A membrane-free monitoring method for air cushion machine and an air cushion machine

Abstract

The present invention relates to a non-film monitoring method for an air cushion machine and an air cushion machine, the method comprising: real-time acquisition of the temperature of a heating module in the air cushion machine, and judging whether the air cushion machine is running with a film according to the temperature change of the heating module during the start-up process of the air cushion machine and during the operation with a film. The present invention can replace the original non-film detection module in the air cushion machine, realize the non-film detection function without the need for an actual detection module, and can effectively solve the maintenance cost of the traditional non-film detection module and the actual module cost problem.

Description

Technical Field

[0001] The present invention relates to the field of intelligent manufacturing technology, and in particular to a membrane-free monitoring method for an air cushion machine and an air cushion machine. Background Art

[0002] One of the important functions of the buffer air cushion machine is to perform real-time film-free detection during operation. This function can realize intelligent control such as shutdown when there is no film, shutdown when the film penetration is abnormal, and prompt the customer for irregular film operation when starting. After one-button start, there is no need for real-time supervision by personnel, and the equipment can be shut down by intelligent control, which is safe and efficient.

[0003] The traditional non-membrane detection functional module solution is a mechanical structure + electronic detection method. During operation, the membrane is driven by a mechanical wheel, and the electronic detection module detects the rotation state of the mechanical wheel in real time, thereby converting the film movement of the equipment into an electrical signal. The system determines the operation status of the membrane in the equipment through the changes in the electrical signal.

[0004] The accuracy of the control of the above-mentioned traditional membrane-free detection scheme is limited by the coordination between the membrane and the mechanical structure, the stability of the mechanical structure, the matching of the mechanical and electronic detection devices, and the stability and life of the electronic detection devices. Therefore, in the actual large-scale use process, mechanical failure, electronic failure, or transmission matching abnormalities often occur, resulting in abnormalities and misjudgments of the membrane-free detection function, resulting in increased after-sales maintenance costs.

[0005] In addition, in addition to the hidden maintenance costs, the membrane-free detection module also includes mechanical material costs, processing costs, and electronic component costs. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes a membrane-free monitoring method for an air cushion machine and an air cushion machine.

[0007] The specific plan is as follows:

[0008] A method for monitoring an air cushion machine without a film comprises: collecting the temperature of a heating module in the air cushion machine in real time, and judging whether the air cushion machine is running with a film according to the temperature change of the heating module during the start-up process of the air cushion machine and the operation process with a film.

[0009] Furthermore, when the air cushion machine is in the startup process, it is determined whether there is a situation in which the temperature of the heating module first drops from the target temperature to a temperature exceeding the first temperature change threshold within the first rated time and then recovers to the target temperature. If so, it is determined that the air cushion machine is in a membrane-carrying operation state; if not, it is determined that the air cushion machine is in a membrane-free operation state.

[0010] Furthermore, when the air cushion machine is in the process of operating with a film, it is determined whether the temperature of the heating module rises to a temperature exceeding the second temperature change threshold within the second rated time and then returns to the target temperature. If so, it is determined that the air cushion machine is in a demolding or film-free operating state; if not, it is determined that the air cushion machine is in a film-operating state.

[0011] Furthermore, the operating process after the temperature of the heating module gradually rises from the initial temperature to the target temperature is regarded as the startup process of the air cushion machine. When the air cushion machine is determined to be in a film-carrying operation state during the startup process of the air cushion machine, the process after this moment is regarded as the film-carrying operation process of the air cushion machine.

[0012] Further, the target temperature is at least 100 degrees Celsius, the first temperature change threshold is 5-15 degrees Celsius, and the second temperature change threshold is 5-15 degrees Celsius.

[0013] Furthermore, the temperature of the heating module is collected at time intervals of unit time, the first rated time is 2-5 unit time, the second rated time is 1-2 unit time, and the unit time is 3-10 seconds.

[0014] Furthermore, when it is detected that the air cushion machine is in a demoulding or film-free operation state during the film-carrying operation, the air cushion machine is controlled to stop running and an alarm is sounded.

[0015] Furthermore, a constant temperature sealing mechanism is arranged inside the air cushion machine, and the constant temperature control mechanism is composed of a heating wire, a heating wire surface temperature detection device and a belt transmission structure.

[0016] An air cushion machine comprises: a heating module, a temperature sensor and a controller; the temperature sensor is used to collect the temperature of the heating module and send it to the controller; the controller determines whether the air cushion machine is running with a film by the method described in the embodiment of the present invention.

[0017] Furthermore, it also includes a PID temperature control module, which is used to control the temperature of the heating module to preheat the heating module during the startup process so that its temperature rises to the target temperature, and then performs constant temperature adjustment according to the collected temperature of the heating module. When the temperature of the heating module drops from the target temperature, the power of the heating module is increased to make the temperature of the heating module constant at the target temperature again; when the temperature of the heating module rises from the target temperature, the power of the heating module is reduced.

[0018] The present invention adopts the above technical solution to replace the original membrane-free detection module in the air cushion machine, realize the membrane-free detection function without the need for an actual detection module, and effectively solve the maintenance cost of the traditional membrane-free detection module and the actual module cost problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1Shown is a schematic diagram of a temperature variation curve of a heating module in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] To further illustrate various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in this field should be able to understand other possible implementations and advantages of the present invention.

[0021] The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

[0022] In this embodiment, a constant temperature sealing mechanism is arranged inside the air cushion machine, and the constant temperature control mechanism is composed of a heating wire, a heating wire surface temperature detection device and a belt transmission structure.

[0023] The operation process of the air cushion machine includes a startup process and a film-carrying operation process. The operation process after the temperature of the heating module gradually rises from the initial temperature to the target temperature is regarded as the startup process of the air cushion machine. When the air cushion machine is determined to be in a film-carrying operation state during the startup process of the air cushion machine, the process after this moment is regarded as the film-carrying operation process of the air cushion machine.

[0024] The present embodiment provides a method for monitoring an air cushion machine without a film, comprising: collecting the temperature of a heating module in the air cushion machine in real time, and judging whether the air cushion machine is running with a film based on the temperature change of the heating module during the startup of the air cushion machine and during the operation with a film.

[0025] 1. Determine whether the air cushion machine is running with film during startup.

[0026] (1) Temperature control during the preheating process (i.e., the process in which the temperature of the heating module gradually rises from the initial temperature to the target temperature):

[0027] During the heating process, the heating module will continuously dissipate heat to the outside world, and the heat dissipation can be defined as Q 散热 According to the law of conservation of energy, the energy conservation formula during the preheating process is:

[0028] Q 总 =Q 积累 +Q 散热

[0029] Among them, Q 总 represents the total heat emitted by the heating module (electric heating wire is used in this embodiment), Q 积累 It represents the energy absorbed by the heating module from the initial temperature T1 to the target temperature T2.

[0030] There are also:

[0031] Q总 =Pt

[0032] Q 积累 =cmt=cm(T2-T1)

[0033] Therefore, we can get:

[0034] Pt=cm(T2-T1)+Q 散热

[0035] Among them, c represents the specific heat capacity of the heating module material; m represents the mass of the heating module, both of which can be regarded as constants; P represents the system power; t represents the preheating time, t=T2-T1.

[0036] (2) Temperature control after entering the constant temperature control stage after preheating:

[0037] In the constant temperature control stage and when the air cushion machine is running without film, the system will control the temperature of the heating module to maintain the set temperature value (i.e., target temperature T2), so it can be regarded that the heating module no longer absorbs heat, but maintains the set target temperature T2 under the control of the system PID, and the accumulated heat is very small, which can be regarded as 0 (i.e., Q 积累 ≈0), at this time, the heat generated by the heating module is approximately equal to the heat dissipated by the heating module, that is,

[0038] Pt≈Q 散热

[0039] In the constant temperature control stage, the equipment starts to run with the film, and the heating module will heat-seal the film. At this time, the film will take away a lot of heat. At this time, the original accumulated heat of the heating module will be taken away by the film, and the temperature of the heating module will drop for a short time. When the system PID control detects the temperature drop, it will increase the power output to compensate for the heat taken away by the film, and finally make the temperature of the heating module constant again at the target temperature T2. After the constant temperature, the accumulated heat of the heating module is reduced to a very small value, which can be regarded as 0 (that is, Q 积累 ≈0), according to the law of conservation of energy:

[0040] (P+ΔP)t≈Q 散热 +Q 膜

[0041] Here, ΔP represents the power increase.

[0042] Combining the above energy conservation formula, it can be concluded that the heat taken away by the membrane from the start-up to the constant temperature and then to the start of membrane operation and constant temperature is approximately equal to the heat added after the system increases its function, that is, ΔPt≈Q 膜 The system determines this process as a normal membrane startup process.

[0043] If the equipment starts to coat the film from the constant temperature stage, and the system does not detect that the temperature of the heating module drops briefly and then stabilizes at the target temperature T2 within the specified time, but remains in the constant temperature control stage of the set target temperature T2, and the power of the heating module does not increase, the system will determine that it is operating without a film, force a shutdown and issue an alarm.

[0044] 2. Determine whether the air cushion machine is running with film during the film operation.

[0045] During the membrane operation, (P+ΔP)t≈Q 散热 +Q 膜 If there is no film or the film penetration is abnormal, the film will be separated from the heating transmission module. At this time, the film will take away the heat of the heating block, that is, Q 膜 =0, since (P+ΔP)t>Q 散热 , the temperature of the heating module will rise for a short time. When the system PID control detects a rapid temperature rise, it will be judged as no-film operation, and the machine will be forced to shut down and alarm. When the system does not detect the abnormal short-term rise in the temperature of the heating module, the equipment will run normally until it is manually shut down or shut down by no-film control.

[0046] Based on the above principle, in this embodiment, when the air cushion machine is in the startup process, it is determined whether the temperature of the heating module first drops from the target temperature to a temperature exceeding the first temperature change threshold within the first rated time and then recovers to the target temperature. If so, it is determined that the air cushion machine is in the film-carrying operation state; if not, it is determined that the air cushion machine is in the film-free operation state. When the air cushion machine is in the film-carrying operation process, it is determined whether the temperature of the heating module rises to a temperature exceeding the second temperature change threshold within the second rated time and then recovers to the target temperature. If so, it is determined that the air cushion machine is in the demoulding or film-free operation state; if not, it is determined that the air cushion machine is in the film-carrying operation state.

[0047] The values ​​of the first temperature change threshold, the second temperature change threshold, the first rated time, and the second rated time can be set by those skilled in the art according to test data. The following experiment is conducted in this embodiment:

[0048] Test method: Set the target temperature T2 to at least 100 degrees Celsius (normal heat sealing temperature of the film), start the air cushion machine with film, and record the temperature of the heating module every 5 seconds until the film (about 30 meters long) is used up and the air cushion machine automatically stops. The temperature record of the heating module is shown in Table 1. The temperature change curve of the heating module drawn according to Table 1 is shown in Figure 1 shown.

[0049] Table 1

[0050]

[0051] from Figure 1 It can be seen that:

[0052] (1) After startup, the temperature may be lowered for a short period of time during the process of detecting the presence of film;

[0053] (2) The temperature value detected during the film operation is consistent with the set temperature value under PID regulation;

[0054] (3) When the detected temperature value rises for a short time, the system determines that there is no film or the film is peeling off, the equipment automatically stops, and prompts the abnormality.

[0055] Based on the above experimental results, in this embodiment, the first temperature change threshold is set to 5-15 degrees Celsius, the second temperature change threshold is set to 5-15 degrees Celsius, the first rated time is set to 2-5 unit times, the second rated time is set to 1-2 unit times, and the unit time is 3-10 seconds.

[0056] This embodiment also provides an air cushion machine, including: a heating module, a temperature sensor and a controller. The temperature sensor is used to collect the temperature of the heating module and send it to the controller; the controller determines whether the air cushion machine is running with a film through the above method of this embodiment.

[0057] Furthermore, the air cushion machine in this embodiment also includes a PID temperature control module, which is used to control the temperature of the heating module to preheat the heating module during the startup process so that its temperature rises to the target temperature, and then performs constant temperature adjustment according to the collected temperature of the heating module. When the temperature of the heating module drops from the target temperature, the power of the heating module is increased to make the temperature of the heating module constant at the target temperature again; when the temperature of the heating module rises from the target temperature, the power of the heating module is reduced.

[0058] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A membrane-free monitoring method for an air cushion machine, characterized in that: include: The temperature of the heating module in the air cushion machine is collected in real time, and whether the air cushion machine is running with a film is determined according to the temperature changes of the heating module during the startup process and the operation process with a film. When the air cushion machine is in the startup process, it is determined whether there is a situation that the temperature of the heating module first drops from the target temperature to a temperature exceeding the first temperature change threshold within the first rated time and then recovers to the target temperature. If so, it is determined that the air cushion machine is in the operation state with a film; if not, it is determined that the air cushion machine is in the operation state without a film. When the air cushion machine is in the operation process with a film, it is determined whether the temperature of the heating module rises to a temperature exceeding the second temperature change threshold within the second rated time and then recovers to the target temperature. If so, it is determined that the air cushion machine is in the demolding or operation state without a film; if not, it is determined that the air cushion machine is in the operation state with a film.

2. The air cushion machine membrane-free monitoring method according to claim 1, characterized in that: The operation process after the temperature of the heating module gradually rises from the initial temperature to the target temperature is regarded as the startup process of the air cushion machine. When the air cushion machine is determined to be in the film-carrying operation state during the startup process of the air cushion machine, the process after this moment is regarded as the film-carrying operation process of the air cushion machine.

3. The air cushion machine membrane-free monitoring method according to claim 1, characterized in that: The target temperature is at least 100 degrees Celsius, the first temperature change threshold is 5-15 degrees Celsius, and the second temperature change threshold is 5-15 degrees Celsius.

4. The air cushion machine membrane-free monitoring method according to claim 1, characterized in that: The temperature of the heating module is collected at time intervals of unit time, the first rated time is 2-5 unit time, the second rated time is 1-2 unit time, and the unit time is 3-10 seconds.

5. The air cushion machine membrane-free monitoring method according to claim 1, characterized in that: When it is detected that the air cushion machine is in the demoulding or film-free operation state during the film-carrying operation, the air cushion machine is controlled to stop and an alarm is sounded.

6. The air cushion machine membrane-free monitoring method according to claim 1, characterized in that: A constant temperature sealing mechanism is arranged inside the air cushion machine, and the constant temperature control mechanism is composed of a heating wire, a heating wire surface temperature detection device and a belt transmission structure.

7. An air cushion machine, characterized in that: include: A heating module, a temperature sensor and a controller; the temperature sensor is used to collect the temperature of the heating module and send it to the controller; the controller determines whether the air cushion machine is running with a film by any method described in claims 1 to 6.

8. The air cushion machine according to claim 7, characterized in that: It also includes a PID temperature control module, which is used to control the temperature of the heating module to preheat the heating module during the startup process so that its temperature rises to the target temperature, and then performs constant temperature adjustment according to the collected temperature of the heating module. When the temperature of the heating module drops from the target temperature, the power of the heating module is increased to make the temperature of the heating module remain constant at the target temperature again; when the temperature of the heating module rises from the target temperature, the power of the heating module is reduced.

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