JPH06182272A - Jig for coating - Google Patents

Abstract

PURPOSE:To enable the application of a coating material without having parts remained without being coated and unequal coating by integrally providing projections having elasticity and the outer peripheries approximately equal to or slightly larger than the inner peripheries of the holes of coating surfaces at the same intervals as the pitches of the holes on a base plate. CONSTITUTION:This jig 1 is provided with the columnar projections 3 on the base plate 2. The base plate 2 and the projections 3 are integrally molded of a fluororesin-based rubber material. The projections 3 are formed slightly larger than the bores of the holes (for example, push button holes) provided on the material to be coated (for example, casing 4 of a telephone receiver) to which the outer peripheral diameters thereof are fitted. The projections 3 are fitted from the front surface 6 side of the casing 4 toward the side of the rear surface 7 which is the coating surface and thereafter, a conductive coating material is sprayed to the inside surface of the casing 4. As a result, the coating material is applied thereon up to the peripheral edges of the holes 5 without having the parts remained without being coated and without the unequal coating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention particularly relates to a coating jig used for forming a conductive coating film for shielding electromagnetic waves on the inner surface of a plastic casing of electronic equipment.

[0002]

2. Description of the Related Art A small portable communication device having a casing made of plastic, a display, an OA device,
In electronic devices such as control devices and special electronic musical instruments that are driven by a CPU or a similar method, in order to prevent external clock pulse and high frequency radiation / leakage,
Alternatively, an electromagnetic wave shield is generally provided to prevent the entry of external interference radio waves represented by high frequency noise from similar devices. Examples of the method include a method of attaching a shield plate to the inner surface of the casing, a method of forming a conductive coating on the inner surface of the casing, and a method of imparting conductivity to the entire casing.

Among the above methods, as a method of forming a conductive coating on the inner surface of the casing, there is a method of spraying a conductive coating or the like on the inner surface of the equipment casing to form a conductive coating. To form a conductive coating film on the inner surface of the casing, which is provided with a large number of holes for operation buttons, ventilation holes for heat dissipation, holes for keyboards and displays, etc., by spraying as shown in FIG. The coating jig 100 is used.

This jig 100 comprises a cover plate 101 for masking, which is slightly larger than a hole provided on a coated surface, and a cover plate 1.
01 and a connecting bar 103 for connecting the leg 102. The holding bar 104 of the connecting bar 103 is used to hold a coating object 105 as shown in FIG. It is possible to form a coating film on the surface 106 side without spraying the paint into the hole 107 by spraying the paint on the painted surface 106 after covering the hole 107 from the painted surface 106 side with the cover plate 101. You can do it.

[0005]

However, the jig 1 described above is used.
The coating method using 00 has the following problems.
That is, in recent years, as electronic devices have become faster in digital operation speed, the clock pulse frequency has become higher, and the possibility of radiation and leakage of high-frequency noise to the outside has increased at the same time. Although it is necessary to apply the coating so that there is no unpainted portion or uneven coating on the surface, in the coating method using the jig 100, as shown in FIG. 6, the cover plate 101 is caught around the hole (opening) 107. There is a problem that the unpainted portion 108 of a part is inevitably formed and uneven coating 109 is formed on the shadowed portion of the leg portion 102 and the connecting bar 103.

Further, although the jig 100 is repeatedly used, the paint adheres to the leg portion 102 and the connecting bar 103 by applying the coating material several times, and the leg portion 102 and the connecting bar 103 are coated.
Becomes thicker, and uneven coating 109 is more likely to occur. Therefore, it is necessary to wash with a solvent several times, and in order to improve production efficiency, a plurality of jigs must be prepared at all times, which also causes an increase in production cost.

In view of such circumstances, it is an object of the present invention to provide a coating jig which can be coated uniformly and easily without any uncoated portion or coating unevenness.

[0008]

In order to achieve such an object, a coating jig according to the present invention is provided with a projection having elasticity and an outer circumference that is substantially the same as or slightly larger than the inner circumference of the hole. The structure is integrally provided on the base arranged on the back side of the coating surface at the same interval as the pitch of the holes. In the above-mentioned configuration, if the protrusion of the jig has elasticity, the elastic material is preferably one that is not corroded by a solvent such as paint, and for example, a fluororesin rubber material is preferable.

If the hole is relatively small, the protrusion is
It is preferable to make the diameter a little larger than the hole diameter and to provide a hollow portion in the protrusion so that the compression force from the inner wall of the hole can be controlled. On the other hand, when the hole is relatively large, it is preferable that the hole has a size that substantially matches the hole diameter and that the hollow portion is not provided.

[0010]

According to the above construction, when the jig is attached to the coated object so that the protrusion fits into the hole from the back side of the coated surface and the coating material is sprayed on the coated surface, the elastic force of the protrusion causes the protrusion. Since the side wall surface is pressed against the inner peripheral surface of the hole in a watertight manner, the paint does not seep into the hole. Moreover, since there are no obstacles around the holes, it is possible to coat the periphery of the holes without leaving an uncoated portion or uneven coating.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings showing the embodiments thereof. FIG. 1 shows one embodiment of a coating jig according to the present invention when viewed obliquely from above, and FIG.
[FIG. 2] is a plan view of a state in which the jig of FIG. 1 is attached to the casing of a telephone receiver, which is a painted object, as viewed from the painted surface side.

As shown in FIG. 1, the jig 1 includes a base 2
Cylindrical projections 3, 3 ... 3 are provided on the upper side, and the base 2 and the projections 3 are integrally formed of a fluororesin rubber material. Further, as shown in FIG. 3, the projection 3 has a hole (push button hole in this embodiment) 5, which is provided in a coated object (in this embodiment, the casing 4 of the handset) with which the outer diameter is fitted. The inner diameter of 5 ... 5 is slightly larger than that of the inner diameter, and the recessed hole 31 is provided to form a hollow portion for giving flexibility.

As shown in FIGS. 2 and 3, the jig 1 is fitted with the projection 3 from the front surface 6 side of the casing 4 toward the rear surface 7 side, which is the coating surface, and then on the inner surface of the casing 4. If the conductive paint is sprayed, there are no obstacles around the hole 5 as in the conventional case, so that the paint can be applied to the peripheral edge of the hole 5 without leaving unpainted or uneven coating.

Further, although this jig 1 was used for continuous coating several ten times, the amount of paint adhered to the jig 1 was small. Therefore, it is possible to improve the production cost without the trouble of washing with the solvent every several times as in the conventional case. The coating jig according to the present invention is not limited to the above embodiment. For example, although the hole 5 is circular in the above embodiment, it may be any other shape such as a quadrangle or a triangle. The size of the holes 5 does not have to be constant.
Further, the painted surface may be not only the inner surface of the casing but also the front surface side. Furthermore, in the above-mentioned examples, the coating composition is used for the conductive paint, but it can be used for the undercoat treatment and the primer treatment when the conductive coating is formed by plating or vapor deposition.

[0015]

As described above, in the coating jig according to the present invention, the protrusion having the elasticity and the outer diameter which is substantially the same as or slightly larger than the inner diameter of the hole is arranged on the back side of the coating surface. Since it is integrally provided on the base at the same interval as the pitch of the holes,
When a jig is attached to the painted object so that the projection fits into the hole from the back side of the painted surface and the paint is sprayed onto the painted surface, the elastic force of the projection causes the side wall surface to contact the inner surface of the hole. The water-tight contact prevents paint from seeping into the holes. Moreover, since there are no obstacles around the holes, it is possible to coat the periphery of the holes without leaving an uncoated portion or uneven coating.

Therefore, if the conductive film is formed by using this jig, it is possible to obtain an electronic device having a high electromagnetic wave shielding effect. Moreover, the maintenance of the jig is easy and the production cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a coating jig according to the present invention.

FIG. 2 is a plan view showing a state where the jig of FIG. 1 is mounted on a casing of a telephone handset.

FIG. 3 is a cross-sectional view illustrating a state in which a jig is attached to a casing.

FIG. 4 is a perspective view showing an example of a conventional coating jig.

5 is a cross-sectional view showing a state in which the jig of FIG. 4 is attached to a coated object.

FIG. 6 is a plan view showing a state of a coated surface when coating is performed using a conventional jig.

[Explanation of symbols]

 1 Coating jig 2 Base 3 Protrusion 4 Handset casing (painted object) 5 Hole 7 Back surface (painted surface)

Claims (1)

[Claims] 1. A coating jig used for coating a molded article having a large number of holes formed on a coating surface, the jig having elasticity and having an outer diameter approximately equal to or slightly larger than the inner diameter of the hole. A coating jig, wherein the projections are integrally provided on a base arranged on the back side of the coating surface at the same intervals as the pitch of the holes.