Towa Corporation

Other

Yoshihisa Kawamoto

Michio Osada

Makoto Matsuo

Koichi Araki

Keiji Maeda

Takaki Kuno

Yoshiji Shimizu

Satoshi Nihei

Susumu Yamahara

Toshiyuki Nishimura

A die used for molding an electronic component with resin includes a fixed, top die and a movable, bottom die and at least has a surface contacting a melted resin material that is electroplated with nickel-tungsten alloy. This plating can provide releaseability of a resin-molded body and the like superior to hard-chromium plating to allow an ejector pin to efficiently eject and release the resin-molded body from the die.

Die used for resin-sealing and molding an electronic component

In an apparatus for molding resin to seal electronic parts, an internal die space defined at least by pots, cull portions, resin passages and cavities when an upper mold section and a lower mold section are closed, is cut off or sealed from the exterior atmosphere. Thereupon the die space is evacuated using a first evacuation by a vacuum source and a second or instantaneous evacuation by an instantaneous evacuation mechanism. The vacuum source for the first evacuation may be an active vacuum pump, while the instantaneous evacuation mechanism may be a vacuum tank that has been previously pumped down, for example. Using this apparatus, it is possible to quickly improve the degree of vacuum in the internal die space by efficiently and reliably discharging air, moisture and gas from the internal die space to the exterior due to a synergistic action of the evacuation and the instantaneous evacuation. Consequently, the formation of voids in resin molded members is prevented.

Method of and apparatus for molding resin to seal electronic parts

In a method of sealing electronic parts with molded resin, a hollow sealing member is arranged on a mold surface of an upper mold section of a mold comprising the upper mold section and a lower mold section, so that the hollow sealing member is pressurized and expanded to convexly project from the mold surface of the upper mold section. In this state, the lower mold section is upwardly moved to be brought into contact with the expanded hollow sealing member. Further, an internal space portion, including pots, cull portions, resin passages and cavities, which is enclosed with the expanded hollow sealing member is set in a state isolated from the exterior when the upper mold section and the lower mold section are closed, so that the internal space portion is forcibly evacuated in this state. Thus, air, moisture and gases are efficiently and reliably suction-discharged from the internal space portion, whereby the internal space portion is set at a prescribed degree of vacuum. Consequently, it is possible to avoid contamination of air, moisture and the like in melted resin materials, as well as to prevent formation of voids in resin-sealed compacts.

Method of sealing electronic parts with molded resin and mold employed

A fixture for fixing an annular upper air isolation member which is provided around an outer side of an upper mold section to an upper mounting plate is released, thereby rotating the air isolation member by a rotational member and fixing the same by a rotational position regulating member. An upper chase unit is exchanged through an upper opening which is defined by the upper mounting plate and the rotated air isolation member. A lower chase unit is also exchanged in a similar manner. Due to this structure, a sealing mechanism for a resin sealing/molding apparatus for electronic parts which can readily and quickly exchange a mold in response to small lot production of various types of products is provided.

Resin sealing/molding apparatus for electronic parts

In a method of molding resin to seal electronic parts, an internal die space defined at least by pots, cull portions, resin passages and cavities when an upper mold section and a lower mold section are closed, is cut off or sealed from the exterior atmosphere. Thereupon the die space is evacuated using a first evacuation by a vacuum source and a second or instantaneous evacuation by an instantaneous evacuation mechanism. The vacuum source for the first evacuation may be an active vacuum pump, while the instantaneous evacuation mechanism may be a vacuum tank that has been previously pumped down, for example. According to this method, it is possible to quickly improve the degree of vacuum in the internal die space by efficiently and reliably discharging air, moisture and gas from the internal die space to the exterior due to a synergistic action of the evacuation and the instantaneous evacuation. Consequently, the formation of voids in resin molded members is prevented.

Method of molding resin to seal electronic parts using two evacuation

In an apparatus for molding resin to seal an electronic part, a sealed space portion is formed between molding surfaces of an upper mold section and a lower mold section by covering an outer side periphery of a pot, a resin path and a cavity. A resin tablet is heated at its bottom portion and peripheral portion in the pot of the lower mold section to expand upwardly from its top portion. Air and moisture included inside the resin tablet is expelled into the sealed space portion which is evacuated including any air and moisture inside the sealed space portion, whereby the formation of voids in the molded resin body is avoided.

Resin molding apparatus for sealing an electronic device

In a method for molding resin to seal an electronic part, a sealed space portion is formed between molding surfaces of an upper mold section and a lower mold section by covering an outer side periphery of a pot, a resin path and a cavity. A resin tablet is heated at its bottom portion and peripheral portion in the pot of the lower mold section to expand upwardly from its top portion. Air and moisture included inside the resin tablet is expelled into the sealed space portion which is evacuated including any air and moisture inside the sealed space portion, whereby the formation of voids in the molded resin body is avoided.

Growing community of inventors

Kyoto, Japan

Yoshihisa Kawamoto