JP4337685B2 - Resin sealing substrate - Google Patents

Description

  The present invention relates to a resin-sealed substrate in which electronic components mounted on a circuit pattern substrate made of a thin metal plate are sealed with an insulating resin layer.

  Conventionally, as this type of resin-encapsulated substrate, for example, the one described in Patent Document 1 is known.

  The “circuit configuration electronic component” described in Patent Document 1 is provided with a circuit pattern and a connection terminal integrally formed by punching a metal thin plate, and after soldering an electronic element on the circuit pattern, the circuit pattern and The electronic element is sealed with an insulating resin, so that there is no need to separately provide a circuit board and a circuit pattern, and the electronic element can be reliably protected by the resin.

  On the other hand, on the resin-sealed board, it is often the case that the electronic component mounted on the circuit pattern board is sealed with an insulating resin layer to manufacture the main body of the resin-sealed board, and then the electronic component is mounted later on the main body. is there.

  In the case of such a resin-sealed substrate, a through hole b for mounting a post-installed electronic component is formed in the circuit pattern substrate a in advance as shown in FIG. 10, and the electronic component is formed by the insulating resin layer c. In order to prevent the insulating resin layer c from covering the through hole b, a tapered recess d is formed in the insulating resin layer c on the upper surface and the lower surface side of the through hole b.

These recesses d are tapered so that the surface side of the insulating resin layer c has a large diameter and gradually decreases toward the through hole b, and a mold (not shown) for molding the insulating resin layer c and a circuit pattern are formed. In order to prevent the insulating resin layer c from covering the through hole b even if the insulating resin layer c is thermally shrunk between the substrates a, the diameter on the through hole b side of the recess d is equal to the through hole b. Therefore, a shelf-like portion e is generated around the through hole b of the circuit pattern substrate a sealed with the insulating resin layer c.

  When mounting a retrofitting component on the main body of a resin-sealed substrate formed by sealing an electronic component mounted on the circuit pattern substrate a with an insulating resin layer c, the component mounting apparatus or the operator manually installs the retrofitted electronic component. The component lead f is inserted into the through hole b of the circuit pattern substrate a. Since there is a shelf-like portion e around the through-hole b, the tip of the lead f hits the shelf-like portion e as shown in FIG. Sometimes.

  In such a case, correction work is performed so that the tip of the lead f is aligned with the through hole b while moving the post-installation electronic component in the horizontal direction. However, when mounting a retrofit component using a component mounting apparatus, the tip of the lead f , The tip of the lead f is deformed and cannot be inserted into the through hole b.

  In addition, when mounting the retrofitted electronic component manually, it takes time to insert the lead f of the retrofitted electronic component into the through hole b, resulting in poor workability.

  On the other hand, the resin-encapsulated substrate on which the mounting of the post-attached electronic component is completed solders the lead f of the post-attached electronic component inserted into the through hole b in the flow soldering process.

  At this time, as shown in FIG. 12, soldering is performed by spraying a solder jet g from the back side of the resin-encapsulated substrate. However, if the diameter of the recess d is reduced in advance in the same manner as the recess d on the mounting side of the post-installed electronic component. The solder jet g does not reach the through hole b in which the lead f is inserted, and as a result, there arises a problem that the lead f and the circuit pattern a cannot be soldered.

  The present invention has been made in order to improve such a problem, and an object of the present invention is to provide a resin-encapsulated substrate in which post-installed electronic components can be easily mounted and solder defects are less likely to occur.

The resin-sealed substrate of the present invention comprises a circuit pattern substrate formed by punching a metal thin plate to form a circuit pattern, a land having a through hole for mounting an electronic component, and the front and back surfaces of the circuit pattern substrate. A resin-sealed substrate comprising an insulating resin layer that seals an electronic component mounted on a circuit pattern substrate by coating, and is provided on the side of the circuit pattern substrate on the side to be a post-attached electronic component mounting surface A tapered first recess having a large diameter on the surface side and having a large diameter on the surface side and gradually decreasing in diameter toward the through hole side for mounting the retrofitted electronic component, and the periphery of the through hole by providing the first recess in a formed ledge, sets the diameter of the small-diameter portion of the first recess such that the width of the ledge is 1/2 or less of the lead diameter retrofitted electronic components, tapered The angle of inclination of the inner peripheral surface of the concave portion 1 is set to approximately 5 degrees, and furthermore, the surface side has a large diameter on the insulating resin layer provided on the solder surface side of the front and back surfaces of the circuit pattern substrate, Retrofit sequentially tapered such that the diameter to the through hole side for mounting electronic components, and the inclination angle of the inner circumferential surface, characterized in that the formation of the second recess which is set to approximately 45 degrees.

  With the above configuration, when mounting a retrofit electronic component, the lead tip of the retrofit electronic component is guided by the inner peripheral surface of the recess, and can be inserted into the through hole without hitting the shelf-like portion around the through hole. In addition, it is possible to efficiently mount the retrofitting electronic component in a short time, and the tip of the lead is not deformed by the shelf, so even when mounting the retrofitting electronic component automatically using the component mounting device It will not be impossible to implement.

Moreover, since the lead | read | reed of the mounted electronic component mounted by the said structure is supported by the internal peripheral surface of a 1st recessed part, even when the thickness of a circuit pattern board | substrate is thin, the self-supporting state of the mounted electronic electronic component is unstable It will never be.

Further, with the above-described configuration, when soldering the post-installed electronic component by the flow soldering process, the solder jet does not sufficiently reach the through hole and the soldering failure does not occur, so that the reliability of the flow soldering is improved.

Resin sealing substrate of the present invention, in a time of mounting a plurality of electronic components retrofitted on the circuit pattern, in the case where the through-holes with each other for mounting the lead of each post with the electronic components are close corresponds to each through hole The second recesses formed in this way are formed so as to be continuous with each other , and thin portions or ribs are formed between the through holes adjacent to each other .

According to the above configuration, even when lands for mounting the post-installed electronic components are close to each other, the second recess having an inclination angle of the inner peripheral surface of approximately 45 degrees can be formed. Is not generated, and there is no fear that the through holes are short-circuited by the solder due to the thin portions or ribs formed between the through holes.

Resin sealing substrate of the present invention, circuitry pattern forms a rectangular recess in the insulating resin layer covering the tie bars provided so as not to separate to expose the tie bar, and reach data Iba rectangular shape recess A thin portion is formed, and the tie bar is punched and cut leaving the thin portion.

With the above configuration, when soldering a post-installed electronic component with flow solder, the solder does not blow up from the punched hole to the upper surface side of the resin-encapsulated substrate, so that the solder blowing height can be set high. Therefore, the reliability of flow soldering can be improved.

  According to the resin-encapsulated substrate of the present invention, when mounting the post-attached electronic component, the lead tip of the post-attached electronic component can be inserted into the through hole without hitting the shelf-like portion around the through hole. The component mounting operation can be performed efficiently in a short time, and the solder jet flow sufficiently reaches the through-hole so that no soldering failure occurs, so that the reliability of flow soldering is improved.

  Embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view of the top surface (mounting surface of a post-installed electronic component) side of the resin sealing substrate, FIG. 2 is a plan view of the bottom surface (solder surface) side, and FIG. 4 is an enlarged cross-sectional view taken along line BB in FIG. 2, FIG. 5 is an enlarged view taken along a circle C in FIG. 2, FIG. 6 is a cross-sectional view taken along line DD in FIG. FIG.

  The main body 1 of the resin-encapsulated substrate includes a circuit pattern substrate 2 formed by punching a metal thin plate into a circuit pattern shape, and an insulating resin layer 4 that encapsulates the electronic component 3 mounted on the circuit pattern substrate 2. .

  When the circuit pattern substrate 2 is formed by punching a thin metal plate, the circuit pattern substrate 2 is formed with a land for soldering an electronic component 3 such as an IC, a chip resistor, a capacitor, or a diode, or a circuit pattern (both not shown). ) A diver 2a that is temporarily connected so as not to be separated from each other, and a land 2b for soldering 5 to the post-installed electronic portion, etc. are formed, and each of the lands 2b has an electronic component 3 and a post-installed electronic component 5 A through hole 2c for inserting the lead 5a is formed.

  The front and back surfaces of the circuit pattern substrate 2 are covered with the insulating resin layer 4 in a layered manner, so that the electronic components 3 mounted on the circuit pattern substrate 2 are sealed.

  The insulating resin layer 4 that covers the front and back surfaces of the circuit pattern substrate 2 is formed using a mold (not shown) composed of an upper mold and a lower mold. A cavity is formed at a position that matches the mounted electronic component 3 so as to surround the periphery of the electronic component 3.

  Further, convex portions (not shown) for forming tapered concave portions 4a and 4b are formed on the upper and lower surfaces of the lands 2b so that the lands 3b for mounting the retrofitted electronic components 5 are not covered with the insulating resin layer 4. And the lower mold respectively.

  The recesses 4a and 4b provided on the upper and lower sides of each land 2b are formed in a tapered shape having a small diameter on the circuit pattern substrate 2 side and a large diameter sequentially toward the surface side of the insulating layer 4. The convex portions formed on the mold are tapered so that the tip side is gradually reduced in diameter, and the lands 2b of the circuit pattern substrate 2 are sandwiched from the top and bottom at the tips of the respective convex portions. By injecting the molten resin into the mold, the electronic component 3 mounted in advance on the circuit pattern substrate 2 is sealed with the insulating resin layer 4, and on the upper and lower surfaces of the land 2b on which the post-attached electronic component 5 is mounted, As shown in FIG. 3, tapered recesses 4a and 4b are formed.

On the other hand, a recess (first recess) 4a formed on the insulating resin layer 4 side that covers the upper surface of the circuit pattern substrate 2 (the mounting surface of the post-attached electronic component ) 4a has a lead 5a of the post-attached electronic component 5 in the through hole 2c of the land 2b. It is formed as follows for easy insertion.

  That is, the tip of the lead 5a is sharply cut in advance so that the lead 5a of the electronic component 5 can be easily inserted into the through hole 2c of the land 2b, and the cutting method is also one side of the tip of the lead 5a. There is a single-edged cut in which only the tip is cut, and a double-edged cut in which both sides of the tip of the lead 5a are cut.

  The thickness of the circuit pattern substrate 2 made of a thin metal plate is normally about 1.2 to 1.6 mm, but in the embodiment, a thickness of 0.8 mm is used.

  The concave portion 4a provided on the upper side of the land 2b is used as a guide when the lead 5a of the post-attached electronic component 5 is inserted into the through hole 2c of the land 2b. However, if the diameter on the small diameter side of the concave portion 4a is large, the through hole 2c A large shelf-like portion 4c is generated around the rim, which becomes an obstacle when the lead 5a is inserted into the through hole 2c.

  If the diameter on the small diameter side of the concave portion 4a is reduced, the shelf-like portion 4c can be reduced, but if it is too small, if there is a positional deviation (usually about 0.1 to 0.2 mm) between the mold and the circuit pattern substrate 2, The through holes 2c are covered with the insulating resin layer 4 and it becomes difficult to insert the leads 5a.

  As described above, the lead 5a of the retrofitted electronic component 5 is sharply cut at the tip in advance, so that the width of the shelf-like portion 4c formed around the through hole 2c is about 1/2 of the diameter of the lead 5a. Even though the tip of the lead 5a guided by the recess 4a is not blocked by the shelf 4c, the through hole 2c is insulated even if a misalignment occurs between the mold and the circuit pattern substrate 2. Since it is not covered by the resin layer 4, the width of the shelf-like portion 4c is set to 1/2 or less of the diameter of the lead 5a.

  As a result, the diameter of the recess 4a on the small diameter side is approximately twice the diameter of the lead 5a.

  Further, the taper inclination angle θ1 of the concave portion 4a is set to about 5 degrees with respect to the perpendicular, and the following effects are also obtained.

  As described above, the thickness of the circuit pattern board 2 is usually about 1.2 to 1.6 mm. Therefore, the lead 5a of the post-installed electronic component 5 is inserted into the through hole 2c and the post-installed electronic component 5 is mounted. At this time, the post-attached electronic component 5 can be self-supported depending on the thickness of the circuit pattern substrate 2, but when the plate thickness of the circuit pattern substrate 2 is about 0.8 mm as in the embodiment, the post-attached electronic component 5 is self-supporting. The state becomes unstable.

  However, the diameter of the concave portion 4a provided on the upper side of the land 2b is approximately twice the diameter of the lead 5a and the inclination angle θ1 is about 5 degrees, so that the thickness of the circuit pattern substrate 2 is reduced. In addition, the retrofitted electronic component 5 can be made independent in a stable state.

On the other hand, when the diameter of the concave portion (second concave portion) 4b provided on the solder surface of the land 2b is reduced, the solder jet 6 blown up in the flow soldering process does not reach the through hole 2c, causing a solder failure.

  In order to prevent this, the diameter of the concave portion 4b on the small diameter side is approximately the same as that of the conventional one, and the taper inclination angle θ2 is approximately 45 degrees with respect to the perpendicular.

  As a result, the solder jet 6 blown up in the flow soldering process sufficiently reaches the through-hole 2c as shown in FIG. 9, so that solder failure can be prevented.

  Further, when the through holes 2c provided in the adjacent lands 2b are close to each other, when the inclination angle θ2 of the recess 4b is set to 45 degrees, the adjacent recesses 4b are continuous as shown in FIG. By forming the thin weir 4d and the partition rib 4e between the through holes 2c, the solder does not cross between the adjacent through holes 2c, so that the through holes 2c are prevented from being short-circuited by the solder. Will be able to.

Even if the thin weir 4d is formed of a rib, the same effect can be obtained.

  On the other hand, the tie bar 2a for temporarily connecting the circuit patterns to each other so that adjacent circuit patterns on the circuit pattern substrate 2 are not separated is formed by punching the periphery of the tie bar 2a into a square hole after forming the resin-sealed substrate. Although it cut | disconnects conventionally, since the solder jet flow blows to the upper surface side of the resin sealing board | substrate from the punched square hole, the blow-up height of the solder jet flow could not be made so high.

  Therefore, in the embodiment, as shown in FIGS. 5 and 6, when the rectangular recess 4f elongated in the longitudinal direction of the tie bar 2a is formed so as to surround the tie bar 2a, the thin portion of the insulating resin layer 4 is formed in the recess 4f. 4 g is formed so as to sandwich the tie bar 2a.

  Conventionally, the entire concave portion 4f is punched to cut the tie bar 2a. However, the punching hole 2d can be made small by punching the punching hole 2d while leaving the thin portion 4g. The jet 6 can be prevented from blowing up from the punched hole 2d to the upper surface side of the resin sealing plate.

  Next, the operation of the thus configured resin sealing substrate will be described.

  When mounting the retrofitted electronic component 5 on the main body 1 of the resin-encapsulated substrate in which the insulating resin layers 4 are formed on both surfaces of the circuit pattern substrate 2 made of a thin metal plate, a component mounting apparatus (mounter) is used automatically. There are a method of mounting the retrofit component 5 and a method of manual mounting by the operator. In either case, the postmount electronic component 5 is inserted into the through hole 2c formed in the land 2b at a predetermined position from the upper surface side of the main body 1. The lead 5a is inserted as shown in FIG.

  At this time, since the tapered recess 4a guides the tip of the lead 5a to the through hole 2c, the insertion into the through hole 2c can be smoothly performed in a short time. However, when the insulating resin layer 4 is formed, the circuit pattern substrate 2 is formed. Since the diameter of the small diameter side of the recess 4a is made larger than the diameter of the through hole 2c in advance so that the through hole 2c is not covered with the insulating resin layer 4 even if there is a misalignment, the shelf-like portion 4c around the through hole 2c. Has occurred.

  However, since the width of the shelf-like portion 4c is set in advance to be equal to or less than 1/2 of the diameter of the lead 5a, even if the tip of the lead 5a hits the shelf-like portion 4c as shown in FIG. Since almost half of the diameter is in the through hole 2c, the tip of the lead 5a can be easily inserted into the through hole 2c as shown in FIG. 8 only by slightly shifting the position of the lead 5a.

  Further, since the tip of the lead 5a of the post-installed electronic component 5 mounted on the main body 1 is sharpened by single-edged cutting or double-edged cutting as indicated by a virtual line in FIG. Since it hardly hits the shelf 4c, it can be smoothly inserted into the through hole 2c.

  As a result, in the case of automatic mounting using a mounter, there is no problem that the tip of the lead 5a is deformed and cannot be mounted, and the lead 5a of the retrofitted electronic component 5 can be mounted in a short time even when mounting manually. Can be inserted into the through hole 2c, so that the mounting operation can be performed efficiently.

  On the other hand, the resin-sealed substrate on which the mounting of the retrofitted electronic component 5 is completed is sent to the flow soldering process and used for flow soldering, but the recess 4b of the insulating resin layer 4 formed on the solder surface side of the resin-sealed substrate. Is formed by a taper having an inclination angle θ2 of approximately 45 degrees, the solder jet 6 blown toward the lower surface of the resin-encapsulated substrate 4 is sufficiently passed through the recess 4b into the through hole 2c as shown in FIG. To reach.

  As a result, solder defects such as the lead 5a inserted into the through hole 2c not being soldered to the land 2b hardly occur.

  Moreover, since the punching hole 2d punched to cut the tie bar 2a is also sufficiently smaller than the conventional one, the solder jet 6 does not blow up from the punching hole 2d to the upper surface side of the resin-sealed substrate. The height of the solder jet 6 can be increased, and the reliability of flow soldering can be improved.

  Since the resin-encapsulated substrate of the present invention can be inserted into the through hole without mounting the lead tip of the post-attached electronic component against the shelf-like portion around the through-hole when mounting the post-attached electronic component, the resin-sealed substrate is made of a thin metal plate. It is most suitable for a resin-sealed substrate in which electronic components mounted on a circuit pattern substrate are sealed with an insulating resin layer.

The perspective view from the upper part of the resin sealing substrate which becomes embodiment of this invention. The top view of the lower surface side of the resin sealing substrate which becomes embodiment of this invention. The expanded sectional view which follows the AA line of FIG. The expanded sectional view which follows the BB line of FIG. FIG. 3 is an enlarged plan view in a circle C in FIG. 2. Sectional drawing which follows the DD line | wire of FIG. Action | operation explanatory drawing of the resin sealing board | substrate which becomes embodiment of this invention. Action | operation explanatory drawing of the resin sealing board | substrate which becomes embodiment of this invention. Action | operation explanatory drawing of the resin sealing board | substrate which becomes embodiment of this invention. Explanatory drawing of the conventional resin sealing board | substrate. Explanatory drawing of the conventional resin sealing board | substrate. Explanatory drawing of the conventional resin sealing board | substrate.

Explanation of symbols

2 Circuit pattern board 2a Tie bar 2b Land 2c Through hole 3 Electronic component 4 Insulating resin layer 4a Concave 4b Concave 4c Shelf 4f Concave 4g Thin part 5 Retrofitted electronic component 5a Lead 6 Solder jet

Claims (3)

A circuit pattern board in which a circuit pattern is formed by punching a thin metal plate, a land having a through hole for mounting an electronic component, and the like, and the circuit pattern board by covering the front and back surfaces of the circuit pattern board consisting of an insulating resin layer which seals the mounted electronic components to a resin sealing substrate, the circuit pattern board the front and rear surfaces the insulating resin layer provided on the side to be retrofit electronic component mounting surface out of the And a tapered first recess having a large diameter on the surface side and sequentially decreasing in diameter toward the through hole side for mounting the post-installed electronic component, and by providing the first recess around the through hole. and a formed ledge, to set the diameter of the small-diameter portion of the first recess such that half or less of the diameter of the ledge width of the retrofit electronic component leads With inclination angle of the inner circumferential surface of the tapered first recess is set to approximately 5 degrees,
Further, the insulating resin layer provided on the solder surface side of the front and back surfaces of the circuit pattern substrate has a taper that has a large diameter on the front surface side and gradually decreases in diameter toward the through hole side on which the post-installed electronic component is mounted. A resin-encapsulated substrate characterized in that a second recess having an inner peripheral surface and an inclination angle of approximately 45 degrees is formed . In the time of mounting a plurality of the post with the electronic components on the circuit pattern, in the case where the through hole with each other for mounting the lead of each post with the electronic components are close were formed corresponding to the respective through hole the The resin-encapsulated substrate according to claim 1 , wherein the second concave portion is formed so as to be continuous with each other, and a thin-walled portion or a rib is formed between the through holes adjacent to each other . In the insulating resin layer before Symbol circuit pattern covers the tie bars provided so as not to separate to form a rectangular recess to expose the tie bar, and forming a thin portion reaching said tie bar to said rectangular recess The resin-sealed substrate according to claim 1, wherein the tie bar is punched and cut while leaving the thin portion.

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