JPH025931Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an encapsulation molding device for encapsulating and molding small electrical elements with synthetic resin material.

The typical configuration of this type of encapsulation molding device is shown in a front view in Fig. 1, but although it is not shown in the drawing, multiple pairs of cavities are arranged facing each other for each left and right block. Upper mold 1 with a mold
A lead frame with a small electric element (chip) attached is set on the joint surface of the upper mold 1 and the lower mold 2, and the mold is clamped by the operation of the pressure cylinder 3. A thermosetting synthetic resin material such as epoxy resin is supplied into the pot 4 installed in the holding frame 8 of the upper mold 1, and this molding material is transferred to the plunger 5.
The material is pressurized and injected into the cavity for encapsulation molding. The reciprocation of the plunger 5 with respect to the pot 4 is performed by a cylinder 6, and when the plunger 5, which is vertically installed on a movable frame 7 attached to the output rod side, descends, it is inserted into the pot 4 and pressurizes the resin material. .

By the way, in such an encapsulation molding device,
Synthetic resin materials such as epoxy resin are supplied to the pot through a special supply mechanism (not shown) from the resin material supply opening at the upper end of the pot. adhere to. Normally, the supply opening is chamfered, and the adhesive adheres to this chamfer and the upper end surface. When this adhered resin material hardens, it will eventually peel off and fall off and mix with the new material in the pot, reducing the quality of the molded product, worsening its appearance, and causing gate clogging and metallization. It has problems such as line breaks.

This invention aims to provide an encapsulation molding apparatus having a function of solving the above-mentioned conventional problems.

The feature of the encapsulation molding device provided by this invention is that it is equipped with a mechanism that abuts and engages with the resin material supply port of the pot and cuts and removes the resin material that has adhered and hardened to that part. A cutting tool for cutting and removing is arranged coaxially with the plunger, and a mechanism is coupled to move it forward and backward relative to the pot, so that it moves forward and backward relative to the pot in response to the pressurizing operation of the plunger, and is engaged with the resin material supply section for good centering. This allows for efficient cutting and removal.

This invention will be explained below with reference to embodiments shown in the drawings.

In FIG. 1, 9 is a rotary cutting tool whose lower end is shown. As will be clear from the description below, the rotary cutting tool 9 is rotated by a rotary drive mechanism provided between the movable frame 7 and a cover frame 7' attached to the lower surface of the movable frame 7.

FIG. 2 is a cross-sectional view horizontally showing the movable frame 7 portion of the apparatus shown in FIG. 1, mainly showing the rotational drive system of the cutting tool 9. Although FIG. 2 will be described later, the main part of this invention will first be explained with reference to FIG. 3, which shows the plane of FIG. 2-'.

FIG. 3 shows a sectional view in a state where the movable frame 7 is driven downward by the cylinder 6, the plunger 5 is press-fitted into the pot 4 fixed to the holding frame 8, and its tip 5' has entered the bottom of the pot 4. There is.

The cutting tool 9 is a hollow body whose lower tip is halved and has a tapered cutting edge, and is installed inside the hollow rotating body 10 via a pin 12.

This hollow rotating body 10 is rotatably inserted into a cylindrical space formed by the movable frame 7 and the cover 7'. Further, this hollow rotating body has a gear 10G attached to the center of its outer periphery, and this gear 10G meshes with the gear 10G of the other hollow rotating body 10 so that all the other gears 10G also form a gear transmission system. They mesh and transmit mutual rotation. The rotational drive of each of these gears 10G is the rightmost gear 10G.
is engaged with the rack 15, and the reciprocating movement of the rack 15 is performed.

The racks 15 are arranged on both sides of the movable frame 7 as shown in FIG. It is maintained so that it does not come off. The guide frame 16 is fixed to the movable frame 7 with fixing screws 17. In this way, it is easy to
In FIG. 3, the rack 15 reciprocates in a direction perpendicular to the plane of the paper, and in FIG. This is done by That is, the output rod 19 of the air cylinder 20 is connected to the connector 1.
8 to the left end of the rack 15.

In Fig. 2, the transmission system of the gear 10G is the movable frame 7.
They are arranged in four rows in the vertical direction on the inside of the rack 15, and correspond to the four pots 4 (four rows) in FIG.
Since the gears 0G are engaged, all the gears 10G are driven to rotate in a reciprocating manner by the reciprocating movement of the rack 15. In FIG. 2, the rack 15 and its reciprocating drive systems 18, 19, and 20 are installed in two series, but this is because the load increases due to the large number of gears 10G. If all gear transmission systems in each row mesh with each other, gear 10G
The drive system is adjusted so that the respective rotary drive torques do not collide. Alternatively, the gear transmission system of each row may be disconnected midway. This requires consideration of the pot arrangement as such.

The hollow rotating body 10 is rotated by the rotation drive mechanism as described above, and the cutting tool 9 is rotated. Further, a coiled compression spring 11 is interposed inside the hollow rotating body 10 to bias the cutting tool 9 downward.
The cutting tool 9 is configured to be rotationally transmitted to the hollow rotary body 10 via a pin 12, and is configured to allow a certain relative displacement in the axial direction. Therefore, as shown in FIG. 3, when the cutting tool 9 abuts and engages with the upper end of the pot 4, that is, the chamfered portion of the synthetic resin material supply port, the cutting tool 9 properly adapts and rotates to cut and adhere to the supply port. Remove hardened material.

In the above structure, the operation will be explained. First, in the state shown in FIG. 1, a synthetic resin material is supplied to a large number of pots 4 by a supply mechanism (not shown).

Next, the movable frame 7 is lowered by the operation of the cylinder 6, the plunger 5 is inserted into the pot 4, and a pressurized injection operation is performed. When the plunger 5 is inserted into the pot 4 until its tip 5' penetrates the bottom of the pot 4 and the pressurized injection operation is completed, the cutting tool 9 is inserted into the material supply opening (chamfered part) of the pot 4. come into contact with

This abutting engagement is performed by elastic biasing of the compression spring 11 and is adapted to the chamfered portion. Figure 3 shows exactly this state, and in this state the air cylinder 2
0 is activated and the rack 15 is reciprocated, the cutting tool 9 is rotated integrally with the hollow rotating body 10, and the hardened resin adhering to the supply opening is cut and removed.
Next, when the plunger 5 is pulled up by the movable frame 7, the cutting tool 9 is also removed from the pot 4. Compressed air is then blown onto the upper end of the pot 4 using a blower (not shown) or the like to remove the cut material.

As detailed above, the feature of the mechanism for removing adhered and hardened resin material according to this invention is that the cutting tool is of a rotary cutting type, is arranged coaxially with the plunger 5, and operates in conjunction with the operation of the plunger 5. It is in the point of doing. That is, since it is coaxial with the plunger, there is no need for a special centering mechanism, and it is sufficient to simply move it forward and backward with respect to the pot. Furthermore, especially in the case of the embodiment shown in FIG. 3, since the plunger 5 is constructed with a cutting tool inserted through it, the cutting can be performed in conjunction with the pressurized injection operation of the plunger, thereby ensuring efficient removal work. .

However, this invention is not limited to a method that is linked to such a pressurized injection operation. For example, as shown in FIG.
Modified embodiments also include configurations in which the parts are removable. FIG. 4 shows the same cross section as FIG. 3, and parts with the same functions as those in FIG. A penetrating guide hole 7H is provided above the movable frame 7 so that the movable frame 7 can be removed. The movable frame 7 may be moved forward and backward with respect to the pot by the same mechanism as the plunger 5, or may be operated by a separate movement mechanism. Fourth
In the case of the figure as well, the cutting tool 9 is disposed coaxially with the plunger 5 so that the plunger 5 can penetrate the cutting tool 9.

In addition to the modified embodiment shown in FIG. 4, various modified embodiments can be given for the configuration of each part. In particular, the configuration and shape of the cutting tool are not limited to the illustrated example, and may be configured integrally with the hollow rotating body, for example.

Furthermore, the rotational drive system of the cutting tool is other than the gear system or the rack and pinion type, for example, a rotation drive system in which a belt that is wound and rotated by a motor rotates in tandem, or a system in which the rotation of the motor is decelerated and transmitted directly to the gear system. etc. can be used.

As shown in Figs. 1 and 2, the illustrated pot is a pot cutting/removal mechanism (scraper) in a so-called runnerless type enclosure device, but this invention can also be implemented as a scraper for pots other than runnerless type. .

As detailed above, the encapsulation molding device provided by this invention is equipped with a function to cut and remove the adhered and hardened resin material, so it is possible to prevent the gate from clogging due to the adhered and hardened material falling off, or to cut the gold wire or disturb the appearance. The problems of deterioration and quality deterioration of molded products are solved. In particular, in the case of the embodiment shown in FIG. 3, the cutting and removal is performed in conjunction with the pressurized injection operation by the plunger, and in particular, the removal after the pressurized injection by the plunger is performed after molding, so there is no possibility that it will fall off and get mixed in during the molding process. It is a simple and efficient removal mechanism. It can greatly contribute to automation.

Furthermore, the cutting tool is arranged coaxially with the plunger, which facilitates operation and is useful for simplifying the structure.

[Brief explanation of the drawing]

The drawings show an embodiment of the encapsulating device according to this invention, and FIG. 1 is a front view showing the appearance of the entire encapsulation molding device, and FIG. 3 are longitudinal cross-sectional views showing the structure of the cutting and removing mechanism according to this invention, and FIG. 4 is a view showing a modified embodiment. 1...upper mold, 2...lower mold, 4...pot, 5...
...Plunger, 6...Cylinder, 7...Movable frame,
7'... Cover, 8... Holding frame, 9... Cutting tool,
10...Hollow rotating body, 10G...Gear, 11,1
3... Compression spring, 12... Pin, 15... Rack, 18... Connector, 20... Air cylinder.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) When encapsulating and molding a plurality of small electric elements with a synthetic resin material using a mold in which a plurality of cavities are arranged, In this apparatus, the synthetic resin material is supplied into a pot, and is injected under pressure into each cavity by a plunger inserted into the pot to form the resin. a cutting tool that rotates and removes the synthetic resin material adhering to the resin supply port; a forward/backward drive mechanism that moves the cutting tool forward and backward with respect to the synthetic resin supply port of the pot; An encapsulation molding device comprising: a rotational drive mechanism that rotates a cutting tool while in contact with a supply port. (2) The encapsulation molding apparatus according to claim 1, wherein the plunger and the cutting tool are coupled so that the plunger penetrates the cutting tool, and the mechanism for driving the cutting tool forward and backward is configured by the reciprocating mechanism of the plunger. .