JP3296574B2 - Electronic component lead processing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of processing leads for an electronic component and an improvement of the processing apparatus, and more particularly, to a method of supplying a sealed lead frame to a predetermined position in a lead processing die and forming an outer lead. The present invention relates to a device that corrects a posture and sets the posture.

[0002]

2. Description of the Related Art In a sealed lead frame (that is, a lead frame in which an electronic component such as an IC chip mounted on the lead frame is molded with a resin material), the sealing resin solidifies. At the time of contraction or careless handling during handling by the worker,
The entire or part of the lead frame is wavy,
Further, the outer leads and the like are inclined and deformed in the lateral direction (see FIG. 1). Further, if such warpage or deformation occurs in the sealed lead frame, the pitch interval becomes uneven, and the transfer action to the subsequent process side is hindered, or the lead bending process is performed properly. There are problems such as being unable to do so.

In order to eliminate such warpage or deformation of the sealed lead frame, the structure of the lead frame itself may be improved as follows. For example (see FIG. 1), by adopting a configuration in which the tie bar 8 connected between the distal end portions of the outer leads 5 and the side frame 2 are separated, deformation of the outer leads 5 due to shrinkage of the sealing resin. The action is the side frame 2
To the side. Further, in this case,
Since the strength and shape retention of the outer lead 5 are problematic, the tie bar 8 at the tip of the outer lead and the tie bar at the tip of the outer lead in another adjacent product component unit, or The tie bar 8 at the tip of the outer lead and the end 9 of the lead frame are connected by a tie bar 10 having a narrow width and a required elasticity. Therefore,
In such a configuration of the lead frame, an effect of preventing deformation of the side frame due to the contraction action of the sealing resin can be expected as compared with the conventional one. Furthermore, since the engagement and disengagement of the pilot pin hole formed in the side frame and the pilot pin provided on the lead processing die side is not hindered, the sealed lead frame is securely positioned at a predetermined position in the lead processing die. It can be expected that the positioning can be easily performed, or it can be easily separated from the positioning.

However, the shrinkage of the sealing resin causes the entire outer lead 5 to be deformed in the longitudinal direction on the resin-encapsulated molded body (mold package) 4 side, or the entire outer lead 5 is deformed to the side frame 2. The state of deformation, such as tilt deformation in the lateral direction on the side, differs depending on the material of the lead frame, the resin material, the resin molding conditions, and the like. In addition, the operator often inadvertently deforms the outer lead portion and the like during handling. Therefore, for example, if the dam bar 6 is cut and removed (dam bar cutting step) in a state where the entire outer lead 5 is inclined and deformed in the lateral direction on the side frame 2 side, a punch for dam bar cutting is provided. However, this also cuts the outer lead 5 and causes a so-called undercut, which is a cause of molding failure.

For the purpose of preventing the formation of undercuts in the outer lead portion, for example, a guide member for correcting the pitch interval of the outer leads is provided at the tip of a punch for dam bar cutting. By inserting the member between the outer leads prior to the dam bar cutting step, the interval between the outer leads is forcibly corrected to a predetermined pitch interval, and thereafter, the dam bar between the outer leads is cut and removed. It is also conceivable to adopt a method.

However, the provision of such a punch for dam bar cutting provided with a correction guide complicates its mechanism and configuration, making its practical application extremely difficult and increasing the cost. There are drawbacks. In particular, in a product in which electronic components (chips) have a higher density and a higher number of pins (increase in the number of outer leads), the pitch between the outer leads is, for example, 0.3 mm to 0.4 m.
Since it is set as a very small interval called m, it is more difficult to use a large number of dam bar cutting punches provided with the above-mentioned correction guide under such conditions. There's a problem.

Therefore, the present invention supplies a sealed lead frame to a predetermined position in a lead processing die,
An electronic component lead processing method capable of reliably preventing the formation of undercuts in the outer leads during the dam bar cutting step by setting the posture of the outer leads in an appropriate state and automatically correcting the position. And a processing apparatus for the same.

[0008]

According to the present invention, there is provided a method for processing a lead of an electronic component, comprising: positioning a sealed lead frame at a predetermined position in a lead processing die; At the time of clamping of the lead processing mold, the entire outer lead in a state of being inclined and deformed is forcibly corrected to a predetermined position by a posture correcting member disposed on the mold, and then the sealed lead frame is formed. Cutting and removing the dam bar, and then bending the outer lead of the sealed lead frame into a predetermined shape, and then cutting and removing the tie bar at the end of the outer lead of the sealed lead frame. .

Further, the lead processing method for an electronic component according to the present invention comprises: a supply setting step of supplying and setting a sealed lead frame encapsulating the electronic component to a predetermined position in a lead processing die; A dam bar cutting step of cutting and removing the dam bar in, a lead bending step of bending the outer lead in the sealed lead frame into a predetermined shape, and a lead cutting step of cutting and removing the tie bar at the outer lead tip portion in the sealed lead frame. The method of lead-forming an electronic component, comprising the step of supplying and setting the sealed lead frame at a predetermined position of the lead processing die, and the mold of the lead processing die. The inclination is caused by the tightening pressure and the position correcting action of the posture correcting member provided on the lead processing die. Wherein the modifying forced to place the overall shape state of the outer lead.

The lead processing apparatus for an electronic component according to the present invention further comprises a supply setting mechanism for supplying and setting a sealed lead frame sealing the electronic component to a predetermined position in a lead processing die. And a dam bar cutting mechanism for cutting and removing a dam bar in the sealed lead frame, wherein the supply setting mechanism for the sealed lead frame is disposed on the lead processing die side. It is characterized by comprising a positioning member for a mounted lead frame, and a posture correcting member for correcting the projecting posture of the outer lead in a predetermined direction.

Further, the lead machining apparatus for an electronic component according to the present invention comprises:
In the sealed lead frame supplied and set in the lead processing die, the lead frame is disposed at a position where the outer lead tip comes into sliding contact with the tie bar side surface.

Further, in the lead processing apparatus for an electronic component according to the present invention, the outer lead protruding posture in the sealed lead frame is provided on the sliding contact engagement surface of the outer lead posture correcting member with the outer lead. Is provided with a required inclined surface for correcting posture, which guides in a predetermined direction.

[0013]

According to the present invention, first, the sealed lead frame is positioned at a predetermined position of the lead processing die by the positioning member, and then the lead frame is disposed on the die at the time of clamping the lead processing die. The entire outer lead in the state of being inclined and deformed by the posture correcting member is forcibly corrected to a predetermined position,
Since the dam bar is cut and removed in the corrected state, formation of an undercut in the outer lead portion can be efficiently and reliably prevented.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 shows a state in which the sealed lead frame 1 is supplied to a predetermined position in a lead processing die 12 by a required supply mechanism, and FIG.
It is a longitudinal cross-sectional view in a line. 1 and 2 illustrate a state in which the inclination deformation of the outer lead 5 in the sealed lead frame has not been corrected yet. FIG. 3 shows a state in which the entire outer lead 5 of the sealed lead frame 1 is forcibly corrected to a predetermined position by a posture correcting member 14, and FIG. 4 is a sectional view taken along line BB in FIG. FIG. 5 is a longitudinal sectional view taken along line CC of FIG. 3, respectively.

The above sealed lead frame 1 usually has
Side frames 2 juxtaposed on both sides, and tabs (not shown) for chip mounting formed between both side frames 2
And a tab lead or pinch 3 connecting the tab and both side frames 2, an inner lead (not shown) sealed inside the resin-sealed molded body 4, and an outer lead protruding from the outside. 5 and dam bars 6 connecting the outer leads 5 and the side frames 2 respectively.
And a dam portion 7 for molten resin which is located in a range between the dam bar 6 and both side frames 2 and which is located on the outer periphery of the resin molding 4, and a tip portion of each outer lead 5. And a tie bar 10 having a required width and a narrow width, which is connected between the tie bars 8 provided adjacent to each other in the longitudinal direction or between the tie bar 8 and the end 9 of the lead frame. A positioning hole 11 and the like which are formed on both side frames 2 and serve also as a hole for transferring the lead frame are provided.

In the sealed lead frame 1, the tie bar 8 connected between the distal ends of the outer leads 5 and the side frame 2 are separated from each other. Has been considered so that the deformation action of does not directly reach the side frame 2 side.
Accordingly, in the configuration of the sealed lead frame 1, the deformation of the side frame 2 due to the contraction action of the sealing resin is prevented. Therefore, a positioning hole (pilot pin hole) 11 formed in the side frame 2 and a positioning member (pilot pin) provided on the lead processing die 12 side.
Since the action of engaging and disengaging with the mold 13 is not impeded, the sealed lead frame 1 is set in the lower mold 121 of the mold.
122, and can be easily removed therefrom. However, the outer lead 5 in the sealed lead frame 1 illustrated in FIG. 1 is in a state where the entire outer lead 5 is inclined and deformed in the horizontal direction on the side of the side frame 2 due to the contracting action of the sealing resin described above.

On the upper die 123 side of the lead processing die 12 at the set position of the sealed lead frame 1, as shown in FIG. ing. The posture correcting member 14
It is sufficient that 14 is disposed at least in the portion of the lead processing die 12 where the dam bar is cut. Further, the respective posture correcting members 14 and 14 are respectively disposed at positions where the outer lead tips are in sliding contact with both side surfaces of the tie bar 8, and the respective posture correcting members 14. A required posture correction for guiding the posture of the outer lead 5 in the state inclined in the lateral direction to the appropriate direction (rightward in FIG. 2) is provided on the sliding contact engagement surface with the both side surfaces of the tie bar 8. Each of the inclined surfaces 141 is formed. The posture correcting members 14 are provided detachably with respect to the upper die 123. Therefore, the members are provided so as to be exchangeable and replaceable. In addition, the posture correcting member 14.1
At the lower die 121 side corresponding to the position 4,
Holes 124 to be fitted with 14 and 14 are provided respectively.

As shown in FIG. 5, a dam bar 6 for cutting and removing the dam bar 6 of the sealed lead frame 1 is provided on the upper die 123 side of the lead processing die 12 at the set position of the sealed lead frame 1. A cutting mechanism 15 is provided. Further, the dam bar cutting mechanism 15 is composed of an appropriate pressing member 151 of the outer lead 5 provided on the upper die 123 side and an appropriate punching member 152 for punching out the dam bar 6 for cutting and removing. ing. Further, the pushing member 152
On the lower die 121 side corresponding to this position, there is provided a hole 125 to be fitted with the push-out member 152. The hole 125
The holes also serve as discharge holes for discharging cut foreign matter such as dam bars to the outside of the lead processing die 12.

Hereinafter, lead processing of the sealed lead frame 1 in the above embodiment is performed as follows. First, when the upper and lower dies 123 and 121 of the lead processing die 12 are opened, the sealed lead frame 1 is securely placed at a predetermined position of the setting recess 122 of the lower die 121 via an appropriate supply mechanism. The supply setting process of the sealed lead frame 1 to be positioned at the position is performed. At this time, as described above, the sealed lead frame 1 is set by the engagement between the positioning hole 11 on the side frame 2 side and the positioning member 13 of the lower die 121. Although it is reliably positioned at the predetermined position of the recess 122, the inclined state of the outer lead 5 is not yet corrected. Therefore, the upper die 123 of the lead processing die is lowered, and the inclined surface 141 of the posture correcting member provided on the upper die is connected to the side surface portion of the tie bar 8 (in the illustrated example, the inclined surface of the left posture correcting member). 141 is slidably engaged with the left side surface of the tie bar 8). Next, in this state, the upper mold 123 is further lowered, and the upper and lower molds 123 and 121 are further lowered.
The sealed lead frame 1 is pressed between the upper and lower molds by the mold clamping pressure (see FIG. 4). At this time, the side portion of the tie bar 8 is pushed in an appropriate direction (to the right in FIG. 2) along the inclined surface 141 of the posture correcting member, so that the posture of the outer lead 5 is forcibly corrected. Will be. Further, at this time, the mold clamping pressure is applied to the upper and lower surfaces of the sealed lead frame 1 by the upper and lower molds 123 and 121, so that the wavy warping and the like in the sealed lead frame 1 can be corrected at the same time. Become. That is, in the supply setting step of the sealed lead frame, the sealed lead frame 1 is positioned at a predetermined position of the lead processing die 12, and the mold clamping pressure of the lead processing die 12 and the lead processing are performed. The deformed sealed lead frame can be forcibly and automatically corrected to an appropriate posture by the position correcting operation of the posture correcting member 14 disposed in the mold.

Since the outer lead posture correcting members 14 are arranged as a pair of right and left, the tie bar 8 is inclined to the right side, contrary to the one shown in FIG. However, the same posture correcting action by the right posture correcting member 14 can be applied to the outer lead.

Next, a dam bar cutting step of cutting and removing the dam bar 6 of the sealed lead frame is performed. The outer lead 5 of the sealed lead frame 1 that has undergone the above-described supply setting step is forcibly corrected for its inclined deformation state by the posture correcting action of the posture correcting members 14 (FIG. 3). And FIG. 4). Therefore, first, the upper mold 12
The upper surface of the outer lead 5 is pressed by the pressing member 151 of the dam bar cutting mechanism 15 provided on the third side, and then, in this state, the dam bar 6 is pressed and cut by the pressing member 152 (see FIG. 5). ), The cut dam bar is appropriately discharged to the outside through the lower die hole 125 fitted with the pushing member 152. Therefore, at this time, only the dam bar 6 is cut and removed.
2 can reliably prevent the formation of an undercut in the outer lead 5 portion.

Next, a lead bending step of bending the outer lead 5 of the sealed lead frame into a predetermined shape is performed, and then a lead cutting step of cutting and removing the tie bar 8 at the tip of the outer lead is performed. The outer lead 5 of the sealed lead frame 1 that has been subjected to the above-described supply setting step and dam bar cutting step is corrected so that its protruding posture is proper. Further, no undercut is formed in each of the outer leads 5. Accordingly, next, for example, a lead bending step of cutting the pinch 3, the tie bar 10, etc. to separate the product constituent unit from the sealed lead frame 1 and bending the outer lead 5 into a predetermined shape is performed. , The outer lead 5
May be performed by cutting a predetermined length position (cut line) and cutting and removing the tie bar 8 at the tip end.

The reason why the lead bending step of the outer lead 5 precedes the lead cutting step of cutting and removing the tie bar 8 at the tip of the outer lead is as follows. That is, it is preferable to apply a bending force to the outer lead 5 while leaving the tie bar 8 at the tip of the outer lead. This is because even if this bending force is applied as an external force that deforms each of the outer leads 5 by applying the bending force to the outer leads 5 equally to the entire outer leads 5, This is because the external force can be efficiently and reliably dispersed and absorbed through the tie bar 8. Therefore, for example, the inconvenience that occurs when the lead of each outer lead is bent after the cutting and removing of the tie bar 8, that is, the tip of each outer lead is individually lifted up, twisted or inclined in the lateral direction, and the It is possible to reliably prevent the disadvantage that the pitch intervals of the outer leads become uneven or that the tips of the outer leads come into contact with each other. In particular, such a lead processing means is effective and suitable for lead processing of a product such as a QFP type or an SOP type in which the number of pins is increased and the pitch between outer leads is set extremely small. Applicable.

Prior to the dam bar cutting step, a so-called resin cut (solidified resin) for removing a solidified resin (not shown) hardened in the dam portion 7 of the sealed lead frame. May be performed. This resin cutting step may be performed substantially simultaneously with the dam bar cutting step, if necessary. Further, since this kind of product constituent unit is a small part, the solidified resin in the dam portion 7 is also formed to be extremely small and narrow, so that the existence of the solidified resin may be practically negligible. Therefore, in such a case, the resin cutting step may be omitted. These processing procedures described above can be appropriately selected and adopted in consideration of, for example, the material of the sealed lead frame 1, the number of lead processing steps, and other circumstances.

The present invention is not limited to the above-described embodiment, but may be arbitrarily and appropriately changed and selected as necessary within a range not departing from the gist of the present invention. It is.

For example, in the above-described embodiment, D
Although an IP (two-way lead) type product has been described, it is apparent that the same can be applied to a QFP (four-way lead) type product and the like.

Further, a construction is provided in which processing dust, dust and other foreign substances generated during the above-described dam bar cutting step, resin cutting step, lead cutting step, etc. are forcibly removed by suction to the outside of the lead processing die. It may be added.

The positioning hole 11 is formed to have a slightly larger diameter so as to smoothly (roughly) engage with the positioning member 13. 1
4 may be used to more efficiently and reliably correct the posture of the outer lead 5 (positioning of the outer lead 5).

[0029]

According to the present invention, the position of the sealed lead frame is determined by the positioning member at a predetermined position in the lead processing die, and then the lead frame is disposed on the lead processing die when the die is clamped. According to the present invention, since the entire outer lead in the state of being inclined and deformed by the correcting member is forcibly corrected to a predetermined position, and the dam bar is cut and removed in the corrected state, according to the present invention, it is sealed. The present invention has an excellent practical effect that can efficiently and reliably prevent the above-described conventional adverse effect of forming an undercut in an outer lead portion of a lead frame.

Further, according to the present invention, the bending postures of the outer leads are not uniform, that is, the tips of the outer leads are individually lifted up, twisted or inclined in the lateral direction to change the pitch interval, or An excellent effect is obtained in that adverse effects such as contact between the distal ends of the outer leads can be efficiently and reliably prevented. For this reason, for example, after the product is formed, the lead posture correcting step of correcting the posture of each outer lead to an appropriate state individually using a dedicated lead posture correcting device can be omitted. It has a practical effect.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view showing a main part in a state when a sealed lead frame is supplied to a predetermined position in a lead processing die.

FIG. 2 is a partially cutaway longitudinal sectional view taken along line AA of FIG.

FIG. 3 is a partially cutaway plan view showing a main part of the sealed lead frame in which the entire outer lead is forcibly corrected to a predetermined position.

FIG. 4 is a partially cutaway vertical sectional view taken along line BB of FIG. 3;

FIG. 5 is a partially cutaway longitudinal sectional view taken along line CC of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealed lead frame 2 Side frame 3 Pinch 4 Resin molding 5 Outer lead 6 Dam bar 7 Dam 8 Tie bar 9 Lead frame end 10 Tie bar 11 Positioning hole 12 Lead processing die 121 Lower die 122 set Recess 123 Upper die 124 Hole 125 Hole 13 Positioning member 14 Posture correcting member 141 Posture correcting inclined surface 15 Dam bar cutting mechanism 151 Pressing member 152 Pushing member

Claims (5)

(57) [Claims] 1. A state in which a sealed lead frame is positioned at a predetermined position in a lead processing die, and is tilted and deformed by a posture correcting member disposed in the die when the lead processing die is clamped. Forcibly correct the entire outer lead to a predetermined position, then cut and remove the dam bar in the sealed lead frame, and then bend the outer lead in the sealed lead frame into a predetermined shape,
Next, a lead processing method for an electronic component, which comprises cutting and removing a tie bar at a tip portion of an outer lead in the sealed lead frame. 2. A supply setting step of supplying and setting a sealed lead frame sealing an electronic component to a predetermined position in a lead processing die, and a dam bar cutting step of cutting and removing a dam bar in the sealed lead frame. A lead bending step of bending an outer lead in a sealed lead frame into a predetermined shape, and a lead cutting step of cutting and removing a tie bar at a tip portion of the outer lead in the sealed lead frame, comprising: The supply setting step of the sealed lead frame positioned the sealed lead frame at a predetermined position of the lead processing die, and disposed the mold clamping pressure of the lead processing die and the lead processing die. By the position correcting action of the posture correcting member, the entire outer lead in the inclined deformed state is forcibly placed. A lead processing method for an electronic component, wherein the lead processing is performed at a fixed position. 3. A supply setting mechanism of a sealed lead frame for supplying and setting a sealed lead frame sealing an electronic component to a predetermined position in a lead processing die, and cutting and removing a dam bar in the sealed lead frame. An electronic component lead processing device having a dam bar cut mechanism, wherein the sealed lead frame supply setting mechanism includes a sealed lead frame positioning member disposed on the lead processing die side. And a member for correcting the position of the outer lead that corrects the projecting position of the outer lead in a predetermined direction. 4. A member for correcting the posture of the outer lead is provided at a position where the outer lead posture correcting member is slidably engaged with the tie bar side surface of the outer lead tip in the sealed lead frame supplied and set to the lead processing die. The lead processing device for an electronic component according to claim 3, wherein: 5. A required posture correcting inclined surface for guiding a projected posture of the outer lead in a sealed lead frame in a predetermined direction is provided on a sliding contact engagement surface of the outer lead posture correcting member with the outer lead. The lead processing apparatus for an electronic component according to claim 3, wherein the lead processing apparatus is formed.