JPS60259447A - Negative pressure suction mechanism of printing table in screen printing machine - Google Patents

Abstract

PURPOSE:To achieve a reliable processing without changing a printing table by providing on a surface of the printing table plural concave hollows which communicate with a negative pressure suction device and by providing negative pressure suction perforations in eccentric positions and the covers that are shaped similarly to the shapes of the hollows to be fixed in such a manner as to be able to revolve. CONSTITUTION:Plural concave hollows 2 which communicate with a negative pressure suction device through vent holes are provided on a printing table 1. Each concave hollow 2 is provided with a round cover 9 which has a shape like the hollow 2 to be fit in such a manner as to be able to rotate. A secondary round concave hollow 10 which communicates with a vent hole 3 is provided in a suitable position of the cover 9, and an eccentric, negative pressure suction hole 5' is perforated in the secondary hollow 10 and a secondary cover 9a which has the same shape as that of the secondary hollow 10 is fit in such a manner as to be able to rotate. Since the position on the printing table surface of the negative pressure suction hole can easily be changed to a desirable position, a handling of objects to be printed with different sizes or objects with perforations may be performed easily and in a sure method on the same printing table.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a negative pressure suction structure of a printing table in a screen printing machine that prints by fixing a printing material to a printing table using negative suction force.

Conventionally, in screen printing machines that print circuit patterns on printed circuit boards, the printed circuit board, which is the object to be printed, is positioned and fixed on a printing table and printed. Fixation on the table is usually done by negative pressure suction means.

However, the effect of this negative pressure suction means varies greatly depending on the arrangement structure of the negative pressure suction holes drilled in the printing table. This tendency is noticeable in substrate processing. In other words, the negative pressure suction holes in the printing table must always be positioned to avoid perforations in the substrate, which is the object to be printed, and if such consideration is not taken, the effect of suctioning and fixing the substrate to the printing table will be high. This is because it will not be possible.

1; Adjust the negative pressure suction hole on the surface of the printing table to the size of the substrate.
. Difference, perforation. Yes or no.
. . Various ideas have been proposed so far for
Although some devices have demonstrated some effectiveness, the invention disclosed herein is extremely easy to process and handle, and greatly expands the range of arbitrariness in setting the position of the negative pressure suction hole. It can be said that it is superior to the conventional one.

Hereinafter, the structure of the present invention will be explained in detail based on its embodiments.

A circular recess 2 is provided on the surface of a printing table 1 on which a printed circuit board, which is a printing medium M, is placed. Therefore, this circular recess 2 has a ventilation hole 3 bored in its bottom surface.
through which it communicates with a negative pressure suction device (not shown). A lid body 4 having the same shape as the circular recess 2 and having a negative pressure suction hole 5 bored at an eccentric position is rotatably fitted into the circular recess 2 . The reason why the concave portion 2 is circular and the lid body 4 is specified to have the same shape is to ensure omnidirectional rotation of the lid body 4 and to make the rotation movement smoother.

It is necessary to provide a plurality of circular recesses 2 on the surface of the printing table 1, and the positions thereof are preferably selected so as to cover the four corners and the center of the printing table 1.

Further, it is important that the negative pressure suction holes 5 formed in the lid body 4 are bored at eccentric positions in each lid body 4.
Not all negative pressure suction holes 5 must be located at a certain distance from the center of the lid 4, but rather the positions of the negative pressure suction holes 5 should be set eccentrically to meet various demands. It is preferable that the positions are different.

P shown in the figure is an O-ring-shaped backing member installed between the lid body 4 and the recessed part 2 of the printing table 1,
By interposing this backing member P, there is an advantage that dimensional control for maintaining airtightness between the inner wall of the circular recess 2 and the outer wall of the lid body 4 becomes easier.

Further, numeral 6 indicates a notch portion formed in the lid body 4 for accommodating the backing member P. Note that the means for rotating the lid 4 may be any suitable means. For example, a plurality of engaging portions may be formed on the surface of the lid 4, and a hook may be engaged with the engaging portions. They may be combined into one line.

Furthermore, C in the figure is a belt conveyor for carrying the printing material M onto the printing table i, and 7 is a weight member that opens and closes the ventilation hole 8 communicating with the negative pressure suction device. The contact surface 7a, which has a diameter larger than that of the vent hole 3, is brought into contact with and separated from the surface of the vent hole 8 to open and close the vent hole 3. During the rotation process of the lid body 4, the weight member 7 is always positioned so as to face the ventilation hole 8 and is loosely fitted into the accommodation portion 8 of the lid body 4, so that the weight member 7 is placed above the ventilation hole 3. The weight member 7 uses its own weight to ensure that the contact surface 7a closes the ventilation hole 8. Therefore, if such a structure is adopted, it becomes easier to eliminate the need for the negative pressure suction hole 5 on the printing table 1 compared to other means. .

In addition, in the example shown in FIG. 4, an integral housing portion 8 that loosely accommodates the weight member 7 is penetrated to the surface of the printing table 1, and a contact surface 7a of the weight member 7 is provided with a hole having a diameter smaller than the diameter of the ventilation hole 3. A falling portion 7b is formed therein. With this structure, when the contact surface 7a of the weight member 7 comes into contact with the ventilation hole 3, the weight member 7 is lower than the surface of the printing table 1 by the length of the falling part 7a', so that the weight member 7 There is an advantage that the state in which the vent hole 3 is blocked can be visually observed from the surface of the printing table 1.

Now, as for the negative pressure suction structure on the surface of the printing table 1, in addition to the structure described above, structures as shown in FIGS. 5 to 7 can be considered. The second lid 9a has a second recess 10 formed in the rotating lid 9, and a negative pressure suction hole 5' bored in the second recess 10 at an eccentric position. According to this structure, the negative pressure suction hole 5' bored at an eccentric position of one lid 9a absorbs the negative pressure by rotating the two lids 9.9a. This makes it possible to significantly widen the displacement width of the suction hole 5', and this is a remarkable effect when dealing with printing materials having perforations, such as so-called industrial substrates.

The invention related to this structure will be explained in more detail below.

A plurality of circular recesses 2 are provided on the surface of the printing table 1 and communicate with a negative pressure suction device (not shown) through ventilation holes 3. The lid body 9 is rotatably fitted. The lid 9 is also provided with a second circular recess 10 that communicates with the ventilation hole 8 at an appropriate position, and this second recess 10 has a negative pressure suction hole 5 at an eccentric position. A second lid body 9a having the same shape as the first recessed portion 10 is rotatably fitted therein.

Pa and Pb in the figure are the notches 6a1 of the two lids 9.9a.
An O-ring shaped backing member housed in 6b,
Its operation and effects are the same as those of the structures shown in FIGS. 5 to 7.

Further, 7' in the figure is a weight member loosely fitted into the housing part 8' of the lid body 9a, and the contact surface 7 has a diameter larger than the diameter of the ventilation hole 3.
a/ comes into contact with and separates from the surface of the ventilation hole 3 to open and close the ventilation hole 3, and also penetrates the housing portion 8' to the surface of the printing table 1, and furthermore, the contact surface 7'a' of the weight member 7'
) is advantageous in that the opening and closing of the ventilation hole 3 can be visually observed from the surface of the printing table 1 by forming a falling part with a smaller diameter than the diameter of the ventilation hole 8.

Regarding the means for rotating the lid body 9.9a in this example, it goes without saying that any suitable means may be employed. For example, a plurality of engaging portions may be provided on the surface of the lid body 9.9a. Similarly to the structure described above, the hook may be formed and rotated by engaging the hook with the engaging portion.

The present invention is constructed as described above, and the position of the negative pressure suction hole on the printing table surface can be easily moved to a desired position at any time, so that the size of the negative pressure suction hole can be different. All printing materials and perforated materials can now be handled more easily and reliably on the same printing table.

[Brief explanation of drawings]

Fig. 1 is a partially omitted top view of a printing table embodying the present invention, Fig. 2 is a partially omitted side sectional view of the printing table relating to the main parts of the present invention, and Figs. A detailed explanation of the present invention having a pore opening/closing member, FIG. 4 is an explanatory diagram of an improved example of FIG. 3, and FIG. 5 is an enlarged explanatory diagram of main parts of another example of the present invention. 6 is a top view of FIG. 5, and FIG. 7 is a partially omitted side sectional view illustrating the structure of the example of FIG. 5 having a vent opening/closing member. l...Printing table 2.10...Circular recess, 3...Vent hole 4, 9.9
a... Lid body 7. 7'... Weight member 7 a + 7 a'... Contact surface, 7b. Falling part 8.
8'...Shakuhachi patent application for weight member storage part ■Ω...Komanen Aoi υ Reisha

Claims (4)

[Claims] (1) In a printing table of a screen printing machine that fixes the printing material to the surface thereof through negative pressure IJII holes, a circular recessed portion on the surface of the printing table 1 communicates with a negative pressure suction device through a ventilation hole 3. A negative pressure suction hole 5 is provided at an eccentric position in each of the recesses 2, and a plurality of recesses 2 are provided.
A negative pressure suction structure for a printing table in a screen printing machine, characterized in that a lid body 4 having the same shape as the above is rotatably fitted. (2) A plurality of circular recesses 2 are provided on the surface of the printing table 1 to communicate with the negative pressure suction device through ventilation holes 3, and a lid body 9 of the same shape as the recess 2 is attached to each of the recesses 2. A second circular recess 10 is formed in the lid 9 so as to be rotatable and communicates with the ventilation hole 3.
A screen printing machine characterized in that a negative pressure suction hole 5' is bored at an eccentric position in O, and a second lid body 9a having the same shape as the second recessed part 10 is rotatably fitted. Negative pressure suction structure of printing table. (3) A negative pressure suction hole 5 is provided at an eccentric position in the circular concave part 2 that communicates with the negative pressure suction device through the ventilation hole 3, and the lid body 4, which has the same shape as the concave part 2, can be rotated. A weight member 7 having a contact surface 7a having a diameter larger than the diameter of the ventilation hole 3 is inserted into the accommodation portion 8 of the lid 4 so that the contact surface 7a contacts the ventilation hole 3 during the rotation process of the lid 4. A negative pressure suction structure for a printing table in a screen printing machine, which is equipped with vent opening/closing members that are loosely fitted so as to face each other. (4) A patent claim characterized in that the weight member accommodating portion 8 of the lid body 4 is formed in a penetrating shape, and a falling portion 7b having a diameter smaller than the diameter of the ventilation hole 3 is provided on the contact surface 7a of the weight member 7. Negative pressure suction structure of the printing table according to item 3.