JP2005230642A - Coating nozzle for protective film material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating nozzle for a protective film material with which an excellent coating film having uniform and desired film thickness distribution is formed in the application of a coating liquid for the protective film. <P>SOLUTION: This coating nozzle for the protective film material is provided with a tip part 1 formed from a part of a spherical surface, a cylindrical drum part 3 extending to the tip part 1 and incorporating a hollow axial core 2, a coating liquid supply passage 2 formed by closing the hollow axial core 2 with the inside of the tip part 1 and having a blind tube structure, and a discharge part composed of a linear slit 4 having a depth reaching the coating liquid supply passage 2 from the tip part 1. A closed end part 5 of the coating liquid supply passage 2 is formed from a semi-spherical surface 5a, and passage wall surfaces 4c and 4d are formed from the most deep linear grooves 4a and 4b of the linear slit 4 and both spherical surfaces of the tip end part spherical surface 1a and the semi-spherical surface 5a respectively extending to the linear grooves 4a and 4b. The distance L between both the spherical surfaces 1a and 5a of the wall surfaces 4c and 4d is in a range equal to or larger than the radius (r) of the close end part semi-sphere 5a and equal to or smaller than the diameter (2r) of the semi-sphere 5a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a coating nozzle for a protective film material. This protective film is intended to cover, for example, an automobile body.

  When the finished vehicle is shipped to the factory, measures such as damage to the vehicle during transportation to the dealership, acid rain and feces, or cargo environment during the long maritime transport period at the time of import / export, such as the roof A flat surface such as a hood or trunk is covered with a protective film called a liquid wrap. This coating film is made of a relatively low-viscosity coating material. During assembly and disassembly at the factory, the coating solution that has been allowed to flow naturally from the nozzle is stretched and dried to form a film. It is formed. However, since the stretching of the coating liquid is performed manually using a roller, the work requires manpower.

  In order to automate this coating film forming operation, it is conceivable to spray a material coating liquid on the vehicle body to be coated, for example, with a spray gun for coating. However, in this case, there is a possibility that the coating liquid misted by the spray gun is scattered and adheres outside the surface range to be coated. For this reason, it becomes difficult to form a single film having a uniform film thickness on the entire flat surface of the vehicle body. Furthermore, the coating film surface formed using the misted coating liquid has a large degree of scattering of the coating liquid especially at the edge portion, and it is difficult to form a boundary line that can be clearly distinguished from the non-coating surface. .

  In order to easily peel the coated film, it is desirable to give the film edge part a certain thickness, but it is not easy to thicken the edge part formed in this way. . Therefore, when a coating film is formed using a spray gun, there is a problem that film peeling cannot be reliably and easily performed when the protective film is detached.

An application nozzle for applying a high-viscosity liquid such as a sealing material is disclosed in, for example, Patent Document 1. When a coating film of a protective film material is applied using this, a material coating liquid assumed by the application nozzle is used. Due to the lower viscosity of the protective film material, various problems are expected to occur.
Japanese Utility Model Publication No. 7-7771 (FIGS. 4 to 6)

  That is, the first aspect of what is disclosed in Patent Document 1 is that the outer shape of the tip of the coating nozzle has a spherical shape, and the inner wall surface corresponding to the end of the blind pipe structure of the supply flow path is formed on the inner side of the tip. By adopting the shape, the thickness of the slits constituting the liquid ejection part is made substantially constant, and the uniformity of the coating pattern is ensured. However, since the connecting portion between the cylindrical base portion and the conical end portion of the blind pipe structure of the supply channel and the inner surface portion at the connecting portion between the truncated cone slope and the top surface of the truncated cone are bent, When a low-viscosity protective film material coating liquid is used, the flow of the coating liquid is not uniform at these bent portions, thereby causing an imbalance in the discharge pressure. As a result, uniform discharge of the coating liquid is hindered, and it is difficult not only to form a coating film with a uniform or desired film thickness on the coated surface, but also bubbles are generated in the coating liquid immediately before discharge. There is a risk of degrading the quality of the coating film.

  In addition, the second aspect of the present invention further improves the stabilization of the wall thickness, which was incomplete in the first aspect, by making both the tip outer shape of the coating nozzle and the inner wall surface inside the tip part spherical. To do. However, even in this case, when a protective film material coating liquid is used, a bent portion remains at the inner surface portion of the connection portion between the cylindrical base portion of the blind pipe structure and the spherical terminal portion of the supply flow path. Uniformity is not ensured, and there is still a risk of bubble formation. Further, since the bent portion remains in the third aspect of this, the concern about the occurrence of these problems remains unresolved as in the first and second aspects.

  In view of the above-mentioned problems, the present invention provides a coating nozzle for a protective film material that enables the formation of a good coating film having a uniform and desired film thickness distribution, particularly when coating a protective film material coating liquid. Is an issue. Note that the desired film thickness distribution in this case includes, for example, locally generating a constant film thickness change.

  In order to solve the above problems, a coating nozzle for a protective film material according to the present invention includes a distal end portion formed of a part of a spherical surface, a hollow cylindrical body portion connected to the distal end portion, and a hollow shaft core of the cylindrical body portion. A blind tube of the coating liquid supply flow path comprising a coating liquid supply flow path having a blind tube structure that is closed inside the portion and a discharge section that is formed by a straight slit having a depth reaching the coating liquid supply flow path from the tip. The closed wall of the structure is formed of a hemispherical spherical surface, and the flow path wall surface is formed by the deepest straight groove of the linear slit and the spherical surface of the tip and the hemispherical spherical surface of the closed end respectively. The distance between both spherical surfaces of the wall surface is within the range of not less than the radius and not more than the diameter of the closed end hemisphere.

  According to this, the contact distance of the coating liquid that passes through the slit serving as the discharge port is ensured to be relatively large with respect to the wall surface of the flow path that faces through the slit. And since the directionality of coating liquid discharge is stabilized by this, even if it uses comparatively low-viscosity protective film material coating liquid, the favorable coating film formation which has uniform or desired film thickness distribution can be performed reliably. .

  This is because the discharge pressure and flow rate of the coating liquid supplied from the coating liquid supply flow path are considered to correlate with the radius of the hemisphere that forms the closed tube structure closed end portion of the coating liquid supply flow path. In particular, in the case of a coating liquid having a relatively low viscosity such as the above-described protective film material, the flow velocity is relatively large compared to a high-viscosity material such as a sealing material, and the directionality at the time of external discharge is important when forming a painted surface. Influence. That is, when the discharge coating liquid passes through the opposing flow path wall surface through the slit constituting the discharge port, the spherical surface of the tip and the closed end are secured so that the contact distance between the coating liquid and the flow path wall surface is secured. By keeping the distance between both spherical surfaces of the partial hemisphere within the range of the radius of the closed end hemisphere and below the diameter at any part of the flow path wall surface, the discharge direction of the coating liquid can be converged within the predetermined range. In addition, it is possible to apply a coating liquid with a reduced diffusion spread.

  In addition, a part of the peripheral surface of the cylindrical body includes a pair of symmetry points at symmetrical positions across the hollow shaft core on the deepest straight groove of the linear slit, and is parallel to the hollow shaft core. By forming a pair of parallel planar shapes that are orthogonal to the linear direction of the slit and reach the tip spherical surface, a good coating film having a desired film thickness distribution can be formed.

  This is because, in the vicinity of the deepest straight groove of the slit, the straight slit is cut off by a pair of parallel planes to form a linear outer end, and the distance between the two spherical surfaces on the channel wall surface is from other parts. This is because it becomes relatively small. At this time, at the pair of symmetrical points at symmetrical positions across the hollow shaft core on the deepest straight groove of the slit, the diffusion degree of the coating liquid discharge becomes approximately the same. Then, the discharge coating from these point positions reaches the coating film portion to be formed with a relatively uniform film thickness by the coating liquid discharged through the adjacent portion where the distance between both spherical surfaces is relatively large. The liquid diffuses to form a painted surface. At this time, at the end of the coating surface portion to be formed with a uniform film thickness, a coating film is formed in a state where the diffused discharge coating liquid is added, and the coating film formation is performed at the position of the symmetry point. Each is done correspondingly. Thus, it is possible to form a coating film having a desired film thickness distribution in which the bead end is raised on the painted surface.

  Note that the spherical shape of the tip and the hemispherical shape of the closed end of the blind tube structure do not necessarily have the same spherical center as long as they are on the same axis line that matches the hollow axis of the cylindrical body. For example, even when these spherical center positions are different from each other, the deepest straight groove of the slit is symmetrically arranged with the hollow shaft core interposed therebetween. For this reason, the contact distance between the coating liquid discharged through the vicinity of the deepest straight groove and the flow path wall faced through the slit is symmetrically about the same across the hollow shaft core. Also in this case, the linear outer end portion is formed in the linear slit by the pair of parallel planes described above, so that in the vicinity of the slit deepest straight groove, between the two spherical surfaces on the flow path wall surface from the other portions. The distance is relatively small. That is, by performing coating using the coating nozzle for the protective film material having such a shape, for example, it is possible to surely form a coating film having a desired film thickness distribution such that the end of the bead rises on the coating surface. .

  The protective film in the state of covering the vehicle body improves workability by starting the peeling from both ends of the raised bead, so that the entire film can be detached in a single peeling operation. Can be expected.

  The coating nozzle for protective film material according to the present invention is configured so that the distance between the spherical surface of the tip and the hemispherical surface of the coating liquid supply channel closed end is the radius of the closed end hemisphere at any part of the channel wall surface. Since the direction of discharge of the coating liquid is stabilized by being within the range of the above diameter and below the diameter, even when a protective film material coating liquid having a relatively low viscosity is used, a uniform coating film having a uniform or desired film thickness distribution is obtained. The certainty when forming is increased.

  In addition, it includes a pair of symmetrical points at symmetrical positions across the hollow shaft core on the deepest straight groove of the straight slit, and is parallel to the hollow shaft core and orthogonal to the straight slit, and the tip spherical surface Are formed as a part of the peripheral surface of the cylindrical body, so that the linear outer end is formed in the straight slit, and in the vicinity of the deepest straight groove of the slit, The distance between the two spherical surfaces on the flow path wall surface is relatively smaller than the portion other than the above. As a result, the diffusion degree of coating liquid discharge in the vicinity of the slit deepest straight groove becomes relatively large. Then, the discharged and discharged liquid from the vicinity diffuses to the coating film portion to be formed with a relatively uniform film thickness by the coating liquid discharged through the adjacent portion having a relatively large distance between both spherical surfaces. To form a painted surface. Since this is performed corresponding to the positions of the symmetry points, it is possible to form a coating film having a desired film thickness distribution in which both ends of the beads rise on the painted surface.

  FIG. 1 is a schematic view showing a first embodiment of the coating nozzle for protective film material of the present invention. FIG. 1 (a) shows a schematic top view, and FIG. 1 (b) shows an AA line of the schematic top view. A cross-sectional view is shown. This application nozzle is for performing airless coating of the supply coating liquid, and includes a tip portion 1 formed of a part of a spherical surface, a cylindrical body portion 3 incorporating a hollow shaft core 2 connected to the tip portion 1, A coating liquid supply channel 2 having a blind tube structure that closes the hollow shaft core 2 inside the tip portion 1, and a discharge unit 4 including a straight slit 4 having a depth reaching the coating solution supply channel 2 from the tip portion 1. In contrast to the basic configuration, the closed end portion 5 of the coating liquid supply flow channel 2 is formed of a hemispherical spherical surface 5a, and the deepest straight grooves 4a and 4b of the straight slit 4 and the tip portions respectively passing through the straight grooves 4a and 4b. In the flow path wall surfaces 4c and 4d formed by both the spherical surface 1a and the hemispherical spherical surface 5a, the distance L between the spherical surfaces 1a and 5a of these wall surfaces 4c and 4d is greater than or equal to the radial distance r of the closed end hemisphere 5a. In addition, a configuration in which the diameter distance is 2 r or less is added.

  The distance L in this case indicates the shortest length of each arbitrary point position of the tip spherical surface 1a and the hemispherical spherical surface 5a. That is, in FIG. 1B, the lengths between the zenith positions 1b and 5b of the tip spherical surface 1a and the hemispherical spherical surface 5a can be referred to as “distances”. The length between the zenith position 5b is outside the definition of “distance”.

  Further, the portion below the straight grooves 4 a and 4 b of the slit 4 is formed as a cylindrical body portion 3 of the coating nozzle, and surrounds the coating liquid supply channel 2 connected to the hemisphere 5 a constituting the closed end portion 5 of the blind tube structure 2. To do. Furthermore, the lower end portion of the body portion 3 is formed with a desorption portion 3a for desorption to a coating liquid supply pipe (not shown) connected to the main application nozzle.

  When airless coating is performed with a relatively low viscosity coating liquid made of a protective film material using the coating nozzle shown in FIG. 1, the flow path wall surfaces 4 c and 4 d facing each other through the slit 4 and the discharge formed by the slit 4 are used. Since the contact distance with the coating liquid passing through the outlet is relatively large, the direction of coating liquid discharge is stable, and it is possible to reliably form a good coating film to meet the desired film thickness distribution. become.

  This is because the discharge pressure and flow velocity of the coating liquid supplied from the coating liquid supply channel 2 are considered to correlate with the radius r of the hemisphere 5a of the closed end 5 in the blind tube structure of the coating solution supply channel 2. is there. In particular, in the case of a coating solution with a relatively low viscosity such as a protective film material, the flow rate is relatively large compared to a high-viscosity material such as a sealing material. Influence. When the discharge coating liquid passes through the flow path wall surfaces 4c and 4d facing each other through the slit 4 constituting the discharge port, the tip spherical surface 1a corresponding to the contact distance between the coating liquid and the flow path wall surfaces 4c and 4d, and By keeping the distance L between the two spherical surfaces of the hemispherical spherical surface 5a within the radius distance r and the diameter distance 2r of the closed end hemisphere 5a, the discharge direction of the coating liquid can be converged within a predetermined range, thereby diffusing. It becomes possible to apply a coating liquid with a reduced degree of. Therefore, by performing airless coating using the coating nozzle having the structure shown in FIG. 1, it is possible to form a good coating film having a uniform film thickness distribution.

  By the way, in the coating nozzle shown in FIG. 1, the spherical surface 1a and the hemisphere 5a are set to have the same spherical center, and the distance L is made constant at any part of the flow path wall surfaces 4c and 4d constituting the slit 4. However, for example, the distance L on the slit 4 can be locally made different by making the spherical center positions of the spherical surface 1a and the hemisphere 5a different from each other. As described above, the distance L corresponding to the contact distance between the coating liquid and the flow path wall surfaces 4c and 4d is an increase / decrease factor of the degree of diffusion in the coating liquid discharge direction. It is possible to form a coating film with a film thickness distribution of.

  FIG. 2 shows a schematic diagram of a coating nozzle for a protective film material that enables the formation of a coating film with such a desired film thickness distribution as a second embodiment of the present invention. That is, FIG. 2A shows a schematic top view, and FIG. 2B shows a cross-sectional view taken along the line BB of the schematic top view. A tip end portion 1 formed of a part of a spherical surface, a cylindrical body portion 3 containing a hollow shaft core 2 connected to the tip end portion 1, and a blind tube structure coating liquid supply that closes the hollow shaft core 2 inside the tip end portion 1 In contrast to the basic configuration including the flow path 2 and the discharge section 4 including the straight slit 4 having a depth reaching the coating liquid supply flow path 2 from the tip portion 1, the closed end portion 5 of the coating liquid supply flow path 2 is provided. Channel wall surface 4c formed by hemispherical spherical surface 5a and formed by deepest straight grooves 4a and 4b of linear slit 4 and both spherical surfaces of tip spherical surface 1a and hemispherical spherical surface 5a respectively passing through linear grooves 4a and 4b, 4d, the distance L between the spherical surfaces 1a and 5a of the wall surfaces 4c and 4d is added within the range of the radial distance r of the closed end hemisphere 5a and the diameter distance 2r or less. This is the same as the first mode shown.

  On the other hand, the difference from the structure of the coating nozzle shown in FIG. 1 is that a part of the peripheral surface of the cylindrical body 3 is sandwiched between the core shaft 7 of the hollow shaft core 2 on the deepest straight grooves 4a, 4b of the linear slit 4. And a pair of symmetry points 4e and 4f at symmetrical positions, which are parallel to the core axis 7 and perpendicular to the linear direction of the slit 4, and are symmetrical points 1e and 1f on the tip spherical surface 1a. It is a point formed by a pair of mutually parallel planes 6a and 6b.

  A coating film having a desired film thickness distribution can be formed by the protective film material application nozzle shown in FIG. This is because the distance L ′ on the flow path wall surfaces 4c and 4d is smaller in the vicinity of the deepest straight grooves 4a and 4b of the slit 4 than in other portions.

  That is, the diffusion degree of the coating liquid discharge in the vicinity of the deepest straight grooves 4a and 4b of the slit 4 is symmetrically about the same. Then, the discharged discharge liquid from the distance L ′ portion diffuses to the coating film portion to be formed with a relatively uniform film thickness with the discharged coating liquid from the distance L portion, thereby forming a painted surface. At this time, the coating film is formed in a state where the diffused discharged coating liquid is added at the end of the painted surface portion to be formed with a uniform film thickness. This coating film formation is performed corresponding to each of the above-mentioned symmetric positions, and thus a coating film having a desired film thickness distribution in which the bead end swells on the painted surface can be performed. In particular, the film protective film formed in a shape in which both ends of the bead swell on the painted surface is convenient for removing the entire film in one peeling operation.

  And by performing such application | coating, the coating-film formation which has the desired film thickness distribution that a bead edge part swells on a coating surface, for example can be performed reliably. The protective film in the state of covering the vehicle body improves workability by starting the peeling from both ends of the raised bead, so that the entire film can be detached in a single peeling operation. Can be expected.

  The coating nozzle for protective film material of the present invention can be used as a component part of an automated apparatus for reliably forming a desired protective film having a desired and uniform film thickness distribution.

(A) Schematic top view of the first embodiment application nozzle of the present invention (b) Cross-sectional view taken along line AA shown in FIG. (A) Schematic top view of second embodiment coating nozzle of the present invention (b) Cross-sectional view taken along line BB shown in FIG. 2 (a)

Explanation of symbols

1 Tip 1a Tip spherical surface 2 Coating liquid supply flow path (hollow shaft center, blind tube structure)
3 Cylindrical body 4 Straight slit 4a 4b Slit deepest straight groove 4c 4d Channel wall surface 4e 4f Symmetry point 5 Closed end 5a Hemisphere (semispherical spherical surface)
6a 6b Plane 7 Core axis L L ′ Distance r Hemispheric radius

Claims (2)

A distal end portion composed of a part of a spherical surface, a hollow cylindrical body portion connected to the distal end portion, and a coating liquid supply channel having a blind tube structure in which a hollow shaft core of the cylindrical body portion is closed inside the distal end portion; And a discharge section composed of a straight slit having a depth reaching the supply flow path from the tip portion, and forming a blind tube structure closed end portion of the supply flow path with a hemispherical spherical surface, and a deepest straight groove of the slit And a flow path wall formed by both the spherical surface of the tip and the hemispherical spherical surface of the closed end respectively passing through the linear groove, and the distance between the spherical surfaces of the wall is the closed end hemisphere A coating nozzle for a protective film material, wherein the coating nozzle is within the range of not less than the radius and not more than the diameter. A part of the peripheral surface of the cylindrical body part includes a pair of symmetry points at symmetrical positions across the hollow shaft core on the deepest straight groove of the slit, and is parallel to the hollow shaft core and the slit. The coating nozzle for a protective film material according to claim 1, wherein the coating nozzle is a pair of parallel planes that are orthogonal to the linear direction and reach the spherical surface of the tip portion.

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