JPH0679512U - Mold for electronic parts - Google Patents

Abstract

(57) [Abstract] [Purpose] Resin that flows out from the cavity and flows along the lead frame etc. is accumulated and hardened, and it is removed all at once, facilitating the work of removing burrs. A mold for sealing and molding a lead frame (5) or an electronic component having a terminal projecting therefrom with a resin, wherein the lead frame (1) and the lower mold (2) constituting the mold are 5) or the portion where the terminals are arranged is provided with the resin reservoir (7).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a metal mold for electronic parts used when manufacturing coil parts such as a small transformer of a sealing molding type used in consumer electronic devices and other circuit parts.

[0002]

[Prior art]

 For example, there are various types of coil components such as small transformers, but there is one in which the coil body is molded by resin in order to improve the insulation and moisture resistance.

An epoxy resin is generally used as this resin. Then, at the time of encapsulation molding, the root of the lead frame that functions as a terminal is embedded in the coil bobbin, and the coil main body with the coil wound around the outer circumference of the winding body is set at a fixed position in the cavity of the mold. The epoxy resin was poured into the cavity through the gate of the mold, etc., to perform encapsulation.

[0004]

[Problems to be solved by the device]

 In this case, since only the outer circumference of the coil body is sealed and molded, as shown in FIG. 12, the portion of the lead frame 5 is out of the cavity 3, and the mold portion in which the lead frame 5 is arranged is A certain amount of clearance g is necessary due to the efficiency problem during work. Therefore, due to the pressure during molding, the epoxy resin a leaks from the cavity 3 toward the outer end of the lead frame 5 through the narrow clearance g as shown by the arrow, and the epoxy resin adheres to the lead frame 5 to cause burrs. There was a problem of becoming. In particular, when a liquid type epoxy resin is used, since it is liquid, it easily flows out from the cavity 3, and since this epoxy resin a has adhesiveness, it takes a lot of time to remove the burr that has occurred. there were.

That is, when burr adheres, defleshing is performed to remove it, but if the degree is high, the plating on the surface of the lead frame will be peeled off. Therefore, there is a problem that the peeling work is complicated.

This invention has been proposed in view of the above points, and its purpose is to make it possible to easily remove the resin flowing out from the cavity and adhering to the lead frame or terminals. It is to provide the mold.

[0007]

[Means for Solving the Problems]

 This invention is a mold for sealing and molding an electronic component having a lead frame 5 or a terminal provided with a protrusion, in which the lead frame 5 or the terminal of the upper mold 1 and the lower mold 2 constituting the mold are arranged. The above-described object is achieved by forming the resin reservoir portion 7 in the portion to be formed.

[0008]

[Action]

 In the present invention, the resin flowing out from the cavity 3 is not prevented from adhering to the lead frame 5 or the terminal as much as possible, and a clearance is unavoidable in the work, and the resin flows out from there, so the resin flows out. The resin reservoir 7 provided in the mold makes the resin so solidified that it is removed all at once.

[0009]

【Example】

 1 to 9 show an embodiment of the present invention. Thus, in FIG. 1, reference numeral 1 is an upper die that constitutes a mold, 2 is a lower die, and the upper die 1 and the lower die 2 form a cavity 3 having a predetermined shape inside. 1a is a gate for injecting a resin such as an epoxy resin into the cavity 3, 4 is a coil component such as a transformer body arranged in the cavity 3, 5 is its lead frame, 6 is after completion of sealing molding, It is an ejector pin that can move up and down to eject the coil component 4.

Reference numeral 7 denotes a resin reservoir portion that is a recess formed in the placement portion 3 a of the lead frame 5 of the upper die 1 and the lower die 2, respectively, and is located from the cavity 3 to the lead frame 5 side during the sealing molding. As shown in FIG. 3, the resin a that has flowed out is collected in the resin reservoir 7 and solidified.

As shown in FIG. 2, the resin reservoir 7 is provided near each long side of the cavity 3 formed in the upper mold 1 and the lower mold 2, and is arranged in the length direction thereof. The resin a, which is formed in the shape of a strip along the lead frame placement portion 3a, is filled in the cavity 3 at the time of encapsulation molding and leaks from the lead frame placement portion 3a as shown in FIG. It collects in 7 and hardens.

FIG. 4 shows a state in which a molded body 4A made of an electronic component such as a coil component or other circuit component molded with resin is taken out from the mold, and the unnecessary tie bar 5a ′ portion of the lead frame is As shown in FIG. 5, after molding the resin, it is first cut to leave only the terminal 5a. If the terminal itself is used in advance instead of the lead frame, the cutting work is unnecessary. FIG. 6 shows a side view thereof. In the drawings, 7A is a solid resin pool, and a dimensional relationship 1 between the terminal 5a protruding from the side surface of the molded body 4A and the resin pool 7A solidified on the outer side in the length direction of the terminal 5a. ₁ , L₂As l₁Is provided, and this gap l₁As a matter of course, resin as burrs is also attached to the part.

FIG. 7 shows an operation state in which the solidified resin reservoir 7A is removed by using the jig 8. The lower end of the jig 8 is provided with a protrusion 8a which can be inserted between the mold body 4A and the solidified resin reservoir 7A. The protrusion 8a is arranged in the region l ₁ and the jig 8 is manually or It is moved to the outside as shown by the arrow through an appropriate means such as a robot, and is forcibly removed by the shearing force.

[0014] In this case, although may also be divided integrally with resin a well resin reservoir 7A attached to a portion of the area l _1, most so as to be torn off from the resin a part of the area l ₁ resin The puddle 7A is removed, and a burr made of the resin a remains in the region l _1. However, this part does not pose any problem because the burr does not have to be removed so as to be a product, and there is no problem. In other words, the area l ₁ is set in advance in a range where there is no problem even if the product has burrs.

FIG. 8 shows an example in which a terminal 5a of an electronic component such as a coil component from which the resin reservoir 7A has been removed is bent into a substantially L shape and is of a surface mounting type with respect to a printed circuit board (not shown). Show.

Further, FIG. 9 shows an example in which the terminal 5a bent substantially at right angles is inserted into a terminal insertion hole (not shown) of the printed circuit board.

FIG. 10 shows a second embodiment of the present invention. In this example, a hole 7a is formed in the upper portion of the resin reservoir 7A, and the projection 8a of the jig 8 shown in FIG. 7, for example, is formed in this hole 7a. It is characterized in that it can be inserted and locked and that the resin reservoir 7A can be removed by moving the jig 8. The hole 7a can be easily formed by providing a protrusion (not shown) at a position corresponding to the hole 7a in a part of the upper mold 1 shown in FIG.

FIG. 11 shows a third embodiment of the present invention, in which a resin reservoir 7A is formed in the vicinity of the mold body 4A, which is located near the side of the cavity 3 of the mold shown in FIG. The resin reservoir 7 may be formed in the vicinity.

In the above embodiment, the case where the electronic component such as the coil component is mainly sealed and molded with the resin has been described, but it is needless to say that the present invention can be applied to other electronic components that require sealing and molding. Is.

[0020]

[Effect of device]

 As described above, according to the present invention, when an electronic component such as a coil component is put in a mold and molded, a resin reservoir 7 is positively formed in the terminal portion, and resin leakage from the cavity 3 is retained there. Since the resin puddle 7A is removed as a lump after molding, the resin puddle 7A can be easily removed, so that the removal operation becomes good.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a first embodiment of the present invention,
The mold closed state of a metal mold is shown.

FIG. 2 is a plan view of an essential part of a lower mold of a mold used in the present invention.

FIG. 3 shows an explanatory diagram of the operation of the present invention.

FIG. 4 shows a plan view of an electronic component taken out from a mold.

FIG. 5 shows a plan view of an electronic component from which an unnecessary lead frame portion is removed.

FIG. 6 is a side view of the same.

FIG. 7 is an explanatory diagram showing a state in which a resin reservoir of a terminal of an electronic component is removed.

FIG. 8 shows an example in which a terminal is bent into a substantially L shape to form a surface mount type electronic component.

FIG. 9 shows an example in which the terminals are bent substantially at right angles.

FIG. 10 is a second embodiment of the present invention.

FIG. 11 is a third embodiment of the present invention.

FIG. 12 shows an operation explanatory diagram of a conventional example.

[Explanation of symbols]

 1 Upper Mold 2 Lower Mold 3 Cavity 3a Lead Frame Arrangement 4 Coil Parts 4A Mold 5 Lead Frame 5a Terminal 5a 'Tie Bar 6 Ejector Pin 7 Resin Reservoir 7A Resin Reservoir 8 Jig 8a Protrusion

Claims (1)

[Scope of utility model registration request] 1. A mold for encapsulating a lead frame (5) or an electronic component having a terminal protruding from it by resin molding, wherein the leads of an upper mold (1) and a lower mold (2) constituting the mold. A metal mold for an electronic component, characterized in that a resin reservoir (7) is formed in a portion where a frame (5) or a terminal is arranged.