JPH11103153A - Thermocompression bonding apparatus for circuit connection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermocompression bonding apparatus in which connection can be performed with high reliability even by using a heating tool whose lowering speed is small, by a method wherein a two-port changeover solenoid valve which excludes a scanning pressure, and a timer whose operation is started by the signal of a lower-dead-center detecting switch and which operates the two-port changeover solenoid valve after a set time is installed, are installed near an air cylinder in a lower-side flow passage. SOLUTION: A two-port changeover valve 8 is normally closed, it opens a flow passage by a signal from a timer 9, and it is attached between the lowering-speed control valve 6 of a cylinder lower-side flow passage 4 and a cylinder 1. While a heating tool 14 is being lowered, the solenoid valve 8 is closed, and the discharge air on the lower side of a piston 2 is passed through a flow-rate throttle valve 6b so as control a lowering speed. Before the heating tool 14 comes into contact with a work 15, a lower-dead-center detection part 11 which is attached to a moving plate 12 and which is lowered together with the heating tool 14 turns on a switch 10. When the heating tool 14 comes into contact with the word 15, the two-port changeover solenoid valve 8 is opened so as to match a timing, the remaining pressure air on the lower side of the piston 2 is discharged suddenly, and a sufficient set pressure can be applied to the work 15 from the time of a heating operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass substrate or a printed wiring board used for a liquid crystal display or the like.
The present invention relates to a connection device for connecting a circuit board such as a PC via an anisotropic conductive adhesive film.

[0002]

2. Description of the Related Art An apparatus for connecting electrodes of opposing substrates using an anisotropic conductive adhesive film is disclosed in
As disclosed in Japanese Patent No. 89492, there is a method of heating and pressurizing a work by a heating tool having a pressurizing mechanism, and an air cylinder is generally used as the pressurizing mechanism. The air cylinder can adjust the pressure of the inflowing air to pressurize the work at a predetermined pressure, and can adjust the flow rate of the air flowing out of the air cylinder to adjust the moving speed of the piston. Thus, the pressing force applied to the work and the speed at which the heating tool is pressed are controlled.
With this connection method, the pressure applied to the work is determined by the difference between the air pressure on the upper side and the air pressure on the lower side of the piston in the air cylinder. Also, when the piston descends and pressurizes the work, to prevent the heating tool from impulsively hitting the work, reduce the air outflow velocity below the piston and lower the air cylinder so that the piston descends slowly. A lowering speed control valve is installed in the lower flow path. The descent speed adjustment valve necessarily increases the air pressure under the piston to narrow the outflow passage of air under the piston, and the pressure applied to the work when the heating tool descends and comes into contact with the work Does not reach a predetermined pressure, but after contact and the piston stops, the pressure gradually increases as the pressure (residual pressure) of the air below the piston drops, and when the residual pressure disappears, a predetermined pressure is obtained. On the other hand, when the anisotropic conductive adhesive film is mainly composed of a thermosetting resin, the chemical reaction rapidly proceeds when the temperature rises due to the heating tool contacting the work,
Cures within seconds. At this time, if the pressure applied to the work is insufficient due to residual pressure remaining, there has been a problem that connection reliability is reduced.

[0003]

SUMMARY OF THE INVENTION The present invention is an improvement on this point, and it is an object of the present invention to provide a highly reliable circuit connection method which can provide a sufficient pressing force even if the lowering speed of the heating tool is low. .

[0004]

That is, the present invention provides an air cylinder (1) for applying pressure by moving a heating head (18) up and down, and a heating tool lowering speed adjusting valve installed in a flow path below the air cylinder. (6), a heating tool rising speed adjusting valve (5) installed in the air cylinder upper flow path, a three-port two-way switching solenoid valve (7) for switching a flow direction of air flowing into the cylinder, and a heating tool ( 14) works (1)
5) Bottom dead center detection switch (1
In the heating and pressurizing device consisting of 0), the operation is started by a two-port switching solenoid valve (8) for removing residual pressure near the air cylinder in the lower flow path of the air cylinder and a signal from the bottom dead center detection switch. And a timer (9) for operating the two-port switching electromagnetic valve (8) after a set time is provided.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing embodiments. In FIG. 1, reference numeral 18 denotes the movable plate 1.
2 is a heating head fixed to 2 and comprises a heater 13 and a heating tool 14 and is moved up and down by a piston 2 of an air cylinder 1. The spring 17 supports the weight of the movable plate 12 and the heating head 18, and
Even if the air is released, it will not fall down.
The work 15 is placed on a base 16 and is heated and pressed by pressing a heating tool 14 heated by a heater 13 with the pressure of the air cylinder 1. 7 is 3 port 2
A direction switching solenoid valve for switching the air flow path to the air cylinder. Numerals 5 and 6 denote valves for adjusting the rising and falling speeds of the heating head 18, which are provided with check valves 5a and 6a and flow restrictors 5b and 6b, respectively. A normally closed type two-port switching solenoid valve 8 is provided in the cylinder lower passage 4 in conjunction with a timer 9. 10 is a heating head 18
Is a switch for detecting the bottom dead center and sending a signal to the timer. The 2-port switching solenoid valve 8 is opened when the timer set time has elapsed since the bottom dead center detection switch was turned on.

[0006] Compressed air from a compressor or the like normally passes through the cylinder lower flow path 4 to push the piston 2 upward. Here, in order to lower the heating head 18, the three-port two-way switching electromagnetic valve 7 is switched by operating a switch (not shown) so that compressed air flows through the cylinder upper passage 3. At this time, the heating tool raising speed adjusting valve 5 passes through the check valve 5a having a small flow resistance and does not pass through the flow restrictor valve 5b having a large flow resistance. When air flows into the upper part of the cylinder and the piston starts to descend, the air below the piston is discharged to the outside through the cylinder lower flow path. At this time, the check valve 6a of the heating tool lowering speed adjusting valve 6 cannot pass, but passes through the flow restrictor 6b having a large flow resistance. Therefore, the pressure of the air below the piston rises, the air is slowly discharged, and the heating tool is discharged. Lowering speed can be reduced. Therefore, when the descent speed is reduced, the air pressure below the piston increases, and the pressure applied to the work when the heating tool comes into contact with the work and stops is reduced by the pressure (residual pressure) below the piston. As the residual pressure is discharged, the pressing force applied to the work gradually increases.

The two-port switching solenoid valve 8 according to the present invention is normally closed, and opens the flow path in response to a signal from the timer 9. 1). While the heating tool is descending, the solenoid valve 8 is closed, and the exhaust air below the piston passes through the flow restrictor 6b, so that the descending speed can be controlled. Next, shortly before the heating tool comes into contact with the workpiece, the bottom dead center detection unit 11 attached to the movable plate 12 and descending with the heating tool turns on the bottom dead center detection switch 10. The timer 9 adjusts and sets the time from when the bottom dead center detection switch 10 is turned ON to when the heating tool comes into contact with the workpiece in accordance with the descending speed of the heating tool. In this way, when the heating tool comes into contact with the workpiece, the 2-port switching solenoid valve is opened in a timely manner, and the residual pressure air below the piston is rapidly discharged, so that a sufficient set pressure is obtained from the start of heating. Can be applied to the work. In addition,
If the lowering speed of the heating head 18 is relatively fast and the time from when the bottom dead center detection switch 10 is turned on to when the heating tool contacts the workpiece is extremely short, the timer 9 is omitted and the bottom dead center detection switch is omitted. The two-port switching electromagnetic valve 8 may be opened directly by an ON signal.

[0008]

By installing the two-port switching solenoid valve of the present invention, the residual pressure can be rapidly eliminated even when the descent speed of the heating tool is reduced with relatively high air pressure. It is possible to start up sufficiently to the set pressure. In addition, by operating the timer with the bottom dead center detection switch, the time from when the bottom dead center detection switch is turned on to when the tool comes into contact when the tool descent speed is low is set. Abruptly eliminated, it was possible to maintain a constant speed during the descent and to start the pressing force applied to the workpiece at the same time as contact to the set pressure sufficiently quickly, making it possible to make a highly reliable connection. .

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a thermocompression bonding apparatus showing one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Air cylinder 2 Piston 3 Upper cylinder flow path 4 Lower cylinder flow path 5 Heating tool rising speed adjusting valve 6 Heating tool lowering speed adjusting valve 7 3-port 2-way switching solenoid valve 8 2-port switching solenoid valve 9 Timer 10 Bottom dead inspection Outgoing switch 11 Bottom dead center detector 12 Movable plate 13 Heater 14 Heating tool 15 Work 16 Base 17 Spring 18 Heating head 5a Check valve 5b Flow restrictor 6a Check valve 6b Flow restrictor

Claims (1)

[Claims] An air cylinder (1) for applying pressure by moving a heating head (18) up and down, a heating tool lowering speed adjusting valve (6) installed in an air cylinder lower flow path, and an air cylinder upper flow. A heating tool ascending speed adjusting valve (5) installed on the road, a 3-port 2-way switching solenoid valve (7) for switching the flow direction of air flowing into the cylinder, and a heating tool (1).
4) A heating and pressurizing device comprising a bottom dead center detection switch (10) for detecting a position where the work (15) is pressed,
A two-port switching solenoid valve (8) for removing residual pressure near the air cylinder in the lower flow path of the air cylinder, and an operation is started by a signal from the bottom dead center detection switch.
A thermocompression bonding device for circuit connection, comprising a timer (9) for operating a port switching solenoid valve (8).