Method and device for monitoring temperature of tire blank before mold entering of tire vulcanizer in real time

Abstract

The invention belongs to the technical field of tire vulcanization, and particularly relates to a method and a device for monitoring the temperature of a tire blank before entering a mold in real time for a tire vulcanizer. A temperature sensor is mounted on a tire mounting hand of the vulcanizer to monitor the surface temperature of a suspended tire blank in real time, and a temperature acquisition node is triggered by using a tire mounting hand shift-in limiting contact signal; the real-time tire blank temperature is transmitted to a PLC program, the vulcanization time is automatically adjusted in combination with an embedded vulcanization time correction model, the limitation of traditional fixed point room temperature monitoring is broken through, the real tire blank temperature is directly obtained, and environment temperature difference interference is eliminated; temperature collection and transmission are automatically triggered through a tire mounting hand action node, millisecond-level response is achieved, and manual lag adjustment is replaced; and the vulcanization time is dynamically calibrated based on the actual temperature of the tire blank, so that over-vulcanization or under-vulcanization is effectively avoided, and the vulcanization uniformity and the production efficiency are synchronously improved.

Description

Technical Field

[0001] The invention belongs to the technical field of tire vulcanization, and particularly relates to a method and a device for a tire vulcanizer to monitor the temperature of a tire blank before it is put into a mold in real time. Background Art

[0002] In the rubber tire vulcanization process, the temperature of the tire before it is placed in the mold directly affects the vulcanization reaction rate. Existing technologies generally use a regionalized room temperature monitoring solution: the vulcanization workshop is divided into several areas, and a thermometer (such as an electronic automatic data acquisition type or a manual reading type) is installed at a fixed location in each area. The room temperature monitored at this location is used as the default temperature for all tires in the area. If the temperature data can be automatically transmitted to the vulcanizer PLC program, the PLC adjusts the vulcanization time according to the preset tire temperature setpoint. If manual intervention is required, the vulcanization time is manually adjusted based on the temperature of the fixed monitoring point.

[0003] This solution has the following technical problems:

[0004] Inaccurate temperature feedback: The fixed monitoring point collects the ambient room temperature instead of the actual tire temperature. The monitoring point is 3-12 meters away from the vulcanizer, resulting in a significant deviation between the monitored temperature and the actual tire temperature.

[0005] Delayed adjustment of curing time: It is impossible for humans to monitor the temperature changes of all monitoring points in real time, making it difficult to adjust the curing time in a timely manner;

[0006] Insufficient vulcanization uniformity: Temperature errors can easily lead to over-vulcanization (tire shoulder embrittlement) or under-vulcanization (insufficient crown strength), reducing tire quality consistency. Summary of the Invention

[0007] The object of the present invention is to provide a method and device for real-time monitoring of the temperature of a tire blank before it is put into a mold in a tire vulcanizer, so as to solve the problems raised in the above background technology.

[0008] To achieve the above object, the present invention adopts the following technical solution: a method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer, comprising the following steps:

[0009] Temperature sensors are installed on the left and right tire loading arms of the vulcanizer to build a real-time monitoring network for the temperature field of the tire blank before it is put into the mold; the surface temperature of the tire blank suspended on the tire loading arm is collected in real time by the temperature sensor; when the tire loading arm is transferred into the vulcanizer and contacts the limit contact switch, the temperature data collection node is triggered; the real-time tire blank temperature obtained by the temperature data collection node is transmitted to the vulcanizer PLC program; based on the real-time tire blank temperature, the vulcanization time is automatically adjusted by a vulcanization time correction model embedded in the PLC program.

[0010] Preferably, the temperature sensor is a contact thermocouple or a non-contact infrared temperature sensor.

[0011] Preferably, the contact thermocouple is installed at a distance of 15 cm from the tire mounting hand grip, with an angle of ≤60° with the tire mounting hand and a response time of ≤0.5 s.

[0012] Preferably, the infrared temperature sensor is installed 15 cm away from the tire mounting hand grip, the probe angle is adjusted to 30°-45°, the temperature measurement range is 0-100°C, the accuracy is ±1°C, and the response time is ≤0.3s.

[0013] Preferably, the vulcanization time correction model is established based on the Van't Hoff law, and its expression is: t=t1+(T1-T2)*k; wherein t is the corrected vulcanization time, t1 is the reference vulcanization time, T1 is the tire base temperature, T2 is the real-time tire temperature, and k is the temperature correction coefficient.

[0014] Preferably, the temperature correction coefficient k is calibrated to 0.06 minutes / °C through factory practice.

[0015] On the other hand, the present invention proposes a device for real-time monitoring of the temperature of a tire blank before it is put into a mold on a tire vulcanizer, comprising a vulcanizer base, a tire mounting hand lifting guide rod, a temperature sensor, a tire mounting hand and a tire mounting hand grabbing piece; wherein, the tire mounting hand grabbing piece is installed at the bottom of the tire mounting hand and is located above the vulcanizer base, the tire mounting hand is installed on the tire mounting hand lifting guide rod, and the temperature sensor is installed at the bottom of the tire mounting hand.

[0016] Technical effects and advantages of the present invention: The method and device for real-time monitoring of the temperature of a tire blank before it is put into a mold proposed by the present invention have the following advantages over the prior art:

[0017] The present invention monitors the surface temperature of the suspended tire blank in real time by installing a temperature sensor on the tire loader of the vulcanizer, and uses the tire loader to enter the limit contact signal to trigger the temperature acquisition node, transmits the real-time tire blank temperature to the PLC program, and automatically adjusts the vulcanization time in combination with the embedded vulcanization time correction model, breaking through the limitations of traditional fixed-point room temperature monitoring, directly obtaining the real temperature of the tire blank, and eliminating the interference of ambient temperature differences; automatically triggering temperature acquisition and transmission through the tire loader action node, achieving millisecond-level response, replacing manual lag adjustment; dynamically calibrating the vulcanization time based on the actual temperature of the tire blank, effectively avoiding over-vulcanization or under-vulcanization, and simultaneously improving vulcanization uniformity and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a flow chart of a method for real-time monitoring of the temperature of a tire blank before it is molded by a tire vulcanizer according to the present invention;

[0019] Figure 2 The present invention is a schematic structural diagram of a device for real-time monitoring of the temperature of a tire blank before it is put into a mold in a tire vulcanizer. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0021] Example 1

[0022] In this embodiment, the Figure 2 The device shown is a device for real-time monitoring of the temperature of a tire blank before it is put into a mold during a tire vulcanizing machine, comprising a vulcanizing machine base 1, a tire loading hand lifting guide rod 2, a temperature sensor 3, a tire loading hand 4, and a tire loading hand gripper 5;

[0023] The tire-loading handle gripper 5 is mounted on the bottom of the tire-loading handle 4 and located above the vulcanizer base 1. The tire-loading handle 4 is mounted on the tire-loading handle lifting guide rod 2, and the temperature sensor 3 is mounted on the bottom of the tire-loading handle 4. By installing a contact or infrared temperature sensor at the tire-loading handle position on the vulcanizer, the temperature is transmitted to the vulcanizer PLC program in real time.

[0024] Furthermore, the temperature sensor is a contact thermocouple or a non-contact infrared temperature sensor.

[0025] Specifically, when a contact thermocouple is selected as the temperature sensor, the installation method is: install a surface-mount thermocouple (T-type) 15 cm away from the tire mounting hand grip and at an angle of ≤60° to the tire mounting hand (up and down range of movement 0°-60°), and contact the surface of the tire blank hanging on the tire mounting hand to obtain the temperature, with a response time of ≤0.5s.

[0026] Specifically, when a non-contact infrared temperature sensor is selected as the temperature sensor, the installation method is: at a distance of 15 cm from the tire mounting hand grip, the infrared probe installation angle is adjusted to 30°-45°, and the infrared temperature sensor scans the tire blank hanging on the tire mounting hand. The temperature measurement range covers 0-100°C, the accuracy is ±1°C, the optical resolution is (20:1), and the response time is ≤0.3s.

[0027] Furthermore, the process of the vulcanizer loader grabbing the tire blank and putting it into the mold:

[0028] Lowering positioning: The tire loading arm lowers until the tire contact rod touches the tire blank, and then stops lowering;

[0029] Grab the tire blank: the tire loading hand gripper opens, grabs the tire blank, rises and pauses;

[0030] Turn into positioning: The tire loader turns into the vulcanizer and stops after reaching the limit position;

[0031] Lowering into position: The tire loader carries the tire blank down to the predetermined position in the mold and stops;

[0032] Mould closing: the upper ring descends to complete the shaping, and the tire loading gripper closes and then rises and rotates out;

[0033] Vulcanization start: The mold is closed and pressurized to start the vulcanization process.

[0034] Specifically, after the tire loading hand turns in, it contacts the limit contact switch, and the contact signal is transmitted to the PLC program. The PLC captures the tire temperature received at this node, and the temperature is fed back to the embedded vulcanization time and tire temperature correction model to automatically correct and set the tire vulcanization time.

[0035] Example 2

[0036] In this embodiment, the Figure 1 A method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer is shown, comprising the following steps:

[0037] Install temperature sensors on the left and right tire loading arms of the vulcanizer to build a real-time temperature monitoring network before the tire blank is put into the mold;

[0038] The surface temperature of the tire blank hung on the tire mounting hand is collected in real time by the temperature sensor;

[0039] When the tire loader enters the vulcanizer and contacts the limit contact switch, the temperature data collection node is triggered;

[0040] Transmitting the real-time tire temperature acquired by the temperature data acquisition node to the curing machine PLC program;

[0041] Based on the real-time green tire temperature, the vulcanization time is automatically adjusted by a vulcanization time correction model embedded in the PLC program.

[0042] Furthermore, a curing time correction model is established based on the van't Hoff law, expressed as follows: t = t1 + (T1 - T2) * k; where t is the corrected curing time, t1 is the baseline curing time, T1 is the base tire temperature, T2 is the real-time base tire temperature, and k is the temperature correction coefficient. Specifically, the temperature correction coefficient k is calibrated to 0.06 minutes / °C through factory practice.

[0043] A temperature sensor is installed on each vulcanizer tire loader to build a real-time monitoring network for the temperature field before the tire blank enters the mold. The temperature data monitored and transmitted to the vulcanizer PLC before the tire blank enters the mold (when the tire loader enters) is used as the real-time tire blank temperature.

[0044] It is worth mentioning that the current method for determining the vulcanization time in the tire industry is mainly to confirm the bubble point time (the shorter the bubble point time, the better, and the more efficient), then add the safety time and thermocouple temperature measurement to confirm the vulcanization degree. In this embodiment, a combination of the two is adopted to compare the vulcanization results of the tire blank at different temperatures; a temperature sensor is installed on the tire assembler of the vulcanizer to monitor the temperature of the tire blank, specifically as follows:

[0045] Tire blank storage location: Select 10 tire blanks of the same tire specification and pattern in advance and number them A1, A2, A3, A4, A5, A6, A7, A8, B1, and B2.

[0046] The bubble point time is confirmed for A1, A2, A3, A4, A5, A6, A7, and A8 tire blanks. Thermocouples are embedded in key internal locations of B1 and B2 tire blanks to monitor temperature changes in real time during the vulcanization process and confirm the degree of vulcanization based on the Arrhenius equation. A1, A3, A5, and A7 tire blanks are placed at fixed temperature measuring points in the workshop, and A2, A4, A6, A8, B1, and B2 tire blanks are placed in front of the vulcanizer. During this period, the tire temperature is measured until it is consistent with the storage position and stabilizes and no longer changes.

[0047] Test steps and results:

[0048] Temperature confirmation: fixed temperature measuring point temperature is 22℃, and the temperature of the tire blank in the vulcanizer is 31℃.

[0049] Bubble point time confirmation and verification: The vulcanizing machine vulcanizing time was manually adjusted from 10′00″ to 8′30″ for vulcanizing A1 and A2 tire blanks, 8′00″ for vulcanizing A3 and A4 tire blanks, 7′30″ for vulcanizing A5 and A6 tire blanks, and 7′00″ for vulcanizing A7 and A8 tire blanks, and the bubble point time of the tire blanks stored in two locations was confirmed.

[0050] Analysis and comparison of bubble point time: After the tire vulcanization was completed, holographic bubble detection and tire dissection were performed to observe the number of tiny pores per unit area. Finally, it was confirmed that the bubble point time of the tire blank at the fixed temperature measurement point was 8:00", and the bubble point time of the tire blank before the vulcanizer was 7:30.

[0051] Thermocouple temperature measurement verification: Temperature measurement equipment CMA; the vulcanization time of the B1 tire is input as 10:00" based on the temperature of the fixed temperature measurement point, and the vulcanization time of the B2 tire is input as 9:30" based on the temperature of the tire in front of the vulcanizer. The vulcanization temperature is measured separately to monitor the temperature changes inside the tire during the vulcanization process in real time and ultimately confirm the degree of vulcanization.

[0052] Analysis and comparison of the weakest rubber compound with thermocouple temperature measurement:

[0053]

[0054] Note: The degree of vulcanization of the rubber material must reach 100%.

[0055] Efficiency improvement: (10.00′-9.5′) / 10.00′*100%=5%;

[0056] The degree of vulcanization is increased by 15%-32%.

[0057] Comparative Example 1

[0058] Comparison of single machines: The fixed monitoring point temperature is 20°C. Based on this temperature, the curing time for the curing press farthest from the monitoring point should be 10 minutes. The actual tire temperature monitored by the curing press is 29°C, so the curing time should be 9.46 minutes. The efficiency difference between the two is 5.4%.

[0059] Data collection: The ambient temperature at the fixed monitoring point is maintained at 20°C. A temperature sensor is installed on the tire assembler of the vulcanizer, which is farthest from the monitoring point in this area. The tire temperature is monitored at 29°C.

[0060] Parameter correction: According to the fixed monitoring point temperature, the standard vulcanization time of 10.0 minutes is adjusted to 10.0 + (20°C - 20°C) * 0.06 = 10.0 minutes (0.06 is the tire temperature compensation coefficient);

[0061] According to the tire temperature monitored by the vulcanizer, the standard vulcanization time of 10.0 minutes is adjusted to 10.0 + (20°C - 29°C) * 0.06 = 9.46 minutes (0.06 is the tire temperature compensation coefficient, rounded off);

[0062] Efficiency improvement = (10.0-9.46) / 10.0*100% = 5.4%.

[0063] Comparative Example 2 (After all 64 tire assemblers of the vulcanizing machines in the first phase of the workshop were equipped with temperature sensors)

[0064] Comparison of production (7 days before and after installation):

[0065] Daily output / piece 1 2 3 4 5 6 7 Before installation 12589 12334 12631 12357 12303 12441 12465 After installation 13331 13547 13387 13269 13431 13459 13601

[0066] Maximum efficiency improvement = (maximum daily output after installation - minimum daily output before installation) / minimum daily output before installation

[0067] =(13601-12303) / 12303*100%=10.55%.

[0068] Minimum efficiency improvement = (minimum daily output after installation - maximum daily output before installation) / maximum daily output before installation

[0069] =(13269-12631) / 12631*100%=5.05%.

[0070] Average efficiency improvement = (output 7 days after installation - output 7 days before installation) / output 7 days before installation

[0071] =(94025-87120) / 87120*100%=7.93%.

[0072] In summary, the present invention monitors the surface temperature of the suspended tire blank in real time by installing a temperature sensor on the tire loader of the vulcanizer, and uses the tire loader to enter the limit contact signal to trigger the temperature acquisition node, transmits the real-time tire blank temperature to the PLC program, and automatically adjusts the vulcanization time in combination with the embedded vulcanization time correction model, breaking through the limitations of traditional fixed-point room temperature monitoring, directly obtaining the real temperature of the tire blank, and eliminating the interference of ambient temperature differences; automatically triggering temperature acquisition and transmission through the tire loader action node, achieving millisecond-level response, replacing manual lag adjustment; dynamically calibrating the vulcanization time based on the actual temperature of the tire blank, effectively avoiding over-vulcanization or under-vulcanization, and simultaneously improving vulcanization uniformity and production efficiency.

[0073] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer, characterized in that: The following steps are involved: Install temperature sensors on the left and right tire loading arms of the vulcanizer to build a real-time temperature monitoring network before the tire blank is put into the mold; The surface temperature of the tire blank hung on the tire mounting hand is collected in real time by the temperature sensor; When the tire loader enters the vulcanizer and contacts the limit contact switch, the temperature data collection node is triggered; Transmitting the real-time tire temperature acquired by the temperature data acquisition node to the curing machine PLC program; Based on the real-time green tire temperature, the vulcanization time is automatically adjusted by a vulcanization time correction model embedded in the PLC program.

2. The method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer according to claim 1, characterized in that: The temperature sensor is a contact thermocouple or a non-contact infrared temperature sensor.

3. The method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer according to claim 2, characterized in that: The contact thermocouple is installed at a position 15 cm away from the tire mounting hand grip, with an angle of ≤60° with the tire mounting hand and a response time of ≤0.5s.

4. The method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer according to claim 2, characterized in that: The infrared temperature sensor is installed 15 cm away from the tire mounting hand grip, the probe angle is adjusted to 30°-45°, the temperature measurement range is 0-100°C, the accuracy is ±1°C, and the response time is ≤0.3s.

5. The method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer according to claim 1, characterized in that: The curing time correction model is established based on the Van't Hoff law, and its expression is: t = t1 + (T1-T2) * k; Wherein, t is the corrected vulcanization time, t1 is the reference vulcanization time, T1 is the tire base temperature, T2 is the real-time tire base temperature, and k is the temperature correction coefficient.

6. The method for real-time monitoring of the temperature of a tire blank before it is put into a mold by a tire vulcanizer according to claim 5, characterized in that: The temperature correction coefficient k is calibrated to 0.06 minutes / °C through factory practice.

7. A device for real-time monitoring of the temperature of a tire blank before it is put into a mold on a tire vulcanizer for implementing the method according to any one of claims 1 to 6, characterized in that: It includes a vulcanizing machine base, a tire loader lifting guide rod, a temperature sensor, a tire loader and a tire loader grabber; The tire mounting hand gripping piece is installed at the bottom of the tire mounting hand and is located above the vulcanizer base. The tire mounting hand is installed on the tire mounting hand lifting guide rod. The temperature sensor is installed at the bottom of the tire mounting hand.

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