Patent Grant
10919070
The present application is National Phase of International Application No. PCT/JP2017/004044 filed Feb. 3, 2017, and claims priority from Japanese Application No. 2016-047011, filed Mar. 10, 2016, the disclosure of which is hereby incorporated by reference herein in its entirety.
The present invention relates to a coating device.
A coating method of applying a coating agent such as a sealing material to a member surface by hand using a roller is performed as follows. First, a coating agent is spread on a pallet, the coating agent on the pallet is evenly applied to a roller, and thereafter, the coating is performed to the member surface. If the coating agent attached to the roller becomes thin as a result of application to the member surface, a coating agent is attached to the roller on the pallet. The coating operation is performed by repeating the above-described operations.
In the case of automating the coating operation using a roller by using a device such as a robot which performs a relative feed between the roller and a coating target, a configuration may be considered in which a container storing the coating agent is disposed to be adjacent to the roller, and the coating agent is supplied to the roller. According to this configuration, a step of attaching the coating agent to the roller on the pallet can be omitted.
The following PTL 1 discloses a technology which includes a coating chamber opened toward a roller and in which a coating material is supplied to a strip (a member covered with the coating material) from the coating chamber. An overflow gap is provided on a strip entry side of the coating chamber, and a strip running side is closed by a metering mechanism.
[PTL 1] Japanese Unexamined Patent Application Publication No. 63-256161
In a case where a coating operation is automatized, a roller performs a relative feed on a coating target and the roller is synchronously rotated with respect to the relative feed, and thus, the coating agent on the roller is transferred to the coating target. If an amount of the coating agent not applied to the member surface increases according to a rotation of the roller, the coating agent is accumulated in or is attached to an area other than an application surface of the roller. As a result, the coating agent which is accumulated in or adhered to an area other than the application surface of the roller falls down, which may cause a problem that an area, equipment other than the surface of the coating target is contaminated. In order to avoid the above-described problem, it is necessary to clean the roller or exchange the roller itself even when the roller is used for a short period of time.
A coating target is not limited to a case where the coating target is a uniform and flat surface. That is, the coating target may be tilted in a pitch direction or a roll direction with respect to a traveling direction of the roller or may have a step or unevenness. In a case where the coating operation is automatized, it is necessary to previously set a route through which the roller passes considering the tilt, the step, the unevenness of the coating target so that the roller can travel smoothly.
Respective components such as aircraft parts are roughly similar to each other in shape. However, in a case where coating is applied to various kinds of parts slightly inclined, stepped or uneven, a route of the roller needs to be set for each part, and thus, time and effort are required for programming.
In addition, when a rotational friction of the roller is large, the roller slips on a member surface, the roller does not synchronously rotate with respect to the relative feed, and a portion where the coating is not performed may be generated. A part supporting a shaft of the roller causes stick slip so that the roller does not synchronously rotate with respect to the relative feed, and the coating agent is applied to the member surface in a strip fashion, and thus, there is a problem that a thickness is uneven.
The roller may apply the coating agent, several times, to the coating agent applied to the coating target with a constant thickness, that is, over-coating may be performed to increase a thickness of the coating agent so as to achieve a required thickness of the coating agent. In this case, a friction force at an interface between the coating agent and the roller is low, and thus, the roller does not rotate (or the roller does not synchronously rotate with respect to translation of the roller) due to the stick slip, and as a result, the coating agent is not transferred, and there is a problem that a predetermined thickness of the coating agent cannot be realized.
The present invention is made in consideration of the above-described circumstances, and an object thereof is to provide a coating device capable of stably applying a coating agent to a coating target while preventing a supply of an excess coating agent.
According to a first aspect of the present invention, there is provided a coating device including: a roller which is rotated in one direction; a supply system which includes an opening formed with respect to the roller and supplies a coating agent via the opening; a first doctor blade which is provided at the side of the opening on a rotation exit side of the roller; and a second doctor blade which is provided at the side of the opening on a rotation entry side of the roller, in which a gap formed between the second doctor blade and the roller is larger than a gap formed between the first doctor blade and the roller.
According to this configuration, a rotation direction of the roller is one direction, and the gap between the second doctor blade provided on the rotation entry side of the roller and the roller can be largely set while an excess coating agent is prevented from being supplied by the first doctor blade provided on the rotation exit side of the roller. Accordingly, it is possible to prevent the coating agent from being accumulated in the outside of the roller.
In the above-described coating device, the second doctor blade may be provided on a front side in a traveling direction of the roller and vertically of above the roller and the second doctor blade may be installed at a position higher than that of the first doctor blade.
According to this configuration, an outflow limitation of the coating agent which tries to flow out from the gap between the second doctor blade provided on the rotation entry side of the roller and the roller further increases, and thus, the coating agent does not easily leak from the gap.
In the above-described coating device, the coating device may further include two shields which are provided on both end portions in an axial direction of the roller, and an opening width on the rotation entry side of the roller formed between the two shields may be wider than an opening width on the rotation exit side of the roller formed between the two shields.
According to this configuration, the coating agent is not easily accumulated in both end portions in the axial direction of the roller on the rotation entry side of the roller in the supply system.
According to a second aspect of the present invention, there is provided a coating device including: a roller which is rotated in one direction; and a support which is provided in the roller and is configured to tilt the roller in at least one of a pitch direction and a roll direction with respect to a relative traveling direction between the roller and a coating target.
According the above-described configuration, the roller is tilted in at least one of the pitch direction and the roll direction with respect to the relative traveling direction between the roller and the coating target, and thus, even in case where the coating target has an inclined surface or a threaded surface, it is possible to smoothly perform the application of the coating agent.
According to a third aspect of the present invention, there is provided a coating device including: a roller which is rotated in one direction; a supply system which includes an opening formed with respect to the roller and supplies a coating agent via the opening; and bearing members which are provided on both end sides of the roller and rotatably support the roller.
According to the above-described configuration, unlike a case where the rotation support of the roller is performed by a through rod installed to pass through the axis of the roller, when the coating agent is applied, the rotation of the roller is not easily stopped, and the roller does not easily generate the stick slip.
According to a fourth aspect of the present invention, there is provided a coating device including: a roller which is rotated in one direction; a supply system which includes an opening formed with respect to the roller and supplies a coating agent via the opening; a first friction member which is provided in a traveling direction of the roller on a work table side to which the coating agent is supplied; and a second friction member which is provided in a circumferential direction of the roller and comes in to contact with the first friction member.
According to the above described configuration, during the application of the coating agent, when the roller advances in the traveling direction, the second friction member installed on the roller and the first friction member installed on the work table come into contact with each other, and thus, the roller is reliably rotated.
According to a fifth aspect of the present invention, there is provided a coating device including: a roller which is rotated in one direction; a supply system which includes an opening formed with respect to the roller and supplies a coating agent via the opening; a rotation drive portion which rotationally drives the roller; and a controller which synchronizes a speed of the roller in a traveling direction and a rotation speed of the roller.
According to the above-described configuration, it is possible to rotate the roller at a predetermined speed synchronously with the speed in the traveling direction of the roller, and the coating agent can be uniformly applied to the surface of the coating target.
According to a sixth aspect of the present invention, there is provided a coating device including: a roller which is rotated in one direction; a supply system which includes an opening formed with respect to the roller and supplies a coating agent via the opening; and an adjustment unit which applies a friction force against a rotation of the roller and adjusts the friction force to be applied.
According to the above-described configuration, a rotational friction force generated in the roller can be adjusted by using the adjustment unit. For example, the rotational friction force generated in the roller increases to be higher than the friction force generated between the application target surface and the roller, and thus, the roller is not easily rotated. As a result, a thickness of the coating agent applied by once application can be thinner than a predetermined thickness.
According to the present invention, it is possible to stably apply the coating agent to the coating target while preventing a supply of an excess coating agent.
Hereinafter, a coating device according to a first embodiment of the present invention will be described.
For example, as shown in
For example, the coating device 1 according to the present embodiment is suitable for applying a material having a high viscosity. For example, in the sealing material applied to the aircraft part, the viscosity is from 50 Pa·s to 2500 Pa·s. The sealing material having this viscosity corresponds to a material having an intermediate viscosity or a high viscosity of 10 Pa·s or more within which a discharge control or spreading of the sealing material is difficult.
For example, as shown in
Means for automating the coating operation by the coating device 1 having the roller 2 is not limited to the robot, and it is possible to use a device other than the robot capable of performing a position control or a coating control of the coating device 1. As shown in
In the coating device 1, the surface of the coating target 11 is moved in one direction, and thus, the roller 2 is rotated in the one direction. In the present embodiment, in a state where the movement direction of the coating device 1 is not limited to two reciprocating directions and is limited to one direction, the coating operation is performed by the coating device 1. In the present embodiment, by limiting the movement direction of the coating device 1 to one direction, the rotation direction of the roller 2 is regulated in only one direction. In order to limit the rotation direction of the roller 2 to only one direction such that the roller 2 can be rotated in one direction, not only the moving direction of the coating device 1 is limited, but also means for regulating the rotation direction by a mechanical configuration such that the roller 2 is not rotated in the opposite direction may be provided in the coating device 1. For example, the regulating means is a one-way clutch, a ratchet mechanism.
For example, the tank 3 is an example of a supply system, is provided in the vicinity of a vertically uppermost member of the roller 2, and supplies the coating agent 10 stored inside the tank 3 to the roller 2. In the tank 3, an opening 8 is formed, and the coating agent 10 is supplied to the roller 2 via the opening 8. In the tank 3, a wall member 4 is provided on a rotation exit side of the roller 2 and a wall member 5 is provided on a rotation entry side of the roller 2 so as to be parallel in an axial direction of the roller 2.
A gap is formed between the wall member 4 on the rotation exit side of the roller 2 and the roller 2, and when the roller 2 is rotated, the coating agent 10 is supplied from the gap. Meanwhile, a gap is formed between the wall member 5 on the rotation entry side of the roller 2 and the roller 2, and when the roller 2 is rotated, an excess coating agent 10 which is not applied to the coating target 11 is returned from the gap.
Plate-shaped doctor blades 6 and 7 are respectively installed on the wall members 4 and 5 in the axial direction of the roller 2, and gaps between the doctor blades 6 and 7 and the roller 2 can be adjusted. The gap formed between the doctor blade 6 on the rotation exit side and the roller is adjusted according to a target coating thickness. According to the adjustment, by using the doctor blade 6, it is possible to prevent the excess coating agent 10 from being supplied.
The gap formed between the doctor blade 7 on the rotation entry side and the roller 2 is larger than the gap formed between the doctor blade 6 on the rotation exit side and the roller 2. In the present embodiment, the rotation direction of the roller 2 is limited to one direction, and thus, the rotation exit side and the rotation entry side are determined, and the respective functions can be divided. The rotation exit side and the rotation entry side are determined, and thus, the gap between the doctor blade 7 on the rotation entry side and the roller 2 can be set to be larger than the gap between the doctor blade 6 on the rotation exit side and the roller 2. As a result, the excess coating agent 10 which is not transferred to the coating target 11 can be returned to the tank 3, and it is possible to prevent the coating agent 10 from being accumulated in an outer side of the roller 2. In
According to the present embodiment, it is possible to prevent the coating agent from being accumulated in an outer side, which does not relate to the coating of the roller 2, such as outer sides of the doctor blades 6 and 7.
In the above-described present embodiment, the case is shown and described in which an intermediate portion of the tank 3 in a traveling direction of the roller 2 coincides with the uppermost portion of the roller 2 and installation heights of the doctor blades 6 and 7 are approximately the same as each other. However, the present invention is not limited to this.
For example, as shown in
As shown in
The shielding material 9 has an arc shape in the circumferential direction of the roller 2, and prevents the coating agent 10 stored inside the tank 3 from leaking to the outside. As shown in
In the present embodiment, the rotation direction of the roller 2 is limited to one direction, and thus, according to the above-described configuration, the excess coating agent 10 is reliably and easily returned into the tank 3 by the shielding materials 9 on the rotation entry side of the roller 2 in the tank 3. As a result, the coating agent 10 is not easily accumulated in the vicinity of both end portions in the axial direction of the roller 2 on the rotation entry side of the roller 2.
In the above-described embodiment, the case is described in which the shielding materials 9 which are in contact with the roller 2 are provided on the both end portions in the axial direction of the roller 2. However, the present invention is not limited to this. That is, as shown in
Similarly to the shielding materials 9, each of the shield 12 is obliquely provided in the axial direction of the roller 2, and an opening width on the rotation entry side of the roller 2 formed between the two shields 12 is wider than an opening width on the rotation exit side of the roller 2 formed between the two shields 12. According to this configuration, the excess coating agent 10 is reliably and easily returned into the tank 3 by the shield 12 on the rotation entry side of the roller 2 in the tank 3. As a result, the coating agent 10 is not easily accumulated in the vicinity of both end portions in the axial direction of the roller 2 on the rotation entry side of the roller 2.
In the above-described first embodiment, the shielding materials 9 or the shields 12, which are not provided to be perpendicular to the axial direction of the roller 2 but are obliquely provided in the axial direction, may not necessarily be provided, and the two shielding materials 9 or the two shields 12 may be installed to be parallel to each other.
Next, a coating device according to a second embodiment of the present invention will be described.
As shown in
The coating device 21 includes the roller 2 which is rotatable around a shaft and a tank (not shown) in which the coating agent 10 is stored.
The coating device 21 includes a support 22 which supports the roller 2, a base 23, a spring 24, and a spherical bearing 25
For example, the support 22 is a plate-shaped member which is long in the traveling direction of the roller 2, the roller 2 is supported by a lower surface side of the support 22, and an upper surface side of the support 22 is connected to the base 23 via the spring 24 and the spherical bearing 25. Two end plates 26 are installed on the lower surface side of the support 22, and the end plates 26 are connected to end portions of the shaft of the roller 2. Accordingly, the roller 2 is rotatably supported by the end plates 26.
The spring 24 includes a compression spring and is provided above the roller 2 in a state where the support 22 is interposed therebetween. A lower end of the spring 24 is connected to the support 22 and an upper end of the spring 24 is connected to the base 23. Two springs 24 are installed on a straight line parallel to the shaft of the roller 2. A rod 29 passes through a center of each spring 24 such that the compression spring reliably expands and contracts in a vertical direction.
The spherical bearing 25 passes through the center in the axial direction of the roller 2, and is installed on a straight line parallel in the traveling direction of the roller 2. An outer ring of the spherical bearing 25 is installed on an upper surface of the support 22 and a rod 51 which is connected to an inner ring of the spherical bearing 25 is connected to the base 23. The spherical bearing 25 is installed behind the roller 2 in the traveling direction of the roller 2. The roller 2 and the spherical bearing 25 are separated from each other, and thus, a vertically oscillating width of the roller 2 can increase.
According to the above-described configuration, the roller 2 can move in the vertical direction with respect to the base 23, and the axial direction of the roller 2 can be tilted with respect to the base 23. When the coating device 21 is pressed to the coating target 11, the roller 2 is always pressed to the surface of the coating target 11 by the springs 24.
In this way, while the coating operation is performed, the roller 2 can be tilted in the pitch direction and the roll direction with respect to the traveling direction of the roller 2 while the roller 2 is pressed to the surface of the coating target 11, and thus, even in the case where the coating target 11 has an inclined surface or a threaded surface, it is possible to smoothly perform the application of the coating agent 10. As a result, in a case where the coating operation is automatized, it is not necessary to set a route through which the roller passes, taking into account an inclination of the coating target. That is, in a case of aircraft parts, that is, even in a case where coating is applied to various kinds of parts having slightly different inclinations, it is not necessary to finely set a route for automatization for each part, and thus, the automatization of the coating operation is easily performed.
In the above-described embodiment, in the coating device 21, the case in which the spherical bearing 25 is used is described. However, the present invention is not limited to this example.
For example, as shown in
In the present modification example, similarly to the above-described embodiment, the springs 24 include compression springs and are installed above the roller 2 in a state where the support 22 is interposed therebetween. A lower end of each spring 24 is connected to the support 22 and an upper end of each spring 24 is connected to the base 23. Two springs 24 are installed on a straight line parallel to the shaft of the roller 2. A rod 29 passes through a center of each spring 24 such that the compression spring reliably expands and contracts in a vertical direction.
According to the above-described configuration, the roller 2 can move in the vertical direction with respect to the base 23, and the axial direction of the roller 2 can be tilted with respect to the base 23. When the coating device 21 is pressed to the coating target 11, the roller 2 is always pressed to the surface of the coating target 11 by the springs 24.
Next, a coating device according to a third embodiment of the present invention will be described.
As shown in
The coating device 31 includes the roller 2 which is rotatable around the shaft and a tank (not shown) in which the coating agent 10 is stored.
As shown in
Each of the bearings 34 includes an outer ring 35 and an inner ring 36, the outer ring 35 is connected to the end portion of the roller 2, and the inner ring 36 is connected to a connection member 37 provided on the end plate 33. One side of the connection member 37 is connected to the end plate 33, and the other side thereof is inserted into an inner periphery of the inner ring 36 of the bearing 34 so as to be connected thereto.
The bearings 34 are used, and thus, unlike a case where the rotation support of the roller 2 is performed by a through rod installed to pass through the axis of the roller 2, when the coating agent 10 is applied, the rotation of the roller 2 is not easily stopped, and the roller 2 does not easily generate the stick slip. As a result, the roller 2 can be synchronously rotated with respect to the relative feed, and the coating agent 10 can be uniformly applied to the surface of the coating target 11.
As shown in
Accordingly, during the application of the coating agent 10, when the roller 2 advances in the traveling direction, the meshing teeth 38 installed on the roller 2 mesh with the meshing teeth 39 installed on the work table 40, and thus, the roller 2 is reliably rotated. That is, by forcibly synchronizing the movement of the roller 2 in one direction and the rotation of the roller 2, the roller 2 can be synchronously rotated with respect to the relative feed, and the coating agent 10 can be uniformly applied to the surface of the coating target 11.
A member which is provided in the circumferential direction of the roller 2 and the work table 40 and forcibly synchronize the movement of the roller 2 in the one direction and the rotation of the roller 2 is not limited to the meshing teeth 38 and 39. For example, instead of the meshing teeth 38 and 39, a high friction member (for example, a sandpaper) having high friction surface properties may be provided in the circumferential direction of the roller 2 and the work table 40.
As shown in
In addition, in the above-described embodiment, when the application of the roller 2 is performed, the case where the roller 2 is passively rotated by the friction force between the roller 2 and the coating agent 10 and the case where the roller 2 is passively rotated by the meshing teeth 38 attached to the roller 2 and the meshing teeth 39 or the high friction member are described. However, as shown in
Accordingly, it is possible to rotate the roller 2 at a predetermined speed synchronously with the speed in the traveling direction of the roller 2, and the coating agent 10 can be uniformly applied to the surface of the coating target 11.
The present embodiment is not limited to the case where the roller 2 is moved in one direction by the arm 61 of the robot 60 and can be applied to a case where the position of the roller 2 is fixed and the working table on which the coating target 11 is placed is moved. That is, a controller of the work table and the servo motor 53 transmit and receive signals, and the servo motor 53 rotates the roller 2 at the rotation speed of the roller 2 based on a relative speed between the roller 2 and the work table.
In the above description, in the coating device 31, with respect to the roller 2, the configuration in which the bearing 34 is provided, the configuration in which the meshing teeth 38 and 39 are provided, and the configuration in which the servo motor 53 is provided are described separately. However, all configurations may be combined with each other, or one or two of the configurations may be selected.
Next, a coating device according to a fourth embodiment of the present invention will be described.
As shown in
The coating device 41 includes the roller 2 which is rotatable around the shaft and a tank (not shown) in which the coating agent 10 is stored.
The coating device 41 includes a support 42 which supports the roller 2, a friction plate 43 which is provided on an end surface of the roller 2, adjustment units 44 which come into contact with the friction plate 43
Two end plates 45 are installed on a lower surface side of the support 42. Each of the end plates 45 is connected to the end portion of the shaft of the roller 2 via a bearing 46. Accordingly, the roller 2 is rotatably supported by the bearings 46.
The friction plate 43 is an annular plate-shaped member and is provided on one end surface positioned on an axial end portion of the roller 2.
Each of the adjustment units 44 includes a screw portion 47, a contact member 48, a compression spring 49. The screw portion 47 is installed to be screwed to a screw hole 54 formed in the end plate 45 and a position of the screw portion 47 is changed in the axial direction. The contact member 48 is a plate-shaped member which comes into contact with the friction plate 43 on one surface side, and the other surface side of the contact member 48 is connected to the compression spring 49. A through rod 50 which passes through the center of the compression spring 49 may be provided in the contact member 48. The compression spring 49 can be reliably expanded and contracted in the axial direction by the through rod 50. On end portion of the compression spring 49 is connected to an end portion of the screw portion 47, and the other end portion thereof is connected to the contact member 48.
Each of the contact members 48 is always pressed to the friction plate 43 of the roller 2 by an elastic force of the compression spring 49. The axial position of the adjustment unit 44 can be adjusted, and thus, a distance between the adjustment unit 44 and the contact member 48 is changed. Accordingly, the elastic force generated by the compression spring 49 is changed, and a force for pressing the contact member 48 to the friction plate 43 is changed. As a result, a rotational friction force generated in the roller 2 is adjusted.
For example, the rotational friction force generated in the roller 2, that is, the friction force of the rotary shaft of the roller 2 is determined based on a graph shown in
The roller 2 applies the coating agent 10, several times, to the coating agent 10 applied to the coating target 11, that is, over-coating is performed, and thus, the thickness of the coating agent 10 increases. In a case where a sealing material is applied to the aircraft part, the over-coating is performed before the last applied sealing material is completely dried. In this case, as the thickness of the coating agent 10 increases (that is, as the number of over-coating increases), the friction force generated between the application target surface and the roller 2 gradually decreases. If the rotational friction force generated in the roller 2 is larger than the friction force generated between the application target surface and the roller 2, the roller 2 slides on the coating agent 10, the roller 2 is not easily rotated, and as a result, the thickness of the coating agent 10 applied by once application decreases.
A relationship between the axial position of the adjustment unit 44 and the rotational friction force generated in the roller 2 or a relationship between the friction force generated between the application target surface and the roller 2 and the thickness of the coating agent 10 are acquired by experiment in advance.
In the present embodiment, each of the adjustment units 44 adjusts the rotational friction force generated in the roller 2 using the above-described relationships. For example, in a case where the thickness of the coating agent 10 applied by once application is less than a predetermined thickness, the rotational friction force generated in the roller 2 increase to be higher than the friction force generated between the application target surface and the roller 2, and thus, the roller 2 is not easily rotated. As shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 2016-047011 | Mar 2016 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2017/004044 | 2/3/2017 | WO | 00 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2017/154433 | 9/14/2017 | WO | A |
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