JP6482914B2 - Printing device - Google Patents

Description

  The present invention relates to a printing electronics (also called printed electronics or printable electronics) technology, and more particularly to a printing apparatus for manufacturing an electronic device using an ink jet technology.

  Printed electronics are expected to develop as a new electronics field that is low in cost and low in environmental impact compared to conventional electronics using silicon. In particular, inkjet technology is a technology that allows non-contact material patterning on demand (and called “work”) and allows functional materials to be patterned on demand without waste. Application to the field is expected.

Ink jet technology is a method in which an ink jet head (called “head”) that can eject ink into fine droplets (this operation is referred to as “ejection”) is brought close to the work and the head or work is moved while moving the ink. Is controlled to perform patterning.
Here, as shown in Patent Documents 1 to 3, since the head and the work need to be brought close to each other, a flat work is usually used, but by attaching the head to the multi-axis robot, In addition, a technique that enables printing on a work having a three-dimensional curved surface (referred to as “three-dimensional work”) is also disclosed.

Japanese Patent Application Laid-Open No. 2014-111307 Special table 2011-514234 gazette JP 2009-113033 A

  By the way, the print quality in ink jet printing mainly depends on two points, the landing diameter and the landing accuracy. The landing diameter depends on the diameter of the droplet when ink is ejected. The smaller the landing diameter, the more precise and high-quality printing results can be obtained. The landing accuracy is generally higher as the kinetic energy of the droplets when ink is ejected is larger. This is because the greater the kinetic energy of the droplet (the larger the mass and velocity), the longer the distance for flying straight in the air, so that the ink can be landed at the intended position. Here, when the droplet diameter is small, the landing diameter is small but the kinetic energy is also small, so the distance that the droplets fly straight in the air is short. This means that the distance between the head and the workpiece (called “working distance”) must be shortened. In general, an inkjet head for flat work has no problem even if the working distance is short. Therefore, a drop-on-demand (DoD) type, which is easy to make droplets small, is adopted, and print quality is improved by reducing the landing diameter. This is the basic technical idea.

  Patent Documents 1 and 2 show that inkjet printing can be performed on a three-dimensional workpiece by attaching the head to a multi-axis robot. However, there is no description regarding the method of the ink jet head, and the problem of the above working distance is completely unknown. If it is assumed that a DoD type inkjet head for general planar work is used, a commercially available head is not supposed to be used for this purpose, so the working distance is usually quite short (typically 1 mm or less). In this case, since there are inevitably locations where the working distance locally increases on the curved surface, the landing position deviation tends to occur as a result. In the case of printed electronics, even if only one landing position deviation occurs, this problem is serious because it causes an electrical short circuit or disconnection, resulting in malfunction of the entire electronic device.

Patent Document 3 discloses an example in which a continuous ink jet (CIJ) is attached to a multi-axis robot. The CIJ type is a method that adjusts the landing position by bending the droplet trajectory with a high electric field after the ink is pressurized and ejected from the nozzle at a high speed and then divided into droplets. Can be secured enough.
However, the CIJ type generally has a large landing diameter (typically about 1 mm) and is not suitable for high-precision printing (typically 100 μm or less) required for printing electronics. Furthermore, the CIJ type requires the conditions required for the ink to be used, such as that it is necessary to charge the ink droplets, and that measures against changes in the properties of the ink by constantly circulating in the atmosphere are required. Since it is much stricter than the mold, it is actually difficult to develop a CIJ ink jet ink suitable for printing electronics.

  That is, the conventional printing apparatus has a problem that inkjet printing cannot be performed on a three-dimensional workpiece with high print quality required for printing electronics.

  Further, when trying to perform high-precision printing, there is a serious problem caused by using a multi-axis robot for head positioning. Since a multi-axis robot is a mechanism that performs positioning by combining a plurality of rotation axes, in principle, it is not good at linear movement (referred to as “linear motion”) in a specific direction. That is, even if an attempt is made to move between two arbitrary points by linear movement, the actual locus becomes a meandering locus formed by combining a plurality of arcs. The amplitude of this serpentine trajectory can typically occur on the order of a few millimeters. In addition, the trajectory always varies depending on the absolute position of each axis, the operation speed, and other external factors, and it is difficult to accurately predict the trajectory in advance. In such a state, there has been a problem that the multi-axis robot cannot be applied as it is to printing type electronics that require accuracy of 100 μm or less.

Furthermore, in a printed electronics device using an inkjet, it is essential to observe and monitor the ejection state of the head at a high frequency. This is because ink used in printing electronics becomes a solid material that develops electrical characteristics after drying, and if ink drying occurs in the vicinity of the ejection port (called “nozzle”) of the head, ejection failure This is because the printing process cannot be executed.
The observation and monitoring of the ejection state of the head is typically performed by an imaging device having a resolution of about several μm and a strobe light source. Here, since the resolution of the imaging device is high, the depth of field of the imaging device is inevitably small (typically about several μm). Therefore, high-precision head positioning is required for observing and monitoring the ejection state of the head, but here too, there is a problem of insufficient positioning accuracy of the multi-axis robot. That is, even if the head is moved to the droplet observation position, it is difficult to precisely position the droplet at a position where the droplet can be observed, which causes a serious hindrance to observation and monitoring of the ejection state of the head. In this respect as well, there is a problem that the multi-axis robot cannot be applied to the printed electronics as it is.

  Furthermore, in a printed electronics device using an ink jet for a three-dimensional workpiece, in addition to the working distance, an angle between the head and the workpiece (referred to as a “working angle”) is also important. Patent Documents 1 to 3 disclose the measurement and use of the working distance by the distance sensor, but the distance measurement value only indicates the working distance, and does not disclose the measurement and use of the working angle.

In view of such problems, the inventors have conducted intensive research and solved the above problems by the following technical idea.
That is, in order to achieve both (1) a small landing diameter and (2) a high landing accuracy, the technical idea is to increase the speed after reducing the droplet size. This technical idea could be realized by using a push type ink jet head.

  Furthermore, the problems caused by insufficient position accuracy of multi-axis robots can be solved by attaching a highly accurate linear motion mechanism to the tip of the multi-axis robot and operating it in coordination with the movement of the multi-axis robot. I was able to.

  Furthermore, the measurement and use of the working angle can be realized by using a plurality of non-contact sensors and a distance data calculation unit.

As a result, the present invention has led to the invention of a printing apparatus that can perform inkjet printing on a three-dimensional workpiece with high print quality required by printing electronics using a multi-axis robot.
Therefore, an object of the present invention is to provide a printing apparatus capable of performing inkjet printing on a three-dimensional workpiece with high print quality required by printing electronics using an axial robot.

A printing apparatus according to the present invention made to achieve the above object is a printing apparatus for manufacturing an electronic device, wherein a push-type inkjet head and an ink discharge unit including a linear motion mechanism are arranged at the tip of a multi-axis robot. The push type inkjet head is attached to the linear motion mechanism, and the multi-axis robot has a function capable of independently controlling the height, the horizontal plane position, and the inclination of the push type inkjet head. has the linear motion mechanism, the attached to the tip of the multi-axis robot, the have a high positioning accuracy than multi-axis robot, and the linear motion mechanism, the movable shaft of the three axes orthogonal to each other And a plurality of non-contact distance sensors and a distance data calculation unit, wherein the plurality of non-contact distance sensors Attached to the tip of the robot, and outputs distance data from the tip of the multi-axis robot to the printed material, and the distance data calculation unit is electrically connected to the plurality of non-contact distance sensors, and the distance Based on the data, it has a function of calculating the distance and angle from the push-type inkjet head to the substrate, and when the difference between the distance data of the plurality of distance sensors is regarded as 0, the plurality of distances The average value of data is a working distance, an adjustment value is determined based on the working distance, and the working distance is adjusted by a linear motion mechanism .
The push type ink jet head means a piezoelectric element type ink jet head.

Here, it is desirable to have an imaging unit and a light source, dispose the push type inkjet head between the imaging unit and the light source, and observe ink droplets ejected from the push type inkjet head .
The imaging unit and the light source are preferably attached to a tip of the multi-axis robot, and each of the imaging unit and the light source preferably has one light reflecting mirror.

According to the present invention, inkjet printing can be performed on a three-dimensional workpiece with high print quality required for printing electronics.
As a result, the advantage of the ink jet printing technology that does not select the material of the workpiece is further expanded, and it is possible to directly print electronic circuits on workpieces of various shapes. Although the present invention can be applied to various technical fields, typically, the technical field in which an electronic circuit is directly formed on a vehicle-mounted part having a curved surface such as glass or injection-molded resin has great potential in the market. is there.

The figure explaining an example of the external appearance of the apparatus concerning this invention. The figure explaining an example of a structure of the inkjet discharge unit which the apparatus concerning this invention has. FIG. 3 is a diagram illustrating an example of a configuration of a push-type ink jet head included in an apparatus according to the present invention. The figure explaining an example of a structure of the linear motion mechanism which the apparatus concerning this invention has. The figure explaining an example of a structure of the linear motion mechanism which the apparatus concerning this invention has. The figure explaining an example of a structure of the linear motion mechanism which the apparatus concerning this invention has. The figure explaining an example of the discharge observation state of the apparatus concerning this invention. The figure explaining an example of a structure of the inkjet discharge unit which the apparatus concerning this invention has. The figure explaining an example of a structure of the inkjet discharge unit which the apparatus concerning this invention has. The figure explaining an example of a structure of the inkjet discharge unit which the apparatus concerning this invention has.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated, referring drawings. The embodiments described herein are made to embody the technical idea of the present invention and facilitate the description, and do not limit the embodiments. Moreover, all the technical elements demonstrated from now on can be combined suitably within the range of the technical idea concerning this invention.
(First embodiment)

In the present embodiment, the most basic technical elements according to the present invention and their mutual relationship will be described.
As shown in FIGS. 1 and 2, the most basic technical elements according to the present invention are a multi-axis robot 1, a push-type inkjet head 3, and a linear motion mechanism 4. In the description of the present embodiment, as an example of the technical idea according to the present invention, the push-type inkjet head 3 and the linear motion mechanism 4 are combined to form the inkjet discharge unit 2, and the inkjet discharge unit 2 is used as the multi-axis robot 1. Let's take up the form of attaching to the tip of the. That is, the push type inkjet head 3 is connected to the multi-axis robot 1 via the linear motion mechanism 4 and the inkjet discharge unit 2.

With reference to FIG. 1, each part of the multi-axis robot 1 will be described.
The multi-axis robot 1 includes a pedestal 10, a first rotating shaft 11, a second rotating shaft 12, a third rotating shaft 13, a fourth rotating shaft 14, a fifth rotating shaft 15, and a sixth rotating shaft. The shaft 16 and the inkjet discharge unit 2 are provided.
The intent of using the multi-axis robot 1 in the present invention is to allow the height, horizontal position, and inclination of the inkjet discharge unit 2 to be set as freely as possible. If the number of axes is increased, This is preferable because positioning can be performed with a higher degree of freedom. On the other hand, if the number of axes is reduced, the operation is simple and easy to understand because the number of parameters is small. As described above, the configuration of the multi-axis robot 1 can be appropriately selected according to the printing object and the purpose of printing.

Next, with reference to FIG. 2, each part of the inkjet discharge unit 2 in this Embodiment is demonstrated.
The ink jet discharge unit 2 includes a push type ink jet head 3 and a linear motion mechanism 4. The push type ink jet head 3 is attached to the ink jet discharge unit 2 via a linear motion mechanism 4 and has a function of discharging ink onto a work. The linear motion mechanism 4 has higher positioning accuracy than the multi-axis robot 1 (typically several μm), and has a function of precisely positioning the push-type inkjet head 3.

The multi-axis robot 1 has a function that allows the height, horizontal position, and inclination of the inkjet discharge unit 2 to be freely set within its operating range, so that even if the workpiece has a three-dimensional curved surface, Even if the printing surface is not horizontal but inclined, the height, horizontal position, and inclination of the inkjet discharge unit 2 can be set correspondingly, and printing can be performed directly on the workpiece.
However, while the degree of freedom in positioning is high, the accuracy is not necessarily high. As a printing apparatus for printing electronics, it is necessary to be able to aim at a landing position of at least 100 μm pinpoint.

According to the printing apparatus in the present embodiment, the linear motion mechanism 4 can significantly reduce the positioning accuracy and the number of times required for the multi-axis robot 1. That is, the multi-axis robot 1 performs positioning at one point within the movable range (typically about several tens of millimeters) of the linear motion mechanism 4, and performs printing by moving the linear motion mechanism 4 at that position. Within the movable range of the linear motion mechanism 4, printing can be performed with high positioning accuracy of the linear motion mechanism 4.
Then, when printing within the movable range of the linear motion mechanism 4 is completed, the multi-axis robot 1 is used to move to one point within the next range, where the linear motion mechanism 4 is moved again to perform printing. By repeating this, even if the printing range is wide, it is possible to perform printing with an overwhelmingly small number of positioning times compared to the case where the linear motion mechanism 4 is not provided.

  Next, the configuration of the linear motion mechanism 4 will be described in detail with reference to FIGS. 4a to 4c. The linear motion mechanism 4 can change the number of axes as appropriate.

  FIG. 4 a is a schematic diagram when only the first uniaxial linear motion mechanism 4 a is used as the linear motion mechanism 4. In this case, the linear motion mechanism 4 can be operated with high accuracy in one direction. This is effective when, for example, the push-type ink jet head 3 having a large number (typically, several tens to several hundreds) of nozzles is used. This is because if the push-type inkjet head 3 has a large number of nozzles, a wide range of printing can be performed at a high speed by a single linear motion.

FIG. 4B is a schematic view when the first uniaxial linear motion mechanism 4a and the second uniaxial linear motion mechanism 4b, which are connected so that the movable axes are orthogonal to each other, are used as the linear motion mechanism 4. .
In this case, the linear motion mechanism 4 can be operated with high accuracy in two directions. With this configuration, it is possible to select either the case where the two movable axes are parallel to the workpiece surface (parallel arrangement) or the case where one is parallel and the other is vertical (vertical arrangement). It is.
The parallel arrangement is effective when the push-type inkjet head 3 having a small number (typically 1 to a dozen or more) nozzles is used. When the number of nozzles of the push-type inkjet head 3 is small, it is not possible to print over a wide range with one linear motion, but by performing a two-dimensional scanning operation, the same as when many nozzles are provided This is because a wide range of printing is possible.
The vertical arrangement is effective when the push-type inkjet head 3 has a large number of nozzles and when it is necessary to precisely control the working distance.

FIG. 4c shows the first uniaxial linear motion mechanism 4a, the second uniaxial linear motion mechanism 4b, and the third uniaxial linear motion mechanism, which are connected so that the movable axes are orthogonal to each other. It is a schematic diagram at the time of using 4c.
In this case, the linear motion mechanism 4 can be operated with high accuracy in three directions. This configuration is effective when the push-type inkjet head 3 having a small number of nozzles is used and the working distance needs to be precisely controlled.
Even when the push-type inkjet head 3 having a large number of nozzles is used, the configuration having three movable shafts is effective. This is because this makes it possible to perform high-speed and high-definition printing while providing a function for precisely controlling the working distance even when the printing range is wider.

Here, how effective it is with respect to ink jet printing using the multi-axis robot 1 will be described with an example.
As an example, the number of nozzles of the push-type inkjet head 3 is one, the printing range is 100 mm × 100 mm, the movable shaft of the linear motion mechanism 4 is two in parallel, the movable range is 20 mm × 20 mm, and the landing position accuracy is 100 μm. Think about the case.

First, when the linear motion mechanism 4 is not provided, it is difficult to achieve a landing position accuracy of 100 μm in the first place. Therefore, when the linear motion mechanism 4 is provided, there is an overwhelming advantage. However, since this cannot be compared, it is assumed that positioning of 100 μm is possible with a single multi-axis robot.
In order to position the push-type inkjet head 3 with the multi-axis robot 1 alone, it is necessary to perform position teaching at all landing positions. The number of teaching points is 100 mm × 100 mm, and the range of one point is 100 μm × 100 μm, so the total number is 1000000 points. It is easy to imagine how much effort, effort, and time to teach these million points, and it is almost impossible to execute.
On the other hand, when the linear motion mechanism 4 having a movable range of 20 mm × 20 mm is provided, the number of teaching points is reduced to 25 points. If the teaching is 25 points, it is sufficiently feasible and easy to apply. It should be emphasized that such an overwhelming effect can be obtained by the present invention.

As a printing method, as disclosed in the prior art, a method of printing by directly moving the multi-axis robot 1 is also conceivable. However, as described in the problem item, the actual trajectory meanders. Therefore, since it is difficult to predict, it is difficult to apply except in a limited situation (several mm meandering is allowed and fluctuation is within the range of prediction), causing a problem in versatility.
Since the basis of the technical idea of the present invention is to ensure versatility for high-definition inkjet printing (corresponding to workpieces of various shapes), the method of printing by moving the multi-axis robot 1 directly is as follows: The printing method according to the present invention is not suitable.

Next, a detailed configuration of the push-type inkjet head 3 will be described.
The technical idea according to the present invention is to increase the speed after reducing the droplet size in order to achieve both a small landing diameter and high landing accuracy. Based on this idea, as a result of diligent research on the optimal ink jet system for three-dimensional workpieces, it was concluded that the push type ink jet head is optimal.
The push type is also called a piston type and is classified as one of DoD type ink jets. A feature of the push-type ink jet head is that a force for pushing out a droplet can be increased simultaneously (a force can be efficiently placed on the droplet) while realizing a small droplet diameter.

As a result of research, it has been found that such a push-type feature is realized by a mechanical structure as shown in FIG.
FIG. 3 shows the structure of the push-type ink jet head 3 according to the present invention. The push-type ink jet head 3 according to the present invention includes an orifice 21, an ink reservoir 22, a partition wall 23, a piezoelectric element 24, Have

Furthermore, it has been found that the first characteristic “magnitude of force” can be obtained by the shape of the piezoelectric element 24.
The piezoelectric element 24 has a structure that is fixed on the opposite side of the partition wall 23 so that the long side direction is displaced the most when a voltage is applied. The displacement amount increases as the piezoelectric element 24 becomes longer. Research has shown that the device according to the present invention has sufficient force when the length of the longest side of the piezoelectric element 24 is a rectangular parallelepiped shape that is five times or more the length of the shortest side.

As for the second feature, “Efficiently placing the force on the droplet”, the piezoelectric element 24, the partition wall 23, the ink reservoir 22 and the orifice 21 are the same as shown in FIG. This is caused by being arranged on a straight line.
The force obtained by the piezoelectric element 24 is transmitted to the ink reservoir 22 through the partition wall 23, propagates as a pressure wave in the ink reservoir 22, and becomes kinetic energy that causes droplets to fly through the orifice 21. At this time, the piezoelectric element 24, the partition wall 23, the ink reservoir 22, and the orifice 21 are arranged on the same straight line, so that the force generated in the piezoelectric element 24 is efficiently transmitted to the droplet. is there. On the other hand, for example, if they are not on the same straight line, the generated pressure wave is repeatedly reflected and attenuated inside the ink reservoir 22 to reach the orifice 21 and is given to the droplet accordingly. The kinetic energy becomes smaller.

As described above, the force generated by the piezoelectric element 24 is efficiently applied to the droplet, and the diameter of the orifice 21 is reduced, whereby the droplet diameter can be reduced and the speed can be increased.
Specifically, the droplet diameter can be reduced so that the landing diameter can be 100 μm or less, and at the same time, the droplet speed can be increased so that the working distance can be 30 mm or more.
Here, when the landing diameter and the working distance are independently compared with the prior art, they may not be so excellent values. However, I think that it is important to be able to balance these two.

In addition, the structure of the ink jet head as shown in FIG. 3 is difficult to shorten the distance between the nozzles when the plurality of nozzles are arranged in the same head due to the presence of the ink storage section 22. Since it seems to be disadvantageous at first glance, it is a structure that has not been omitted so far.
However, this structure makes it possible to achieve both a small landing diameter and high landing accuracy, and is an excellent solution for realizing printed electronics for 3D workpieces.
(Second Embodiment)

  In the present embodiment, a description will be given of an apparatus configuration example that can observe and monitor the ejection state of the head in the printing apparatus using the multi-axis robot 1. In the first embodiment, it has been described in detail that using the linear motion mechanism 4 gives an overwhelming advantage with respect to ink jet printing using the multi-axis robot 1. In the present embodiment, it will be described that the linear motion mechanism 4 has a great advantage in observing and monitoring the ejection state of the head.

FIG. 5 is a diagram showing an example of a device configuration in the case of observing and monitoring the ejection state of the head using the inkjet ejection unit 2 according to the first embodiment shown in FIG.
In FIG. 5, the inkjet discharge unit 2 includes a push-type inkjet head 3 and a linear motion mechanism 4. Furthermore, the apparatus according to the present embodiment includes a discharge observation unit support unit 9, an imaging unit 5, and a light source 6.
The imaging unit 5 and the light source 6 are respectively attached to the ejection observation unit support unit 9, and the imaging unit 5 and the light source 6 are arranged linearly. In such an arrangement, the inkjet discharge unit 2 is brought close to the imaging unit 5 and the light source 6 by using the positioning mechanism of the multi-axis robot 1.
Then, by disposing the push type inkjet head 3 between the imaging unit 5 and the light source 6, it is possible to observe ink droplets ejected from the push type inkjet head 3.

  However, in this case, even if the push-type inkjet head 3 is positioned only by the multi-axis robot 1, it is difficult to position the push-type inkjet head 3 reliably at the observation position. This is because, in the printing apparatus according to the present invention, the ink droplets are as small as 100 μm or less, so that the spatial resolution required for the imaging unit 5 is high (typically several μm), and as a result, the imaging unit 5 Since the depth of field (the in-focus range) is extremely small (typically several μm), high-accuracy positioning is required to reliably position the ink droplet in the in-focus range. This is because a mechanism (typically several μm) is required.

Therefore, it is possible to reliably position the ink droplet at the observation position by using the linear motion mechanism 4 having the function of precisely positioning the push-type inkjet head 3 that is the configuration shown in the first embodiment. It becomes.
At this time, the linear motion mechanism 4 preferably has three movable shafts as shown in FIG. 4c. This is because the precise positioning of the ink droplets is performed in a three-dimensional space, and therefore it is necessary to precisely position the ink droplets at an optimum position with the three movable axes.

However, even if the number of movable axes of the linear motion mechanism 4 is one or two, it is possible to reliably position the ink droplet at the observation position.
For example, when the number of movable axes of the linear motion mechanism 4 is two, the remaining one movable axis may be incorporated into the discharge observation unit support unit 9. Similarly, when the number of movable axes of the linear motion mechanism 4 is one, the remaining two movable axes may be incorporated into the discharge observation unit support unit 9.
In this way, when a part of the number of the three movable axes necessary for observation is incorporated into the discharge observation unit support unit 9, the movable range and positioning accuracy of the movable axis are specialized for observation. Can be designed.

Next, another configuration capable of observing and monitoring the ejection state of the head will be described.
FIG. 6 is a diagram illustrating a configuration when the imaging unit 5 and the light source 6 are incorporated in the inkjet discharge unit 2.
The inkjet discharge unit 2 includes a push-type inkjet head 3, a linear motion mechanism 4, an imaging unit 5, a light source 6, a first light reflection mirror 7a, and a second light reflection mirror 7b.
The push type ink jet head 3 is attached to the ink jet discharge unit 2 via a linear motion mechanism 4. The imaging unit 5 and the light source 6 are attached to the inkjet discharge unit 2 in a direction parallel to the direction of ink droplets discharged from the push-type inkjet head 3. The first light reflecting mirror 7a and the second light reflecting mirror 7b are configured so that the light emitted from the light source 6 is reflected by the second light reflecting mirror 7b and the first light reflecting mirror 7a, respectively, and the imaging unit 5 It is attached to the inside of the inkjet discharge unit 2 so as to reach.
By arranging in this way, it is possible to avoid disposing the imaging unit 5 and the light source 6 in a region located at the tip of the push-type inkjet head 3, so that the imaging unit 5 and the light source 6 are connected to the workpiece during the printing operation. Interference can be avoided.
Here, the linear motion mechanism 4 preferably has three movable axes as shown in FIG. 4c. This is because the precise positioning of the ink droplets is performed in a three-dimensional space, and therefore it is necessary to precisely position the ink droplets at an optimum position with the three movable axes.

However, as in the case of FIG. 5, even if the linear motion mechanism 4 has one or two movable axes, it is possible to reliably position the ink droplet at the observation position.
For example, when the number of movable axes of the linear motion mechanism 4 is two, the remaining one movable axis may be incorporated into the imaging unit 5 and the light source 6. In the configuration of FIG. 6, as the imaging unit 5 and the light source 6 are brought closer to the push-type inkjet head 3, it is possible to observe an ink droplet at a position farther from the push-type inkjet head 3. Similarly, when the number of movable axes of the linear motion mechanism 4 is one, the remaining two movable axes may be incorporated into the imaging unit 5 and the light source 6.
As described above, when a part of the number of three movable axes necessary for observation is incorporated in the imaging unit 5 and the light source 6, the movable range and positioning accuracy of the movable axes are specialized for observation. Can be designed.

As shown in FIG. 6, when the imaging unit 5 and the light source 6 are incorporated in the inkjet discharge unit 2, a further preferable effect can be obtained.
That is, without moving the inkjet discharge unit 2 to a predetermined discharge observation position (in the example of FIG. 5, the position where the discharge observation unit support unit 9 is installed), regardless of the operation state of the multi-axis robot 1, It is a point which can observe and monitor a discharge state. As a result, it is possible to immediately observe and monitor the discharge state regardless of the operation state, so that it is possible to quickly check and deal with the change in the discharge state.
If the image pickup unit 5 and the light source 6 are attached to the inkjet discharge unit 2 via the linear motion mechanism 4 in the same manner as the push inkjet head 3, the push inkjet head 3 is in the midst of linear motion. However, since observation can be continued, it is further preferable.
(Third embodiment)

  In the present embodiment, a configuration example in which a working distance and a working angle during a printing operation can be measured and used will be described. FIG. 7 is an example of a device configuration when a working distance and a working angle measurement function are added to the inkjet discharge unit 2 described in the first embodiment.

The inkjet discharge unit 2 in FIG. 7 includes a push-type inkjet head 3, a linear motion mechanism 4, a first non-contact distance sensor 8a, a second non-contact distance sensor 8b, and a third non-contact distance sensor 8c. And a fourth non-contact distance sensor 8d.
The push-type inkjet head 3 is attached to the inkjet discharge unit 2 via the linear motion mechanism 4, and the first to fourth non-contact distance sensors 8 a to 8 d are symmetrical relative to the tip of the inkjet discharge unit 2. It is attached with.
Further, the first to fourth non-contact distance sensors 8a to 8d are electrically connected to the distance data calculation unit 40 through wiring. The distance data calculation unit 40 may be installed inside the inkjet discharge unit 2 or may be installed outside.

Signals generated from the first to fourth non-contact distance sensors 8a to 8d are respectively sent to the distance data calculation unit 40 and calculated as distance data. The distance data calculation unit 40 calculates an average value and a difference of the distance data based on the obtained plurality of distance data. The average value of the distance data represents a substantial working distance, and the difference of the distance data represents a substantial working angle. Here, typically, it is preferable to control the working angle to be 90 °. Therefore, the angle of the inkjet discharge unit 2 is set so that the difference of the distance data is as close to 0 as possible. It is preferable to control using. When the distance data difference can be regarded as 0, the average value of the plurality of distance data is handled as a substantial working distance.
Here, when the working distance can be precisely adjusted by the linear motion mechanism 4, the adjustment value can be determined based on the substantial working distance calculated in this way. That is, the presence of the linear motion mechanism 4 makes it possible to use the working distance measurement function as described in this embodiment more effectively.

  In the present embodiment, the total number of non-contact distance sensors has been described as four. However, in the technical idea of the present embodiment, there may be a plurality of sensors, and the number is not limited to four. Absent. For example, when the total number of sensors is two, the working angle for one specific direction and the substantial working distance can be calculated in the same manner as described above. When the total number of sensors is 3, the working angle with respect to a specific two directions and the substantial working distance can be similarly calculated by the method described above. When the total number of sensors is 4 or more, it is possible to detect, measure, and use finer distances, such as correction by differences in working angles for more directions or detection positions (distance from the push-type inkjet head 3). preferable.

FIG. 8 shows an apparatus configuration example in the case where a working distance and a working angle measurement function are added to the inkjet discharge unit 2 described in the second embodiment.
8 includes a push-type inkjet head 3, a linear motion mechanism 4, an imaging unit 5, a light source 6, a first light reflecting mirror 7a, a second light reflecting mirror 7b, A non-contact distance sensor 8a, a second non-contact distance sensor 8b, a third non-contact distance sensor 8c, and a fourth non-contact distance sensor 8d.
The push-type inkjet head 3 is attached to the inkjet discharge unit 2 via the linear motion mechanism 4, and the imaging unit 5 and the light source 6 perform inkjet in a direction parallel to the direction of ink droplets discharged from the push-type inkjet head 3. It is attached to the discharge unit 2.
The first light reflecting mirror 7a and the second light reflecting mirror 7b are configured so that the light emitted from the light source 6 is reflected by the second light reflecting mirror 7b and the first light reflecting mirror 7a, respectively, and the imaging unit 5 It is attached to the inside of the inkjet discharge unit 2 so as to reach.
The first to fourth non-contact distance sensors 8a to 8d are attached to the tip of the inkjet discharge unit 2 with symmetrical positional relationships. Further, the first to fourth non-contact distance sensors 8a to 8d are electrically connected to the distance data calculation unit 40 through wiring.
The distance data calculation unit 40 may be installed inside the inkjet discharge unit 2 or may be installed outside.

The method for processing and using the signals generated from the first to fourth non-contact distance sensors 8a to 8d are as described above, but in the case of the configuration shown in FIG. 8, a further preferable effect can be obtained.
In the printing method according to the present invention, the working distance and the working angle are usually measured in order to perform the printing procedure after positioning the multi-axis robot 1 including the measurement of the working distance and the working angle. Do not print while you are.
During this time, the push-type inkjet head 3 is intermittently exposed to vibrations associated with the positioning of the multi-axis robot 1, so the multi-axis robot 1 is positioned during the push-type inkjet head 3. In particular, it becomes a state that requires attention to ejection failure.
Here, with the configuration shown in FIG. 8, the discharge state can always be observed and monitored even during the positioning of the multi-axis robot 1. It becomes possible to do. When observing the ejection state in a non-printing state, it is more preferable to have a structure in which a shielding object can be inserted between the push-type inkjet head 3 and the work in order to prevent unintended ink adhesion.

DESCRIPTION OF SYMBOLS 1 ... Multi-axis type robot 2 ... Inkjet discharge unit 3 ... Push type inkjet head 4 ... Linear motion mechanism 4a ... 1st 1 axis | shaft linear motion mechanism 4b ... 2nd 1 Axis linear motion mechanism 4c ... third uniaxial linear motion mechanism 5 ... imaging unit 6 ... light source 7a ... first light reflecting mirror 7b ... second light reflecting mirror 8a ... 1st non-contact distance sensor 8b ... 2nd non-contact distance sensor 8c ... 3rd non-contact distance sensor 8d ... 4th non-contact distance sensor 9 ... discharge observation unit support part DESCRIPTION OF SYMBOLS 10 ... Base part 11 ... 1st rotating shaft 12 ... 2nd rotating shaft 13 ... 3rd rotating shaft 14 ... 4th rotating shaft 15 ... 5th rotation Axis 16 ... sixth rotation axis 21 ... orifice 22 ... ink reservoir 23 ... partition wall 24 ... piezoelectric element 40 ... Away data calculation unit

Claims (3)

A printing apparatus for manufacturing an electronic device,
An ink discharge unit equipped with a push-type inkjet head and a linear motion mechanism is attached to the tip of a multi-axis robot,
The push-type inkjet head is attached to the linear motion mechanism,
The multi-axis robot has a function capable of independently controlling the height, the horizontal plane position, and the inclination of the push-type inkjet head,
The linear motion mechanism is attached to the distal end of the multi-axis robot, it has a high positioning precision than the multi-axis robot, and the linear motion mechanism includes a movable shaft of the three axes orthogonal to each other,
Furthermore, it has a plurality of non-contact distance sensors, and a distance data calculation unit, the plurality of non-contact distance sensors are attached to the tip of the multi-axis robot,
Each of the distance data from the tip of the multi-axis robot to the printing material is output, and the distance data calculation unit is electrically connected to the plurality of non-contact distance sensors, and the push type based on the distance data Has a function to calculate the distance and angle from the inkjet head to the substrate,
When the difference between the distance data of multiple distance sensors is considered to be 0, the working distance is the average value of the multiple distance data,
An adjustment value is determined based on the working distance, and the working distance is adjusted by a linear motion mechanism . An imaging unit and a light source;
The push type inkjet head is disposed between the imaging unit and the light source,
The printing apparatus according to claim 1, wherein the ink droplets ejected from the push-type inkjet head are observed . The printing apparatus according to claim 2 , wherein the imaging unit and the light source are attached to a tip of the multi-axis robot, and each has one light reflecting mirror for the imaging unit and the light source.

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