JPH0294699A - Electronic part with leg and its manufacture - Google Patents

Abstract

PURPOSE:To realize stabilization of a mechanical size and electric performance of a product by making a diameter or a width of a leg not exceeding 2mm and a length three to five times the diameter or the width. CONSTITUTION:Among circuit parts mounted on a wiring substrate, a leg 31 connected to a shield block is formed in one-piece structure through die-cast method to acquire a precision electronic part with a leg of good high frequency characteristics. That is, in an electronic part which is casted and formed in one-piece structure by a metal material and has a shield section 32 electrically connected to the leg 31, a diameter or a width of the leg 31 is made at most 2mm and the length three to five times the diameter or the width. According to this constitution, a highly weather-proof part of good quality which has little distortion during formation, and little variations in plate thickness can be acquired.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a small precision component having a shield portion that is electrically connected to a leg portion, used in electronic equipment, precision machinery, etc., and a method for manufacturing the same. .

These components are particularly useful as high frequency components.

[Prior Art 1] In recent years, with the widespread use of printed wiring boards for electronic device parts, a method has been adopted in which electronic circuits are formed by mounting the parts on a wiring board and soldering them.

Some of these electronic device parts require electrical shielding, and are assembled on a shield block, covered with a shield case, and mounted on a board. Conventionally, this shield block was made by cutting a metal block or molded from plastics such as epoxy resin, polyester resin, nylon resin, ABS resin, etc.
The surface is chemically plated.
In order to mount and solder the components assembled on these shield blocks onto a wiring board, it was necessary to separately attach legs that were inserted into holes in the wiring board to serve as terminals.

However, with this terminal, the hole diameter of the wiring board is usually 0.3~
Since the diameter is in the range of lIl■, the diameter is 1 mm or less, and
It is necessary to have an elongated shape whose length is three times or more the diameter.

Therefore, as shown in Figure 9, a metal plate with a thickness of 1 mm+ or less is punched into the required shape, bent to make the legs, and then integrally molded with plastic parts, or separately processed thin pins are cut. It was used as a circuit component by soldering it to processed parts.

[Problems to be solved by the invention] However, attaching thin pins to a block by cutting is a complicated process, and shield blocks molded from plastic and chemically plated suffer from molding distortion, especially molding. It is not suitable for precision parts because of the large shrinkage afterward. It is difficult to apply chemical plating to a sufficiently thick and uniform thickness, resulting in uneven plating thickness and easy peeling. When used as high-frequency circuit equipment, dimensional stability and shielding properties may be affected. There was a problem 6 again.

In order to attach it to the wiring board, create the legs separately as shown above.1. : It was necessary to use solder (single piece or integral molding) in combination with .

On the other hand, if you try to integrally cast a thin pin-shaped connecting terminal board at the same time as the shield block using the die-casting method, it will be difficult to obtain the desired shape if the pin diameter is 2+i+s or less and the length is three times the diameter or more. is difficult. That is, the shape of the pin tends to collapse, many cavities occur, and the function as a terminal pin is often impaired, making it impossible to obtain an economically viable yield.

Therefore, the first mold (fixed mold) l for molding the leg portion and the shield block main body were molded as shown in the cross-sectional view of the manufacturing mold for the leg portion ε---led block in Fig. 6. Molding is performed using a mold that is combined with a second mold (movable mold) 2, and hot water is introduced from the gate 8. After cooling, the second mold 2 is pulled up and the molded shield block 5 is formed.
1 is pushed with a dowel pin IO to remove the gold and take it out. In this case, the pin type cavity 5 of the first mold l
In No. 3, a mold with a relatively large draft angle on the pin is used so that the hot water can enter well and the mold can be easily removed.

However, even when such a cavity is used, as shown in FIG. 7, cavities and through-holes are significantly generated in the part 0.3 to l++- from the tip of the leg part 54, and this part is broken in the subsequent process. Also, in those that are nickel plated after die casting, the plating solution remains and causes corrosion, resulting in a product yield as low as 40 to 60%, making it impossible to put it to practical use.

Further, when a pin with a large taper is attached to the board 55, there is a large gap between the pin and the through hole of the board 55 as shown in FIG. 8, and soldering is likely to cause defects due to poor soldering.

[Means for solving the problem] Among the circuit components mounted on the wiring board, the legs that connect to the shield block are integrally molded using a die-casting method, thereby creating a leg-mounted electronic device that is precise and has excellent high-frequency characteristics. The present invention is directed to an electronic component having a shield part integrally cast from a metal material and electrically connected to one leg part, An electronic component with legs, in which the diameter or width of the legs is 2III18 or less and the length is 3 to 5 times the diameter or width, and a method for manufacturing the same, that is, the legs are integrally cast and formed from a metal material, and the legs are integrally formed with the legs. A method for manufacturing an electronic component having an electrically conductive shield portion, the method comprising: inserting a pin or a protruding piece into a punch hole or groove of a first mold in which a through hole for molding five legs is formed; a step of forming a mold by the first mold and a mold for molding the shield portion; a step of introducing hot water into the mold and die-casting the mold; The mold is separated from the second mold, and the tip of the leg is pressed by further inserting the pin or protrusion inserted into the hole or groove of the first mold to produce the molded product. The present invention provides a method for manufacturing an electronic component with legs, characterized by comprising a step of releasing the leg from the mold.

[Function] By integrally molding electronic components with legs using the die-casting method, the resulting component has less distortion during molding, and as a result, the mechanical dimensions and mounting position of the component are stable, and it is resistant to high frequencies. The plating to reduce the surface resistance can be thin, so there is less variation in the plating thickness and the adhesion strength of the plating is high. Excellent weather resistance and quality guaranteed.

In the present invention, any metal material that can be die-cast can be used as the material metal to be die-cast, but zinc, zinc alloy, aluminum, etc. are usually used.

[Example 1] Figures 3(a) to 3(c) are assembly diagrams of a high-frequency relay component using an electronic component with legs according to an embodiment of the present invention. A shield block 32 is integrally die-cast, and a relay mechanism (not shown) is placed on the shield block 32. The relay mechanism (not shown) is inserted into the pin hole 34 of the bottom case 33 (C), and the cover case (B) is inserted into the pin hole 34 of the bottom case 33 (C). 35
It can be assembled by covering it. FIG. 4 shows an example in which a plate-shaped leg portion 31' is provided as a modification of the terminal. FIGS. 5A, 5B, and 5C are a side view, a front view, and a perspective view of the assembled relay parts, where 31 is a leg and 36 is a lead terminal of the relay.

In manufacturing the above-mentioned high frequency relay component, the shield block with legs is integrally die-cast. An example of a mold structure used for molding such a component with legs is shown in FIG.

In the mold shown in FIG. 1, a piercing hole 4 is provided at the tip of the leg cavity 3, and a filling pin 5 is inserted therein. FIG. 2 is an enlarged cross-sectional view of the tip of the cavity 3. The cavity 3 has a slight draft angle, and the hole-filling pin 4 is movable up and down with respect to the hole. It is fixed to a pin block 6 and fixed in a position forming the tip of the one leg cavity 3 by a positioning block 7 as shown in FIG.

As shown in FIG. 2, the filler pin 5 preferably has a gap of 0.1 to 0.3 m11 with the punched hole 4. This gap prevents the formation of cavities by allowing gases generated when the molten metal solidifies during casting and air caught in the molten metal to escape, and on the other hand, the molten metal does not enter this gap due to surface tension.

Further, the filling pin 5 may have a draft angle opposite to that of the leg cavity 3, as shown in FIG. In this case, a gap of 0.1 to 0.3ffi11 between the hole filling pin 5 and the punching hole 4 allows the filling pin 5 to be pushed up by nmm when taking out the two-die punched product.

In addition, the punch hole 4 does not necessarily have to have the same diameter as the leg cavity 3 (it may be smaller than the diameter of the tip of the leg. Particularly when the leg to be die-cast is plate-shaped, The hole provided at the bottom has a shape such as a plate shape or a pin shape, and a protruding piece corresponding to the above-mentioned hole-filling pin is inserted according to the shape.

In the method for manufacturing an electronic component with legs, the die-casting of the leg part is performed as follows.

A filler pin 5 fixed to a push pin block 6 is inserted into the punch hole 4 of the leg cavity 3 of a first mold (fixed mold) l having a leg cavity 3, and the push pin block 6 is fitted with a coil spring 6. The filler pin 5 is pressed against the stopper 7, and the tip of the filler pin 5 is positioned at the tip of the leg cavity.

A second mold (movable mold) 2 having a cavity for molding the main body of the shield block 9 is used as a molding mold in accordance with the first mold 1, and after preheating the mold to 300 to 400°C, °C molten zinc alloy is injected into the piston (not shown)
It is introduced into the mold from the gate 8 by 0.05 to 0.
It fills with gold in 2 seconds.

The mold is then cooled, and the gas generated when the zinc alloy solidifies escapes through the parting line of the first mold and the second mold and the gap between the punch hole 4 and the filler pin 5.

Before the mold is cooled and the molded shield block 9 is taken out, the second mold 2 is first lifted, and at the same time the push pin block 6 is pushed up, the hole filling pin 5 is further inserted, and the leg The molded shield block is easily removed from the mold by the dowel pin lO of the second mold 2, which helps the shield block 11 to separate from the leg cavity 3.

[Effects of the Invention] In the electronic device component of the present invention, the shield portion and the leg portion are integrally die-cast, so the shape is precise, there is no distortion, and the plating thickness is lower than that of plastic molded products. Since it can be made thinner, there is no variation in plating thickness, and the mechanical dimensions and electrical performance of the product are stable.

Furthermore, the die-cast molding according to the present invention allows the legs to be integrally molded, and since punch holes are provided in the mold, defects such as cavities do not occur at the tips of the five legs, improving product yield. Further, since the filler pin inserted into the punched hole can be used as a knock pin for the molded leg, the thin leg does not remain in the cavity, and the inside of the cavity can be easily cleaned. Furthermore, since the draft angle of the legs can be made smaller, it is possible to mold fairly straight legs, and when the resulting parts are mounted on a board, there are few land gaps and soldering is easy, and terminals can be easily soldered. has high strength.

The electronic component of the present invention is suitable as a shield component with low skin resistance, and has stable mechanical dimensions, so it is particularly excellent as a component of a high frequency transmission circuit.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the structure of a die-casting mold for manufacturing an electronic component according to the present invention, and FIG. 2 is a cross-sectional view showing an example of a punch hole and a filler pin of the leg cavity shown in FIG. 1. FIG. 3 is an assembled diagram of a high frequency relay which is an embodiment of the component of the present invention, FIG. 4 is a perspective view of another embodiment of the component of the present invention seen from the terminal side, and FIG. FIG. 3 is a side view, a front view, and a perspective view of a high-frequency relay assembled according to the figures. FIG. 6 is a cross-sectional view of a die-casting mold without punching holes, and FIG. 7 shows an example of the tip end of a leg formed by the mold shown in FIG. FIG. 8 is a cross-sectional view showing a state in which the large tapered legs are attached to a board. FIG. 9 is a perspective view of an insert leg part made of sheet metal and used for plastic molded parts. l...-first gold, 2...second mold, 4.
...Punching hole, 5--Pin, 9--Molded product,
3 l... Leg part, 32... Shield part.

Claims (2)

[Claims] (1) An electronic component that is integrally cast and formed from a metal material and has a shield part (32) that is electrically conductive with a leg part (31), and the diameter or width of the leg part (31) is 2.
An electronic component with legs whose length is 3 to 5 times the diameter or width and is less than mm. (2) A method for manufacturing an electronic component having a shield part (32) that is integrally cast and formed from a metal material and that is electrically conductive with a leg part (31), the method including a through-hole punch for forming the leg part. a step of inserting a pin (5) or a protruding piece into the punching hole (4) of the first mold (1) in which the hole (4) is formed; and the first mold (1) and the shield part. A step of forming a mold with a second mold (2) for molding (32), a step of die-casting by introducing hot water into the mold, and a step of die-casting the first mold (1). By separating the second mold (2) and further inserting the pin (5) or protruding piece inserted into the hole (4) or groove of the first mold (1), the leg can be removed. Press the tip of the part (31) to form the molded product (9
).