JPH0663992A - Liquidlike resin metering apparatus - Google Patents

Abstract

PURPOSE:To accurately meter irrespective of viscosity of resin by providing metering cylinders having equal sectional areas to suck resin at storage tanks when two-liquid liquidlike resins is supplied to a liquidlike resin injection molding machine, and equalizing retracting speed ratio of pistons to a two-liquid mixture ratio. CONSTITUTION:Resins A, B are respectively contained in first, second resin tanks 5, 6, and pneumatic pressure is applied. Sectional areas of metering cylinders 1, 3 are made equal, and a speed ratio of servo motors 2, 4 for driving the pistons is equalized to a mixture ratio of the resins A, B. The resin is metered by opening resin metering valves 7, 8, closing injection metering valves 9, 10, simultaneously driving the motors 2, 4, and evacuating to fill the resins A, B in the cylinders 1, 3. Then, the resins, A, B are transferred to a mixing agitating cylinder 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring device for measuring a two-component liquid epoxy resin.

[0002]

2. Description of the Related Art In recent years, members related to electronic parts have become lighter, thinner, shorter, and smaller, and for example, in the field of coil parts, the surface mounting of substrates tends to increase. Therefore, electronic parts have been sealed and molded with an insulating material to ensure reliability. Conventionally, a thermosetting resin used for sealing ICs and the like has been used for this type of sealing resin, but this type of resin is 150 to 180 at the time of molding.
Since a high temperature of [deg.] C. and a high pressure of 30 to 100 kg / cm < ² > have to be applied, there is a possibility that the characteristics of the electronic component may be impaired.

In order to avoid the damage of high temperature and high pressure at the time of molding as described above, a liquid thermosetting resin is dropped onto an electronic component and cured at a relatively low temperature such as around 120 ° C. Although a bonding method is adopted, this bonding method does not cause performance deterioration of the electronic component due to high temperature and high pressure, but it takes a long time to cure, and automation of mounting is difficult depending on the shape of the electronic component. there were.

In order to solve the above problems in the bonding method, the thermosetting resin is filled in the cavity of the sealing die at a relatively low pressure (3 to 10 kg / cm ² ) and the temperature is relatively low (120 ° C.). Molding method of curing at ~ 150 ° C)
That is, the injection molding method has been adopted.

The liquid encapsulating resin used in the above injection molding method differs depending on the characteristics of the electronic component to be encapsulated, but in reality, a two-component resin is predominantly used. The two-liquid type resin is manually measured by using, for example, an electronic balance or the like, set in an injection tank, and then injected and filled in a mold.

[0006]

The above-mentioned injection molding method is the most recommended sealing means at present, but the resin viscosity increases in the tank in which the two liquids are premixed, and molding is hindered. There is a risk. Therefore, in order to mix the two liquids immediately before injection, a measuring device capable of measuring the resin with high measuring accuracy is required regardless of the resin viscosity.

The present invention has been made to solve the above problems, and provides a liquid resin measuring device which can completely automate a liquid resin injection molding system and obtain a high quality injection molded product.

[0008]

A liquid resin measuring apparatus of the present invention is a measuring cylinder for sucking resin from a tank storing each resin when supplying a two-liquid type liquid resin to a liquid resin injection molding apparatus. Are provided, the cross-sectional areas of these metering cylinders are made equal, and the speed ratio of the pistons retracting due to the suction in each cylinder is made equal to the mixing ratio of the two liquids.

[0009]

In the liquid resin measuring device of the present invention having the above structure, the measuring cylinders have the same sectional area.
Since the retreat speed ratio of the piston in each cylinder is made equal to the mixing ratio of the two liquids, the volume ratio of the liquid resin suction-filled in each measuring cylinder becomes equal to the mixing ratio of the two liquid mixing resin.

[0010]

1 is a schematic sectional view showing an outline of an embodiment of the present invention, and FIG. 2 is a schematic sectional view of a mixing and stirring cylinder portion in a liquid resin molding system. In FIG. 1, the first
The measuring cylinder 1 has a piston 1a driven by a servomotor 2, and the second measuring cylinder 2 has a piston 2a driven by a servomotor 4. First
The inside of the measuring cylinder 1 is communicated with the bottom surface of the first resin tank 5 by a pipe line 7 ′ equipped with a resin measuring valve 7, and the inside of the second liquid measuring cylinder 3 is connected to the bottom surface of the second resin tank 6 with the resin. It is communicated by a line 8'comprising a metering valve 8. The pipe lines 7'and 8'extend beyond the respective metering cylinders 1 and 3 and communicate with the mixing and stirring cylinder 9 via injection metering valves 10 and 11.

In FIG. 2, a stirring screw 12 is concentrically provided in the mixing and stirring cylinder 9, and a metering injection servomotor 13 for driving the stirring screw is provided outside one end of the mixing and stirring cylinder 9. ing.
At the other end of the mixing and stirring cylinder 9, a pipe line 9a reaching an injection nozzle (not shown) is projected, and a resin pressure sensor 14 is provided in this pipe line 9a.

In the system having the above structure, the first resin tank 5 contains the A resin, and the second resin tank 6
B resin is stored inside. These tanks have
For example, an air pressure of about 6 kg / cm ² is applied. Further, the cross-sectional area of the first measuring cylinder 1 and the cross-sectional area of the second measuring cylinder 3 are made equal, and the pistons 1a of these measuring cylinders, the servomotor 2 for driving the piston 3a, and the servomotor 4 are The speed ratio is made equal to the mixing ratio of A resin and B resin. For example, if the mixing ratio of A resin and B resin is 100: 17, the speed ratio is also set to 100: 17.

The resin metering valves 7 and 8 are opened and closed at a timing described later by an operating mechanism (not shown). The injection metering valves 10 and 11 are also opened and closed in the same manner.

In the embodiment having the above construction, the A resin and the B resin are weighed as follows. When the resin metering is started, first, the resin metering valves 7 and 8 are opened, and the injection metering valves 9 and 10 are closed. At the same time, the pistons 1 of the first measuring cylinder 1 and the second measuring cylinder 3 respectively
a and 3a are driven by the servomotors 2 and 4 and move backward. As a result, the resins in the resin tanks 5 and 6, that is, the A resin and the B resin, are sucked and filled in the first and second measuring cylinders 1 and 3. The cross-sectional areas of the respective measuring cylinders 1 and 3 are made equal, and the reciprocating speed ratios of the pistons 1a and 3a thereof are set to A resin, B as described above.
Since the mixing ratio of the resins is made equal, the volume ratio of the A resin and B resin filled in each cylinder is equal to the mixing ratio. The measuring cylinder 1 is placed in the mixing and stirring cylinder 9.
To transfer the A resin and B resin in 3 and 3 and to fill the A resin and B resin into the mixing and stirring cylinder 9 at a predetermined mixing ratio, the procedure is as follows. That is, the resin metering valves 7, 8
Is closed, the injection metering valves 10 and 11 are opened, and the pistons 1a and 3a of the metering cylinders 1 and 3 are driven and moved forward by the servomotors 2 and 4. At this time, the screw 12 in the mixing and stirring cylinder 9 is rotated by the metering injection servomotor 13 in the backward direction, that is, the suction direction.

According to the above, the measuring cylinders 1, 3
The resin A and the resin B, which had been filled in the mixture at a ratio equal to the mixing ratio, are filled in the mixing and stirring cylinder 9. The rotation speed of the screw 12 is the same as that of the metering injection servomotor 1.
3, the speed is controlled by the measuring cylinders 1, 3
The pressure in the mixing and stirring cylinder 9 is controlled so that it is actually maintained at, for example, ² to 3 kg / cm ² to the extent that the pressure does not drop excessively. The pressure in the mixing and stirring cylinder 9 is monitored by the pressure sensor 14, and the pressure sensor 1
The output of 4 is fed back to the servomotors 2 and 4 for driving the pistons 1a and 3a of the first and second measuring cylinders 1 and 3, and controls them.

The measuring device of the present invention having the above-mentioned structure can obtain the measuring accuracy within ± 1%. Further, since the measurement is performed by driving the piston in the measuring cylinder, even if the viscosity of the resin changes in a wide range such as 10 ps to 500 ps, accurate measurement can be performed regardless of the change.

[0017]

As is apparent from the above, the liquid resin measuring device of the present invention can perform high-precision measurement regardless of the change in the viscosity of the liquid resin to be measured. You can improve your sex. Further, the liquid resin can be continuously measured, and the automation of the two-liquid mixed resin injection molding system is easy.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an outline of an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a mixing and stirring cylinder portion in a liquid resin molding system.

[Explanation of symbols]

 1, 3 ... Metering cylinder 1a, 3a ... Piston 2, 4 ... Servo motor 5, 6 ... Resin tank 7, 8 ... Resin metering valve 9 ... Mixing and stirring cylinder 10, 11 ... Metering injection valve 12 ... Screw 13 ……… Metering injection servo motor 14 ……… Pressure sensor

Claims (1)

[Claims] 1. When supplying a two-liquid type liquid resin to a liquid resin injection molding apparatus, a measuring cylinder for sucking the resin from a tank storing each resin is provided, and the cross-sectional areas of these measuring cylinders are equal. Then, in each cylinder, the speed ratio of the piston retracting due to the suction is
A liquid resin measuring device characterized in that the liquid mixing ratio is made equal.