CN119608494A - Curtain type coating die head - Google Patents

Abstract

The present invention provides a curtain coating die head, comprising an upper die and a lower die with the front end tilted upward, the upper die and the lower die are connected as a whole by a locking screw at the rear, 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 at 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 a secondary buffer chamber is provided along the width direction, and the bottom surface of the front side of the lower die extends downward to form an arc-shaped guide portion. The die head of the present invention does not contact the substrate, and the material slides to the surface of the substrate by its own gravity after extrusion, forming a uniform and dense coating on the surface of the substrate.

Description

Curtain type coating die head

Technical Field

The invention relates to the technical field of coating dies, in particular to a curtain coating die.

Background

In comparison to standard hot melt adhesive coated dies in which the die is in direct contact with the substrate during coating, for substrates of elastomeric substrate elastomeric materials such as PU, TPU films, stretch fabrics, etc., the die and substrate contact affects the tension balance of the substrate. For porous substrates and rough surface substrates, such as spunlaced fabrics of medical tapes, flannelette of harness tapes, textile fabrics, kraft paper of kraft paper tapes, sandpaper and the like, die lip wear can occur when the die contacts the substrate. It is therefore desirable to design a die that is non-contact with the substrate.

Disclosure of Invention

In view of the above problems, the present invention aims to provide a curtain coating die, which is free from contact with a substrate, and after the extrusion of a material, the material slides down to the surface of the substrate by self gravity, so that a uniform and compact coating is formed on the surface of the substrate.

The curtain coating die head is characterized by comprising an upper die and a lower die, wherein the front ends of the upper die and the lower die are obliquely arranged upwards, the rear parts of the upper die and the lower die are connected into a whole through die locking screws, left side plate assemblies and right side plate assemblies are respectively arranged on the left side surface and the right side surface of the upper die and the lower die, a feeding hole is formed in the rear side surface of the lower die, a first-stage buffer cavity is formed in the middle area of the top surface of the lower die along the width direction, the bottom surface of the first-stage buffer cavity is communicated with the feeding hole through a feeding channel, an extrusion channel is formed in the top surface of the lower die on the front side of the first-stage buffer cavity, a second-stage buffer cavity is formed in the front side of the lower die along the width direction, the bottom surface of the front side surface of the lower die extends downwards to form an arc-shaped guide part, raw materials enter the extrusion channel after being buffered by the first-stage buffer cavity, are evenly extruded through the second-stage buffer cavity, and evenly flow down along the front side surface of the lower die and evenly drop-coated on a substrate on the surface of a roller through the arc-shaped guide part.

Preferably, the depth and width of the primary buffer chamber are greater than the depth and width of the secondary buffer chamber.

Preferably, the feeding hole is positioned in the middle of the rear side surface of the lower die.

Preferably, a middle die is arranged between the upper die and the lower die, the upper die and the lower die are locked into a whole through a die locking screw, the bottom surface of the middle die corresponds to the bottom surface of the upper die, an extrusion channel, a primary buffer chamber and a secondary buffer chamber are arranged at positions of the top surface of the middle die corresponding to the top surface of the lower die, the middle die is provided with a feed inlet and a feed channel corresponding to the lower die, a first layer extrusion channel is formed between the bottom surface of the middle die and the top surface of the front part of the lower die, a second layer extrusion channel is formed between the upper die and the top surface of the front part of the middle die, and circular arc guide areas are arranged on the top surfaces of the front sides of the lower die and the middle die.

Preferably, n middle molds stacked from bottom to top are arranged between the upper mold and the lower mold, n is more than or equal to 10 and more than or equal to 2, the dies are locked into a whole through mold locking screws, the bottom surfaces of the middle molds correspond to the bottom surfaces of the upper mold, extrusion channels, primary buffer chambers and secondary buffer chambers are arranged at positions corresponding to the top surfaces of the lower molds, feeding inlets and feeding channels corresponding to the lower molds are arranged at the middle molds, a first layer of extrusion channel is formed between the bottom surface of the middle mold at the lowest end and the top surface of the front part of the lower mold, an extrusion channel is formed between the upper adjacent middle mold and the lower adjacent middle mold, an n+1 layer of extrusion channel is formed between the top surfaces of the front parts of the upper mold and the n middle molds, and circular arc guide areas are arranged on the top surfaces of the front sides of the lower mold and all the middle molds.

According to the invention, after passing through the two-stage buffer chambers, the raw materials are controlled to be extruded uniformly in different breadth directions, the die head is not contacted with the substrate, the extruded raw materials slide to the surface of the substrate through self gravity, and a uniform and compact coating is formed on the surface of the substrate.

Drawings

FIG. 1 is a schematic view of a first construction of the present invention;

FIG. 2 is an exploded view of FIG. 1;

FIG. 3 is a schematic view of the internal cross-sectional structure of FIG. 1;

FIG. 4 is a second schematic diagram of the present invention;

FIG. 5 is an exploded view of FIG. 4;

FIG. 6 is a schematic view of the internal cross-sectional structure of FIG. 4;

Wherein 1-upper die; 2-lower die, 21-feed inlet, 22-first-stage buffer chamber, 23-feed channel, 24-extrusion channel, 25-second-stage buffer chamber, 26-arc guide part, 3-die locking screw, 4-left side plate assembly, 5-right side plate assembly, 6-roller, 7-middle die and 8-arc guide area.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1 to 3, the invention provides a curtain coating die head, which comprises an upper die 1 and a lower die 2, wherein the front ends of the upper die 1 and the lower die 2 are obliquely arranged upwards, the rear parts of the upper die 1 and the lower die 2 are connected into a whole through a die locking screw 3, left side plate assemblies 4 and right side plate assemblies 5 are respectively arranged on the left side surface and the right side surface of the upper die 1 and the lower die 2, a feed inlet 21 is arranged on the rear side surface of the lower die 2, a primary buffer chamber 22 is arranged in the middle area of the top surface of the lower die 2 along the width direction, the bottom surface of the primary buffer chamber 22 is communicated with the feed inlet 21 through a feed channel 23, an extrusion channel 24 is arranged on the top surface of the lower die 2 at the front side of the primary buffer chamber 22, a secondary buffer chamber 25 is arranged on the top surface of the lower die 2 along the width direction, the bottom surface of the front side surface of the lower die 2 extends downwards to form an arc-shaped guide part 26, raw materials enter the primary buffer chamber 22 from the feed inlet 21, enter the extrusion channel 24, are uniformly extruded through the secondary buffer chamber 25, uniformly flow down along the secondary buffer chamber 25, and uniformly drop down on the arc-shaped coating roller surface 6 through the front surface of the guide part 26.

In the above-described embodiment, the depth and width of the primary buffer chamber 22 are greater than the depth and width of the secondary buffer chamber 25.

In addition, the feed port 21 is positioned in the middle of the rear side surface of the lower die 2.

Further, a middle die 7 is arranged between the upper die 1 and the lower die 2, the upper die 1 and the lower die 2 are locked into a whole through a die locking screw 3, the bottom surface of the middle die 7 corresponds to the bottom surface of the upper die 1, extrusion channels, a primary buffer chamber 22 and a secondary buffer chamber 25 are arranged at positions corresponding to the top surfaces of the middle die 7 and the lower die 2, the middle die 7 is provided with a feed inlet 21 and a feed channel 23 corresponding to the lower die 2, a first layer extrusion channel is formed between the bottom surface of the middle die 7 and the top surface of the front part of the lower die 2, a second layer extrusion channel is formed between the upper die 1 and the top surface of the front part of the middle die 7, and an arc guide area 8 is arranged on the top surfaces of the front sides of the lower die 2 and the middle die 7.

In addition, n middle dies 7,10 is greater than or equal to n and is greater than or equal to 2 stacked from bottom to top are arranged between the upper die 1 and the lower die 2, n=2 is shown in fig. 4 to 6, the dies are locked into a whole through die locking screws 3, the bottom surface of each middle die 7 corresponds to the bottom surface of the upper die 1, extrusion channels, a primary buffer chamber 22 and a secondary buffer chamber 25 are arranged at positions, corresponding to the top surface of the lower die 2, of the top surface of each middle die 7, a feed inlet 21 and a feed channel 23 are arranged corresponding to the lower die 2, a first layer extrusion channel is formed between the bottom surface of the middle die 7 at the lowest end and the top surface of the front part of the lower die 2, an extrusion channel is formed between the upper die 1 and the top surface of the front part of the n-th middle die 7, n+1 layer extrusion channels are formed between the upper die 2 and the top surfaces of the front sides of all middle dies 7, and circular arc guide areas 8 are arranged on the top surfaces of the front sides of the lower die 2 and all the middle dies 7.

After the middle die 7 is arranged between the upper die 1 and the lower die 2, the lower die 2 and each middle die 7 independently enter raw materials, the raw materials can be the same raw materials or different raw materials, the raw materials are extruded from respective extrusion channels and then uniformly flow downwards under the action of self gravity to form a vertically overlapped multi-layer structure, the overlapped layers are determined by the number of the middle dies 7, finally flow out from the front side surface of the lower die 2 under the action of gravity, uniformly drop on a substrate on the surface of the roller 6 for coating, and the dropping speed and the speed of the roller 6 are regulated and controlled according to actual needs.

The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the invention in any way, but any simple modification, equivalent variation or modification made to the above embodiments according to the technical principles of the present invention still falls within the scope of the technical solutions of the present invention.

Claims (5)

1. A curtain coating die head, characterized in that: it comprises an upper die (1) and a lower die (2) with the front end 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 die (2) at the front side of the buffer chamber (22); a secondary buffer chamber (25) is provided on the top surface of the lower die (2) in the front side 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), and then is evenly extruded after being buffered by the secondary buffer chamber (25), and flows evenly down along the front side surface of the lower die (2) and evenly 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 greater than the depth and width of the secondary buffer chamber (25). 3. A curtain coating die head according to claim 1, characterized in that: the feed port (21) is located in the middle of the rear side of the lower die (2). 4. A curtain coating die according to claim 1, characterized in that: a middle die (7) is arranged between the upper die (1) and the lower die (2), and the three 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) 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; the upper die (1) and the front top surface of the middle die (7) form a second layer of extrusion channel; the front top surfaces of the lower die (2) and the middle die (7) are provided with arc guide areas (8). 5. A curtain coating die head according to claim 1, characterized in that: n middle dies (7) stacked from bottom to top are arranged between the upper die (1) and the lower die (2), 10≥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), and the top surface of the middle die (7) is provided with an extrusion channel, a primary buffer chamber (22), and a secondary buffer chamber (23) at a position corresponding to the top surface of the lower die (2). The cavity (25) is provided with a feed port (21) and a feed channel (23) corresponding to the lower die (2); the bottom surface of the lowermost middle die (7) and the front top surface of the lower die (2) form a first layer of extrusion channel; 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 an n+1th layer of extrusion channel; the front top surfaces of the lower die (2) and all the middle dies (7) are provided with an arc guide area (8).