JP2003200436A - Method for manufacturing holding plate used for coating external electrode of electronic part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the tackiness of a plastic molded object to prevent the adhesion of grinding refuse to a holding plate or the clogging of a grinding material with the grinding refuse. <P>SOLUTION: The method for manufacturing the holding plate 1 comprising a process (a) for inserting a core material plate 5 having rigidity comprising a metal or the like into a mold and molding and processing a silicone rubber molded object 7 to obtain the holding plate 1, a process (b) for heat-treating the holding plate 1, a process (c) for grinding the surface of the silicone rubber molded object 7 of the holding plate 1 and a process (d) for irradiating the ground holding plate 1 with radiation. Radiation used in the irradiation of the holding plate 1 is preferably ultraviolet rays. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a holding plate used when an external electrode is applied to and formed on an end of a small electronic component such as a chip capacitor or a resistor.

[0002]

2. Description of the Related Art One of the methods for applying external electrodes to the ends of small electronic components such as chip capacitors and resistors is to form a plastic with a large number of holes having a diameter smaller than the maximum cross-sectional dimension of the electronic component. It is known to use a holding plate containing a material (Japanese Patent Publication No. 62-20685). Push a small diameter hole open to accommodate electronic components,
It is elastically held by the elasticity of the plastic material. This holding plate has rigidity such as metal, is formed of a plastic material, and has a core material hole having a diameter slightly larger than the diameter of the elastic hole having a diameter slightly larger than the maximum sectional size of the electronic component to be held. The core plate provided is inserted into a mold, and a plastic material such as silicone rubber is injected into the mold for molding.

In order to provide elastic holes in the holding plate, the core material plate is inserted into a mold in which a large number of molding pins corresponding to electronic parts are embedded, and the core material preliminarily provided on the molding pins and the core material plate. The method of filling the gap between the holes and the plastic material is generally used, and after molding, in order to flatten the hole burrs of the plastic molded product and the unevenness of the plastic molded product surface so as not to impair the external electrode coating function. In addition, a method of polishing the surface of the plastic molded body is generally used. When coating and forming electrodes on small electronic components such as chip capacitors, holding plates that are stored and transferred by stacking flat portions are sequentially separated and small electronic components are inserted into elastic holes of the holding plate. It is delivered to the electrode coating line. After the electrodes are applied and formed collectively for each holding plate, the electronic components are pushed out by the same number of push pins as the number of elastic holes, and are dropped and collected at one time. Electrodes may have electrodes formed on both ends thereof by coating.

[0004]

This holding plate is
Most of both surfaces are covered with a plastic material, and the surface of the plastic material is flattened by polishing.Therefore, when the electrodes are applied and formed on top of each other in the plane direction, the holding plates are firmly attached by adhesion. In some cases, the holding plate may become stuck and it may be difficult to separate the holding plates individually, the transport machine may not operate smoothly, and in some cases, troubles such as stopping may occur. Further, when the component is dropped by the push pin after the electrode application, there is a problem that the electronic component sticks to the back surface of the holding plate due to the adhesiveness of the plastic material and the static electricity of the electronic component, and the electronic component does not fall. The present invention is
The present invention has been made in view of the above problems, and provides a method of manufacturing a holding plate used for coating external electrodes of electronic components, which enables improvement of separability from a set state of the holding plate and smooth recovery of all products. It is a thing.

[0005]

A method of manufacturing a holding plate according to the present invention for achieving the above object has a rigidity of metal or the like,
An electronic component formed by integrally molding a silicone rubber molded body having a large number of elastic holes capable of elastically holding an electronic component in the thickness direction on a core plate having a core material hole previously formed in the thickness direction. A method of manufacturing a holding plate used for applying an external electrode, comprising: (a). A step of inserting the core plate having rigidity such as metal into a mold and molding a silicone rubber molded body to obtain a holding plate; (a). A step of heat-treating the holding plate, (c). A step of polishing the surface of the silicone rubber molded body of the holding plate,
(D). Irradiating the polished holding plate with radiation. It is preferable that the radiation species to be irradiated is ultraviolet light.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As a means for reducing the adhesiveness of a silicone rubber molding on the surface of a holding plate, the present inventor can achieve the above object by irradiating the surface of the silicone rubber molding with radiation. The inventors have found the present invention and reached the present invention. A holding plate used for coating external electrodes of the electronic component of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view in which a part of a holding plate used for coating external electrodes of electronic components is cut away. FIG. 2 is a partially enlarged sectional view of FIG. FIG. 3 is an explanatory view showing one aspect of hole burrs produced by molding of a silicone rubber molded body.

A holding plate 1 used for coating external electrodes of an electronic component of the present invention has a collar-shaped portion 2 on the periphery thereof, and a plurality of core material holes 4 are formed in a flat portion 3 connecting the center of the collar-shaped portion 2. The core plate 5 and the core hole 4 continuously covering the both sides of the flat portion 3 in the vertical direction, and the elastic hole 6 is formed substantially in the center of the core hole 4.
And a silicone rubber molded body 7 having The surface of the silicone rubber molded body 7 is basically flush with the upper and lower surfaces of the collar-shaped portion 2 of the core plate 5. The material of the core plate 5 having rigidity such as metal is not particularly limited, but carbon steel, aluminum alloy, magnesium alloy, nickel alloy and the like are mentioned as preferable materials, and in terms of workability and operability. Therefore, aluminum alloy is particularly preferable.

As described above, the core material plate 5 has the collar-shaped portion 2 on the periphery thereof, and the plurality of core material holes 4 are formed in the flat portion 3 connecting the centers of the collar-shaped portion 2. From the plate-shaped body having the thickness of the collar-shaped portion 2, the flat portion 3 that connects the centers of the collar-shaped portion 2 can be cut out, and a plurality of core material holes 4 can be formed at desired positions. Alternatively, the brim portion 2 and the flat portion 3 may be separately prepared and assembled and joined by welding or the like. The surface of the core plate 5 is preferably subjected to a primer treatment in advance in order to enhance the adhesiveness with the silicone rubber. As a material of the silicone rubber molded body 7 as an elastic body, a commonly used material such as a millable type silicone rubber or an addition type liquid silicone rubber can be used.

A holding plate 1 is formed by molding a silicone rubber molded body 7 as an elastic body on the flat portion 3 of the core plate 5.
And To this end, a core plate 5 having a large number of core holes 4 is inserted at a desired position in a mold having a large number of pins for forming elastic holes 6, and a silicone rubber composition is injected to mold and solidify. To do. As a molding method, a molding method such as compression molding, transfer molding or injection molding can be used. Whichever molding method is adopted, a die suitable for each may be used. The molded and solidified holding plate 1 is subjected to a heat treatment in order to reduce the amount of low-molecular siloxane remaining in the silicone rubber and stabilize the physical properties. The heat treatment is performed by maintaining the temperature at 120 ° C to 230 ° C for 30 minutes to 8 hours in a dryer.

If the heat treatment is carried out at 120 ° C. for 30 minutes or less, the low-molecular siloxane cannot be removed efficiently, and 230
The above range is desirable because the curing deterioration occurs at 8 ° C. × 8 hours or more. This heat treatment is common in the processing of silicone rubber. Holding plate 1 formed by injecting a silicone rubber composition
In many cases, hole burrs 8 are formed around the elastic hole 6 as shown in a typical example in FIG. 3, and the surface of the silicone rubber molded body 7 is not necessarily smooth. Therefore, the holding plate 1 that has undergone the heat treatment process has its surface polished. As the polishing method, it is performed to have the smoothness that is the basic performance of the holding plate, so it is possible to use surface grinding, milling grinding, lapping, etc. that can remove hole burrs and minute irregularities that occur when processing silicone rubber. The method is useful.

The surface layer surface of the heat-treated and abraded silicone rubber molded body 7 is still somewhat sticky. Due to the adhesiveness of the surface layer of the silicone rubber molding 7, the holding plates may stick to each other when stacked. In order to reduce the adhesiveness of the surface layer surface of the silicone rubber molded body 7, the polished holding plate 1 is irradiated with radiation. Radiation species that can make tackiness reduction possible in principle include ultraviolet rays, electron beams, and gamma rays. Among them, it is most preferable to use ultraviolet rays, which have excellent apparatus scale and operability. The UV irradiation device used is commercially available and there is no problem.UV lamp, ozone cleaning lamp, unit cooler, air exhaust device, catalyst device are the basic components, and batch type, continuous conveyor type, etc. should be used. You can

[0012]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. [Example 1] 1. Aluminum core vertically 180 for the core plate
mm, thickness 10 mm, cut 2 mm each from both sides in the thickness direction, leaving 10 mm in the outer circumference, and make a core plate with 1500 mm 2 holes each having 2 mmφ holes in the length of 30 rows. did.

2. Next, 1 mmφ forming pin arranged so as to be in the same position as the core hole position of the core plate
Insert the core plate into a mold equipped with 500 pieces, and liquid silicone rubber KE-1950-50A / B
(Shin-Etsu Chemical Co., Ltd., trade name) was injected by an injection molding machine, and the silicone rubber was cured at 120 ° C. for 10 minutes. 3. Next, this was placed in an oven and heat-treated at 200 ° C. for 4 hours. 4. Further, the surface of the holding plate was ground using a cylindrical grinder to remove surface irregularities, burrs and the like. 5. This is an ultraviolet irradiation device (I Graphics Co., Ltd.)
Manufactured) and irradiated with ultraviolet rays. As irradiation conditions,
High-pressure mercury lamp 350W x 3 lights, irradiation distance 10mm,
The irradiation time was 3 minutes on one side, and both sides were irradiated.

Comparative Example 1 The same steps as in Example 1 were carried out except that the ultraviolet irradiation step in Example 1 was not performed.
A holding plate of Comparative Example 1 was produced.

Since the plates produced by the examples have no surface tackiness, the holding plates do not stick to each other even if they are stacked on the electrode coating device in the plane direction.
It was smoothly separated and transported. Even after applying the electrodes, when the electronic parts were dropped by the push pins, they could all be collected without sticking to the back surface of the plate. On the other hand, the plate manufactured according to the comparative example did not separate when it was stacked on the electrode coating device in the plane direction, and thus the line was stopped once. Also, the drop recovery rate of electronic parts after applying electrodes is about 95.
%, And 5% became defective in the state of being attached to the back surface of the plate.

[0016]

According to the method for manufacturing a holding plate according to the present invention, by reducing the tackiness of the silicone rubber molding on the surface of the holding plate, (1) prevention of troubles due to stoppage of conveying equipment, and (2) holding plate The effects of improving the separability from the set state and (3) improving the collection rate of parts can be obtained. Therefore, it is possible to provide a holding plate that solves the problems of the conventional holding plate manufacturing method.

[Brief description of drawings]

FIG. 1 is a schematic perspective view in which a part of a holding plate used for coating an external electrode of an electronic component is cut away.

FIG. 2 is a partially enlarged sectional view of FIG.

FIG. 3 is an explanatory view showing one aspect of hole burrs generated in a molding process of a silicone rubber molded body.

[Explanation of symbols]

1: Holding plate (used for coating external electrodes of electronic parts) 2: Collar 3: Flat part 4: Core hole 5: Core plate 6: Elastic hole 7: Silicone rubber molding 8: Hole burr

Claims (2)

[Claims] 1. A core material plate having rigidity such as metal and having core material holes preliminarily provided in the thickness direction, having a large number of elastic holes capable of elastically holding electronic components in the thickness direction. A method for manufacturing a holding plate used for applying an external electrode to an electronic component, which comprises integrally molding a silicone rubber molded body,
(A). A step of inserting the core plate having rigidity such as metal into a mold and molding a silicone rubber molded body to obtain a holding plate; (a). A step of heat-treating the holding plate, (c). A step of polishing the surface of the silicone rubber molded body of the holding plate, (engineering). A method of manufacturing a holding plate used for coating an external electrode of an electronic component, comprising the step of irradiating the polished holding plate with radiation. 2. The method for manufacturing a holding plate used for coating an external electrode of an electronic component according to claim 1, wherein the radiating species to be irradiated is ultraviolet light.