Curtain type coating die head
By designing the curtain coating die head, the structure of the buffer chamber and arc-shaped guide part is used to achieve uniform extrusion and dripping of raw materials, solving the problem when the die head comes into contact with the elastic or porous substrate, and forming a uniform and dense coating.
Patent Information
- Application Number
- CN202411768851.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-03-14
AI Technical Summary
When existing coating die heads come into contact with elastic substrates or porous substrates, they will affect the tension balance of the substrate and the lip of the die head is prone to wear.
A curtain coating die head is designed, through the inclined structure of the upper and lower dies and the design of the buffer chambers, the raw materials are buffered in the primary and secondary buffer chambers, and are uniformly extruded and dripped onto the substrate through the extrusion channel and the arcuate guide.
The die head does not contact the substrate, and the material slides down through its own gravity to form a uniform and dense coating, avoiding the influence of substrate tension balance and die wear.
Smart Images
Figure CN119608494A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of coating die heads, in particular to a curtain coating die head. Background Art
[0002] Compared with the standard hot melt adhesive coating die head, which is in direct contact with the substrate during coating, for elastic substrates such as PU, TPU film, stretch fabric and other substrates, the contact between the die head and the substrate will affect the tension balance of the substrate. For porous substrates and rough surface substrates, such as spunlace fabrics for medical tapes, velvet for wiring harness tapes, textile fabrics, kraft paper for kraft paper tapes, sandpaper and other substrates, the contact between the die head and the substrate will cause the die head lip to wear. Therefore, it is necessary to design a die head that does not contact the substrate. Summary of the invention
[0003] In view of the above problems, the present invention aims to provide a curtain coating die head, which does not contact the substrate, and after the material is extruded, it slides to the surface of the substrate by its own gravity to form a uniform and dense coating on the surface of the substrate.
[0004] The technical solution of the present invention is a curtain coating die head, characterized in that: it includes an upper die and a lower die with the front end inclined upward, the upper die and the rear part of the lower die are connected as a whole by a locking screw, the left and right sides of the upper die and the lower die are respectively provided with a left plate assembly and a right plate assembly, the rear side of the lower die is provided with a feed port, the middle area of the top surface of the lower die is provided with a primary buffer chamber along the width direction, the bottom surface of the primary buffer chamber is connected with the feed port through a feed channel, the top surface of the lower die on the front side of the primary buffer chamber is provided with an extrusion channel, the top surface of the lower die is located at the front side of the primary buffer chamber and is provided with a secondary buffer chamber along the width direction, the bottom surface of the front side surface of the lower die extends downward to form an arc-shaped guide portion; after the raw material enters from the feed port, it enters the extrusion channel after being buffered by the primary buffer chamber, and then is uniformly extruded after being buffered by the secondary buffer chamber, and flows evenly down along the front side surface of the lower die, and drips evenly through the arc-shaped guide portion to be coated on the substrate on the surface of the roller.
[0005] Preferably, the depth and width of the primary buffer chamber are greater than the depth and width of the secondary buffer chamber.
[0006] Preferably, the feed port is located in the middle of the rear side of the lower mold.
[0007] Preferably, a middle die is arranged between the upper die and the lower die, and the above three are locked as a whole by locking screws, the bottom surface of the middle die corresponds to the bottom surface of the upper die, the top surface of the middle die and the top surface of the lower die are provided with an extrusion channel, a primary buffer chamber, and a secondary buffer chamber at positions corresponding to the top surface of the lower die, the middle die is provided with a feed port and a feed channel corresponding to the lower die, the bottom surface of the middle die and the front top surface of the lower die form a first layer of extrusion channel, the upper die and the front top surface of the middle die form a second layer of extrusion channel, and the lower die and the front top surface of the middle die are provided with arc guide areas.
[0008] Preferably, n middle dies stacked from bottom to top are arranged between the upper die and the lower die, 10≥n≥2, the above-mentioned die heads are locked as one by locking screws, the bottom surface of the middle die corresponds to the bottom surface of the upper die, the top surface of the middle die and the top surface of the lower die are provided with an extrusion channel, a primary buffer chamber, and a secondary buffer chamber at positions corresponding to the middle die, the middle die is provided with a feed port and a feed channel corresponding to the lower die, the bottom surface of the lowermost middle die and the front top surface of the lower die form a first layer of extrusion channel, an extrusion channel is formed between the upper and lower adjacent middle dies, the upper die and the front top surface of the nth middle die form the n+1th layer of extrusion channel, and the lower die and the front top surfaces of all the middle dies are provided with arc guide areas.
[0009] The present invention controls the raw materials to be uniformly extruded in different width directions after passing through the two-stage buffer chamber, the die head does not contact the substrate, and the materials slide to the surface of the substrate by their own gravity after being extruded, forming a uniform and dense coating on the surface of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 It is a schematic diagram of the first structure of the present invention; Figure 2 for Figure 1 Exploded diagram of Figure 3 for Figure 1 Schematic diagram of the internal cross-sectional structure; Figure 4 It is a second structural schematic diagram of the present invention; Figure 5 for Figure 4 Exploded diagram of Figure 6 for Figure 4 Schematic diagram of the internal cross-sectional structure; Among them: 1—upper die; 2—lower die; 21—feed port; 22—primary buffer chamber; 23—feed channel; 24—extrusion channel; 25—secondary buffer chamber; 26—arc guide; 3—locking screw; 4—left side plate assembly; 5—right side plate assembly; 6—roller; 7—middle die; 8—arc guide area. DETAILED DESCRIPTION
[0011] The present invention will be further described in detail below in conjunction with the accompanying drawings.
[0012] like Figures 1 to 3 As shown, the present invention provides a curtain coating die head, comprising an upper die 1 and a lower die 2 with their front ends tilted upward, the upper die 1 and the lower die 2 are connected as a whole at the rear by a locking screw 3, the left and right sides of the upper die 1 and the lower die 2 are respectively provided with a left plate assembly 4 and a right plate assembly 5, the rear side of the lower die 2 is provided with a feed port 21, the middle area of the top surface of the lower die 2 is provided with a primary buffer chamber 22 along the width direction, the bottom surface of the primary buffer chamber 22 is connected to the feed port 21 through a feed channel 23, and the primary An extrusion channel 24 is provided on the top surface of the lower mold 2 on the front side of the buffer chamber 22. The top surface of the lower mold 2 is located on the front side of the primary buffer chamber 22 and a secondary buffer chamber 25 is provided along the width direction. The bottom surface of the front side surface of the lower mold 2 extends downward to form an arc-shaped guide portion 26. After the raw material enters from the feed port 21, it is buffered by the primary buffer chamber 22 and then enters the extrusion channel 24. It is then buffered by the secondary buffer chamber 25 and then evenly extruded. It flows evenly down along the front side surface of the lower mold 2 and evenly drips onto the substrate on the surface of the roller 6 through the arc-shaped guide portion 26.
[0013] In the above solution, the depth and width of the primary buffer chamber 22 are greater than the depth and width of the secondary buffer chamber 25 .
[0014] In addition, the feed port 21 is located in the middle of the rear side surface of the lower mold 2.
[0015] Furthermore, a middle die 7 is arranged between the upper die 1 and the lower die 2, and the above three are locked as a whole by a locking screw 3. The bottom surface of the middle die 7 corresponds to the bottom surface of the upper die 1, and the top surface of the middle die 7 and the top surface of the lower die 2 are provided with an extrusion channel, a primary buffer chamber 22, and a secondary buffer chamber 25. The middle die 7 is provided with a feed port 21 and a feed channel 23 corresponding to the lower die 2. The bottom surface of the middle die 7 and the front top surface of the lower die 2 form a first layer of extrusion channel, and the upper die 1 and the front top surface of the middle die 7 form a second layer of extrusion channel. The lower die 2 and the front top surface of the middle die 7 are provided with an arc guide area 8.
[0016] In addition, n middle molds 7 are stacked from bottom to top between the upper mold 1 and the lower mold 2, 10≥n≥2, such as Figures 4 to 6As shown, here n=2, the above-mentioned die head is locked as a whole by a locking screw 3, the bottom surface of the middle die 7 corresponds to the bottom surface of the upper die 1, the top surface of the middle die 7 and the top surface of the lower die 2 are provided with an extrusion channel, a primary buffer chamber 22, and a secondary buffer chamber 25, the middle die 7 is provided with a feed port 21 and a feed channel 23 corresponding to the lower die 2, the bottom surface of the lower middle die 7 and the front top surface of the lower die 2 form a first layer of extrusion channel, and an extrusion channel is formed between the upper and lower adjacent middle dies 7, the upper die 1 and the front top surface of the nth middle die 7 form the n+1th layer of extrusion channel, and the lower die 2 and all the front top surfaces of the middle dies 7 are provided with an arc guide area 8.
[0017] After the middle die 7 is arranged between the upper die 1 and the lower die 2, raw materials are independently introduced into the lower die 2 and each middle die 7. These raw materials can be the same raw material or different raw materials. After being extruded from their respective extrusion channels, they flow downward evenly under the action of their own gravity to form a multi-layer structure stacked up and down. The number of stacked layers is determined by the number of middle dies 7. Finally, they flow out from the front side of the lower die 2 under the action of gravity and drip evenly on the substrate on the surface of the roller 6 for coating. The dripping speed and the speed of the roller 6 are adjusted and controlled according to actual needs.
[0018] The above description is only a preferred embodiment of the present invention and does not impose any form of limitation on the invention. Any simple modification, equivalent change or modification made to the above embodiments based on the technical principle of the present invention still falls within the scope of the technical solution of the present invention.
Claims
1. A curtain coating die head, characterized in that: The invention comprises an upper die (1) and a lower die (2) with their front ends tilted upwards, the upper die (1) and the lower die (2) being connected as a whole at the rear by a locking screw (3), the left and right sides of the upper die (1) and the lower die (2) being respectively provided with a left plate assembly (4) and a right plate assembly (5), the rear side of the lower die (2) being provided with a feed port (21), the middle area of the top surface of the lower die (2) being provided with a primary buffer chamber (22) along the width direction, the bottom surface of the primary buffer chamber (22) being connected to the feed port (21) via a feed channel (23), the primary buffer chamber (22) An extrusion channel (24) is provided on the top surface of the front lower die (2); a secondary buffer chamber (25) is provided on the top surface of the lower die (2) in front of the primary buffer chamber (22) along the width direction; the bottom surface of the front side surface of the lower die (2) extends downward to form an arc-shaped guide portion (26); after the raw material enters from the feed port (21), it is buffered by the primary buffer chamber (22) and then enters the extrusion channel (24); after being buffered by the secondary buffer chamber (25), it is uniformly extruded and flows uniformly down along the front side surface of the lower die (2) and uniformly drips and is coated on the substrate on the surface of the roller (6).
2. A curtain coating die according to claim 1, characterized in that: The depth and width of the primary buffer chamber (22) are both greater than the depth and width of the secondary buffer chamber (25).
3. A curtain coating die according to claim 1, characterized in that: The feed port (21) is located in the middle of the rear side surface of the lower mold (2).
4. A curtain coating die according to claim 1, characterized in that: A middle mold (7) is arranged between the upper mold (1) and the lower mold (2), and the three are locked together by a locking screw (3). The bottom surface of the middle mold (7) corresponds to the bottom surface of the upper mold (1), and the top surface of the middle mold (7) and the top surface of the lower mold (2) are provided with an extrusion channel, a primary buffer chamber (22), and a secondary buffer chamber (25). The middle mold (7) is provided with a feed port (21) and a feed channel (23) corresponding to the lower mold (2). The bottom surface of the middle mold (7) and the front top surface of the lower mold (2) form a first layer of extrusion channel, and the upper mold (1) and the front top surface of the middle mold (7) form a second layer of extrusion channel. The front top surfaces of the lower mold (2) and the middle mold (7) are provided with arc guide areas (8).
5. A curtain coating die according to claim 1, characterized in that: Between the upper die (1) and the lower die (2), n middle dies (7) are stacked from bottom to top, 10≥n≥2. The die heads are locked together by a locking screw (3). The bottom surface of the middle die (7) corresponds to the bottom surface of the upper die (1). The top surface of the middle die (7) corresponds to the top surface of the lower die (2) and is provided with an extrusion channel, a primary buffer chamber (22), and a secondary buffer chamber (25). The middle die (7) is provided with a feed port (21) and a feed channel (23) corresponding to the lower die (2). The bottom surface of the lowest middle die (7) and the front top surface of the lower die (2) form a first layer of extrusion channels. Extrusion channels are formed between the upper and lower adjacent middle dies (7). The upper die (1) and the front top surface of the nth middle die (7) form an n+1th layer of extrusion channels. The front top surfaces of the lower die (2) and all the middle dies (7) are provided with arc guide areas (8).