Coating device

Abstract

To reduce an amount of a coating material remaining outside a nozzle.SOLUTION: A coating device 1 includes a nozzle 2, an assist air jetting part 3, and a cut air jetting part 4. The assist air jetting part 3 jets assist air AA toward a coating material M from the rear of the nozzle 2 relative to a moving direction X of the nozzle 2. The cut air jetting part 4 jets cut air CA toward the coating material M from the rear of the nozzle 2 relative to the moving direction X of the nozzle 2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a coating device having a nozzle for discharging a coating material. [Background technology]

[0002] Generally, steel sheets with a thickness of approximately 0.55 mm to 0.7 mm are used for the exterior of automobiles. Furthermore, the exterior design is extremely important for the value of the product. If distortion occurs in this exterior during the steel sheet processing process or the vehicle production process, it can lead to a deterioration in appearance, vibrations when the doors are opened and closed, or contact between metal parts, which can lead to a deterioration in product quality and a loss of value.

[0003] For this reason, it is necessary to ensure the rigidity of the steel plate to prevent a decline in product quality. However, increasing the plate thickness to ensure rigidity can suppress distortion, but this can lead to a decrease in driving performance, such as a decrease in fuel efficiency due to the increased weight, and an increase in costs. To prevent this, partial reinforcement measures are taken, such as applying reinforcing material to parts of the steel plate.

[0004] For example, Patent Document 1 discloses an apparatus for applying a coating material (fluid material) such as a reinforcing material composed of a high viscosity liquid to a coating target such as a steel plate for an automobile. This coating apparatus includes a coating material supply device and a nozzle for discharging the coating material. The supply device includes a pump for supplying the coating material to the nozzle. The nozzle discharges the coating material supplied by the supply device in a band shape to apply it to the coating target (see paragraphs 0047 to 0049 of the same document).

[0005] The nozzle includes a discharge means, a fixing means, and a cutting means (see paragraph 0049 of the same document). The discharge means has a discharge port for discharging the coating material. The fixing means fixes the coating material to the coating object by blowing compressed gas onto the coating material discharged from the discharge port of the discharge means toward the coating object.

[0006] The cutting means is for cutting the coating material discharged from the discharge port of the discharge means, and may be a wire or compressed gas.

[0007] The cutting means using a wire includes a slide structure that movably holds the wire, and an air cylinder mechanism as a drive mechanism that moves the wire (see paragraphs 0064 to 0067 of the same document).

[0008] After the application of the coating material to the coating object is completed, the cutting means moves the wire in a predetermined direction by the action of the slide structure and drive mechanism, thereby directly cutting the coating material being discharged from the discharge outlet of the discharge means (see paragraphs 0075 and 0076 of the same document).

[0009] When compressed gas is used as the cutting means, the nozzle has a compressed gas flow path for the cutting means (cutting gas flow path) in addition to a compressed gas flow path for the fixing means (fixing gas flow path). The cutting gas flow path ejects compressed cutting gas vertically downward, and may cut the coating material applied to the coating target (see paragraph 0085 and Figure 13(a) of the same document). [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-139751 Summary of the Invention [Problem to be solved by the invention]

[0011] In conventional coating devices, when a wire is used as the cutting means, the coating material adheres to the wire after cutting. If the material adheres to the wire incompletely and adheres to an unintended part of the product, there is a concern that it may cause problems with assembly in subsequent processes. Furthermore, if the material is not sufficiently adhered and peels off during the coating process, it may cause rust and damage the value of the product. Furthermore, the structure required to move the wire is complex, which makes maintenance work more cumbersome and may lead to malfunctions.

[0012] On the other hand, if compressed gas is used as the cutting means, the above maintenance work can be omitted. However, if compressed gas is ejected downward to cut the coating material, and the coating material is highly viscous, a large amount of the coating material will remain hanging outside the discharge port of the discharge means after cutting.

[0013] If a large amount of coating material remains outside the discharge means in this way, there is a risk that the remaining material will adhere beyond the position where coating is desired to end (end point), or when coating the coating material at the next coating position, the coating material will adhere to a position before the position where coating is desired to begin (start point), or the coating thickness of the coating material at the start point will increase, making it impossible to coat the coating material with precision. Furthermore, if a large amount of coating material remains as described above, there is a concern that the remaining material will adhere insufficiently to the work surface outside the coating range and then peel off, which may cause rust in that area.

[0014] The present invention has been made in view of the above circumstances, and has as its technical object to reduce the amount of coating material remaining outside the nozzle and to improve the positional accuracy of the start point and end point. [Means for solving the problem]

[0015] The present invention has been made to solve the above-mentioned problems, and provides a coating device having a nozzle that moves in a predetermined direction while ejecting coating material downward, comprising: an assist air injection unit that injects assist air in a direction inclined relative to the axis of the coating material ejected from the nozzle; and a cut air injection unit that cuts the coating material by injecting cut air at a predetermined angle relative to the axis of the coating material ejected from the nozzle, wherein the assist air injection unit injects the assist air toward the coating material from behind the nozzle in the direction of movement of the nozzle, and the cut air injection unit injects the cut air toward the coating material from behind the nozzle in the direction of movement of the nozzle.

[0016] According to this configuration, by ejecting the cutting air for cutting the coating material at a predetermined angle relative to the axis of the coating material, the coating material can be cut at a higher position, i.e., closer to the nozzle, compared to conventional cases in which air is ejected vertically downward. This reduces the amount of coating material remaining outside the nozzle. This makes it possible to apply the coating material with high precision at the start and end points of the coating process. Furthermore, because the coating target is located on an extension of the ejection direction of the assist air, when the coating material is cut by the cut air, the coating material remaining between the nozzle and the coating target can be reliably adhered to the coating target by the assist air. [Effects of the Invention]

[0017] According to the present invention, the amount of coating material remaining on the outside of the nozzle can be reduced. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. [Figure 2] FIG. 2 is a front view of an assist air ejection portion and a cut air ejection portion. [Figure 3] FIG. 4 is an enlarged side view of a main part of a nozzle and a cutting air ejection part. DETAILED DESCRIPTION OF THE INVENTION

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Figures 1 and 3 show an embodiment of a coating device according to the present invention.

[0020] As shown in Figure 1, the coating device 1 includes a nozzle 2 that ejects coating material M, an assist air injection unit 3 that blows assist air AA toward the coating material M ejected from the nozzle 2, a cut air injection unit 4 that blows cut air CA toward the coating material M, and air supply units 5a and 5b that supply compressed air to the assist air injection unit 3 and the cut air injection unit 4.

[0021] The nozzle 2 is configured to be movable in the vertical and horizontal directions. In this embodiment, the nozzle 2 is configured to eject a highly viscous liquid coating material M while moving along a predetermined movement direction (for example, the horizontal direction) X. The nozzle 2 is connected to a pressure-feeding device (pump) (not shown), and can eject the coating material M by pushing it out, the coating material being pressure-fed by the pressure-fed device.

[0022] The nozzle 2 has an outlet 2a for discharging the coating material M. The outlet 2a faces downward and is configured to discharge the coating material M in a strip shape vertically downward. The outlet 2a is configured as a flat (e.g., rectangular) opening, but is not limited to this shape. The vertical distance H1 between the outlet 2a at the tip of the nozzle 2 and the coating target W is usually about 1 mm to 5 mm, including the target coating thickness and a margin, but is not limited to this range.

[0023] 1 and 2, the discharge port 2a has a first width D11 and a second width D12. The first width D11 is set smaller than the second width D12. As a result, the coating material M discharged from the discharge port 2a has a thickness T (see FIG. 1) that is the same as the first width D11 of the discharge port 2a. In addition, the coating material M discharged from the discharge port 2a has a width DM (see FIG. 2) that is the same as the second width D12 of the discharge port 2a.

[0024] The assist air jetting unit 3 is configured as one unit with the nozzle 2 and is configured to be movable together with the nozzle 2. The assist air jetting unit 3 is configured to jet assist air AA in a direction inclined with respect to the axis L1 of the coating material M discharged from the nozzle 2. In other words, the assist air jetting unit 3 jets assist air AA along a jetting direction inclined at a predetermined angle with respect to the direction of movement (horizontal direction) X. Note that, as shown in FIG. 1 , in this embodiment, the axis of the nozzle 2 coincides with the axis L1 of the coating material M applied from the nozzle 2.

[0025] The spray direction of the assist air AA from the assist air spraying unit 3 is preferably inclined, for example, in the range of 25° to 45° with respect to the direction of movement (horizontal direction). The spray direction of the assist air AA is not limited to the above angle range and can be set appropriately depending on the size of the coating target W, the coating area, etc.

[0026] 1, the assist air jetting unit 3 is disposed behind the nozzle 2 in the movement direction X of the nozzle 2. As a result, the assist air jetting unit 3 is configured to jet assist air AA from behind the nozzle 2 toward the coating material M while moving together with the nozzle 2.

[0027] The assist air ejection unit 3 has an ejection port 3a that ejects the assist air AA, and an air flow path 3b that sends the assist air AA to the ejection port 3a.

[0028] 2, the outlet 3a of the assist air ejection unit 3 is configured as a flat (e.g., rectangular) opening, but is not limited to this shape. The outlet 3a has a first width D21 and a second width D22. The first width D21 is set larger than the second width D22.

[0029] The ejection port 3a of the assist air ejection unit 3 is arranged so that the direction along the first width D21 coincides with the width direction (direction along the width DM) of the coating material M. As shown in FIG. 2, the first width D21 of the ejection port 3a is larger than the second width D12 of the nozzle 2. In other words, the first width D21 of the ejection port 3a is larger than the width DM of the coating material M ejected from the nozzle 2.

[0030] The nozzle 2 is disposed within the range of a first width D21 of the ejection port 3a in a front view. This allows the ejection port 3a to spray the assist air AA over the entire width DM of the coating material M ejected from the nozzle 2. The ejection port 3a blows the assist air AA toward the position where the coating material M ejected from the nozzle 2 comes into contact with the coating target W.

[0031] The air flow path 3b of the assist air ejection unit 3 is defined in a rectangular shape in cross section by a wall portion that constitutes this air flow path 3b. The air flow path 3b is connected to the air supply unit 5a.

[0032] The cutting air jetting unit 4 is configured as one unit with the nozzle 2 and is configured to be movable together with the nozzle 2. The cutting air jetting unit 4 is also configured as one unit with the assist air jetting unit 3 and is provided above the assist air jetting unit 3.

[0033] The cutting air jetting unit 4 is disposed behind the nozzle 2 in the movement direction X of the nozzle 2. As a result, the cutting air jetting unit 4 is configured to jet cutting air CA from behind the nozzle 2 toward the coating material M while moving together with the nozzle 2.

[0034] The cutting air jetting unit 4 is configured to cut the coating material M by jetting cutting air CA in a direction perpendicular to the axis L1 of the coating material M discharged from the nozzle 2, i.e., along the movement direction (horizontal direction) X of the nozzle 2. In this embodiment, the direction perpendicular to the axis L1 of the coating material M includes a direction inclined within a range of ±5° from this perpendicular direction. However, in this embodiment, the direction in which the cutting air jetting unit 4 jets the cutting air CA also includes a direction inclined at a predetermined angle from the axis L1 of the coating material M. Specifically, as shown in FIG. 3, the direction in which the cutting air CA is jetted may be inclined within an angle range of +θ to −θ with respect to the horizontal direction (the direction perpendicular to the axis L1 of the coating material M). The angle θ with respect to the horizontal direction is preferably 30° or less.

[0035] The cut air jetting section 4 has an ejection port 4a for ejecting the cut air CA, and an air flow path 4b for supplying the cut air CA to the ejection port 4a.

[0036] 1, the nozzle 4a of the cut air jetting unit 4 is located forward of the nozzle 3a of the assist air jetting unit 3. This allows the nozzle 4a to jet the cut air CA toward the coating material M without affecting the assist air AA jetted from the assist air jetting unit 3.

[0037] 2, the nozzle 4a of the cut air jet unit 4 is configured as a flat (e.g., rectangular) opening, but is not limited to this shape. The nozzle 4a has a first width D31 and a second width D32. The first width D31 is set larger than the second width D32.

[0038] 2, the first width D31 of the ejection port 4a in the cut air ejection unit 4 is larger than the second width D12 of the nozzle 2. In other words, the first width D31 of the ejection port 4a is larger than the width DM of the coating material M ejected from the nozzle 2.

[0039] The nozzle 2 is disposed within the range of the first width D31 of the ejection port 4a in a front view. This allows the ejection port 4a to spray the cutting air CA over the entire width DM of the coating material M ejected from the nozzle 2.

[0040] When cutting the coating material M discharged from the nozzle 2, the cutting air CA is sprayed onto the coating material M at a position directly below the discharge port 2a of the nozzle 2. When the cutting air CA is sprayed onto the coating material M, it is preferable that the spray position be set as close as possible to the discharge port 2a of the nozzle 2. Specifically, the vertical distance H2 (see FIG. 1) between the axis L2 of the discharge port 4a of the cutting air spraying unit 4 and the discharge port 2a of the nozzle 2 is preferably 0.5 mm or more and 5.5 mm or less, but is not limited to this range. The coating device 1 may also be provided with an adjustment mechanism for adjusting the distance H2 between the discharge port 4a and the discharge port 2a.

[0041] The air flow path 4b of the cutting air jetting unit 4 is defined in a rectangular shape in cross section by a wall portion that constitutes this air flow path 4b. The air flow path 4b is connected to an air supply unit 5b.

[0042] The air supply units 5a, 5b include a first air supply unit 5a that supplies compressed air to the assist air injection unit 3, and a second air supply unit 5b that supplies compressed air to the cut air injection unit 4. Each of the air supply units 5a, 5b is configured by, for example, a compressor, but the configuration of the air supply units 5a, 5b is not limited to this embodiment.

[0043] The first air supply unit 5a and the second air supply unit 5b are configured independently to supply compressed air to each air supply unit 5a, 5b individually. This allows the first air supply unit 5a to individually set the pressure and, in particular, the flow rate of the assist air AA. Furthermore, the second air supply unit 5b allows individually set the pressure and, in particular, the flow rate of the cut air CA. It is also possible to actively control the pressure or flow rate of the assist air AA or the cut air CA by using a single throttle or by controlling the compressed air with a control device. It is also possible to simultaneously spray the assist air AA and the cut air CA to improve the accuracy of the deposition position of the coating material M on the coating target W.

[0044] Hereinafter, a method for applying the coating material M to the coating target W using the coating device 1 having the above configuration will be described.

[0045] Examples of the coating target W include, but are not limited to, steel sheets for automobiles. Steel sheets for automobiles are used for exterior components such as outer door panels. Steel sheets are also used for interior surfaces of automobiles, such as floors. Steel sheets used for floors can transmit and amplify vibrations from the engine, drivetrain, and road surface. Therefore, by coating the steel sheet with coating material M, which acts not only as a reinforcing material but also as a vibration-damping material with a damping function, it becomes possible to efficiently suppress noise generation while minimizing the increase in vehicle weight.

[0046] The coating device 1 places the nozzle 2 above the coating target W. Then, the coating device 1 discharges the coating material M vertically downward from the discharge port 2a of the nozzle 2, and moves the nozzle 2 along the movement direction X from a coating start position (start point) to a coating end position (end point).

[0047] The assist air jetting unit 3 moves together with the nozzle 2 and jets assist air AA from the rear of the nozzle 2 toward the coating material M. The assist air AA comes into contact with the coating material M at the position where the coating material M comes into contact with the coating target W. As a result, the coating material M is coated over its entire surface in a state of close contact with the surface shape of the coating target W.

[0048] The cutting air jetting unit 4 moves together with the nozzle 2 without jetting cutting air CA while the nozzle 2 moves from the starting point to the ending point.

[0049] The coating device 1 activates the cutting air jetting unit 4 when the nozzle 2 moves to the end point or just before the nozzle 2 arrives at the end point. The cutting air jetting unit 4 jets cutting air CA from behind the nozzle 2. The cutting air CA comes into contact with the coating material M at a cutting position (the position where the coating material M intersects with the axis L2) set directly below the discharge port 2a of the nozzle 2, and cuts the coating material M by its pressure. The cutting air CA is preferably jetted instantaneously using compressed air with a higher pressure than the assist air AA.

[0050] According to the coating device 1 of this embodiment described above, by ejecting the cutting air CA for cutting the coating material M at a predetermined angle with respect to the axis L1 of the coating material M, it is possible to cut the coating material M at a higher position, i.e., at a position closer to the discharge port 2a, compared to conventional cases in which the cutting air is ejected vertically downward. This makes it possible to reduce the amount of coating material M remaining outside the discharge port 2a.

[0051] Furthermore, by using the cut air CA to cut the coating material M with high precision, the accuracy of the coating position (start point and end point) of the coating material M on the coating target W can be improved.

[0052] In this embodiment, by blowing assist air AA onto the coating material M, the coating material M can be applied to the surface of the coating target W with a uniform thickness. For example, when coating the coating material M over a width of approximately 100 mm, the coating target W may entrap air between itself and the coating material M, causing the material to adhere to the coating target W. This air may remain between the coating material M and the coating target W. The coating material M hardens during a subsequent coating baking process, during which the residual air expands. In this case, not only may the coating material W not perform as expected, but there is also a concern that the coating material W may rupture at the location of the residual air, causing parts to peel off, or that the peeled areas may become insufficiently painted, potentially resulting in rust. Furthermore, the coating target W has an uneven shape formed to ensure rigidity, avoid contact with other structures, attach parts, and so on. Even when coating the coating material M according to such an uneven shape, the blowing of assist air AA effectively prevents air from entering between the coating target W and the coating material M. Furthermore, since the thickness of the coating material M can be controlled to be uniform, it is also possible to make the thickness of the coating material M as thin as possible.

[0053] In this embodiment, the coating device 1 can be made as small as possible by integrally configuring the assist air jetting unit 3 and the cut air jetting unit 4 behind the nozzle 2. Furthermore, by arranging the assist air jetting unit 3 and the cut air jetting unit 4 behind the nozzle 2, space can be secured in front of the nozzle 2, and the position and attitude (angle) of the nozzle 2 can be adjusted to suit the application of the coating material M.

[0054] The present invention is not limited to the configuration of the above-described embodiment, nor is it limited to the above-described effects. The present invention can be modified in various ways without departing from the spirit of the present invention.

[0055] In the above embodiment, the coating device 1 is illustrated as having one nozzle 2, one assist air jetting unit 3, and one cut air jetting unit 4, but the present invention is not limited to this configuration. The coating device 1 may be equipped with a plurality of nozzles 2, a plurality of assist air jetting units 3, and a plurality of cut air jetting units 4. Furthermore, the numbers of nozzles 2, assist air jetting units 3, and cut air jetting units 4 may vary.

[0056] In the above embodiment, the coating device 1 is exemplified as being capable of moving the nozzle 2 relative to the coating target W, but the present invention is not limited to this configuration. For example, the coating device 1 may be configured to move a base or support member to which the coating target W is fixed relative to the nozzle 2. [Explanation of symbols]

[0057] 1 Coating device 2 nozzles 3 Assist air injection section 4 Cut air injection section AA Assist Air CA Cut Air M Coating material L1 Axis of the coating material discharged from the nozzle X Nozzle movement direction

Claims

[Claim 1] A coating device having a nozzle that moves in a predetermined direction while discharging a coating material downward, an assist air injection unit that injects assist air in a direction inclined with respect to the axis of the coating material discharged from the nozzle; and a cut air injection unit that cuts the coating material by injecting cut air at a predetermined angle with respect to the axis of the coating material discharged from the nozzle, the assist air jetting unit jets the assist air from behind the nozzle toward the coating material in a moving direction of the nozzle, The coating device is characterized in that the cut air spraying unit sprays the cut air toward the coating material from behind the nozzle relative to the movement direction of the nozzle.

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