JP2530273Y2 - Lead frame - Google Patents

Description

[Detailed description of the invention]

[Industrial applications]

The present invention relates to a lead frame for forming a lead wire or an electrode of an electronic component by sandwiching an element at a connection end.

[Prior art]

As shown in FIG. 6, electrodes 17 and 17 (one electrode 17 is
Hiding behind. ), And a ceramic electronic component in which leads 12 ′, 12 ′ are led out from the electrodes 17, 17 is used. In the manufacturing process of this electronic component, as shown in FIG. 5, a U-shaped linear lead 12 having a crossed end portion is used to attach a plurality of ceramic elements 16, 16,.
Of leads (hereinafter, referred to as taping leads) taped with a paper tape 13 or the like at equal intervals. By using this taping lead, the ceramic elements 16, 16,... Are sandwiched therebetween by the resilience of the intersecting tips 14, 15, of the leads 12, 12, and the leads 12, 12,.
And the electrodes 17, 17 on the main surface of the ceramic element are soldered. Subsequently, as shown by an imaginary line in FIG. 6, after the ceramic element is coated 18 with a resin or the like,
The middle part of the lead 12 is cut. Thus, a radial lead type ceramic electronic component in which the pair of lead wires 12 ', 12' is led out in parallel is obtained.

[Problems to be solved by the invention]

However, when a ceramic electronic component is manufactured using the above-described taping lead, only a so-called radial lead type electronic component can be manufactured. For example, a so-called surface on which a chip-shaped electronic component is mounted on a circuit board. Cannot be implemented. Furthermore, the tip of the lead 12
The force holding the ceramic element between 14 and 15 is weak, and before fixing by soldering, the ceramic element 16 shifts and leads
It may fall off between the twelve tips 14,15.
In particular, when the ceramic element 16 is a disk-shaped element having a small diameter, such as that used for a ceramic capacitor or a varistor, the ceramic element 16 is likely to fall off, which causes a reduction in product yield. In addition, since the leads are held by the tape, a step of attaching the leads to the tape at regular intervals is required, and this step requires a lot of trouble and a long time. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a lead assembly which can be easily adapted to surface mounting, can securely hold a ceramic element, and can be easily manufactured.

[Means to solve the problem]

The present invention proposes the following lead frame for the above-mentioned problem. That is, a connecting band 1 and a plurality of sets of lead portions 2 arranged in parallel with the connecting band 1 are formed by a flat metal plate.
3 and connecting pieces 10, 10... Connecting the leads 2 and 3 to the connecting band 1 at a predetermined interval, and a pair of leads 2 and 3 derived from the adjacent connecting pieces 10 and 1 In a set of the lead portions 2 and 3, the lead portions 2 and 3 are formed by cutting a middle portion of the connecting pieces 10, 10... Of a band-shaped metal frame having a uniform width into a crank shape. The lead frame has connection ends 6, 7 which are formed in an uneven shape such that their tips are butted and fitted to each other.

[Action]

Connection end portions 6 of the lead portions 2 and 3 of the lead frame,
When the ceramic element 8 is sandwiched by 7, the connection ends 6, 7 of the leads 2, 3 are flat, so that the ceramic element 8 can be stably sandwiched. Especially,
The connection ends 6, 7 of the leads 2, 3 are cut into the middle of the connecting pieces 10, 10,. In addition, since the ceramic elements 8 are formed in a concave and convex shape so as to fit each other, the small ceramic element 8 can be stably held, and the ceramic element 8 can be prevented from shifting or falling off. As a result, the ceramic element 8 can be prevented from falling off before soldering, and the yield of ceramic electronic components formed using the lead frame is improved. Also, the lead portions 2 and 3 are formed by cutting a strip-shaped frame having a uniform width into a crank shape so that the connection end portions 6 at the tips thereof can be cut.
7, the connection ends 6, 7 at the leading end are also the same width or smaller than the other parts of the leads 2, 3.
For this reason, even the small ceramic element 8 can be clamped, and the connection end portions 6 and 7 are less likely to bend when clamping. In addition, since the ladder-shaped lead frame is punched out and at the same time the middle part of the connecting pieces 10 and 10 of the frame part for forming the leads 2 and 3 is cut into a crank shape, the punching die has a simple shape. Is fine. Therefore, since the lead frame can be easily punched, the frame can be manufactured with high yield.

【Example】

Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied to a ceramic capacitor. In FIG. 1, reference numeral 1 denotes a connecting band of a lead portion, and holes 4, 4,... For positioning are formed in the connecting band 1 at regular intervals.
The connecting band 1 can be fed in the longitudinal direction by the track feeder. The connecting pieces 10, 10 are orthogonal to the connecting band 1 at regular intervals.
Are led out at equal intervals, and lead portions 2 and 3 are drawn out from both ends of the connecting pieces 10 and 10 in parallel with the connecting band 1. A pair of leads 2, 3 derived from adjacent connecting pieces 10, 10 constitute a set of leads 2, 3 between the connecting pieces 10, 10. This pair of lead portions 2, 3
Are separated by cutting an intermediate portion of a strip-shaped metal frame having the same width as a whole, and the cut ends are abutted between the connecting pieces 10, 10 to form connection ends 6, 7. It is configured. As shown in FIG.
The tip of one lead 2 is formed in a concave shape, and the tip of the other lead 3 is formed in a convex shape that fits into the recess. In this case, when the lead frame is punched out of the metal plate, a continuous strip-shaped metal frame to be the lead portions 2 and 3 is punched in a crank shape in the middle of the connecting pieces 10 and 10 and the lead portions 2 and 3 on both sides are punched. Then, the cut ends are formed as the connection ends 6 and 7. As shown by imaginary lines in FIGS. 1 and 3, a ceramic body 8 is sandwiched between the connection ends 6 and 7 of the pair of leads 2 and 3. In this state, the connection ends are soldered to the electrodes on both surfaces of the ceramic body 8, and
Is covered with an insulating paint, and the lead portions 2 and 3 are cut at the locations indicated by the lines A and B in FIG. Thus, a so-called axial lead type electronic component in which the leads 2 and 3 are led out from both sides of the ceramic body 8 is formed. Or,
The insulating resin 9 is formed in a prismatic or cylindrical shape,
2 is cut at the points A and B, and as shown in FIG. 2, the cut side is bent inward in a U-shape. Electronic components can be configured. Such a lead frame can be manufactured by punching a thin metal plate by, for example, etching or pressing. The thickness of the metal sheet as a material is determined by the shape and dimensions of the ceramic element a to be clamped by the lead portion 2 in consideration of the strength and elasticity of the lead portions 2 and 3. When the lead frame having the above configuration is used for manufacturing a ceramic capacitor, displacement of the ceramic body 8 hardly occurs, and the lead frame itself can be easily formed. As the ceramic body 8, for example, a dielectric ceramic body used for a ceramic capacitor or a ceramic body used for a varistor or thermistor is generally used. The connection ends 6 and 7 of the leads 2 and 3 are the third ends.
In addition to the shape shown in the figure, for example, a shape as shown in FIG. 4 can be mentioned.

[Effect of the invention]

As described above, according to the present invention, even a small ceramic element can be securely held, a lead frame which can be easily manufactured can be obtained, and a lead wire or a surface mount of a radial lead type electronic component can be supported. Since a lead portion that can be formed as an electrode of a chip-shaped electronic component is obtained, the form of the electronic component can be diversified.

[Brief description of the drawings]

FIG. 1 is a plan view of a lead frame showing one embodiment of the present invention, FIG. 2 is a perspective view showing an example in which a chip-type electronic component is formed using the lead frame, seeing through an exterior resin,
FIG. 3 is an enlarged plan view showing the tip of the lead portion of the lead frame, FIG. 4 is an enlarged plan view showing another example of the tip of the lead portion of the lead frame, and FIG. FIG. 6 is a front view of a radial lead type electronic component manufactured by using the assembly of the lead wires as seen through an outer covering. 1 ... connecting band, 2, 3 ... lead part, 6, 7 ... lead connection end part, 8 ... ceramic body

Claims (1)

(57) [Scope of request for utility model registration] 1. A connecting band (1) formed of a flat metal plate and a plurality of sets of leads (2) and (3) arranged in parallel with the connecting band (1) and these leads (2) and (3). Connecting pieces (10) for connecting to the connecting band (1) at predetermined intervals,
(10).., And a pair of leads (2) and (3) derived from the adjacent connecting pieces (10) and (10) constitute a set of leads (2) and (3). In the lead frame, the lead portions (2) and (3) are formed by cutting an intermediate portion of the connecting pieces (10), (10)... Of a band-shaped metal frame having a uniform width into a crank shape. A lead frame, characterized in that connection ends (6) and (7) are formed in an uneven shape such that their tips abut each other and fit each other.