Resin extrusion coating equipment

Abstract

The invention relates to the field of film resin coating, and discloses resin extrusion coating equipment which comprises a resin coating assembly and a trimming unit, the resin coating assembly comprises a shell, and a first cavity, a second cavity and a third cavity are formed in the shell; the first adjusting part, the second adjusting part and the third adjusting part are slidably arranged in the first cavity, the second cavity and the third cavity correspondingly, and the trimming unit is used for trimming the film base material. The adjusting position of the resin flow speed is replaced by die head volume adjustment from traditional auger rotation speed adjustment, so that the adjusting position is closer to the coating lip, the hysteresis of adjustment is reduced, and the adjusting cost is reduced.

Description

Technical Field

[0001] The invention relates to the field of film resin coating, in particular to resin extrusion coating equipment. Background Art

[0002] In the production process of film resin, film is usually used as the substrate. The substrate moves at a constant speed on the frame, and the resin is coated on the substrate through an extruder.

[0003] In the existing film resin production process, the resin particles are converted into a molten state in the extruder, extruded to the coating lip through the auger, and then coated on the uniformly moving substrate through the coating lip.

[0004] However, a common problem in the current production process is that the resin coating thickness is difficult to accurately control, resulting in unstable product quality and affecting production efficiency and economic benefits.

[0005] There are the following problems with controlling the resin flow rate through the auger:

[0006] Low control accuracy: The auger speed control is not precise enough, making it difficult to achieve accurate control of the resin flow rate.

[0007] Response lag: It takes a certain amount of time for changes in auger speed to be reflected in the resin flow rate, resulting in a response lag.

[0008] Impact of viscosity change: Changes in the viscosity of the resin will cause changes in the actual extrusion volume of the auger, affecting the coating thickness.

[0009] Mechanical wear: Long-term use will cause mechanical wear of the auger, affecting its accuracy and stability.

[0010] Due to the existence of the above problems, it is difficult to achieve accurate control of coating thickness in the existing thin film resin production process, resulting in unstable product quality and affecting production efficiency and economic benefits. Therefore, a new thin film resin coating thickness control device and method is urgently needed to solve the defects in the existing technology. Summary of the invention

[0011] The present invention is intended to provide a resin extrusion coating device to simplify the control method of the resin coating thickness, thereby improving the quality of the film resin product.

[0012] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: resin extrusion coating equipment, including a resin coating component and a trimming unit, the resin coating component includes a die head, the die head includes a shell, a first adjusting member, a second adjusting member and a third adjusting member, a first chamber, a second chamber and a third chamber are arranged in the shell, and a coating lip is arranged on the side of the shell away from the first chamber; the first chamber is connected to the extruder; the second chamber is arranged between the first chamber and the third chamber, and is respectively connected to the first chamber and the third chamber; the third chamber is connected to the coating lip, the first adjusting member, the second adjusting member and the third adjusting member are respectively slidably arranged in the first chamber, the second chamber and the third chamber, and the trimming unit is used to trim the film substrate.

[0013] The principle of the present invention is: the present invention adjusts the volumes of the first chamber and the second chamber respectively through the first adjusting member and the second adjusting member, thereby adjusting the outflow speed of the coating lip resin, and then controlling the resin coating thickness. The adjustment principle is as follows:

[0014] When the volume of the first cavity decreases:

[0015] Pressure increase: The volume of the first cavity decreases, resulting in an increase in pressure, and the speed at which the resin passes through the first cavity into the second cavity increases.

[0016] Increased flow rate: The pressure in the second cavity increases, and the speed at which the resin passes through the second cavity into the third cavity increases, resulting in an increase in the pressure at the coating lip outlet and a decrease in coating thickness.

[0017] When the volume of the second cavity decreases:

[0018] Pressure increase: The reduction in the volume of the second cavity causes the pressure to increase, and the speed at which the resin passes through the second cavity into the third cavity increases.

[0019] Flow rate slows down: Although the pressure in the third cavity increases, since the volume of the third cavity remains unchanged, the speed at which the resin passes through the coating lip slows down, resulting in a thicker coating thickness.

[0020] The beneficial effects of this solution are as follows: compared with the past, the coating thickness needs to be adjusted by adjusting the speed of the extruder auger and the heating temperature of the extruder. During the adjustment process, the auger speed, the temperature of the melt, the solidification speed of the melt and the movement speed of the film substrate need to be considered, and a multi-faceted coordination and balance are required to meet the selection of coating thickness. At the same time, due to the high viscosity of the resin, the auger adjustment has a certain hysteresis, and the adjustment is more difficult, requiring a lot of time, manpower and energy costs. Once the extruder is worn, it needs to be repeatedly invested. This solution simplifies the difficulty of adjusting the coating thickness through the special design of the die head, so that the speed of the resin passing through the coating lip can be adjusted by adjusting the first cavity and the second cavity of the die head. At the same time, since the adjustment position is relatively close to the coating lip, the hysteresis is relatively small, and the adjustment cost is lower.

[0021] Furthermore, a connecting throat is provided between the first chamber and the second chamber. The connecting throat is designed to be small in the middle and large at both ends to reduce the time that the resin remains in the first cavity or the second cavity, to prevent the resin from sticking or even solidifying on the inner wall of the die due to loss of temperature, affecting the outflow speed of the resin and thus affecting the uniformity of the resin coating.

[0022] Furthermore, the lower parts of the cross sections of the first cavity and the second cavity are both contracted toward the connecting throat. With the contracted connecting throat, after the resin enters the die head, it fills the first cavity, the second cavity, and the third cavity in sequence under the action of the viscosity of the resin itself, and the resin flows out in a waterfall-like manner through the connecting throat under the push of the subsequent resin, avoiding the phenomenon that the resin becomes thicker as it approaches the feed pipe during the outflow process, so that the resin coating is more uniform.

[0023] Furthermore, the resin coating assembly also includes a coating roller, which has a built-in heat exchange pipe in which a cooling medium circulates. The coating roller is rotatably arranged below the die head and a gap is reserved between the coating lip and the film substrate passes through the gap and fits the coating roller.

[0024] Further, the temperature range of the cooling medium is 15-20°C.

[0025] Beneficial effect: Generally speaking, the temperature of molten resin is 230℃. Plastic film is easy to deform at high temperature. The cooling medium can keep the substrate at a relatively low temperature and cool the resin at the same time, thus preventing the film from deforming at high temperature.

[0026] Furthermore, the first adjusting member, the second adjusting member and the third adjusting member each include an adjusting member body and a telescopic driving member, the adjusting member body is slidably arranged inside the shell, the telescopic driving member is threadedly connected to the shell, and the output shaft of the telescopic driving member is fixedly connected to the adjusting member body.

[0027] Beneficial effects: The telescopic parts can be adjusted quickly and conveniently.

[0028] Furthermore, the first adjusting member, the second adjusting member and the third adjusting member each include an adjusting member body and a screw rod, the adjusting member body is slidably arranged inside the shell, the screw rod is threadedly connected to the shell, and one end of the screw rod is rotatably connected to the adjusting member body.

[0029] Beneficial effect: The screw rod is self-locking and remains stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of an embodiment of the present invention;

[0031] Figure 2 Three-dimensional diagram of the die head of the embodiment of the present invention

[0032] Figure 3 An exploded view of a die head according to an embodiment of the present invention;

[0033] Figure 4 Schematic diagram of the internal structure of the die head according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The following is further described in detail through specific implementation methods:

[0035] The figure marks in the drawings of the specification include: die head 1, shell body 11, first end cover 13, first blocking member 131, second blocking member 132, third blocking member 133, second end cover 14, first fastener 121, second fastener 122, first adjusting member 151, adjusting member body 1501, driving rod 1502, second adjusting member 152, third adjusting member 153, first chamber 161, second chamber 162, third chamber 163, connecting throat 164, coating roller 21, tensioning roller 22, extruder 23, discharge pipe 231.

[0036] Example

[0037] The embodiment is basically as shown in the attached Figure 1-4 As shown, Figure 1-4 The resin extrusion coating equipment shown, such as Figure 1 As shown, when the film is coated with resin, the film is stretched on the frame by a tensioning mechanism, the tensioning mechanism includes a discharge roller, a receiving roller and a plurality of tensioning rollers 22, the discharge roller, the receiving roller and the tensioning roller 22 are all rotatably arranged on the frame, the discharge roller is fixed with a film, the film is stretched between the discharge roller and the receiving roller, and is tightened by the tensioning roller 22 to form a film substrate, the resin extrusion coating equipment is arranged between the discharge roller and the receiving roller, and is used to coat the film substrate with resin, including a discharge unit and a coating unit, the discharge unit includes an extruder 23 and a discharge auger, and the coating unit includes a die head 1 and a coating roller 21.

[0038] The extruder 23 can be an extrusion molding machine for plastic production disclosed in publication number CN117048016B, including an outer shell, an outer auger, an inner auger, a feed pipe, a resistance wire, a rotating ring and a detection component; a feed inlet and a feed outlet are provided on the outer shell, the inner auger and the outer auger are both arranged in the outer shell, the outer shell is bolted to the frame, the inner auger and the outer auger can rotate synchronously, the feed pipe is mounted on the outside of the inner auger, the feed pipe and the feed outlet are fixedly connected, and the resistance wire is arranged between the feed pipe and the outer auger, which will not be elaborated here.

[0039] The discharge auger is provided with a feed pipe and a discharge pipe 231, the feed pipe is connected with the discharge port, and the discharge pipe 231 is connected with the die head 1. When in use, the resin particles enter the extruder 23 from the feed port, and are transformed into a molten body under the action of the inner auger, the outer auger and the resistance wire. The molten body reaches the discharge port through the feed channel under the push of the inner auger, and flows into the discharge auger through the feed pipe, and flows into the die head 1 through the discharge pipe 231.

[0040] like Figure 2 , Figure 3 As shown, the die head 1 includes a shell body 11, a first end cover 13, a second end cover 14, a first fastener 121 and a second fastener 122. The first end cover 13 is welded or threaded with a first blocking member 131, a second blocking member 132 and a third blocking member 133, preferably threaded, and the first blocking member 131, the second blocking member 132 and the third blocking member 133 are adapted to the inner wall of the shell body 11. The second end cover 14 is slidably provided with a first adjusting member 151 and a second adjusting member 152. The structures of the first adjusting member 151, the second adjusting member 152 and the third adjusting member 153 are basically the same, and all include an adjusting member body 1501 and a driving rod 1502. The driving rod 1502 is welded to the adjusting member body 1501, and the adjusting member body 1501 is slidably arranged inside the shell. The driving rod 1502 is slidably connected to the second end cover 14, and the free end of the driving rod 1502 is connected to a telescopic driving member, and the output shaft of the telescopic driving member is welded to the driving rod 1502.

[0041] Reference Figure 2 , Figure 4 As shown, the shell body 11 respectively forms the first chamber 161, the second chamber 162 and the third chamber 163 with the first sealing member 131 and the first adjusting member 151, the second sealing member 132 and the second adjusting member 152, and the third sealing member 133 and the third adjusting member 153. The second chamber 162 is provided with a connecting throat 164, and the first chamber 161 is connected with the discharge pipe 231; the second chamber 162 is arranged between the first chamber 161 and the third chamber 163, and is respectively connected with the first chamber 161 and the third chamber 163 through the connecting throat 164; the third chamber 163 is provided with a coating lip away from the second chamber 162, and the coating lip is connected with the atmosphere.

[0042] During assembly, first adhere the first blocking piece 131, the second blocking piece 132 and the third blocking piece 133 to the first end cover 13, and extend the first blocking piece 131, the second blocking piece 132 and the third blocking piece 133 into the shell body 11, and at the same time put the first adjusting piece 151, the second adjusting piece 152 and the third adjusting piece 153 into the shell body 11, then fix the shell body 11 to the first fastener 121 and the second fastener 122 by bolts, finally, pass the driving rod 1502 through the second end cover 14, fix the first end cover 13 and the second end cover 14 to the second fastener 122 by bolts, and complete the assembly of the die head 1.

[0043] The structures of the first chamber 161, the second chamber 162 and the third chamber 163 are substantially the same. The volumes of the first chamber 161 and the second chamber 162 are adjusted by adjusting the relative positions of the first adjusting member 151 and the second adjusting member 152 and the shell body 11. Meanwhile, the coating width of the coating lip is determined by the relative position of the third adjusting member 153 and the shell body 11. The resin melt flows through the first chamber 161, the second chamber 162 and the third chamber 163 in sequence, and flows out through the coating lip to be coated on the surface of the film substrate.

[0044] like Figure 3 As shown, a connecting throat 164 is provided between the first chamber 161 and the second chamber 162 and between the second chamber 162 and the third chamber 163. The connecting throat 164 is designed to be small in the middle and large at both ends. The lower parts of the cross sections of the first chamber 161 and the second chamber 162 both shrink toward the connecting throat 164. With the help of the special setting of the connecting throat 164, the molten body can fill the first chamber 161, the second chamber 162 and the third chamber 163 in turn, and then by adjusting the volume of the first chamber 161 and the second chamber 162, the flow rate of the molten body flowing out of the coating lip is adjusted, and finally the thickness of the resin coating is adjusted.

[0045] The resin coating assembly also includes a coating roller 21, which has a heat exchange pipe built in it. A cooling medium circulates in the heat exchange pipe. The coating roller 21 is rotatably arranged below the die head 1 and a gap is reserved between the coating lip. The film substrate passes through the gap and fits the coating roller 21. The temperature range of the cooling medium is 15-20°C, so that the resin melt coated on the film substrate is cooled by the heat transfer of the cooling medium to prevent the high-temperature resin melt from damaging the film substrate.

[0046] Example 2

[0047] Embodiment 2 is basically the same as Embodiment 1, except that:

[0048] The driving rod 1502 is a screw rod, which is threadedly connected to the second end cover 14. One end of the screw rod is rotatably connected to the adjusting member body 1501. The volumes of the first chamber 161, the second chamber 162 and the third chamber 163 are adjusted by screwing the screw rod in and out on the second end cover 14. The self-locking property of the screw rod is used to prevent the adjusting member body 1501 from sliding during the coating process, thereby affecting the outflow speed of the resin and thus affecting the coating thickness.

[0049] The above is only an embodiment of the present invention, and common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that the technical means for solving the problems in the above-mentioned embodiments of the present invention can be used in combination to solve multiple technical problems at the same time. For those skilled in the art, several modifications and improvements can be made without departing from the technical solution of the present invention, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. Resin extrusion coating equipment, used for coating resin on film substrate, characterized in that: It includes an extruder and a resin coating component, the extruder includes a discharge port, the discharge port is provided with an auger, the resin coating component includes a die head, the die head includes a shell, a first adjusting member, a second adjusting member and a third adjusting member, the shell is provided with a first chamber, a second chamber and a third chamber, and a coating lip is provided on the shell away from the first chamber side; the first chamber is connected with the discharge port; the second chamber is provided between the first chamber and the third chamber, and is respectively connected with the first chamber and the third chamber; the third chamber is connected with the coating lip, and the first adjusting member, the second adjusting member and the third adjusting member are respectively slidably provided in the first chamber, the second chamber and the third chamber.

2. The resin extrusion coating equipment according to claim 1, characterized in that: A connecting throat is provided between the first chamber and the second chamber, and the connecting throat is designed to be small in the middle and large at both ends.

3. The resin extrusion coating equipment according to claim 2, characterized in that: The lower portions of the cross sections of the first chamber and the second chamber both contract toward the connecting throat.

4. The resin extrusion coating equipment according to claim 3, characterized in that: The resin coating assembly also includes a coating roller, which has a built-in heat exchange pipe in which a cooling medium circulates. The coating roller is rotatably arranged below the die head and a gap is reserved between the coating lip. The film substrate passes through the gap and fits the coating roller.

5. The resin extrusion coating equipment according to claim 4, characterized in that: The temperature range of the cooling medium is 15-20°C.

6. The resin extrusion coating equipment according to claim 5, characterized in that: The first adjusting member, the second adjusting member and the third adjusting member each include an adjusting member body and a telescopic driving member. The adjusting member body is slidably arranged inside the shell, the telescopic driving member is threadedly connected to the shell, and the output shaft of the telescopic driving member is fixedly connected to the adjusting member body.

7. The resin extrusion coating equipment according to claim 5, characterized in that: The first adjusting member, the second adjusting member and the third adjusting member all include an adjusting member body and a screw rod. The adjusting member body is slidably arranged inside the shell, the screw rod is threadedly connected to the shell, and one end of the screw rod is rotatably connected to the adjusting member body.

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