A leak-proof valve pocket
By using a spring sheet structure and adhesive parts in the valve bag, the problem of dust leakage during filling is solved, achieving rapid sealing and efficient material closure, improving the safety of the production environment and ease of operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SICHUAN SHENGZUN NEW MATERIALS CO LTD
- Filing Date
- 2025-06-27
- Publication Date
- 2026-05-29
AI Technical Summary
Existing valve bags are prone to dust leakage when filling powdery materials because the valve opening is not completely sealed, which can pollute the production workshop and affect the health of workers, as well as cause problems with inadequate sealing.
A leak-proof valve bag is designed with a spring-loaded structure, including an upper valve plate and a lower valve plate. The spring-loaded valve plate extends laterally between the protective layer and the inner liner layer. During filling, it elastically bends to store energy, and after filling, it quickly returns to a straight position to drive the valve plate to close. The seal is achieved through the adhesive part and the release paper.
It enables the valve to close quickly at the moment of filling, reducing or eliminating material leakage, avoiding dust pollution and poor sealing, and improving sealing performance and operating efficiency.
Smart Images
Figure CN224297814U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of product packaging, and more specifically, it relates to a leak-proof valve bag. Background Technology
[0002] Valve bags are environmentally friendly packaging containers for filling powdery or granular materials (such as chemical raw materials, food additives, building materials, etc.) through a valve opening at the top or bottom. After filling, the bag is cubic in shape, facilitating stacking and transportation, and features moisture protection, reduced dust leakage, and improved storage efficiency. They can be classified by material: plastic valve bags, paper valve bags, and composite material valve bags. Current valve bag sealing technologies mainly rely on three methods: self-sealing, which relies on the weight of the material to close the valve opening; low cost but weak sealing performance; and heat sealing, which uses external heating for sealing; simple operation, but the adhesive layer of composite material valve bags is prone to hydrolysis and embrittlement in humid and hot environments. Ultrasonic sealing provides an airtight seal, preventing moisture and dust, but is more expensive. When filling powdery materials or materials that easily generate dust with a valve bag at the top valve opening, because the valve bag is in an upright position, there is still space at the top. The material does not severely compress the valve opening to completely seal it, leaving a channel for communication with the outside. If the valve is not closed during the extraction of the feed pipe, powdery material can easily leak out the moment the feed pipe is extracted. The leaked dust will contaminate the production workshop and adversely affect workers. At the same time, the leaked dust can easily adhere to the feed channel inside the valve, and the presence of dust at the interface can easily cause poor sealing during hot air or ultrasonic sealing. Utility Model Content
[0003] The purpose of this invention is to provide a leak-proof valve bag, which reduces or eliminates material leakage.
[0004] The above-mentioned technical objective of this utility model is achieved through the following technical solution: a leak-proof valve bag, the valve bag including a bag body and a valve opening; the valve opening is disposed on the bag body; the valve opening is used to fill the bag with material; the valve opening is formed by a valve plate; the valve plate includes a protective layer and an inner liner layer; the valve opening includes an upper valve plate and a lower valve plate; the upper valve plate and the lower valve plate are connected on both sides to form the valve opening; the upper valve plate and the lower valve plate are connected to form a feeding channel for the valve opening; the feeding channel includes an inner opening and an outer opening; the inner opening is disposed inside the bag body; the outer opening is disposed outside the bag body; the inner liner layer is located inside the feeding channel; the protective layer is located outside the feeding channel; it also includes a rebound sheet; the rebound sheet is disposed between the protective layer and the inner liner layer; the rebound sheet extends laterally through the upper valve plate and / or the lower valve plate.
[0005] Furthermore, the spring sheet includes a first spring sheet and a second spring sheet; the first spring sheet and the second spring sheet are respectively disposed on the upper valve plate and the lower valve plate; the first spring sheet is located after the second spring sheet in the feed channel.
[0006] Furthermore, the valve plate is integrally formed; a fold line is provided in the middle of the valve plate, and an upper valve plate and a lower valve plate are respectively on both sides of the fold line; an adhesive edge is provided on the side of the lower valve plate away from the upper valve plate; an adhesive area is provided on the protective layer of the upper valve plate away from the lower valve plate; the adhesive edge is connected to the adhesive area.
[0007] Furthermore, the valve plate is provided with a spring-loaded portion and an adhesive portion; the adhesive portion is located in the feed channel near the outer opening area; the spring-loaded portion is located in the feed channel near the inner opening area; the spring-loaded piece is located inside the spring-loaded portion; an adhesive layer is provided on the adhesive portion; the adhesive layer is located on the side of the inner liner layer away from the protective layer; and it also includes a release paper, which covers the adhesive layer.
[0008] Furthermore, the adhesive portion includes a first adhesive portion and a second adhesive portion; the first adhesive portion and the second adhesive portion are respectively disposed on the upper valve plate and the lower valve plate; the first adhesive portion and the second adhesive portion are connected laterally; and one end of the release paper is provided with a tear tab.
[0009] Furthermore, the valve plate also includes a barrier layer; the barrier layer is disposed between the protective layer and the inner liner layer.
[0010] Furthermore, the valve bag is formed by a sealing sheet, which unfolds into a cubic shape; the sealing sheet includes a front sealing sheet, a back sealing sheet, a left sealing sheet, a right sealing sheet, a top sealing sheet, and a bottom sealing sheet; the valve opening is located on the right sealing sheet near the top sealing sheet; inside the bag body; the upper valve plate of the valve opening is connected to the top sealing sheet.
[0011] Furthermore, both the sealing plate and the valve plate include a protective layer, a barrier layer, and an inner liner layer; the barrier layer is disposed between the protective layer and the inner liner layer; the protective layer is made of polypropylene woven fabric or kraft paper; the barrier layer is made of one of aluminum foil, aluminized film, or high-barrier co-extruded film; and the inner liner layer is made of polyethylene film.
[0012] In summary, this utility model has the following beneficial effects: at the moment the filling tube is pulled out, the rebound sheet automatically returns to a straight state from a bent state, driving the upper valve plate and the lower valve plate to quickly close the feeding channel, reducing or eliminating material leakage. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the valve pocket in its folded state.
[0014] Figure 2 This is a cross-sectional view of the valve pocket in its unfolded state.
[0015] Figure 3 This is a schematic diagram of the valve port.
[0016] Figure 4 yes Figure 3 Enlarged view at point A
[0017] Figure 5 yes Figure 3 Enlarged view at point B
[0018] Figure 6 This is a diagram showing the valve opening being pushed open by the feed pipe.
[0019] Figure 7 This is a schematic diagram of the valve port unfolding.
[0020] In the diagram: 1. Bag body; 2. Valve opening; 21. Protective layer; 211. Adhesive area; 22. Lining layer; 221. Adhesive edge; 23. Barrier layer; 24. Rebound sheet; 241. First rebound sheet; 242. Second rebound sheet; 31. Upper valve plate; 32. Lower valve plate; 33. Fold line; 4. Adhesive part; 41. Adhesive layer; 42. Release paper. Detailed Implementation
[0021] To make the technical problems, technical solutions and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.
[0022] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly or indirectly attached to that other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to that other component. This "connection" is not limited to a fixed connection or a movable connection; the specific connection method should be determined based on the specific technical problem to be solved.
[0023] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0024] 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0025] Example:
[0026] A leak-proof valve bag includes a bag body 1 and a valve opening 2; the valve opening 2 is disposed on the bag body 1; the valve opening 2 is used to fill the bag with material; the valve opening 2 is formed by a valve plate; the valve plate includes a protective layer 21 and an inner liner 22; the valve opening 2 includes an upper valve plate 31 and a lower valve plate 32; the upper valve plate 31 and the lower valve plate 32 are connected on both sides to form the valve opening 2; the upper valve plate 31 and the lower valve plate 32 form a feeding channel for the valve opening 2; the feeding channel includes an inner opening and an outer opening; the inner opening is disposed inside the bag body 1; the outer opening is disposed outside the bag body 1; the inner liner 22 is located inside the feeding channel; the protective layer 21 is located outside the feeding channel; and a spring sheet 24 is also included; the spring sheet 24 is disposed between the protective layer 21 and the inner liner 22; the spring sheet 24 laterally penetrates the upper valve plate 31 and / or the lower valve plate 32. Figure 6 During filling, the feed pipe is inserted into the feed channel from the outer opening, squeezing the upper valve plate 31 and the lower valve plate 32, forcing the spring sheet 24 to undergo elastic bending deformation. During bending, the spring sheet 24 stores elastic potential energy, while the protective layer 21 and the inner liner layer 22 are stretched to form a channel. After the feed pipe is inserted, the material is smoothly conveyed into the bag body 1. After filling, the feed pipe is pulled out, and the spring sheet 24, freed from external force constraint, quickly returns to a straight state, driving the upper valve plate 31 and the lower valve plate 32 to close synchronously. After closing, the spring sheet 24 continuously provides lateral prestress, maintaining a zero-gap state at the valve opening 2 even if the bag body 1 is stacked, squeezed, or shaken, preventing later "creep leakage." When the spring sheet 24 closes, it pushes the inner liner layer 22 to cover the inner wall of the feed channel, sealing residual dust inside the bag body 1 and preventing contamination at the heat-sealing interface.
[0027] Optionally, the rebound sheet 24 is made of shape memory alloy, preferably a nickel-titanium shape memory alloy. Using a shape memory alloy results in a faster rebound speed and can more effectively reduce dust leakage.
[0028] Optionally, the spring sheet 24 is made of plastic material, preferably thermoplastic polyester. Using thermoplastic polyester is less expensive than using shape memory alloys and makes it easier to thermally bond with the protective layer 21 and the inner liner layer 22.
[0029] Preferably, the thickness of the spring sheet 24 is 0.1~0.5mm.
[0030] Preferably, the protective layer 21 and the inner lining layer 22 are bonded together by adhesive bonding; the position of the spring sheet 24 is not easily slipped. Optionally, the protective layer 21 and the inner lining layer 22 are bonded together by hot pressing.
[0031] Preferred, such as Figure 3As shown, the spring sheet 24 includes a first spring sheet 241 and a second spring sheet 242; the first spring sheet 241 and the second spring sheet 242 are respectively disposed on the upper valve plate 31 and the lower valve plate 32; in the feeding channel, the first spring sheet 241 is located after the second spring sheet 242; that is, the first spring sheet 241 is closer to the inner opening, and the second spring sheet 242 is closer to the outer opening. When the filling tube is inserted, the second spring sheet 242 deforms first to absorb the impact, and the first spring sheet 241 is subsequently compressed to store energy, forming a relay mechanism of "buffering first and then storing energy". When the filling tube is withdrawn, the first spring sheet 241 rebounds first to drive the valve plate to close inward, forming the main sealing surface; the second spring sheet 242 delays its reset: filling the micro gaps caused by material residue or air pressure fluctuations, realizing secondary sealing. Even when the material inside the bag is small and cannot effectively compress the valve port 2, this solution ensures that the valve port 2 remains completely closed by the cooperation of the first and second spring plates 241 and 242, thus avoiding leakage caused by insufficient gravity in traditional valve ports 2. Based on this technical solution, those skilled in the art will be motivated to interchange the positions of the first and second spring plates 241 and 242 to achieve the same technical effect; therefore, interchangering their positions constitutes an equivalent technical solution.
[0032] In one possible embodiment, to address the cost issue of valve plate molding, such as... Figure 7 As shown, the valve plate is integrally formed; a fold line 33 is provided in the middle of the valve plate, with an upper valve plate 31 and a lower valve plate 32 on both sides of the fold line 33; an adhesive edge 221 is provided on the side of the lower valve plate 32 away from the upper valve plate 31; an adhesive area 211 is provided on the protective layer 21 of the upper valve plate 31 away from the lower valve plate 32; the adhesive edge 221 is connected to the adhesive area 211. In this embodiment, the valve plate is integrally formed, folded along the fold line 33 in the middle of the valve plate, and the far ends of the upper valve plate 31 and the lower valve plate 32 are bonded together to form the valve port 2. The unbonded part 4 in the middle forms a feeding channel. The integral forming and the fold line 33 replace the assembly of multiple parts, eliminate leakage paths, and only one edge needs to be bonded to complete the production of the valve port 2, which greatly improves efficiency and reduces costs.
[0033] Optionally, the bonding area 211 and the bonding edge 221 can be connected by adhesive bonding or by hot pressing.
[0034] Preferably, the inner lining layer 22 and the protective layer 21 are arranged in a direction perpendicular to the fold line 33; the exposed protective layer 21 of the lower valve plate 32 forms an adhesive edge 221; the exposed inner lining layer 22 of the upper valve plate 31 forms an adhesive area 211. After folding along the fold line 33, the adhesive edge 221 adheres to the adhesive area 211, forming the valve port 2. This design ensures that the valve port 2 is uniform in all directions, eliminating the problem of thicker areas in the valve port 2, avoiding stress concentration, and increasing the strength of the valve port 2.
[0035] In one possible embodiment, to solve the problem of sealing valve port 2, such as... Figure 5 what Figure 7 As shown, the valve plate is provided with a spring-loaded part and an adhesive part 4; the adhesive part 4 is located in the area near the outer opening of the feed channel; the spring-loaded part is located in the area near the inner opening of the feed channel; the spring-loaded piece 24 is located inside the spring-loaded part; an adhesive layer 41 is provided on the adhesive part 4; the adhesive layer 41 is located on the side of the inner liner 22 away from the protective layer 21; it also includes a release paper 42, which covers the adhesive layer 41. For easily oxidized materials, in order to achieve a better sealing effect, the upper valve plate 31 and the lower valve plate 32 are bonded together by setting the adhesive part 4 to form a sealed area, thereby sealing the material inside the bag 1. In use, the release paper 42 is first torn off, and then the upper valve plate 31 and the lower valve plate 32 are pressed to seal, which is simple to operate. At the same time, due to the presence of the release paper 42, even if the outer wall of the feed pipe or overflowing powder enters the feed channel, it will not affect the bonding effect of the adhesive area 211. After removing the release paper 42, you can directly press and bond the components. This method is highly efficient and less expensive than ultrasonic or hot pressing, eliminating the need for additional ultrasonic or hot pressing equipment.
[0036] Preferably, the adhesive portion 4 includes a first adhesive portion and a second adhesive portion; the first adhesive portion and the second adhesive portion are respectively disposed on the upper valve piece 31 and the lower valve piece 32; the first adhesive portion and the second adhesive portion are laterally connected; one end of the release paper 42 is provided with a tear tab. The first adhesive portion and the second adhesive portion are laterally connected, so that after the upper valve piece 31 and the lower valve piece 32 are folded in half, the positions of the first adhesive portion and the second adhesive portion correspond, which can better complete the bonding and isolate air.
[0037] Optionally, the adhesive layer 41 is one of fluorinated modified epoxy, fluorosilicone sealant, polyurethane adhesive, and acrylic structural adhesive. Preferably, fluorinated modified epoxy is used to balance corrosion resistance, temperature adaptability, and cost, covering most packaging scenarios.
[0038] In one possible embodiment, to address the packaging issues of photosensitive materials, easily oxidized materials, and easily absorbent materials during chemical packaging, the valve plate further includes a barrier layer 23; the barrier layer 23 is disposed between the protective layer 21 and the inner liner layer 22. The barrier layer 23 is made of a suitable material depending on the type of pre-packaged product.
[0039] In one possible embodiment, to reduce dead corners within the bag body 1 and prevent localized material accumulation, the valve bag is formed by a sealing plate, unfolding into a cubic shape. The sealing plate includes a front sealing plate, a back sealing plate, a left sealing plate, a right sealing plate, a top sealing plate, and a bottom sealing plate. The valve port 2 is located on the right sealing plate near the top sealing plate, inside the bag body 1. The upper valve plate 31 of the valve port 2 is connected to the top sealing plate. After the upper valve plate 31 is connected to the top sealing plate, the valve port 2 can better withstand the pressure of the material when filled. Furthermore, it eliminates the gap between the upper valve plate 31 and the top sealing plate, preventing material from hiding in these gaps during pouring.
[0040] Optionally, both the sealing sheet and the valve sheet include a protective layer 21, a barrier layer 23, and an inner liner layer 22; the barrier layer 23 is disposed between the protective layer 21 and the inner liner layer 22. The protective layer is made of polypropylene woven fabric or kraft paper. Polypropylene woven fabric has high tensile strength in both warp and weft directions, strong tear resistance, and is resistant to repeated bending, making it durable after containing materials; it is also resistant to acids, alkalis, and organic solvents, and resistant to microbial erosion. Kraft paper has biodegradable wood fibers, conforming to the trend of green packaging, and its surface roughening treatment improves ink adhesion and facilitates printing.
[0041] The barrier layer is made of one of the following: aluminum foil, aluminized film, or high-barrier co-extruded film. Aluminum foil can completely block light, air, and water, but it is expensive. Although aluminized film has lower air permeability than aluminum foil, it has good flexibility and low cost. The high-barrier co-extruded die uses multi-layer co-extrusion (such as PE / Tie / EVOH / Tie / PE) to balance heat-sealing and barrier properties.
[0042] The inner lining is made of polyethylene film. Polyethylene film is resistant to acids, alkalis, and greases, is non-toxic and odorless, has good sealing performance, and can be widely used.
[0043] Optionally, to address the issue of drug transportation, valve bags can be made using kraft paper, aluminum foil, and an LLDPE liner. The kraft paper is compression-resistant, the aluminum foil provides absolute barrier properties, and the LLDPE is heat-sealed for moisture protection.
[0044] Optionally, to solve the problem of fertilizer packaging and transportation, a combination of PP woven fabric + aluminized film + HDPE inner lining is used. The woven fabric is tear-resistant, the aluminized film is oxygen-barrier and moisture-proof, and the HDPE is chemically resistant.
[0045] Optionally, to address food packaging and transportation issues, a biodegradable kraft paper + EVOH co-extruded film + LDPE liner can be used; the kraft paper is compostable, EVOH is a bio-based material, and LDPE is recyclable.
[0046] In summary, the leak-proof valve bag provided in the embodiments has the following beneficial technical effects:
[0047] 1. Driven by the elastic potential energy of the double rebound sheet, the valve port closes in milliseconds after filling and continuously provides lateral prestress, effectively resisting stacking compression and bag shaking, eliminating the problems of "creep leakage" and dust residue caused by insufficient gravity in traditional valve ports.
[0048] 2. For easily oxidized materials, a chemical bond seal is formed by pre-applying an adhesive layer to the bonding area; combined with a cubic bag structure without dead corners (the valve port is directly connected to the top sealing plate), material hiding and residue are prevented.
[0049] This specific embodiment is merely an explanation of the present utility model and is not intended to limit the present utility model. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present utility model, they are protected by patent law.
Claims
1. A leak-proof valve bag, characterized in that: The valve bag includes a bag body and a valve opening; the valve opening is disposed on the bag body; the valve opening is used to fill the bag with material; The valve port is formed by a valve plate; the valve plate includes a protective layer and an inner liner layer; the valve port includes an upper valve plate and a lower valve plate; the upper and lower valve plates are connected on both sides to form the valve port; the upper and lower valve plates form the feed channel of the valve port; the feed channel includes an inner opening and an outer opening; the inner opening is located inside the bag body; the outer opening is located outside the bag body; the inner liner layer is located inside the feed channel; the protective layer is located outside the feed channel; it also includes a spring sheet; the spring sheet is located between the protective layer and the inner liner layer; the spring sheet passes laterally through the upper valve plate and / or the lower valve plate.
2. The leak-proof valve bag according to claim 1, characterized in that: The spring sheet includes a first spring sheet and a second spring sheet; the first spring sheet and the second spring sheet are respectively disposed on the upper valve plate and the lower valve plate; the first spring sheet is located after the second spring sheet in the feed channel.
3. The leak-proof valve bag according to claim 2, characterized in that: The valve plate is integrally formed; a fold line is provided in the middle of the valve plate, and an upper valve plate and a lower valve plate are respectively on both sides of the fold line; an adhesive edge is provided on the side of the lower valve plate away from the upper valve plate; an adhesive area is provided on the protective layer of the upper valve plate away from the lower valve plate; the adhesive edge is connected to the adhesive area.
4. A leak-proof valve bag according to claim 3, characterized in that: The valve plate is provided with a spring-loaded part and an adhesive part; the adhesive part is located in the area near the outer opening of the feed channel; the spring-loaded part is located in the area near the inner opening of the feed channel; the spring-loaded piece is located inside the spring-loaded part; An adhesive layer is provided on the bonding part; the adhesive layer is located on the side of the inner lining layer away from the protective layer; it also includes release paper, which covers the adhesive layer.
5. A leak-proof valve bag according to claim 4, characterized in that: The adhesive portion includes a first adhesive portion and a second adhesive portion; the first adhesive portion and the second adhesive portion are respectively disposed on the upper valve plate and the lower valve plate; the first adhesive portion and the second adhesive portion are connected laterally; one end of the release paper is provided with a tear tab.
6. A leak-proof valve bag according to claim 5, characterized in that: The valve plate also includes a barrier layer; the barrier layer is disposed between the protective layer and the inner liner.
7. A leak-proof valve bag according to claim 5, characterized in that: The valve bag is formed by a sealing sheet, which unfolds into a cubic shape; the sealing sheet includes a front sealing sheet, a back sealing sheet, a left sealing sheet, a right sealing sheet, a top sealing sheet, and a bottom sealing sheet; the valve opening is located on the right sealing sheet near the top sealing sheet; inside the bag body; the upper valve plate of the valve opening is connected to the top sealing sheet.
8. A leak-proof valve bag according to claim 7, characterized in that: Both the sealing plate and the valve plate include a protective layer, a barrier layer, and an inner liner layer; the barrier layer is disposed between the protective layer and the inner liner layer; The protective layer is made of polypropylene woven fabric or kraft paper; the barrier layer is made of aluminum foil, aluminized film, or high-barrier co-extruded film; and the inner liner is made of polyethylene film.