JPH09309127A - Molding device for resin sealing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make easy the fixing work for a rest of a mold and eliminate as much as possible the deviation of the position following the mold clamping and mold opening of top and bottom forces by retaining one of the top and bottom forces in the state of pressing one to the rest and fixing the other on the. SOLUTION: An air pressure cylinder is provided with its movable shaft end fixed on a retaining component on the upper face of an upper rest 1. In the case of manufacturing by using a molding device, a cylinder is stretchingly moved and retained in the state of pressing a top force 4 to the lower face of the upper rest 1. The top force 4, therefore, is not fixed on the upper rest 1 completely, and can be moved slightly in the lateral direction along the lower face of the upper rest 1. At that time, an engaging body is moved into a channel section formed preliminarily on the upper rest 1. A bottom force 5 is fixed on a lower rest 2 in the state of being positioned to correspond to the top force 4. Columnar positioning pins and positioning holes for positioning upper and lower rest 4 and 5 are provided for registering the rests.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a device for molding a resin sealing portion of an electronic component such as.

[0002]

2. Description of the Related Art Generally, electronic parts such as ICs and TRs are manufactured through a process of sealing an electronic element bonded on a lead frame made of iron or the like with a resin sealing portion such as an epoxy resin. You. Then, conventionally, the following apparatus has been used for molding the resin sealing portion.

FIG. 5 is a side view showing a conventional molding apparatus for resin sealing. This molding apparatus has a pair of upper and lower molds 31 and 32 made of hard alloy or the like. These upper and lower molds 31,
The numeral 32 is fixed to the upper and lower pedestals 34 and 35 of the press body 33, respectively, and the lower die 32 is movable up and down with respect to the upper die 31 in a stationary state by driving a hydraulic cylinder or the like (not shown). . Further, in the lower mount 35, the upper and lower molds 3
Heater block (not shown) for heating 1, 32
Has been fixed. A cavity (not shown) is formed on each of the mating surfaces of the upper and lower molds 31 and 32 to cover the electronic element on the elongated lead frame.

The lower die 32 is provided with a plurality of positioning pins (not shown). One of these positioning pins is for positioning with the upper die 31 and is used when fixing the upper and lower dies 31, 32 to the upper and lower pedestals 34, 35 in a state of being positioned (note that the upper die is The mold 31 is provided with a positioning hole (not shown) that fits with the positioning pin). The other one of the positioning pins is for positioning with the lead frame 36,
The fitting with a positioning hole (not shown) formed in the lead frame 36 serves to perform positioning with the lead frame 36.

Then, in the molding of the resin sealing portion, the lead frame 36 is transferred between the upper and lower molds 31, 32 and the lower mold 32.
The upper and lower molds 3 are placed in a state of being positioned above, sandwiched by clamping the upper and lower molds 31 and 32, and the molten resin is injected into the cavity to cover the electronic element, and then the upper and lower molds 3
It is carried out by a method of discharging from between the upper and lower molds 31, 32 by opening the molds 1, 32.

[0006]

In the above molding apparatus,
Since the upper and lower dies 31 and 32 are fixed to the upper and lower pedestals 34 and 35 while aligning them, this fixing work is very troublesome. Further, in the above-described molding apparatus, each time the upper and lower molds 31, 32 are repeatedly clamped and opened, the impact force at that time causes fine movements on the upper and lower mounts 34, 35, respectively. Is likely to be displaced. If the mold is clamped in this misaligned state,
There is a problem that the positioning members on the upper and lower molds 31 and 32 are likely to be significantly worn, the lead frame 36 is displaced on the lower mold 32, and the resin sealing portion covering the electronic element is easily deformed. is there.

Further, conventionally, it is necessary to use cemented carbide as the material of the positioning member which is easily worn as described above, and the material cost thereof increases. In addition, since the positioning member that is worn as described above needs to be replaced with a new positioning member that is not worn, the cost required for the positioning member increases, and the more frequent the replacement work, the easier the workability is. Becomes very bad.

The present invention has been made in view of such circumstances, and it is easy to fix the mold to the pedestal, and furthermore, the positional deviation due to the opening of the upper and lower molds from the mold clamping mold is eliminated as much as possible. An object of the present invention is to provide a molding device for resin encapsulation of an electronic component to be obtained.

[0009]

In order to achieve the above object, the present invention provides a press main body having upper and lower mounts that can move toward and away from each other, and a press main body provided on each of the facing surfaces of the upper and lower mounts. Upper and lower molds, and positioning means for aligning the upper and lower molds are provided on the mating surfaces of the upper and lower molds, and the resin sealing portion that covers the electronic element with the mating surfaces of the upper and lower molds. Wherein one of the upper and lower molds is held in a pressed state against the gantry, and the other of the upper and lower dies is fixed to the gantry. The present invention provides a molding device for resin sealing of electronic components.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited thereto. FIG. 1 is a schematic view showing a molding device for resin sealing. This molding apparatus for resin encapsulation has a press body 3 having a fixed upper base 1 made of a hard alloy and a lower base 2 made of a hard alloy that can freely move toward and away from the upper base 1, The upper and lower pedestals 1 and 2 are provided with an upper mold 4 and a lower mold 5 made of a hard alloy, which are attached to opposite surfaces of the upper and lower cradle 1, respectively. A heater block (not shown) is built in the upper mount 1 and the lower mount 2.

FIG. 2 is a partially cutaway side view showing the details of the mounting structure of the upper die 4 on the upper frame 1. Upper stand 1
Two through holes 6 (only one of which is shown in cross section) are formed in the through hole 6, and the slide shafts 7 are inserted into the through holes 6 (in the through hole 6, respectively). A ball bush is arranged so that the slide shaft 7 can move up and down). These slide shafts 7 are connected to a plate-shaped holding member 8 (at a position on the upper frame 1). A disk-shaped body 9 having a diameter larger than this diameter is fixed to the lower end surface of the slide shaft 7. A locking body 10 for locking the disc-shaped body 9 is fixed to the upper surface of the upper mold 4. As shown in FIG. 3, the locking body 10 is formed with a cutout portion 10a into which the disc-shaped body 9 is inserted. These locks are performed by sliding the upper die 4 in the lateral direction (the direction of the arrow in the drawing) so that the disk-shaped body 9 is inserted into the cutout portion 10a.

In addition, the upper mount 1 (as shown in FIG. 2 again)
A pneumatic cylinder 11 is arranged on the upper surface of the cylinder with the holding member 8 fixed to the movable shaft end thereof. And
When manufacturing using this molding apparatus, the cylinder 11 is extended and the upper die 4 is held in a pressed state against the lower surface of the upper frame 1. Therefore, the upper mold 4 is not completely fixed to the upper mount 1, but can be finely moved laterally along the lower surface of the upper mount 1. At this time, the locking body 10
It will enter into the groove portion previously provided in the upper mount 1.

Further, when the type of electronic parts to be manufactured changes and it becomes necessary to replace the upper mold 4, the cylinder 11 is contracted to release the pressed state, and the above-mentioned FIG.
As shown in FIG. 5, the upper mold 4 is slid in the direction opposite to the direction of the arrow in the figure and removed from the slide shaft 7. Further, as shown in FIG. 2 again, since the compression spring 13 is attached to the slide shaft 7 at a portion between the holding member 8 and the upper frame 1, the cylinder 11 can be moved as described above.
When is contracted, most of the weight of the upper mold 4 is not added to the cylinder 11 and is relieved by the compression force of the compression spring 13.

In addition, a side guide 14 is fixed to the lower surface of the upper mount 1 so as to surround the peripheral portion of the upper mold 4.
It serves to correct the lateral slide of the upper die 4 (more than necessary). Side of upper mold 4 and side guide 14
The clearance between and is about 0.2 to 0.3 mm.
Further, the lower mold 5 is fixed on the lower mount 2 while being positioned with respect to the upper mold 4 (as shown in FIG. 1). On the upper and lower molds 4 and 5, there are provided cylindrical positioning pins and positioning holes (positioning means) (not shown) for aligning them. The positioning pin has a tapered tip.

Therefore, when the molding apparatus having the above-mentioned structure is used, even if the upper mold 4 is displaced with respect to the lower mold 5, the upper mold 4 is still as described above. Since it is held in a state of being pressed by the upper pedestal 1 and is not completely fixed, the upper mold 4 is gradually moved along the lower surface of the upper pedestal 1 while the positioning pins follow the positioning holes. The mold is clamped to the lower mold 5 while being positioned while sliding in the direction. For this reason, the positioning pin hardly forcibly enters the positioning hole in the state of being displaced as in the conventional case, and the positioning failure due to this wear is significantly reduced, and the number of times of component replacement is significantly reduced. In addition, it is not necessary to use an expensive material such as a cemented carbide corresponding to the above wear, and the cost is low. further,
Using this upper and lower molds, for example, when molding a resin sealing portion that covers an electronic element on a long lead frame, positioning defects due to wear of the positioning pins and positioning holes are extremely reduced as described above. The positional displacement of the upper and lower molds with respect to the lead frame is unlikely to occur, and appearance defects such as deformation and molding of the resin sealing portion are extremely reduced.

The pressing and holding of the upper die against the upper mount is
The configuration shown in FIG. 4 may be used. In this structure, the lift pins 17,
The compression spring 18 and the screw plug 19 are inserted, and the screw plug 19 presses the upper mold 20 against the upper mount 21 by the extension force of the compression spring 18.

In this embodiment, the lower mold is fixed to the lower mount and the upper mold is pressed and held against the upper mount. However, the present invention is not limited to this, and the upper mold is mounted on the upper mount. It may be fixed and the lower die may be pressed and held against the lower mount. Further, in the present embodiment, as the positioning means, a cylindrical positioning pin and a corresponding positioning hole having a circular shape in plan view are used, but the positioning block is not limited to this, and a positioning block having a substantially rectangular parallelepiped shape or the like may be used. Corresponding positioning grooves may be provided on the mating surfaces of the upper and lower molds. The tip of the positioning block has a tapered shape and fits along the wall surface of the positioning groove.

Further, in this embodiment, the upper mold is pressed and held against the upper base by the extension force of the cylinder 11, but the present invention is not limited to this, and the holding member 8 and the cylinder 11 are not limited to this. When the cylinder 11 is extended without being completely fixed, the upper mold is pressed and held against the upper frame by only the spring force of the compression spring 13, and when the cylinder 11 is contracted, A configuration may be adopted in which the pressing and holding of the upper die of the upper die is released.

[0019]

As is apparent from the above description, according to the present invention, the positioning pin almost never forcibly enters the positioning hole in a displaced state, and the positioning failure due to this wear is extremely reduced. In addition, the number of parts replacement is significantly reduced. In addition, it is not necessary to use an expensive material such as a cemented carbide corresponding to the above wear, and the cost is low. Further, since the positioning failure due to the wear of the positioning pin and the positioning hole is extremely reduced, the positional displacement of the upper and lower molds with respect to the lead frame is unlikely to occur, and the defective appearance such as deformation and molding of the resin sealing portion is significantly reduced. It

[Brief description of drawings]

FIG. 1 is a schematic view showing a molding apparatus for resin sealing of the present embodiment.

FIG. 2 is a partially cutaway side view showing details of a mounting structure for an upper die of an upper die.

FIG. 3 is an explanatory diagram for explaining a method of attaching a locking body to a slide shaft.

FIG. 4 is a partially cutaway side view showing a modified example of a mounting structure for an upper die of an upper die.

FIG. 5 is a side view showing a conventional molding device for resin sealing.

[Explanation of symbols]

 1 Upper mount 2 Lower mount 3 Press body 4 Upper mold 5 Lower mold 7 Slide shaft 10 Locking body

Claims (1)

[Claims] 1. A press main body having upper and lower pedestals capable of moving toward and away from each other, and upper and lower dies respectively disposed on the facing surfaces of the upper and lower pedestals, and a mating surface of the upper and lower dies. A device for forming a resin sealing portion on the mating surfaces of the upper and lower molds, wherein one of the upper and lower molds is provided with positioning means for aligning the upper and lower molds, The molding device for resin encapsulation is characterized in that it is held in a pressed state with respect to, and the other of the upper and lower molds is fixed to the frame.