Rubber numerical control electric heating cycle vulcanizing machine and control system

Abstract

The invention discloses a rubber numerical control electric heating cycle vulcanizing machine and a control system, and relates to the technical field of rubber processing equipment, a temperature distribution image of a vulcanizing cavity is collected in real time through a thermal imager, regions are divided, the temperature interval of each region is identified, and the area is calculated. Based on the key temperature interval of the rubber material, constructing a three-stage intelligent regulation and control strategy: dynamically adjusting the heating power and the pressure compensation according to the temperature interval distribution in the heating stage; in the constant temperature stage, heating power and pressure parameters are optimized through temperature stability; in the cooling stage, pressure dynamic compensation is implemented according to the cooling rate. The system uses RFID to record technological parameters such as temperature and time of each stage of vulcanization, and realizes classified storage and regular quality detection of products through an intelligent warehouse management system. Through multi-parameter cooperative control, the energy consumption is remarkably reduced, the vulcanization uniformity of the rubber product is improved, the defective rate is reduced, and an efficient and energy-saving solution is provided for the rubber processing industry.

Description

Technical Field

[0001] The invention relates to the technical field of rubber processing equipment, in particular to a rubber numerically controlled electric heating cycle vulcanizer and a control system. Background Art

[0002] In the rubber vulcanization production process, traditional vulcanizers have many drawbacks. On the one hand, the heating element usually runs at a constant power. No matter what the internal temperature state of the vulcanizer is, the thermal power cannot be reasonably adjusted according to the stage of the heating element, resulting in a large amount of electrical energy waste. On the other hand, when applying pressure to rubber products, a unified standard is often used, ignoring the temperature difference of different parts of the rubber, resulting in inconsistent vulcanization degrees in different parts of the rubber products, seriously affecting product quality and increasing the defective rate. In addition, under the traditional production model, product quality traceability and management are difficult, and it is difficult to effectively monitor and analyze the quality changes of products during production and storage. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a rubber CNC electric heating cycle vulcanizer and control system, which solves the problems of not being able to adjust the pressure applied to different parts of the rubber according to the temperature distribution inside the vulcanizer and not being able to effectively monitor the quality of rubber products.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solutions: a rubber CNC electric heating cycle vulcanizer control system, comprising: Thermal imaging monitoring and area division module, which uses a thermal imager to monitor the temperature distribution inside the vulcanizer, divides the thermal imaging image into n areas according to the shape of the rubber product in the vulcanizer, the mold structure and the temperature field distribution, and transmits the thermal imaging image of the divided area to the temperature range recognition and area calculation module; The temperature interval recognition and area calculation module collects pixels from each area of ​​the thermal imaging image, determines the temperature interval in each area according to the color or gray value of the pixel corresponding to different temperatures, calculates the area of ​​different temperature intervals, and transmits the calculated temperature interval and area corresponding to each area of ​​the thermal imaging image to the temperature rise stage control module; The control module in the heating stage determines the key temperature range according to the characteristics of the rubber material, and adjusts the applied pressure of the area according to the alternative temperature range, general temperature range, number of alternative key temperature ranges and total area of ​​different areas; The constant temperature stage control module calculates the stability of the key temperature interval of the area within the key temperature interval, adjusts the applied pressure of the area within the key temperature interval according to the stability and the average temperature in the adjacent time period, and for the area within the non-critical temperature interval, calculates its distance from the surrounding areas within the key temperature interval, finds the pressure change of the area within the key temperature interval with the smallest distance to adjust the applied pressure; The cooling stage control module adjusts the applied pressure according to the cooling rates of the regions within the critical temperature range and the regions outside the critical temperature range.

[0005] As a further solution of the present invention, after the cooling stage control module, there is also a product management and quality monitoring module. After the rubber products are initially inspected and qualified, the product management and quality monitoring module attaches RFID tags to each rubber product, stores the rubber products in the warehouse according to the first-in, first-out storage principle. For the rubber products that have not been shipped out, an inspection cycle is set, and machine vision inspection software is used to automatically inspect the appearance of the rubber products. If it is found that the appearance of the product has changed, the key production information of the abnormal rubber product is read through a fixed RFID scanner, and the duration intervals [ai, bi] and the temperature mean sequence Temi at different stages are obtained. For the newly produced qualified rubber products, the system automatically compares the time tti used in the three vulcanization stages of the product with [ai, bi]. If tti ∈ [ai, bi], the product is marked as a product to be observed. The temperature change sequence Wai of the three vulcanization stages of the product to be observed is extracted, and the similarity Si between the sequence Wai and Temi is calculated respectively. A similarity threshold Sth is set, and the number num of those satisfying St > Sth is counted. If num >= 2, it is marked as a product requiring key attention.

[0006] As a further solution of the present invention, the area corresponding to each temperature range is calculated according to the formula Sij = Nij / k, where Nij is the number of pixel points in each temperature range, and k is the pixel-area conversion coefficient of the thermal imager.

[0007] As a further solution of the present invention, the distance dij between each temperature range in region i and the critical temperature range is calculated as dij = |Tij_min - Keymax|. If dij ∈ [dmin, dmax], it is marked as an alternative temperature range. If dij > dmax, it is marked as a general temperature range. If |Tij_max - Keymax| <= dij < dmin, it is marked as an alternative critical temperature range. If dij < |Tij_max - Keymax|, it is marked as a critical temperature range, where Keymax is the upper limit of the critical temperature range of the rubber material, dmin and dmax are distance thresholds, and Tij_min and Tij_max are the lower and upper limits of the jth temperature range in region i.

[0008] As a further solution of the present invention, the specific steps for pressure adjustment in different regions i during the heating stage are as follows: Count the numbers of alternative temperature ranges, general temperature ranges, and alternative critical temperature ranges in different regions i as num1, num2, num3, and the total areas as Sai, Sbi, Sci; If num2≠0 and num1=0, num3=0 of area i, the pressure adjustment formula is constructed according to the average value of the distance between the general temperature interval and the key temperature interval. The specific formula is as follows: Pi=P0+k1*avg(di)+k2*avg(di)^2; If num1≠0 and num2≠0, num3=0, then the pressure adjustment formula is constructed according to the ratio of the total area of ​​the alternative temperature interval to the general temperature interval. The specific formula is as follows: Pi=P0*(1+k3*(Sai / Sbi)+k4*sqrt(Sai / Sbi)); If num3≠0, when Sci / Stotali>=0.5, the applied pressure is Sbest. When Sci / Stotali<0.5, the pressure adjustment formula is constructed according to the total area of ​​the alternative key temperature interval. The specific formula is as follows: Pi=Sbest*(1-k5*(0.5-Sci / Stotali)); Among them, P0 is the current applied pressure, di is the distance between the general temperature range and the critical temperature range, avg() is the averaging function, sqrt() is the square root function, Sbest is the optimal applied pressure when the rubber is in the critical temperature range, and k1, k2, k3, k4, and k5 are pressure adjustment coefficients.

[0009] As a further solution of the present invention, in the constant temperature stage, if (area of ​​the critical temperature interval of region i / total area of ​​region i)>β, then the region is called a region within the critical temperature interval; otherwise, the region is called a region within the non-critical temperature interval, where β is the area threshold.

[0010] As a further solution of the present invention, the specific steps of adjusting the pressure of different areas i during the constant temperature stage are: Calculate the temperature stability index of the critical temperature interval for the area within the critical temperature interval , if σ>σmax and , appropriately reduce the regional pressure. The specific pressure adjustment formula is as follows: Pnew=Pcurrent*(1-h1*(σ-σmax)*( )); If σ>σmax and , the regional pressure needs to be appropriately increased. The specific pressure adjustment formula is as follows: Pnew=Pcurrent*(1+h2*(σ-σmax)*( )); For the region within the non-critical temperature range, calculate the distance dnear to the nearest region within the critical temperature range around it. If dnear <= dth, adjust its own pressure according to the pressure change amount of the region within the critical temperature range. The specific pressure adjustment formula is: Pnew = Pcurrent + h3 * △Pkey * (Scurrent / Stotal); otherwise, keep the current pressure unchanged. Among them, △Pkey is the pressure adjustment amount of the region within the critical temperature range, Scurrent is the area of the region within the current non-critical temperature range, Stotal is the total area, and Pcurrent is the current pressure of the region. 、 is the average value of the temperatures at time t and t + △t, and h1, h2, h3 are pressure adjustment coefficients.

[0011] As a further solution of the present invention, the specific steps for pressure adjustment of different regions i during the cooling stage are as follows: Calculate the cooling rate vT = (Tt + △t - Tt) / △t for each region; For the region within the critical temperature range, if vT < vTmax, the pressure needs to be increased. The specific pressure adjustment formula is Pnew = Pcurrent * (1 + h4 * (vTmax - vT)); If vT ∈ [vTmax, 0], the pressure should be appropriately reduced. The specific pressure adjustment formula is: Pnew = Pcurrent * (1 - h5 * (1 - Pp / Pr)); For the region within the non-critical temperature range, the specific pressure adjustment formula is: Pnew = Pcurrent * (1 + h6 * (vT - vTth) / vTth); Among them, vTmax is a negative number, Pp is the proportion of pixels with obvious temperature changes actually occurring within the critical temperature range, Pr is the reference value of the proportion of pixels with obvious temperature changes corresponding to occur within the critical temperature range in the ideal vulcanization state, vTth is the preset target cooling rate of the region within the non-critical temperature range, and h4, h5, h6 are pressure adjustment coefficients.

[0012] As a further solution of the present invention, focus on a specific area in the warehouse where the product is placed. This area is equipped with more intensive environmental monitoring equipment, and at the same time, increase the inspection frequency, and the inspection frequency is the minimum value in the preservation time series.

[0013] A rubber numerical control electrothermal cycle vulcanizer, which includes: The main frame structure is composed of a four-column or frame-type bracket, including an upper mold that can move up and down and a fixed lower mold. The upper mold and the lower mold are driven to close by a hydraulic or pneumatic device. A pressure sensor and a displacement sensor are set between the upper mold and the lower mold to monitor the mold deformation and pressure distribution in real time, and are linked with the temperature range recognition and area calculation modules of the control system to realize the pressure-temperature-displacement multi-parameter coordinated control; The electric heating circulation heating system includes a resistance wire or electromagnetic induction heating element embedded in the mold, a spiral coil heat transfer medium channel surrounding the mold, and an independent temperature control module. The main heating module and the auxiliary circulation module are linked by heat transfer oil or water medium circulation to achieve rapid temperature rise and uniformity control of the mold temperature, and communicate with the temperature rise stage control module, constant temperature stage control module and temperature drop stage control module of the control system to dynamically adjust the heating power; The multi-region dynamic pressure adjustment system includes multiple hydraulic cylinders or pneumatic cylinders distributed under or on the side of the mold. Each cylinder corresponds to an independent pressure adjustment unit. The pressure adjustment unit is connected to the temperature rise stage control module, the constant temperature stage control module and the temperature drop stage control module of the control system. The local pressure is dynamically adjusted based on the pressure compensation command sent by the control system to support differentiated pressure control in different areas during the vulcanization process. The thermal imaging integrated monitoring module includes a high temperature resistant infrared transparent window installed on the side or top of the mold, an electric zoom thermal imager and a mechanical arm positioning device. The thermal imager collects temperature field data of the vulcanization process in real time through the infrared window and transmits it to the thermal imaging monitoring and area division module of the control system to realize real-time monitoring of the temperature field and area division; The intelligent control interface realizes data interaction with the control system through an industrial computer or PLC, and supports the coordinated control of the electric heat circulation heating system, the multi-zone pressure dynamic adjustment system and the thermal imaging integrated monitoring module. The intelligent control interface has a built-in edge computing module, which can analyze the vulcanization parameters in real time and trigger early warnings, and work with the product management and quality monitoring modules of the control system to realize vulcanization data storage and quality traceability.

[0014] The present invention provides a rubber numerical control electric heating cycle vulcanizer and control system. Compared with the prior art, it has the following beneficial effects: (1) The present invention accurately adjusts the applied pressure according to the temperature of different parts of the rubber, so that the vulcanization degree of each part of the rubber product is more uniform, thereby improving the product quality and reducing the defective rate; (2) The present invention records detailed data of the product vulcanization process through RFID tags, and combines the warehouse management system and quality monitoring mechanism to achieve effective traceability and management of rubber product quality, timely discover potential quality problems, and reduce the quality risk of rubber products. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a block diagram of the system principle of the present invention. DETAILED DESCRIPTION

[0016] 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 described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] like Figure 1 The present invention provides a control system for a rubber numerical control electric heating cycle vulcanizer, comprising: Thermal imaging monitoring and area division module, which uses a thermal imager to conduct real-time and dynamic monitoring of the temperature distribution inside the vulcanizer; The thermal imager captures the internal image of the vulcanizer at a fixed frame rate. The frame rate setting needs to be determined according to the actual needs and change speed of the vulcanization process. For the vulcanization stage with rapid temperature changes, the frame rate can be appropriately increased to capture temperature change information more accurately. For example, when vulcanizing some special rubber materials, the temperature changes rapidly during the heating stage. At this time, the frame rate can be set to 5 frames per second, so that the temperature change details can be obtained in time. In the constant temperature stage, the temperature is relatively stable, and the frame rate can be adjusted to 2 frames per second to reduce the amount of data processing; After obtaining the thermal imaging image, the thermal imaging image is divided into n areas according to the shape of the rubber product in the vulcanizer, the mold structure and the temperature field distribution. For the shape characteristics of the rubber product, when vulcanization occurs, the heat transfer and vulcanization reaction speed of different parts are also different. For example, for rubber products in the shape of automobile tires, the tread, sidewalls and shoulders have obvious differences in shape and function. The tread is in contact with the ground and needs to withstand greater friction and pressure during actual use. Therefore, more precise temperature and pressure control is required during vulcanization, so it can be divided into one area separately; the sidewall is relatively thin and dissipates heat faster, so it can be divided into another area; the shoulder connects the tread and sidewall, and its temperature and vulcanization conditions are also different. It is unique and is divided into an area. The mold structure characteristics, mold material, thickness, and internal cooling channel layout and other factors will lead to inconsistent temperatures in different parts of the rubber product. If a part of the mold is thicker, the heat transfer is relatively slow, and the temperature rise of the rubber area corresponding to this part will also be slow. It can be divided into a separate area for key monitoring. The temperature field distribution characteristics refer to the temperature gradient and distribution law naturally formed inside the vulcanizer during the vulcanization process. By comprehensively considering these factors for regional division, rubber products and vulcanization environments can be subdivided according to temperature characteristics, and the subdivided area of ​​each thermal imaging picture is transmitted to the temperature range recognition and area calculation module.

[0018] Temperature interval recognition and area calculation module, which recognizes the temperature interval in each area and calculates the area. This process is mainly achieved with the help of image recognition algorithm. The image recognition algorithm can analyze the pixels in the thermal imaging image and determine the temperature interval in each area according to the color or gray value of the pixel corresponding to different temperatures; Accurately calculating the area of ​​the temperature interval is crucial for subsequent pressure and power adjustments. Temperature intervals of different areas have different effects on the overall vulcanization effect during the vulcanization process. A temperature interval with a larger area may have a greater impact on the overall performance of the rubber product, so more precise control is required. For example, for the tread area divided during the vulcanization of automobile tires, the image recognition algorithm is used to identify that there are three temperature intervals in the area: [100℃, 110℃], [110℃, 120℃], and [120℃, 130℃]. The number of pixels Nij in each temperature interval is counted, and combined with the pixel-area conversion coefficient k (pixel / square meter) of the thermal imager, the area corresponding to each temperature interval is calculated according to the formula Sij=Nij / k. k is an important parameter of the thermal imager. It is related to factors such as the resolution and shooting distance of the thermal imager. It needs to be accurately calibrated before use to ensure the accuracy of the area calculation. If k=100 pixels / square meter, after statistics, the number of pixels in the above three temperature intervals are 500, 800 and 300 respectively, so the areas of these three temperature intervals are 5 square meters, 8 square meters and 3 square meters respectively.

[0019] Temperature-raising stage control module, which accurately adjusts the applied pressure and heating power according to the characteristics of the rubber material and the requirements of the vulcanization process; Determine the critical temperature range [Kaymin, Keymax] of the rubber material. This range is the optimal temperature range for the rubber to undergo vulcanization reaction. Different types of rubber materials have different corresponding critical temperature ranges. For example, the critical temperature range of natural rubber may be [130℃, 150℃], while the critical temperature range of nitrile rubber may be [150℃, 170℃]; Calculate the distance dij = |Tij_min - Keymax| between each temperature range in the calculation region i and the key temperature range, and set the distance thresholds dmin and dmax. If dij ∈ [dmin, dmax], then mark this temperature range as an alternative temperature range; if dij > dmax, mark it as a general temperature range; if |Tij_max - Keymax| <= dij < dmin, mark it as an alternative key temperature range; if dij < |Tij_max - Keymax|, then mark it as a key temperature range, where dmin and dmax are distance thresholds, and Tij_min and Tij_max are the lower and upper limits of the j-th temperature range in region i. If all the temperature ranges in region i belong to the general temperature range, then the distance between the k-th general temperature range and the key temperature range is dit, t ∈ [1, m1], and calculate the average value avg(di) = sum(dit) / m1 of the distances between all general temperature ranges and the key temperature range. Construct the pressure application formula for this i region: Pi = P0 + k1*avg(di) + k2*avg(di)^2. If some of the temperature ranges in region i belong to the general temperature range and some belong to the alternative temperature range, if the total area of the alternative temperature ranges is Sai and the total area of the general temperature ranges is Sbi, construct the pressure application according to the formula Pi = P0*(1 + k3*(Sai / Sbi) + k4*sqrt(Sai / Sbi)). If region i contains alternative key temperature ranges and the area of the alternative key temperature ranges is Sci, when Sci / Stotali >= 0.5, apply the most suitable pressure Sbest corresponding to the key temperature range of this rubber material. When Sci / Stotali < 0.5, the pressure application formula is Pi = Sbest*(1 - k5*(0.5 - Sci / Stotali)), where k1, k2, k3, k4, and k5 are all pressure adjustment coefficients. After performing thermal imaging on the inside of the vulcanizer and dividing the regions, count the number M1 of general temperature ranges, the number M2 of alternative temperature ranges, and the number M3 of alternative key temperature ranges in all regions in each thermal imaging picture, and set the independent variable parameter ɑ = (M2 + M3) / M1. This parameter reflects the proportion of temperature ranges close to or in the key vulcanization state relative to the general temperature ranges in the thermal imaging picture. Adjust the heating power in real time according to this independent variable, and the specific formula is , where Q0 is the initial heating power of the heating element, and r is the heating power adjustment coefficient in the temperature rise stage. Adding the e-based function is mainly to control the situation where ɑ appears as an extreme value; For example, the three temperature intervals [100℃, 110℃], [110℃, 120℃], and [120℃, 130℃] identified in the above automobile tire tread area are calculated with their distances d1=50, d2=40, and d3=30 from the key temperature interval [130℃, 150℃], respectively. The distance thresholds dmin=15 and dmax=30 are used. The first two temperature intervals belong to the general temperature interval, and the third temperature interval belongs to the alternative temperature interval. Then the total area occupied by the general temperature interval is S bi=5+8=13 square meters, the area occupied by the alternative temperature range is Sai=3 square meters, the area ratio a1i=3 / 13≈0.23, the pressure adjustment coefficients k3=0.1, k4=0.05, P0=10, then the adjusted pressure is Pi=10*(1+0.1*0.23+0.05*sqrt(0.23))=10.47MPa, if Q0=100kW, r=0.2, ɑ=1 / 2=0.5, then the heating power Q=100.05kW.

[0020] Constant temperature stage control module, which needs to keep the temperature in the vulcanization chamber stable near the critical temperature range to ensure that the rubber products can be fully vulcanized. The temperature distribution inside the vulcanizer is continuously monitored by a thermal imager. According to the ratio of the critical temperature range area to the total area of ​​the area, the area is divided into areas within the critical temperature range and areas within the non-critical temperature range; If (area of ​​critical temperature interval / total area of ​​the region)>β, the region is called the region within the critical temperature interval; otherwise, the region is called the region within the non-critical temperature interval. The temperature stability index of the critical temperature interval of the region within the critical temperature interval is calculated. , if σ>σmax and the temperature has an upward trend, then To prevent excessive vulcanization of rubber, the regional pressure should be appropriately reduced. The specific pressure conversion formula is as follows: Pnew=Pcurrent*(1-h1*(σ-σmax)*( )); if σ>σmax and the temperature has a downward trend, then In order to ensure that the sulfidation reaction continues to proceed fully, the regional pressure needs to be appropriately increased. The specific pressure conversion formula is as follows: Pnew=Pcurrent*(1+h2*(σ-σmax)*( )); For the regions within the non-critical temperature range, calculate the distance dnear between it and the nearest region within the critical temperature range. If dnear <= dth, adjust its own pressure according to the pressure adjustment amount of the region within the critical temperature range. The specific formula is: Pnew = Pcurrent + h3 * △Pkey * (Scurrent / Stotal), where △Pkey is the pressure adjustment amount within the critical temperature range, Scurrent is the area of the region within the current non-critical temperature range, and Stotal is the total area. Otherwise, keep the current pressure unchanged; Focus on the temperature deviation of each region from the target temperature. The target temperature Ttar is the average temperature value of the critical temperature range. The actual average temperature of the critical temperature range of region i is Tiavg, and the temperature deviation △Ti = Tiavg - Ttar. The region weight is wi. Different regions have different importance for vulcanization. According to the formula Adjust the heating power; For example, taking the sidewall area of a car tire as an example, after a period of monitoring, part of this area is within the critical temperature range, and the critical temperature range is [130°C, 150°C]. The target temperature Ttar = 140°C. After calculation, the temperature stability index σ of this region within the critical temperature range is 3°C, and the set threshold σmax = 2°C. It is monitored that the temperature has an upward trend. The current pressure of this region is Pcurrent = 12 MPa, and the pressure adjustment coefficient h1 = 0.1. Since σ > σmax, to prevent over-vulcanization of the rubber, it is necessary to appropriately reduce the region pressure. The adjusted pressure is Pnew = 12 * (1 - 0.1 * (3 - 2) * 0.5) = 11.4 MPa; If there is a small region within a non-critical temperature range in the sidewall area, the distance dnear between it and the nearest region within the critical temperature range is 5, the set distance threshold dth = 8, the pressure adjustment amount △Pkey of the region within the critical temperature range is 0.6, the area Scurrent of the region within the current non-critical temperature range is 2 square meters, the total area Stotal where this region is located is 10 square meters, and the pressure adjustment coefficient h3 = 0.2. Because dnear < dth, adjust its own pressure according to the pressure adjustment amount of the region within the critical temperature range. The current pressure Pcurrent = 10 MPa, then the adjusted pressure Pnew = 10 + 0.2 * 0.6 * (2 / 10) = 10.024 MPa; If the actual average temperatures of three key temperature intervals in the sidewall region are T1avg = 151 °C, T2avg = 148 °C, and T3avg = 153 °C, and the temperature deviations are calculated as △T1 = 1 °C, T2 = -2 °C, and T3 = 3 °C, with the regional weights being w1 = 0.2, w2 = 0.3, and w3 = 0.5 respectively, and the heating power adjustment coefficient e1 = 5 kW / °C during the constant temperature stage, and the current heating power Q0 = 80 kW, then the adjusted heating power Q = 80 + 5 * (0.2 - 0.6 + 1.5) = 85.5 kW.

[0021] During the cooling stage, the regulation module continuously monitors the temperature of each region using a thermal imager and calculates the cooling rate vT = (T t+△t - T t ) / △t for each region. For the regions within the key temperature intervals, if the cooling is too fast, i.e., vT < vTmax (where vTmax is a negative number), it may cause stress concentration inside the rubber and affect the product performance. In this case, the pressure needs to be increased, and the specific pressure adjustment formula is Pnew = Pcurrent * (1 + h4 * (vTmax - vT)); when the cooling rate is within the normal range, i.e., vT ∈ [vTmax, 0], the pressure should be appropriately reduced to prevent the rubber product from deforming or the internal structure from being damaged due to excessive pressure. The specific pressure adjustment formula is: Pnew = Pcurrent * (1 - h5 * (1 - Pp / Pr)), where Pp is the proportion of pixels with significant temperature changes actually occurring within the key temperature intervals, and Pr is the reference value of the proportion of pixels with significant temperature changes corresponding to the ideal vulcanization state within the key temperature intervals; for the regions outside the key temperature intervals, Pnew = Pcurrent * (1 + h6 * (vT - vTth) / vTth), where vTth is the preset target cooling rate for the regions outside the key temperature intervals. The cooling rate of the key temperature interval in region i is vTkeyi, the target cooling rate is vTtar, the cooling rate deviation △vi = vTtari - vTkeyi, and the regional weight is wi. The specific formula for adjusting the heating power is: ; For example, for the shoulder region of an automotive tire, if the current temperature T t = 150 °C within the key temperature interval of this region and the temperature T t+10 = 130 °C after 10 minutes, then the cooling rate vT = -2 °C / min, and the cooling rate threshold vTmax = -1 °C / min, indicating that the cooling is too fast and the pressure needs to be increased. Pcurrent = 10 MPa, and the pressure adjustment coefficient h4 = 0.2. The adjusted pressure is Pnew = 10 * (1 + 0.2 * (-1 + 2)) = 12 MPa; If the cooling rate of another area vT=-0.5℃ / min, within the normal range, the current pressure Pcurrent=8MPa, the actual percentage of pixels with obvious temperature changes in the key temperature range Pp=0.6, the corresponding reference value of the percentage of pixels with obvious temperature changes in the key temperature range under ideal vulcanization conditions Pr=0.8, and the pressure adjustment coefficient h5=0.1, then the adjusted pressure is Pnew=8*(1-0.1*(1-0.6 / 0.8))=7.8MPa; If the cooling rates in the key temperature intervals of the three zones are vTkey1=-0.6℃ / min, vTkey2=-0.4℃ / min, vTkey3=-0.3℃ / min, vTtar1=-0.5℃ / min, vTtar2=-0.6℃ / min, vTtar3=-0.2℃ / min, △v1=0.1℃ / min, △v2=-0.2℃ / min, △v3=0.1℃ / min, the heating power adjustment coefficient e2=10℃ / min in the cooling stage, the current heating power Q0=60kW, and the regional weights are w1=0.7, w2=0.2, w3=0.1, Q=60*(10*(max(0.1,-0.2,-0.1,0) / (0.35+0.12+0.02)))=122kW.

[0022] Product management and quality monitoring module, which mainly manages and monitors the rubber products from production to storage. After the rubber products are vulcanized and pass the preliminary inspection, RFID tags are attached to each product. Taking automobile tires as an example, RFID tags have the advantages of large storage capacity, easy reading and writing, and reusability. They can record basic information of products, such as tire model 205 / 55R16, batch 20250305-001, and production date March 5, 2025, etc., and focus on recording detailed data of the three stages of vulcanization heating, constant temperature, and cooling. For example, it takes 20 minutes to rise from room temperature to 140°C in the heating stage, and the temperature change sequence during this period is to record the temperature every △t minutes, △t can be 1, 2,..., the constant temperature stage is maintained at 140℃-160℃ for 30 minutes, and the temperature fluctuation range is ±2℃. It takes 40 minutes to drop from 160℃ to room temperature in the cooling stage, and the temperature is recorded every △t1 minute; Products that have passed the inspection are put into storage in the order of inspection time, and the first-in-first-out principle is adopted. The purpose of this is to ensure the freshness and quality stability of the products and avoid the performance degradation caused by long-term storage of products. For example, the tires that are put into the warehouse first will be arranged for sale first to ensure that consumers can buy relatively new products; For qualified rubber products that have not been shipped out of the warehouse, set an inspection cycle. For example, according to product characteristics and storage environment, general rubber products can be inspected once every 30 days, and the inspection period can be shortened to 15 days for products that are prone to aging or high-precision products; Using machine vision inspection software, through image preprocessing, feature extraction and pattern recognition algorithms, the appearance of rubber products is automatically inspected, including whether there are abnormal changes such as discoloration, deformation, cracking, etc. If the appearance of the product changes, the key production information of the abnormal product is read through a fixed RFID scanner, including the storage time, the time of the three vulcanization stages and the temperature change data. The system calculates the duration of different stages [ai, bi] based on the sequence of the time used in the three vulcanization stages of these products. For example, the time series of the heating stage of 10 products with appearance changes is [30, 32, 28, 31, 33, 29, 30, 34, 31, 27] (unit: minutes). By calculating the maximum and minimum values ​​of the sequence, the duration interval [27, 34] is determined; According to the temperature change data, the temperature mean sequence Temi, i∈[1,3] of each stage is calculated. For example, the temperatures of 10 products at the 10th second of the heating stage are 100℃, 102℃, 98℃, 101℃, 103℃, 99℃, 100℃, 104℃, 101℃, and 97℃ respectively. The temperature mean at this time point is (100+102+98+101+103+99+100+104+101+97)÷10=100.5℃. Similarly, the mean sequence Tem1 of the entire heating stage is calculated. For newly produced qualified rubber products, the system automatically compares the time tti used in the three stages of vulcanization with [ai,bi]. If tti∈[ai,bi], the product is marked as a product to be observed, and the temperature change sequence Wai of the three stages of vulcanization of the product to be observed is extracted. The similarity Si between the sequence Wai and Temi is calculated respectively, i=1 corresponds to the heating stage, i=2 corresponds to the constant temperature stage, and i=3 corresponds to the cooling stage. The similarity threshold Sth is set, and the number num that satisfies St>Sth is counted. If num>=2, it indicates that the temperature change sequence of the product is similar to that of the product with quality change in at least two stages, and it is marked as a key product. Focus on the specific area where the products are placed in the warehouse, which is equipped with more intensive environmental monitoring equipment, such as temperature and humidity sensors, light sensors, etc., and increase the inspection frequency, which is the minimum value in the saved time series.

[0023] A rubber numerically controlled electric heating cycle vulcanizer, the vulcanizer comprising: The main frame structure is composed of a four-column or frame-type bracket, including an upper mold that can move up and down and a fixed lower mold. The upper mold and the lower mold are driven to close by a hydraulic or pneumatic device. A pressure sensor and a displacement sensor are set between the upper mold and the lower mold to monitor the mold deformation and pressure distribution in real time, and are linked with the temperature range recognition and area calculation modules of the control system to realize the pressure-temperature-displacement multi-parameter coordinated control; The electric heating circulation heating system includes a resistance wire or electromagnetic induction heating element embedded in the mold, a spiral coil heat transfer medium channel surrounding the mold, and an independent temperature control module. The main heating module and the auxiliary circulation module are linked by heat transfer oil or water medium circulation to achieve rapid temperature rise and uniformity control of the mold temperature, and communicate with the temperature rise stage control module, constant temperature stage control module and temperature drop stage control module of the control system to dynamically adjust the heating power; The multi-region dynamic pressure adjustment system includes multiple hydraulic cylinders or pneumatic cylinders distributed under or on the side of the mold. Each cylinder corresponds to an independent pressure adjustment unit. The pressure adjustment unit is connected to the temperature rise stage control module, the constant temperature stage control module and the temperature drop stage control module of the control system. The local pressure is dynamically adjusted based on the pressure compensation command sent by the control system to support differentiated pressure control in different areas during the vulcanization process. The thermal imaging integrated monitoring module includes a high temperature resistant infrared transparent window installed on the side or top of the mold, an electric zoom thermal imager and a mechanical arm positioning device. The thermal imager collects temperature field data of the vulcanization process in real time through the infrared window and transmits it to the thermal imaging monitoring and area division module of the control system to realize real-time monitoring of the temperature field and area division; The intelligent control interface realizes data interaction with the control system through an industrial computer or PLC, and supports the coordinated control of the electric heat circulation heating system, the multi-zone pressure dynamic adjustment system and the thermal imaging integrated monitoring module. The intelligent control interface has a built-in edge computing module, which can analyze the vulcanization parameters in real time and trigger early warnings, and work with the product management and quality monitoring modules of the control system to realize vulcanization data storage and quality traceability.

[0024] Some of the data in the above formulas are dimensionless and numerically calculated. Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0025] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A rubber CNC electric heating cycle vulcanizer control system, characterized in that: include: Thermal imaging monitoring and area division module, which uses a thermal imager to monitor the temperature distribution inside the vulcanizer, divides the thermal imaging image into n areas according to the shape of the rubber product in the vulcanizer, the mold structure and the temperature field distribution, and transmits the thermal imaging image of the divided area to the temperature range recognition and area calculation module; The temperature interval recognition and area calculation module collects pixels from each area of ​​the thermal imaging image, determines the temperature interval in each area according to the color or gray value of the pixel corresponding to different temperatures, calculates the area of ​​different temperature intervals, and transmits the calculated temperature interval and area corresponding to each area of ​​the thermal imaging image to the temperature rise stage control module; The control module in the heating stage determines the key temperature range according to the characteristics of the rubber material, and adjusts the applied pressure of the area according to the alternative temperature range, general temperature range, number of alternative key temperature ranges and total area of ​​different areas; The constant temperature stage control module calculates the stability of the key temperature interval of the area within the key temperature interval, adjusts the applied pressure of the area within the key temperature interval according to the stability and the average temperature in the adjacent time period, and for the area within the non-critical temperature interval, calculates its distance from the surrounding areas within the key temperature interval, finds the pressure change of the area within the key temperature interval with the smallest distance to adjust the applied pressure; The control module in the cooling stage adjusts the applied pressure according to the cooling rates of the areas within the critical temperature range and the areas within the non-critical temperature range.

2. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: The temperature reduction stage control module is followed by a product management and quality monitoring module. After the rubber product passes the preliminary inspection, the product management and quality monitoring module attaches an RFID tag to each rubber product, and uses the first-in-first-out storage principle to put the rubber product into storage. For rubber products that have not been shipped out, an inspection cycle is set, and the appearance of the rubber product is automatically inspected using machine vision inspection software. If the appearance of the product changes, the key production information of the abnormal rubber product is read by a fixed RFID scanner, and the duration interval [ai, bi] and the temperature mean sequence Temi of different stages are calculated. For newly produced qualified rubber products, the system automatically compares the time tti used in the three vulcanization stages with [ai, bi]. If tti∈[ai, bi], the product is marked as a product to be observed, and the temperature change sequence Wai of the three vulcanization stages of the product to be observed is extracted. The similarity Si between the sequence Wai and Temi is calculated respectively, and a similarity threshold Sth is set. The number num that satisfies St>Sth is counted, and if num>=2, it is marked as a key product.

3. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: The area corresponding to each temperature interval is calculated according to the formula Sij=Nij / k, where Nij is the number of pixels in each temperature interval and k is the pixel-area conversion coefficient of the thermal imager.

4. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: Calculate the distance dij = |Tij_min - Keymax| between each temperature range in region i and the key temperature range. If dij ∈ [dmin, dmax], it is marked as an alternative temperature range. If dij > dmax, it is marked as a general temperature range. If |Tij_max - Keymax| <= dij < dmin, it is marked as an alternative key temperature range. If dij < |Tij_max - Keymax|, it is marked as a key temperature range. Here, Keymax is the upper limit of the key temperature range of the rubber material, dmin and dmax are distance thresholds, and Tij_min and Tij_max are the lower and upper limits of the j-th temperature range in region i.

5. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: The specific steps for pressure adjustment for different regions i during the heating stage are as follows: Count the number of alternative temperature ranges, general temperature ranges, and alternative key temperature ranges in different regions i as num1, num2, and num3 respectively, and the total areas are Sai, Sbi, and Sci; If num2 ≠ 0 and num1 = 0, num3 = 0 in region i, then construct a pressure adjustment formula based on the average distance between the general temperature range and the key temperature range. The specific formula is as follows: Pi = P0 + k1 * avg(di) + k2 * avg(di)^2; If num1 ≠ 0 and num2 ≠ 0, num3 = 0, then construct a pressure adjustment formula based on the ratio of the total areas of the alternative temperature range and the general temperature range. The specific formula is as follows: Pi = P0 * (1 + k3 * (Sai / Sbi) + k4 * sqrt(Sai / Sbi)); If num3 ≠ 0, when Sci / Stotali >= 0.5, apply a pressure of Sbest. When Sci / Stotali < 0.5, construct a pressure adjustment formula based on the total area of the alternative key temperature range. The specific formula is as follows: Pi = Sbest * (1 - k5 * (0.5 - Sci / Stotali)); Here, P0 is the currently applied pressure, di is the distance between the general temperature range and the key temperature range, avg() is the averaging function, sqrt() is the square root function, Sbest is the best applied pressure when the rubber is in the key temperature range, and k1, k2, k3, k4, k5 are pressure adjustment coefficients.

6. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: During the constant temperature stage, if (area of the key temperature range in region i / total area of region i) > β, then this region is called a region within the key temperature range. Otherwise, it is called a region outside the key temperature range. Here, β is the area threshold.

7. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: The specific steps for pressure adjustment for different regions i during the constant temperature stage are as follows: Calculate the temperature stability index of the critical temperature interval for the area within the critical temperature interval , if σ>σmax and , appropriately reduce the regional pressure. The specific pressure adjustment formula is as follows: Pnew=Pcurrent*(1-h1*(σ-σmax)*( )); If σ>σmax and , the regional pressure needs to be appropriately increased. The specific pressure adjustment formula is as follows: Pnew=Pcurrent*(1+h2*(σ-σmax)*( )); For a region outside the key temperature range, calculate the distance dnear to the nearest region within the key temperature range around it. If dnear <= dth, then adjust its own pressure according to the pressure change of the region within the key temperature range. The specific pressure adjustment formula is: Pnew = Pcurrent + h3 * △Pkey * (Scurrent / Stotal). Otherwise, keep the current pressure unchanged; Among them, △Pkey is the pressure adjustment amount of the area in the key temperature range, Scurrent is the area of ​​the current non-key temperature range, Stotal is the total area, and Pcurrent is the current regional pressure. , is the average temperature between time t and t+△t, and h1, h2, and h3 are pressure adjustment coefficients.

8. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 1, characterized in that: The specific steps for pressure adjustment in different regions i during the cooling stage are as follows: Calculate the cooling rate of each region: vT = (Tt + △t - Tt) / △t; For the regions within the critical temperature range, if vT < vTmax, the pressure needs to be increased. The specific pressure adjustment formula is: Pnew = Pcurrent * (1 + h4 * (vTmax - vT)); If vT ∈ [vTmax, 0], the pressure should be appropriately reduced. The specific pressure adjustment formula is: Pnew = Pcurrent * (1 - h5 * (1 - Pp / Pr)); For the regions outside the critical temperature range, the specific pressure adjustment formula is: Pnew = Pcurrent * (1 + h6 * (vT - vTth) / vTth); Where vTmax is a negative number, Pp is the proportion of pixels with obvious temperature changes actually occurring within the critical temperature range, Pr is the reference value of the proportion of pixels with obvious temperature changes corresponding to occur within the critical temperature range in the ideal vulcanization state, vTth is the preset target cooling rate of the regions outside the critical temperature range, and h4, h5, and h6 are pressure adjustment coefficients.

9. A rubber CNC electric heating cycle vulcanizing machine control system according to claim 2, characterized in that: Focus on the specific area where the product is placed in the warehouse. This area is equipped with more intensive environmental monitoring equipment, and at the same time, increase the inspection frequency, which is the minimum value in the preservation time series.

10. A rubber numerical control electric heating cycle vulcanizer, used to execute a rubber numerical control electric heating cycle vulcanizer control system according to any one of claims 1 to 9, characterized in that: This vulcanizer includes: The main frame structure, which is composed of a four-column type or frame type bracket, includes an upper mold that can move up and down and a fixed lower mold. The upper mold and the lower mold are driven to close by a hydraulic or pneumatic device. A pressure sensor and a displacement sensor are arranged between the upper mold and the lower mold to monitor the die deformation and pressure distribution in real time, and are linked with the temperature range identification and area calculation module of the control system to realize multi-parameter collaborative control of pressure-temperature-displacement; The electric heating circulation heating system, including resistance wires or electromagnetic induction heating elements embedded in the mold, spiral coil type heat transfer medium channels surrounding the mold, and an independent temperature control module. The main heating module and the auxiliary circulation module are linked through heat transfer oil or water medium circulation to realize rapid temperature rise and uniformity control of the mold temperature, and communicate with the heating-up stage regulation module, constant temperature stage regulation module, and cooling stage regulation module of the control system to dynamically adjust the heating power; The multi-region pressure dynamic adjustment system, including multiple hydraulic cylinders or pneumatic cylinders distributed below or on the side of the mold. Each cylinder corresponds to an independent pressure adjustment unit. The pressure adjustment unit is communicatively connected to the heating-up stage regulation module, constant temperature stage regulation module, and cooling stage regulation module of the control system, and dynamically adjusts the local pressure based on the pressure compensation instruction sent by the control system to support differential pressure control in different regions during the vulcanization process; The thermal imaging integrated monitoring module, including a high-temperature resistant infrared transparent window installed on the side or top of the mold, an electric zoom thermal imager, and a robotic arm positioning device. The thermal imager collects the temperature field data during the vulcanization process through the infrared window in real time and transmits it to the thermal imaging monitoring and region division module of the control system to realize real-time monitoring and region division of the temperature field; The intelligent control interface realizes data interaction with the control system through an industrial computer or PLC, and supports the coordinated control of the electric heat circulation heating system, the multi-zone pressure dynamic adjustment system and the thermal imaging integrated monitoring module. The intelligent control interface has a built-in edge computing module, which can analyze the vulcanization parameters in real time and trigger early warnings, and work with the product management and quality monitoring modules of the control system to realize vulcanization data storage and quality traceability.

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