JPH0328079B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to a circuit forming apparatus that forms a predetermined circuit by discharging a liquid circuit forming material onto an electrical substrate material or the like.

[Prior Art] Conventionally, there is a device of this type as shown in FIG.

In the figure, reference numeral 1 denotes a moving table on which the substrate material 2 is placed, and it moves at a constant speed in the horizontal direction, that is, in the X and Y directions (indicated by arrows in the figure), by a predetermined drive device according to a predetermined circuit formation pattern. Move with. A nozzle 3 contains a liquid circuit forming material P (hereinafter referred to as paste) and has a minute discharge hole 3a at its tip. A tube 4 supplies compressed air into the nozzle 3 and is connected to a predetermined air pressure source via a solenoid valve serving as a pneumatic control valve. 7 has a nozzle holding part 7a, and by rotating the ball screw shaft 9, the rail 8 of the frame 8 is
It is an elevating body that ascends and descends in the vertical direction (Z direction) along a, and a ball nut 10 that is screwed into a ball screw shaft 9 is fixed to the upper surface. In addition, above 7~
10 constitutes a lifting mechanism A.

In the circuit forming apparatus described above, when discharging the paste P, the nozzle 3 is first positioned on the substrate material 2 at a predetermined interval. The position at which this nozzle 3 is set varies depending on the type of paste to be applied, the diameter of the discharge hole 3a of the nozzle 3, etc., but in order to obtain an appropriate discharge condition, the thickness of the paste P to be deposited must be It needs to be located at the top.
When the nozzle 3 is set, the solenoid valve is opened, compressed air is sent into the nozzle 3, and the paste P is discharged. At the same time, the moving table 1
moves according to a predetermined circuit pattern, and the paste P is adhered to the substrate material 2. In addition, in this apparatus, the paste P to be applied is mainly for conductors, insulators, resistors, etc. All of these are made by diffusing minute metal particles into a highly viscous solution, and after the paste P has been discharged, it is dried and fired at a high temperature of 800°C to 1000°C to obtain the desired electrical properties. It will be done. The substrate material 2 used is usually a so-called ceramic substrate made of 96% alumina (Al ₂ O ₃ ) or the like so that it can withstand the above-mentioned high temperatures.

[Problems to be Solved by the Invention] By the way, the air pressure within the nozzle 3 increases and decreases with a so-called first-order delay with respect to the opening/closing signal of the electromagnetic valve as shown in FIG. 7a. Therefore, the discharge flow rate of the paste P determined by the air pressure will draw curves as shown in A and B in FIG. 7B at the start and end of discharge. Therefore, when the paste P is discharged onto the substrate material 2 moving at a constant speed, the state of the discharge is such that the state of paste adhesion is uneven at the leading end _P1 and the terminal end _P2 of the pattern, as shown in FIG. 7c. become. That is, at the start of dispensing, the movable table 1 starts moving even though a sufficient dispensing amount cannot be obtained, so the tip of the formed pattern becomes thinner than the other parts, and the electromagnetic valve Due to the first-order delay after closing, the terminal end _P2 of the pattern becomes stringy and adheres to the substrate as shown in FIG.

If the circuit pattern becomes non-uniform in this way, various problems arise in circuit formation. For example, if it is a conductor paste, the thin part will increase the conductor resistance, if it is a resistor paste, it will cause a change in the resistance, and if it is an insulator, it will cause a decrease in withstand voltage. Furthermore, when a stringy phenomenon occurs at the terminal end, that part becomes extremely unstable, causing problems such as adhesion to unexpected locations. In particular, if the applied paste is a conductor paste, there is a risk that it will adhere to adjacent circuits and cause a short circuit.

This invention was made by focusing on the above-mentioned problems, and it is possible to prevent the stringing phenomenon at the end of the pattern, and form a circuit pattern at the end that has a uniform cross-sectional shape similar to the pattern of the steady discharge portion. The purpose of the present invention is to provide a circuit forming device that can obtain the desired results.

[Means for Solving the Problems] This invention discharges and shuts off circuit forming material from a nozzle by opening and closing a pneumatic control valve, and also connects a movable table on which a substrate material is installed and a nozzle to a circuit forming pattern. In the circuit forming apparatus, the circuit forming apparatus is configured to move the nozzle relatively in the horizontal direction, comprising: a nozzle elevating means for elevating the nozzle; and a table moving means for moving the nozzle so that the relative movement is started after a predetermined period of time has elapsed from the opening of the pneumatic control valve. After opening the pneumatic control valve, the nozzle is raised from a position where the distance between the nozzle and the substrate material is set to be smaller than the thick film of the circuit forming material to be discharged to a predetermined appropriate discharge position, and then the table is controlled to move. After the pneumatic control valve is closed, the nozzle is lowered from the appropriate position for discharging the circuit forming material to the thick film surface, and the table is stopped.

[Operation] In this invention, the distance between the nozzle and the substrate material is set to be smaller than the thickness of the paste to be discharged, and the nozzle rises to a predetermined appropriate discharge position while discharging the paste in response to a solenoid valve opening signal. After that, when the table is moved and the solenoid valve is closed, the nozzle descends to the thick film surface while attaching the steady discharge part, and controls the table so that the discharge part attaches to the rear end of the paste that has already been discharged and the table is stopped. Therefore, a thick film with a uniform cross-sectional shape similar to the thick film in the steady discharge portion can be obtained without causing stringiness at the terminal end.

[Embodiment of the invention] An embodiment of the invention will be described below with reference to FIGS. 1 to 4.
This will be explained based on the diagram. Note that the same or equivalent parts as in the conventional example are given the same reference numerals, and detailed explanation thereof will be omitted.

FIG. 1 is a block diagram showing a control system in this embodiment.

In the figure, 11 indicates the nozzle 3 and the air pressure source 1.
A solenoid valve 13 as a pneumatic control valve is interposed between the nozzle elevating mechanism A and the elevating mechanism driving device 13, which together with the nozzle elevating mechanism A constitutes a nozzle elevating means. 14 is a table driving device (table moving means) that drives the moving table 1; 15 is a ROM that stores a control program to be described later; and 16 is a lifting mechanism driving device that opens and closes the solenoid valve 11 according to this control program. 13
and a CPU (control means) as a table movement control means and a nozzle elevation control means for controlling the operation of the table drive device 14 and the like. Note that the other configurations are the same as those of the prior art example described above.

FIG. 2 is a flowchart showing the control program stored in the ROM 15, and the operation of this embodiment having the above configuration will be explained below based on this flowchart.

When the substrate material 2 is set at a predetermined position on the moving table 1 and an operation start command is sent, first in step 1, the pattern formation start position of the substrate material 2 and the nozzle 3 are aligned, the height of the nozzle 3 is set, etc. Perform initial settings. Thereafter, the solenoid valve 11 is opened in response to a solenoid valve opening signal from the CPU 16, compressed air is sent into the nozzle 3, and discharge of the paste Pa (see FIG. 3a) is started (step 2).
In this embodiment, in the above-mentioned initial setting,
As shown in Figure 3, the distance _h1 between the nozzle 3 and the substrate material 2 corresponds to the thickness h of the paste P to be discharged (see Figure 3c).
By setting it narrower, the unstable state until the paste P adheres to the substrate material 2 is alleviated. Thereafter, the nozzle 3 rises to a predetermined appropriate discharge position (height h ₃ above the substrate material 2) as shown in FIG. 3b while discharging the paste Pa (step 3). Furthermore, the discharge flow rate of paste Pa+Pb at the start of discharge is insufficient due to the first-order delay peculiar to air pressure control, as described above. During this first delay period, the moving table does not start moving, but starts moving in response to a movement start signal from the CPU 16 when the air pressure in the nozzle 3 reaches an appropriate value (step 4). Therefore, all of the paste Pa+Pb to be discharged during the first delay period is discharged to the pattern formation start point of the substrate material 2, and as shown in FIG. 3c, the amount of paste P deposited at this start point is There is no shortage compared to that part. When the end of pattern formation is reached, the solenoid valve 11 is closed by a solenoid valve close signal from the CPU 16 (state a in FIG. 4). At the same time, the CPU 16 also controls the lifting mechanism drive device 13.
A nozzle lowering signal is output from , and the nozzle 3 descends from the position shown in Fig. 4a through the position shown in Fig. 4b to the position shown in Fig. 4c, that is, the thick film surface, while depositing the steady discharge portion P. (Step 6). By the way, even if the solenoid valve 11 is closed, the portion Pd of the paste P shown by the two-dot chain line continues to be discharged from the nozzle 3. During this time, the movable table 1 continues to move, and conventionally the discharging portion
P ₂ (see FIG. 7C) becomes stringy, and this results in a long and thin extension toward the rear as shown by the broken line in FIG. 5. However, in this embodiment, when the solenoid valve 11 closes, At the same time, the nozzle descends and narrows the gap with the substrate material 2, so this discharge portion P ₂
does not become stringy, and is attached to the rear end of the steady discharge portion P, which has already been attached, as shown in FIG. Therefore, the rear end portion does not extend unnecessarily and does not adversely affect adjacent patterns. Note that the operation of the movable table 1 stops when the discharge of the discharge portion Pd is completed (step 7).

[Effects of the Invention] As explained above, according to the present invention, the end portion of the circuit pattern can prevent the stringing phenomenon, and can obtain a thick film having a uniform cross-sectional shape similar to the thick film of the steady discharge portion. There is.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a control system in an embodiment of the present invention, Fig. 2 is a flowchart showing control operations in this embodiment, and Figs. 3 a, b, c.
4 is a side view illustrating the operation of the paste discharging state at the start of pattern formation in this embodiment, and FIGS. 4a, b, and c are side views illustrating the operation showing the paste discharge state at the end of pattern formation in this embodiment , FIG. 5 is an explanatory side view showing the front end and rear end of the pattern formed by this embodiment, FIG. 6 is a perspective view showing a conventional circuit forming device, and FIG. 7a is an illustration of a solenoid valve. A diagram showing the opening/closing signal; Figure b is a diagram showing the discharge amount from the nozzle in response to the solenoid valve opening/closing signal;
FIG. 8c is a diagram showing a pattern discharge state by a conventional circuit forming apparatus, and FIG. 8 is a diagram showing a pattern discharge state (stringing state) after the electromagnetic valve is closed in the conventional circuit forming apparatus. 1...Moving table, 2...Substrate material, 3...
Nozzle, {A...lifting mechanism, 13...lifting mechanism drive device} nozzle lifting means, 16...CPU (lifting control means, table movement control means).

Claims (1)

[Claims] 1. Discharging and blocking the circuit forming material from the nozzle by opening and closing the pneumatic control valve, and moving the nozzle and the movable table on which the substrate material is installed relative to each other in the horizontal direction according to the circuit forming pattern. A circuit forming device configured to move the nozzle up and down, comprising: nozzle elevating means for elevating and lowering the nozzle; table moving means for moving so that the relative movement starts after a predetermined period of time has elapsed from the opening of the pneumatic control valve; After opening, the nozzle is raised from a position where the distance between the nozzle and the substrate material is set smaller than the thickness of the circuit forming material to be discharged to a predetermined appropriate discharge position, and then the table is controlled to move and the pneumatic control valve is closed. 1. A circuit forming apparatus comprising: a control means for controlling a nozzle to be lowered from an appropriate discharge position of a circuit forming material to a thick film surface and a table to be stopped after forming the circuit forming material.