JPH0680884B2 - Thick film drawing machine nozzle - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle of a thick film drawing machine used for forming a thick film circuit of a radio receiver, a television receiver, a video tape recorder, a communication device and the like.

2. Description of the Related Art A thick film circuit is generally formed by a screen printing method in which a thick plate paste is printed in a desired shape on a substrate surface using a screen printing plate, and a drying and baking process is performed to form the thick film paste.

Furthermore, in recent years, a drawing method has been proposed in which a paste is discharged from a discharge hole at the tip of a nozzle and a conductor or a resistor is formed while moving the nozzle relative to a substrate for high-mix low-volume production. In the drawing method, patterns can be switched in a short time by computer control, and circuit prototypes can be made simply by creating program data.
The development period can be greatly shortened, and it is considered to be a powerful thick film circuit formation method that replaces the screen printing method.

The nozzle tip portion is shown in FIGS. 4 and 5 in the above thick film drawing machine. Figure 4 shows a circular nozzle 1a with a typical diameter of 100 μm.
A paste discharge hole 10 of about 300 μm is provided. Fifth
In the figure, the paste discharge hole 11 is formed in a slit shape, and its longitudinal direction is arranged at 90 ° with respect to the nozzle advancing direction, and a relatively wide conductor or resistor is formed in a short time with high accuracy. The drawing nozzle 1b. This is more efficient than a circular nozzle that draws thin and wide lines by adjoining several line widths.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the above slit-shaped discharge holes, the widths of the conductor and the resistor are fixed, and the paste is filled in the nozzles of several kinds of slit widths required in advance in mass production, It is possible to replace it at the time of use, or prepare a drawing machine for each resistance width and conductor width and put it on standby. Either method requires a large number of nozzles or drawing machines.

Means for Solving the Problems In order to solve the above problems, the present invention allows the paste to be discharged from a discharge hole at the tip of the nozzle under pressure while simultaneously moving the nozzle relative to the substrate. In a thick film drawing machine that forms conductors or resistors on a substrate, the nozzle discharge holes are formed in a slit shape, and the slit discharge holes are arranged so that the longitudinal direction is approximately 90 ° with respect to the nozzle advancing direction. However, it is characterized in that a movable piece urged in the direction of narrowing the slit width is arranged at the end of the discharge hole.

The pressure applied to the paste includes air pressure, mechanical pressure by a plunger, and the like, and it is preferable to provide a pressure adjusting device so that these pressures can be arbitrarily changed. Further, the movable pieces are optimally arranged at both ends of the discharge hole, but may be arranged only at one end. Further, a coil spring, a leaf spring, a magnet, or the like can be used as a means for urging the movable piece in the direction of narrowing the slit width.

Function In the present invention, the slit-shaped discharge holes are for discharging the paste filled in the nozzle body while forming it into a thick film and adhering it to the substrate surface. The movable piece at the end of the slit is variable by the back pressure generated when the paste reaches the substrate surface. Alternatively, the width of the resistor can be arbitrarily changed by adjusting the pressure applied to the paste.

Examples Hereinafter, the present invention will be described based on Examples.

In FIG. 1, 1 is a main nozzle, 2 is a paste, 3 is a coil spring, 4 is a movable piece, and 5 is an insulating substrate.

First, the movable piece 4 is attached to the main body nozzle 1 at least in a shape that does not drop on the substrate 5. The movable piece 4 has a sliding effect so as to slide over the entire space of the slit-shaped ejection hole 6, and the coil spring 3 is attached to both ends of the main body nozzle 1 and the empty space of the movable piece 4. The movable piece 4 is pushed by the coil spring 3 and tries to close the slit-shaped discharge hole 6. Next, the above-mentioned nozzle is filled with the paste 2 and attached to a thick film writer head, and the insulating substrate 5 and the tip of the nozzle are brought close to each other so as to be at least 50 μm or less. In this case, in order to keep the distance constant, it is desirable to make a contact (not shown) using a diamond tip follow the mounting substrate 5 at the tip of the nozzle.

When the paste 2 is discharged by the air pressure under the above conditions, the back pressure is generated at the same time when the paste 2 reaches the surface of the substrate 5,
An operation of pushing open the movable piece 4 is performed. The slit width of the slit-shaped discharge hole 6 is determined at the place where the pressure of the coil spring 3 and the back pressure are balanced. The slit width required to obtain the predetermined resistor width and conductor width can be selected by adjusting the air pressure.

EFFECTS OF THE INVENTION As described above, the present invention can easily and quickly form a resistor or conductor of any width with a single nozzle. Not only can the cost of the membrane circuit board be reduced, but the device switching time can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a sectional view of a drawing nozzle in one embodiment of the present invention, FIG. 2 is a bottom view of the drawing nozzle in one embodiment of the present invention, and FIG. 3 is a drawing nozzle of the embodiment in the present invention. FIG. 4 and FIG. 5 are cross-sectional views seen from the side, and are perspective views of a conventional drawing nozzle. 2 ... Paste, 3 ... Coil spring, 4 ... Movable piece, 5
…… Substrate, 6 …… Discharge hole.

Claims (1)

[Claims] Claim: What is claimed is: 1. A thick film drawing method, wherein a paste is discharged from a discharge hole at the tip of a nozzle while pressure is applied, and at the same time, a conductor or a resistor is formed on the substrate while moving the nozzle relative to the substrate. In the machine, the discharge hole of the nozzle is formed in a slit shape, and the slit-shaped discharge hole is arranged so that the longitudinal direction thereof is approximately 90 ° with respect to the nozzle traveling direction, and the slit width is narrowed at the end of the discharge hole. A nozzle for a thick film drawing machine, which is provided with a movable piece biased in a direction.