JP2646331B2 - Lead pin carrier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pin carrier for mounting I / O lead pins on a substrate on which an IC chip is mounted.

[0002]

2. Description of the Related Art A PGA (Pin Grid Array) type electronic component is manufactured by mounting a plurality of I / O lead pins on a substrate on which an IC chip is mounted. Such an electronic component is detachably mounted on a socket having a plurality of contacts connected to an external circuit. Then, each lead pin is received by each contact or the like, contacts each other, and is connected to an external circuit via each contact.

Conventionally, as a method of mounting such lead pins on a substrate, a method has been adopted in which a through hole is formed in the substrate, and the lead pin is press-fitted into the through hole. In some cases, a method of soldering a head portion of a lead pin to a land provided on a lower surface of a substrate is employed.

[0004]

However, in the former method, it is necessary to form a through hole in a space for mounting electronic components and laying wiring, so that the mounting density of the substrate is accordingly reduced. There is a problem that it becomes low. On the other hand, in the latter method, the placement accuracy of each lead pin cannot be ensured because the pad and the head are soldered in a displaced state, or the strength of mounting the lead pin to the substrate is insufficient with the above soldering alone. Problem.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and it is possible to increase the mounting density of a board, improve the arrangement accuracy of lead pins, and sufficiently secure the mounting strength of lead pins. It is an object of the present invention to provide such a lead pin carrier.

[0006]

In order to achieve the above object, a lead pin carrier according to the present invention comprises a carrier member formed in a plate shape and having a plurality of press-fit holes formed in a thickness direction and aligned therewith; A plurality of lead pins which are press-fitted into the press-fitting holes and held by the carrier member. Then, with respect to the substrate on which the electronic components are mounted on the upper surface, the carrier member holding the plurality of lead pins is positioned so that the head portion of each lead pin and each land formed on the lower surface of the substrate face each other, and each head portion And the respective lands are soldered to integrally fix the carrier member and the plurality of lead pins to the substrate.

[0007] The carrier member may be provided with a projection which is inserted into a recess formed in the substrate and performs the above-mentioned positioning.

[0008]

In such a lead pin carrier, a plurality of lead pins are press-fitted into press-fit holes formed in alignment with the carrier member, whereby the lead pins are accurately aligned and held so as to correspond to the arrangement of the lands on the lower surface of the substrate. The plurality of lead pins are firmly held by the carrier member integrally fixed to the substrate, so that the mounting strength of the lead pins to the substrate is increased. Since there is no need to provide through holes for press-fitting lead pins in the substrate, the upper surface of the substrate can be effectively used for mounting electronic components or laying wiring.

[0009]

Preferred embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a lead pin carrier 1 according to the present invention. The lead pin carrier 1 is composed of a carrier member 2 formed in a rectangular plate shape from a resin, and a plurality of I / O lead pins 3, 3,... Formed in a pin shape from a conductive material.

A plurality of press-fit holes 2b, 2b,... Penetrating in the thickness direction are formed in the center plane portion 2a of the carrier member 2 so as to be aligned in the front-rear and left-right directions. The direction of arrow F shown in FIG. 1 is defined as “front” of the carrier member 2 and the direction of arrow L is defined as “left”. Further, standoff portions 2c, 2c, which are higher than the upper surface of the central flat portion 2a, are formed at both left and right ends of the carrier member 2 so as to extend in the front-rear direction. The upper surfaces of the standoff portions 2c, 2c extend in parallel with the central flat portion 2a. Further, a cylindrical guide protrusion 2d protruding upward is provided near the left front corner and the right rear corner of the center plane portion 2a of the carrier member 2, that is, on one diagonal line of the center plane portion 2a. , 2d are formed. In addition, the height of these guide protrusions 2d, 2d is higher than the stand-off part 2c.

Each of the lead pins 3 has a main body 3a having a small outer diameter and extending vertically, a head 3b formed by increasing the diameter of the upper end of the main body 3a, and a main body 3a.
The upper part a of FIG. 3a is formed by projecting portions 3c, 3c formed by slightly projecting the both side surfaces. The main body 3a
Has an outer diameter substantially equal to the inner diameter of the press-fit hole 2b of the carrier member 2, and the outer width between the overhang portions 3c, 3c is larger than the inner diameter of the press-fit hole 2b.

The lead pin 3 thus formed is inserted into the press-fit hole 2b of the carrier member 2 from the lower end of the main body 3a. Then, the lead pins 3 are pressed into the carrier member 2 and held by being pushed into the press-fit holes 2b. It is desirable that the height of the upper surface of the head portion 3b of each lead pin 3 held by the carrier member 2 be slightly lower than the height of the upper surface of the stand-off portion 2c of the carrier member 2, as shown in FIG. .

As shown in FIG. 3, the lead pin carrier 1 assembled in this manner is mounted on the lower surface 5b of the substrate 5 on which the electronic components C and the like are mounted on the upper surface 5a.
A plurality of disc-shaped lands (terminals) 6, 6,... Are attached to the lower surface 5b of the substrate 5. The arrangement of these lands 6, 6,... Corresponds to the arrangement of the plurality of lead pins 3, 3,. A solder paste 7 is applied to the lower surface of each land 6 by printing or the like.

A plurality of lands 6 on the substrate 5
On the left and right outer sides of the portion provided with 6,... Are formed two positioning holes 8, 8 which are opened on the lower surface 5a (however, only the left positioning hole 8 is shown in FIG. 3). In addition, both positioning holes 8 are provided in the carrier member 2.
Are arranged corresponding to the arrangement of the two guide projections 2d, 2d.

The lead pin carrier 1 is mounted on such a substrate 5.
4 is inserted, the upper end of the guide projection 2d of the carrier member 2 is inserted into the positioning hole 8 of the substrate 5, as shown in FIG. Thereby, the substrate 5 of the lead pin carrier 1 is
Is positioned in the horizontal direction with respect to
Head portion 3b and each land 6 accurately face each other.

Further, the guide projection 2d is inserted deep into the positioning hole 8, and the upper surface of the stand-off portion 2c is brought into contact with the lower surface 5b of the substrate 5. As a result, the vertical positioning of the lead pin carrier 1 with respect to the substrate 5 is performed, and the head portion 3b of each lead pin 3 comes into contact with or comes close to each land 6 while being embedded in the solder paste 7.

With the lead pin carrier 1 thus positioned with respect to the substrate 5, the substrate 5 is put into a heating furnace (not shown) to reflow the solder paste 7, and the head 3b of each lead pin 3 and each The land 6 is joined. Thus, the carrier member 2 is fixed to the substrate 5 integrally with each lead pin 3.

The substrate 5, to which the lead pins 3, 3,... Are attached, is mounted on a socket 9 in which a plurality of contacts 9a, 9a,. Each lead pin 3 is inserted into each contact 9a.
Since the arrangement accuracy of the lead pins 3 is ensured, each lead pin 3 can be smoothly inserted into each contact 9a. Then, the lead pin 3 received by the contact 9a
Is connected to an external circuit (I not shown) through each contact 9a.
C tester). Also, the carrier member 2
Is to hold each lead pin 3 firmly,
Since the connection between the substrate 5 and the land 6 is reinforced, there is no fear that the lead pins 3 come off when the substrate 5 is detached from the socket 9.

In the above embodiment, a method is adopted in which the solder paste 7 is applied to the land 6 in advance, and the lead pin carrier 1 is positioned and then reflowed. However, the following method is used instead. Is also good. In FIG.
The pallet 40 formed in a plate shape is shown. A plurality of circular concave portions 41 are formed on the upper surface of the pallet 40. The arrangement of the recesses 41, 41,... Corresponds to the arrangement of the lead pins 30 pressed and held in the carrier member 20, as shown in FIG. In each recess 41, FIG.
As shown in FIG. 7, a ring solder 70 formed in an annular shape is inserted and arranged. The outer diameter of the ring solder 32 is slightly smaller than the inner diameter of the recess 31, and the inner diameter of the ring solder 32 is equal to or slightly smaller than the outer diameter of the head portion 30b of the lead pin 30.

Then, as shown in FIG.
No. 0 head part 30b is pressed into the inside of the ring solder 70 held on the pallet 40. Thereby, as shown in FIG. 8, the lead pin carrier 10 in which the ring solder 70 is attached to the outer periphery of the head section 30 is assembled.

The carrier member 20 shown in FIGS. 7 and 8 is formed thinner than the carrier member 2 of the above embodiment. As shown in detail in FIG. 8, the carrier member 20 includes a plurality of press-in holes 20b, 20b,.
It has a stand-off portion 20c and a guide protrusion 20d. The lead pin 30 is different from the lead pin 30 of the above-described embodiment, and initially includes a main body 30a that extends straight up and down, and a head 30b formed by increasing the diameter of the upper end of the main body 30a. . The outer diameter of the main body 30a of the lead pin 30 is equal to or slightly larger than the inner diameter of the press-fit hole 20b of the carrier member 20.

Then, the main body 30a of the lead pin 30 is press-fitted into the press-fitting hole 20b of the carrier member 20, and the head 3
In a state where the lower surface of Ob is in contact with the upper surface 20a of the carrier member 20, the upper portion of the main body 30a is crushed to form the caulked portion 30c. As a result, the lead pin 30 does not come off the carrier member 20 and is held by the carrier member 20. After holding the lead pin 30 on the carrier member 20 in this manner, the head 30b of the ring solder 70 described above is used.
Attach to.

In the lead pin carrier with ring solder 10 assembled as described above, the guide projection 20d of the carrier member 20 is inserted into the positioning hole 80 formed on the lower surface 50b side of the substrate 50, as shown in FIG. The upper surface of the stand-off portion 20c is positioned with respect to the substrate 50 by making contact with the lower surface 50b of the substrate 50. As a result, the head portion 30b of each lead pin 30 is connected to each land 60.
Is exactly the same as the carrier member 2 in the above embodiment. Then, in this state, the ring solder 70 is heated in the heating furnace to reflow (7).
0 ′), the head portion 30b of the lead pin 30 and the land 60 provided on the lower surface 50a of the substrate 50 are soldered. The carrier member 20 fixed to the substrate 50 integrally with the lead pins 30 in this manner
Increasing the mounting strength with respect to 0 is the same as in the carrier member 2 of the above embodiment.

[0024]

As described above, the lead pin carrier of the present invention has a plurality of lead pins aligned and held by a carrier member, and the head of each lead pin is positioned so as to accurately face a land formed on the substrate. Then, the head portion and the land are joined by soldering. Therefore, by using the present lead pin carrier, the arrangement accuracy of the plurality of lead pins attached to the substrate can be ensured.
Further, in this lead pin carrier, the carrier member is fixed to the substrate integrally with the lead pin while holding the lead pin. For this reason, the carrier member can firmly support the lead pin after being attached to the land. Therefore, if this lead pin carrier is used,
The mounting strength of the lead pins to the substrate can be increased. Since there is no need to provide a through hole for press-fitting lead pins into the board as in the related art, the mounting density of the board can be further increased.

[Brief description of the drawings]

FIG. 1 is a perspective view of a lead pin carrier according to the present invention.

FIG. 2 is a cross-sectional view of the lead pin carrier.

FIG. 3 is a sectional view of a substrate on which the lead pin carrier is mounted.

FIG. 4 is a sectional view showing a state where the lead pin carrier is mounted on the substrate.

FIG. 5 is a cross-sectional view showing a state in which the board is attached to a socket.

FIG. 6 is a perspective view of a pallet used in a second embodiment of the lead pin carrier according to the present invention.

FIG. 7 shows a second example of the pallet and the lead pin carrier.
It is sectional drawing which shows an Example.

FIG. 8 is a sectional view showing a second embodiment of the lead pin carrier.

FIG. 9 is a cross-sectional view showing a state in which the lead pin carrier is mounted on a substrate according to a second embodiment.

[Explanation of symbols]

 1, 10 Lead pin carrier 2, 20 Carrier member 2b, 20b Press-fit hole 2c, 20c Stand-off portion 2d, 20d Guide protrusion 3, 30 Lead pin 3b, 30b Head portion 5, 50 Substrate 6, 60 Land 7 Solder paste 70 Ring solder 8 , 80 Positioning hole 9 Socket 40 Pallet C Electronic component

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroshi Kanzaki 510 Minamikoji, Futako-ku, Takatsu-ku, Kawasaki-shi, Kanagawa Prefecture No. 3 Inoue Building Inside August (72) Inventor Hideki Tashiro Futatsuji, Takatsu-ku, Kawasaki-shi, Kanagawa 510 Minami Kochi No. 3 Inoue Building In August

Claims (2)

(57) [Claims] 1. A carrier member which is formed in a plate shape and in which a plurality of press-fit holes penetrating in a thickness direction are arranged and formed; and a plurality of lead pins which are press-fitted into the press-fit holes and held by the carrier member. The carrier member holding the plurality of lead pins is positioned with respect to the substrate on which the electronic component is mounted on the upper surface such that the head portion of each of the lead pins and each land formed on the lower surface of the substrate face each other. A lead pin carrier, wherein the head member and the lands are joined by soldering so that the carrier member and the plurality of lead pins are integrally fixed to the substrate. 2. The lead pin carrier according to claim 1, wherein said carrier member is provided with a projection which is inserted into a recess formed in said substrate to perform said positioning.