JP4103006B2 - Coating equipment - Google Patents

Description

  The present invention applies the coating liquid fed to the liquid reservoir chamber of the coating head to the surface of the web that runs while being wound around the outer peripheral surface of the rotating backing roll, and is applied with the measuring tool of the coating head. The present invention relates to a coating apparatus that controls a gap between a web and a measuring tool so that a coating liquid in a liquid storage chamber maintains a constant fluid pressure value when coating is performed with a thickness determined.

There exists a thing of patent document 1 as this kind of coating apparatus. The coating apparatus described in Patent Document 1 is surrounded by a backing roll that rotates by forming a web conveyance path on an outer peripheral surface, a liquid stop wall that faces the web conveyance path of the backing roll, and a measuring tool (doctor). A coating head with a liquid reservoir chamber extending in the transverse direction of the web conveyance path, a liquid supply device for pumping the coating liquid to the liquid reservoir chamber via the liquid supply path, and a coating head toward the backing roll And a control device that controls the clearance between the backing roll and the measuring surface (doctor edge) of the measuring tool by advancing and retreating, and the control device includes a pressure detecting means for detecting the liquid pressure value of the coating liquid in the liquid reservoir chamber, and a setting Deviation calculation means for calculating a deviation between the hydraulic pressure value and the hydraulic pressure value detected by the pressure detection means, and a fluctuation speed calculation for calculating a fluctuation speed that is a fluctuation amount per unit time of the hydraulic pressure value detected by the pressure detection means. Means and the deviation calculated by the deviation calculating means Change value determining means for determining a change value of the gap from the fluctuation speed calculated by the fluctuation speed calculating means, and control for controlling the gap adjusting means to change the gap by the change value determined by the change value determining means. Means. The change value determination means determines the change value from the first to ninth rules stored in the storage means.
Japanese Patent No. 2932147

However, the conventional coating apparatus described in Patent Document 1 has the following problems.
(1) As the operating state of the coating progresses, the liquid pressure in the liquid storage chamber may vary slowly. For example, when the temperature of the coating device changes slowly with the progress of coating, the gap between the backup roll and the measuring instrument slowly changes due to thermal deformation of the components of the coating device, or the progress of coating At the same time, as the thickness of the web changes slowly, when the gap between the web and the measuring instrument changes slowly, the hydraulic pressure in the liquid storage chamber changes slowly. However, in the conventional coating apparatus, by adjusting the gap between the backup roll and the measuring tool while considering the fluctuation speed of the hydraulic pressure value, the fluctuation of the hydraulic pressure becomes rapid, for example, the web line speed is increased. In the above case where the fluid pressure slowly changes without the fluid pressure value changing speed appearing, the gap adjustment amount remains at zero, causing a problem that cannot be handled. .
(2) Since the change value determination means determines the change value from the first to ninth rules stored in the storage means, a lot of work is required in the preparation stage for creating the rule table for determining the change value. There's a problem.

  Therefore, the present invention was devised in view of the above-described problems of the prior art, and can deal with the case where the liquid pressure in the liquid storage chamber fluctuates slowly and can be easily prepared before control. The purpose is to provide construction equipment.

In order to be able to cope with the case where the liquid pressure in the liquid storage chamber fluctuates slowly, the means adopted by the present invention according to claim 1 includes a backing roll that rotates by forming a web conveyance path on the outer peripheral surface. A coating head in which a liquid retaining wall surrounded by a liquid stop wall and a measuring instrument facing the web conveyance path of the backing roll is extended in the transverse direction of the web conveyance path, and a feed for feeding the coating liquid to the liquid reservoir In a coating apparatus comprising a liquid device and a control device that adjusts the gap between the backing roll and the measuring tool by moving the coating head forward and backward toward the backing roll, the control device is a waiting time zone described later. In order to obtain a coating film with a predetermined thickness from the detection value detected at each detection cycle of the hydraulic pressure detector, which includes a hydraulic pressure detector that periodically measures the hydraulic pressure of the coating liquid with a detection cycle shorter than the length set as the hydraulic pressure of the required coating liquid required value The time determined at a rate inversely proportional to the magnitude of the absolute value of the deviation obtained by subtraction, and the rate obtained by dividing the required value by the absolute value of the deviation, with the shortest time that can adjust the gap as the reference time When the absolute value of the deviation is zero, the standby time zone in which the gap is not adjusted only for a preset time and the control time zone in which the gap is adjusted by a set change amount are alternated. In the control time zone, the coating apparatus is characterized in that the gap is adjusted by moving the coating head forward and backward so as to reduce the absolute value of the deviation. In addition, as a part which measures the liquid pressure of a coating liquid, there exists a downstream of the liquid supply path which leads to a liquid reservoir or a liquid reservoir. When adjusting the gap by advancing and retracting the coating head, when the deviation is positive, the coating head is moved away from the backing roll, and conversely when the deviation is negative, backing is performed. The coating head is advanced so as to approach the roll.

In the first aspect of the present invention, the coating liquid in the liquid storage chamber surrounded by the liquid stop wall and the measuring device is applied to the web traveling on the web conveyance path of the backing roll and the traveling web. A coating film is passed through the gap between the measuring tool and a coating film, and the coating liquid amount consumed as a coating film is supplied from a liquid storage chamber by pressure feeding with a liquid feeder. At this time, the liquid pressure of the coating liquid needs to be set to the required value according to the amount of the coating liquid consumed as a coating film from the liquid reservoir, but the operating state of the coating progresses. When the fluid pressure of the coating liquid changes slowly and deviates from the required value, the control time zones that appear sequentially with a standby time zone in which the gap between the backing roll and the measuring device is not adjusted In addition, in order to reduce the absolute value of the deviation obtained by subtracting the required value from the detection value of the hydraulic pressure detector, control is performed to adjust the gap by moving the coating head forward and backward, and the hydraulic pressure is stepped to the required value. To be close to. The present invention shortens the time of the standby time zone as the absolute value of the deviation increases and increases the frequency of appearance of the control time zone. Conversely, the time of the standby time zone decreases as the absolute value of the deviation decreases. Increase the frequency to lower the appearance frequency of the control time zone.

In order to make it easy to set the change amount of the control time zone, the means adopted by the present invention according to claim 2 is that the change amount set in the control time zone is determined when the absolute value of the deviation is zero. The coating apparatus according to claim 1, wherein the coating apparatus is set to zero and is increased at a rate proportional to the absolute value of the deviation. Note that the amount of change may be increased at a rate proportional to the absolute value of the deviation within the range of the limit value.
In the present invention described in claim 2, the change amount of the gap in the control time zone can be set according to the magnitude of the absolute value of the deviation.

According to the first aspect of the present invention, as the absolute value of the deviation increases, the waiting time period is shortened to increase the appearance frequency of the control time period, and conversely, as the deviation absolute value decreases. The coating head is designed to reduce the absolute value of the deviation in each control time zone that appears successively with the standby time zone in between by increasing the time zone time and lowering the appearance frequency of the control time zone. Control is performed to adjust the gap by advancing and retreating, and the fluid pressure of the coating liquid is controlled so as to approach the required value step by step, so it can be handled regardless of the factors that cause the fluid pressure in the reservoir chamber to fluctuate slowly. And a predetermined coating thickness can be obtained. In addition, since the present invention can uniquely set the waiting time zone with the required value and the absolute value of the deviation, it is possible to easily set the waiting time zone with the optimum time length, and the preparation stage before performing the control. Becomes easier.

According to the second aspect of the present invention, since the amount of change of the gap in the control time zone can be set according to the magnitude of the absolute value of the deviation, the preparation stage before performing the control is simplified.

  A coating apparatus according to the present invention will be described based on an embodiment shown in the drawings. 1 to 3 show an embodiment of a coating apparatus according to the present invention, FIG. 1 is a front view of a coating state shown in a skeleton manner, and FIG. 2 is a coating head 5 of a coating apparatus main body 2. And (A) is a plan view showing the backing roll 6 by a two-dot chain line, (B) is an enlarged left side sectional view, and FIG. 3 is detected by the hydraulic pressure detector 32. 6 is a timing chart showing a state in which the time zone setter 34 alternately sets the standby time zone A and the control time zone B.

  As shown in FIG. 1, the coating apparatus 1 according to the present embodiment includes a coating apparatus body 2 including a coating head 5 and a backing roll 6, and a coating liquid that pumps the coating liquid M to the coating head 5. A supply device 3 and a control device 4 for controlling a gap G between the measuring tool 15 of the coating head 5 and the backing roll 6 are provided. The coating apparatus main body 2 supports both shafts 8 and 8 of the backing roll 6 that is long in the left-right direction above the left and right fixed frames 7 and 7, and between the left and right fixed frames 7 and 7. 5 are arranged, and left and right moving devices 9 and 9 for moving the coating head 5 forward and backward from a coating position C below the backing roll 6 to a further backward retracted position D are provided. The left and right fixed frames 7 and 7 are formed of thick steel plates or the like, and are joined at appropriate positions such as below by a joining frame 10.

  The backing roll 6 forms a web conveyance path R (see FIG. 2B) on the outer peripheral surface 6a, and is driven by the driving device 11 to rotate. The drive device 11 includes a motor with a speed reducer joined to one shaft portion 6 b of the roll 6.

  As shown in FIG. 2, the coating head 5 has a liquid reservoir chamber 14 that can face the outer peripheral surface 6a of the backing roll 6 on the upper surface side between the front and rear head blocks 12 and 13 that are joined in a separable manner. It is long and recessed. The coating head 5 has a measuring tool (doctor) 15 on the back (web unloading side) facing the web conveyance path R of the backing roll 6, left and right liquid blocking walls 16, 17, and a front liquid blocking wall 18 that are detachable. A liquid reservoir chamber 14 which is attached and is surrounded by the measuring tool 15 and the liquid stop walls 16, 17, 18 and whose upper surface is open is formed. The weighing tool 15 has a weighing surface (doctor edge) 15a that determines the coating thickness on the upper surface of the backing roll 6 that can face the web conveyance path R.

  When the coating liquid M is pressure-fed from the coating liquid supply device 3 to the liquid supply port 19, the coating head 5 uniformly guides the coating liquid M to the entire region in the left-right direction of the liquid reservoir 14 to the web S. The coating liquid M that is brought into contact with the web S moving in the direction of the arrow J and moves is measured on the measuring surface 15 a of the measuring tool 15, and a coating film N having a predetermined thickness is applied to the web S. As the web S, a sheet-like material such as a plastic film, a metal foil, and a nonwoven fabric is selected.

  As shown in FIG. 1, the support base 20 that supports the coating head 5 is formed of a hollow square pipe or the like that extends in the left-right direction, and the left and right ends are joined to the connecting plates 21 of the left and right moving devices 9, 9. Has been. Each moving device 9 includes a connecting plate 21 disposed inside the fixed frame 7, and a vertical movement guide 22 disposed between the fixed frame 7 and the connecting plate 21 to guide the connecting plate 21 so as to move up and down. And an operation tool 23 that is arranged between the fixed frame 7 and the connecting plate 21 and moves the connecting plate 21 up and down. A gap adjusting device 24 of the control device 4 is disposed between the fixed frame 7 and the connecting plate 21, and does not adjust the upper stop position of the connecting plate 21, so that the measuring surface 15a of the measuring tool 15 (see FIG. 2). ) And the outer peripheral surface 6a of the backing roll 6 is adjusted.

  Although not shown in the drawing, the vertical movement guides 22 arranged on the left and right are joined to the front and rear rails joined to the fixed frame 7 and the front and rear rails, and joined to the connecting plate 21 and guided to the front and rear rails. It consists of a linear guide. Each of the left and right operation tools 23 is composed of a cylinder or an electric jack operated by fluid pressure (pneumatic pressure or hydraulic pressure), and joins the fixed end 23a to the fixed frame 7 and joins the output end 23b to the connecting plate 21. It is. The left and right operation tools 23, 23 advance and retract the output ends 23b, 23b in synchronization.

  As shown in FIG. 1, the left and right gap adjusting devices 24 constituting the control device 4 are attached to the connecting plate 21 so as to abut on the eccentric disk 24a pivotally supported on the fixed frame 7 and the eccentric disk 24a. The stopper 24b and a driving tool 24c having a motor with a speed reducer for adjusting the rotation angle of the eccentric disk 24a are provided. By adjusting the rotation angle of the eccentric disk 24a with the driving tool 24c, the upper coating position C The coating head 5 positioned at the position is moved forward and backward toward the backing roll 6 to adjust the gap G between the measuring surface 15a (see FIG. 2) of the measuring tool 15 of the coating head 5 and the outer peripheral surface 6a of the backing roll 6. It has become. When each gap adjusting device 24 uses a stepping motor whose rotation angle changes depending on the number of input pulses as the motor of the driving tool 24 c, the gap adjusting device 24 can select the motor rotation direction and the number of pulses as appropriate so that the backing roll 6 The direction and amount of movement of the coating head 5 that moves forward and backward can be determined. When a servo motor having a constant rotation speed is used, the direction of movement of the coating head 5 can be selected by appropriately selecting the motor rotation direction and the motor rotation time. And the amount of movement can be determined. Each gap adjusting device 24 uses the eccentric size of the eccentric disk 24a and the minimum rotation angle of the output part of the motor with a speed reducer of the driving tool 24c as the minimum value of the movement amount (change amount when controlling) of the coating head 5. Although it is determined by the processing capability of the control system such as, it can be selected from the range of 0.1 μm to 1.0 μm.

  As another aspect of the gap adjusting device 24, although not shown, a taper cotter is disposed on the fixed frame 7 so as to be able to advance and retreat, and a specific portion of the connecting plate 21 is brought into contact with the taper surface of the taper cotter. The position of the taper surface of the taper cotter with which the taper abuts is changed with a driving tool having a motor with a speed reducer, and the position of the taper surface of the taper cotter is adjusted by driving the driving tool, so that the coating position C located above is applied. The working head 5 is moved back and forth toward the backing roll 6 to adjust the gap G between the measuring surface 15 a of the measuring tool 15 of the coating head 5 and the outer peripheral surface 6 a of the backing roll 6. Also in this case, the minimum value of the movement amount of the coating head 5 (change amount when controlling) is selected in the same manner as described above.

  As shown in FIG. 1, the coating liquid supply device 3 includes a liquid feeding path 27 that feeds the coating liquid M from the coating liquid tank 26 to the liquid reservoir chamber 14 (see FIG. 2) of the coating head 5, and a feeding path. A pump 28 for feeding the coating liquid pressure provided in the middle of the liquid path 27 and a filter 29 provided in the liquid feed path 27 on the downstream side of the pump 28 are provided. The liquid feeding path 27 is configured by joining pipes and the like so as to be separable, and is easy to clean. As the pump 28, a Mono pump, a precision gear pump, a diaphragm pump, or the like is selected according to the type of the coating liquid, and the running speed of the web S and the thickness dimension of the coating film N are adjusted by adjusting the rotational speed of the drive motor 28a. The liquid delivery volume can be adjusted according to the conditions.

  In the coating apparatus 1 configured as described above, when the web S is guided to the backing roll 6 and the support base 20 is raised by the operation of the moving devices 9 and 9, as shown in FIG. It is supported at a coating position C that can be processed. When the coating liquid M is pumped in this state, the coating head 5 applies the coating film N to the web S as shown in FIG. The thickness of the coating film N is adjusted by changing the gap G between the measuring surface 15a of the coating head 5 and the web S by the operation of the left and right gap adjusting devices 24, 24 (see FIG. 1). This can be performed by adjusting the amount of liquid supplied by the supply device 3.

  In addition to the left and right gap adjusting devices 24, 24, the control device 4 includes a hydraulic pressure detector 32 for detecting the hydraulic pressure of the coating liquid M and a required value (setting of the hydraulic pressure) as shown in FIG. Value) required value setting device 33 for setting Ps, a time zone setting device 34 for alternately setting a waiting time zone A and a control time zone B, which will be described later, a measuring surface 15a of the coating head 5 and a web S (backing). An adjuster 30 is provided for outputting a command signal a for adjusting the gap G (see FIG. 2B) of the roll 6) to the driving tool 24c of each of the left and right gap adjusting devices 24.

  The liquid pressure detector 32 measures the liquid pressure value P1 of the coating liquid M in the liquid supply path 27 or the liquid reservoir chamber 14 (see FIG. 2). For example, the liquid pressure detector 27 or the liquid reservoir chamber 14 is used. And the measuring part 32b connected to the detection port of the detecting tool 32a, and the hydraulic pressure value P1 of the liquid feeding path 27 is obtained from the measured hydraulic pressure. In order to obtain the coating film N with high coating thickness accuracy, the detector 32a is disposed in the liquid supply path 27 having a smaller influence than the liquid reservoir chamber 14 having a large influence on the coating state. Is preferred. The hydraulic pressure detector 32 periodically detects the hydraulic pressure value P1, and as shown in FIG. 3, the detection cycle Ts is several milliseconds so as to be shorter than a time length Tw of a waiting time zone A to be described later. Or several tens of milliseconds.

  The required value setting unit 33 sets a required value Ps of the liquid pressure of the coating liquid M necessary for obtaining the coating film N having a predetermined thickness. From the test coating performed in advance and the past results, The required value Ps is set by selecting from the obtained hydraulic pressure values.

  As shown in FIG. 3, the time zone setting unit 34 alternates between a control time zone B for controlling the fluid pressure value of the coating liquid M by adjusting the gap G and a standby time zone A for which the fluid pressure value is not controlled. In addition to setting, the time lengths Tc and Tw of each time zone are set, and in the control time zone B, a command signal a for adjusting the gap G is sent from the adjuster 30 (see FIG. 1) to the left and right gap adjustment It is comprised so that it may output to the drive tool 24c of the apparatus 24. FIG.

  In the waiting time zone A, the absolute value of the deviation ΔP (that is, ΔP = P1−Ps) obtained by subtracting the required value Ps of the required value setting unit 33 from the detected value P1 of the hydraulic pressure detector 32. The time Tw determined at a rate inversely proportional to. Then, the time Tw in the standby time zone A is determined as follows.

(Example 1 of time Tw)
An expression in which the shortest time during which the gap G can be adjusted is a reference time To (for example, To = 2 msec), and is longer than the reference time To by a ratio obtained by dividing the required value Ps by the absolute value of the deviation ΔP. Obtained based on the rule of 1.
Tw = To × (Ps ÷ | ΔP |) (Formula 1)

(Example 2 of time Tw)
Tw = K2 ÷ | ΔP | (Formula 2)
K2 is appropriately set as a constant. For example, K2 is set as in Expression 3.
K2 = To × Ps ÷ K4 (Equation 3)
K4 is a constant, and is set in the range of 1 <K4 <100. If it is desired to increase the response speed, K4 is set large.

  The time Tw of the standby time zone A may be limited to a practical limit, rounded up for a short time, and rounded down for a long time, for example, in a range of 10 ms <Tw <5 seconds. The minimum value when setting the range of the time Tw is determined from the viewpoint of response limit of the control system and hunting prevention due to excessive response, and the maximum value is determined so as to be able to follow minute fluctuations in the hydraulic pressure.

  In the control time zone B, a change amount set from the adjuster 30 to the driving tool 24c of each of the left and right gap adjusting devices 24 so as to obtain the adjustment of the gap G to reduce the absolute value of the deviation ΔP. A command signal a corresponding to Gc is output, and each gap adjustment device 24 is operated by driving each driving tool 24c to adjust the gap G by a change amount Gc set. The time Tc for outputting the command signal a is appropriately determined according to the motor specifications of the driving tool 24c of each of the left and right gap adjusting devices 24.

The set change amount Gc is set to zero when the absolute value of the deviation ΔP is zero as shown in Equation 4, and is increased at a rate proportional to the magnitude of the absolute value of the deviation ΔP.
Gc = K3 × | ΔP | (Formula 4)
Note that K3 is appropriately set as a constant, and is set as shown in Equation 5, for example. K3 = (Gco ÷ Ps) × K5 (Formula 5)
K5 is a constant, and is set in the range of 10 <K5 <1000. If it is desired to increase the response speed, K5 is set large. Gco is a minimum change amount (for example, 0.1 μm) determined by the processing capability of the control system.

  The set change amount Gc may be set to a constant value regardless of the absolute value of the deviation ΔP. In this case, the change amount Gc is set in a range of 0.1 μm <Gc <10.0 μm, for example. The minimum value when setting the range of the change amount Gc is determined from the response limit of the control system, and the maximum value is determined from the viewpoint of preventing hunting due to overresponse.

  The motor of the driving tool 24c has a predetermined rotational speed and a relationship between the rotational speed and the change amount Gc. Therefore, the time Tc for outputting the command signal a corresponding to the change amount Gc is uniquely determined according to the change amount Gc.

  The time zone setter 34 outputs a command signal a from the adjuster 30 to the driving tool 24c of each gap adjusting device 24 in the control time zone B, so that the absolute value of the deviation ΔP is reduced. The coating head 5 is moved forward and backward by driving the driving tool 24c of each gap adjusting device 24. When the deviation ΔP is a positive value, the coating head 5 is moved back away from the backing roll 6, and conversely, the deviation When ΔP is a negative value, the coating head 5 is advanced so as to approach the backing roll 6 and the gap G is adjusted by the change amount Gc.

1 shows an embodiment of a coating apparatus according to the present invention, and is a front view of a coating state shown in a skeleton manner. FIG. The embodiment is shown, showing a coating head and a backing roll of the coating apparatus main body, wherein (A) is a plan view showing the backing roll with a two-dot chain line, and (B) is an enlarged view. FIG. The timing chart which shows the same embodiment, shows the period which the hydraulic pressure detector is detecting, and the state which the time zone setting device sets the standby time zone A and the control time zone B alternately It is.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Coating apparatus, 4 ... Control apparatus, 3 ... Liquid supply apparatus, 5 ... Coating head, 6 ... Backing roll, 16, 17, 18 ... Liquid stop wall, 14 ... Liquid storage chamber, 15 ... Measuring tool, 32 ... liquid pressure detector, A ... standby time zone, B ... control time zone, G ... gap, Gc ... set change amount, M ... coating liquid, Ps ... required value, ΔP ... deviation, R ... web transport path ,

Claims (2)

A backing roll that rotates by forming a web conveyance path on the outer peripheral surface, and a liquid reservoir chamber surrounded by a liquid stop wall and a measuring instrument facing the web conveyance path of the backing roll are extended in the transverse direction of the web conveyance path. The coating head includes a coating head, a liquid supply device that pumps the coating liquid to the liquid storage chamber, and a control device that adjusts the gap between the backing roll and the measuring instrument by moving the coating head toward and away from the backing roll. In the construction apparatus, the control device includes a fluid pressure detector that periodically measures the fluid pressure of the coating liquid with a detection cycle shorter than the length of a waiting time zone to be described later, and for each detection cycle of the fluid pressure detector. The time determined at a rate inversely proportional to the absolute value of the deviation obtained by subtracting the required value set as the liquid pressure of the coating liquid necessary to obtain a coating film of a predetermined thickness from the detected value detected in And based on the shortest time during which the gap can be adjusted. A waiting time period in which the gap is not adjusted by a predetermined time when the absolute value of the deviation is zero, or by a time obtained by dividing the required value by the absolute value of the deviation for a time longer than the reference time. And a control time zone in which the gap is adjusted by a set change amount are alternately and repeatedly controlled. In the control time zone, the coating head is moved forward and backward to reduce the absolute value of the deviation. A coating apparatus characterized by adjusting the gap.   The coating apparatus according to claim 1, wherein the change amount set in the control time zone is set to zero when the absolute value of the deviation is zero, and is increased at a rate proportional to the magnitude of the absolute value of the deviation.

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