JPH04287351A - Electronic component lead processing method and device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to leads for electronic components for separating each product constituent unit individually from a sealed lead frame, that is, a lead frame in which electronic components such as ICs are molded with resin. The present invention relates to improvements in processing methods and equipment, and particularly to methods for facilitating the cutting of tab leads that connect the lead frame and each product component.

0002

2. Description of the Related Art Conventional lead processing methods and apparatuses include a lead bending step of holding a sealed lead frame in a predetermined position in a lead processing mold and bending its outer leads into a desired shape; After the cutting process of cutting the parts and the lead bending process described above, each product structure is formed from the lead frame by cutting the tab lead which is the connecting part between the lead frame and each product structure (resin-sealed molded body of electronic parts). It separates the body into individuals. In addition, as a conventional lead processing method and apparatus, for example, there is a method in which the lead frame and each product component are separated in advance, and then lead bending is performed on the outer lead of each product component.

0003

By the way, in this conventional method and apparatus, the thickness of the resin-sealed molded body (mold package) of the electronic component is, for example, about 1 mm.
The following serious problems have been pointed out when processing the outer leads of thin products such as those listed below. That is, when the product separation step of cutting the tab lead described above is performed, the cutting force acts to pull out the tab inside the resin-sealed molded body through the tab lead. This will have an adverse effect on the electronic components and bonding wires in the product, and will cause cracks and defects in the resin-sealed molded product near the cut portion of the tab lead, impairing the moisture resistance and appearance of the product, resulting in a significant deterioration in quality.

[0004] Such a problem is caused by the fact that as electronic parts (chips) become denser and have more pins, the shape of the resin-sealed molded product itself becomes smaller. Together with this trend, this phenomenon is particularly noticeable in the case of products in which the thickness of the resin-sealed molded body is thin. In addition, in order to eliminate such disadvantages, it is conceivable to facilitate cutting of the tab lead by, for example, providing a pinch portion or the like at the cutting point of the tab lead in advance at the same time as punching and forming the lead frame itself. . That is, since the tabs and tab leads of large-sized products are usually formed in a wide shape, even if a pinch portion or the like is provided thereon, there is no problem such as a significant decrease in the strength of the tabs or tab leads. However, since tabs and tab leads of thin products inevitably have a narrow shape, when a pinch portion or the like is further provided thereon, the strength thereof is significantly reduced. Therefore, if a pinch section or the like is provided in advance at the cutting point of such a tab lead, the mold clamping force or There is a risk that the tab lead may be bent or broken from the pinched portion or the like due to external force during bending. For this reason, there is actually a processing problem in that the tab lead of a thin product cannot be provided with the above-mentioned pinch portion or the like.

[0005] Therefore, the present invention aims to ensure the strength of the tab lead required during the resin sealing molding process of electronic components and the lead bending process of outer leads, and also to prevent separation of the lead frame and each product component. The purpose is to reliably solve the above-mentioned conventional problems by facilitating the process.

[0006]

[Means for Solving the Problems] The electronic component lead processing method according to the present invention includes a lead holding step in which a sealed lead frame is held at a predetermined position in a lead processing mold; The method includes a lead bending step of bending the outer lead of the lead frame into a desired shape and a cutting step of cutting a predetermined portion of the lead frame, and after the lead bending step, the tab lead, which is the connecting portion between the lead frame and the product structure, is cut. A method for processing leads for electronic components, which performs a product separation process in which each product component is individually separated from a lead frame, and the tab lead is easily cut at required locations before the product separation process described above. It is characterized by performing a half-cutting process.

Furthermore, the electronic component lead processing method according to the present invention is characterized in that the above-described half-cutting step for the tab lead is performed simultaneously with the final lead bending step immediately before the product separation step.

Further, the electronic component lead processing method according to the present invention includes a lead holding step of holding a sealed lead frame at a predetermined position of a lead processing mold, and a lead holding step of holding the sealed lead frame at a predetermined position of the lead processing mold. A method for processing leads for electronic components, which includes a cutting step of cutting a portion, and a product separation step of separating each product component individually from the lead frame by cutting a tab lead that is a connecting portion between the lead frame and the product component. In the product separation step, a half cut is formed at a required location on the tab lead to facilitate cutting of the tab lead, and then the product structure is pressed in succession to the half cut, thereby separating the product structure. It is characterized by being separated from the lead frame.

Further, the electronic component lead processing method according to the present invention includes holding a sealed lead frame in a predetermined position in a lead processing mold, and forming a half cut for cutting the tab lead in the tab lead of the lead frame. A method for processing leads for electronic components, comprising a step of forming a half cut at a desired location of the tab lead using a required protruding blade portion that acts only on the tab lead portion. This is a characteristic feature.

Further, the electronic component lead processing apparatus according to the present invention is an electronic component lead processing apparatus equipped with a lead processing mold for a sealed lead frame, and includes half-cut processing means for tab leads of the lead frame. and a lead bending final processing means are disposed at the same processing location in the lead processing mold.

Further, the electronic component lead processing apparatus according to the present invention is an electronic component lead processing apparatus equipped with a lead processing mold for a sealed lead frame, and includes half-cut processing means for tab leads of the lead frame. In addition, the half-cut processing means is comprised of a required protruding blade portion disposed corresponding to the position and width of the tab lead.

0012

[Operation] According to the present invention, before the product separation step of cutting the tab lead, which is the connecting portion between the lead frame and the product component, for example, immediately before this product separation step, a half-cutting step is performed at the required locations of the tab lead. By doing this, it is possible to ensure sufficient strength of the tab lead required during the resin sealing molding process of electronic components and the lead bending process of the outer lead before the product separation process, and also the above-mentioned After the lead bending process, or
The product separation process performed before the lead bending process can be easily and reliably performed.

[0013]

[Embodiments] The present invention will be explained below based on embodiment figures. FIG. 1 shows the shape of the lead frame, FIGS. 2 and 3 show a sealed state using the lead frame, and FIG. 4 shows a state where required parts are removed from the sealed lead frame before lead bending processing. 5 to 8 show the lead bending process, FIGS. 9 and 10 show the final lead bending process and its main parts, FIG. 11 shows the lead processing mold, and FIGS. 13 shows another lead frame shape example.

The lead frame 1 includes side frames 2 arranged in parallel on both sides, a tab 4 for mounting a chip 3 formed between the side frames, and a tab lead connecting the tab and both side frames 2. 5 and outer lead 6
0 and an inner lead 61.
A tie bar (dam bar) 7 that connects each of the leads and between both side frames 2, and a tie bar 8 that connects each of the side frames 2 and the tip of each outer lead 60 are provided. It is being The inner leads 61 and the electrodes of the chip 3 are electrically connected via wires 9, and both side frames 2 have holes 1 for transporting or positioning the lead frame 1.
0 is formed.

The lead frame 1 described above is supplied and set at a predetermined position in a mold for resin sealing (not shown), and the chip 3, tab 4, tab lead 5, inner lead 61, wire 9, etc. in the lead frame are set. The resin material is encapsulated and molded, and the resin encapsulation range is determined in accordance with the cavity shape of the resin encapsulation mold. In addition, tie bars 7 are connected between each lead 6 and between both side frames 2, so that the molten resin material injected into the mold cavity is directed outward beyond the tie bars 7 and both side frames 2. leakage is prevented. Therefore, as shown in FIG. 2, the sealed lead frame has
The resin-sealed molded body 11 molded to correspond to the cavity shape of the mold for resin-sealed molding described above is integrated, and a dam part formed around the periphery of the resin-sealed molded body is Solidified resin 12 filled with a part of resin material and molded
are integrated.

The case where the sealed lead frame 1 is subjected to lead processing will be described below. First, a resin cutting process is performed to remove the solidified resin 12 that is integrated into the dam part of the lead frame, and at the same time or following the resin cutting process, the product is unusable. A tie bar cutting step is performed to cut and remove the necessary portions of tie bars 7 and 8 (see FIG. 4). At this time, since the tab leads 5 in the lead frame remain as they are, the product constituent unit 13 is connected to and supported by both side frames 2 via the tab leads. Note that the product constituent unit 13 itself is a small component, and therefore the solidified resin 12 in the dam portion is also formed to be extremely small and narrow, so the existence of this solidified resin 12 may be virtually ignored in some cases. However, in such a case, the resin cutting step described above may be omitted.

Next, a preliminary lead bending process is performed to bend the outer lead 60 at a substantially right angle (see FIGS. 5 and 6), and a final lead bending process is performed to bend the outer lead into a predetermined shape (see FIGS. 5 and 6). (See Figures 7 and 8).

FIGS. 9 and 10 show the state of the outer lead 60 during the final lead bending process using the lead processing mold 14. In this final lead bending process, the necessary parts of the tab lead 5, such as At the same time, a half-cut step is performed to form a half-cut 15 (see FIGS. 10 and 11) at a position along the shape and surface of the resin-sealed molded body 11 to facilitate cutting of the tab lead. As shown in FIG. 11, this half-cut 15 is formed by providing an appropriate protrusion 16 at a predetermined position on the mold surface of the lead processing mold 14, so that the tab lead 5 can be formed at a predetermined position during the final lead bending process. can be formed simultaneously. That is, the final processing means for lead bending (Fig.
0) and a half-cut processing means (projection 16) for the tab lead 5 are arranged at the same processing location in the lead processing mold 14 (see FIG. 10). ) Therefore, the final step of bending the leads and the half-cutting step of the tab leads can be performed simultaneously. Further, the location where the half-cut is formed can be selected as appropriate other than the location along the outer shape line of the resin-sealed molded body 11 or the surface thereof.

Next, the tab lead 5, which is the connecting portion between the lead frame 1 and the product component 13, is cut from the half cut 15, and each product component 13 is individually separated from the lead frame 1. Perform product separation process for That is, the half-cutting process for the tab lead 5 described above is performed immediately before this product separation process. The product separation step is carried out by appropriately punching out the half-cut 15 portions formed on the tab lead 5 using the lead processing die 14. Therefore, this product separation step can be easily and efficiently performed without requiring strong force. Therefore, it is possible to reliably prevent the cutting force of the tab lead 5 in the product separation step from acting as an external force that would pull out the tab 4 and the like inside the resin-sealed molded body 11 through the tab lead. The purpose of performing the above-mentioned half-cutting process on the tab lead 5 immediately before the product separation process is to increase the strength of the tab lead, which is required during the resin sealing process of electronic components and the lead bending process of outer leads. For example, if the strength of the tab lead can be ensured by the material of the lead frame, the half-cutting process described above does not necessarily need to be performed immediately before the product separation process.

The lead frame 1 shown in FIGS. 12 and 13 has an improved tab lead shape for the purpose of, for example, absorbing distortion and other external forces applied to the tab 4 at the tab lead 5 portion. However, it is clear that the same half-cutting process as described above can be performed on such a tab lead 5, and it is also clear that the tab lead 5 can be cut at any arbitrary position.

The embodiments shown in FIGS. 1 to 13 described above are as follows:
The sealed lead frame is held in a predetermined position in a lead processing mold, the lead frame is cut at a predetermined location, the outer lead is bent into a desired shape, and then,
The explanation has been given of a method in which each finished product component is individually separated from the lead frame by cutting the tab lead that is the connecting portion between the lead frame and each product component.
As mentioned above, when the lead frame and each product component that has not been subjected to lead bending are first cut and separated, and then the lead bending process is performed on the outer lead of each product component to form the finished product. Since the present invention can be implemented in the same manner also in FIG.
This will be explained based on the embodiment diagrams shown in FIGS. 16 to 16.

FIGS. 14 to 16 show another lead processing mold 1.
4 shows a product separation processing site in which each product component 13 is individually separated from the sealed lead frame 1 after cutting at a predetermined portion and removing unnecessary portions. In this product separation processing area, a lead holding process is performed in which the two side frames of the lead frame are held by the lead processing mold 14, and in this state, the product structure (in the case of the illustrated example, the product structure is A product separation step is performed in which the molded sealing body 11) is pressed to separate the product structure from the lead frame. However, the above-mentioned product separation step is performed at the same processing site as the half-cutting of the tab lead 5, which is performed almost simultaneously with the above-mentioned lead holding step.
The method includes pressing and separating the product structure, which is performed temporally consecutively to the half-cut. That is, as shown in FIG. 15, substantially simultaneously with the above-described lead holding step, the tab lead 5 is cut at a desired location by a half-cut processing means (protrusion 16) appropriately mounted on the lead processing mold 14. Forming a half cut 15 to facilitate
Next, by pressing the product structure (resin-sealed molded body 11) with the punching member 17 at the same processing site and temporally consecutively to the half-cut, a slight punching force is applied. The product structure 13 can be easily cut and separated from the lead frame 1. In this embodiment, the half-cutting of the tab lead and the pressing separation of the product structure are performed at the same processing site and in a temporally continuous manner. When transporting the lead frame from the previous stage to the next stage, as in the case where the product components are pressed and separated at the next stage of processing, the tab leads may deform and break at the half-cut part. This method does not interfere with the conveyance process, etc., and is therefore particularly advantageous when processing leads for thin products in which tab leads are provided in a thin or narrow shape. Note that each of the cut and separated product components 13 is individually subjected to a required lead bending process on its outer leads to become a finished product. Further, the structure is such that foreign matter such as processing debris and dust generated during the above-mentioned half-cut formation or punching of the product structure is sucked and removed in the punching direction of the product structure 13 (downward in FIG. 15). may be adopted.

FIG. 17 shows a case in which the above-mentioned half-cut processing means is configured to act only on the tab lead 5 portion. The half-cut processing means shown in the same figure is equipped with a protruding blade portion 18 arranged corresponding to the position and width (length) of the tab lead 5. When using such a half-cut processing means, the following steps are required. There are advantages such as: That is, when forming a half cut on the tab lead 5 using such a half cut processing means, it is necessary to efficiently prevent the half cut processing means from coming into contact with the solidified resin 12 at the left and right positions of the tab lead and being worn out. Can be done. In particular, since a thermosetting resin material is used in the sealing molding of this type of electronic component, it is conceivable that the half-cut processing means will wear out early. Therefore, if you prevent the wear and tear,
Since frequent replacement of the processing means can be omitted, the overall workability of lead processing can be improved and products with high quality and reliability can be formed, and the durability of the lead processing equipment can also be improved. There are advantages such as being able to

[0024] Note that the lead bending shape is not limited. For example, the shape of the outer lead may be approximately J-shaped (SOJ type), two-way lead (DIP type), or four-way lead (QFP type). In addition, the above-mentioned half-cut processing means (projection 1
6. The location of the protruding blade part 18) is the lead processing mold 1.
They may be provided oppositely on both opposing surfaces of 4. Further, instead of the half-cut processing means, for example, a processing means dedicated to forming half-cuts such as a punch may be provided. Furthermore, by adopting a configuration in which the half-cut processing means and the processing means dedicated to half-cut formation are detachably attached to the lead processing mold, it is possible to easily replace the processing means when the processing means wears out. It's okay.

[0025] The present invention is not limited to the above-described embodiments, but can be modified and selected as necessary and adopted without departing from the spirit of the present invention. It is.

[0026]

Effects of the Invention According to the present invention, by performing a half-cutting process on required parts of the tab lead before the product separation process of cutting the tab lead, it is possible to cut the tab lead in the resin sealing molding process of electronic parts or in the lead bending process of the outer lead. It is possible to secure sufficient strength of the tab lead as it is at times, etc., and to easily and reliably perform the product separation process that is performed after the lead bending process of the outer lead or before the lead bending process. be able to. Therefore, even when processing leads for thin products, the cutting force of the tab lead acts to pull out the tab inside the resin-sealed molded product to the outside through the tab lead, and the tab is mounted on the tab. Conventional problems such as adversely affecting electronic components and bonding wires, and causing cracks and defects in the resin molded product near the cut part of the tab lead, impairing the moisture resistance and appearance of the product and significantly reducing quality. It is said that it is possible to provide a lead processing method and apparatus for electronic components that can reliably solve the problems and improve the high quality and high reliability that are strongly required for this type of product. It has excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing an example of the general shape of a lead frame.

FIG. 2 is a partially cutaway plan view of the lead frame in a sealed state.

FIG. 3 is a front view of the sealed lead frame shown in FIG. 2;

FIG. 4 is a plan view showing a state in which required portions are cut and removed from the sealed lead frame before lead bending processing.

FIG. 5 is a plan view showing a lead bending process in which the outer leads of the sealed lead frame are bent at a substantially right angle.

6 is a longitudinal sectional front view taken along line AA in FIG. 5. FIG.

FIG. 7 is a front view showing a lead bending process in which the outer leads of the sealed lead frame are bent into a predetermined shape.

8 is a longitudinal cross-sectional side view taken along line BB in FIG. 7. FIG.

FIG. 9 is a schematic side view showing the state during the final lead bending process using the lead processing die.

FIG. 10 is a partially cutaway longitudinal side view showing an enlarged view of the final lead bending process using the lead processing die.

FIG. 11 is a longitudinal sectional side view showing the main parts of the lead processing mold.

FIG. 12 is a partially cutaway plan view showing another example of the shape of a lead frame.

FIG. 13 is a partially cutaway plan view showing another example of the shape of a lead frame.

FIG. 14 is a partially cutaway longitudinal side view showing the main parts of another lead processing mold.

15 is a partially cutaway longitudinal side view showing an enlarged main part of the lead processing mold shown in FIG. 14; FIG.

16 is a partially cutaway longitudinal side view showing an enlarged main part of the lead processing mold shown in FIG. 14; FIG.

FIG. 17 is a partially cutaway perspective view showing the positional relationship between another half-cut processing means and a tab lead.

[Explanation of symbols]

1 Lead frame 2 Side frame 3 Chip 4 Tab 5 Tab lead 6. Lead 60 Outer lead 61 Inner lead 7 Tie bar 8 Tie bar 9 Wire 10 Hole part 11 Resin-sealed molded body 12 Solidified resin 13 Product component unit 14 Lead processing mold 15 Half cut 16　Protrusion-shaped part 17　Pushing member 18 Protruding blade part

Claims (6)

[Claims] 1. A lead holding step for holding a sealed lead frame in a predetermined position of a lead processing mold, a lead bending step for bending the outer leads of the lead frame held by the lead holding step into a desired shape, and a lead frame. and a cutting step of cutting a predetermined portion of the
A method for processing leads for electronic components, which includes, after the lead bending step, a product separation step in which each product component is individually separated from the lead frame by cutting a tab lead that is a connecting portion between the lead frame and the product component, A method for processing leads for electronic components, characterized in that, before the product separation step described above, a half-cutting step is performed at required locations on the tab lead to facilitate cutting of the tab lead. 2. The electronic component lead processing method according to claim 1, wherein the half-cutting step for the tab lead is performed simultaneously with a final lead bending step immediately before the product separation step. 3. A lead holding step for holding the sealed lead frame in a predetermined position of a lead processing mold, a cutting step for cutting a predetermined portion of the lead frame held by the lead holding step, and the lead frame and the product. A method for processing leads for electronic components, comprising a product separation step of cutting tab leads, which are connection parts with components, and separating each product component individually from a lead frame, wherein the product separation step is performed in accordance with the requirements of the tab leads. An electronic component characterized in that a half cut is formed at a location to facilitate cutting of the tab lead, and then the product component is separated from the lead frame by continuously pressing the product component. lead processing method. 4. A method for processing leads for electronic components, comprising the steps of holding a sealed lead frame in a predetermined position in a lead processing mold, and forming a half cut for cutting the tab leads in the tab leads in the lead frame. A method for processing a lead for an electronic component, wherein the half-cutting step includes forming a half-cut at a desired location on the tab lead using a predetermined protruding blade portion that acts only on the tab lead portion. 5. A lead processing apparatus for electronic components comprising a lead processing mold for a sealed lead frame, wherein a half-cut processing means for tab leads of the lead frame and a final lead bending processing means are arranged in the lead processing mold. A lead processing device for electronic components, characterized in that the device is disposed at the same processing site in a mold. 6. A lead processing apparatus for electronic components comprising a lead processing mold for a sealed lead frame, further comprising half-cut processing means for the tab lead of the lead frame, and the half-cut processing means is configured to cut the tab lead of the lead frame. 1. A lead processing device for electronic components, characterized in that the device is comprised of required protruding blade portions arranged corresponding to the position and width of the lead.