JP3928538B2 - Control method and apparatus for air knife drying - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to an air knife drying method and apparatus for drying a thin substrate such as glass, ceramic, plastic, and metal by the air knife effect.
[0002]
[Prior art]
For example, in the manufacturing process of the liquid crystal panel, the surface of the glass substrate constituting the liquid crystal panel is cleaned when a predetermined processing process is introduced or after various processes are performed. The substrate is generally cleaned by using cleaning water made of pure water and spraying or dipping the cleaning water toward the substrate. And after washing | cleaning of a board | substrate, it is made to dry so that the droplet and liquid film adhering to the surface (in many cases front and back both surfaces) may be removed. As this substrate drying method, so-called air knife drying, in which thin strip-shaped pressurized air is supplied to the substrate surface, has been widely performed (see, for example, Patent Document 1).
[0003]
Air knife drying has an air knife nozzle having a slit-shaped pressurized air injection section, and jets high-pressure air from the air knife nozzle toward the substrate, and removes adhering liquid on the substrate surface by this air pressure. is there. The substrate is transported in a substantially horizontal state by a transport means such as a roller conveyor, for example, and the air knife nozzle is orthogonal to the transport means at a position in the middle of transport by the transport means, or with respect to the direction orthogonal. It is set as the structure which faces so that it may have a predetermined angle. In addition, the air injection direction from the air knife nozzle is set to have a predetermined angle with respect to the substrate surface, for example, an angle of about 45 °.
[0004]
As described above, by performing air knife drying while the substrate is horizontally transported, a predetermined treatment is performed on the substrate, the substrate is then cleaned, and drying after cleaning is continuously performed inline. Thus, there is an advantage that processing efficiency and smoothness are ensured.
[0005]
[Patent Document 1]
JP 2001-227868 A
[0006]
[Problems to be solved by the invention]
By the way, in order to achieve the complete drying of the substrate by the air knife nozzle, that is, in order to completely remove the droplets and liquid film adhering to the substrate, the drying is performed according to the size of the substrate and the surface condition of the substrate The conditions must be changed. Here, the surface state of the substrate is the degree of wettability and water repellency on the surface of the substrate, and a certain type of film may be formed on the surface of the substrate. Drying conditions will change. Here, the substrate drying conditions vary depending on the structure of the air knife nozzle, for example, the slit width and length of the nozzle opening, the angle with respect to the substrate, etc., but generally these conditions are constant. It is common. The variable drying conditions include the flow rate of pressurized air supplied from the air knife nozzle and the substrate transport speed.
[0007]
From the above, if the size or type of the substrate to be dried is different, the drying accuracy of the substrate is maintained by adjusting at least one or both of the supply flow rate of the pressurized air and the conveyance speed of the substrate. Must do so. For example, when the size of the substrate is increased, complete drying cannot be expected unless the flow rate of the pressurized air is increased by that amount or the conveyance speed of the substrate is decreased. In addition, even when the wettability on the surface of the substrate is high, it is necessary to promote the separation of the liquid from the substrate surface by increasing the flow rate of the pressurized air or by reducing the transport speed of the substrate. On the other hand, when the surface of the substrate has a certain degree of water repellency, it can be sufficiently dried with a small amount of pressurized air. And the wettability and water repellency of this substrate not only depend on the material and surface finishing accuracy of the substrate itself, but also when the film is applied on the surface of this substrate, the film type, pattern shape, etc. It also depends on.
[0008]
Therefore, each time the size or type of the substrate to be processed is different, the supply flow rate of the pressurized air to the air knife nozzle and the substrate transport speed must be adjusted to set up the substrate. Conventionally, this setup work has been performed manually by the operator. For this reason, work is extremely skillful, and every time the drying conditions are changed, it is necessary to confirm that the substrate has run out of liquid. For this reason, it takes a long time to accurately adjust the drying conditions. There is a problem that becomes.
[0009]
Further, from the viewpoint of the operability of the apparatus, it is not necessary that a substrate to be processed can be completely dried by giving a certain drying condition. There are cases where the supply flow rate of pressurized air from the air knife nozzle is excessive and the substrate is sufficiently dried even with a lower supply flow rate. Depending on how the drying conditions are given, a wasteful amount of pressurized air is consumed. For example, problems may occur in terms of running costs in the apparatus.
[0010]
Further, conventionally, once the drying conditions are adjusted, the readjustment is generally not performed unless the substrate to be processed is changed. However, even for the same type of substrate, the surface state of the substrate may change for some reason, and when these substrates are dried under the same drying conditions, there is no possibility of uneven drying. Not necessarily.
[0011]
The present invention has been made in view of the above points, and an object of the present invention is to make it possible to easily and smoothly give optimum drying conditions to various substrates.
[0012]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, a first invention of an air knife drying method is provided for at least one surface of a substrate while conveying the substrate in a flat flow along the conveying means. The liquid adhering to the substrate is removed by the pressurized air ejected from the air knife nozzle. Air knife drying Do Hitting After the pressurized air sprayed from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is attached to the substrate and the portion where the liquid is not attached is detected as the drying start position, and the air knife Measure the distance in the transport direction of the substrate from the position of the nozzle to the drying start position, compute this measurement result, determine whether this measured distance is in the proper range, based on this determination result, From the position of the air knife nozzle to the drying start position The flow rate of pressurized air from the air knife nozzle or the transport speed of the substrate is adjusted so that the distance is within a predetermined range. At least one It is characterized by control.
[0013]
Moreover, as 2nd invention, while conveying a board | substrate in the state of a flat flow along a conveyance means, with respect to both front and back of this board | substrate The liquid adhering to the substrate is removed by the pressurized air ejected from the air knife nozzle. Air knife drying Do Hitting After the pressurized air sprayed from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is attached to the substrate and the portion where the liquid is not attached is detected as the drying start position, and the air knife Measure the distance in the transport direction of the substrate from the position of the nozzle to the drying start position, compute this measurement result, determine whether this measured distance is in the proper range, based on this determination result, From the position of the air knife nozzle to the drying start position The flow rate of pressurized air from the air knife nozzle or the conveyance speed of the substrate so that the distance is within a predetermined range At least one of It is characterized by controlling.
[0014]
Furthermore, as a third aspect of the invention, while the substrate is transported in a flat flow along the transport means, at least on the surface side of the substrate. The liquid adhering to the substrate is removed by the pressurized air sprayed from the air knife nozzle. Air knife drying Do Hitting After the pressurized air ejected from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is adhered and the portion where the liquid is not adhered on the substrate is detected as the drying start position, Measure the distance in the transport direction of the substrate from the position of the air knife nozzle to the drying start position, calculate this measurement result, determine whether the measured distance is in the proper range, When the drying start end position is separated from the position of the air knife nozzle by a predetermined distance or more, control is performed so that the injection flow rate of the pressurized air of the air knife nozzle is changed to a small amount.
[0015]
And the invention relating to the air knife drying apparatus is adapted to at least one surface of the substrate while transporting the substrate in a flat flow along the transport means. The liquid adhering to the substrate is removed by the pressurized air ejected from the air knife nozzle. Air knife drying Do And After the pressurized air ejected from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is attached to the substrate and the portion where the liquid is not attached is detected as the drying start position, and the air knife nozzle Measure the distance in the substrate transport direction from the position of the substrate to the drying start position Distance measuring means, and the distance measuring means Judge whether the distance measured in is within the proper range, The distance from the air knife nozzle so that the distance from the position of the air knife nozzle to the drying start position is within a predetermined range. Pressurization It is characterized by comprising control means for controlling the air injection flow rate to change.
[0016]
Here, the board | substrate used as the object of air knife drying is a thin board | substrate which has shapes, such as a rectangle, a square, and a circle. The material of the substrate is glass, ceramic, plastic, metal or the like. And even if the substrate is a solid one (for example, in the case of a glass substrate, it is in the form of a raw glass), it is also intended for a substrate on which a film or pattern of a kind that is a means of coating or the like is formed. . Air knife drying is performed on at least one surface of the substrate, particularly the front surface side, but preferably air knife drying is performed on both the front and back surfaces. The substrate is dried while being transported in a flat state by the transport means. Here, the flat flow state includes a horizontal state, and includes a state where the horizontal state is slightly tilted to the left and right, or tilted back and forth. When drying both surfaces of the substrate, air knife nozzles are arranged above and below the conveying means, but the air knife nozzles are arranged on a plane parallel to the conveying surface of the substrate by the conveying means. The air knife nozzle may be disposed in a direction orthogonal to the substrate transport direction, but from the viewpoint of drying efficiency, the air knife nozzle is disposed at a predetermined angle with respect to the substrate transport direction on a surface parallel to the transport surface. It is desirable.
[0017]
While the air knife nozzle is fixedly held at a predetermined position, the substrate is transported by the transporting means, and the front surface or both the front and back surfaces are dried during this time. The drying start position of the substrate refers to a portion where the pressurized air from the air knife nozzle enters (contacts) the substrate and the liquid is removed from the substrate surface by the action of the air pressure, and a portion where the liquid is still attached. It is the boundary part. Here, the removal of the liquid means a state in which the droplets or liquid film adhering to the substrate has been removed, and does not require removal of moisture at the molecular level. The drying start position of the substrate can be detected by various means. However, the simplest and highly accurate detection is possible by using an optical detection means, that is, an optical sensor. That is, light is emitted from the light emitting means to the substrate, the reflected or transmitted light is detected, and the change point of the light amount is set as the drying start position. Since the air knife nozzle is fixedly arranged, the distance from the drying start position to the air knife nozzle is measured by calculating the distance between the drying start position on the substrate and the air knife nozzle by the optical detection means. it can. Although an area sensor can be used as the configuration of the optical sensor, it is desirable to use a line sensor from the viewpoint of miniaturization and compactness and from the viewpoint of simplification of signal processing. The line sensor is provided in parallel with the substrate transport direction, but may be provided in one or more places.
[0018]
An object of control performed based on the result of the distance measurement described above is a substrate conveyance speed or an air injection flow rate (pressure and flow velocity). However, in addition to these, other means such as an inclination angle of an air knife nozzle may be controlled. Here, in the case where the substrate is continuously processed, it may not always be advantageous to change the substrate conveyance speed only during the drying step because of the relationship with other steps. Controlling the injection flow rate of pressurized air from the air knife nozzle is superior to controlling the substrate transport speed in terms of ease of control, response speed, and the like.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. Needless to say, the present invention is not limited to the embodiments described below.
[0020]
First, FIG. 1 shows a schematic configuration of a substrate drying process. In the figure, S is a substrate, 1 is a liquid draining stage, and 2 is a drying stage. The substrate S is cleaned in the previous step, for example, by shower cleaning or the like, and is transferred to the drying stage 2 while reducing the amount of the adhered liquid on the surface as much as possible and ensuring that the entire surface is wet with the liquid. The
[0021]
The liquid draining stage 1 and the drying stage 2 are each defined by a housing, and a partition wall 3 is provided between the stages 1 and 2. The liquid draining stage 1 is provided with a carrying-in part 1a for the substrate S, the drying stage 2 is provided with a carrying-out part 2a for the substrate S, and the partition 3 is formed with a narrow opening 3a that constitutes the traveling path of the substrate S. Has been. In the liquid draining stage 1, pure water supply means 4 is installed, and the entire surface of the substrate S is kept wet by the pure water dropped by the pure water supply means 4. Further, an air knife drying device 5 is provided in the drying stage 2 so as to sandwich the substrate S therebetween. The drying stage 2 is in a positive pressure state so that mist of the cleaning liquid does not enter, and the liquid draining stage 1 is in a negative pressure state. For this purpose, an atmospheric pressure device 6 is installed on the drying stage 2, and an exhaust unit 7 is mounted on the liquid draining stage 1. Furthermore, a drainage unit 8 is provided at the lower part of the liquid draining stage 1.
[0022]
Here, the substrate S is made of, for example, a rectangular thin glass substrate, and the substrate S is inclined substantially horizontally or slightly left and right from the previous process, through the liquid draining stage 1 and the drying stage 2 to the subsequent process. It is transported in the state where Therefore, in order to transport the substrate S, the conveyor means 10 as the transport means shown in FIG. 2 is provided. The conveyor means 10 is composed of, for example, a roller conveyor. The conveyor means 10 is composed of a rotating shaft 11 provided with a predetermined pitch interval and a plurality of rollers 12 mounted in the longitudinal direction thereof, and rollers 12a at both ends. , 12a are provided with a flange 13 continuously. The substrate S is positioned so that its long side is in contact with both flanges 13 and 13 and is transported in the direction of the arrow in FIG. 2 with its surface horizontal. For this purpose, a gear 14 is connected to one end of each rotary shaft 11, and the gears 14 of each rotary shaft 11 are sequentially engaged via a transmission gear 15. When the gear 14 is rotationally driven, all the rotating shafts 11 are rotated and the substrate S is transported.
[0023]
The substrate S that has passed through the liquid draining stage 1 moves from the opening of the partition wall 3 to the drying stage 2 and is dried using an air knife drying device 5 provided on the drying stage 2. As is apparent from FIGS. 3 and 4, the air knife drying device 5 has an air knife nozzle 20, and the air knife nozzle 20 has an elongated and long casing 21, and pressurized air is contained in the casing 21. A pressurized air chamber 22 into which is introduced is formed. An air outflow passage 23 is formed in the side surface of the casing 21, and the tip of the air outflow passage 23 is a narrow slit-shaped nozzle port 24. The air outflow passage 23 has a passage length necessary for rectification so as to form a thin line when air is ejected from the nozzle port 24. Further, one or a plurality of air supply pipes 25 for supplying pressurized air into the pressurized air chamber 22 are connected to the casing 21.
[0024]
The air knife nozzle 20 having the above configuration is arranged in the drying stage 2 so as to sandwich the transport path of the substrate S composed of the conveyor means 10. Therefore, when the upper air knife nozzle is 20U, the lower air knife nozzle is 20L, the nozzle ports thereof are 24U, 24L, the front side of the substrate S is SU, and the back side is SL, the air knife nozzle 20U. And 20L are spaced apart from the front and back surfaces SU and SL of the substrate S by an equal distance, and are located on a plane parallel to the surfaces SU and SL. Further, the depression angle α (see FIG. 6) of the pressurized air ejected from the nozzle port 24U in the air knife nozzle 20U is the same as the elevation angle α of the nozzle port 24L of the air knife nozzle 20L, and the substrate S by the conveyor means 10 It arrange | positions so that it may have a predetermined angle toward the back side of a conveyance direction.
[0025]
Further, the air knife nozzles 20U and 20L are not arranged in a direction orthogonal to the transport direction of the substrate S, but are a predetermined angle within the plane described above. θ (FIG. 2) is arranged to be inclined. Further, the nozzle openings 24U, 24L of the air knife nozzles 20U, 20L extend over the entire length in the direction intersecting the transport direction with respect to the surface of the substrate S transported on the conveyor means 10.
[0026]
With the entry of the pressurized air into the substrate S as a boundary, the cleaning liquid is pushed away from the entry of the pressurized air in the direction of the arrow in FIG. After entering, the liquid flows along the surface of the substrate S, and during this time, the liquid is peeled off from the surface of the substrate S by the action of air pressure. In FIG. 5, a line B indicates a substrate drying start end, and a position P2 (see FIG. 6) of the substrate drying start end is that a droplet or liquid film of the cleaning liquid is discharged from the substrate S by the pressurized air. This is the boundary between the completely removed part and the part where the cleaning liquid is still attached.
[0027]
As shown in FIG. 6, the angle of entry of the pressurized air into the substrate S coincides with the elevation angle α of the air knife nozzle 20, but the liquid is actually peeled off and removed from the substrate S when the pressurized air is removed from the substrate. After being oriented in a direction parallel to S. Accordingly, the size and surface state of the substrate S, that is, whether the surface is wettable, whether or not a film is formed on the surface, the type of film, and the pressure and flow velocity of the pressurized air from the air knife nozzle 20, the air knife nozzle 20 The substrate drying start position P2 varies depending on the thickness, spread angle, and the like of the pressurized air.
[0028]
The size and surface of the substrate S on which the drying process is performed in order to ensure the integrity of the air knife drying on the substrate S, to efficiently dry the substrate S, and to enable energy saving operation of the apparatus. Depending on the state, at least one of the conveyance speed of the substrate S and the supply flow rate of pressurized air from the air knife nozzle 20 is controlled.
[0029]
Now, when air knife drying is performed on the substrate S, as shown in FIG. 6, the pressurized air enters the substrate S at a position P <b> 1 that is a predetermined distance away from the tip of the air knife nozzle 20. Accordingly, the liquid on the substrate S does not substantially move up to this position P1. From this entry position, the pressurized air is directed in a direction parallel to the substrate S. At this time, the pressurized air acts on the liquid adhering to the substrate S and tries to peel off from the surface of the substrate S. Then, when the pressurized air advances from the front end position P0 of the air knife nozzle 20 to the position P2 in the front of the transport direction of the substrate S, the droplets and the liquid film come to be peeled from the substrate S, and this position is the substrate drying. This is the starting position. That is, a distance L exists between the tip position P0 of the air knife nozzle 20 and the substrate drying start position P2.
[0030]
Incidentally, the distance L from the position P0 of the air knife nozzle 20 to the substrate drying start position P2 has an appropriate range. When this distance is too long, the flow rate of the pressurized air ejected from the air knife nozzle 20 is excessive, and wasteful pressurized air is consumed. In addition, in the width direction of the substrate S, the substrate drying start position P2 is not stable, that is, does not become a linear state but has a zigzag shape. It may not be said that there is a possibility that liquid droplets remain and there is no possibility of uneven cleaning. On the other hand, when the distance is too short, the liquid may not be completely removed from the surface depending on the amount of the liquid attached to the substrate S. In particular, the drying action of the substrate S is also exerted from the pressurized air entry position P1 to the substrate drying start position P2, and if the distance between them is not sufficiently maintained, the drying accuracy deteriorates, The drying integrity of the substrate S is impaired.
[0031]
As described above, when the substrate S is transported and dried while the air knife nozzle 20 is disposed at a predetermined position, the substrate drying start position P2 is always within the predetermined range. That is, in FIG. 5, being within the appropriate distance range X improves the drying accuracy and efficiency, and stabilizes the substrate drying start position P2. It is the most desirable in planning. Even if the size, wettability, etc. of the substrate S, whether or not a film is formed on the surface, and the type of the film change, the substrate drying start position P2 is located within the appropriate distance range X. If so, high drying accuracy can be obtained.
[0032]
From the above, in the present invention, the substrate drying start position P2 during the drying of the substrate S is measured, and the substrate drying start position P2 is controlled to be positioned within the appropriate distance range X. . Here, if the conveyance speed of the substrate S is changed or the flow rate of the pressurized air ejected from the air knife nozzle 20 is changed, the substrate drying start position P2 can be moved. That is, the drying conditions of the substrate S can be changed by the transport speed of the substrate S and the air flow rate. Here, extremely high drying accuracy is required on the front surface side of the substrate S, and the back surface side thereof is not required to have very high drying accuracy. Therefore, it is the surface side that needs to strictly set the drying conditions performed according to the substrate S. However, the substrate drying start position P2 may be adjusted as necessary to improve the drying accuracy on the back side.
[0033]
Therefore, the substrate drying start position P2 is first detected. That is, in FIG. 5, 30 is a line sensor constituting the distance measuring means, and this line sensor 30 is a boundary position between the portion where the liquid adheres to the substrate S and the portion where the liquid does not adhere, that is, the substrate drying. The start position P2 is detected based on, for example, the difference in the amount of reflected light. The line sensor 30 is arranged in the direction in which the substrate S is transported. In the configuration shown in the figure, one line sensor 30 is provided at almost the center of the substrate S. In order to detect the substrate drying start position P2 more accurately, a plurality of line sensors may be provided in parallel.
[0034]
A signal related to the substrate drying start position P2 detected by the line sensor 30 is taken into the control circuit 31. Then, the control circuit 31 calculates the distance from the air knife nozzle 20 to the substrate drying start position P2, and determines whether the calculation result is within the appropriate distance range X, longer or shorter. become. When it is determined that the distance is outside the appropriate distance range X, the substrate drying start position P2 is controlled to be within the appropriate range by adjusting the drying conditions of the air knife nozzle 20.
[0035]
Here, the adjustment of the drying conditions of the air knife nozzle 20 is the supply flow rate of the pressurized air ejected from the air knife nozzle 20 in the present embodiment. For this purpose, an auto damper 32 is provided in the air supply pipe 25 that supplies pressurized air to the air knife nozzle 20. The auto damper 32 automatically increases / decreases the flow rate of pressurized air supplied from the air supply pipe 25 to the air knife nozzle 20 based on an input signal.
[0036]
Thus, when the substrate S is dried by the substrate drying apparatus, the most appropriate cleaning conditions are set according to the size and surface state of the substrate S. For this purpose, the substrate S that has been cleaned, which is the pre-process of the drying process, is introduced into the drying stage 2 through the liquid draining stage 1 in the drying process at a predetermined transport speed by the conveyor means 10. Then, a predetermined flow rate of pressurized air is supplied from the air supply pipe 25 to the air knife nozzle 20, and the pressurized air is jetted toward the substrate S from the nozzle port 24. As a result, the drying of the substrate S is started. The dry state of the substrate S is detected by the line sensor 30 at the substrate drying start position P2.
[0037]
When the distance from the air knife nozzle 20 at the substrate drying start position P2 detected by the line sensor 30 is longer than the appropriate distance range X, the flow rate of the pressurized air supplied from the air knife nozzle 20 is excessive. The control signal from the control circuit 31 is controlled to close the auto damper 32, that is, to reduce the flow rate of the pressurized air. As a result, the flow rate of the pressurized air ejected from the air knife nozzle 20 via the air supply pipe 25 is reduced, and as a result, the distance from the air knife nozzle 20 to the substrate drying start position P2 is shortened. When the substrate drying start position P2 enters the appropriate distance range X, and more desirably, when the substrate drying start position P2 reaches the intermediate position in the appropriate distance range X, the flow rate of the pressurized air by the auto damper 32 is maintained in that state.
[0038]
As a result, consumption of pressurized air can be saved, and the apparatus can be operated in an energy-saving manner. Further, in the width direction of the substrate S, the line at the substrate drying start position P2 becomes stable, and there is no possibility that minute droplets remain on the surface of the substrate S, and the drying accuracy is improved.
[0039]
On the other hand, when it is determined that the distance from the air knife nozzle 20 at the substrate drying start position P2 detected by the line sensor 30 is shorter than the appropriate distance range X, the automatic damper 32 is controlled to open based on the signal from the control circuit 31. As a result, the flow rate of the pressurized air supplied from the air knife nozzle 20 toward the substrate S increases. As a result, the distance from the air knife nozzle 20 to the substrate drying start position P2 is increased, and the distance is shifted to the appropriate distance range X, more preferably to the intermediate position of the appropriate distance range X. This eliminates the occurrence of uneven drying on the substrate S and allows highly accurate drying.
[0040]
As described above, the drying conditions are adjusted so as to be optimal for the substrate S. This adjustment displaces the substrate drying start position P2, and therefore the supply flow rate of pressurized air by the air knife nozzle 20 is adjusted. It is also possible to adjust the conveyance speed of the substrate S by the conveyor means 10 in addition to controlling the above. That is, as shown in FIG. 5, when it is determined that the substrate drying start position P2 is long, the drive circuit 33 (specifically, an electric motor or the like) of the conveyor means 10 is controlled from the control circuit 31, and the substrate S Increase the transport speed. As a result, the substrate drying start position P2 is shortened and displaced within the appropriate distance range X. Conversely, when the substrate drying start position P2 is too short, the substrate drying start position P2 is displaced within the appropriate distance range X by reducing the transport speed of the substrate S by the conveyor means 10.
[0041]
As described above, at least one of the control of the supply flow rate of the pressurized air by the air knife nozzle 20 by the auto damper 32 and the control of the transport speed of the substrate S by the driving unit 33 is performed. It is possible to make rough adjustments by changing the air supply flow rate, and fine adjustment by controlling the transport speed of the substrate S. Further, the substrate drying start position P2 is adjusted at an initial stage and may not be adjusted again as long as the same substrate S is processed. However, it is also possible to set so that the substrate drying start position P2 is adjusted every time one substrate S is dried.
[0042]
【The invention's effect】
Since the present invention is configured as described above, it is possible to easily and smoothly give optimum drying conditions to various substrates, thereby significantly improving the drying accuracy and drying efficiency of the substrates and consuming the compressed air. The effect is that the amount can be minimized.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a substrate drying apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view of a drying stage.
FIG. 3 is a cross-sectional view of an air knife nozzle.
FIG. 4 is an external perspective view of an air knife nozzle.
FIG. 5 is a diagram illustrating the configuration of a drying condition setting mechanism.
FIG. 6 is an operation explanatory diagram of an air knife nozzle.
[Explanation of symbols]
1 Liquid cutting stage
2 Drying stage
5 Air knife dryer
10 Conveyor means
20 Air knife nozzle
23 Air outflow passage
24 Nozzle port
25 Air supply piping
30 line sensor
31 Control circuit
32 Auto damper
33 Drive means

Claims (4)

An air knife so as to remove liquid adhering to the substrate by pressurized air ejected from an air knife nozzle on at least one surface of the substrate while the substrate is transported in a flat flow along the transport means. hitting to dry,
After the pressurized air ejected from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is attached to the substrate and the portion where the liquid is not attached is detected as the drying start position, and the air knife Measure the distance in the transport direction of the substrate from the nozzle position to the drying start position,
This measurement result is processed to determine whether this measured distance is in the proper range,
Based on the determination result, at least one of the flow rate of pressurized air from the air knife nozzle or the transport speed of the substrate is set so that the distance from the position of the air knife nozzle to the drying start position is within a predetermined range. The air knife drying method characterized by controlling. While transferring the substrate in a flat flow along the transfer means , air knife drying is performed so as to remove the liquid adhering to the substrate by the pressurized air sprayed from the air knife nozzle on both the front and back surfaces of the substrate. In doing
After the pressurized air ejected from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is attached to the substrate and the portion where the liquid is not attached is detected as the drying start position, and the air knife Measure the distance in the transport direction of the substrate from the nozzle position to the drying start position,
This measurement result is processed to determine whether this measured distance is in the proper range,
Based on the determination result, at least one of the flow rate of pressurized air from the air knife nozzle or the transport speed of the substrate is set so that the distance from the position of the air knife nozzle to the drying start position is within a predetermined range. The air knife drying method characterized by controlling. While transporting the substrate in a flat flow along the transport means, the liquid adhering to the substrate is removed by pressurized air ejected from an air knife nozzle on at least the surface side of the substrate. When drying the air knife,
After the pressurized air ejected from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is adhered and the portion where the liquid is not adhered on the substrate is detected as the drying start position, Measure the distance in the transport direction of the substrate from the position of the air knife nozzle to the drying start position,
This measurement result is processed to determine whether this measured distance is in the proper range,
According to the determination result, when the drying start end position is separated from the position of the air knife nozzle by a predetermined distance or more, control is performed so that the injection flow rate of the pressurized air of the air knife nozzle is changed to a small amount. Air knife drying method. An air knife so as to remove liquid adhering to the substrate by pressurized air ejected from an air knife nozzle on at least one surface of the substrate while the substrate is transported in a flat flow along the transport means. in those dry,
After the pressurized air sprayed from the air knife nozzle enters the substrate, the boundary between the portion where the liquid is attached to the substrate and the portion where the liquid is not attached is detected as the drying start position, and the air knife nozzle Distance measuring means for measuring the distance in the transport direction of the substrate from the position of the substrate to the drying start position ;
It is determined whether or not the distance measured by the distance measuring means is within an appropriate range, and the determination result indicates that the distance from the air knife nozzle position to the drying start position is within a predetermined range. An air knife drying apparatus comprising control means for controlling the injection flow rate of the pressurized air to change.

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