A method for monitoring the material cutting of rubber compound for tread production

Abstract

The present invention provides a method for monitoring the stock cutting of rubber compound for tread production. A pair of gratings for detecting the rubber compound are installed at the entrance of the conveyor belt at the feeding port of the main rubber mixer, and a proximity switch is installed on the free roller at the end of the conveyor belt to detect the rotation of the roller. Then, a real-time current comparison program for the motor is written in the main machine program. During the production process of the extruder, when the grating at the entrance of the conveyor belt does not detect the rubber compound or the proximity switch at the end of the conveyor belt does not detect the rotation of the free roller, there will be a feeding conveyor belt stock cutting alarm reminder on the computer of the main machine console, and there will be an audible and visual alarm on the console, which can timely prompt the employee of the feeding operation status. For the tread produced by using this method, the annual rework rate caused by stock cutting of the rubber compound is as low as 0.12%.

Description

Technical Field

[0001] The present invention relates to the technical field of tire production and manufacturing, and particularly relates to a method for monitoring the material breakage of the rubber compound for tread production. Background Art

[0002] The tread is the main working part of the tire. The tread directly contacts the road surface, protects the carcass ply and the buffer layer from punctures and direct impacts, improves the adhesion between the tire and the road surface, and transmits traction force, steering force, and braking force through the tread pattern. Since the entire tread is located on the outermost side of the tire, it is the place where the tire is subjected to the most complex and severe stresses. High requirements are imposed on its quality and performance, and it is required to achieve low rolling friction, high anti-slip, and wear resistance, which are closely related to the fuel consumption, safety, and lifespan of the vehicle.

[0003] In the process of rubber product processing, the extrusion forming method is widely used because of its simple operation method, high production efficiency, and good product quality. Connect the head with the extruder, supply the refined rubber compound for each part of the tread by the extruder, and then extrude it through the die for shaping. Each process in the extrusion process and the manufacturing production line has an important impact on the product quality. It is necessary to carry out strict management to ensure that the weights and cross-sectional profile dimensions of various semi-finished products meet the process requirements, and the tolerances of grams, length, width, and thickness are within the process requirement benchmarks. If the manufactured parts do not meet the design requirements, it will lead to uneven geometric shape and mass distribution of the rubber tire, and the uneven tread will cause the vibration of the whole vehicle, which will have an adverse impact on the serviceability of the vehicle during high-speed operation.

[0004] However, in the process of tread production, it is often difficult to control the key parameters that affect the tread quality. For a long time, the feeding of the upper computer for the tread has been frequently interrupted, and the employees cannot find it in time, resulting in unqualified product dimensions and an increase in the rework of the shaped rubber.

[0005] To solve the above problems, the research team installed a detection and alarm device on the conveyor belt of the upper computer to timely prompt the employees of the feeding operation status. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for monitoring the material breakage of the rubber compound for tread production, so as to solve the problems of frequent interruption of the feeding of the upper computer for the tread, the employees cannot find it in time, resulting in unqualified product dimensions and an increase in the rework of the shaped rubber.

[0007] The technical solution of the present invention is as follows:

[0008] The purpose of the present invention is to provide a method for monitoring the material breakage of the rubber compound for tread production, including the following steps:

[0009] S1 Install a detection device;

[0010] S2 Write a judgment program;

[0011] S3 Alarm according to the detection signal and the judgment program.

[0012] Furthermore, in step S1, install a detection device, specifically, install a detection device on the conveyor belt for the upper computer to transmit, including a grating and a proximity switch.

[0013] Furthermore, the grating includes a pair of light emitters and light receivers, and is installed at the entrance of the feeding conveyor belt of the rubber molding main machine for detecting rubber material; when feeding, the rubber material passes through the middle of the grating. When there is rubber material between the light emitter and the light receiver, there is no voltage output on the black output line at the light receiver end. When there is no rubber material between the light emitter and the light receiver, the black output line at the light receiver end outputs DC24V voltage, and this signal is collected through the remote I / O module.

[0014] Furthermore, the proximity switch is installed on the free roller at the end of the conveyor belt for detecting the rotation of the roller. When the free roller rotates normally, the sensor will continuously input 24V to the PLC at intervals.

[0015] Furthermore, the grating and the proximity switch are connected to the I / O module through signal lines, and the I / O module is connected to the computer of the extruder main machine through a network cable.

[0016] Furthermore, in step S2, write a judgment program, specifically, write a real-time current comparison program for the motor in the main machine program. During the normal production process of the extrusion main machine, when the current of the motor is lower than the average value of the current in the previous minute for 2 consecutive seconds, the program judges that the extruder is out of material.

[0017] Furthermore, the grating signal judgment program at the entrance of the feeding conveyor belt of the rubber molding main machine is specifically as follows: when the grating at the entrance of the conveyor belt does not detect rubber material, output a 24V signal, and it is concluded that there is a material shortage here.

[0018] Furthermore, the proximity switch signal judgment program for the free roller is specifically as follows: if there is no 24V signal or a 24V signal is always input to the PLC, it means that the free roller does not rotate, and it is concluded that there is a material shortage here.

[0019] Furthermore, after the program judges that there is a material shortage, send an alarm reminder for the feeding conveyor belt to the computer of the main operation console, and at the same time, the operation console gives an audible and visual alarm. When the current resumes, the alarm stops automatically.

[0020] Furthermore, in step S3, alarm according to the detection signal and the judgment program, specifically, the signal output by the detection device is judged by the judgment program, and the audible and visual alarm on the operation console has 2 response states:

[0021] When the audible and visual alarm light is not on, that is, when there is no alarm, it means that the feeding is normal;

[0022] When the audible and visual alarm light flashes, it indicates a material shortage, and the employee needs to check the rubber material at both ends of the feeding conveyor belt.

[0023] The beneficial effects of the present invention are as follows:

[0024] 1. By adding a detection and alarm device to the upper computer conveyor belt, it timely prompts the employee of the feeding operation status, ensures the qualified product size, and reduces the rework caused by material shortage.

[0025] 2. The method for reducing the tread rework rate is practical. After implementation on the production line, the annual tread rework rate caused by rubber material shortage has decreased from 0.31% to 0.12%, saving 21,977.04 yuan in cost per year. Description of the Drawings

[0026] Figure 1 It is a schematic diagram of the steps for reducing the tread rework rate in Embodiment 1;

[0027] Figure 2 It is a schematic diagram of the grating principle in Embodiment 1;

[0028] Figure 3 It is a schematic diagram of the proximity switch principle in Embodiment 1. 1 is the positive power supply wire, 3 is the negative power supply wire, and 4 is the output wire;

[0029] Figure 4 It is a schematic diagram of the connection between the grating and the proximity switch in Embodiment 1;

[0030] Figure 5 It is a schematic diagram of the material shortage alarm program in Embodiment 1;

[0031] Figure 6 It is a line chart of the rework rate caused by feeding shortage in 2022 and 2023. Detailed Implementation Manner

[0032] Embodiment 1

[0033] Figure 1 It is a schematic diagram of the steps for reducing the tread rework rate in this embodiment. As can be seen from the figure, it includes the following steps:

[0034] S1 Install the detection device: Install the detection device on the upper computer conveyor belt, including a grating and a proximity switch.

[0035] Figure 2This is the schematic diagram of the grating in this embodiment. The grating model used in this embodiment is Panasonic Electric Works NA2-N12-PN. It includes a pair of light projectors and light receivers, which are installed at the entrance of the feeding conveyor belt of the rubber molding machine host to detect the rubber compound. When feeding, the rubber compound passes through the middle of the grating. When there is rubber compound between the light projector and the light receiver, there is no voltage output on the black output wire at the light receiver end. When there is no rubber compound between the light projector and the light receiver, the black output wire at the light receiver end outputs DC24V voltage, and this signal is collected through the remote IO module.

[0036] Figure 3 This is the schematic diagram of the proximity switch in this embodiment. The proximity switch model used in this embodiment is Balluff Automation BESM12MI-POC40B-BP03. It is installed on the free roller at the end of the conveyor belt to detect the rotation of the roller. When the free roller rotates normally, the sensor will continuously input 24V to the PLC at intervals.

[0037] Figure 4 This is the connection schematic diagram of the grating and the proximity switch in this embodiment. The grating and the proximity switch are connected to the I / O module through signal lines, and the I / O module is connected to the computer of the extruder host through a network cable.

[0038] S2 Write a judgment program. Specifically, write a program to compare the real-time current of the motor in the host program. During the normal production process of the extrusion host, when the current of the motor is lower than the average value of the current in the previous minute for 2 consecutive seconds, the program judges that the extruder is out of material. Figure 6 This is the schematic diagram of the out-of-material alarm program in this embodiment.

[0039] The program for judging the grating signal at the entrance of the feeding conveyor belt of the rubber molding machine host is specifically as follows: when the grating at the entrance of the conveyor belt does not detect the rubber compound, a 24V signal is output, indicating that there is a material shortage here.

[0040] The program for judging the proximity switch signal of the free roller is specifically as follows: if there is no 24V signal or a 24V signal is continuously input to the PLC, it means that the free roller is not rotating, indicating that there is a material shortage here.

[0041] After the program judges that there is a material shortage, an alarm reminder for the feeding conveyor belt is sent to the computer of the host operation console, and at the same time, an audible and visual alarm is issued at the operation console. When the current resumes, the alarm stops automatically.

[0042] S3 Alarm according to the detection signal and the judgment program. Specifically, the signal output by the detection device is judged by the judgment program, and there are 2 response states for the audible and visual alarm at the operation console:

[0043] When the audible and visual alarm light is not on, that is, when there is no alarm, it means that the feeding is normal;

[0044] When the audible and visual alarm light is flashing, it means that there is a material shortage, and the operator needs to check the rubber compound at both ends of the feeding conveyor belt.

[0045] The actual effect of the judgment program in this embodiment is that when the grating at the entrance of the conveyor belt does not detect the rubber compound, or the proximity switch at the end of the conveyor belt does not detect the rotation of the free roller within 30 seconds, there will be a feeding conveyor belt stock outage alarm reminder on the computer of the main machine console, and there will be an audible and visual alarm on the console at the same time.

[0046] By the above method, at the start of production, the detection device of the present invention is started. Through the pre-written judgment program, when the grating at the entrance of the conveyor belt does not detect the rubber compound, or the proximity switch at the end of the conveyor belt does not detect the rotation of the free roller within 30 seconds, there will be a feeding conveyor belt stock outage alarm reminder on the computer of the main machine console, and there will be an audible and visual alarm on the console at the same time, which can prompt the employees of the feeding operation status in real time, deal with the stock outage situation, and reduce the reprocessing of the shaped rubber due to the stock outage.

[0047] In order to verify the effectiveness of the present invention, the R & D team conducted a series of verification tests, and the excerpts are as follows.

[0048] Table 1 shows the stock outage and reprocessing rate of feeding without using the present invention from January to December 2022. The annual reprocessing rate caused by the stock outage of feeding is 0.31%.

[0049] Table 1 Stock Outage and Reprocessing Rate of Feeding from January to December 2022

[0050] Date Glue consumption / kg Remelting weight / kg Remelting rate % January 2022 2886696 7664.9 0.27％ February 2022 2762767 10464.7 0.38％ March 2022 4214588 9620.3 0.23％ April 2022 2706003 8083.8 0.30％ May 2022 3188674 10909.9 0.34％ June 2022 3668810 9157.9 0.25％ July 2022 3850565 10544.0 0.27％ August 2022 3208832 10139.1 0.32％ September 2022 2804907 9628.6 0.34％ October 2022 3317462 9651.3 0.29％ November 2022 3196053 12870.2 0.40％ December 2022 2750921 9282.1 0.34％ Total 38556277 118016.9 0.31％

[0051] Among them, the reprocessing rate is calculated by the following formula:

[0052]

[0053] Table 2 shows the stock outage and reprocessing rate of feeding from January to December 2023 after adopting the method of the present invention. The annual reprocessing rate caused by the stock outage of feeding is 0.12%.

[0054] Table 2 Stock Outage and Reprocessing Rate of Feeding from January to November 2023

[0055] Date Glue consumption kg Remelting weight kg Remelting rate % January 2023 2282771 4101.4 0.18％ February 2023 3429816 5844.8 0.17％ March 2023 4334253 3691.7 0.09％ April 2023 4256639 4866.1 0.11％ May 2023 3852384 4779.9 0.12％ June 2023 3642581 4324.4 0.12％ July 2023 4021462 4572.0 0.11％ August 2023 4218122 5573.8 0.13％ September 2023 4008279 4717.2 0.12％ October 2023 5779244 3944.3 0.07％ November 2023 4497614 4838.7 0.11％ December 2023 4122557 4947.1 0.12％ Total 44323165 51254.3 0.12％

[0056] Figure 6 It is a line chart of the reprocessing rate caused by the stock outage of feeding in 2022 and 2023. By comparison, it can be seen that after the implementation of the production line, the annual reprocessing rate of the tread caused by the stock outage of the rubber compound has decreased from 0.31% to 0.12%.

[0057] Calculated according to the rubber consumption of the tread of 38,556,277 kg from January to December 2022, the reduction of the reprocessing of the shaped rubber is 38,556,277 * 0.19% = 73,256.9 kg. Calculated at an average processing cost of 0.30 yuan / kg:

[0058] Monthly cost savings from reprocessing = 73256.9 * 0.3 / 12 = 1831.42 yuan.

[0059] Annual cost savings = 1831.42 * 12 = 21977.04 yuan.

[0060] Although the present invention has been described in detail above with general descriptions, specific embodiments and experiments, some modifications or improvements can be made thereto based on the present invention, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of the present invention claimed.

Claims

1. A method for monitoring the stock cutting of rubber compound for tread production, characterized in that, It includes the following steps: S1 Install the detection device. Install the detection device on the conveyor belt transported by the host computer, including a grating and a proximity switch; The grating includes a pair of light emitters and light receivers, and is installed at the entrance of the feeding conveyor belt of the rubber-forming host to detect the rubber compound. When feeding, the rubber compound passes through the middle of the grating. When there is a rubber compound between the light emitter and the light receiver, there is no voltage output on the black output line at the light receiver end. When there is no rubber compound between the light emitter and the light receiver, the black output line at the light receiver end outputs DC24V voltage, and this signal is collected through the remote I / O module; The proximity switch is installed on the free roller at the end of the conveyor belt to detect the rotation of the roller. When the free roller rotates normally, the sensor continuously inputs 24V to the PLC at intervals; The grating and the proximity switch are connected to the I / O module through signal lines, and the I / O module is connected to the computer of the extruder host through a network cable; S2 Write a judgment program. Write a program for comparing the real-time current of the motor in the host program. During the normal production process of the extrusion host, when the current of the motor is lower than the average value of the current in the previous minute for 2 consecutive seconds, the program judges that the extruder is out of material; The specific program for judging the grating signal at the entrance of the feeding conveyor belt of the rubber-forming host is that when the grating at the entrance of the conveyor belt does not detect the rubber compound, a 24V signal is output, indicating that there is a material shortage here; The specific program for judging the proximity switch signal of the free roller is that if there is no 24V signal or a 24V signal is continuously input to the PLC, it means that the free roller is not rotating, indicating that there is a material shortage here; S3 Alarm according to the detection signal and the judgment program. After the program judges that there is a material shortage, it sends an alarm reminder for the feeding conveyor belt to the computer of the host operation console, and at the same time, an audible and visual alarm is issued at the operation console. When the current resumes, the alarm stops automatically; After the signal output by the detection device is judged by the judgment program, the audible and visual alarm at the operation console has two response states: When the audible and visual alarm light is not on, that is, when there is no alarm, it means that the feeding is normal; When the audible and visual alarm light is flashing, it means that there is a material shortage, and the employee needs to check the rubber compound situation at both ends of the feeding conveyor belt.

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