JP2532421Y2 - Resin molding equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molding apparatus.

[0002]

2. Description of the Related Art Conventionally, as a semiconductor device having a heat sink such as a power transistor, as shown in FIG. 3, a heat sink 102 having a lead 101 formed on a lead frame 100 via a tie bar 107 is used. A semiconductor pellet 103 is mounted on the substrate, and electrodes on the surface of the semiconductor pellet (not shown) and leads 104 disposed on both sides of the heat sink 102 are wire-bonded with fine metal wires 105, respectively. Some are coated with. As a resin molding device used for manufacturing such a semiconductor device, for example, as shown in a sectional view in FIG. 4, the respective leads 101 and 104 of the lead frame 100 are clamped and fixed by upper and lower dies 1 and 2. A cavity 3 into which resin is injected is formed on the abutting surface, and molten resin is injected into the cavity 3 from a gate through an external pot (not shown) through a runner.

[0003] In such a resin molding apparatus, for example, each lead 101 of the lower mold 2 is prevented so that the resin leaked from the cavity 3 is buried between the leads 101 and 104 and cannot be removed after the resin is cured. , 104 and the tie bar 107.
The blocks 4 are protruded by the thickness of 01..., So that the resin does not leak between the leads 101 and 104 and accumulate due to the blocks 4.

[0004]

However, when looking at the processing accuracy of the lead frame 100 to be resin-molded, minute variations are likely to occur in the widths and the like of the respective leads 101 and 104, and the lead frame 100 is attached to the upper and lower molds 1. , 2, each lead 101, 1
There is a problem that the respective blocks 4 of the lower mold 2 do not fit between the blocks 04. As described above, when the lead frame 100 having a variation in processing accuracy is sandwiched between the upper and lower molds 1 and 2,
Each lead 101, 104 is pinched and deformed while riding on the block 11, and in the worst case, the upper and lower molds 1, 2,
There was a problem such as scratching.

[0005]

In order to solve the above-mentioned problems, a resin molding apparatus according to the present invention includes a lead frame in which a number of leads are formed in upper and lower molds having cavities formed in an abutting surface. In a resin molding apparatus for covering a position with a resin, at least a resin stopper block having a tapered tapered surface is disposed on a lower mold of a cavity peripheral wall between each lead of the lead frame so as to be vertically movable.

[0006]

In the resin molding apparatus having the above structure, when the lead frame is sandwiched and fixed between the upper and lower dies, the distance between the leads fluctuates due to the vertical movement of the resin stopper block having a tapered tapered surface disposed between the leads. Will be able to do that. Therefore, even if a processing error occurs in the width of each lead formed on the lead frame, the vertical movement of the resin stopper block absorbs the processing error by the tapered surface, so that the resin stopper can be reliably disposed. Accordingly, there is no need to worry about deformation of each lead of the lead frame or damage to the upper and lower molds, and it is possible to perform resin molding only at a desired position without filling the resin between the leads.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view of a resin molding apparatus according to an embodiment of the present invention, and FIG.
FIG. 3 is a schematic cross-sectional view along a line. The resin molding apparatus shown in the figure is substantially the same as the conventional apparatus shown in FIG. 4 except that a resin stopper block 10 is formed and arranged on the peripheral wall 3a of the cavity 3, so the same members are given the same reference numerals. The description is omitted here.

The above resin stopper block 10 comprises upper and lower molds 1,
2 each lead 10 of the lead frame 100 sandwiched between
The lower end of the resin stopper block 10 is attached to a bolt 11 screwed to a support 21 of the lower mold 2, for example. It is attached and is vertically movable with respect to the support base 21 by the rotation of the bolt 11. The spacer 12 is appropriately attached between the support 21 and the lower end of the resin stopper block 10 during resin molding. In addition, resin stopper block 1
The leading end of the taper 0 has tapered surfaces 13, 13 whose both end faces parallel to the leads 101, 104 become thinner toward the leading end. The length can be changed by adjusting the length of the projection upward from the top. That is, lead frame 1
When there is no processing error in each of the leads 101 and 104, the resin stopper block 10 may be protruded as shown in FIG. 2, and when the lead is processed to be wide, the protruding length is suppressed. Thereby, the interval between the resin stopper blocks 10, 10 is widened by the tapered surfaces 13, 13, so that the leads 101, 104 can be reliably arranged.

The resin molding apparatus having the above structure is used, for example, for resin coating of a semiconductor device having a radiator plate such as a power transistor. As shown in FIG. After the semiconductor pellets 103 mounted on the heat sink 102 are sandwiched and fixed by the respective leads 101 and 104 of the frame 100 and positioned in the cavity 3 formed on the abutment surface, an external view is provided in the cavity 3. The molten resin supplied from a pot (not shown) through a runner is injected through a gate. At this time, the lead frame 100 is
Hold each resin stopper block 10 between the bolts 1
When the lead 101 is moved up and down by the rotation of the block 1, as shown in FIG.
It can be in a state of being sandwiched between the 0, 10 tapered surfaces 13, 13 exactly. Therefore, each lead 101, 1
Even if a processing error or the like occurs in the width or the like of the resin block 04, the protrusion length of the resin stopper blocks 10 and 10 from the lower mold 2 is simply changed as necessary with the bolt 11, and the processing is performed by the tapered surfaces 13 and 13 at the tips. Errors can be absorbed, and the leads 101 and 104 can be deformed,
The lead frame 100 can be pinched and fixed without damaging the lead frame 100. The inclination angle of the tapered surface 13 formed at the tip of each resin stopper block 10 is about 3 to 5 degrees. If the resin stopper block 10 can also move up and down by about 0.1 mm, the processing accuracy of the lead frame 100 can be reduced. Variations can be sufficiently absorbed.

Then, the lead frame 100 is placed in a state where the leads 101 and 104 are arranged between the resin stopper blocks 10.
When resin is injected by sandwiching and fixing between the upper and lower molds 1 and 2,
The resin enters between the leads 101 and 104 and the tapered surface 13 of the resin stopper block 10. However, when the resin is cured, the resin is in a tapered state. Can be
There is no possibility that the resin is buried in the root between the leads 101 and 104 and cannot be removed.

[0012]

As is clear from the above description, in the resin molding apparatus of the present invention, even if a processing error occurs in the width of each lead formed on the lead frame, the resin stopper block is tapered by the vertical movement. The processing error of each lead can be absorbed by the surface. Therefore, when the lead frame is sandwiched between the upper and lower molds, the leads are not deformed or the upper and lower molds themselves are not damaged, and there is no fear that the resin remains between the leads after resin molding and cannot be removed. Play.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a resin molding apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the resin molding apparatus of the present invention, taken along line AA of FIG. 1;

FIG. 3 is a schematic sectional view showing an example of a resin molded product.

FIG. 4 is a schematic sectional view of a conventional resin molding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper mold 2 Lower mold 3 Cavity 3a Peripheral wall 10 Resin stopper block 13 Tapered surface 100 Lead frame 101,104 Lead

Claims (1)

(57) [Scope of request for utility model registration] 1. A resin molding apparatus for sandwiching and fixing a lead frame in which a number of leads are formed in upper and lower molds having a cavity formed in an abutting surface and covering a predetermined position with a resin, at least between each lead of the lead frame. A resin stopper block having a tapered tapered surface is vertically movably arranged in a lower mold of the cavity peripheral wall of the resin molding apparatus.