Adhesive spraying system

Abstract

The adhesive spraying system provided by the embodiment of the present application comprises a detection unit and a spraying unit, the detection unit comprises a first detection module and a second detection module, the first detection module and the second detection module each comprise three photoelectric detectors, each photoelectric detector can send a first signal or a second signal, the spraying unit comprises a first side nozzle and a second side nozzle, when the three photoelectric detectors in the second detection module all send the first signal or when the three photoelectric detectors in the first detection module all send the second signal, the first side nozzle stops spraying the adhesive, when the three photoelectric detectors in the first detection module all send the first signal or when the three photoelectric detectors in the second detection module all send the first signal, the second side nozzle stops spraying the adhesive, so that the adhesive is prevented from polluting the downstream, and meanwhile, slight deviation caused by factors such as flattening and slight wrinkling of the sheet material is avoided, unexpected stopping of spraying is avoided, and the product quality is affected.

Description

Technical Field

[0001] This invention relates to an adhesive spraying system. Background Technology

[0002] Disposable absorbent products, such as sanitary napkins, diapers, nursing pads, and disposable mattress pads, are widely used in people's daily lives. Disposable absorbent products are usually made up of several layers of sheet material, with adhesives usually placed between the sheet materials to make the layers of sheet material form a whole.

[0003] Typically, adhesive is sprayed onto the surface of sheet materials using a glue machine and nozzle module. To prevent the adhesive sprayed on the sheet material from affecting downstream production, such as the adhesive on the side unexpectedly adhering to the idler rollers, the adhesive edge usually does not extend to the edge of the sheet material. That is, there is a blank area without adhesive on both sides of the sheet material. In addition, to ensure that the sheet material can be stably sprayed with adhesive and stably bonded with other sheet materials, a guide device is also installed upstream of the nozzle module. However, the guide device usually has a correction range. In some cases, such as material rolls that are squeezed during transportation or material rolls that are unstable during production winding, even with the guide device, it is impossible to keep the sheet material stably on the center line during production. In such cases, it is very easy for the blank area to be sprayed with adhesive or for the adhesive to extend directly to the edge of the sheet material, resulting in adhesive contamination of downstream idler rollers / conveyor belts, etc. Summary of the Invention

[0004] Therefore, the present invention provides an adhesive spraying system to solve the above-mentioned technical problems.

[0005] An adhesive spraying system for spraying adhesive onto sheets includes a detection unit and a spraying unit.

[0006] The sheet material is configured to be continuously conveyed in a downstream direction, including a first edge and a second edge;

[0007] The detection unit includes a first detection module and a second detection module arranged symmetrically. Both the first detection module and the second detection module include three photoelectric detectors arranged equidistantly in sequence. Each photoelectric detector is configured to send a first signal when it detects a sheet and send a second signal when it does not detect a sheet. The photoelectric detector located in the middle of the first detection module is arranged near the first edge line, and the photoelectric detector located in the middle of the second detection module is arranged near the second edge line.

[0008] The spraying unit includes a first side nozzle located downstream of the detection unit and adjacent to the first side line, and a second side nozzle located adjacent to the second side line. The first side nozzle and the second side nozzle are configured to start spraying adhesive or stop spraying adhesive.

[0009] The first side nozzle is configured to stop spraying adhesive when all three photodetectors in the second detection module emit a first signal or when all three photodetectors in the first detection module emit a second signal. The second side nozzle is configured to stop spraying adhesive when all three photodetectors in the first detection module emit a first signal or when all three photodetectors in the second detection module emit a first signal.

[0010] In this module, the three photodetectors of the first detection module are, from the outside to the inside of the sheet, photodetector A, photodetector B, and photodetector C, respectively. In the second detection module, the three photodetectors are, from the outside to the inside of the sheet, photodetector A', photodetector B', and photodetector C', respectively. The first and second side nozzles are also configured to activate adhesive spraying when photodetectors A in the first detection module emit a second signal and when photodetectors A' in the second detection module emit a second signal.

[0011] The photodetector is a photocell.

[0012] The sheet material includes a normal conveying state and an offset state. When the sheet material is in the normal conveying state, the B photoelectric detector is located inside the first edge line and the B' photoelectric detector is located inside the second edge line. At the same time, the distance between the B photoelectric detector and the first edge line is 1-3mm, and the distance between the B' photoelectric detector and the second edge line is 1-3mm.

[0013] When the sheet is in normal conveying state, the distance between the B photodetector and the first edge line is equal to the distance between the B' photodetector and the second edge line.

[0014] The distances between photodetectors A and B, C and B, A' and B', and C' and B' are all equal and 5-10 mm.

[0015] Wherein, if the distance between the first detection module, the second detection module and the spraying unit is S, and the speed of sheet conveying is v, then the first side nozzle is configured as follows: when all three photoelectric detectors in the second detection module emit the first signal or when all three photoelectric detectors in the first detection module emit the second signal, the first side nozzle stops spraying adhesive at the S / v time point.

[0016] The adhesive spraying system also includes a waste rejection module. The distance between the waste rejection module and the first detection module and the second detection module is L. The waste rejection module is configured to operate at the L / v time point to reject the sheet material that has not been coated with adhesive.

[0017] Wherein, if the distance between the C photodetector and the B photodetector is defined as D, and the distance between the left side line and the first side line is defined as d, then D=d.

[0018] The first side nozzle sprays adhesive onto the sheet to form a first region, the width of which is an integer multiple of d.

[0019] Beneficial Effects: This invention provides an adhesive spraying system, including a detection unit and a spraying unit. The detection unit includes a first detection module and a second detection module, each of which includes three photoelectric detectors. Each photoelectric detector can send a first signal or a second signal. The spraying unit includes a first side nozzle and a second side nozzle. When all three photoelectric detectors in the second detection module send the first signal or when all three photoelectric detectors in the first detection module send the second signal, the first side nozzle stops spraying adhesive. When all three photoelectric detectors in the first detection module send the first signal or when all three photoelectric detectors in the second detection module send the first signal, the second side nozzle stops spraying adhesive. This avoids adhesive contamination downstream and also prevents slight deviations caused by factors such as sheet flattening and slight wrinkles from causing unexpected spraying stops and affecting product quality. Attached Figure Description

[0020] Figure 1 Front view of the adhesive spraying system of the present invention;

[0021] Figure 2 The first morphological diagram when the sheet material shifts;

[0022] Figure 3 The second morphological diagram when the sheet material shifts;

[0023] Sheet 10; First edge line 101; Second edge line 102; First detection module 11; A photoelectric detector 111; B photoelectric detector 112; C photoelectric detector 113; Second detection module 12; A' photoelectric detector 121; B' photoelectric detector 122; C' photoelectric detector 123; First side nozzle 21; Second side nozzle 22; Adhesive layer 30; First zone 31; Left side line 311; Second zone 32; Right side line 321. Detailed Implementation

[0024] This invention provides an adhesive spraying system for spraying adhesive onto a sheet 10, which is particularly suitable for the bonding or lamination of multiple sheets 10 in disposable absorbent products.

[0025] The adhesive can be acrylic adhesive, hot melt adhesive, starch adhesive, polyvinyl alcohol, etc., without limitation. At the same time, the amount sprayed on the sheet 10 can be determined according to actual needs, for example, it can be 0.1g / ㎡ to 15g / ㎡, specifically 0.1g / ㎡, 0.5g / ㎡, 1g / ㎡, 3g / ㎡, 5g / ㎡, 10g / ㎡, 15g / ㎡, etc., without specific limitations.

[0026] Furthermore, in the following description, the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing the invention and for 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 the invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] The adhesive spraying system includes a detection unit and a spraying unit, wherein the detection unit is used to detect the position of the sheet 10, and the spraying unit is used to spray adhesive onto the surface of the sheet 10.

[0028] Understandably, the adhesive spraying system also includes a sheet 10 supply unit for continuously feeding the sheet 10 to the detection unit and the spraying unit. The sheet 10 supply unit may include, for example, an unwinding device and a conveying device, to stably and continuously release and convey the sheet 10.

[0029] The sheet 10 can be a flexible sheet material with an extension direction. Typically, the extension direction of the sheet 10 is defined as the length direction, and the direction perpendicular to the length direction is the width direction. The width direction includes a first edge 101 and a second edge 102. Typically, the first edge 101 and the second edge 102 are arranged in parallel. In addition, the sheet 10 can be specifically toilet paper, non-woven fabric, PE film, etc., and there is no limitation here.

[0030] Please refer to Figure 1 The detection unit includes a first detection module 11 and a second detection module 12 arranged symmetrically. Both the first detection module 11 and the second detection module 12 include three photodetectors arranged equidistantly in sequence. Each photodetector is configured to send a first signal when it detects the sheet 10 and send a second signal when it does not detect the sheet 10. The photodetector located in the middle of the first detection module 11 is arranged near the first edge 101, and the photodetector located in the middle of the second detection module 12 is arranged near the second edge 102.

[0031] In this embodiment, the first detection module 11 includes photodetectors A 111, B 112, and C 113 arranged sequentially from the outside to the inside of the sheet 10. These three photodetectors are equidistant from each other. The first detection module 11 is correspondingly arranged with respect to the first edge line 101. The photodetector B 112 is the closest to the first edge line 101. The term "closest" means that among the photodetectors A 111, B 112, and C 113, the distance between photodetector B 112 and the first edge line 101 is the smallest. Similarly, the second detection module 12 includes photodetectors A' 121 arranged sequentially from the outside to the inside of the sheet 10. Photodetectors A111, B122, and C123 are also equidistantly arranged, and the spacing between the photodetectors in the second detection module 12 is equal to the spacing between the photodetectors in the first detection module 11. The second detection module 12 is arranged correspondingly to the second edge line 102. Photodetectors A111, B112, C113, A'121, B'122, and C'123 are all configured to detect whether the sheet 10 exists at the corresponding position, and send a first signal when the sheet 10 is detected, and send a second signal when the sheet 10 is not detected.

[0032] In a specific embodiment, the photodetector is a photodetector, more specifically, such as a conventional direct photodetector. A light emitter and a receiver are respectively arranged above and below the sheet 10. When the sheet 10 passes through the gap between the corresponding light emitter and receiver to form a light blockage, the photodetector detects the sheet 10 and emits a first signal. When the sheet 10 does not pass through the gap between the light emitter and receiver, no light blockage is formed, and the photodetector does not detect the sheet 10 and emits a second signal.

[0033] The spraying unit includes a first side nozzle 21 located downstream of the detection unit and adjacent to the first edge line 101, and a second side nozzle 22 located adjacent to the second edge line 102. The first side nozzle 21 and the second side nozzle 22 are configured to spray adhesive or stop spraying adhesive. It can be understood that the first side nozzle 21 and the second side nozzle 22 are actually nozzles located outside the sheet 10 in the spraying unit. In other embodiments, several main nozzles may also be provided between the first side nozzle 21 and the second side nozzle 22.

[0034] An adhesive layer 30 can be formed on the surface of the sheet 10 by the spraying unit. For ease of description, the adhesive layer 30 formed by the first side nozzle 21 is referred to as the first region 31, and the adhesive layer 30 formed by the second side nozzle 22 is referred to as the second region 32. The first region 31 includes the left side line 311, and the second region 32 includes the right side line 321. It can be understood that the left side line 311 is the edge line of the adhesive layer 30 that is closest to the first side line 101, and the right side line 321 is the edge line of the adhesive layer 30 that is closest to the second side line 102.

[0035] Understandably, when the sheet 10 moves continuously downstream, the first region 31 takes on a continuous rectangular shape, and similarly, the second region 32 also takes on a continuous rectangular shape.

[0036] Please refer to this as well. Figure 3 The first side nozzle 21 is configured as follows:

[0037] When all three photodetectors in the second detection module 12 emit the first signal or when all three photodetectors in the first detection module 11 emit the second signal, the first side nozzle 21 stops spraying adhesive. In this case, the adhesive sprayed by the first side nozzle 21 will not cover the first edge line 101.

[0038] Similarly, the second side nozzle 22 is configured as follows:

[0039] When all three photodetectors in the second detection module 12 emit the second signal or when all three photodetectors in the first detection module 11 emit the first signal, the second side nozzle 22 stops spraying adhesive. This also prevents the adhesive sprayed by the second side nozzle 22 from covering the second edge line 102, thereby preventing excess adhesive from flowing out and causing downstream contamination.

[0040] Furthermore, the sheet 10 includes a normal conveying state and an offset state. When the sheet 10 is in the normal conveying state, the B photoelectric detector 112 is located inside the first edge line 101, and the B' photoelectric detector 122 is located inside the second edge line 102. The term "inner side" means the middle area near the width direction of the sheet 10. At the same time, the distance between the B photoelectric detector 112 and the first edge line 101 is 1-3 mm, and the distance between the B' photoelectric detector 122 and the second edge line 102 is 1-3 mm. In this case, the displacement or width change caused by the tension or flattening effect of the sheet 10 itself can also meet the detection requirements. At the same time, when the sheet 10 is in the normal conveying state, the distance between the B photoelectric detector 112 and the first edge line 101 and the distance between the B' photoelectric detector 122 and the second edge line 102 are approximately equal.

[0041] Furthermore, the spacing between photodetector A 111 and photodetector B 112, the spacing between photodetector C 113 and photodetector B 112, the spacing between photodetector A' 121 and photodetector B' 122, and the spacing between photodetector C' 123 and photodetector B' 122 are all equal and all are 5-10 mm.

[0042] Furthermore, if the distance between the C photodetector 113 and the B photodetector 112 is defined as D, and the distance between the left side line 311 and the first side line 101 is defined as d, then D = d.

[0043] Please refer to this as well. Figure 2 The first side nozzle 21 is further configured as follows:

[0044] When both photodetectors A111 in the first detection module 11 emit the second signal and both photodetectors A'121 in the second detection module 12 emit the second signal, the first side nozzle 21 and the second side nozzle 22 will start spraying adhesive.

[0045] In this case, the spraying unit is able to continuously form an adhesive layer 30 on the surface of the sheet 10.

[0046] Furthermore, the width of the first region 31 is greater than d.

[0047] Furthermore, the width of the first region 31 is an integer multiple of d.

[0048] Furthermore, if the distance between the first detection module 11, the second detection module 12, and the spraying unit is S, and the speed of the sheet 10 conveying is v, then the first side spray head 21 is configured as follows:

[0049] When all three photodetectors in the second detection module 12 emit the first signal or when all three photodetectors in the first detection module 11 emit the second signal, the first side nozzle 21 stops spraying adhesive at the S / v time point. In this case, the adhesive sprayed by the first side nozzle 21 will not cover the first edge line 101.

[0050] Furthermore, the adhesive spraying system also includes a rejection module, which is configured to reject sheets 10 that are not coated with adhesive. The distance between the rejection module and the first detection module 11 and the second detection module 12 is L. The rejection module is configured to operate at the L / v time point to reject the sheets 10 that are not coated with adhesive.

[0051] Understandably, in this invention, when all three photodetectors in the second detection module 12 emit the first signal or when all three photodetectors in the first detection module 11 emit the second signal, it is necessary to indicate that the offset distance of the sheet 10 is such that the adhesive sprayed by the spraying unit will cover the second edge line. In this case, spraying should be stopped to avoid adhesive contamination downstream. This arrangement can also avoid slight offsets caused by factors such as the sheet itself flattening or slight wrinkles, which could lead to unexpected stops of spraying and affect product quality.

[0052] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. An adhesive spraying system for spraying adhesive onto sheets, comprising a detection unit and a spraying unit, characterized in that: The sheet material is configured to be continuously conveyed in a downstream direction, including a first edge and a second edge; The detection unit includes a first detection module and a second detection module arranged symmetrically. Both the first detection module and the second detection module include three photoelectric detectors arranged equidistantly in sequence. Each photoelectric detector is configured to send a first signal when it detects a sheet and send a second signal when it does not detect a sheet. The photoelectric detector located in the middle of the first detection module is arranged near the first edge line, and the photoelectric detector located in the middle of the second detection module is arranged near the second edge line. The spraying unit includes a first side nozzle located downstream of the detection unit and adjacent to the first side line, and a second side nozzle located adjacent to the second side line. The first side nozzle and the second side nozzle are configured to start spraying adhesive or stop spraying adhesive. The first side nozzle is configured to stop spraying adhesive when all three photodetectors in the second detection module emit a first signal or when all three photodetectors in the first detection module emit a second signal. The second side nozzle is configured to stop spraying adhesive when all three photodetectors in the first detection module emit a first signal or when all three photodetectors in the second detection module emit a second signal.

2. The adhesive spraying system as claimed in claim 1, characterized in that, The three photodetectors of the first detection module are, from the outside to the inside of the sheet, photodetector A, photodetector B, and photodetector C. The three photodetectors of the second detection module are, from the outside to the inside of the sheet, photodetector A', photodetector B', and photodetector C'. The first and second side nozzles are also configured to activate adhesive spraying when photodetectors A in the first detection module emit a second signal and when photodetectors A' in the second detection module emit a second signal.

3. The adhesive spraying system as described in claim 1, characterized in that, The photodetector is a photocell.

4. The adhesive spraying system as described in claim 2, characterized in that, The sheet material includes a normal conveying state and an offset state. When the sheet material is in the normal conveying state, the B photoelectric detector is located inside the first edge line and the B' photoelectric detector is located inside the second edge line. At the same time, the distance between the B photoelectric detector and the first edge line is 1-3mm, and the distance between the B' photoelectric detector and the second edge line is 1-3mm.

5. The adhesive spraying system as described in claim 4, characterized in that, When the sheet is in normal conveying state, the distance between the B photodetector and the first edge line is equal to the distance between the B' photodetector and the second edge line.

6. The adhesive spraying system as claimed in claim 4, characterized in that, The spacing between photodetectors A and B, between photodetectors C and B, between photodetectors A' and B', and between photodetectors C' and B' are all equal and are all 5-10 mm.

7. The adhesive spraying system as claimed in claim 6, characterized in that, If the distance between the first detection module, the second detection module and the spraying unit is S, and the speed of sheet conveying is v, then the first side nozzle is configured as follows: when all three photodetectors in the second detection module emit the first signal or when all three photodetectors in the first detection module emit the second signal, the first side nozzle stops spraying adhesive at the S / v time point.

8. The adhesive spraying system as claimed in claim 7, characterized in that, The adhesive spraying system also includes a rejection module. The distance between the rejection module and the first detection module and the second detection module is L. The rejection module is configured to operate at the L / v time point to reject the sheet material that has not been coated with adhesive.

9. The adhesive spraying system as claimed in claim 7, characterized in that, If we define the distance between photodetector C and photodetector B as D, and the distance between the left side line and the first side line as d, then D = d.

10. The adhesive spraying system as claimed in claim 9, characterized in that, The first side nozzle sprays adhesive onto the sheet to form a first region, the width of which is an integer multiple of d.

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