Coating equipment

Abstract

To provide a coating apparatus that can suppress dripping during coating. [Solution] The coating apparatus according to the present invention comprises a tank for storing coating material, a die for discharging coating material, a first pipe connecting the die and the tank, a second pipe connecting a branch point P provided in the first pipe and the tank, a coating valve disposed between the branch point and the die, a circulation valve disposed in the second pipe, a pump disposed in the first pipe between the branch point and the tank, and a suck-back valve disposed between the die and the coating valve. Both the coating valve and the circulation valve comprise a valve body having a pair of opposing openings on its sides, and a substantially cylindrical rotary valve housed in the valve body with a through hole that penetrates radially. The rotary valve is in an open state when both ends of the through hole overlap with the openings, and in a closed state when both ends of the through hole do not overlap with the openings. Multiple through holes are formed radially in the rotary valve of the coating valve.

Description

Technical Field

[0001] The present invention relates to a coating device.

Background Art

[0002] A method of forming a coating film using a die is known. Patent Document 1 discloses a coating device capable of adjusting the end shape of a coating film by driving a sack-back valve disposed between the die and the coating valve to draw the coating material toward the sack-back valve side.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the coating device described in Patent Document 1, the coating liquid is supplied to the die by opening the coating valve, and the supply of the coating liquid is stopped by closing the coating valve. Therefore, by repeatedly opening and closing the coating valve, a coating film can be intermittently formed. However, if the time taken for opening and closing the coating valve is long, the dripping of the coating material deteriorates, and liquid dripping may occur.

[0005] The present invention has been made in view of such circumstances, and provides a coating device capable of suppressing liquid dripping during coating film formation.

Means for Solving the Problems

[0006] The coating apparatus according to the present invention comprises a tank for storing a coating material, a die for discharging the coating material, a first pipe connecting the die and the tank, a second pipe connecting a branching point provided in the first pipe and the tank, a coating valve disposed between the branching point and the die, a circulation valve disposed in the second pipe, a pump disposed in the first pipe between the branching point and the tank, and a suck-back valve disposed between the die and the coating valve. Both the coating valve and the circulation valve comprise a valve body having a pair of opposing openings on its side, and a substantially cylindrical rotary valve housed in the valve body and having a through hole that penetrates radially. The rotary valve is in an open state when both ends of the through hole overlap with the openings, and in a closed state when both ends of the through hole do not overlap with the openings. The rotary valve of the coating valve has a plurality of through holes formed radially. [Effects of the Invention]

[0007] The present invention provides a coating apparatus that can suppress dripping during coating. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram shows the configuration of the coating apparatus according to this embodiment. [Figure 2] This is a cross-sectional view of the coating valve according to this embodiment in the open state. [Figure 3] This is a cross-sectional view of the coating valve according to this embodiment in the closed state. [Figure 4] This is a perspective view of the rotary valve of the coating valve according to this embodiment. [Modes for carrying out the invention]

[0009] Specific embodiments to which the present invention is applied will be described in detail below with reference to the drawings. For clarity, the following description and drawings have been simplified as appropriate. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and redundant explanations are omitted as necessary for clarity. Furthermore, the right-handed xyz coordinate system shown in Figure 2 and the other figures is for explaining the positional relationships of the components, and typically the positive z-axis direction is vertically upward.

[0010] Figure 1 shows the configuration of a coating apparatus 1 according to this embodiment. As shown in Figure 1, the coating apparatus 1 includes a tank 11 for storing coating material, a die 12 for discharging coating material, a first pipe 13 connecting the die 12 and the tank 11, a second pipe 14 connecting a branching point P provided in the first pipe 13 and the tank 11, a coating valve 15 positioned between the branching point P and the die 12, a circulation valve 16 positioned in the second pipe 14, a pump 17 positioned between the branching point P and the tank 11 in the first pipe 13, and a suck-back valve 18 positioned between the die 12 and the coating valve 15. In Figure 1, the operating directions of the coating valve 15, the circulation valve 16, and the suck-back valve 18, as well as the flow path of the coating material during coating, are indicated by arrows.

[0011] Tank 11 stores the fluid coating material to be discharged from the die 12. The coating material stored in Tank 11 flows out through the first pipe 13 by the operation of Pump 17. As will be described later, the coating material flows from Tank 11 through the first pipe 13 by the operation of Pump 17 to the branching point P of the first pipe 13 and the second pipe 14. When the die 12 is in a discharge state, the coating material flows through the first pipe 13 towards the die 12. On the other hand, when the die 12 is not in a discharge state, the coating material flows through the second pipe 14 and returns to Tank 11.

[0012] The die 12 is a discharge section for coating material, with a tapered tip. In the example shown in Figure 1, the die 12 has a manifold 121, and a first pipe 13 is connected to the rear end of the manifold 121. For example, the tip of the die 12 is positioned to face the film 92 being conveyed by a backup roll 91 that rotates in the direction of the arrow. The die 12 discharges the coating material that has flowed in through the first pipe 13 from its tip side, forming a coating film 93 on the film 92 at a position facing the tip of the die 12. Note that the die 12 may also have a structure without a manifold 121.

[0013] The first pipe 13 connects the tank 11 and the die 12. Coating material flows through the first pipe 13. Along the path of the coating material in the first pipe 13, a suck-back valve 18, a coating valve 15, and a pump 17 are arranged in that order from the side where the die 12 is located. A branching point P to the second pipe 14 is provided between the coating valve 15 and the pump 17. The first pipe 13 has a larger diameter at the location where the suck-back valve 18 is installed, allowing the suck-back valve 18 to move radially while inserted into the first pipe 13. In the discharge state, the coating valve 15 is open, and the coating material discharged from the tank 11 and reaching the branching point P flows towards the die 12. On the other hand, in the circulation state, the coating valve 15 is closed, and the coating material does not flow from the branching point P towards the die 12.

[0014] One end of the second pipe 14 is connected to the coating valve 15 and pump 17 of the first pipe 13, and the other end is connected to the tank 11. A circulation valve 16 is also located along the path of the coating material flowing through the second pipe 14. When the coating material is being discharged from the die 12, the circulation valve 16 is closed, preventing the coating material from flowing through the second pipe 14. When the circulation valve 16 is open, the coating material returns to the tank 11 from the branching point P through the second pipe 14, creating a circulating state.

[0015] The coating valve 15 is a valve whose valve opens and closes when it rotates using power generated by the first motor 21. The first motor 21 receives power from, for example, an external power source (not shown) to generate the rotational force necessary to rotate the coating valve 15. The detailed structure of the coating valve 15 will be described later.

[0016] The circulation valve 16 is a valve whose valve opens and closes when it rotates using power generated by the second motor 22. The second motor 22 receives power from, for example, an external power source (not shown) to generate the rotational force necessary to rotate the circulation valve 16. The detailed structure of the circulation valve 16 will be described later.

[0017] Pump 17 is located in the first piping 13. Typically, pump 17 is located near the tank 11, and when pump 17 operates, it discharges the coating material from the tank 11 into the first piping 13.

[0018] The suck-back valve 18 is a roughly cylindrical piston and is inserted into the first pipe 13 from the outer diameter side toward the inside. A third motor 23 is connected to the suck-back valve 18. The suck-back valve 18 is driven by power received from the third motor 23 to move from the outside to the inside (pushing) or from the inside to the outside (pulling) of the first pipe 13. When the suck-back valve 18 is driven in the pushing direction, the suck-back valve 18 enters the first pipe 13, causing a rapid increase in the flow rate of the coating material discharged from the die 12. On the other hand, when the suck-back valve 18 is driven in the pulling direction, the flow rate of the coating material is rapidly reduced. The third motor 23 receives power from, for example, an external power source (not shown) and generates force to cause the suck-back valve 18 to perform pushing and pulling operations.

[0019] Next, we will explain the operation of the coating device 1 at the start of coating and at the end of coating. First, we will explain the start of coating.

[0020] First, in the initial state, the coating valve 15 is in the closed state and the circulation valve 16 is in the open state. At this time, the coating material discharged from the tank 11 to the first pipe 13 by the operation of the pump 17 passes through the second pipe 14 provided with the circulation valve 16 from the branch point P and returns to the tank 11. The suck-back valve 18 is in the retracted state.

[0021] Next, by operating the second motor 22, the circulation valve 16 rotates to the closed state. Since the pump 17 is operating here, the coating material is in a pressurized state near the branch point P.

[0022] Next, by operating the first motor 21, the coating valve 15 rotates to the open state. As a result, the coating material flows from the branch point P through the coating valve 15 toward the die 12.

[0023] [[ID=?]]Next, by operating the third motor 23, the suck-back valve 18 is put into the pushed-in state. As a result, the flow rate of the coating material discharged from the die 12 rapidly increases.

[0024] Next, the end of coating will be described. First, in the initial state, the coating valve 15 is in the open state, the circulation valve 16 is in the closed state, and further, the suck-back valve 18 is in the pushed-in state. At this time, the coating material discharged from the tank 11 to the first pipe 13 by the operation of the pump 17 is in the state of being discharged from the die 12.

[0025] Next, by operating the first motor 21, the coating valve 15 is rotated to the closed state. In other words, the coating valve 15 is closed while the coating material is being discharged from the die 12. Further, by operating the second motor 22, the circulation valve 16 is rotated to the open state. As a result, the coating material passes through the second pipe 14 provided with the circulation valve 16 from the branch point P and returns to the tank 11.

[0026] It seems there is a typo in the original text where "" should be "". The translation above has been adjusted accordingly.Next, the third motor 23 is operated to retract the suck-back valve 18. This causes the coating material to be retracted between the die 12 and the coating valve 15 in the first piping 13. Therefore, the coating process can be completed with the die 12 and the coating material in its vicinity retracted toward the vicinity of the suck-back valve 18. The final state at the end of the coating process is the same as the initial state at the start of the coating process.

[0027] Here, the detailed structure of the coating valve 15 will be explained using Figures 2 to 4. Figure 2 is a cross-sectional view of the coating valve 15 in the open state. Figure 3 is a cross-sectional view of the coating valve 15 in the closed state. As shown in Figures 2 and 3, the coating valve 15 comprises a valve body 151 having a pair of opposing openings 151a on its side, and a substantially cylindrical rotary valve 152 housed in the valve body 151 and having a through hole 152a that penetrates radially. Figure 4 is a perspective view of the rotary valve 152. As shown in Figure 4, in addition to the through hole 152a, the rotary valve 152 may also have a rotating shaft 152b provided to protrude along the central axis of the rotary valve 152. The rotary valve 152 rotates when the rotating shaft 152b is connected to the first motor 21.

[0028] As shown in Figures 2 and 3, the coating valve 15 is in an open state when both ends of the through-hole 152a of the rotary valve 152 overlap with the opening 151a, and in a closed state when both ends of the through-hole 152a do not overlap with the opening 151a. The rotary valve 152 of the coating valve 15 has multiple through-holes 152a formed radially. In the example in Figures 2 and 3, the rotary valve 152 has three through-holes 152a. Thus, a coating valve 15 in which the rotary valve 152 has multiple through-holes 152a can switch between open and closed with a smaller rotation angle compared to, for example, a structure with only one through-hole. Therefore, the opening and closing of the coating valve 15 can be switched at high speed, which can suppress dripping during coating.

[0029] The number of through holes 152a in the coating valve 15 is preferably 2 to 16, and more preferably 2 to 8. By providing a large number of through holes 152a, the opening and closing of the coating valve 15 can be switched at a faster speed. On the other hand, if there are too many through holes 152a, the cross-sectional area of ​​the through holes 152a becomes small, and the flow rate of coating material that can pass through the coating valve 15 becomes small.

[0030] Furthermore, it is preferable that the cross-sectional shape of the through-hole 152a of the coating valve 15 be approximately rectangular. That is, it is preferable that each through-hole 152a be approximately rectangular prism-shaped. By making the cross-section of the through-hole 152a approximately rectangular, the cross-sectional area of ​​the through-hole 152a can be designed to be larger, and the flow rate of coating material that can pass through the coating valve 15 can be increased. Therefore, the coating device 1 can efficiently discharge the coating material.

[0031] Next, the detailed structure of the circulation valve 16 will be described. Like the coating valve 15, the circulation valve 16 comprises a valve body having a pair of opposing openings on its sides, and a substantially cylindrical rotary valve housed in the valve body and having a through hole that penetrates radially. The circulation valve 16 is in an open state when both ends of the through hole of the rotary valve overlap with the openings, and in a closed state when both ends of the through hole do not overlap with the openings.

[0032] Similar to the coating valve 15, it is preferable that the rotary valve of the circulation valve 16 also has the same number of through holes arranged radially as the coating valve 15. In other words, it is preferable that the circulation valve 16 has the same structure as the coating valve 15, as shown in Figures 2 to 4. Since the circulation valve 16 having such a configuration has the same opening and closing speed as the coating valve 15, intermittent coating can be performed at high speed.

[0033] Furthermore, if the rotary valves of the coating valve 15 and the circulation valve 16 both have the same number of through holes arranged radially, it is preferable that the coating valve 15 and the circulation valve 16 are interlocked so that when one is closed, the other is open. In such a configuration, since both the coating valve 15 and the circulation valve 16 operate in a way that prevents them from being closed, the coating material is less likely to be pressurized near the branching point P. Therefore, the load on the first piping 13 is reduced, and the durability of the coating apparatus 1 is increased.

[0034] Although the present invention has been described in accordance with specific embodiments, it is not limited to the embodiments described above. The present invention is not limited to the embodiments described above and can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0035] 1 Coating apparatus 11 tanks 12 dives 121 Manifold 13. First Piping 14. Second Piping 15 Coated Valves 151 Valve box 151a opening 152 Rotary valve 152a Through hole 152b Rotation axis 16 Circulation valve 17 Pumps 18 Suckback Valve 21 First motor 22 Second motor 23 Third Motor 91 Backup Role 92 film 93 Coating film P Branch Point

Claims

1. A tank for storing coating materials, A die for dispensing the coating material, A first pipe connecting the die and the tank, A second pipe connects the branching point provided in the first pipe to the tank, A coating valve is positioned between the aforementioned branching point and the aforementioned die, A circulation valve located in the second piping, A pump located between the branching point and the tank in the first piping, The system includes a suck-back valve positioned between the die and the coating valve, Both the coating valve and the circulation valve comprise a valve body having a pair of opposing openings on its side, and a substantially cylindrical rotary valve housed in the valve body and having a through hole extending radially through it. The rotary valve is in an open state when both ends of the through hole overlap with the openings, and in a closed state when both ends of the through hole do not overlap with the openings. The rotary valve of the coating valve has multiple through holes arranged radially. Coating equipment.

2. The rotary valve of the circulation valve also has the same number of through holes arranged radially as the coating valve. The coating apparatus according to claim 1.

3. The coating valve and the circulation valve are interlocked such that when one is closed, the other is open. The coating apparatus according to claim 2.

4. The number of through holes in the coating valve is 2 to 16. The coating apparatus according to claim 1.

5. The cross-sectional shape of the through-hole of the coating valve is approximately rectangular. The coating apparatus according to claim 1.

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