JPH0361538A - Paste feeder for printing of screen printer - Google Patents

Abstract

PURPOSE:To feed paste for printing having high viscosity successively onto a screen easily and stably by pushing out and supplying printing paste onto the screen by turning a spiral screw. CONSTITUTION:When the quantity of printing paste on a screen is reduced and printing only by a certain number is completed, printing paste 12 in a housing section 9 is pushed out, discharged from a nozzle 10 and fed additionally onto the screen when a spiral screw 14 is rotated by a motor 15 for extrusion. When load to the spiral screw 14 is detected by a detecting section 18 as a revolving torque value at that time and the value is converted into a paste viscosity value and displayed to a viscometer 19, the paste viscosity value during printing can be determined. When the viscosity value is made larger than a desired value, a motor 23 for agitation is turned by the signal of the viscometer 19, and an agitating blade 20 is revolved, thus reducing viscosity due to the agitation of the printing paste 12 with the rotation of the agitating blade 20.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for feeding printing paste onto the screen of a screen printing machine.

Conventional technology In recent years, screen printing machines have been used in electronic circuit forming processes, etc., and in order to cope with mass production, they are fully automatic equipment that supplies the printing material to the bottom of the screen, prints, and discharges it to the next process. is widespread. Recently, for example, in the 1980s,
A device for automatically additionally supplying printing paste, as described in Japanese Patent No. 126891, has begun to be put into practical use.

FIG. 2 shows a conventional method for supplying printing paste to a screen printing machine. In Fig. 2, 1 is the printing paste on the screen 2, 3 is the syringe or cartridge that houses this printing paste 1, 4 is the nozzle at the bottom, 5 is the air hose, 6 is the screen frame, 7 8 is a printing squeegee, and 8 is a scraper. The printing paste 1 is supplied onto the screen 2 from the nozzle 4 by sending compressed air from the air hose 6 to the syringe or cartridge 3.

Problems to be Solved by the Invention However, the above configuration works well when the viscosity of the printing paste is relatively small and soft, but when printing cream solder on a printed circuit board, for example, the viscosity is 300 Since a very large poise of 6000 poise is used, cream solder often does not come out from the nozzle 4 even if compressed air of about 5 kti/af is sent, which has the problem that it is not practical.

In view of the above problems, the present invention provides a printing paste supply device for a screen printing machine that can easily and stably supply printing paste onto a screen even when the printing paste has a high viscosity.

Means for Solving the Problems In order to solve the above-mentioned problems, the printing paste supply device for a screen printing machine of the present invention has a printing paste storage section disposed above the screen, and a spiral screw is installed in the storage section. It has a structure in which printing paste is extruded and supplied onto the screen by rotating a spiral screw.

Function: With the above-described configuration, the printing paste is extruded by the rotation of the spiral screw, so that printing paste with high viscosity can be easily and stably supplied onto the screen from the storage section.

EXAMPLE Hereinafter, a printing paste supply device for a screen printing machine according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of the main parts of a printing paste supply device for a screen printing machine according to an embodiment of the present invention. 9 has a nozzle 10 formed at the lower end and an opening 11 at the upper end,
This is a storage section that stores printing paste 12 inside. 1
3 is a lid provided on the opening. 14 is a spiral screw, one end of which is connected to an extrusion motor 15 that rotates this spiral screw, a pulley 16, and a belt 17.
are connected via. Furthermore, spiral screw 1
4 is provided with a detection section 18 that detects the rotational torque. Reference numeral 19 is a viscometer that can convert the rotational torque value detected in one day into a paste viscosity value and display it, as well as output an electric signal if the detected viscosity value is larger than the desired viscosity value. . 2o is a stirring blade which is provided above the spiral screw 14 so as to be rotatable independently of the spiral screw 14, and is connected to a stirring motor 23 by a pulley 21 and a belt 22.

When the amount of printing paste on the screen decreases and a certain number of sheets have been printed, when the spiral screw 14 is rotated by the extrusion motor 15, the printing paste 12 in the storage section 9 is extruded and discharged through the nozzle 10. and then additionally supplied on the screen. At this time, if the load on the spiral screw 14 is detected as a rotational torque value by the detection unit 18, and the value is converted to a paste viscosity value and displayed on the viscometer 19, the paste viscosity value during printing can be known.

Furthermore, if this viscosity value becomes larger than the desired value,
The stirring motor 23 is rotated by the signal from the viscometer 19 described above, and the printing paste 1 is rotated by rotating the stirring blade 20.
2 can be kneaded to reduce the viscosity.

Effects of the Invention As described above, the present invention provides a printing paste storage section above the screen, a spiral screw provided in the storage section, and extrusion and supply of printing paste onto the screen by rotating the spiral screw. Therefore, high viscosity printing paste can be easily and stably supplied onto the screen one after another.

[Brief explanation of drawings]

FIG. 1 is a block diagram of main parts of a printing paste supply device for a screen printing machine according to an embodiment of the present invention, and FIG. 2 is a front view of a conventional printing paste supply device for a screen printing machine.

Claims (3)

[Claims] (1) A printing paste storage section provided at the top of the screen, a spiral screw provided in the storage section, and a first drive section that rotates the spiral screw; A printing paste supply device for a screen printing machine, characterized in that the printing paste is extruded from a storage section and supplied onto a screen. (2) For printing with a screen printing machine according to claim 1, which is provided with a stirring blade in the paste storage section and above the spiral screw, and a second drive unit that rotates the stirring blade. Paste supply device. (3) a detection unit that detects the rotational torque value of the spiral screw between the spiral screw and the first drive unit;
Claim 1, further comprising a viscometer that converts and displays the rotational torque value into a paste viscosity value and outputs an electric signal to the second drive unit when the detected viscosity value is larger than the desired viscosity value. Alternatively, the printing paste supply device for a screen printing machine according to item 2.