A gas path structure in which a common vacuum pump replaces a high-oxygen vacuum pump

Abstract

The present invention discloses an air path structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump. The air path structure is connected to an upper mold cavity (1) and a lower mold cavity (2), and comprises a first compressed air path, a vacuum pump path, a fresh-keeping gas path, and a second compressed air path. The second compressed air path comprises a second compressed air pipeline. A solenoid valve E (11) is provided on the second compressed air pipeline. The second compressed air pipeline is connected to a pipeline connecting the fresh-keeping gas path and the vacuum pump path. The vacuum pump path is a vacuum pump path using an ordinary vacuum pump. The present invention adds an additional compressed air path to the ordinary vacuum pump path, thereby completely solving the adverse effects of high-concentration O2 on the vacuum pump.

Description

Technical Field

[0001] The invention relates to the technical field of food negative pressure packaging equipment, in particular to an air path structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump. Background Art

[0002] For food packaging equipment, especially negative pressure modified atmosphere packaging equipment, there is a process of first evacuating the upper and lower sealed chambers (also called upper and lower mold cavities, consisting of upper mold cavity 1 and lower mold cavity 2), and then filling the upper sealed chamber (upper mold cavity 1) with compressed air, and filling the lower sealed chamber (lower mold cavity 2) with fresh-keeping gas. For different packaged products, the fresh-keeping gas filled in the lower sealed chamber will be different. Among them, the proportion of products filled with fresh-keeping gas mixed in a certain proportion of O2+CO2 (generally 80% O2+20% CO2) is still relatively large. After the inflation is completed, the sealing film is pressed to the surface of the box in the lower mold cavity through the heating plate to seal it. Finally, a cutter is used to cut off the film around the box, the upper and lower cavities are opened, and the sealed box is taken out to complete a cycle and wait for the next cycle. Figure 1 The figure shows the structure of the existing hyperoxia pump air conditioning circuit, including the first compressed air circuit, the vacuum pump circuit and the fresh-keeping gas circuit. The first compressed air circuit is mainly composed of pipelines, solenoid valve A3 and pressure regulating valve A4. The vacuum pump circuit is mainly composed of pipelines, solenoid valve B5, solenoid valve C6 and vacuum pump 9 using hyperoxia pump. The fresh-keeping gas circuit is mainly composed of pipelines, solenoid valve D7 and pressure regulating valve B8. The whole process is as follows:

[0003] During operation: (In the initial state of the gas circuit, the solenoid valve A3, solenoid valve B5, solenoid valve C6, and solenoid valve D7 are all in the disconnected state)

[0004] 1. The upper mold cavity 1 and the lower mold cavity 2 are opened, and the box containing the product to be packaged in modified atmosphere is placed in it. At the same time, the sealing film has also been placed directly under the upper mold cavity 1;

[0005] 2. The upper mold cavity 1 and the lower mold cavity 2 are closed. Due to the presence of the film, the upper mold cavity 1 and the lower mold cavity 2 become two independent spaces;

[0006] 3. The vacuum pump 9 is turned on, and the solenoid valves B5 and C6 are opened to evacuate the upper mold cavity 1 and the lower mold cavity 2 respectively;

[0007] 4. When the vacuum degree of the upper mold cavity 1 and the lower mold cavity 2 reaches the set value, the solenoid valve B5 and the solenoid valve C6 are closed; the solenoid valve D7 is connected to fill the lower mold cavity 2 with fresh-keeping gas; the solenoid valve A3 is connected to fill the upper mold cavity 1 with compressed air;

[0008] 5. When the air volume in the upper mold cavity 1 and the lower mold cavity 2 reaches the set value, the solenoid valve A3 and the solenoid valve D7 are disconnected;

[0009] 6. The heating plate inside the upper mold cavity 1 presses down, pressing the sealing film to the surface of the box inside the lower mold cavity 2 and completely sealing it;

[0010] 7. The cutter inside the upper mold cavity 1 presses down to cut the film;

[0011] 8. Open the upper mold cavity 1 and the lower mold cavity 2, take out the sealed box in the lower mold cavity 2, and wait for the next box to be put in.

[0012] The above has completed a gas-controlled sealing process.

[0013] With respect to the lower mold cavity 2, after the last box is sealed with controlled atmosphere, there is still a lot of high-concentration fresh-keeping gas in the entire air circuit and the lower mold cavity 2. Therefore, during the next vacuuming cycle, these high-concentration fresh-keeping gases will be drawn into the vacuum pump 9 and then discharged. Due to the presence of O2, especially when the O2 ratio is greater than 21%, it is defined as a high-concentration O2. The lubricating grease, seals, etc. of ordinary vacuum pumps are easily rapidly oxidized by high-concentration O2, especially the lubricating grease will quickly fail, causing the function of ordinary vacuum pumps to decline rapidly and fail to meet the high vacuum requirements. At the same time, due to the presence of high oxygen, there is even a risk of explosion. Therefore, in the food controlled atmosphere packaging industry, special high-oxygen vacuum pumps (high-oxygen pumps) are generally used to cope with the use conditions of high-concentration O2 in the air circuit.

[0014] Since the dedicated high-oxygen vacuum pump uses special sealing materials and special lubricants, it is expensive, has high usage costs (lubricants need to be replaced regularly), and has a long procurement cycle, which greatly increases the overall cost for customers. Summary of the Invention

[0015] The purpose of the present invention is to design an air path structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump. By adding an additional compressed air path to the ordinary vacuum pump air path, the adverse effects of high-concentration O2 on the vacuum pump can be completely solved.

[0016] The present invention is achieved through the following technical solution: an air path structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump, is connected to the upper mold cavity and the lower mold cavity, including a first compressed air path, a vacuum pump path, a fresh-keeping gas path, and a second compressed air path. The second compressed air path includes a second compressed air pipeline, an electromagnetic valve E is provided on the second compressed air pipeline, and the second compressed air pipeline is connected to the pipeline connecting the fresh-keeping gas path and the vacuum pump path. The vacuum pump path is a vacuum pump path using an ordinary vacuum pump.

[0017] To further implement the present invention, the following configuration is particularly adopted: a pressure regulating valve C is further provided on the second compressed air pipeline, and the pressure regulating valve C is located on the air inlet side of the second compressed air pipeline.

[0018] In order to further better realize the present invention, the following setting structure is particularly adopted: the vacuum pump air circuit includes a vacuum pump, a pipeline, a solenoid valve B and a solenoid valve C. The vacuum pump is connected to the upper mold cavity and the lower mold cavity through pipelines respectively. The solenoid valve B is set on the pipeline connected to the upper mold cavity, and the solenoid valve C is set on the pipeline connected to the lower mold cavity.

[0019] In order to further better realize the present invention, the following setting structure is particularly adopted: the first compressed air circuit includes a first compressed air pipeline and a solenoid valve A and a pressure regulating valve A arranged on the first compressed air pipeline, and the pressure regulating valve A is arranged on the air inlet side of the first compressed air pipeline, and the first compressed air pipeline is connected to the pipeline between the solenoid valve B and the upper mold cavity.

[0020] In order to further better realize the present invention, the following setting structure is particularly adopted: the fresh-keeping gas circuit includes a fresh-keeping gas pipeline and a solenoid valve D and a pressure regulating valve B arranged on the fresh-keeping gas pipeline, and the pressure regulating valve B is arranged on the air inlet side of the fresh-keeping gas pipeline, and the fresh-keeping gas pipeline is connected to the pipeline between the solenoid valve C and the lower mold cavity.

[0021] In order to further better implement the present invention, the following configuration is particularly adopted: the second compressed air pipeline is connected to the fresh-keeping gas pipeline between the solenoid valve D and the pipeline.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] The present invention can make an outstanding contribution to the entire industry's transition from using dedicated high-oxygen pumps to ordinary vacuum pumps when high-concentration O2 packaging methods are rapidly popularized in the packaging industry, especially the food packaging industry.

[0024] The present invention reduces the equipment purchase cost: compared with the high price of the hyperoxia pump, it only needs to add an extra gas path on the basis of the ordinary vacuum pump: an extra 2-way solenoid valve and a pressure regulating valve.

[0025] The present invention reduces the cost of using the equipment: since an ordinary vacuum pump is adopted, only the ordinary vacuum pump oil needs to be replaced regularly, the price is moderate, and the purchase is convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a structural diagram of the vacuum exhaust gas circuit of the negative pressure packaging equipment in the prior art.

[0027] Figure 2 It is a structural schematic diagram of the present invention.

[0028] Among them, 1-upper mold cavity, 2-lower mold cavity, 3-solenoid valve A, 4-pressure regulating valve A, 5-solenoid valve B, 6-solenoid valve C, 7-solenoid valve D, 8-pressure regulating valve B, 9-vacuum pump, 11-solenoid valve E, 12-pressure regulating valve C. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below with reference to the examples, but the embodiments of the present invention are not limited thereto.

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0031] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms, etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0032] 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 the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0033] In the present invention, unless otherwise expressly specified or limited, terms such as "install," "connect," "connect," "set," "lay out," and "fix" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration. The specific means used are not limited to various conventional mechanical connection methods such as screw connections, interference fits, rivets, and thread-assisted connections. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0034] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0035] It is worth noting that: in this application, when certain known technologies or conventional technical means need to be applied in the field, the applicant may not specifically explain in the text what kind of technical means the known technologies and / or conventional technical means are. However, it cannot be considered that the technical solution of this application is unclear because the technical means are not specifically disclosed in the text.

[0036] Glossary:

[0037] A threaded auxiliary part refers to any connecting part including screws, screws, bolts, etc. used to connect two structures. In the following embodiments, the preferred threaded auxiliary part is a screw.

[0038] Example 1:

[0039] like Figure 2 As shown, an air path structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump is added. An additional compressed air path is added to the ordinary vacuum pump path, which can completely solve the adverse effects of high-concentration O2 on the vacuum pump. The structure is connected to the upper mold cavity 1 and the lower mold cavity 2, and includes a first compressed air path, a vacuum pump path, a fresh-keeping gas path, and a second compressed air path. The second compressed air path includes a second compressed air pipeline. An electromagnetic valve E11 is provided on the second compressed air pipeline. The second compressed air pipeline is connected to the pipeline connecting the fresh-keeping gas path and the vacuum pump path. The vacuum pump path is a vacuum pump path using an ordinary vacuum pump.

[0040] As a preferred setting scheme, the air circuit structure includes a first compressed air circuit, a vacuum pump circuit, a fresh-keeping gas circuit and a second compressed air circuit. The vacuum pump circuit is connected to the upper mold cavity 1 and the lower mold cavity 2. The first compressed air circuit and the fresh-keeping gas circuit are introduced into the upper mold cavity 1 and the lower mold cavity 2 through the vacuum pump circuit; the second compressed air circuit includes a second compressed air pipeline, on which an electromagnetic valve E11 is provided. The second compressed air pipeline is connected to the pipeline connecting the fresh-keeping gas circuit and the vacuum pump circuit. The vacuum pump circuit is a vacuum pump circuit using an ordinary vacuum pump.

[0041] Compared to the existing hyperoxia pump's gas conditioning circuit (conventional exhaust and inflation circuit), an additional gas circuit is added to the circuit for filling the gas containing high-concentration O2. This gas circuit is connected to the compressed air through a two-way solenoid valve (solenoid valve E11) or other on-off structure. During the high-concentration O2 inflation process, this gas circuit is closed. When the entire inflation and sealing and film cutting process is completed and the mold cavity is opened, the gas circuit is connected, and compressed air is used to inflate the pipe and cavity, filling the high-concentration O2 in the entire gas circuit with air, ultimately making the gas composition of the entire gas circuit consistent with the air composition. In this way, when the second cycle begins, the gas drawn in by the vacuum pump does not contain high-concentration O2, so a conventional vacuum pump can be used to replace the hyperoxia vacuum pump.

[0042] Example 2:

[0043] This embodiment is further optimized based on the above embodiment, and the parts that are the same as the above technical solutions will not be repeated here. Figure 2 As shown, in order to further better implement the present invention, the following setting structure is particularly adopted: a pressure regulating valve C12 is also provided on the second compressed air pipeline, and the pressure regulating valve C12 is located on the air inlet side of the second compressed air pipeline.

[0044] Correspondingly, in order to adjust the inflation flow, a pressure regulating valve C12 can be added to the inflation gas circuit to facilitate different inflation flow adjustments according to different sizes of pipelines and cavities.

[0045] Example 3:

[0046] This embodiment is further optimized based on any of the above embodiments, and the parts that are the same as the above technical solutions will not be repeated here. Figure 2 As shown, in order to better realize the present invention, the following setting structure is particularly adopted: the vacuum pump air circuit includes a vacuum pump 9, a pipeline, a solenoid valve B5 and a solenoid valve C6, the vacuum pump 9 is connected to the upper mold cavity 1 and the lower mold cavity 2 through the pipeline respectively, the solenoid valve B5 is set on the pipeline connected to the upper mold cavity 1, and the solenoid valve C6 is set on the pipeline connected to the lower mold cavity 2.

[0047] Example 4:

[0048] This embodiment is further optimized based on any of the above embodiments, and the parts that are the same as the above technical solutions will not be repeated here. Figure 2 As shown, in order to better realize the present invention, the following setting structure is particularly adopted: the first compressed air circuit includes a first compressed air pipeline and a solenoid valve A3 and a pressure regulating valve A4 arranged on the first compressed air pipeline, and the pressure regulating valve A4 is arranged on the air inlet side of the first compressed air pipeline, and the first compressed air pipeline is connected to the pipeline between the solenoid valve B5 and the upper mold cavity 1.

[0049] Example 5:

[0050] This embodiment is further optimized based on any of the above embodiments, and the parts that are the same as the above technical solutions will not be repeated here. Figure 2 As shown, in order to better realize the present invention, the following setting structure is particularly adopted: the fresh-keeping gas circuit includes a fresh-keeping gas pipeline and a solenoid valve D7 and a pressure regulating valve B8 arranged on the fresh-keeping gas pipeline, and the pressure regulating valve B8 is arranged on the air inlet side of the fresh-keeping gas pipeline, and the fresh-keeping gas pipeline is connected to the pipeline between the solenoid valve C6 and the lower mold cavity 2.

[0051] Example 6:

[0052] This embodiment is further optimized based on any of the above embodiments, and the parts that are the same as the above technical solutions will not be repeated here. Figure 2 As shown, in order to better implement the present invention, the following setting structure is particularly adopted: the second compressed air pipeline is connected to the fresh-keeping gas pipeline between the solenoid valve D7 and the pipeline.

[0053] Example 7:

[0054] This embodiment is further optimized based on any of the above embodiments, and the parts that are the same as the above technical solutions will not be repeated here. Figure 2 As shown, an air circuit structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump includes an upper mold cavity 1, a lower mold cavity 2, a solenoid valve A3, a pressure regulating valve A4, a solenoid valve B5, a solenoid valve C6, a solenoid valve D7, a pressure regulating valve B8, a vacuum pump 9, a solenoid valve E11, a pressure regulating valve C12, a first compressed air pipeline, a second compressed air pipeline, a pipeline, and a fresh-keeping gas pipeline; wherein, the vacuum pump 9, the pipeline, the solenoid valve B5, the solenoid valve C6 and pipe fittings such as a tee constitute the vacuum pump air circuit, the solenoid valve A3, the pressure regulating valve A4, the first compressed air pipeline and pipe fittings such as a tee constitute the first compressed air circuit, the solenoid valve D7, the pressure regulating valve B8, the fresh-keeping gas pipeline and pipe fittings such as a tee constitute the fresh-keeping gas circuit, the solenoid valve E11, the pressure regulating valve C12, the second compressed air pipeline and pipe fittings such as a tee constitute the second compressed air circuit, and all solenoid valves are two-way solenoid valves.

[0055] The vacuum pump 9 is connected to a tee through a pipe, and the upper mold cavity 1 and the lower mold cavity 2 are connected to the tee through pipes respectively. A solenoid valve B5 is arranged on the pipe between the upper mold cavity 1 and the tee, and a solenoid valve C6 is arranged on the pipe between the lower mold cavity 2 and the tee; a first compressed air pipe is arranged on the pipe between the solenoid valve B5 and the upper mold cavity 1 through the tee, and a solenoid valve A3 and a pressure regulating valve A4 are arranged on the first compressed air pipe, and the regulating valve A4 is located on the air inlet side of the first compressed air pipe; a fresh-keeping gas pipe is arranged on the pipe between the solenoid valve C6 and the lower mold cavity 2 through the tee, and a solenoid valve D7 and a pressure regulating valve B8 are arranged on the fresh-keeping gas pipe, and the regulating valve B8 is located on the air inlet side of the fresh-keeping gas pipe; the fresh-keeping gas pipe between the solenoid valve D7 and the pipe is connected to the second compressed air pipe through a tee, and a solenoid valve E11 and a pressure regulating valve C12 are arranged on the second compressed air pipe, and the regulating valve C12 is located on the air inlet side of the second compressed air pipe; the vacuum pump 9 adopts an ordinary vacuum pump.

[0056] During operation: (In the initial state of the gas circuit, the valves are as follows: solenoid valve A3, solenoid valve B5, solenoid valve C6, solenoid valve D7, and solenoid valve E11 are all in the disconnected state)

[0057] 1. The upper mold cavity 1 and the lower mold cavity 2 are opened, and the box containing the product to be packaged in modified atmosphere is placed in it. At the same time, the sealing film has been placed directly under the upper mold cavity 1;

[0058] 2. The upper mold cavity 1 and the lower mold cavity 2 are closed. Due to the presence of the film, the upper mold cavity 1 and the lower mold cavity 2 become two independent spaces;

[0059] 3. The vacuum pump 9 is turned on, and the solenoid valves B5 and C6 are opened to evacuate the upper mold cavity 1 and the lower mold cavity 2 respectively;

[0060] 4. When the vacuum degree of the upper mold cavity 1 and the lower mold cavity 2 reaches the set value, the solenoid valve B5 and the solenoid valve C6 are closed; the solenoid valve D7 is connected to fill the lower mold cavity 2 with fresh-keeping gas; the solenoid valve A3 is connected to fill the upper mold cavity 1 with compressed air;

[0061] 5. When the air volume in the upper mold cavity 1 and the lower mold cavity 2 reaches the set value, the solenoid valve A3 and the solenoid valve D7 are disconnected;

[0062] 6. The heating plate inside the upper mold cavity 1 presses down, pressing the sealing film to the surface of the box inside the lower mold cavity 2 and completely sealing it;

[0063] 7. The cutter inside the upper mold cavity 1 presses down to cut the film;

[0064] 8. Open the upper mold cavity 1 and the lower mold cavity 2, take out the sealed box in the lower mold cavity 1, and wait for the next box to be put in;

[0065] 9. While the upper mold cavity 1 and the lower mold cavity 2 are opened in step 8 above, the solenoid valve E11 is opened, and compressed air is passed through the second compressed air line to inflate the pipes connected to the lower mold cavity 2, the fresh-keeping gas pipe, and the interior of the lower mold cavity 2. This inflates the high-concentration O2 in the pipes connected to the lower mold cavity 2, the fresh-keeping gas pipe, and the interior of the lower mold cavity 2 into the air, ultimately diluting the gas composition in the entire air path to be consistent with that of air. Finally, the solenoid valve E11 is disconnected. In this way, when the second cycle begins, the gas drawn in by the vacuum pump 9 does not contain high-concentration O2.

[0066] 10. Place the box containing the product that needs modified atmosphere packaging and start the next cycle.

[0067] The above has completed a controlled atmosphere sealing process.

[0068] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention is within the scope of protection of the present invention.

Claims

1. An air path structure in which an ordinary vacuum pump replaces a high-oxygen vacuum pump, connected to an upper mold cavity (1) and a lower mold cavity (2), comprises a first compressed air path, a vacuum pump path, and a fresh-keeping gas path, characterized in that: The second compressed air circuit also includes a second compressed air pipeline, the second compressed air pipeline is provided with a solenoid valve E (11), the second compressed air pipeline is connected to the pipeline connecting the fresh-keeping gas pipeline and the vacuum pump pipeline, and the vacuum pump pipeline is a vacuum pump pipeline using an ordinary vacuum pump; A pressure regulating valve C (12) is also provided on the second compressed air pipeline, and the pressure regulating valve C (12) is located on the air inlet side of the second compressed air pipeline; The vacuum pump air circuit includes a vacuum pump (9), a pipeline, a solenoid valve B (5) and a solenoid valve C (6); the vacuum pump (9) is connected to the upper mold cavity (1) and the lower mold cavity (2) through the pipeline respectively; the solenoid valve B (5) is provided on the pipeline connected to the upper mold cavity (1), and the solenoid valve C (6) is provided on the pipeline connected to the lower mold cavity (2); The fresh-keeping gas circuit includes a fresh-keeping gas pipeline and a solenoid valve D (7) and a pressure regulating valve B (8) arranged on the fresh-keeping gas pipeline, wherein the pressure regulating valve B (8) is arranged on the air inlet side of the fresh-keeping gas pipeline, and the fresh-keeping gas pipeline is connected to the pipeline between the solenoid valve C (6) and the lower mold cavity (2); The first compressed air circuit includes a first compressed air pipeline, which is connected to the pipeline between the solenoid valve B (5) and the upper mold cavity (1); The second compressed air pipeline is connected to the fresh-keeping gas pipeline between the solenoid valve D (7) and the pipeline; When the entire inflation and sealing and film cutting process is completed and the mold cavity is opened, the second compressed air circuit is connected, and the compressed air inflates the pipeline and cavity, filling the high-concentration oxygen in the entire air circuit into the air, and finally making the gas composition in the entire air circuit consistent with the air composition.

2. The gas path structure of a common vacuum pump replacing a high-oxygen vacuum pump according to claim 1, characterized in that: The first compressed air circuit further comprises a solenoid valve A (3) and a pressure regulating valve A (4) arranged on the first compressed air pipeline, and the pressure regulating valve A (4) is arranged on the air inlet side of the first compressed air pipeline.

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