COATING FILM, AUTOMOBILE, AND COATING METHOD

A coating film is provided on the surface of a car body of an automobile and includes a plurality of protruding portions extending from the front toward the rear along the car body.

TECHNICAL FIELD

Disclosed embodiments relate to a coating film, an automobile, and a coating method.

BACKGROUND ART

For example, there has been proposed a coating method in which unevenness is provided on the surface of an object to be coated such as an automobile to enhance heat radiation.

CITATION LIST

Patent Literature

Patent Document 1: JP 2016-93774 A

Patent Document 2: JP 2008-253974 A

SUMMARY OF INVENTION

A coating film according to one aspect of the embodiments is located on the surface of a car body of an automobile and includes a plurality of protruding portions extending from the front toward the rear along the car body.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of a coating film, an automobile, and a coating method disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited by the following embodiments.

Configuration of Coating Device

First, an overview of a coating device used for coating a car body will be described with reference toFIG.1.FIG.1is an explanatory diagram illustrating an example of a coating device. For the sake of clarity,FIG.1illustrates a three-dimensional orthogonal coordinate system including a Z-axis in which the vertically upward direction is a positive direction and the vertically downward direction is a negative direction. Such orthogonal coordinate systems may also be presented in other drawings used in the description below. The same components as those of a coating device1illustrated inFIG.1are denoted by the same reference numerals, and descriptions thereof will be omitted or simplified.

As illustrated inFIG.1, the coating device1includes a head10, a robot20, and a control device40.

The head10is fixed to the robot20. The head10moves according to the operation of the robot20controlled by the control device40.

The head10coats a car body30by depositing a coating material discharged from a plurality of discharge holes11located on a nozzle surface12onto a surface of the car body30to be coated, facing the nozzle surface12.

The head10is supplied with a coating material from a tank (not illustrated). The head10discharges the coating material supplied from the tank. The coating material is a mixture including a volatile component and a nonvolatile component, and has fluidity. The tank may be a reservoir (not illustrated) contained in the head10.

The volatile component is, for example, water, organic solvent, or alcohol and adjusts the physical properties of the coating materials, such as viscosity and surface tension. The nonvolatile component includes, for example, a pigment, a resin material, and an additive. The pigment includes one or a plurality of colored pigments used depending on the desired coating color. The resin material adheres to the car body30to be coated to form a film. The additive is a functional material that is added, for example for purposes of weather resistance.

Note that the coating material supplied to the discharge holes11is prepared such that a desired coating color is expressed by mixing a plurality of colored pigments or coating materials at predetermined proportions.

The robot20holds the head10. The robot20is, for example, a six-axis articulated robot. The robot20may be, for example, a vertical articulated robot or a horizontal articulated robot. The robot20includes a plurality of arms21each of which has the head10fixed to a tip of the arm21. The robot20is fixed to, for example, a floor, a wall, or a ceiling. Note that as long as the held head10can be moved properly, there is no limit to the degree of freedom of the arms21included in the robot20.

The control device40controls the coating device1. The control device40includes a controller41that controls the coating device1, and a storage unit45. The controller41includes a discharge controller42and an operation controller43.

The controller41includes a computer or various circuits including, for example, a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), and an input/output port. The CPU of such a computer functions as the controller41by, for example, reading and executing a program stored in the ROM. The controller41may also include hardware such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA). The discharge controller42controls the head10based on the configuration information stored in the storage unit45, and discharges the coating material from the plurality of discharge holes11toward the car body30. The operation controller43controls operations of the plurality of arms21based on the configuration information stored in the storage unit45, and controls movement of the head10via the arms21. The distance between the head10and the car body30is maintained at, for example, approximately from 0.5 to 14 mm.

The storage unit45corresponds to, for example, the ROM and the HDD. The ROM and the HDD can store the configuration information for various controls in the control device40. The storage unit45stores information related to discharge control of the coating material by the head10. Further, the storage unit45stores information related to the operation control of the plurality of arms21. The storage unit45may store data input by the user's instruction operation using a terminal apparatus (not illustrated) as instruction data for operating the robot20. Further, the controller41may also obtain the configuration information via another computer or portable storage medium connected by a wired or wireless network.

The car body30is a car body of an automobile. The car body30is placed on a conveying device (not illustrated), and is carried in and out. The coating device1according to an embodiment coats the car body30in a state where the conveying device is stopped. The coating device1may coat the car body30while the car body30is being repeatedly conveyed and stopped, or may coat the car body30simultaneously while the car body30is being conveyed.

FIG.2is a cross-sectional view illustrating an example of an automobile according to an embodiment. An automobile60illustrated inFIG.2includes a base member31, a primer layer32, a first coating layer33, and a second coating layer34. Here, the automobile60includes one or a plurality of power sources, such as an engine or a motor, and refers to a vehicle running on a road with three or more wheels without using rails or overhead lines. The automobile60may be, for example, a private vehicle or a commercial vehicle, and there is no limitation on the use of the automobile60.

The base member31is, for example, a steel plate processed into a predetermined shape, and is subjected to an electrodeposition process as necessary to impart rust resistance. The primer layer32is provided for imparting weather resistance, color development, and peeling resistance, for example. The first coating layer33is, for example, a base layer that has smoothness and weather resistance and imparts a desired coating color. A surface of the first coating layer33serves as a to-be-coated surface30ato be coated by the coating device1according to the embodiment.

A second coating layer34is located on the first coating layer33serving as the to-be-coated surface30a. The second coating layer34is located in a manner to cover a portion of the first coating layer33, for example, with a coating material having a coating color different from that of the first coating layer33. As a result, the car body30becomes a coated automobile60that is coated in a so-called two tone color in which a region36where the second coating layer34is located and a region35where the first coating layer33is exposed without the second coating layer34being located are aligned with an end portion37of the second coating layer34as a boundary.

In the example illustrated inFIG.2, the coating device1arranges the second coating layer34on the to-be-coated surface30aon the first coating layer33, but the embodiments are not limited to the example, and the coating device1may be used, for example, to arrange the first coating layer33on a coated surface32aof the primer layer32.

Note that the automobile60is not limited to the example illustrated inFIG.2. For example, a coating layer (not illustrated) may be located on the surface of the region35or36. Further, the second coating layer34may not be provided, and only the first coating layer33may be provided, or the second coating layer34may be located on the entire surface of the first coating layer33. Further, the car body30or the automobile60may further include one or a plurality of layers (not illustrated). In the following description, the first coating layer33and the second coating layer34are collectively referred to as a coating film50without distinction, and the base member31and the primer layer32are collectively referred to as the car body30without distinction.

First Embodiment

FIG.3is a plan view illustrating an example of an automobile according to a first embodiment.FIG.4is a cross-sectional view taken along line A-A inFIG.3.FIG.5is a side view illustrating an example of an automobile according to the first embodiment.

The automobile60according to the first embodiment includes a plurality of protruding portions55extending along the car body30from the front toward the rear (from a front end61toward a rear end62). The plurality of protruding portions55are formed, for example, along the Y axis direction on the surfaces of the coating films50coated on a bonnet64, a roof65, and side face doors66and67located on a side face63of the car body30. Each protruding portions55have a shape extending from the front toward the rear along the car body30. For example, on the bonnet64or the roof65, a plurality of protruding portions55are arranged in the width direction along the car body30, and on the side faces of the car body30, a plurality of protruding portions55are arranged in the height direction along the car body30. That is, the plurality of protruding portions55are arranged along the car body30in the width direction or the height direction.

The plurality of protruding portions55protrude in the thickness direction of the coating film50on the surface of the coating film50, and may be formed, for example, by a difference in the thickness of the coating film50. That is, the thickness of the coating film50can be made thicker in the protruding portion55than in the portion where the protruding portion55is not arranged. When the protruding portion55is formed by the difference in the thickness of the coating film50, the protruding portion55can be easily formed at the time of coating by using, for example, an inkjet head to change the discharge amount of the coating material depending on the location. That is, a coating method can be used in which a coating material is discharged toward the to-be-coated surface of the car body30, and a plurality of protruding portions55extending from the front toward the rear along the car body30are formed on the surface of the coating film50. In place of the difference in thickness of the coating film50, the difference in thickness of the base member31or the primer layer32may form the protruding portion55on the surface of the coating film50, and the curvature of the base member31may form the protruding portion55on the surface of the coating film50.

InFIG.4, the height h of the protruding portion55may be, for example, 20 μm to 150 μm. An interval d between the adjacent protruding portions55may be, for example, 20 μm to 150 μm. Similarly, the width of the protruding portion55may be, for example, 20 μm to 150 μm.

Thus, the coating film50on the surface of the car body30includes a plurality of protruding portions55extending along the car body30from the front toward the rear. That is, the automobile60includes the plurality of protruding portions55extending from the front toward the rear along the car body30on the surface of the coating film50. This allows the automobile60to have the effect of reducing frictional resistance during travel, for example, by reducing air flow rate between adjacent protruding portions55.

The automobile60may also obtain the effect of reducing pressure resistance, by a plurality of protruding portions55, for example, due to reduction of boundary layer separation by causing turbulence. The shape, the size, the arrangement, or the like of the protruding portion55of the car body30can be appropriately set in accordance with the desired effect and the degree of the frictional resistance reduction effect and the pressure resistance reduction effect. For example, in the direction from the front toward the rear of the car body30(the direction from the front end61toward the rear end62along the Y axis), when the plurality of protruding portions55are provided in a portion (for example, the portion indicated by P1inFIG.3) located in front (front end61side) of a portion (inFIG.3, for example, near the front end of the rear glass68) where the ratio of the decrease in the cross-sectional area (the cross-sectional area of the cross-section perpendicular to the direction from the front toward the rear of the car body30) of the car body30increases, the effect of reducing the pressure resistance of the automobile60by reducing the boundary layer separation can be enhanced.

The dimensions such as the height h, the width, and the interval d of the protruding portion55described above are not limited to the numerical range described above, and may be made smaller or larger. For example, when it is desired to increase the effect of generating turbulence, it is effective to increase the height h of the protruding portion55. The dimensions such as the height h, the width, and the interval d of the protruding portion55may be substantially different from each other.

Second Embodiment

FIG.6is a plan view illustrating an example of an automobile according to a second embodiment.FIG.7is a side view illustrating an example of an automobile according to the second embodiment.

An automobile60according to the second embodiment includes a plurality of protruding portions55extending along a direction inclined with respect to a direction (the direction from a front end61toward a rear end62along the Y axis) from the front toward the rear of a car body30on the surface of a coating film50coated on a roof65and a rear side face door67. The roof65has the plurality of protruding portions55extending from the front end61of the car body30toward a side face63, and the side face door67has the plurality of protruding portions55extending obliquely upward along the side face63of the car from the front toward the rear of the car body30. In this manner, the plurality of protruding portions55may have a configuration to include portions extending along a direction inclined with respect to a direction from the front toward the rear of the car body30. When the automobile60has such a configuration, the effect of causing turbulence can be enhanced. The plurality of protruding portions55formed on the side face63of the car may be formed in a manner to extend obliquely downward from the front toward the rear of the car body30along the side face63of the car.

The automobile60includes, on the surface of the coating film50coated on the bonnet64and the front side face door66, the plurality of protruding portions55extending from the front toward the rear of the car body30as in the first embodiment. This allows the automobile60to obtain, on the surfaces of the bonnet64and the front side face door66, the effect of reducing frictional resistance. Thus, the plurality of protruding portions55extending in a direction from the front toward the rear of the car body30can be arranged on the front end61side of the car body30, and the plurality of protruding portions55including portions extending along a direction inclined with respect to a direction from the front toward the rear of the car body30can be arranged on the rear end62side of the car body30. In the case where the automobile60has such a configuration, it is possible to obtain the effect of reducing the frictional resistance on the front end61side of the car body30, and also to obtain the effect of reducing the boundary layer separation occurring rearward of the car body30by facilitating the occurrence of turbulence on the rear end62side of the car body30.

Further, the automobile60may also include, on the surface of the coating film50coated on the bonnet64and the front side face door66, the plurality of protruding portions55including portions extending along a direction inclined with respect to the direction from the front toward the rear of the car body30. When the automobile60has such a configuration, the effect of facilitating the occurrence of turbulence can be enhanced.

Modification of Second Embodiment

FIG.8is a plan view illustrating an example of an automobile according to a modification of the second embodiment. An automobile60illustrated inFIG.8differs from the automobile60according to the second embodiment illustrated inFIG.6in that the roof65further includes a protruding portion56extending from the front toward the rear (from the front end61toward the rear end62) of the car body30along the Y axis direction. Thus, when the automobile60includes a plurality of protruding portions55and56extending in different directions, the effect of facilitating the occurrence of turbulence can be enhanced.

Third Embodiment

FIG.9is a plan view illustrating an example of an automobile according to a third embodiment. An automobile60according to the third embodiment includes a plurality of protruding portions55extending along a direction inclined with respect to a direction from the front toward the rear of a car body30in a manner to be folded back across a plurality of bent portions57. That is, each of the plurality of protruding portions55includes the plurality of bent portions57and extends as a whole in a direction from the front toward the rear of the car body30while changing the direction to extend at the plurality of bent portions57. When the automobile60includes such a protruding portion55, the effect of facilitating the occurrence of turbulence can be enhanced.

Fourth Embodiment

FIG.10is a plan view illustrating an example of an automobile according to a fourth embodiment. In an automobile60according to the fourth embodiment, a plurality of protruding portions55extend from the front toward the rear on the front side (for example, the front end61side illustrated inFIG.3) of a car body30, and are bent at end portions55aand55bon the rear side (for example, the rear end62side illustrated inFIG.3) of the car body30. In the case where the automobile60has such a configuration, it is possible to obtain the effect of reducing the frictional resistance in the portion where the plurality of protruding portions55extend from the front toward the rear, and to obtain the effect of facilitating the occurrence of turbulence in the portion where the plurality of protruding portions55are bent. In particular, when the directions of the end portions55aand55bof the protruding portions55are different from each other as illustrated in the drawing, the effect of facilitating the occurrence of turbulence can be enhanced. AlthoughFIG.10illustrates only the plurality of protruding portions55formed on the roof65, the end portions on the rear side of the car body30may be bent in the same manner as the end portions55aand55b, for example, for the plurality of protruding portions55formed on the bonnet64illustrated inFIG.3, or the side face doors66and67illustrated inFIG.5.

First and Second Modifications

In each of the above embodiments, an example of the protruding portion55whose shape does not change in the length direction has been illustrated, but the embodiments are not limited to the example.FIGS.11A and11Bare plan views illustrating examples of automobiles according to the first and second modifications, respectively.

A protruding portion55illustrated inFIG.11Aincludes a first portion55cand a second portion55dhaving different sizes in the width direction (X axis direction) intersecting the length direction (Y axis direction) of the protruding portion55. On the other hand, a protruding portion55illustrated inFIG.11Bincludes portions having a different size in the height direction (Z axis direction) intersecting the length direction (Y axis direction) of the protruding portion55. In this manner, each protruding portion55may vary in shape in the length direction. When the automobile60has such a configuration, the effect of facilitating the occurrence of turbulence can be enhanced. AlthoughFIGS.11A and11Billustrate an example of the plurality of protruding portions55formed on the roof65or the bonnet64, the plurality of protruding portions55formed on side face doors66and67may similarly have different sizes in the width direction (Z axis direction) or the height direction (X axis direction) intersecting the length direction of the protruding portion55.

Third to Fifth Modifications

In each of the embodiments described above, the plurality of protruding portions55are illustrated as having substantially the same shape, but the embodiments are not limited to such a configuration.FIGS.12A to12Care cross-sectional views illustrating examples of automobiles according to the third to fifth modifications, respectively.

An automobile60illustrated inFIG.12Aincludes a protruding portion55ehaving a height direction (Z axis direction) size of h1and a protruding portion55fhaving a height direction (Z axis direction) size of h2(where h1>h2). An automobile60illustrated inFIG.12Bincludes a protruding portion55ghaving a width direction (X axis direction) size of w1and a protruding portion55hhaving a width direction (X axis direction) size of w2(where w1<w2). Further, an automobile60illustrated inFIG.12Cincludes a protruding portion55having a substantially arc-shaped cross-section, a protruding portion55jhaving a substantially quadrilateral cross-section, and a substantially triangle protruding portion55k. Thus, the plurality of protruding portions55may be different in shape from each other. When the automobile60has such a configuration, the effect of facilitating the occurrence of turbulence can be enhanced.

Sixth Modification

FIG.13is a cross-sectional view illustrating an example of an automobile according to a sixth modification. As illustrated inFIG.13, a plurality of protruding portions55may have an interval d between adjacent protruding portions55smaller than the height h of the protruding portion. When the automobile60has such a configuration, the effect of reducing frictional resistance between adjacent protruding portions55can be enhanced.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit thereof. For example, although each of the embodiments described above has been described as including the plurality of protruding portions55having similar shapes on the bonnet64, the roof65, and the side face doors66and67, for example, two or more of the embodiments and modifications may be suitably combined in the bonnet64, the roof65, and the side face doors66and67.

Although the car body30is illustrated as a flat surface in each of the above embodiments, the embodiments are not limited to such a configuration, and the car body30may be a curved surface or may be inclined.

Further effects and modifications can be readily derived by those skilled in the art. Thus, a wide variety of aspects of the present invention are not limited to the specific details and representative embodiments represented and described above. Accordingly, various changes are possible without departing from the spirit or scope of the general inventive concepts defined by the appended claims and their equivalents.