JPS6022984B2 - curtain coater - Google Patents

Description

[Detailed description of the invention] The present invention relates to a curtain coat outside.

The quality of the paint curtain formed by the coating head is
This is an important factor that determines the quality of coating on the object passing under the head.

For this reason, curtain coaters have been proposed that control various parameters related to the quality of paint curtains.
However, in addition to the quality of the paint curtain, various improvements have been made to conventional curtain coaters, such as automatic and instantaneous paint changes, reduction of costs and time associated with paint changes, and synchronization of the inlet and outlet conveyors. It is desirable to improve the coordination of various operations when replacing paint. Therefore, an object of the present invention is to provide a curtain coater and its system that can perform various operations associated with paint replacement virtually instantaneously.

Another object of the invention is an improvement in the conventional coating head.

The curtain coater according to the present invention includes a coating head, a coating head, an introduction conveyor for conveying the article to be coated below the coating head, a take-out conveyor for carrying the article to be coated from below the coating head, and an introduction conveyor for conveying the article to be coated from below the coating head. a space between the inlet conveyor and the outlet conveyor, in which the object to be coated is conveyed from the inlet conveyor to the outlet conveyor, a paint container, which collects the paint that has not been applied onto the object to be coated; It includes a roller that receives paint that has not been applied to the object to be coated, and a doctor blade that removes the paint from the roller.

Further, according to the invention, the doctor blade, in addition to the above-mentioned paint removal position, covers the paint container to prevent the evaporation of volatile components from the paint and to prevent the paint from being contaminated by the surrounding environment. It can also be used as a lid for a paint container.

Furthermore, according to the present invention, when the paint falls onto the roller without falling onto the object to be coated, the roller is folded over the paint roller to take in air and send froth into the paint container. .

The roller is rotating at sufficient speed. Furthermore, according to the invention, the inlet conveyor and the outlet conveyor each have their own conveyance mechanism.

For example, this unique conveyance mechanism may be a belt, but if the object to be coated is a light sheet or something like a paper box and is to be painted during a hotmelt process, it may be necessary to introduce The transport mechanism uses a pair of pinch rollers placed in close proximity, while the lead-out transport mechanism uses
In order to hold the object to be coated on the conveyor, a vacuum holding means or an air blow holding means is used. Further, according to the present invention, the coating head, the paint container, and the doctor blade are assembled as a set (hereinafter, assembled as a set will be referred to as an assembly for simplicity).
, supported by a conveying means (carriage) and held in a coating position with respect to inlet and outlet conveyors, etc., and can be quickly replaced with another assembly of similar construction when changing the paint.

That is, the second assembly has a separate coating head, paint container, doctor blade, is supported on the same carriage as the first assembly, and is connected to the first assembly IJ.
is removed from the painting position and at the same time the second assembly is moved into the painting position. In this case, the doctor blade of the first assembly moves away from the roller and becomes the lid of the paint container, and the doctor blade of the second assembly moves from being the lid of the paint container to a position where it abuts the roller. Further, according to the present invention, a speed control mechanism is provided for controlling the speeds of the inlet conveyor, the outlet conveyor, and the rollers provided therebetween.

This speed control mechanism includes a first hydraulic pump and a first hydraulic motor that drive the roller, a second hydraulic pump that drives a coating pump connected to the coating head, and a second hydraulic motor that drives the roller.
It includes a hydraulic motor, means for synchronously driving the first and second pumps, and means for driving the inlet and outlet conveyors to transport the workpieces at appropriate speeds. For example, the delivery conveyor drive means includes a hydraulic motor and means for controllably connecting the hydraulic motor and the first hydraulic motor to drive the delivery conveyor and the rollers.

The inlet conveyor drive means further includes an air clutch having a drive member and a driven member, means for applying a starting air signal to the clutch, means for synchronously connecting said drive village to the rollers, and said drive village. and means for synchronously connecting the inlet conveyor to the inlet conveyor. Additionally, the curtain coater of the present invention is provided with an improved device for sealing each end of the coating head.

This device makes it possible to deform a tube forming part of the coping head while maintaining a seal at the end of the tube. This end sealing device includes a piston having a support surface that slidably supports the end of the tube, and a cylinder that slidably accommodates the piston, and the piston has a cylinder-facing surface facing the cylinder. . The cylinder is attached to a support member, thus supporting the coating head in position. A paint inlet passage is provided in the piston and cylinder of one end seal, and a paint outlet passage is provided in the piston and syringe of the other end seal. Although the pressure of the paint applied to the supporting surface of the piston and the surface facing the cylinder is approximately equal, the area of the surface of the piston facing the cylinder is larger than the area of the supporting surface. Thus, the support surface typically presses and seals the end of the tube. By the way, below the paint introduction and outlet passages,
Paint tends to accumulate in areas surrounded by the sill and piston, and solid matter contained in the accumulated paint may settle. Therefore, in order to prevent such precipitation and coagulation, a paint passage is provided between the place where the paint accumulates and the end of the tube.
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The curtain coater system 20 shown in FIG.
It has an introduction conveyor 22 and an output conveyor 24.

There is a space 26 between the rear part 28 of the inlet conveyor 22 and the front part 30 of the outlet conveyor 24, and a loaf 32 for conveying the object to be coated is provided in this space 26. roller 3
2, it is possible to transport relatively small objects. The system 20 further includes a first coating head 34.
The head 34 is of the type disclosed in U.S. Pat. No. 4,075,976.

Container for collecting and storing paint (hereinafter simply referred to as paint container)
From 38, progressive cavity pump 4
0, the first paint is supplied to the coating head 34 through the three-way valve 42, the paint filter 44, and the inlet pipe 36 of the head 34.
supplied to The outlet line 46 of the first coating head 34 is connected to a bypass line 50 via a bypass valve 48 . Therefore, bypass valve 4
8 is open and the paint outflow orifice of the head 34 (
Alternatively, if the slit 52 is closed, the first paint returns to the paint container 38 through the bypass line 50. A front windshield screen 54 is arranged below a paint barrier trough 56 which is movable relative to the coating head 34 by means of a hydraulic cylinder 57 . On the other hand, a rear windshield screen 58 is suspended from the coating head 34. As shown simply in broken lines in FIG. 1, the above-described coating head 34 and the members connected thereto are mounted on a carriage 60.

Carriage 6, for example by hydraulic cylinder 61,
It is movable in the transport direction of the inlet and outlet conveyor sections 22, 24 and selectively moves the first coating head 34 onto the axis of rotation 62 of the roll 32 arranged in the space 26. The carriage 60 also supports a second coating head 64 that is spaced apart from the first coating head 34 and, when the first coating head 34 is in the use position, as shown in FIG. 2 coating head 64 is in a standby position. When the first coating head 34 is moved by the carriage 60 from the use position to the standby position, the second coating head 64 is also moved by the carriage 60 to the use position. With such a configuration, system 20 is capable of almost instantaneous paint changes. The carriage 60 transport mechanism includes a near bearing (not shown) that supports the carriage and a hydraulic cylinder 61 that changes the position of the coating heads 34,64. From the paint container 68, a progressive capacitance pump 70 and a three-way valve 72 are connected.
, paint filter 74 , inlet line 66 , and coating head 64 , a second paint is supplied to head 64 .

The outlet line 76 of the second coating head 64 is connected to the paint container 68 via a bypass valve 78 and a bypass line 80. Bypass valve 78 is opened to close paint outlet orifice 82 of second coating head 64 and circulate the second paint. This situation is the first
As shown in the figure. Adjacent to the second coating head 64 is a front windshield screen 84 attached to the bottom of a paint barrier gutter 86 . Since the gutter 86 is located below the orifice 82 when the orifice or slit 82 is closed by the hydraulic cylinder 87, it is possible to prevent the paint from falling onto the object passing under the head 64. Although this is not shown, the first coating head 3
The same applies to case 4. Note that a rear windshield screen 88 is arranged behind the second coating head 64. The paint containers 38, 68 are connected to the front walls 94, 9, respectively.
It has doctor blades 90 and 92 which are supported at 6.

The doctor blades 90 and 92 are controlled by hydraulic cylinders 97 and 99, respectively, and when the first copier saw head 34 is in the use position, the doctor blade 90 is
As shown in the figure, the paint on the roller is returned to the paint container 38 by contacting the roller 32. For example, contacting the doctor blade 90 with the chrome-plated roller 32 is for various purposes as described below.

First, as roller 32 rotates about axis 62 , it transfers paint from head 34 to doctor blade 90 . Doctor blade 90', roller 3
Since the paint is scraped off from the paint container 38 and returned to the paint container 38, it is economical. Furthermore, since the doctor blade 90 cleanly removes all the paint from the roller 32,
There is no need to clean the roller 32 again before replacing the paint. Furthermore, when the first coating head 34 is transferred to the standby position by the carriage 60, the doctor blade 90 is moved by the hydraulic cylinder 97 and closes the entrance portion 98 of the paint container 38, so that volatilization from the paint container 38 is removed. This can prevent components from escaping. Closing the paint container with a doctor blade also prevents the paint from being contaminated by airborne particles.
Similarly, the doctor blade 92 is attached to the front wall 9 of the paint container 68.
As shown in FIG. 1, when the second coating head 64 is in the standby position, the entrance part 100 of the container 68 is closed, while when the head 64 is in the use position
Although not shown, an unused second
The paint is scraped off and returned to the container 68.

Another advantage of roller 32 rotating about axis 62 is that
The unused paint is transported at a sufficient speed so that it does not fall onto the surface 102 of the roller 32, fold, and entrain air, thereby reducing paint froth.

The drive mechanism 110 for the chrome roll 32 includes a hydraulic motor 112 and a timing belt 114.

The other timing belt 116 is a chrome roll 32
The timing wheel 118 of the drive member 120 of the air clutch 122 is connected to the timing wheel 118 of the drive member 120 of the air clutch 122 . Air clutch 12
The second driven member 124 is directly connected to the drive roller 126 of the introduction conveyor 22 . Idler of introduction conveyor 22
Roller 128 is attached to the piston rod of pneumatic cylinder 130. Air is delivered from a compressed air source 132 to adjust the air pressure within the pneumatic cylinder 130 to adjust the tension in the belt 134 of the inlet conveyor 22. The output conveyor 24 is driven by a drive mechanism 140 that includes a hydraulic motor (HYDRA icmobr) 142 and a timing belt 144 that connects the output wheels of the hydraulic motor 142 and the drive rollers 148 of the output conveyor 24. It is hung on the timing wheel 146 of.

The outlet conveyor belt 150 is driven by drive rollers 148 and has three idler belts at the front of the outlet conveyor 24.
It is hung on a roller 152. The drive roller 148 is
Due to the attachment of the piston rod of pneumatic cylinder 154, pneumatic cylinder 154 is connected to a source of compressed air 156 to adjust the tension in conveyor belt 150. Static eliminator 16 adjacent to conveyor belt 134 and 15
0 is provided to remove static electricity generated in the belt and other parts, thereby minimizing the possibility of explosion of the system 20.

Such a static eliminator 160 is well known and is finally used since the paint is volatile and contains flammable substances. The three-way valves 42 and 72 are connected to the additional paint containers 162 and 1, respectively.
64 is selectively connected to a first coating system 166 and a second coating system 168 to apply the appropriate first and second coatings to the systems 166 and 1, respectively.
68. A timing wheel is attached to the output shaft of the hydraulic motor 170, and a belt 172 is looped around this wheel and the timing wheel attached to the shaft 176 of the pump 40.

With such a configuration, the rotor 17 attached to the shaft 176
Rotate 4. 180 of the second painting system is a hydraulic motor, 18
2 is a timing belt, 186 and 184 are the shaft and rotor of the pump 70, respectively, and the configuration is the first coating system 166.
This is the same as in the case of . FIG. 2 is a hydraulic circuit diagram of a hydraulic system that controls a portion of the apparatus shown in FIG.

Oil tank 200 included in hydraulic system 198 in FIG.
Hydraulic oil is supplied to the variable displacement pump 202 and the filter 21.
2 to the conduit 204. 206 is pump 2
02 is an input port, 208 is a suction pipe, and 210 is an output port of the pump 202.

An IJ leaf valve 214 is provided between the output boat and the return pipe 216 to the oil tank 200 to prevent the pump 202 from being destroyed due to excessive pressure. pump 20
2 is a wobble plate type variable displacement pump, which is controlled by a pneumatic signal applied from a pneumatic signal terminal 220 to an actuator 222 connected to a displacement controller 224. The capacity controller 224 is the pump 202
The amount of hydraulic oil per stroke of the pump is controlled by controlling the angle of the wobble plate. Hydraulic system 19
8 further includes another variable displacement pump 232, which is similar to the paint supply pump 40 shown in FIG.
Hydraulic oil is supplied to hydraulic pumps 170 and 180 that drive the hydraulic pumps 70, respectively.

The variable displacement pump 232 supplies hydraulic oil from the oil tank to the pipe line 234 via the filter 242 . The input boat 236 of the pump 232 is connected to the oil tank via a suction line 238 and the output boat 24
It is connected to the conduit 234 via a river filter 242. Return line 24 to output boat 240 and oil tank 200
A relief valve 244 is provided between the pumps 6 and 6 to prevent damage to the pump 232 due to excessive pressure within the pipe line 234. A pneumatic signal for controlling the amount of hydraulic oil discharged with each stroke of the pump 232 is applied from the pneumatic signal input terminal 250 to the actuator 252 to actuate the displacement controller 254 and control the amount of hydraulic oil from the pump 232. control. Note that, similarly to the pump 202, the capacity controller 254 is connected to the pump 232.
The amount of hydraulic oil discharged is controlled by controlling the angle of the wobble plate inside. Both pumps 202 and 232 are driven by an electric motor 260 with two output shafts, which is connected to an air-to-el converter.
It is driven by a pneumatic signal from a pneumatic signal terminal 262 via an ec interface 264.

Air Force converter 264 typically includes a pneumatically driven electrical switch connected to a solenoid that starts electric motor 260 . In the hydraulic system 198, the electric motor 260 and the pneumatic converter 264 are the only electrical components, so it can be said to be excellent in terms of image protection. The conduit 204 is
Conveyor mechanism control unit 2 via shirt off valve 270
74 , and the conduit 234 is connected to a paint control section 276 via a shirt-off valve 272 .

Note that both the control units 274 and 276 belong to the hydraulic system 198. Conveyor mechanism control section 274 includes a single pilot hydraulic control valve 280 connected to hydraulic motor 112 of roller 32 .

Control valve 280 has a pilot input boat 282 that is connected to pneumatic terminal 262 via pneumatic line 284 . When a pneumatic signal is present in line 284, hydraulic fluid flows from boat 286 to boat 288 and then from boats 290 to 292. This flow drives the hydraulic motor 112 of the roller 32. If there is no low pressure air signal in air line 284, control valve 280
is in the state shown in Figure 2, with boats 288 and 290
is closed, so boat 286 is directly connected to boat 292. A relief valve 294 is provided between boats 288 and 290 to protect hydraulic motor 112. Conveyor control section 274 further includes a single pilot type hydraulic control valve 300.

The pilot input signal to the control valve 300 is connected to the pneumatic terminal 30
1 to the pilot input boat 302 of the control valve 300 via pneumatic line 304. The presence of a low pressure air signal at pneumatic terminal 301 causes hydraulic fluid to flow from boat 306 to boat 308 and from boat 310 to boat 312 . This flow of hydraulic oil activates the hydraulic motor 142 that drives the delivery conveyor belt 150 (FIG. 1). Relief valve 314 protects hydraulic motor 142 from excessive pressure between boats 308 and 310. Hydraulic oil from boats 292 and 312 is supplied to shirt off valve 3.
20, returns to the oil tank 200 via a return pipe 322 and a filter 324. Another pneumatic terminal 326 controls an actuator 328 of the air clutch 122.

If low pressure air signal 326 is present and hydraulic motor 112 is driving roller 32 (FIG. 1), inlet conveyor drive roller 126 is also driven to move inlet conveyor belt 134. The paint control section 276 includes a hydraulic motor 1.
70 control unit 340 and hydraulic motor 180 control unit 3
There are 42. The control unit 34 has a double pilot type hydraulic control valve 344, and this control valve 344 has a "forward"
There is a pilot input boat 346 and a "reverse" pilot input boat 348. A low pressure "advance" air signal applied to pneumatic terminal 35 causes hydraulic fluid to flow into control valve 344.
from boat 352 to boat 354 and from boat 356 to boat 358. This allows the hydraulic motor 7
A flow of hydraulic oil in a first direction occurs within the paint container 38, and a first paint is pumped from the paint container 38 by the pump 40 (FIG. 1). Bypass valve 48 and coating head 3
The state of the paint outflow orifice (slit) 52 of No. 4 determines whether the first paint flows out from the orifice 52 or simply circulates within the closed circuit of the painting system. A low voltage electrical signal generated by the pneumatic terminal 36 of the "reverse" pneumatic signal is applied to the "reverse" pilot input boat 348 to direct hydraulic fluid from the control valve 344 from boat 352 to boat 356 and from boat 354 to the boat. Run to 358. by this,
The flow of hydraulic fluid in the hydraulic motor 170 will reverse and return the paint that was to be pumped from the pump 40 to the paint container 38. This has the advantage, for example, that the paint container 38 can be supplied directly from the additional paint container 162 via the three-way valve 42. Furthermore, between boats 354 and 356,
A leaf valve 361 is provided to protect the hydraulic motor 170. The control 342 of the hydraulic motor 180 includes a double pilot valve 364 having a "forward" pilot input boat 366 and a "reverse" pilot input boat 368.

A low pressure air signal applied to pneumatic terminal 37 is applied to "forward" pilot input boat 366 to flow hydraulic fluid from boat 372 to boat 374 and from boat 376 to boat 378. This causes a flow of hydraulic oil in the first direction within the hydraulic motor 180, which acts to cause the second paint to flow from the paint container 68 toward the pump 70.
As before, depending on the open or closed state of the bypass valve 78 and the paint outlet orifice 82, the second paint simply circulates within the closed circuit of the paint system, or the second paint flows through the second coating head 6.
It will be decided whether it will flow from 4. On the other hand, when a low pressure air signal is generated at the pneumatic terminal 380', this signal is transmitted to the control valve 364.
"Reverse" pilot input is applied to boat 368 to transfer hydraulic fluid from boat 372 to boat 376 and to boat 374.
from there to boat 378.

Accordingly, hydraulic oil flows into the hydraulic motor 180 in a second direction opposite to the first direction, reversing the operation of the pump 70, so that it flows from the additional paint container 164 to the three-way valve 72 and the pump 7.
The second paint is immediately supplied to the paint container 68 through the paint.
Note that a relief valve 381 is provided between the boats 374 and 376 to protect the hydraulic motor 180. FIG. 3 shows a hydraulic system having a pneumatic control section for controlling various operations of the curtain coater system 20. As shown in FIG.

The hydraulic system 371 in FIG. There are a controller 379 for controlling settings, a controller 383 for controlling the vertical position of the first coating head 34, and a controller 385 for controlling the vertical position of the second coating head 64. The pneumatically driven pump 384 is operated at high pressure (eg, 100.degree.
s. i. ), from the oil tank 386 to the high pressure pipe 388,
Supply a small amount of hydraulic oil. The control section 373 includes a double pilot valve 400 and a hydraulic cylinder 970, and the low pressure air signal generated at the terminal 404 is transmitted to the pilot input boat 406 of the valve 400 to direct hydraulic oil to the boats 408 to 410 of the valve 400, and Flow from boat 412 to 414.

This flow of hydraulic oil actuates the piston 416 of the hydraulic cylinder 970 to close the orifice 52. A low pressure air signal developed at terminal 418 is applied to pilot input boat 42 of valve 400 which causes hydraulic fluid to flow from boats 408 to 412 and from boats 410 to 414. Therefore, the operation of the piston 416 of the hydraulic cylinder 970 is reversed to open the orifice 52. The control section 375 of the hydraulic system 371 includes a double pilot valve 430 and a hydraulic cylinder 990.

A low pressure air signal developed at terminal 434 is applied to pilot input boat 436 of valve 430 to direct hydraulic fluid to boat 4.
38 to 440 and boats 442 to 444. This flow of hydraulic fluid actuates the piston 446 of the hydraulic syring 990 so that the orifice 82 closes. Meanwhile, a low pressure air signal developed at terminal 448 is applied to pilot input boat 450 of valve 430 to flow hydraulic fluid from boat 438 to 442 and from boat 440 to 444 in the direction of engagement of piston 446 of hydraulic sill 990. Open the orifice 82 by reversing it. A pressure reducing valve 452 is provided in the high pressure hydraulic line 388 and extends approximately one inch of the line 388.
00 Cape. s. i. The pressure of about 40 blood. s. i. lower to

The control section 377 of the orifice 52 of the hydraulic system 371 has a variable throttle 460 connected in series with a double pilot valve 462 and a hydraulic cylinder 464 .

The low pressure air signal present at terminal 466 is applied to pilot input port 468 of valve 462. In this case, hydraulic fluid flows from boats 470 to 472 of valve 462 and boat 4
It flows from 74 to 476. A low pressure air signal at terminal 478 is applied to pilot input port 48 of valve 462;
Hydraulic oil flows from boats 470 to 474 of valve 462 and from boats 472 to 476. In this way, terminal 466
The appearance of the signal causes the piston 48.2 in the hydraulic cylinder 464 to move in a first direction to open the orifice 52, while a signal is generated at the terminal 478. piston 482
is moved in the second direction to close the orifice 52. The connection between the hydraulic cylinder 464 and the first coating head 34 is shown in dashed lines in FIG. The use of control 377 eliminates the need for the manual crank and pinyon gears of the prior art. The same mechanism as described above applies to the second coating head 64.
The control unit 379 is provided with the control unit 379 of

The control section 379 includes a variable throttle 490, a double pilot valve 492, and a hydraulic cylinder 494. The low pressure air signal generated at the terminal belonging to the control section 379 is transmitted to the valve 49.
2 pilot input boats 498 and hydraulic oil flows from valve 492 boats 500 to 502 and from boats 504 to 506. The flow of hydraulic fluid in this direction causes the piston 515 in the hydraulic cylinder 494 to move into the first position.
and increases the set point of the orifice 82 of the second coating head 64. Meanwhile, a low pressure air signal developed at terminal 508 is applied to pilot input boat 510 of valve 492 to cause hydraulic fluid to flow from boats 500 to 504 and from boats 502 to 506. The flow of hydraulic oil in this direction causes the piston 512 to move into the hydraulic cylinder 49.
4 in a second direction to decrease the set point of orifice 82. The vertical position control section 383 of the first coating head 34 includes a double pilot valve 520, a pilot check valve 522, and two IJ leaf valves 524, 5.
It has 26. The control section 383 further includes hydraulic cylinders 528 and 530 connected to the ends 532 and 534 of the first coating head 34, respectively. The hydraulic cylinders 528 and 530 are attached to a carriage 60 (FIG. 1) and the coating head 3 on this carriage is mounted on the carriage 60 (FIG. 1).
Move 7 vertically. A low pressure air signal on terminal 536 is applied to pilot input port 538 of valve 520.

This signal causes hydraulic fluid to flow from boats 540 to 542 and from boats 544 to 546. This flow of hydraulic oil flows into the lower part of the hydraulic cylinder 528 via the pilot check valve 522. When the piston 548 rises, hydraulic oil flows into the hydraulic cylinder 53 from above the piston 548.
0 flows below the piston 550. piston 550
Hydraulic oil from above enters return line 552 of hydraulic system 371 via boats 544 and 546.
If the piston 548 reaches the top of the hydraulic cylinder 528 before the piston 550 reaches the top of the hydraulic cylinder 530, the relief valve 524 closes the hydraulic cylinder 528.
is removed from the hydraulic circuit and hydraulic oil flows directly into the cylinder below the piston 550. Piston 55, cylinder 53
It continues to rise until it reaches the top of 0, and when it reaches the top, the relief valve 526 also opens, separating the hydraulic cylinder 530 from the hydraulic circuit. Hydraulic fluid continues to flow from terminal 536 until the signal disappears, at which point valve 520 returns to the neutral position shown in FIG. First coating head 3
4, a low pressure air signal is introduced to terminal 554 and applied to pilot input port 556 of valve 520. Hydraulic fluid then flows from boats 540 to 544 and from boats 542 to 546. Check valve 522
The oil pressure at the pilot input boat 558 causes hydraulic oil to flow into the cylinder above the piston 550, from the cylinder below the piston 550 to the cylinder above the piston 548, and from below the piston 548 to the cylinder above the piston 52.
0 to return line 552. Hydraulic system 37
Vertical position control 38 of the second coating head 64 of 1
5 has a double pilot valve 560, a pilot check valve 562, and two relief valves 564, 566.

Note that, as described above, the relief valve 566 makes the heights of both ends of the second coating head 64 equal. The control unit 385 further includes a pair of hydraulic cylinders 568 connected to the ends 572, 574 of the second coating head 64.
,570. Hydraulic cylinders 568, 570 are attached to carriage 60 (FIG. 1) and move head 64 vertically thereon. The low pressure air signal presented at terminal 576 is connected to pilot input port 578 of valve 560.
is applied to

This signal causes hydraulic fluid to flow from boats 580 to 582 and from boats 584 to 586. This flow is directed to the piston 58 via the pilot check valve 562.
8 flows into the lower cylinder. When the piston 588 rises, hydraulic oil flows from above the piston 588 to the piston 59.
Flows below 0. Hydraulic oil from above piston 590 is routed to system 371 via boats 584 and 586.
Flows into return line 552 of. If the piston 588 reaches the top of the hydraulic cylinder 568 before the piston 590 reaches the top of the hydraulic cylinder 570, the relief valve 5
64 disconnects the hydraulic cylinder 568 from the hydraulic circuit and allows hydraulic fluid to flow to the cylinder below the piston 590.

The piston 59 continues to rise until it reaches the top of the hydraulic cylinder 570, at which point the relief valve 566 also opens, separating the hydraulic cylinder 570 from the hydraulic circuit.
Hydraulic fluid continues to flow from terminal 576 until the signal disappears, at which point valve 560 returns to the neutral position as shown in FIG. To lower the second coating head 64, a low pressure air signal is generated at terminal 594. This signal is connected to pilot input port 596 of valve 560.
, hydraulic fluid flows from boats 580 to 584 and from boats 582 to 586. Hydraulic pressure at pilot input boat 598 of check valve 562 causes hydraulic fluid to flow into the cylinder above piston 590 and from the cylinder below piston 588.
Hydraulic oil flows to the upper cylinder 568, and then the piston 5
Return line 55 from the lower cylinder 98 via valve 560
2. In FIG. 4, the first coating head 34
Alternatively, one end of the tube 600, which is the main part of the second coating head 64, is shown.

Although not shown, an assembly similar to that shown in FIG. 4 is present in the other section of tube 600 of heads 34 and 64. The end of the tube 600 is closed with a removable assembly 602 that seals the tube 600, which changes shape as the settings of the orifices (or slits) 52, 82 change.

Assembly 602 has an end flange 604 within which is a cylindrical portion 606 containing a piston 608 . A tapered portion 610 is disposed on the surface 612 side of the piston 608 and is fixed to the surface 612 by a screw 614 via a gasket 616. Gasket 616 is made of, for example, polytetrafluoroethylene (pol
ytetraf] made up of side roethyle ships). The piston 608 has a spring 618 and a bolt 62
0' is therefore biased toward the elastic tube 600. still,
The bolt 620 is inserted into a screw hole 624 provided in the flange 604. A washer 626 made of, for example, polytetrafluoroethylene is disposed between the head 628 of the bolt 620 and the flange 604 to seal the threaded portion. The flange 604 includes a bracket 63 that supports the coating head 34 or 64, and a set of nuts and studs 632 (actually, more than one set is used, but
Only one set is shown in Figure 4).

Gasket 616 abuts end 634 of tube 600;
The saddle portion is sealed by the urging force of the spring 618 and the pressure of the paint, which will be described later.

The narrower member 610 is a pipe (spacelingt).
Recessed within the recess 636 in the end 638 of the rib e) 640, the tube 640 is accurately positioned within the flexible tube 600 by means of the tapered member 61. tube 600
By disposing tube 640 therein, a gap is created between the interior sidewall of tube 600 and the exterior sidewall of tube 640 leading to paint exit orifice 52 or 82 below. tube 64
Paint overflowing from the gutter 646 formed at the top of the paint flows downward through the passage defined by the above-mentioned gap. 1st and 2nd
an inlet line 36 for each of the coating heads 34, 64;
Reference numerals 66 denote an opening 648 of the tapered member 610, a closing portion 650 of the gasket 616, and a closing portion 652 of the piston 608.
, and the entrance portion 654 of the cylinder 606.

Note that the Sekiguchi portions 648, 650, 652, and 654 are essentially Oka koji. A lip 656 is provided at the end of the tube 640;
abuts against a recess 658 provided in the tapered member 610;
Preventing the tube 640 from rotating about its axis, the gutter 6
46 is arranged in a straight line with the entrance portions 648, 650, 652, and 654. A conduit 647 extending from the filter 44 (FIG. 1) to the inlet conduit 36 is attached to the mounting member 66.
The fluid pressure of the paint applied to the assembly 602 by the
On the top, they are virtually equal. However, the effective area of surface 662 is somewhat larger than the effective area of gasket 616 in contact with the paint. Therefore, piston 608 and tube 60
Different forces are applied to the gasket 616 that seals the end of the 0. If there is no paint in the coating system, the biasing force of spring 618 is sufficient to keep assembly 602 biased against tube 60. However, as the pressure within tube 600 increases, the pressure differential across piston 608 increases, causing gasket 616 to more firmly abut the end of tube 600, creating a tighter seal. ○ in the groove of cylinder 606
A ring gasket 664 is arranged to improve the sealing effect between the piston 608 and the cylinder 606 and prevent paint from leaking from the cylinder.

As previously mentioned, although not shown, the other end of tube 600 is provided with a configuration similar to that shown in FIG. 4.

Of course, this configuration also applies to the first and second coating heads 3.
4 and 64 outlet lines 46 and 76, respectively. Further, a cavity (or paint reservoir) 66 formed by a surface 662 of the piston 608 and an adjacent surface of the sill 606
There are 6. However, if a paint with a relatively high solids content remains in one place, undesirable precipitation may occur. Such precipitation must be avoided in the cavity 666, and it is also necessary to prevent the paint from clumping within the cavity 666, as some paints tend to harden over time. For this purpose, a downwardly inclined passage 668 is provided in the piston 608. Furthermore, a passage 670 is provided in the gasket 616 to connect the cavity 666 and the orifice 5.
The pipe 600 adjacent to the pipe 2 communicates with the pipe 600 adjacent to the pipe 600. Paint leaks from the cavity 666 into the tube 600 through passages 668 and 670, thereby preventing the paint from stagnating, settling, or solidifying within the cavity 666. At the other end of tube 600 (not shown), passages corresponding to passages 668 and 670 are provided. Passages 668 and 67
The paint from zero can be used to drip down the curtain edge guide line 672 to reduce the differential rate of paint fall at and near the guide line 672. Therefore, the possibility of curtain breakage at the curtain edge can be reduced. The coating head is equipped with means for deforming the side wall of the elastic tube in order to selectively adjust the width of the orifice (or slit), and means for protecting the elastic tube in a desired bending direction. Detailed explanation has been omitted.
An air clutch 122 having a driving roller 126 (driving member) and a driven member 124 shown in FIG. 1, an air signal applying means having a pneumatic terminal 326 shown in FIG. a means of connecting to
The means for synchronously connecting the driven member 124 to the inlet conveyor 22 constitute selective drive means.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing a curtain coater according to the present invention, FIG. 2 is a hydraulic circuit showing a hydraulic system that controls the force-tens coater of the present invention, and FIG. 3 is a hydraulic system that controls the curtain coater of the present invention. FIG. 4 is a longitudinal cross-sectional view of the end of the coating head according to the present invention shown in FIG. 1; 22...Introduction conveyor, 24...Output conveyor, 32...
...rollers, 34, 36...first and second coating heads, 38,68, respectively...paint containers, 40,7
0... Progressing cavity pump (variable displacement pump), 90, 92... Doctor blade, 600... Elastic tube, 606... Cylinder, 608... Piston, 630...Support village, 666.
...Cavity (paint pool). Z Kobinore pre-urn cliff Z7 public bait

Claims (1)

[Scope of Claims] 1. A coating head, means for conveying the object to be coated under the coating head, a roller for receiving unused paint, a paint container for collecting unused paint, and a container for unused paint. means for rotating said roller at a sufficient speed to prevent the formation of froth; a first position for abutting said roller to remove and collect paint on said roller in said paint container; A curtain coater comprising: a doctor blade that can be changed to a second position for preventing volatile components of paint from escaping from a container; and means for placing the doctor blade in the first or second position. 2. The curtain coater further includes a delivery conveyor for conveying the object to be coated from below the coating head, and the roller receives unused paint or is involved in conveying the object to be coated. Curtain coater as described in section. 3 a coating head, an introduction conveyor that conveys the object to be coated below the coating head, and an outlet conveyor that conveys the object to be coated from below the coating head;
A space provided below the coating head and between the inlet and outlet conveyors, a paint container for storing unused paint, and a paint container placed in the space to receive unused paint or convey the object to be coated. a roller, means for rotating said roller at a sufficient speed to prevent froth formation in unused paint, and a first position abutting said roller to remove and collect paint on said roller in said paint container. a doctor blade movable to a second position for closing the paint container and preventing volatile components of the paint from escaping from the paint container; means for placing the doctor blade in the first or second position; and a drive member. and a driven member, means for applying a starting air signal to the air clutch, means for synchronously connecting the drive member to the roller, and synchronously connecting the driven member to a conveyor belt of the inlet conveyor. A curtain coater comprising: a means for connecting to a curtain coater; 4 a coating head, an introduction conveyor that conveys the object to be coated below the coating head, and an outlet conveyor that conveys the object to be coated from below the coating head;
A space provided below the coating head and between the inlet and outlet conveyors, a paint container for storing unused paint, and a paint container placed in the space to receive unused paint or convey the object to be coated. a roller, means for rotating said roller at a sufficient speed to prevent froth formation in unused paint, and a first position abutting said roller to remove and collect paint on said roller in said paint container. a doctor blade movable to a second position for closing the paint container and preventing volatile components of the paint from escaping from the paint container; and means for placing the doctor blade in the first or second position; The coating head, the paint container, and the doctor blade are supported as a set by a conveying means, and when replacing the paint, the coating head, the paint container, and the doctor blade having the same structure as the pair supported by the conveying means are used. A curtain coater characterized in that it is replaceable with another set of blades. 5 a coating head, an introduction conveyor that conveys the object to be coated below the coating head, and an outlet conveyor that conveys the object to be coated from below the coating head;
A space provided below the coating head and between the inlet and outlet conveyors, a paint container for storing unused paint, and a paint container placed in the space to receive unused paint or convey the object to be coated. a roller, means for rotating said roller at a sufficient speed to prevent froth formation in unused paint, and a first position abutting said roller to remove and collect paint on said roller in said paint container. a doctor blade movable to a second position for closing the paint container and preventing volatile components of the paint from escaping from the paint container; and means for placing the doctor blade in the first or second position; The curtain coater is characterized in that the coating head is adapted to allow the paint container to flow through the bypass line when the doctor blade is in the second position.