Slot die coater capable of automatically adjusting the position of a shim plate and method for adjusting the position of the shim plate of a slot die coater

Abstract

The present invention relates to a slot die coater capable of automatically adjusting the position of a shim plate, including a slot die, at least one motor disposed inside the slot die, a shim plate disposed on the slot die, and at least one pin that penetrates the shim plate and is connected to the motor and is movable by the motor.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0102619 filed on August 17, 2022, and includes all the contents disclosed in the document of the Korean patent application as part of this specification.

[0002] The present invention relates to a slot die coater capable of adjusting the position of a shim plate and a method for adjusting the position of the shim plate of a slot die coater. More specifically, the present invention relates to a slot die coater capable of automatically adjusting the position of a shim plate based on information measured by a vision system and a method for automatically adjusting the position of the shim plate.

Background Art

[0003] Recently, as energy prices have risen due to the depletion of fossil fuels and environmental pollution has become more serious, the demand for environmentally friendly alternative energy sources has been increasing. Along with this, research on various power generation technologies such as nuclear power, wind power, tidal power, and solar power has been progressing, and interest in power storage devices for more efficiently using the generated energy has also been increasing.

[0004] In particular, with the development of mobile device technology and the increasing demand, the demand for batteries as an energy source has been rapidly increasing, and accordingly, research on secondary batteries that can meet various needs has been progressing.

[0005] A secondary battery may include a positive electrode, a negative electrode, and a separator. The positive electrode and the negative electrode may have a positive electrode active material and a negative electrode active material coated on the respective positive electrode current collector and negative electrode current collector. At this time, a slot die coater can be used to coat the positive electrode active material and the negative electrode active material.

[0006] The slot die coater can perform coating while keeping the coating widths of the positive electrode active material and the negative electrode active material constant. In order to keep the coating width constant, the shim plate of the slot die coater must be precisely adjusted within the slot die coater.

[0007] However, the conventional method in which a person directly manually adjusts the shim bracket to adjust the position of the shim plate has a limitation that it is difficult to precisely adjust the position of the shim plate, and since direct manual input is required to adjust the position of the shim plate, there are drawbacks such as time and labor costs being incurred.

[0008] Therefore, in order to overcome such limitations and drawbacks, research on a technology for automatically adjusting the position of the shim plate is being advanced.

Summary of the Invention

Problems to be Solved by the Invention

[0009] An object of the present invention is to provide a slot die coater capable of automatically adjusting the position of a shim plate.

[0010] An object of the present invention is to provide a method for automatically adjusting the position of a shim plate.

[0011] However, the problems to be solved by the present invention are not limited to the above content, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0012] In order to achieve the above object of the present invention, a slot die coater according to an embodiment of the present invention can include a slot die, at least one motor disposed within the slot die, a shim plate disposed on the slot die, and at least one pin that penetrates the shim plate and is connected to the motor and is movable by the motor.

[0013] In one embodiment, the pin may be movable in a first direction in which the coating liquid is applied and a second direction opposite to the first direction.

[0014] In one embodiment, the pin may be movable in a third direction which is the direction in which the pin penetrates the shim plate and a fourth direction opposite to the third direction.

[0015] In one embodiment, the pin may be movable in a fifth direction perpendicular to the first direction and the third direction and a sixth direction opposite to the fifth direction.

[0016] In one embodiment, when the distance between the end of the shim plate measured by the vision system and the end of the slot die exceeds a preset error range, the motor can adjust the position of the shim plate by moving the pin.

[0017] In one embodiment, there may be a plurality of the motors and the pins respectively.

[0018] To achieve the object of the present invention, a method for adjusting the position of a shim plate according to an embodiment of the present invention may include a step of measuring the distance between the end of a slot die and the end of a shim plate disposed on the slot die, a step of determining whether the distance is within a preset error range, and a step of adjusting the position of the shim plate according to the result of the determination.

[0019] In one embodiment, the step of adjusting the position of the shim plate may be performed by a pin that penetrates the shim plate and is connected to a motor disposed in the slot die.

[0020] In one embodiment, after the step of adjusting the position of the shim plate, the step of fixing the shim plate may further be included.

[0021] In one embodiment, the step of fixing the shim plate can be performed by a pin that penetrates the shim plate and is connected to a motor disposed within the slot die.

[0022] In one embodiment, after the step of adjusting the position of the shim plate, the method can further include the step of re-measuring the distance between the end of the shim plate and the end of the slot die.

[0023] In one embodiment, after the step of re-measuring, if the distance between the end of the shim plate and the end of the slot die exceeds the preset error range, the method can further include the step of generating an alarm.

Advantages of the Invention

[0024] According to the present invention, the position of the shim plate disposed on the slot die is automatically adjusted by a pin that penetrates the shim plate and is connected to the slot die. The pin is connected to a motor disposed within the slot die, and the motor can adjust the distance between the shim plate and the slot die by adjusting the position of the pin based on information measured by the vision system. Thereby, the present invention can uniformly apply the coating liquid onto the substrate. Further, since the position of the shim plate is automatically adjusted via the vision system and the motor, there is no need to add manual labor, and costs and time can be reduced, and the position of the shim plate can be finely adjusted via the motor and the pin.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Best Mode for Carrying Out the Invention

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and the claims should not be construed as being limited to the ordinary meaning or the dictionary meaning. The inventor should interpret them in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that the inventor can appropriately define the concept of the terms in order to explain his invention in the best way. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. It should be understood that there are various equivalents and modifications that can replace them at the time of this application.

[0027] The slot die coater of the present invention is a device that includes a slot and applies a coating liquid onto a substrate through the slot. The slot die coater can include a first slot die and a second slot die. The "substrate" described below is a current collector, and the coating liquid is an "electrode active material slurry". However, the scope of the rights of the present invention is not limited to these. For example, the substrate may be a porous support that constitutes a separator membrane, and the coating liquid may correspond to an organic substance. That is, in the case where thin film coating is required, the substrate and the coating liquid can be any kind.

[0028] In this specification, the first direction (DR1) is defined as the direction in which the coating liquid is discharged, the second direction (DR2) is defined as the direction opposite to the first direction (DR1), the third direction (DR3) and the fourth direction (DR4) are each defined as a direction perpendicular to the first direction (DR1) and the second direction (DR2), and the fifth direction (DR5) and the sixth direction (DR6) are each defined as a direction perpendicular to the first direction (DR1) and the third direction (DR3).

[0029] Figures 1a to 1c show a slot die coater according to an embodiment of the present invention. Referring to Figures 1a to 1c, a slot die coater (100) according to an embodiment of the present invention may include a first slot die (100a), a second slot die (100b), and a shim plate (100c). The slot die coater (100) can apply a coating liquid (220) onto a substrate (210). Thereby, the coating liquid (220) can be applied to the substrate (210). A coating roll (200) can convey the substrate (210). The coating roll (220) is disposed in front of the slot die coater (100), and the substrate (210) can be conveyed by the rotation of the coating roll (220). The coating liquid (220) discharged while the coating roll (220) runs the substrate (210) can be uniformly applied to the substrate (210). For this reason, the coating roll (220) must rotate at a constant speed. Also, the slot die coater (100) discharges the coating liquid (220) so as to have a certain spreading width and must discharge the coating liquid (220) at a constant speed.

[0030] Although not shown, at least one of the first slot die (100a) and the second slot die (100b) is provided with a storage space for storing the coating liquid (220), and the storage space can receive the supply of the coating liquid (220) through a passage connected from the outside.

[0031] The shim plate (100c) has an area cut open to provide an opening, and is disposed between a first slot die (100a) and a second slot die (100b) facing each other. The opening is disposed between a first die lip (110a) and a second die lip (110b). The shim plate (100c) preferably consists of a material with sealing properties in order to also function as a gasket that prevents the coating liquid (220) from leaking into the gap between the first slot die (100a) and the second slot die (100b) except in the area where the opening is formed.

[0032] The width of the coating liquid (220) to be coated may be determined by the width of the opening of the shim plate (100c). A plurality of such openings may exist, whereby a plurality of coating layers can be formed on the substrate (210) spaced apart from each other.

[0033] The coating result by the slot die coater (100) may be affected by various factors. As an example, the coating result may vary depending on the alignment degree between the first die lip (110a) corresponding to the end of the first slot die (100a) and the second die lip (110b) corresponding to the end of the second slot die (100b). Alternatively, the coating result may also vary depending on the distance between the first and second die lips (110a, 110b) and the shim end (110c) which is the end of the shim plate (100c).

[0034] If the distance between the first and second die lips (110a, 110b) and the shim end (110c) is too large, when the coating liquid (220) is applied, the spreading width of the coating liquid (220) becomes large, and the coating liquid (220) may not be uniformly applied on the substrate (210). Therefore, in order to adjust the distance between the first and second die lips (110a, 110b) and the shim end (110c), the slot die coater (100) can further include a motor and a pin. The motor can move or fix a pin connected to the motor to move the shim plate (100c). Such a motor and pin will be described with reference to the drawings described later.

[0035] FIG. 2 shows an embodiment of a shim plate included in the slot die coater of FIG. 1a. Referring to FIGS. 1a and 2, the shim plate (100c) can include two openings (OP1, OP2). The first opening (OP1) and the second opening (OP2) can be defined as spaces for discharging the coating liquid (220), respectively. That is, the coating liquid (220) stored in the slot die coater (100) can be discharged through each of the first opening (OP1) and the second opening (OP2). However, this is exemplary, and the shim plate (100c) can include at least one opening.

[0036] As described above, the coating result may vary depending on the distance between the shim end (110c) and the second die lip (110b). Therefore, the slot die coater (100) according to an embodiment of the present invention defines an error range for the distance between the shim end (110c) and the second die lip (110b), and can adjust the position of the shim plate (100c) so that the distance between the shim end (110c) and the second die lip (110b) is located within a preset error range. The position of the shim plate (100c) can be adjusted before the first slot die (100a) and the second slot die (100b) are coupled with the shim plate (100c) sandwiched therebetween.

[0037] Whether the distance between the shim end (110c) and the second die lip (110b) falls within the error range can be determined by various criteria. For example, after measuring the distance between the shim end (110c) and the second die lip (110b) at three locations, left, middle, and right, on a plane, it is possible to compare and determine whether the measured distances each fall within a preset error range. However, this is exemplary, and it is also possible to determine whether the distance between the shim end (110c) and the second die lip (110b) falls within a preset error range based only on two locations, left and right.

[0038] Each error range can be determined based on a target value and an adjusted completion value. The target value can be defined as the ideal distance between the shim end (110c) and the second die lip (110b). The ideal distance can mean the distance between the shim end (110c) and the second die lip (110b) for the coating liquid to be applied normally. For example, looking at the left side of the shim plate (100c) as a reference, the left-side distance (OFS_L), which is the shortest distance between the left-side portion of the shim end (110c) and the second die lip (110b), can have a target value of 500 μm. The target value can be determined considering various factors. For example, the target value can be determined based on result values of quality measurements such as coating width, mismatch, sliding, and fat edge.

[0039] The adjusted completion value of the left-side distance (OFS_L) can correspond to the maximum value of the difference between the target value for determining that the shim plate (100c) is in the desired position and the measured value of the vision system. For example, the adjusted completion value may be 80 μm, and when the left-side distance (OFS_L) measured by the vision system corresponds to 420 to 580 μm, it can be determined that the shim plate (100c) is in the desired position. That is, the error range for the left-side distance (OFS_L) can correspond to 420 to 580 μm.

[0040] The target value can be set within various ranges and can have a target upper limit value and a target lower limit value. For example, the target value can be 500 μm, the target upper limit value can be 900 μm, and the target lower limit value can be 100 μm.

[0041] The aforementioned target value and adjusted completion value are exemplary, and the target value and adjusted completion value can be determined with various numerical values. Also, the target upper limit value and target lower limit value can be determined with various numerical values.

[0042] In addition, although the description of the aforementioned values was based on the left distance (OFS_L), the description of the aforementioned values can be similarly applied to the right distance (OFS_R) and the middle distance (OFS_M).

[0043] However, when the difference between the maximum value and the minimum value among the left distance (OFS_L), the right distance (OFS_R), and the middle distance (OFS_M) becomes larger than a preset numerical value, the shim plate (100c) may warp, causing malfunctions and performance degradation of the slot die coater (100). Therefore, it is desirable that the difference between the maximum value and the minimum value among the left distance (OFS_L), the right distance (OFS_R), and the middle distance (OFS_M) be maintained below the preset numerical value, and the preset numerical value can be defined as a setting limit value. The setting limit value can be 120 μm. For example, when the difference between the left distance (OFS_L) and the right distance (OFS_R) exceeds 120 μm, the position of the shim plate (100c) can be readjusted. Since the setting limit value corresponds to the limit value at which the shim plate (100c) can be used without deformation, it may vary depending on the size and material of the shim plate (100c).

[0044] The first and second pins (300a, 300b) are movable in a first direction (DR1) and a second direction (DR2) opposite to the first direction (DR1) so that the distance between the shim end (110c) and the second die lip (110b) falls within a preset error range. Each of the first pin (300a) and the second pin (300b) may penetrate the shim plate (100c) and be connected to the second slot die (100b). The second slot die (100b) may be provided with a passage for the first pin (300a) and the second pin (300b) to move. Different from that shown in FIG. 2, one pin may be used to move the shim plate (100c), or three or more pins may be used. However, for the sake of convenience of explanation, the description will proceed based on an embodiment in which two pins (300a, 300b) are used to move the shim plate (100c).

[0045] FIGS. 3a through 3c show one embodiment of adjusting the position of the shim plate included in the slot die cutter of FIG. 1a.

[0046] Referring to FIG. 3a, the vision system (400) can measure the distance between the shim end (110c) and the second die lip (110b). The vision system (400) may be a camera. The distance measured by the vision system (400) can be managed through a control unit (not shown). When the measured distance is outside a preset error range, the second motor (500b) can move the second pin (300b). Here, the second motor (500b) can move the second pin (300b) in the first to sixth directions (DR1-DR6). Alternatively, the second motor (500b) may be composed of a plurality of sub-motors, and each motor can move the second pin (300b) by changing directions relative to each other. For example, the second motor (500b) includes first to third sub-motors. The first sub-motor can move the second pin (300b) in the first direction (DR1) and the second direction (DR2), the second sub-motor can move the second pin (300b) in the third direction (DR3) and the fourth direction (DR4), and the third sub-motor can move the second pin (300b) in the fifth direction (DR5) and the sixth direction (DR6).

[0047] At this time, the second motor (500b) can move the second pin (300b) in units of 100 μm. More preferably, the second motor (500b) can also move the second pin (300b) in units of 100 μm or less. For example, the second motor (500b) can also move the second pin (300b) in units of 50 μm or 10 μm. However, this is exemplary, and the second motor (200b) can also move the second pin (300b) in units of 100 μm or more. Thereby, the shim plate (100c) can also be moved in units of 100 μm, or more, or less than 100 μm.

[0048] Referring to FIGS. 3a and 3b, the shim plate (100c) can be moved in the first direction (DR1) by the second motor (500b) and the second adjustment pin (300b), whereby the distance between the shim end (110c) and the second die lip (110b) can fall within a preset error range.

[0049] After the position of the shim plate (100c) is adjusted by the second motor (500b) and the second adjustment pin (300b), it is possible to recheck whether the distance between the shim end (110c) and the second die lip (110b) falls within a preset error range. Even after the position of the shim plate (100c) is adjusted by the second motor (500b) and the second adjustment pin (300b), if the distance between the shim end (110c) and the second die lip (110b) falls outside the preset error range, an alarm can sound and the system can be inspected, or a person can manually adjust the distance between the shim end (110c) and the second die lip (110b) to be within the preset error range. However, the alarm can also be adjusted to sound after the position of the shim plate (100c) has been adjusted N or more times (N is a natural number of 2 or more). For example, it can be set so that the alarm sounds if the distance between the shim end (110c) and the second die lip (110b) falls outside the preset error range even after the position of the shim plate (100c) has been adjusted 5 times.

[0050] Referring to FIGS. 3b and 3c, when the vision system (400) confirms that the distance between the shim end (110c) and the second die lip (110b) has fallen within a preset error range, the second motor (500b) can move the second pin (300b) in the fourth direction (DR4) to fix the shim plate (100c).

[0051] When the fixing of the shim plate (100c) is completed, it can be combined so that the first slot die (100a), the shim plate (100c), and the second slot die (100b) are stacked in order, like the slot die cutter (100) of FIG. 1a.

[0052] Figures 4a and 4b show an embodiment of adjusting the position of the shim plate included in the slot die coater of FIG. 1a.

[0053] Referring to FIGS. 4a and 4b, when the vision system (400) confirms that the distance between the shim end (110c) and the second die lip (110b) is within a preset error range, the second motor (500b) does not move the second pin (300b) in the first direction (DR1) or the second direction (DR2), but can move it only in the fourth direction (DR4) to fix the shim plate (100c).

[0054] FIGS. 5a to 5c show an embodiment of adjusting the position of the shim plate included in the slot die coater of FIG. 1a. FIGS. 5a to 5c show an example in which the motor moves the pin in the fifth direction (DR5) and the sixth direction (DR6).

[0055] Referring to FIGS. 5a and 5b, there may be two vision systems (400). Although only one of the aforementioned vision systems (400) is illustrated for convenience of explanation, in this specification, the vision system (400) may be at least one or more. When the distance between the ends of the shim plate (100c) in the fifth direction (DR5) and / or the sixth direction (DR6) measured by the vision system (400) and the ends of the second slot die (100b) in the fifth direction (DR5) and / or the sixth direction (DR6) is outside the preset error range, the first motor (500a) and the second motor (500b) can be moved to adjust the position of the shim plate (100c).

[0056] Thereafter, when the vision system (400) confirms that the shim plate (100c) is within the target error range, the first motor (500a) and the second motor (500b) can move the first pin (300a) and the second pin (300b) in the fourth direction (DR4) to fix the position of the shim plate (100c).

[0057] Thus, the slot die coater (100) according to an embodiment of the present invention can adjust the position of the shim plate (100c) in the first direction (DR1), the second direction (DR2), the fifth direction (DR5), and the sixth direction (DR6), and apply the coating liquid (220) so as to have a target width spread at a target position on the substrate (210).

[0058] As described above, the preferred embodiments of the present invention have been described in detail. However, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the present invention.

Description of Reference Numerals

[0059] 100: Slot die coater 100a: First slot die 100b: Second slot die 100c: Shim plate 110a: First die lip 110b: Second die lip 110c: Shim plate end 200: Coating roll 210: Substrate 220: Coating liquid 300a, 300b: First and second pins 400: Vision system 500a, 500b: First and second motors

Claims

1. A slot die, At least one motor disposed inside the slot die, A shim plate disposed on the slot die, and A slot die coater capable of automatically adjusting the position of the shim plate, including at least one pin that passes through the shim plate and is connected to the motor and is movable by the motor.

2. The slot die coater capable of automatically adjusting the position of the shim plate according to Claim 1, characterized in that the pin is movable in a first direction in which a coating liquid is applied and a second direction opposite to the first direction.

3. The slot die coater capable of automatically adjusting the position of the shim plate according to Claim 2, characterized in that the pin is movable in a third direction which is the direction in which the pin passes through the shim plate and a fourth direction opposite to the third direction.

4. The slot die coater capable of automatically adjusting the position of the shim plate according to Claim 3, characterized in that the pin is movable in a fifth direction perpendicular to the first direction and the third direction and a sixth direction opposite to the fifth direction.

5. The slot die coater capable of automatically adjusting the position of the shim plate according to any one of Claims 1 to 4, characterized in that when the distance between the end of the shim plate measured by a vision system and the end of the slot die exceeds a preset error range, the motor moves the pin to adjust the position of the shim plate.

6. The slot die coater capable of automatically adjusting the position of the shim plate according to Claim 5, characterized in that there are a plurality of the motors and the pins respectively.

7. A step of measuring the distance between the end of the slot die and the end of the shim plate disposed on the slot die, A step of determining whether the distance is within a preset error range, and A method for adjusting the position of the shim plate of a slot die coater, including a step of adjusting the position of the shim plate according to the result of the determination.

8. The method for adjusting the position of the shim plate of a slot die coater according to Claim 7, characterized in that the step of adjusting the position of the shim plate proceeds by a pin connected to a motor disposed in the slot die through the shim plate.

9. The method for adjusting the position of the shim plate of the slot die coater according to claim 7, further comprising the step of fixing the shim plate after the step of adjusting the position of the shim plate.

10. The step of fixing the shim plate is characterized in that it proceeds by a pin connected to a motor disposed in the slot die through the shim plate, the method for adjusting the position of the shim plate of the slot die coater according to claim 9.

11. The method for adjusting the position of the shim plate of the slot die coater according to claim 7, further comprising the step of re-measuring the distance between the end of the shim plate and the end of the slot die after the step of adjusting the position of the shim plate.

12. The method for adjusting the position of the shim plate of the slot die coater according to claim 11, further comprising the step of generating an alarm when the distance between the end of the shim plate and the end of the slot die is outside the preset error range after the step of re-measuring.

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