JPH01192556A - Screen printing machine - Google Patents

Abstract

PURPOSE:To prevent viscosity from varying due to blind printing or excess feed, by a method wherein a sensor for detecting a position along a screen of a squeegee is established, and a controller for actuating a feeder which feeds a printing material in relation to this sensor is established. CONSTITUTION:When a first squeegee 15a comes in contact with a screen 3, a transfer material 7 starts to transfer, and the first squeegee 15a slides to right end. Thereby, a printing material 19 is pushed out through a hole 6 of the screen 3 and is printed on a matter to be printed 2. Then, when the transfer material 7 transfers to the other end of the screen 3, a switch 31 is actuated, and the output signal is given to a controller 25. At that time, the first squeegee 15 is lifted from the screen 3, and the matter to be printed 2 is exchanged. A second squeegee 15b is lowered onto the screen 3, and is slid from the other end to one end thereof. In this process, the printing material 19 is printed on the matter to be printed 2 through the screen 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a printing material having a relatively high viscosity, and relates to contact with a screen printed on a paulownia body, and when soldering an electronic component 2 onto a printed circuit board, a solder paste is applied. v′i I/c printed on the printed circuit board
Applied.

[Prior art]

Previously, VC S touched the screen in this building? With a printing material, such as a conductive solder paste, applied to the screen, the printing material is passed through the screen and the cover located below it by sliding a squeegee back and forth on the screen. Printed materials such as printed circuit boards.

However, the remaining amount of the printing material had to be measured visually and then fed manually.

[The point to be solved by this invention] This manual supply of printing materials (if the number of printed sheets is large, VC k
Diagonal cuts occur in the work material. This material shortage is related to the number of sheets printed at one time, the printing area, etc., and it is difficult to know exactly when it will occur. Preliminary. It is difficult to measure, and when it occurs, printing becomes blurred or blank printing occurs. For this reason, people have to frequently monitor the remaining amount and are worried about running out of material, so there is a tendency to supply more than necessary. This not only causes printing material to accumulate around the edges of the screen and on the squeegee, making cleaning time-consuming, but also changes the viscosity of some printing materials, making them unsuitable for use. If this occurs, the printing material must be disposed of.

[Purpose of the invention]

The purpose of this invention is to improve the manual feeding of printing materials and automatically feed the minimum necessary amount mechanically, thereby preventing blurred printing, empty printing, or changes in viscosity due to overfeeding as much as possible. do.

[Summary of the invention]

In order to achieve the object, this invention is provided with a sensor that detects the position of the squeegee along the screen.
A controller is provided in conjunction with the sensor for operating a feeding device for feeding printing material.

[Action of the invention]

The sliding position of the squeegee on the screen is detected by the sensor, and the squeegee operates the scouring controller in the appropriate position to feed the printing material from the feeding device onto the screen, thereby removing the printing material. This prevents the supply from running out and prevents blurred printing and blank printing.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

That is, what is shown in FIGS. 1 to 4 shows a double squeegee system, in which a printing medium such as a printed circuit board is placed on a printing stage 1. Furthermore, a screen 3 is disposed above the printing material along the surface of the stage l. As shown in FIG. 6, the screen is composed of a thin plate 4 having a number of holes 6 and a frame 5 reinforcing the thin plate at its periphery. Also, on the screen 3 is a moving body 7 that moves reciprocatingly along this screen within a range of a certain distance from the screen 3.
will be placed. This mobile body has a pair of cylinders 1
) That is, the first cylinder 1)a and the second cylinder 1)b are provided at a predetermined distance from each other in the moving direction of the moving body 7. These cylinders are air cylinders composed of a cylindrical body 12 and a piston 13 supported by the cylindrical body so as to be movable in both directions. A holder 14 is fixed to the lower end of each piston 13, 13, and square rod-shaped squeegees 15, that is, a first squeegee 15a and a second squeegee 15b are attached to this holder. Note that this nukiji is arranged so that its fine line intersects at right angles to the '5iIJJ direction of the moving body 7, that is, the cylinder 1).

The printing material 19 has a predetermined viscosity, and is, for example, a conductive solder paste.

This printing material is fed onto the screen 3 by a material feeder 21. Furthermore, the material feeder 21 is connected via a feed pipe 22 to a supply source (not shown). This material feeder is fixed to the movable body 7 by a plate 23. A controller 25 is provided between the material supply machine 21 and the supply source. This controller is connected to the supply pipe 22
A flow controller 27 having a solenoid valve 26 and a filter, a timer relay 2 that controls the solenoid valve 26
9 and a preset counter 30.

The moving body 7 has a switch 31, that is, a first optical switch 31a, and a second optical switch 31a is located on the optical axis of the tenth photoelectric switch at a position spaced apart from the first photoelectric switch.
The photoelectric switches 31b are each fixed, and the first photoelectric switch 31a is fixed! The second photoelectric switch 31b emits an output when it approaches the optical '1 switch 31bK of @2 by a predetermined distance, and when a projection type photoelectric switch is used, this switch is a pair of photoelectric switches. It consists of
In the case of a reflective type, it consists of one photoelectric switch.

Further, this switch is not limited to an optical tortoise switch, but may be constructed from a proximity switch or a limit switch. An output device [32] is provided at the output end of the switch 31, thereby forming a sensor 33. This output device is connected to controller 25.

Next, the operation of the above configuration will be explained with reference to the timing chart shown in FIG.

First, to start the contact, place the substrate 2 on stage 1.
A predetermined amount of printing material 19 is supplied onto the screen 3 with the upper Vc placed thereon. This initial supply can be supplied by the beginning of contact. That is, at the time of starting, the squeegees 15a and 15b are also separated from the screen 3, and in this state, the movable body 7 starts reciprocating movement along the screen 3 within a distance range. Then, when the first photoelectric switch 31a approaches the second photoelectric switch 3lb IC, for example twice, that is, when the moving body 7 moves to the right VC 12 times in the figure, the controller 25 A signal (Fig. 5A) is issued, which activates the timer relay 29, and the solenoid valve 26 does not operate within the set time range (Fig. 5C).
), the printing material 19 is fed onto the screen 3 from the material feeder 21 . Then, the moving body 7 is moved to the left end and becomes the state shown in FIG. In this state, cylinder 1) is driven,
When the first piston 13a descends and the first squeegee 15a contacts the screen 3 as shown in FIG. 2, the moving body 7 starts moving. At the same time, the first squeegee-15a
The kl screen 3 is slid from one end, ie, the left end, to the other end, ie, the right end, whereby the printing material 19 is extruded through the holes 6 of the screen 3 and printed onto the substrate 2. When the moving body 7 moves to the other end of the screen 3, the switch 31 is activated and the output signal is sent to the controller.
The set value of the preset counter 30, for example 2, is decremented by one, and the value is set to 1. At this time, the first squeegee 15a is lifted from the screen 3 as shown in FIG. 3, and printing is completed. Here, the printing material 2 is also taken out from the stage 1 or moved by a conveyor or the like, and the printing material 2 to be printed next is placed on the stage l.

In this state, a second squeegee 15b is lowered onto the screen 3 in place of the first squeegee 15a, as shown in FIG. 4, and then slid from the other end of the screen 3 to one end thereof. As a result, the screen 3 as well as the printing material sent to the edge are pushed back towards one end of the screen 3. In this process, the printing material 19 is printed onto the substrate 2 through the screen 3, completing the printing of the second substrate. Then, this printing material is removed and the next printing material that requires further printing is moved below the screen 3.

Thereafter, the next printing material 2 is taken out in the same manner, the next printing material is set, and printed by the first squeegee 15a, but when this squeegee reaches the right end of the screen 3, the switch 31 is activated. The output allows you to preset and
The counter 30 further subtracts the set value to become O. The solenoid solenoid valve 26 is opened and printing material is fed from the supply source through the material feeder 21 onto the screen 3 at a pressure set by the flow controller 27 for a time set by the timer relay 29.

At this time, the printing material 2 is replaced with an unprinted material, and printing is performed using the second squeegee 15b.

In other words, the supply of printing material 19 takes place only when switch 31 is actuated the number of times set in preset counter 30.

In FIG. 5, E indicates the timing of supply of the printing material 2.

In the above explanation, the operation was explained for the double squeegee type, but the same operation can be performed for the single squeegee type. That is, among the single squeegee type, the one-scraper type prints in one direction using one squeegee 15, as shown in FIG. In the same figure, the squeegee 15 is indicated by arrow a.
The squeegee 15 is slid from one end of the screen 3 to the other end while being in contact with the screen 3 (arrow b), thereby removing the printing material 1 on the screen 3.
9 onto the printing material 2 through the screen 3. At the other end of the screen 3, the squeegee 15 is lifted from the screen 3 (arrow C), and the scraper 41 is lowered onto the screen 3 (arrow d). , in this state, slide the screen 3 from the other end toward its one end (arrow e), and return the excess printing material 19 sent to the other end of the screen 3 to one end of the screen 3, that is, its original position, and return it here. The squeegee 15 is lifted up (arrow f).

Also, among the single squeegee types, the jumping type is used to slide the squeegee 15 from one end of the screen 3 toward the other end (arrow a) as shown in FIG. This is the device that performs printing. Lift the squeegee 15 near the other end of the screen 3 (arrow b
), this is further moved to the other end of the screen 3, that is, it is brought into contact with the screen 3 again in a state where it has jumped over the remaining printing material 19 sent to the other end of the screen 3, and in this state, the first Replace the second printing material with the second printing material, and slide the squeegee 15 from the other end of the screen 3 toward one end of the screen 3 in the opposite direction as shown by the dashed arrow C. Print. The squeegee 15 is then lifted near one end of the screen 3 and further moved to one end of the screen 3 (dotted arrow d), that is, to straddle the remaining printing material that has been returned to its original position.

Even in these single squeegee types, the squeegee
15 has been moved the number of times set by preset counter 30, material feeder 21 can be activated to automatically feed printing material onto screen 3.

The material feeder 21 has a plurality of feeders 21a and 21b held on a holding plate 35 as shown in FIG.

It may be moved in the b direction.

Further, as shown in FIG. 10, the material feeder 21 is attached to the square cylinder 37, and this is indicated by the arrow a.

It can also be moved back and forth in the b direction.

Furthermore, as shown in Figure 1), it is also possible to attach the material feeder 21 to a knock cylinder 38, and this knock cylinder to further attach it to a rodless cylinder 39, and move these in the directions of arrows a, b and arrow C9d, respectively. .

〔Effect of the invention〕

As described above, the present invention includes a sensor that detects the position of the squeegee along the squeegee, and a controller that operates the workpiece supply device in association with the sensor.
Since there is no need for manual replenishment, there is no risk of running out of materials, and there is no need for constant monitoring.
Furthermore, since the material is not supplied in excess of what is necessary, there is little change in the viscosity of the material, and there is little deterioration such as oxidation (therefore, there is little material to be wasted).

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the screen contacting device according to the present invention, FIGS. 2, 3, and 4 are front views explaining the operation of the device shown in FIG. 1, and FIG. Timing chart for operation; Figure 6 is a partially cutaway plan view showing contact with the screen; Figure 7 is an explanatory diagram showing the scraper type in the single squeegee type; Figure 8 is the single squeegee type. 9, 10, and 1) are front views showing modified examples of the material feeder. l...stage, 2...printing material, 3...screen, 4...thin plate, 5...frame, 6...hole, 7...
- Moving body, 1)... Cylinder, 12... Cylindrical body, 1
3... Piston, 14... Holder, 15... Squeegee-1) 9... Printing material, 21... Material feeder, 22... Supply pipe, 23... Mounting on plate, 25...
Controller, 26... Solenoid valve, 27... Flow rate controller, 29... Timer relay, 30... Preset counter, 31... Switch, 32... Output device, 33... ... Sensor, 35 ... Holding plate, 36
... Jig cylinder, 37... Square cylinder. 38...Knock cylinder, 39...Rodless cylinder. Patent applicant: Newel Co., Ltd.
(2 people) Figure 5 Figure 6 Figure 7 Figure 7

Claims (4)

[Claims] (1) A cylinder supported movably along the screen, a squeegee held by the cylinder, and a supply device for supplying printing material onto the screen, the supply device supplying the printing material onto the screen. a sensor for detecting the position of the squeegee along the screen, and activating the feeding device in conjunction with the sensor; Screen printing device equipped with a controller (2) The cylinder is composed of a first cylinder and a second cylinder, and is fixed to a moving body that moves along the screen, and the squeegee is attached to the first and second cylinders, respectively. Consisting of a first squeegee and a second squeegee, the first squeegee
With the first squeegee in contact with the screen by a cylinder, the movable body is moved from one end of the screen in a first direction, and the second squeegee is brought into contact with the screen. Claim 1, comprising a double squeegee system in which the movable body is moved along the screen from the other end in a second direction opposite to the first direction while the movable body is in contact with the top of the screen.
Screen printing device as described in Section. (3) A squeegee that slides on the screen and a scraper that moves the printing material on the screen are installed in parallel with the squeegee, and these are held movably up and down, and the cylinder is used to move the printing material on the screen. With the squeegee in contact with the screen, the squeegee is moved from one end of the screen to the other, the squeegee forces printing material through the screen, and the squeegee is moved from one end of the screen to the other end of the screen. Raised relative to the screen and with the scraper in contact with the screen, the scraper is moved along with the squeegee from the other end of the screen to one end thereof, thereby removing excess printing material from the screen. 2. The screen printing apparatus according to claim 1, which is constructed using a single squeegee scraper method that returns one end of the screen. (4) A squeegee that slides on the screen and a scraper that moves the printing material on the screen are installed in parallel with the squeegee, and these are held movably up and down, and the cylinder is used to move the printing material on the screen. With the squeegee in contact with the screen, the squeegee is moved from one end of the screen to the other, the squeegee forces printing material through the screen, and the squeegee is moved from one end of the screen to the other end of the screen. The squeegee is raised relative to the screen, and the squeegee is moved to the other end of the screen, and the scraper is brought into contact with the screen, and the scraper is moved together with the squeegee from the other end of the screen to one end thereof. 2. The screen printing apparatus according to claim 1, wherein said screen printing apparatus is constructed by a single squeegee jumping method in which excess printing material is returned to one end of said screen.