanization device;controlling the vulcanization process of the rubber device by means of the control unit of the vulcanization device in dependence on the second signal.Controlling the vulcanization process of the rubber device means, in particular, that a vulcanization process carried out or continued by means of the vulcanization device can be ended or that a time duration during which the rubber device is still to be vulcanized by means of the vulcanization device can be established by means of the control unit. Controlling further means adjusting or presetting or utilizing an exemplary vulcanization temperature. In particular, the control means an increase in the temperature of the vulcanization or a decrease in the temperature of the vulcanization or, for example, a determination of a specific temperature change curve over time of the vulcanization process.According to a next preferred embodiment of the present method, an alternating electromagnetic field is continuously generated by means of the device for generating an alternating electromagnetic field and a continuous impedance measurement is carried out on the rubber device as a function of the alternating electromagnetic field by means of the impedance measuring device, wherein the degree of vulcanization of the rubber device is continuously determined as a function of the impedance value and / or the impedance measurement value series by means of the evaluation device.According to a next preferred embodiment of the present invention, an alternating electromagnetic field is generated multiple times by means of the device for generating an alternating electromagnetic field and a multiple impedance measurement is carried out on the rubber device as a function of the alternating electromagnetic field by means of the impedance measuring device, wherein the degree of vulcanization of the rubber device is determined multiple times as a function of the impedance value or the impedance value series by means of an evaluation device.According to a next preferred embodiment of the present invention, a reflection factor of an antenna of the device for generating an alternating electromagnetic field in a range is determined by means of the impedance measuring device as a function of the absolute value of the respective resonant frequency, in particular as a function of ratios of the electric field strength of the alternating electromagnetic field in a range of + / - 3 dB, for example, of the antenna and in particular at the resonant frequency of the antenna. In this case, a complex dielectric constant of the rubber device is determined as a function of the reflection factor, and the impedance value which can be assigned to the rubber device as a function of the impedance measurement is determined by means of the impedance measuring device as a function of the complex dielectric constant.Furthermore, for example, a complex dielectric constant of the rubber device is determined as a function of the reflection factor, and the series of impedance values, which can be assigned to the rubber device as a function of the impedance measurement, is determined by means of the impedance measurement device as a function of the complex dielectric constant.The background is that, during a vulcanization process, a complex dielectric constant of the rubber device or of constituents of the rubber device is changed by the process of vulcanization. This change in the complex dielectric constant influences the antenna and changes its reflection factor as a function of the degree of vulcanization. A real part of the impedance affecting the antenna thereby shifts the amplitude of a local minimum of the frequency, while an imaginary part of the resonance frequency is shifted.According to a next preferred embodiment of the present invention, the device for generating an alternating electromagnetic field and in particular an antenna of the device for generating an alternating electromagnetic field is in direct physical contact with the rubber device.According to a next preferred embodiment of the present invention, the vulcanization device comprises a control unit, wherein the control unit is provided for controlling the vulcanization device.According to a next preferred embodiment of the present invention, the device for generating an alternating electromagnetic field comprises at least one first antenna and at least one second antenna, wherein the first antenna is provided for generating an alternating electromagnetic field and the first antenna is a first linear antenna and the second antenna is provided for generating an alternating electromagnetic field and the second antenna is a second linear antenna, wherein the first antenna and the second antenna are arranged orthogonally to one another.According to the present invention, since the first antenna and the second antenna are arranged orthogonally to each other, an influence of an electromagnetic reflecting member inside the rubber device can be minimized. An example of an electromagnetically reflective element in a rubber device is, in particular, a steel cord belt of a truck vehicle tire. An influence of the belt angle of a steel cord belt on the impedance measurement is thereby minimized.According to a next preferred embodiment of the present invention, the device for generating an alternating electromagnetic field has a microstrip line formed from a flexible carrier material which is provided on one side with a metallized layer.Due to the fact according to the invention, according to which the device for generating an alternating electromagnetic field has a microstrip line, formed from a flexible carrier material, which is provided on one side with a metallized layer, the device is protected from exposure to temperature by such a flexible and temperature-resistant material during vulcanization.According to a next preferred embodiment of the present invention, the impedance measuring device has an impedance spectrometer, wherein the impedance spectrometer is provided for impedance measurement on the rubber device as a function of the alternating electromagnetic field, and wherein the device for generating an alternating electromagnetic field is connectable to the impedance spectrometer in a signal-transmittable manner by means of a coaxial cable.Further advantages, features and details, to which the invention is, however, not limited in its scope, will now be described in more detail with reference to the drawings.It shows: FIG. 1 : shows a schematic illustration of a system according to the invention.FIG. 1 schematically illustrates a system 1 according to the invention. The system 1 is provided for determining a degree of vulcanization of a rubber device 2 and in particular for controlling a vulcanization device 3. The system 1 is provided in particular for carrying out a method according to the invention. The system 1 comprises a vulcanization device 3. The vulcanization device 3 is provided for vulcanization of the rubber device 2. As shown in FIG. 1, the rubber device 2 is a vehicle tire. The vulcanization device 3 is provided in particular for vulcanization of a tread region 4 of the vehicle tire 2.The system further comprises a device 5 for generating an alternating electromagnetic field, an impedance measuring device 6, wherein the impedance measuring device 6 is provided for carrying out an impedance measurement on the rubber device 2 as a function of the alternating electromagnetic field, and an evaluation device 7, wherein the evaluation device 7 is provided for evaluating an impedance value.The vulcanization device 3 has, in particular, a control unit 8. The control unit 8 is provided for controlling the vulcanization apparatus 3.In particular, the device 5 for generating an alternating electromagnetic field has at least one first antenna 9 and at least one second antenna 10. The first antenna 9 is provided for generating an alternating electromagnetic field. The first antenna 9 is a first linear antenna. The second antenna 10 is provided for generating an alternating electromagnetic field; the second antenna 10 is a second linear antenna. In particular, the first antenna 9 and the second antenna 10 are arranged orthogonally to one another. The device 5 for generating an alternating electromagnetic field has in particular a component 11. The component 11 is formed from a flexible temperature-resistant material.In particular, the impedance measuring device 6 has an impedance spectrometer 12. The impedance spectrometer 12 is provided for impedance measurement on the rubber device 2 as a function of the alternating electromagnetic field. The device 5 for generating an alternating electromagnetic field can preferably be connected to the impedance spectrometer 12 in a signal-transferable manner by means of a coaxial cable 13.List of reference numerals (is part of the description)1 System 2 Rubber device 3 Vulcanization device 4 Tread region of a vehicle tire 5 Device for generating an alternating electromagnetic field 6 Impedance measuring device 7 Evaluation device 8 Control unit 9 First antenna 10 Second antenna 11 Component 12 Impedance spectrometer 13 Coaxial cable

Claims

Method for determining a degree of vulcanization of a rubber device (2) and in particular for controlling a vulcanization device (3), comprising the following steps: - providing a rubber device (2), wherein the rubber device (2) is provided for vulcanization by means of a vulcanization device (3); - providing a vulcanization device (3), wherein the vulcanization device (3) is provided for vulcanization of the rubber device (2); - beginning a vulcanization process of the rubber device (2) by means of the vulcanization device (3); characterized bythe further steps: - providing a device (5) for generating an alternating electromagnetic field; - generating an alternating electromagnetic field by means of the device (5) for generating an alternating electromagnetic field; - providing an impedance measuring device (6), wherein the impedance measuring device (6) is provided for carrying out an impedance measurement in an adjustable frequency range on the rubber device (2) as a function of the alternating electromagnetic field; - carrying out an impedance measurement on the rubber device (2) as a function of the alternating electromagnetic field by means of the impedance measuring device (6); - determining an impedance value, which can be assigned to the rubber device (2) as a function of the impedance measurement, by means of the impedance measuring device (6); - providing an evaluation device (7), wherein the evaluation device (7) is provided for evaluating the impedance value; - determining a degree of vulcanization of the rubber device (2) as a function of the impedance value by means of the evaluation device (7).Method according to claim 1, characterised in that the alternating electromagnetic field has a frequency of at least 100 kHz or that the alternating electromagnetic field has a frequency which is set as a function of material characteristics of the rubber device (2).Method according to one of the preceding claims, characterized bythe further steps of: - generating a first signal by means of the impedance measuring device (6), wherein the first signal contains information about the impedance value which can be assigned to the rubber device (2) as a function of the impedance measurement; - receiving the first signal by means of the vulcanization device (3); - controlling the vulcanization process of the rubber device (2) by means of a control unit (8) of the vulcanization device (3) as a function of the first signal.Method according to one of the preceding claims, characterized bythe further steps: - generating a second signal by means of the evaluation device (7), wherein the second signal contains information about the degree of vulcanization of the rubber device (2); - receiving the second signal by means of the vulcanization device (3); - controlling the vulcanization process of the rubber device (2) by means of a control unit (8) of the vulcanization device (3) as a function of the second signal.Method according to one of the preceding claims, characterized in that an alternating electromagnetic field is continuously generated by means of the device (5) for generating an alternating electromagnetic field and a continuous impedance measurement is carried out on the rubber device (2) as a function of the alternating electromagnetic field by means of the impedance measuring device (6), wherein the degree of vulcanization of the rubber device (2) is continuously determined as a function of the impedance value by means of an evaluation device (7).Method according to one of Claims 1 to 4, characterized in that an alternating electromagnetic field is generated multiple times by means of the device (5) for generating an alternating electromagnetic field, and a multiple impedance measurement is carried out on the rubber device (2) as a function of the alternating electromagnetic field by means of the impedance measuring device (6), wherein the degree of vulcanization of the rubber device (2) is determined multiple times as a function of the impedance value by means of the evaluation device (7).Method according to one of the preceding claims, characterized in that a reflection factor of an antenna (9, 10) of the device (5) for generating an alternating electromagnetic field in a region is determined by means of the impedance measuring device (6) as a function of an absolute value of the resonant frequency of the antenna (9, 10) and in particular at the resonant frequency of the antenna (9, 10), wherein a complex dielectric constant of the rubber device (2) is determined as a function of the reflection factor, and the impedance value which can be assigned to the rubber device (2) as a function of the impedance measurement is determined by means of the impedance measuring device (6) as a function of the complex dielectric constant.Method according to one of the preceding claims, characterized in that the device (5) for generating an alternating electromagnetic field and in particular an antenna (9, 10) of the device (5) for generating an alternating electromagnetic field is in direct physical contact with the rubber device (2).System (1) for determining a degree of vulcanization of a rubber device (2) and in particular for controlling a vulcanization device (3), wherein the system (1) is preferably suitable for carrying out a method according to one of the preceding claims, having a vulcanization device (3), wherein the vulcanization device (3) is provided for vulcanizing the rubber device (2), a device (5) for generating an alternating electromagnetic field, an impedance measuring device (6), wherein the impedance measuring device (6) is provided for carrying out an impedance measurement on the rubber device (2) as a function of the alternating electromagnetic field, and an evaluation device (7), wherein the evaluation device (7) is provided for evaluating an impedance value.System (1) according to the preceding claim, characterized in that the vulcanization device (3) has a control unit (8), wherein the control unit (8) is provided for controlling or for controlling the vulcanization device (3).System (1) according to Claim 9 or according to Claim 10, characterized in that the device (5) for generating an alternating electromagnetic field has at least one first antenna (9) and at least one second antenna (10), wherein the first antenna (9) is provided for generating an alternating electromagnetic field and the first antenna (9) is a first linear antenna and the second antenna (10) is provided for generating an alternating electromagnetic field and the second antenna (10) is a second linear antenna, wherein the first antenna (9) and the second antenna (10) are arranged orthogonally with respect to one another.System (1) according to one of Claims 9 to 11, characterized in that the device (5) for generating an alternating electromagnetic field has a component (11).System (1) according to one of Claims 9 to 12, characterized in that the impedance measuring device (6) has an impedance spectrometer (12), wherein the impedance spectrometer (12) is provided for an impedance measurement on the rubber device (2) as a function of the alternating electromagnetic field, and wherein the device (5) for generating an alternating electromagnetic field can be connected to the impedance spectrometer (12) in such a way that it can be transmitted by signal by means of a coaxial cable (13).

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