JPH0422038B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an apparatus for manufacturing thick film circuits that can be used in radio receivers, television receivers, communication equipment measuring instruments, and the like.

Conventional structure and problems Conventionally, thick film circuits were generally produced by forming conductor paste, resistor paste, etc. onto a substrate into the desired shape using screen printing, and then drying and baking. . However, since the screen printing method uses a mask pattern, it takes time to replace the mask pattern and to clean the mask pattern and the squeegee, making it unsuitable for small-lot production or when there are many product changes.

In response, a method has been devised and proposed in which the paste is directly extruded from a nozzle without using a mask pattern, and the paste is drawn on a moving substrate. This method was excellent in its own way and was effective in some cases for solving the above problems.
However, since actual substrates have "warpage" or "twisting", there is a problem in that the film thickness and line width of the thick film paste formed on the substrate are not constant. This has been a cause of conductor breaks and short circuits when forming fine patterns. Furthermore, when the resistor is fired, the resistance value varies.

OBJECTS OF THE INVENTION The present invention eliminates the above-mentioned conventional drawbacks and provides a thick film circuit drawing apparatus capable of drawing fine patterns with high precision.

Structure of the Invention In order to solve the above-mentioned conventional drawbacks, the present invention has a thick film paste discharge hole at the tip of the nozzle and a touch piece for keeping the distance between the substrate and the discharge hole constant, and the touch piece is The contact piece is adjacent to the discharge hole and is installed in front of the discharge hole with respect to the relative movement direction of the nozzle during drawing, and the touch piece is located at least on the substrate with respect to the relative movement direction of the nozzle during drawing. This is a thick film circuit drawing device in which the frontmost part that comes into contact is an inclined surface, and the contact piece contacts the substrate during drawing, and has the effect of keeping the distance between the substrate and the discharge hole constant, and It is installed forward in the direction of relative movement of the nozzle so as not to come into contact with the thick film paste.
The contact part of the contact piece with the substrate is generally flat, and the frontmost part is an inclined surface with respect to the direction of relative movement of the nozzle, so it does not stick to the thick film pattern that has been printed and fired on the substrate in advance. It is designed so that it will not cause any damage.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. The drawing nozzle 1 is fixed to a nozzle elevating section 2, and is further fixed to a Y-axis drive section 3 of an X-Y drive device.
It is fixed to the X-axis drive section 4 via. In order to discharge the thick film paste 5, the drawing nozzle 1 is pressurized by air pressure, and the electromagnetic valve 6 controls pressurization and depressurization by the air pressure. The substrate 7 is vacuum-adsorbed by a substrate fixing table 8 that can move up and down, and a solenoid coil 9 generates pressure to the nozzle. 10
A control device having a built-in microprocessor controls the movement of the nozzle 1, the opening and closing of the solenoid valve 6, and the vertical movement of the substrate fixing table 8. A discharge hole 11 for discharging the thick film paste 5 is provided at the tip of the nozzle 1, and a rectangular diamond chip 12 is adhered thereto. The diamond chip 12 is a contact piece for keeping the distance between the tip of the discharge hole 11 and the substrate 7 constant, and an adhesive fillet 13 is formed in front of the drawing direction to form a contact piece together with the diamond chip 12. There is. This fillet 13 essentially forms the slope of the tentacle.

Now, in order to draw a thick film circuit on the substrate 7, the nozzle 1 is lowered so that the diamond chip 12 touches the substrate 7, and then
At least one of the shaft drive units 3 is actuated to move the nozzle. At this time, thick film paste 5
The electromagnetic valve 6 is opened at a preset timing to pressurize the inside of the nozzle 1 with air pressure so that the drawing circuit 14 is formed by discharging the nozzle. Next, the electromagnetic valve 6 is closed to stop discharging the thick film paste 5, and at about the same time the nozzle 1 is raised to a desired length. At this time, even if the fillet 13 intersects with the fired thick film pattern 15 previously formed on the substrate 7, the thick film pattern 15 may be damaged by the diamond chip because the fillet 13 is formed in front of the diamond chip. You can draw circuits overlapping each other without any problems. In addition, the diamond chip 1 on the board fixing stand 8
The pressing force on the solenoid coil 9 is adjusted by the electric power applied to the solenoid coil 9, and is set to about 50 g in the embodiment. Further, the diamond chip 12, which is a part of the tentacle, is inserted into a fixing hole at the tip of the nozzle and is further bonded, so that it is firmly fixed.

Next, other embodiments will be described with reference to FIGS. 3 to 5. FIG. 3 shows a second embodiment of the present invention, in which a chamfer 16 is provided at the tip of the diamond chip 12 to prevent damage to the fired thick film pattern previously formed on the substrate. . FIG. 4 shows a third embodiment of the present invention, in which an effect similar to that of the second embodiment is obtained by forming a contact piece with an inclined portion 17 integrated with the nozzle 1 and a diamond chip 12. FIG. 5 shows a fourth embodiment of the present invention, in which the tip corner edge of the diamond chip 12 is chamfered in a slight arc to form an inclined surface. Note that ruby, tungsten carbide, or the like may be used in the parts where diamond chips are used in the embodiments.

Effects of the Invention As explained above, according to the present invention, a constant drawn film thickness can be obtained by the tentacles, and at the same time, since the tentacles always precede the thick film paste discharge hole, the thick film paste is drawn. Since there is no contact with
It has an excellent effect of not damaging the fired thick film pattern previously formed on the substrate, and has great industrial utility value.

[Brief explanation of drawings]

Figure 1 is a front view showing one embodiment of the present invention, Figure 2 is a front view showing one embodiment of the present invention;
The figure is a cross-sectional view of a nozzle portion in one embodiment of the present invention, and FIGS. 3, 4, and 5 are cross-sectional views of a nozzle tip in other embodiments of the present invention. DESCRIPTION OF SYMBOLS 1... Nozzle, 5... Thick film paste, 7... Substrate, 1
1...Discharge hole, 12...Diamond chip, 13...
Fillet portion, 14...drawing circuit, 16...chamfered portion.

Claims (1)

[Claims] 1. A thick film paste discharge hole and a touch piece are provided at the tip of the nozzle, and the touch piece is adjacent to the discharge hole, and the touch piece is further away from the discharge hole with respect to the relative movement direction of the nozzle during drawing. The thick film circuit drawing apparatus is also provided at the front, and at least the frontmost portion of the contact piece that contacts the substrate with respect to the direction of relative movement of the nozzle is an inclined surface.