JP2629906B2 - Through-hole printing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a through-hole printing apparatus and a printing method used for manufacturing a printed wiring board.

2. Description of the Related Art In recent years, some hybrid integrated circuits have circuits formed on both front and back surfaces of a printed wiring board for higher density, and holes formed in the board as means for making electrical connection between both sides of the board. A conductor paste is applied to the side wall of the substrate by a printing technique to form a through hole.

Hereinafter, a conventional through-hole printing apparatus will be described. FIG. 2 is a configuration diagram of a conventional through-hole printing apparatus, wherein 1 is a substrate which is a substrate to be printed, 2 is a hollow support base which supports the lower surface of the substrate 1 and can move up and down, and 3 is a hollow support base 2 This is a hose connecting the vacuum pump and the support base 2 to suck the part. Reference numeral 4 denotes a screen plate fixed on the substrate 1 at a predetermined interval, 5 denotes a squeegee which is installed above the screen plate 4 and moves while pressing the screen plate 4 against the substrate 1, and 6 denotes an interlock with the squeegee 5. The scraper 7 moves and is a conductor paste. Reference numeral 8 denotes a positioning device, and the upper surface of the positioning device 8 is set so as not to be higher than the upper surface of the substrate 1. Reference numeral 9 denotes a belt that supports and conveys the vicinity of the end surface of the substrate 1. Reference numeral 10 denotes a rail guide for guiding the substrate 1 by the belt 9, reference numeral 11 denotes a reel table for holding the rail guide 10, and reference numeral 12 denotes a roller fixed to the rail table. FIG. 3 is a perspective view of the substrate support. 13 is a stopper for stopping the substrate 1 conveyed by the belt 9, 14
Is a substrate detection sensor fixed to the stopper 13.

The operation of the conventional through-hole printing apparatus configured as described above will be described below.

First, the support base 2 is at a position lower than the upper surface of the belt 9. The substrate 1 is guided by the rail guide 13 and transported on the upper surface of the belt 9. When the substrate 1 hits the stopper 13 and the sensor 14 detects that the substrate 1 has arrived, the belt 9 stops, and the support 2 rises to support the lower surface of the substrate 1. When the support 2 moves to the upper limit, the substrate 1 is fixed by the positioning device 8. In this state, the suction of the hollow portion of the support base 2 is started, the scraper 9 is raised and the squeegee 5 is lowered while the suction is being performed, and the squeegee 5 and the scraper 6 are moved while the screen plate 4 is pressed against the substrate 1 so that the front of the squeegee 5 The conductive paste 7 supplied to the substrate 1 is extruded in a predetermined pattern on the screen plate 4, and is drawn to the upper surface of the substrate 1. A small hole for a through hole is formed in a predetermined position on the substrate 1. Simultaneously with the printing on the upper surface, the conductive paste is sucked into the hole of the substrate by the negative pressure of the hollow portion of the support table 2. The conductor paste is also printed on the side walls of the holes. The squeegee 5 moves from the end of the substrate 1 to the opposite end. Thereafter, the squeegee 5 is raised, the screen plate 4 is separated from the substrate 1, and the suction of the hollow portion of the support 2 is stopped. Next, the scraper 6 is lowered, and the scraper 6 and the squeegee 5 are returned to their original positions. At this time, the conductive paste 7 is applied almost uniformly on the screen plate 4 by the scraper 6. The support 2 and the stopper 13 descend from the upper surface of the belt 9, and the substrate 1 is put on the upper surface of the belt 9 and is carried out by the belt 9. When the printing on one side of the substrate 1 is completed, the cadmium plate 4 is replaced with a pattern on the opposite side of the substrate 1, and the substrate 1 on which one side is printed is supplied by the belt 9 with the printed side down. The opposite side is printed in the same procedure as the one-sided printing described above. FIG. 4 shows the printing order of through holes. FIG. 4 is an enlarged sectional view of a hole portion of the substrate 1.
In step a, first, a conductor paste is printed on one surface of the substrate 1. In step b, the conductive paste 7 penetrates deeply into the hole by suction from below and adheres to the side wall of the hole. Next, in step c, the substrate is inverted. Then, in step d, the opposite side is printed. The conductive paste overlaps on the side wall of the hole, and the upper surface and the lower surface of the substrate 1 are electrically connected to form a through-hole conductor.

However, in the above-described conventional configuration, as shown in FIG. 5, when the applied conductive paste is sucked, a part of the conductive paste becomes droplets in the through-hole, and the inside of the through-hole is reduced. The application state of the conductor paste may become non-uniform.

In order to prevent a sufficient amount of conductive paste from being sucked into the through-hole holes and to prevent insufficient penetration and poor conduction, a negative pressure is applied to the inside of the support base 2 until the hole is clogged even after printing with the squeegee. It is necessary to keep. For this reason, printing of the next board | substrate cannot be started immediately after completion | finish of printing, and there existed a problem that productivity was low.

Means for Solving the Problems In order to solve the above problems, the present invention provides a printing stage that applies a conductive paste to a substrate and sucks the substrate, and a vacuum pump that sucks the substrate sent from the printing stage again. A communication support is provided.

According to the present invention, since the conductor paste is printed by the printing stage and the sucked substrate is temporarily stopped and sucked again, the conductor paste can be evenly applied to the through-holes. The suction of the substrate is performed by the printing stage and another support table, so that the substrate can be suctioned for a long time without reducing the production number, and the conductive paste can be sufficiently drawn into the holes.

Embodiment FIG. 4 is a perspective view of a substrate supporting portion of a through-hole printing apparatus and a suction device in a later process according to an embodiment of the present invention.
In FIG. 4, 2 is a support stand, 3 is a hose, 9 is a belt, 10 is a rail guide, 11 is a rail stand, 12 is a roller,
13 is a stopper, 14 is a sensor, and the above is the same as the conventional configuration. Reference numeral 15 denotes a hollow support base that supports the lower surface of the substrate 1 and can move up and down. Reference numeral 16 denotes a hose that connects the vacuum pump 24 and the support base 15 to suck the hollow part of the support base 15. Reference numeral 17 denotes a belt arranged at the same height and width as the belt 9, reference numeral 18 denotes a rail guide for guiding the substrate 1 when the substrate 1 is conveyed on the upper side of the belt 17, reference numeral 19 denotes a rail base for holding the rail guide 18, reference numeral 20 Is a roller fixed to the rail base. Reference numeral 21 denotes a cylinder serving as a stopper for stopping the substrate 1 conveyed by the belt 17, and 22 denotes a cylinder 21.
And 23, a sensor for detecting that the substrate 1 has arrived.

The operation of the through-hole printing apparatus according to the present embodiment configured as described above will be described below.

In FIG. 1, the substrate 1 is transported from left to right. First, the support base 2 is at a position lower than the upper surface of the belt 9. The substrate 1 is guided by the rail guide 13 and transported on the upper surface of the belt 9. The substrate 1 hits the stopper 13 and the sensor
When the arrival of the substrate 1 is detected by 14, the belt 9 stops, and the support base 2 rises to support the lower surface of the substrate 1. When the support 2 moves to the upper limit, the substrate 1 is moved to the positioning device 8.
Is fixed by Start suction of the hollow part of the support base 2,
The squeegee and the scraper 6 are moved while the scraper 6 is raised and the squeegee 5 is lowered while the suction is being performed, and the screen paste 4 is pressed against the substrate 1. It is extruded in a pattern and printed on the upper surface of the substrate 1. Substrate 1
Are provided with small holes for three holes at predetermined positions. At the same time, the conductor paste is printed on the upper surface of the substrate 1 and at the same time, the conductor in the hole of the substrate 1 is formed by the negative pressure of the hollow portion of the support 2. The paste is sucked in, and the conductive paste adheres to the side walls of the holes. At this time, a part of the conductive paste attached to the side surface of the through hole may be in a droplet form as shown in FIG. 5 due to the air flowing through the through hole. The squeegee 5 moves from the end of the substrate 1 to the opposite end. Thereafter, the squeegee 5 is raised, the screen plate 4 is separated from the substrate 1, and the suction of the hollow portion of the support 2 is stopped. Then, the flow of the air in the through-hole is stopped, so that the portion of the conductive paste that has been dropped becomes flat due to surface tension. Next, the support 2 and the stopper 13 descend from the upper surface of the belt 9, and the substrate 1 is placed on the upper surface of the belt 9, carried out by the belt 9, and supplied to the upper surface of the belt 17. At the same time, the scraper 6 is lowered, and the scraper 6 and the squeegee 5 are returned to their original positions. At this time, the conductive paste 7 is applied almost uniformly on the screen plate 4 by the scraper 6. Next, the unloaded substrate 1 is placed on the upper surface of the belt 17 and
Is transported. At this time, the support base 15 is at a position lower than the upper surface of the belt 17. When the sensor 23 detects that the substrate 1 has reached the tip of the cylinder 21, the belt 17 stops, and the support 15 rises to support the lower surface of the substrate 1. When the support 15 moves to the upper limit, suction of the hollow portion of the support 15 is started, and suction is performed for a certain time. At this time, the paste attached to the inner wall of the hole of the substrate 1 is drawn into the lower surface of the substrate. Since the droplet portion of the conductive paste formed by the suction of the printing stage is flat, the conductive paste is uniformly applied in the through-hole hole by the re-suction. When the suction is completed, the support base 15 descends to a position lower than the upper surface of the belt 17, and simultaneously pulls the rod of the cylinder 21. The substrate 1 rests on the upper surface of the belt 17,
Is carried out by The above steps are automatically repeated one after another to perform through-hole printing. The substrate 1 on which printing on one side has been completed is printed on the opposite side by the present apparatus in the same manner as described above. Thereby, the conductive paste of the substrate 1 is conducted through the conductive paste attached to the inner wall of the hole.

As described above, according to the present embodiment, since the substrate sucked by the printing stage is sucked again, the conductor paste can be evenly applied in the through-hole, and the conductor paste can be applied in the through-hole hole. High-quality through-hole printing can be performed in a short time by eliminating hole clogging and insufficient pull-in.

Effect of the Invention As described above, the present invention provides a printing stage for applying a conductive paste to a substrate and sucking the substrate, and providing a support base connected to a vacuum pump so as to suck the substrate sent from the printing stage again. This makes it possible to apply the conductive paste evenly in the through-holes, and furthermore, it is possible to suction the substrate for a long time without increasing the time required for manufacturing, and the conductive paste which is a cause of poor conduction in the printing of the through-holes And high quality through-hole printing can be performed by eliminating clogging and insufficient pull-in in the through-hole.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of a through-hole printing apparatus of the present invention, FIG. 2 is a cross-sectional view of a conventional through-hole printing apparatus,
FIG. 3 is a perspective view of the substrate supporting portion, FIG. 4 is an enlarged sectional view of the substrate in a manufacturing process, and FIG. 5 is an enlarged perspective view of the same. DESCRIPTION OF SYMBOLS 1 ... Board | substrate 2, ... Support base 3 ... Hose 4, Screen board 5 ... Squeegee, 6 ... Scraper 7 ... Conductor paste 8 ... Board positioning device, 9 ... Belt 10 ... Rail guide , 11… Rail base 12… Roller, 13… Stopper 14… Sensor, 15… Support base 16… Hose, 17… Belt 18… Rail guide, 19… Rail base 20… Roller, 21 …… Cylinder 22 …… Fixed base, 23 …… Sensor 24 …… Vacuum pump

Claims (1)

(57) [Claims] 1. A first support table on which a substrate is placed while being communicated with a vacuum pump with an upper part opened, a substrate transfer belt provided along both side surfaces of the support table, and a substrate transferred by the substrate transfer belt. A printing stage having a guide for guiding a substrate to be transferred, and a second support stage that communicates with a vacuum pump when the upper side is open, and sucks the substrate transported by the substrate transfer belt from the first support stage. Through-hole printing apparatus.