JPS6171862A - Knife coater type continuous coating apparatus - Google Patents

Abstract

PURPOSE:To make the thickness of a paint always constant in an axial direction, by detecting the flexure of a pick-up roll and bending at least one of the pick-up roll and a knife so as to allow both of them to approach to each other. CONSTITUTION:A laser irradiation apparatus 66 is run along a guide and an applicator roll 32 is irradiated with laser beam. Because the applicator 32 is formed in a uniform thickness, the flexure amount of a pick-up roll 28 can be known by detecting the thickness of the film 79 on the roll 32. Hereupon, a knife edge 64 is allowed to a advance through a DC servo motor 62 and the knife 30 is bent so as to allow the central part of the knife 30 to approach the pick-up roll 28. When the non-uniformity of the thickness of the film 79 is not same at both ends of the roll 32 in the axial direction, one of bearing boxes 48 is raised and fallen to make the thickness of the film uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a knife coater type continuous coating device equipped with a knife that keeps the thickness of the paint constant on a pick-up roll to which the paint is supplied.

[Background of the invention]

A knife coater type continuous coating apparatus for continuously applying paint to a steel plate, disclosed in Japanese Patent Application No. 110733/1980, is shown in FIG.

In FIG. 5, paint 12 in a paint tank 10 is sent to a pressure tank 20 by a pump 16 via a valve 18. Pressure tank 20 has pressure tank 2
An air pipe 22 is provided to pressurize the inside. The paint 12 in the breather dam 20 is sent to the filter 24 via the flow rate regulating valve 23, and after foreign matter is removed, the paint 12 is sent to the paint dam 2.
Sent to 6. The paint dam 26 is the pickup roll 2
It is used to temporarily store paint in order to apply it to 8.

The paint deposited on the pick-up roll 2B is made uniform in thickness by a knife 30 provided close to the pick-up roll 28, and then transferred onto the applicator roll 32. A steel plate 36 fed by a bank-up roll 34 comes into contact with the applicator roll 32, and paint is continuously applied to the steel plate 36 from the applicator roll 32. Incidentally, the reference numeral 38 shown in FIG. 5 is a paint receiver that receives the overflowing paint 70 from the paint dam 26.

In such a conventional coating device, as a method of controlling the gap between the pickup roll 28 and the knife 30 in order to keep the paint thickness on the pickup roll 2B constant, the knife 30 is directly connected to a hydraulic cylinder and a servo pulp. Methods are being taken to control the situation. However, this method
The slight movement of the hydraulic cylinder directly causes the pickup roll 2
8 and the knife 30, a very high performance servo pulp is required. Further, a paint dam 2 is provided between the pickup roll 28 and the knife 30.
Since pressurized paint is supplied from 6, as shown in FIG. 6, the pickup roll 28 and knife 30 are bent by the pressure of inserting the paint, and the gap between the pickup roll 28 and knife 30 changes in the axial direction. For this reason, there was a drawback that the thickness of the coating film on the steel plate 36 after drying was not constant in the width direction of the steel plate. Furthermore, conventional painting equipment does not have a device for non-contact measurement of the thickness of the paint adhering to the surface of the pickup roll 28, so the thickness of the paint cannot be measured until after the paint has dried. Even if the thickness deviates from the target value, it is difficult to perform online correction control.

The purpose of the present invention is to provide a knife coater type continuous coating device that can keep the coating constant.

[Summary of the invention]

The present invention detects the deflection of the pickup roll, and depending on the detected amount of deflection of the pickup roll, deflects at least one of the pickup roll and the knife so that the pickup roll and the knife approach each other. The paint thickness on the pick-up roll is made constant in the axial direction.

[Embodiments of the invention]

A preferred embodiment of the knife coater type continuous coating apparatus according to the present invention will be described in detail with reference to the accompanying drawings. Note that the same reference numerals are given to the parts corresponding to the parts explained in the prior art, and the explanation thereof will be omitted.

FIG. 1 is a front view showing the main parts of a knife coater type continuous coating apparatus according to the present invention. In FIG. 1, a lower moving table 42 and an upper moving table 44 are provided on the lower frame 40.
An upper frame 46 is fixed onto the movable table 44. A bearing box 48, which rotatably supports the pickup roll 28, is slidably attached to the lower side of the upper frame 46. This bearing box 4
8 is a hydraulic cylinder 50 provided on the upper moving frame 44
The wedge 52 is driven by the upper frame 46.
go up and down along the side of the

Above the bearing box 48, a holder 54 supporting the knife 30 is fixed to the upper frame 46.
A position detector 56 and a spring 58 are arranged between and the holder 54. Further, a bracket 60 is provided above the knife 30 on the upper frame 46, and a knife wedge 64 driven by a DC servo motor 62 and a laser irradiation device 66 are provided on this bracket 60.

The applicator roll 32 is rotatably supported by a bearing box 68 provided on the lower moving table 42. The lower moving table 42 is moved by a shift cylinder 70 and can move forward and backward relative to the backup roll 34.

Further, the upper moving table 44 can be moved by the upper frame shift device 72, so that the pickup roll 28 and the applicator roll 32 can be moved toward and away from each other. The knife wedge 64 is provided in contact with the upper central portion of the knife 30, as shown in FIG. Further, the laser irradiation device 66 is connected to the applicator roll 32 as shown in FIG.
The vehicle can run on a guide 74 provided parallel to the vehicle. Note that reference numerals 76 and 78 shown in FIG. 1 are hoses that guide pressure oil to the hydraulic cylinder 50 via a servo pulp (not shown).

The operation of the embodiment constructed as described above is as follows.

The shifting table 42 is moved to the left in FIG. 1 by the shift cylinder 70, and the applicator roll 32 is brought into contact with the backup roll 34 with a constant pressure. Next, the upper moving table 4 is moved by the upper frame shift device 72.
4 to the left in Fig. 1, and pick up roll 2.
B is brought into contact with the applicator roll 32 with constant pressure. At this time, the wedge 52 is actuated via the hydraulic cylinder 50 to raise and lower the bearing box 48, and the pickup roll 28 is moved so that the gap between the pickup roll 2B and the knife 30 becomes a predetermined value depending on the coating thickness. hold in proper position. The position of the pickup roll 28, that is, the position of the bearing box 48, is read by a position detector interposed between the bearing box 48 and the holder 54, and the pickup roll 28 is properly positioned. You can know whether it is in the position or not. Note that the bearing box 48 has a spring 5 interposed between the bearing box 4B and the holder 54.
8, the bearing box 48 is forced downwardly so that when the wedge 52 retreats, the bearing box 48 quickly descends.

The wedge 52 is provided in each of the bearing boxes 48A and 48B that support both ends of the pickup roll 28.
By moving the rollers 2 forward and backward, the gap between the pickup roll 28 and the knife 30 can be freely changed, and the balance between the pickup roll 28 and the knife 30 can be obtained. The gap between the pick-up roll 28 and the knife 30 is, for example, about 30 μm when the coating thickness after drying on a steel plate is 10 μm. However, pickup roll 28 and knife 3
Even if the gap between 0 and 0 is maintained in equilibrium in the initial state, the paint supplied from the paint dam 26 shown in FIG. 5 is generally pressurized to about 1 to 2 Kp/crl As shown in FIG. 6, the pickup 2B and knife 30 are bent outwardly relative to the paint dam 26. For this reason, the pickup roll 28 and knife 30
The gap between the pick-up roll 28 is large at the center and narrow at both ends, making it impossible to keep the thickness of the paint on the pickup roll 28 constant. Moreover, since the amount of deflection between the pickup roll 28 and the knife 30 is not constant due to the effects of paint viscosity, paint temperature, etc., a pickup roll or knife with a crown on the tip is used from the beginning. However, it is not possible to precisely control the coating thickness.

Therefore, as shown in FIG. 3, the laser irradiation device 66 is run along the guide 74 to irradiate the applicator roll 32 with laser light, and the thickness of the coating film 79 on the applicator roll 32 is detected. The amount of deflection of the pickup roll 28 is determined, and the knife 30 is deflected via the knife wedge 64 to make the thickness of the coating film uniform. That is, the applicator roll 32 is formed to have a uniform thickness, and by measuring the thickness of the coating film 79 on the applicator roll 32, the amount of deflection of the pickup roll 2B can be determined. The laser irradiation device 66 receives the laser beam reflected from above the applicator roll 32, and as shown in FIG. The distance to the applicator roll 32 and the coating film 79 on the applicator roll 32 is calculated, and the thickness of the coating film 79 on the applicator roll 32 is calculated.

The distance calculation device BO sequentially inputs the determined thickness of the coating film 79 on the applicator roll 32 to the central control device 82.

The central control device 82 compares the thickness of the coating film inputted from the distance calculation device 80 with a target value inputted in advance,
It is determined whether the detected coating film thickness matches the target value and whether the thickness is uniform. When the central controller 82 detects that the thickness of the coating film 79 on the applicator roll 32 is not uniform and that the pickup roll 2B is deflected as described above, the central controller 82 controls the Knife wedge 64? advance. The rotational force of the DC servo motor 62 is converted into an axial force by the ball screw 84, which moves the knife wedge 64 forward so that the center of the knife 30 approaches the pick-up roll 28. to deflect. Note that when the central controller 82 detects that the thickness of the coating film 79 on the applicator roll 32 is not the same at both ends of the applicator roll 32 in the axial direction, the central controller 82 operates the servo pulp 86 to remove water from the pump P. The pressure oil sent to the hydraulic cylinder 50
The wedge 52 of either one of the bearing boxes 48A and 48B supporting the pickup roll 28 is moved back and forth to raise and lower the bearing box, so that the thickness of the coating film 79 on the applicator roll 32 becomes uniform. Do it like this.

By doing so, the coating film thickness can be continuously measured not only in the axial direction of the roller but also in the longitudinal direction of the steel plate, and the coating film thickness can be controlled with high precision.

In the above embodiment, the case where there is only one knife wedge 64 has been described, but by providing a plurality of knife wedges 64 and bending the knife 30, the coating film thickness can be controlled with high accuracy. . Further, it is also possible to provide hydraulic cylinders at both ends of the knife 300, apply bending force to the sinier 30 by the force of the hydraulic cylinders, and bend the sinier 30 by the bending force. Further, a hydraulic cylinder is provided outside the bearing boxes 48A and 48B of the pickup roll 28, and the pickup roll 28 is bent in the same way as the knife 30.
It is also possible to control the widthwise gap between 8 and knife 30.

〔Effect of the invention〕

As explained above, according to the present invention, the thickness of the paint that adheres to the pickup roll in the axial direction of the pickup roll can be made constant.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the main parts of an embodiment of the knife coater type continuous coating device according to the present invention, Fig. 2 is an explanatory diagram showing an example of the mounting position of the knife wedge for bending the knife, and Fig. 3 is an explanatory diagram showing an example of the mounting position of the knife wedge for bending the knife. An explanatory diagram of the method for measuring the coating film thickness on a roll, Fig. 4 is a block diagram of the method for controlling the coating film thickness using the knife coater type continuous coating device according to the present invention, and Fig. 5 shows the conventional knife coater type continuous coating. FIG. 6, which is a schematic configuration diagram of the apparatus, is a diagram showing the deflection of the pickup roll and the knife. 20...Pressure tank, 26...Paint dam, 2
8...Pickup roll, 30...Knife, 32
... Applicator roll, 34... Backup meal, 36... Steel plate, 62... DC servo motor,
64... Knife wedge, 66... Laser irradiation device, 79... Paint film, 80... Distance calculation device, 82...
・Central control device.

Claims (1)

[Claims] 1. A rotationally driven pickup roll, a knife provided near the pickup roll, and a paint supply device that pressurizes and supplies paint between the knife and the pickup roll. , a knife coater type continuous coating apparatus having an applicator roll that contacts an object to be coated and the pickup roll and applies the paint on the pickup roll to the object to be coated, a deflection detector that detects deflection of the pickup roll; A knife coater type continuous coating apparatus, comprising: a bending device that deflects at least one of the pickup roll and the knife in a direction toward each other based on a detection signal of the deflection detector. 2. The knife coater type continuous coating apparatus according to claim 1, wherein the deflection detection device is an infrared film thickness detector that detects the coating thickness on the applicator roll. 3. The bending device comprises a wedge disposed in contact with the knife on the opposite side of the knife from the pickup roll, and a cylinder for moving the wedge forward and backward. The knife coater type continuous coating device according to item 2. 4. The knife coater type continuous coating apparatus according to claim 1 or 2, wherein the bending device is a hydraulic cylinder provided at both ends of the knife or the pickup roll.