JPH05116274A - Screen printing machine - Google Patents

Abstract

PURPOSE:To provide a screen printing machine always properly keeping the temp. of the printing paste on a screen. CONSTITUTION:A screen printing machine has a means (not shown in a drawing) supplying an object 10 to be printed to a printing position, a means applying the object 10 to be printed supplied to the printing position of a squeezee 7 and a screen 8 and a means (not shown in the drawing) discharging the printed object 10. Further, the temp. sensor 15 arranged in the vicinity of the printing position and means sending air controlled in temp. to the periphery of the printing position by the feedback of the temp. in the vicinity of the printing position detected by the temp. sensor 15 such as a chamber 12, a duct 13, a louver 14 or an air conditioner are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fully automatic screen printing machine for printing conductor paste, cream solder or the like on a printed circuit board in an electronic circuit board mounting process.

[0002]

2. Description of the Related Art In recent years, electronic circuit boards have tended to be miniaturized and highly densified as their products have become lighter, thinner, shorter and smaller. Therefore, the screen printing machine is required to perform high-precision printing. Hereinafter, a conventional screen printing machine will be described with reference to the drawings. FIG. 3 is a perspective view of a conventional screen printing machine. The printing material supplied by the loader rail 1 is position-controlled by the printing material setting stage 2. Then, the printing material regulation stage 2 rises and the screen 3
The material to be printed below. Then, the squeegee 4 moves on the screen 3, and the printing paste 5 is pushed out from the punched hole of the screen 3 to the printing object. This completes the printing process, and the material to be printed is discharged to the next process by the unloader rail 6. FIG. 4 is a simplified diagram showing the printing process. Here, 7 is a squeegee, 8 is a screen, 9 is a printing paste, and 10 is an object to be printed, and printing is performed by the above operation.

[0003]

In such a conventional screen printing machine, the temperature of the printing paste on the screen depends on the environmental temperature of the place where the printing machine is installed. The viscosity of the printing paste generally changes with changes in temperature. The change in viscosity of the printing paste affects the printing state, causing bleeding and blurring.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a screen printing machine having means for keeping the temperature of the printing paste on the screen at an appropriate temperature suitable for printing.

[0005]

In order to achieve the above object, the screen printing machine of the present invention comprises means for supplying a printing material to a printing position, and means for screen printing the printing material supplied to the printing position. A means for discharging the printed substrate, and a temperature sensor installed near the printing position,
The temperature sensor detects the temperature near the printing position and feeds back the temperature-controlled air to the periphery of the printing position.

[0006]

With the above-described structure, the screen printing machine of the present invention controls the temperature of the atmosphere around the screen to maintain the temperature of the printing paste at a temperature suitable for printing.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. For simplification, only the portion where screen printing is performed is shown in the figure, and illustration and description of the means for supplying the printed material to the printing position and the means for ejecting the printed material before and after that are omitted. As shown in the figure, a chamber (air reservoir) 12 capable of adjusting the wind direction is provided on the ceiling of the main body cover 11. Duct 13 in chamber 12
Air whose temperature is controlled is supplied from the air conditioner 16 via the. The air is sent onto the screen from a louver 14 whose wind direction can be adjusted. The wind velocity is such a light wind that the printing paste on the screen does not dry (0.5m / s in the experiment with cream solder).
degree). Further, a temperature sensor 15 is provided on the screen near the printing paste, and the temperature on the screen is fed back to the air conditioner 16.

FIG. 2 is a perspective view of the screen printing section.
8 is a screen and 17 is a screen holder. A heater 18 is provided on the screen 8 and is connected to a temperature control unit 19 to keep the upper surface of the screen at a constant temperature. Of course, the heater 18 is an auxiliary one and is not always necessary in the case of the present invention.

[0009]

As is apparent from the above description, the screen printing machine of the present invention maintains the temperature of the printing paste on the screen at an appropriate temperature by controlling the temperature of the atmosphere on the screen or the upper surface of the screen. It provides excellent printing.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the configuration of a screen printing machine according to the present invention.

FIG. 2 is a perspective view showing a configuration of a screen printing machine according to the present invention.

FIG. 3 is a perspective view showing a configuration of a conventional screen printing machine.

FIG. 4 is a schematic diagram showing a configuration of a conventional screen printing machine.

[Explanation of symbols]

7 Squeegee (means for screen printing) 8 Screen (means for screen printing) 10 Object to be printed 12 Chamber (means for sending air whose temperature is controlled around the printing position) 13 Duct (air whose temperature is controlled around the printing position) 14 louver (means for sending temperature-controlled air around the printing position) 15 temperature sensor 16 air conditioner (means for sending temperature-controlled air around the printing position)

 ─────────────────────────────────────────────────── ─── Continued front page (72) Hiroyuki Miyake, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Akira Iizuka, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 1. A means for supplying a printing material to a printing position, a means for screen-printing the printing material supplied to the printing position, a means for discharging the printed printing material, and a means installed near the printing position. A screen printing machine provided with a temperature sensor and means for feeding air whose temperature is controlled around the printing position by feeding back the temperature near the printing position detected by the temperature sensor.