Vacuum wet heat sealing control method for a texture vacuum bag and vacuum heat sealing machine

Abstract

The present application relates to the field of vacuum heat sealing, in particular to a vacuum wet extraction heat sealing control method of a textured vacuum bag and a vacuum heat sealer, first, taking the rated speed of the vacuum pump motor as the benchmark N0, setting the starting speed of the vacuum pump motor as N1, the speed of N1 is lower than the speed of N0, driving the vacuum pump to extract vacuum for the textured vacuum bag at the starting speed N1; using a linear pressure sensor to replace a pressure switch to monitor the pressure change of the vacuum cavity in real time, presetting a unit time T and a corresponding preset pressure change value P, when the linear pressure sensor detects that the pressure change value in the vacuum cavity is greater than P within the time range of T, stopping vacuum extraction, and starting the heat sealing bar to heat and seal at the same time; starting vacuum extraction again in the last second of heat sealing, increasing the vacuum degree of the vacuum cavity, forcing the machine to be buckled tighter to enhance the pressure on the bag opening, seal better, and effectively improve the sealing effect of the food containing liquid.

Description

Technical Field

[0001] This invention relates to the field of vacuum heat sealing, and more particularly to a vacuum wet-extraction heat sealing control method and a vacuum heat sealing machine for textured vacuum bags.

[0002] Background technology.

[0003] Textured vacuum bags have significant applications in the food packaging industry. They seal food inside and use a vacuum sealer to remove internal gas, improving food preservation and storage. They are widely used in industrial production, commercial applications, and households. One side of a textured vacuum bag is smooth, while the other side has fine grid-like, diamond-shaped, or dot-shaped raised textures. When a vacuum is applied, these raised textures create numerous microchannels, allowing air to escape smoothly without being blocked by the pressure of the contents.

[0004] Textured vacuum bags can be used to store dry or liquid foods. Most existing vacuum sealing machines are equipped with both dry and wet suction modes. A major problem with the wet suction mode is that, because the vacuum bag contains liquid, it easily overflows during vacuuming. To address this issue, many existing vacuum sealing machines have a drain pan to collect any overflowing liquid, but this requires immediate emptying and cleaning, which is inconvenient. Furthermore, the overflowing liquid not only contaminates the vacuum chamber but also affects the sealing effect.

[0005] The industry has been dedicated to researching solutions to these problems. For example, Chinese patent application CN116101554 A proposes a control method for sealing machines used in vacuum sealing of wet bags. After vacuuming, a solenoid valve replenishes gas to the sealing chamber in reverse, causing the chamber to rise from a first negative pressure state to a second negative pressure state. This increase in pressure causes some liquid inside the sealing chamber to flow back into the bag opening, carrying any residual liquid back into the bag and removing it. This prevents the liquid from absorbing heat and affecting the sealing effect, thus improving sealing reliability. While this technique solves the problem of excessive liquid overflow, by the time the first negative pressure is reached, some liquid has already overflowed. The liquid flowing from the bag opening continuously cools the heating wire at the sealing point, affecting the sealing effect. Furthermore, reverse inflation reduces the effectiveness of the vacuuming process, failing to completely remove air and impacting preservation time and quality.

[0006] The control method proposed in Chinese patent CN113753300A can automatically and intelligently adjust the vacuuming time based on the volume of the packaged item to achieve the rated vacuum level. However, because vacuum bags containing liquid can lead to inaccurate detection results due to liquid flow, the vacuuming time is difficult to control precisely, and the problem of liquid overflow still exists. Furthermore, the method for detecting the volume of the packaged item is too complex, resulting in high equipment costs.

[0007] International patent application PCT / CN2021 / 124866 proposes a vacuum packaging method. This method obtains the total evacuation time T or the vacuum chamber's stopping pressure P by measuring the size of the packaging bag and the time difference Δt between the evacuation times of the vacuum pump group when the gas in the vacuum chamber reaches two different preset pressures. The completion of the vacuum pump group's evacuation is then confirmed by judging whether the evacuation time has reached T or the pressure in the vacuum chamber has reached P. This avoids the tedious and crude manual calculation of evacuation time, offering faster calculation speed, saving calculation time, and a simple and reliable algorithm that reduces calculation errors. This invention further combines the size of the packaging bag and the different preset pressures of the gas in the vacuum chamber to control the evacuation time and prevent over-evacuation. However, this method requires measuring both the packaging bag size and the gas in the vacuum chamber. The amount of gas in the packaging bag depends not only on the bag size but also on the shape and quantity of the food, making the control process complex and prone to errors, leading to inaccurate time control and making effective control difficult to achieve. Summary of the Invention

[0008] The purpose of this invention is to provide a vacuum wet-extraction heat-sealing control method and a vacuum heat-sealing machine for textured vacuum bags, which effectively solves the technical problem of difficulty in controlling liquid overflow in textured vacuum bags and improves the heat-sealing effect.

[0009] A method for controlling vacuum wet vacuuming and heat sealing of a textured vacuum bag includes the following steps:

[0010] After placing the textured vacuum bag containing liquid into the vacuum chamber, start the vacuum pump motor to perform vacuuming. Using the rated speed of the vacuum pump motor as the reference N0, set the starting speed of the vacuum pump motor to N1. The speed of N1 is lower than the speed of N0. Drive the vacuum pump to evacuate the textured vacuum bag at the starting speed N1. The low pumping speed makes the pressure difference between the vacuum chamber and the vacuum bag smaller, which is convenient for monitoring and control.

[0011] During the vacuuming process, a linear pressure sensor continuously detects the pressure in the vacuum chamber and monitors the pressure changes within the vacuum chamber, with a preset unit time. T and the corresponding preset pressure change value are P, when detected in The actual pressure change within the vacuum chamber within the time range T is greater than the preset pressure change value. If P is selected, the vacuuming process will stop, and the heat sealing strip will be activated for heat sealing.

[0012] The preset heat sealing time is t1. When the heat sealing time reaches the last second of the preset heat sealing time t1, the vacuum pump motor is started at the rated speed N0 to strengthen the vacuum. The preset time for strengthening the vacuum is t2. After the strengthening vacuum time ends, the vacuum heat sealing is completed.

[0013] Existing vacuum pumping devices typically detect a fixed vacuum value, which introduces significant errors and is prone to misjudgment. This often results in incomplete vacuuming before sealing, or even after vacuuming stops, excessive pressure within the vacuum chamber causing liquid to continue rising and overflowing. Current technology can only address this excessive pressure difference by backflushing to release the pressure. However, even with this method, liquid has already overflowed, continuously cooling the heating element. Insufficient sealing temperature of the heating element leads to poor sealing.

[0014] This invention utilizes the gas channels within a textured vacuum bag combined with a vacuuming speed lower than the motor's rated speed to achieve vacuuming. A linear pressure sensor, in conjunction with a controller, monitors the actual pressure change within the vacuum chamber in real time and compares it with a preset pressure change value. When the detected actual pressure change exceeds the preset value, vacuuming immediately stops, and heat sealing is initiated to prevent liquid overflow from the bag opening. During the final second of heat sealing, the motor is restarted, and a powerful vacuum is applied at the rated speed for a period of time to complete the entire vacuum heat sealing operation. This final powerful vacuuming operation effectively improves the sealing effect. Because the bag opening is already sealed, the powerful vacuuming causes the negative pressure within the vacuum chamber to rise rapidly. The strong vacuum pulls the upper and lower covers of the vacuum chamber tightly, making the sealing rings or silicone rings at the edges of the vacuum chamber press the bag more firmly, thus strengthening the seal.

[0015] This invention effectively solves the problem of liquid continuing to overflow after vacuuming is stopped. It can precisely control the timing of stopping vacuuming and heat sealing, and eliminates the need for reverse blowing. A linear pressure sensor can detect the pressure value inside the vacuum chamber in real time. Traditional vacuum sealing machines generally use pressure switches or similar pressure sensors, which can only preset a fixed pressure value and only react when that preset pressure value is reached. Even if the pressure change exceeds the preset value, it is only treated as a preset pressure change, resulting in delayed sealing and excessive liquid overflow from the bag opening, affecting the sealing effect. This application selects a linear pressure sensor that can continuously and in real time detect pressure, replacing the traditional pressure switch combined with the controller's logic control. The pressure value inside the vacuum chamber is continuously transmitted to the controller, which uses logic calculations to obtain the actual pressure change value of the vacuum chamber within a preset unit time as the key parameter for stopping vacuuming and starting heat sealing. This provides accurate and sensitive response, good sealing effect, and adaptability to bags of different sizes and textures. It eliminates the need to test each bag size and monitor the liquid inside, greatly reducing the difficulty of detection and the possibility of misjudgment.

[0016] Furthermore, the starting speed N1 is 20-30% of the motor's rated speed N0. In conventional operation, the motor starts at its rated speed immediately, which can easily lead to excessively rapid vacuuming, quickly extracting or drying out the liquid. This invention, by setting the starting speed N1 to be 20-30% lower than the motor's rated speed N0, effectively achieves vacuuming operation and prevents liquid overflow.

[0017] Furthermore, preset unit time T is 0.4-0.6s, and the preset pressure change value is... P is 4-8 kPa. A preset unit time that is too long will lead to untimely control, while one that is too short will cause misjudgments and premature sealing. Therefore, the preset unit time... The T value, set to 0.4-0.6s, provides precise feedback on the vacuuming process. The preset pressure change value effectively addresses the challenge of monitoring and assessing the varying initial pressures and volumes of different textured vacuum bags. Furthermore, the problem of a sudden pressure surge occurs when the airflow channel is blocked by liquid. By comparing the preset pressure change value with the actual change value, it's possible to accurately determine whether to stop vacuuming, without considering the size or volume of the textured vacuum bag. This simple and accurate method ensures precise judgment.

[0018] Furthermore, the preset time for enhanced vacuuming t2 is 2-3 seconds.

[0019] Furthermore, the starting speed N1 of the vacuum pump motor corresponds to the initial vacuuming speed S1, and the rated speed N0 corresponds to the speed for enhanced vacuuming S2. S2 is greater than S1. The initial vacuuming speed S1 is 1.0-2.5 L / min, which can effectively reduce the pressure difference between the vacuum chamber and the textured bag and prevent uncontrollable liquid overflow.

[0020] Furthermore, at least one side of the textured vacuum bag has a raised structure, and the two inner sides have corresponding gas channels during vacuuming. The raised structure enables the formation of several gas channels inside the vacuum bag, allowing for effective vacuuming even if the initial vacuuming pressure decreases. When the gas channels are blocked by liquid, causing the pressure to rise rapidly, the motor can be started to stop the vacuuming process, making it convenient and highly flexible to control.

[0021] Furthermore, during the initial vacuuming process, when the liquid in the textured vacuum bag is drawn in to block the gas passage, the pressure change inside the vacuum chamber increases suddenly. Upon receiving this pressure signal, the controller stops the motor and stops the vacuuming process.

[0022] Furthermore, during the initial vacuuming process, which is below the rated speed of the motor, the pumping speed is slow, the pressure difference between the inside and outside of the textured vacuum bag is relatively small, and the pressure inside the vacuum chamber is in the range of -3 to -5 kPa.

[0023] Furthermore, different models of vacuum machines have single-sealing and double-sealing options, and the sealing time varies slightly, generally ranging from 10 to 50 seconds.

[0024] Furthermore, the vacuum pump motor, linear pressure sensor, and heat sealing strip are all electrically controlled by the controller. The controller continuously reads the pressure signal detected by the linear pressure sensor and calculates the pressure within a preset unit time. The actual pressure change value within T is compared with the preset pressure change value. When the liquid in the textured vacuum bag is drawn into the gas passage and blocks it, the pressure change in the vacuum chamber increases suddenly. The controller then stops the vacuum pump motor, thereby stopping the vacuuming process and initiating the heat sealing.

[0025] Furthermore, the linear pressure sensor detects the pressure inside the vacuum chamber every 0.1 seconds and feeds it back to the controller. The preset pressure change value refers to the pressure change within a preset unit time. Within the range of T, the pressure reached in the last 0.1s is subtracted from the pressure value detected in the first 0.1s.

[0026] A vacuum heat sealing machine includes a base and a cover that can be flipped and connected. When the base and cover are closed together, they form a sealed vacuum cavity. A heat sealing strip is provided on one side of the vacuum cavity. A controller, a vacuum pump with a motor, a linear pressure sensor, and a gas pipeline are installed inside the base. The controller is electrically connected to the linear pressure sensor, the vacuum pump, and the heat sealing strip. The gas pipeline is connected to the vacuum pump and the vacuum cavity. The above control method realizes vacuum wet heat sealing of textured vacuum bags.

[0027] The above-described solution of the present invention has at least the following beneficial effects: This invention utilizes the airflow channel built into the textured bag to achieve vacuuming and gas release by controlling the vacuuming speed by reducing the rotation speed. Under normal circumstances, the airflow channel inside the textured bag can achieve vacuuming and gas release. When liquid is drawn into the airflow channel that blocks the textured bag, it will block the airflow channel, causing the pressure inside the vacuum chamber to rise rapidly in a short period of time. By monitoring the pressure change value per unit time and comparing it with the preset pressure change value, it is possible to accurately determine whether the vacuuming operation has been completed. Since the initial vacuuming speed has been reduced, the pressure difference between the inside and outside of the textured vacuum bag is small. Even if the vacuuming stops, the liquid will not continue to overflow rapidly and affect the sealing device. There is no need for reverse blowing to ensure complete vacuuming. At this time, the heat sealing effect is good, effectively solving the problem of liquid overflow in wet-vacuum textured vacuum bags. Moreover, the entire control method is simple, highly sensitive, and highly controllable.

[0028] The vacuum heat sealing machine of this invention uses a linear pressure sensor instead of a traditional pressure switch. By monitoring the pressure changes inside the vacuum chamber in real time and feeding the feedback to the controller for comparison and judgment, it can accurately vacuum and heat seal textured vacuum bags. This effectively controls the problem of excessive liquid overflow during vacuum heat sealing of textured vacuum bags containing liquid. It is suitable for various sizes of textured vacuum bags and different levels of liquid, ensuring the liquid capacity inside the textured vacuum bag, solving the problem of contamination of the vacuum machine due to liquid overflow, reducing repeated cleaning operations, and is easy to use. It has a good vacuum sealing effect and stable food preservation effect.

[0029] It should be noted that the control method of the present invention is only applicable to the wet vacuuming mode of vacuum bags with internal textures, and is not applicable to the wet vacuuming of smooth vacuum bags.

[0030] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] To more clearly illustrate the invention in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of the vacuum heat sealing machine according to an embodiment of this application. Figure 2 This is a flowchart of a vacuum wet-extraction heat-sealing control method for a textured vacuum bag according to an embodiment of this application.

[0033] Figure 3 These are images showing the sealed state of a textured vacuum bag containing liquid after it has been vacuum-sealed using an existing vacuum sealing machine.

[0034] Figure 4 These are images showing the sealed state of a textured vacuum bag containing liquid after being vacuum-sealed using the vacuum sealing machine described in this application.

[0035] Explanation of icon numbers: 1. Base; 2. Cover; 3. Vacuum chamber; 4. Heat sealing strip; 5. Air extraction port.

[0036] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0037] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "circumferential," and "radial," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0041] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0042] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings: Some embodiments of this application provide a vacuum wet-sealing control method for textured vacuum bags, such as... Figure 1 Combination Figure 2 As shown, it includes the following steps: After placing the textured vacuum bag containing liquid into the vacuum chamber 3, start the vacuum pump motor to perform vacuuming. Using the rated speed of the vacuum pump motor as the reference N0, set the starting speed of the vacuum pump motor to N1, which corresponds to the initial vacuuming speed S1. The speed of N1 is lower than the speed of N0. The vacuum pump is driven by the starting speed N1 to evacuate the textured vacuum bag.

[0043] Existing vacuum sealing machines use the rated power of the vacuum pump motor to start vacuuming. In this application's embodiment, the starting speed N1 of the vacuum pump motor is preset to be less than its rated speed N0, such as N1 being 60%, 50%, or 40% of N0. In a preferred embodiment of this application, the starting speed N1 is 20-30% of the rated speed N0 of the vacuum pump motor, for example, N1 = 20%. N0, or N1 = 25% N0, or N1 = 30% If the rated speed of the vacuum pump motor is 6,000 r / min, then the starting speed N1 of the vacuum pump motor is set to 30% of the rated speed N0, that is, the starting speed N1 of the vacuum pump motor is 1800 r / min. The vacuum operation is performed on the textured vacuum bag containing liquid using the starting speed N1. Effective vacuuming can be achieved by utilizing the airflow channels in the textured vacuum bag.

[0044] During the vacuuming process, a linear pressure sensor is used to continuously monitor the pressure change in the vacuum chamber 3, with a preset unit time. T and the corresponding preset pressure change value are P, when the linear pressure sensor is in Within the time range T, the pressure change value detected inside vacuum chamber 3 was greater than [value missing]. When P is activated, the controller issues a command to stop the vacuum pump motor and simultaneously activates the heat sealing strip 4 to heat and seal the vacuum.

[0045] Specifically, preset unit time T is defined as a unit of time, representing all the data feedback received by the controller from the linear pressure sensor within a given period. The preset unit of time is... T is 0.4-0.6s. The corresponding preset pressure change value is... P refers to the difference between two pressure values ​​within a unit of time; it is generally a positive value, with the preferred preset pressure change value being... P is 4-8 kPa, specifically 4 kPa, 5 kPa, 6 kPa, 7 kPa, or 8 kPa. The specific value can be selected based on the size of the vacuum chamber and the number of heat sealing strips of different vacuum sealing machines. The preferred preset pressure variation value is... P is selected within the range of 4-8 kPa, when If the pressure change is below 4 kPa, the pressure change is too small, which can easily lead to premature sealing due to misjudgment, resulting in the air not being completely removed from the vacuum bag; if... If P is higher than 8 kPa, control lag is likely to occur, and the seal cannot be completed in time, resulting in a large amount of liquid overflow.

[0046] Preset unit time The time T includes at least the initial time point T0 and the final time point Tz. The pressure value detected by the linear pressure sensor includes at least the initial pressure P0 and the pressure Pz corresponding to the final time point Tz, i.e., the actual pressure change value P and the preset pressure change value. P is compared. That is, the linear pressure sensor operates within a preset unit time. Within T, the detected pressure values ​​will be continuously fed back to the controller. After receiving these pressure values, the controller will respond within a preset unit time. The actual pressure change value is calculated within T. When the actual pressure change value is greater than the preset pressure change value... If P is selected, a stop vacuuming command will be issued. If the actual pressure change is not higher than the preset pressure change value, the vacuuming will stop. If P is detected, continue the vacuuming operation until the actual pressure change value is greater than the preset pressure change value. P will then control the stopping of vacuuming and timely sealing.

[0047] As one implementation method, a preset unit time is used. T is 0.5s, preset pressure change value If P is 6 kPa, the linear pressure sensor will continuously detect multiple pressure values ​​within a 0.5s time range and feed them back to the controller. The controller will subtract the pressure value at the initial time point from the pressure value at the end of the time point to obtain the actual pressure change value, and then compare it with the preset pressure change value. The pressure is compared with the preset pressure change value (P). If the actual pressure change value is not higher than the preset pressure change value of 6 kPa, the vacuuming operation continues. If the actual pressure change value exceeds 6 kPa, it indicates that the pleats of the vacuum bag are blocked by liquid, causing a sudden increase in pressure inside the vacuum chamber 3. The controller will then issue a stop vacuuming command. If only a fixed pressure value at a specific point in time is used as the judgment standard, there is a high probability of misjudgment, resulting in incomplete vacuuming or premature shut-off of vacuuming, leading to liquid overflow. This application uses a preset unit time for monitoring. Using the actual pressure change within T as the basis for judgment is more objective and accurate.

[0048] In some embodiments, a preset unit time T is 0.4-0.6s, meaning the controller calculates all data received from the linear pressure sensor within 0.4-0.6s as a time node. Preferably, it can be 0.5s, but it can also be 0.4s or 0.6s. (Preset unit time) An excessively long time interval (T) can lead to control lag and prevent accurate control. (Preset unit time) If T is too short, misjudgments may occur, and the control effect will be unstable.

[0049] In some preferred embodiments, the linear pressure sensor detects the pressure inside the vacuum chamber 3 every 0.1s and feeds it back to the controller. The pressure reached in the last 0.1s is subtracted from the pressure value detected in the first 0.1s to obtain the actual pressure change value. The calculation and comparison logic is executed by the controller.

[0050] When the controller issues a command to stop vacuuming, it simultaneously initiates the heat sealing operation, i.e., heating the heat sealing strip 4. In this embodiment, the preset heat sealing time is t1. Specifically, the time t1 can be adjusted according to the number of heat sealing strips and the power, and is not a key aspect of this invention. When the heat sealing time reaches the last second of the preset heat sealing time t1, the controller starts the vacuum pump motor at its rated speed N0 to enhance vacuuming. The preset enhanced vacuuming time is t2. After the enhanced vacuuming time ends, vacuum heat sealing is completed. The rated speed N0 corresponds to the enhanced vacuuming speed S2, where S2 is greater than S1.

[0051] In this embodiment, the vacuum pump is started at a fixed speed to extract air when the heat sealing is in the last second. At this time, the bag opening is basically heat sealed. The extraction can only cause the negative pressure in the vacuum chamber 3 to rise rapidly. The strong vacuum will suck the upper and lower cover plates of the vacuum chamber 3 tightly, which can make the silicone strip press the bag more firmly and strengthen the tightness of the seal.

[0052] As a preferred embodiment, the time for enhanced vacuuming t2 is preset to be 2-3 seconds, that is, the enhanced vacuuming time is 2-3 seconds, and the vacuum pump motor performs vacuuming operation at rated speed to enhance the heat sealing stability effect.

[0053] The initial vacuum pump motor's starting speed N1 is preset to a predetermined initial vacuum speed S (1.0-2.5 L / min). The purpose of this preset initial vacuum speed S is to effectively control the vacuuming speed, ensuring it is balanced with the gas flow within the textured vacuum bag. This effectively creates a vacuum without causing excessive pressure differentials, achieving effective control. Using this preset initial vacuum speed S as a starting point, the vacuum pump motor's starting speed N1 is also preset to achieve better control and prevent liquid overflow.

[0054] The textured vacuum bag used in this embodiment has a raised structure on at least one side of its inner surface, and the two inner sides have a number of gas channels corresponding to each other when vacuuming.

[0055] During the initial vacuuming, when the liquid in the textured vacuum bag is drawn up to block the gas passage, the pressure inside the vacuum chamber 3 will suddenly increase. This application does not use a final pressure value as the basis for control, but rather selects the actual pressure change value within a preset unit time as the comparison with the preset pressure change value. Only the final conclusion obtained causes the controller to issue a command to stop the vacuum pump motor and stop vacuuming.

[0056] In some preferred embodiments, during the initial vacuuming process, the pressure inside the vacuum chamber 3 is in the range of -3 to -5 kPa. This effectively controls liquid overflow after vacuuming stops. Insufficient pressure will result in insufficient vacuuming intensity, affecting the vacuuming time or preventing effective vacuuming altogether.

[0057] like Figure 2As shown, this embodiment proposes a vacuum heat sealing machine using the above-mentioned textured vacuum bag vacuum wet-extraction heat sealing control method, including a base 1 and a cover 2 that can be flipped and connected. When the base 1 and the cover 2 are closed together, they form a sealed vacuum cavity 3. A heat sealing strip 4 is provided on one side of the vacuum cavity 3. A controller, a vacuum pump with a motor, a linear pressure sensor, and a gas pipeline are provided inside the base 1 (the controller, the vacuum pump with a motor, the linear pressure sensor, and the gas pipeline are all provided in the vacuum heat sealing machine, not shown in the attached figure). The controller is electrically connected to the linear pressure sensor, the motor of the vacuum pump, and the heat sealing strip 4, respectively. The gas pipeline is connected to the vacuum pump and the vacuum cavity 3. The gas pipeline is provided with an air extraction port 5 in the vacuum cavity 3 to realize the vacuum cavity 3.

[0058] Specifically, the opening of the textured vacuum bag is placed inside the vacuum chamber 3 and on the heat-sealing strip 4. The cover 2 is then placed on top, sealing the vacuum chamber 3 and pressing the opening of the textured vacuum bag tightly. At this point, the switch is turned on, and the vacuum pump motor operates to perform a vacuuming operation. The vacuum chamber 3 is connected to a linear pressure sensor via a gas pipeline. The linear pressure sensor can monitor the pressure inside the vacuum chamber 3 in real time and then feeds back the detected pressure value to the controller. The controller receives the pressure value and calculates it within a preset unit time. The pressure change value within T is equal to the preset pressure change value. Compare with P; if the actual pressure change is not higher than the preset pressure change value... If P is exceeded, the vacuum process continues. If P indicates that the liquid has begun to block the gas passage inside the textured vacuum bag, it means that the gas has been completely extracted. Therefore, a command to stop vacuuming is issued, and the heat sealing strip 4 is activated to heat and seal the bag.

[0059] When the heat sealing time reaches the last second, the sealing is basically completed. Control the start of the vacuum pump to start pumping air again, which increases the negative pressure in the vacuum chamber 3. The cover 2 and the seat 1 are sealed more tightly. The sealing strip or silicone strip around the vacuum chamber 3 presses the textured vacuum bag more tightly, which enhances the heat sealing effect. At the same time, it can also cool down the heat sealing strip 4 to prevent the heat sealing strip 4 from overheating.

[0060] The technical solution of this invention can effectively solve the problem of liquid overflow in the wet extraction working mode of existing vacuum sealing machines, such as... Figure 3 As shown, the textured vacuum bags sealed using existing vacuum sealing machines have significant liquid overflow at the bag opening, and there are many incomplete seals. This is mainly reflected in the fact that the texture of the bag body is still clearly visible. The main reason is that the liquid overflow lowers the temperature of the heat sealing strip, and the uneven heating of the heat sealing strip leads to incomplete heat sealing. This can easily cause leakage during long-term storage or transportation. Figure 4The vacuum sealing machine using the control method of this invention produces textured vacuum bags with no obvious liquid overflow at the bag opening, and the sealing strip is clear, uniform, and complete, resulting in a perfect seal. This invention eliminates the need for additional components such as solenoid valves or reverse air blowing structures, effectively reducing equipment costs. It achieves highly controllable and effective vacuum wet-heat sealing using only a linear pressure sensor combined with optimized control methods, preventing liquid overflow from contaminating the vacuum sealing machine, reducing cleaning steps, and effectively controlling the liquid volume inside the vacuum bag to match the added amount. From a commercial perspective, this invention has significant positive implications and value.

[0061] The vacuum heat sealing machine of the present invention can simultaneously have other conventional modes of dry sealing and vacuum sealing, which will not be described in detail here.

[0062] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the inventive concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for controlling vacuum wet-sealing of textured vacuum bags, characterized in that: Includes the following steps: After placing the textured vacuum bag containing liquid into the vacuum chamber, start the vacuum pump motor to perform vacuuming. Use the rated speed of the vacuum pump motor as the reference N0, and set the starting speed of the vacuum pump motor as N1. The speed of N1 is lower than the speed of N0. Use the starting speed N1 to drive the vacuum pump to evacuate the textured vacuum bag. During the vacuuming process, a linear pressure sensor continuously detects the pressure in the vacuum chamber and monitors the pressure changes within the vacuum chamber, with a preset unit time. T and the corresponding preset pressure change value are P, when detected in The actual pressure change within the vacuum chamber within the time range T is greater than the preset pressure change value. If P is selected, the vacuuming process will stop, and the heat sealing strip will be activated to heat seal the product. The preset heat sealing time is t1. When the heat sealing time reaches the last second of the preset heat sealing time t1, the vacuum pump motor is started at the rated speed N0 to strengthen the vacuum. The preset time for strengthening the vacuum is t2. After the strengthening vacuum time ends, the vacuum heat sealing is completed.

2. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: The starting speed N1 is 20-30% of the rated speed N0 of the vacuum pump motor.

3. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: Preset unit time T is 0.4-0.6s, and the preset pressure change value is... P is 4-8 kPa.

4. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: The preset time for enhanced vacuuming t2 is 2-3 seconds.

5. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: The starting speed N1 of the vacuum pump motor corresponds to the initial vacuuming speed S1, and the rated speed N0 corresponds to the speed for enhanced vacuuming S2. S2 is greater than S1, and the initial vacuuming speed S1 is 1.0-2.5 L / min.

6. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: The textured vacuum bag has a raised structure on at least one side of its inner surface, and the two inner sides have several gas channels corresponding to each other when vacuuming.

7. The vacuum wet-extraction heat-sealing control method for a textured vacuum bag according to claim 6, characterized in that: The vacuum pump motor, linear pressure sensor, and heat sealing strip are all electrically controlled by the controller. The controller continuously reads the pressure signal detected by the linear pressure sensor and calculates the pressure within a preset unit time. The actual pressure change value within T is compared with the preset pressure change value. When the liquid in the textured vacuum bag is drawn into the gas passage and blocks it, the pressure change in the vacuum chamber increases suddenly. The controller then stops the vacuum pump motor, thereby stopping the vacuuming process and initiating the heat sealing.

8. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: During the initial vacuuming process, when the speed is below the rated speed of the motor, the pressure inside the vacuum chamber is in the range of -3 to -5 kPa.

9. The vacuum wet-sealing control method for a textured vacuum bag according to claim 1, characterized in that: The linear pressure sensor detects the pressure inside the vacuum chamber every 0.1 seconds and feeds it back to the controller. The preset pressure change value refers to the pressure change within a preset unit time. Within the range of T, the pressure reached in the last 0.1s is subtracted from the pressure value detected in the first 0.1s, and the control logic is executed by the controller.

10. A vacuum heat-sealing machine utilizing the vacuum wet-extraction heat-sealing control method for a textured vacuum bag according to any one of claims 1-9, characterized in that: It includes a reversible base and a cover, which form a sealed vacuum cavity when closed together. A heat-sealing strip is provided on one side of the vacuum cavity. The base contains a controller, a vacuum pump with a motor, a linear pressure sensor, and a gas pipeline. The controller is electrically connected to the linear pressure sensor, the vacuum pump, and the heat-sealing strip. The gas pipeline connects the vacuum pump and the vacuum cavity.

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