JP2000079703A - Method and apparatus for positioning ink-jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To position a head with high precision by picking up an image of a different nozzle hole as a new reference nozzle hole other than a reference nozzle hole by an image pick-up means and comparing the nozzle hole image of the other nozzle hole picked up by the image pick-up means with a pattern image of a nozzle hole registered beforehand. SOLUTION: When a jig hold stage 306 moves to a preliminarily estimated part assemble point E, an image of a first nozzle hole of a head 2 to be positioned which is loaded on a part load jig 100 held by the jig hold stage 306 is picked up by a CCD camera 601. The nozzle hole image of the first nozzle hole of the head 2 on the part load jig 100 picked up by the CCD camera 601 is compared through pattern recognition with a reference pattern of a nozzle hole image registered beforehand to an image memory by a sub controller. Whether or not the nozzle hole image of the first nozzle hole picked up by the CCD camera 601 is a nozzle hole image of a reference nozzle hole of the head 2 is judged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for positioning an ink jet head of a printing unit used in a printer, and more particularly, to a head support for assembling the ink jet head and the ink jet head. The present invention relates to a method for positioning an ink jet head for specifying the mounting position of the ink jet head with respect to the head support when bonding and fixing with an adhesive using an intermediate holding member disposed between the ink jet head and the ink jet head.

[0002]

2. Description of the Related Art An ink jet head (hereinafter, simply referred to as "head") of a print head unit (hereinafter, simply referred to as "head unit") used in a printer, and a head support to which the head is assembled are referred to as "heads". As an assembling method for indirectly fixing using a bracket-shaped intermediate holding member disposed between the head support and the head, the head, the head support, and the intermediate holding member are each formed using an adhesive. There is an assembling method of bonding and fixing.

[0003] This assembling method by bonding is similar to the assembling method in which the head, the head support and the intermediate holding member are fixed by screws, and the head is attached to the head support by a torque at the time of screw tightening. The position may be displaced, or the fitting accuracy of the parts may vary due to the sinking of the parts, such as an assembling method in which the head, the head support and the intermediate holding member are fitted together and fixed. Without causing the head and the head support,
The head unit can be assembled at a low cost without being affected by the accuracy of the individual finishes and maintaining the correct positional relationship with each other.

However, in such a method of assembling a head unit by bonding, the presence or absence of a positional deviation at the time of bonding between the head and the head support is determined by the positional accuracy of the head with respect to the head support after bonding and fixing, that is,
The quality of the printing performance of the head unit is determined. That is, when the head and the head support are bonded,
If the head is misaligned with respect to the head support, the printing position of ink droplets ejected from the nozzle holes of the head varies due to an assembly error due to the misalignment, and a color is printed on a printed image. Displacement and distortion occur.

[0005] Therefore, in order to assemble the head to the head support with high accuracy by such an assembling method by bonding, the head, the head support, and the intermediate holding member are bonded and fixed when the head is fixed. It is necessary to maintain the positional relationship between the head and the head support with high precision in advance so that the support and the head face each other at an accurate assembly position. By the way, in the case of this type of printer head, it is necessary to keep the tolerance of the assembly position at the time of bonding to the head support within the range of the order of microns.

Accordingly, the applicant of the present invention has used the following method when the head support and the head are bonded and fixed with an adhesive by using an intermediate holding member disposed between the head support and the head. A nozzle hole at a predetermined position among a large number of nozzle holes formed in the head surface of the head is used as a reference nozzle hole for specifying the position of the head, and a direction perpendicular to the head surface of the head is determined. The reference nozzle hole is imaged by a CCD camera equipped with a solid-state imaging device (CCD), and the nozzle hole image picked up by the CCD camera is compared with a pre-registered nozzle hole pattern image. After the nozzle hole image picked up by the camera is recognized as the nozzle hole image of the reference nozzle hole, the position of the center of gravity of the image of the reference nozzle hole is calculated by the calculation unit, and the position corresponding to the head support is calculated. The position of the head is measured in the X-axis and Y-axis directions, the assembling position of the head with respect to the head support is specified, the head is positioned with respect to the head support, and then built into the CCD camera. A control / arithmetic unit calculates the position of the head in the Z-axis direction based on output data relating to the Z-axis direction defocus amount from a certain autofocus device, and based on the measurement result, the head support unit We have developed a method of assembling a head by bonding to adjust the position of the head surface and the nozzle holes with respect to the body.

In this assembling method, the nozzle hole itself formed on the head surface of the head serves as a position reference as an adjustment target when adjusting the assembling position of the head. It is possible to save the trouble of newly setting a target (alignment mark). Further, by using the nozzle hole as the adjustment target, the head assembly position is adjusted so that the nozzle hole faces the assembly reference position at the time of adjusting the assembly position of the head. Even if the outer shape or structure changes due to processing errors or design changes, the position of the nozzle hole, that is, the print position of the print image does not change, and the positioning accuracy is extremely high, about ± 3 to 4 μm. Head positioning can be realized.

[0008]

However, as described above, in a method of assembling a head unit in which a head is adhered and fixed to a head support with an adhesive via an intermediate holding member, the head support is attached to the head support. On the other hand, if the head itself is found to be defective after the head is bonded and fixed, it is difficult to replace only the head, and the head unit itself is discarded, resulting in waste. There is a defect.

Therefore, in this method of assembling a head unit by bonding, before assembling the head to the head support, an ink ejection test of the head is performed.
Whether the head itself is defective or not is inspected in advance.

[0010] However, in the head subjected to such an ejection test, there is a case where ink remains and adheres to the reference nozzle hole. The nozzle hole image of the reference nozzle hole captured by the CCD camera appears as noise, the nozzle hole image is not recognized as the nozzle hole of the head, and the position of the head in the X-axis and Y-axis directions with respect to the head support. In some cases, measurement could not be performed, and the mounting position of the head with respect to the head support could not be specified.

As described above, when the nozzle hole image picked up by the CCD camera is compared with the nozzle hole pattern image registered in advance, the nozzle hole image picked up by the CCD camera is compared with the reference nozzle image. If the hole is not recognized as a nozzle hole image, the conventional head positioning method changes the amount of illumination of the nozzle hole to be imaged by the CCD camera so as to remove noise from the nozzle hole image. Or increasing the number of types of reference pattern images as comparisons of the nozzle hole images picked up by the CCD camera to increase the recognition rate of the nozzle hole images of the reference nozzle holes picked up by the CCD camera. I was

However, as in the former case, the C
When the illumination light amount of the nozzle hole to be imaged by the CD camera is changed, the shape of the shadow of the nozzle hole image captured by the CCD camera (the shape of the nozzle hole image) is increased or decreased by increasing or decreasing the illumination light amount for the nozzle hole. Appearance) will change.

Further, as described above, even if the number of types of reference pattern images to be compared with the nozzle hole image picked up by the CCD camera is increased, the nozzle hole image picked up by the CCD camera remains In many cases, different nozzle hole images that do not correspond to the reference pattern image are obtained depending on the state of ink adhesion to the holes.

For this reason, in such a conventional method, the nozzle hole image picked up by the CCD camera is not recognized as a pattern by the reference pattern image.
There is a problem that the measurement position of the nozzle hole varies.

On the other hand, as another positioning method of the head, the outer shape of the head or an alignment mark written on the head is used as a substitute for the reference nozzle hole, and the X-axis of the head with respect to the head support is used. In addition, there is a method of specifying the position of the head with respect to the head support by measuring the position in the Y-axis direction. In this head positioning method, the outer shape of the head or the alignment mark written on the head is used. Since the head itself contains an error, the positioning accuracy of the head is ± 7 to 8 μm
There was a problem that worsened.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method and an apparatus for positioning an ink jet head capable of positioning a head with respect to a head support with high accuracy. It is to be.

[0017]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a head support for assembling an ink jet head, and the ink jet head is disposed between the head support and the ink jet head. Using the intermediate holding member arranged at the position, in bonding and fixing with an adhesive, a nozzle hole at a predetermined position among a number of nozzle holes formed in the head surface of the ink jet head, A nozzle hole image captured by the imaging unit is captured by the imaging unit as a reference nozzle hole for specifying a position, and the nozzle hole image captured by the imaging unit is compared with a reference pattern image of the nozzle hole registered in advance. Is recognized as the nozzle hole image of the reference nozzle hole, and then the position of the center of gravity of the captured image of the reference nozzle hole is calculated by the calculating means. Calculating the position of the reference nozzle hole with respect to the head support to thereby determine the mounting position of the ink jet head with respect to the head support. When comparing the hole image with the pre-registered reference pattern image of the nozzle hole, if the nozzle hole image picked up by the imaging means is not recognized as the nozzle hole image of the reference nozzle hole, the reference pattern Until a nozzle hole image recognized by the image is obtained, another nozzle hole different from the reference nozzle hole is imaged by the imaging unit as a new reference nozzle hole, and the other nozzle hole imaged by the imaging unit is captured. The nozzle hole image is compared with a pre-registered nozzle hole pattern image again. That.

According to a second aspect of the present invention, in the ink jet head positioning method of the first aspect, the other nozzle hole different from the reference nozzle hole is a nozzle hole adjacent to the reference nozzle hole. It is.

According to a third aspect of the present invention, there is provided a head support on which an ink-jet head is assembled, and the ink-jet head is bonded to an ink-jet head using an intermediate holding member disposed between the head support and the ink-jet head. In bonding and fixing, among the many nozzle holes drilled in the head surface of the inkjet head, a nozzle hole at a previously specified position is imaged by an imaging unit as a reference nozzle hole for specifying the position of the inkjet head, After the nozzle hole image picked up by the image pickup means is compared with a pre-registered reference pattern image of the nozzle hole, the nozzle hole image picked up by the image pickup means is recognized as the nozzle hole image of the reference nozzle hole. Calculating the position of the center of gravity of the captured image of the reference nozzle hole by calculation means, By performing position measurement Le holes,
In the inkjet head positioning device for specifying the mounting position of the inkjet head with respect to the head support, when comparing a nozzle hole image captured by the imaging unit with a reference pattern image of a nozzle hole registered in advance, When the nozzle hole image picked up by the image pickup means is not recognized as the nozzle hole image of the reference nozzle hole, another nozzle hole image different from the reference nozzle hole is obtained until a nozzle hole image recognized by the reference pattern image is obtained. A control for imaging the nozzle hole as a new reference nozzle hole by the imaging means, and again comparing the nozzle hole image of another nozzle hole imaged by the imaging means with the reference pattern image of the nozzle hole registered in advance. It is characterized by having arithmetic means.

In the ink jet head positioning method and apparatus, when the nozzle hole image picked up by the image pickup means is compared with the pattern image of the nozzle hole registered in advance, the nozzle hole picked up by the image pickup means is compared. When the image is not recognized as the nozzle hole image of the reference nozzle hole, another nozzle hole different from the reference nozzle hole is used as a new reference nozzle until a nozzle hole image recognized by the reference pattern image is obtained. The image is taken as the hole by the image pickup means, and the nozzle hole image of the other nozzle hole picked up by the image pickup means is compared again with the pre-registered reference pattern image of the nozzle hole. Thereby, even if the reference nozzle hole imaged by the image pickup means is filled with the ink remaining by the above-described ejection test, the nozzle hole image of the other nozzle hole is recognized as the reference nozzle hole of the head. The control / calculation means calculates the position of the center of gravity of the captured image of the reference nozzle hole, and measures the position of the reference nozzle hole with respect to the head support. Can be specified with respect to the ink jet head.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a head unit component assembling apparatus which is a print head unit of an ink jet printing type color printer will be described below. The component assembling apparatus according to the present embodiment has basically the same configuration as the “parts assembling apparatus” described in Japanese Patent Application No. 10-29350 proposed by the present application, and therefore, a detailed description thereof will be made. Is omitted.

FIG. 1 shows an appearance of a head unit 1 assembled by a head unit assembling apparatus which is a parts assembling apparatus according to the present embodiment. This head unit 1
Are four heads 2 serving as printing ink jet heads of the color printer, a head support 3 supporting the heads 2, and arranged between the head support 3 and the heads 2 to connect the two. And an intermediate holding member 4 for holding the four heads 2 on the head support 3 by being bonded and fixed as described above.

On the other hand, as shown in FIG. 1, the head support 3 is interposed via the intermediate holding member 4 so that the head surface 2d of each head 2 is exposed from the back side to the front side. A substantially vertical head holding wall 3a for holding the head 2, and a collar for supporting the head support 3 in a reciprocating manner in a direction (main scanning direction) orthogonal to the recording paper conveyance direction. A sliding bearing 3b slidably fitted to a head unit support shaft (not shown) provided on the printer main body side, and an ink supply nozzle 2a of each of the heads 2
A cartridge holding bracket 3c and the like for mounting and holding the ink cartridge on the back side of the head support 3 so that the ink cartridge is mounted to the ink cartridge (see FIG. 4) are formed.

Each head 2 of the head unit 1
Are configured to be adhesively fixed to each head holding wall 3a of the head support 3 via four intermediate holding members 4, respectively. The intermediate holding member 4 has a substantially vertical first adhesive interface formed parallel to the head holding wall 3 a of the head support 3 and a head base 2 e in which the control board of the head 2 is incorporated. It is formed of an L-shaped member having a substantially horizontal second adhesive interface formed parallel to the upper surface. The intermediate holding member 4 is
It is formed of a transparent resin body having a property of transmitting ultraviolet light (UV light) for solidifying the UV adhesive applied to each of the bonding interfaces.

FIG. 2 is a block diagram showing the overall configuration of a head unit assembling apparatus for assembling the head unit 1 configured as described above. FIG. 3 shows an example of a specific configuration of the head unit assembling apparatus. As shown in FIGS. 2 and 3, this head unit assembling apparatus is a component mounting jig for mounting components of the head unit 1 including the head 2, the head support 3, and the intermediate holding member 4. 100, the component mounting jig 100 positioned at the component setting portions A and B of the component setting stage 201 is reciprocated between the component setting portions A and B and the jig elevating portion C of the component setting stage 201. And a component mounting jig transferring mechanism 202 for transferring the component mounting jig 100 transferred to the jig elevating portion C between the component set stage 201 and the component assembly stage 301 above the component set stage 201. A jig transfer unit 200 as a jig transfer means including a component mounting jig elevating mechanism 203 for ascending and descending with the component assembling stage 30
1 and a component mounting jig gripping mechanism 302 for gripping the component mounting jig 100 raised above, and a component mounting jig gripping mechanism 302 gripping the component mounting jig 100. A component mounting jig position adjusting mechanism 303 for reciprocating between the lifting / lowering portion D and the component assembling portion E to adjust the stop position of the component mounting jig 100 on the component assembling stage 301; Component mounting jig position measuring means 3 for measuring the moving position of component mounting jig 100 reciprocated by component mounting jig position adjusting mechanism 303.
04, a component mounting jig positioning unit 300,
With the component mounting jig 100 positioned at the component assembly site E, the intermediate holding member 4 set on the component mounting jig 100 is held, and the intermediate holding member 4 is moved to a predetermined adhesive application position. Intermediate holding member holding mechanism 40 for facing
1 and the intermediate holding member holding mechanism 401 is moved to a predetermined assembly site between the head 2 and the head support 3 set on the component mounting jig 100, and Intermediate holding member position adjusting mechanism 402 for adjusting the assembling position of the held intermediate holding member 4
An adhesive applying unit 403 for applying a UV adhesive to the intermediate holding member 4 held by the intermediate holding member holding mechanism 401; and an adhesive applying unit 403 to the intermediate holding member 4 by the adhesive applying unit 403. An intermediate holding member mounting unit 400 including an adhesive application amount adjusting unit 404 for adjusting an application amount of the applied UV adhesive;
In a state where 00 is positioned at the component assembling site, head gripping means 501 for gripping the head 2 set on the component mounting jig 100 and the component mounting jig gripping mechanism 3
02, an X-axis parallel to the X-axis, Y-axes perpendicular to the X-axis, and Z-axes parallel to the Z-axis, and α having the X, Y, and Z axes as rotation centers. , Β, and γ, a head position adjustment mechanism 502 (FIG. 4) for displacing the head gripper 501 in six axial directions to adjust the position of the head 2 gripped by the head gripper 501. A reference position as a predetermined position reference based on image data of a nozzle hole image taken by a CCD camera 601 as a component position detecting means for detecting the nozzle hole 2b of the head 2 described above. Nozzle hole position measuring means 60 for measuring the position of nozzle hole 2b
2, a nozzle hole illumination light source 604 for illuminating a reference nozzle hole 2b to be detected by the CCD camera 601 through a halogen light guide 603 as illumination means,
Nozzle hole position measurement / head fixing unit 600 including a UV light source 606 for irradiating UV light to intermediate holding member 4 transferred to a predetermined assembly position via UV light guide 605, and mainly an air cylinder A sequencer (not shown) for controlling the operation of the jig transfer unit 200 and the intermediate holding member mounting unit 400 that use the above as a drive source; and the component mounting jig as shown in FIG. Operation control of the pulse motor 300M as a drive source of the positioning unit 300, image processing and measurement data of image data obtained by each measurement means such as the component mounting jig position measurement means 304 and the nozzle hole position measurement means 602, etc. Sub-controller (personal computer) for performing arithmetic processing
And a control / arithmetic unit 700 comprising the control unit 700A.

As shown in FIG. 5, the sub-controller 700A includes a microprocessor 701 as a central processing unit (CPU), a ROM in which an operation program of an operation flow of the head unit assembling apparatus and the like are written in advance. RAM for storing and storing image data, measurement data, and the like captured by the microprocessor 701
A motor driver 703 as a drive circuit for the pulse motor 300M,
A nozzle hole illumination circuit 704 for supplying a predetermined current to the halogen light guide 603; and a reference nozzle hole 2b of the head 2 imaged by the CCD camera 601.
Input binarization circuit 705 for binarizing image data of
A monitor interface 707 for displaying an image of the reference nozzle hole 2b binarized by the image input binarization circuit 705 on a monitor 706; and a nozzle hole of the reference nozzle hole 2b imaged in advance by the CCD camera 601. An image memory 708 for registering and storing a reference pattern image composed of images, and a nozzle hole image of a reference nozzle hole 2b of the head 2 taken by the CCD camera 601 from a nozzle hole image previously registered in the image memory 708. And an image processing circuit 709 for comparing with a reference pattern image.

Here, the reference pattern image to be registered in the image memory 708 includes, among the nozzle hole images of the reference nozzle holes 2b of the head 2 imaged by the CCD camera 601, the recognition rate at the time of pattern recognition. It is desirable to select the highest image by experiment or the like.

When the operation program stored in the main memory 702 of the sub-controller 700A starts, each unit described above first returns to the home position and waits. Next, the component mounting jig 10 positioned at the component setting portions A and B of the component setting stage 201 shown in FIG.
For 0, the setting operation of each component of the head unit 1 is performed by the operator.

After the components of the head unit 1 are set on the component mounting jig 100, the component mounting jig 100 moves the component mounting jig 100 to the component setting portion A (or FIG. 3) of FIG. The tool is moved from B) to the jig elevating portion C. Then, when the component mounting jig 100 is transferred to the jig elevating portion C substantially at the center of the component setting stage 201 and stopped there, the component mounting jig elevating mechanism 2
3, the component mounting jig 100 is lifted to the jig elevating portion D of the component assembly stage 301 provided above the component set stage 201, as shown in FIG.

Thereafter, the pulse motor 300M for driving the component mounting jig positioning unit 300 is turned on. The pulse motor 300M is configured to rotate the ball screw 314 forward / reverse via a reduction gear (not shown) (see FIG. 3). The ball screw 314 is screwed with a ball nut 315 having a built-in steel ball fitted into the screw groove. The ball nut 315 is connected to the jig holding table 3 of the component mounting jig holding mechanism 302 via a channel-shaped holding table bracket 316.
06.

Referring to FIG. 3, the pulse motor 300M
Is turned on and the ball screw 314 is rotated forward, the jig holding table 306 is moved to the back side of the component assembly stage 301 along the jig positioning guide rail 305 of the component assembly stage 301. . The movement of the jig holding table 306 causes the component mounting jig 100 held by the jig holding table 306 to move to the component assembling stage 30.
The jig is moved from the jig elevating portion D to the component assembling portion E.

The movement position of the jig holding table 306 is determined by measuring the amount of movement of the linear scale 320 fixed on the jig holding table 306 by a scale measuring unit 321 fixed on the component assembly stage 301. , The scale measuring unit 32
1, the sub-controller 700A
Thus, the pulse motor 300M is controlled very accurately by turning on / off.

Thus, the jig holding table 306
Is moved to the component assembling site E assumed in advance, first, the jig holding table 306 is moved by the CCD camera 601.
An image of the first nozzle hole 2b-1 (see FIG. 6) of the head 2 to be positioned on the component mounting jig 100 gripped by the camera is taken. Then, a nozzle hole image of the first nozzle hole 2b-1 of the head 2 to be positioned on the component mounting jig 100, which is captured by the CCD camera 601, is stored in the image memory 7 by the sub controller 700A.
The reference nozzle image of the first nozzle hole 2b-1 captured by the CCD camera 601 is compared with a reference pattern image including a nozzle hole image registered in advance in the head nozzle 08, and the reference nozzle image of the head 2 is obtained. It is determined whether the image is the nozzle hole image of 2b.

FIG. 7 shows an example of a flowchart of a head positioning program for positioning the head 2 at a predetermined assembly position with respect to the head support based on the position of the nozzle hole 2b imaged by the CCD camera 601. Show. In FIG. 7, when the head positioning program starts, first, the position of the first nozzle hole 2b-1 is determined based on the nozzle hole image of the first nozzle hole 2b-1 captured by the CCD camera 601. Is measured by the nozzle hole position measuring means 602 (step S1).

Here, if the position of the first nozzle hole 2b-1 can be measured in step S1, that is, if "YES" is determined in step S2, the first nozzle Based on the nozzle hole image of the hole 2b-1, the microprocessor 701 calculates the current position of the first nozzle hole 2b-1 (Step S3). Then, based on the calculation result of the current position of the first nozzle hole 2b-1, the first nozzle hole 2b-
1 and the head 2 with respect to the head support 3
The deviation amount from the target position at the time of assembling is calculated by the microprocessor 701 (step S4).

Next, the first nozzle hole 2b-1
It is determined whether or not the amount of deviation between the current position and the target position at the time of assembling the head 2 with respect to the head support 3 is within a standard (within an appropriate error range) (step S5). If it is determined in step S5 that the deviation amount is within the standard, the head positioning program is stopped, and the head 2 is moved to the head support 3.
Is positioned at an appropriate assembly position. Here, if it is determined that the deviation amount is not within the standard, that is, if “NO” is determined in step S5, as shown in step S6, the target position is determined based on the deviation amount. The movement amount of the head 2 is calculated by the microprocessor 701, and as shown in step S7,
After moving the head position adjusting mechanism 502 in the predetermined direction by the moving amount, the measuring operation in step S1 is executed again.

On the other hand, in the step S1, the first
When the position of the nozzle hole 2b-1 cannot be measured, for example, if the above-described ink ejection test ink remains in the first nozzle hole 2b-1,
01, the nozzle hole image of the first nozzle hole 2b-1 is not recognized by the reference pattern image registered in advance in the image memory 708, and the determination of “NO” is made in step S2. Is made.

Therefore, in this case, for example, as shown in FIG. 6, the second nozzle hole 2b-2 adjacent to the first nozzle hole 2b-1 of the head 2 is connected to the CCD camera 601. , And the second nozzle hole 2b-2 nozzle hole image is obtained by the sub-controller 700A.
The second nozzle hole 2b-2 nozzle hole image is compared with a reference pattern image composed of nozzle hole images registered in advance in the image memory 708 by pattern recognition. It is determined whether the image is an image.

Then, based on the nozzle hole image of the second nozzle hole 2b-2 captured by the CCD camera 601, the position of the second nozzle hole 2b-2 is determined by the nozzle hole position measuring means 602. Measured (step S
8). Here, if the position of the second nozzle hole 2b-2 can be measured in step S8, that is, if “YES” is determined in step S9, the second nozzle hole 2b-2 Based on the second nozzle hole image, the microprocessor 701 calculates the current position of the second nozzle hole 2b-2 (step S).
10).

Next, in step S11, the above-described target position for assembling the first nozzle hole 2b-1 is corrected to the target position for assembling the second nozzle hole 2b-2. After the correction of the target position, the current position of the second nozzle hole 2b-2 and the head 2 with respect to the head support 3 are calculated based on the calculation result of the current position of the second nozzle hole 2b-2. The amount of deviation from the target position at the time of assembly after the correction is calculated by the microprocessor 701 (step S12).

Next, the second nozzle hole 2b-2
It is determined whether or not the amount of deviation between the current position and the corrected target position at the time of assembling the head 2 with respect to the head support 3 is within a standard (within an appropriate error range) (step S1).
3). If it is determined in step S13 that the deviation amount is within the standard, in step S14, the target position for assembling the second nozzle hole 2b-2 is changed to the first nozzle hole 2b. After returning to the target position at the time of assembly for -1, the head positioning program is stopped, and the head 2 is moved with respect to the head support 3.
It is positioned at an appropriate assembly position.

Here, if it is determined that the deviation amount is not within the standard, that is, if “NO” is determined in step S13, as shown in step S15, based on the deviation amount, The moving amount of the head 2 to the target position for the second nozzle hole 2b-2 is calculated by the microprocessor 701, and the head position adjusting mechanism 502 is moved by the moving amount as shown in step S16. After moving in the predetermined direction, the measurement operation in step S8 is executed again.

Further, in the step S8, the second
When it is impossible to measure the position of the nozzle hole 2b-2, for example, the ink for the above-described ink ejection test remains in the second nozzle hole 2b-2. If the detected nozzle hole image of the second nozzle hole 2b-2 is not recognized by the reference pattern image registered in advance in the image memory 708, "NO" is determined in step S9. .

In this case, as shown in FIG. 6, a third nozzle hole 2b-3 adjacent to the second nozzle hole 2b-2 of the head 2 is imaged by the CCD camera 601. The image of the third nozzle hole 2b-3 is stored in the image memory 7 by the sub controller 700A.
The third nozzle hole 2b-3 nozzle hole image is a nozzle hole image of the reference nozzle hole 2b of the head 2 as compared with a reference pattern image consisting of nozzle hole images registered in advance in 08 by pattern recognition. It is determined whether or not.

Then, based on the nozzle hole image of the third nozzle hole 2b-3 imaged by the CCD camera 601, the position of the third nozzle hole 2b-3 is determined by the nozzle hole position measuring means 602. (Step S17). Here, when the position of the third nozzle hole 2b-3 can be measured in step S17,
As in the case of the second nozzle hole 2b-2 described above, the current position of the third nozzle hole 2b-3 is calculated, and
After the target position for the nozzle hole 2b-1 is corrected to the target position for the third nozzle hole 2b-3, based on the calculation result of the current position of the third nozzle hole 2b-3, The third
The current position of the nozzle hole 2b-3 and the head support 3
Is calculated by the microprocessor 701.

Then, the third nozzle hole 2b-3
It is determined whether the deviation between the current position and the corrected target position when the head 2 is assembled to the head support 3 is within a standard (within an appropriate error range), and the deviation is within the standard. When it is determined that is the same as in step S14,
After returning the target position at the time of assembly for the third nozzle hole 2b-3 to the target position at the time of assembly for the first nozzle hole 2b-1, the head positioning program is stopped.

If it is determined that the displacement amount of the third nozzle hole 2b-3 is not within the standard, step S1
5 and step S16, based on the amount of displacement of the third nozzle hole 2b-3, the third nozzle hole 2b
The microprocessor 701 calculates the amount of movement of the head 2 to the target position for -3, and after moving the head position adjusting mechanism 502 in the predetermined direction by the amount of movement, the measuring operation of step S17 is performed. Is executed again.

As described above, in the component assembling apparatus according to the present embodiment, the nozzle hole image of the nozzle hole 2b of the head 2 captured by the CCD camera 601 and the reference pattern image of the nozzle hole registered in advance are used. In comparison, when the nozzle hole image of the first nozzle hole 2b-1 of the head 2 captured by the CCD camera 601 is not recognized as the nozzle hole image of the reference nozzle hole,
Until a nozzle hole image recognized by the reference pattern image is obtained, other second, third,... Nozzle holes 2b-2, 2b-3,... Different from the first nozzle hole 2b-1, The CCD camera 601 captures an image as a new reference nozzle hole, and the nozzle hole image of the other nozzle hole captured by the CCD camera 601 is compared again with the reference pattern image of the nozzle hole registered in advance. Even if the reference nozzle hole is filled with the ink remaining in the ejection test, the nozzle hole image of the other nozzle hole can be recognized as the reference nozzle hole of the head.

[0049]

According to the first to third aspects of the present invention, even if ink remains in the reference nozzle hole imaged by the image pickup means and is filled with ink by the ink ejection test, it is recognized by the reference pattern image. Until the nozzle hole image is obtained
Another nozzle hole different from the reference nozzle hole is imaged as a new reference nozzle hole by the imaging means, and the nozzle hole image of the other nozzle hole can be recognized as the reference nozzle hole of the head. Therefore, the control / calculation means calculates the position of the center of gravity of the captured image of the reference nozzle hole, and measures the position of the reference nozzle hole with respect to the head support. There is an excellent effect that the assembling position can be specified accurately.

[Brief description of the drawings]

FIG. 1 is an exemplary perspective view showing the appearance of a head unit assembled by a head unit assembling apparatus according to an embodiment;

FIG. 2 is a block diagram showing an overall configuration of the head unit assembling apparatus.

FIG. 3 is a schematic front view showing the overall configuration of the head unit assembling apparatus.

FIG. 4 is a conceptual diagram of a sub-controller that detects a mounting position of the head with respect to a head support of the head unit.

FIG. 5 is a block diagram showing a schematic configuration of the sub-controller.

FIG. 6 is a schematic diagram showing an example of a nozzle hole image of a nozzle hole of the head taken by a CCD camera of the head unit assembling apparatus.

FIG. 7 is a flowchart showing an example of a head positioning program for positioning the head at a predetermined assembly position with respect to the head support based on the positions of nozzle holes imaged by the CCD camera.

[Explanation of symbols]

 Reference Signs List 1 head unit 2 inkjet head 2b nozzle hole 2b-1 first nozzle hole 2b-2 second nozzle hole 2b-3 third nozzle hole 2d head surface 3 head support 4 intermediate holding member 100 component mounting jig 201 Component setting stage 300 Component mounting jig positioning unit 300M Pulse motor 301 Component assembly stage 400 Intermediate holding member mounting unit 403 Adhesive applying means 500 Head position adjusting unit 600 Nozzle hole position measurement / head fixing unit 601 CCD camera 602 Nozzle hole position measurement Means 603 Halogen light guide 604 Nozzle hole illumination light source 700 Control / calculation device 700A Sub-controller 701 Microprocessor 702 Main memory 703 Motor driver 704 Nozzle illumination circuit 705 Image input 2 Circuit 706 monitors 707 monitor interface 708 an image memory 709 the image processing circuit A, B parts set site E component assembly sites

Claims (3)

[Claims] 1. A method according to claim 1, further comprising: fixing a head support on which the inkjet head is assembled, and the inkjet head with an adhesive using an intermediate holding member disposed between the head support and the inkjet head. An image pickup unit picks up an image of a nozzle hole at a predetermined position among a number of nozzle holes formed in the head surface of the ink jet head as a reference nozzle hole for specifying the position of the ink jet head, and picks up an image by the image pickup unit. The registered nozzle hole image is compared with a pre-registered reference pattern image of the nozzle hole, and after the nozzle hole image picked up by the imaging means is recognized as the nozzle hole image of the reference nozzle hole, the reference nozzle hole The position of the reference nozzle hole with respect to the head support is measured by calculating the center of gravity position of the captured image of Thus, in the method of positioning the ink jet head for specifying the mounting position of the ink jet head with respect to the head support, the nozzle hole image picked up by the image pickup unit is compared with a reference pattern image of the nozzle hole registered in advance. At that time,
When the nozzle hole image picked up by the image pickup means is not recognized as the nozzle hole image of the reference nozzle hole,
Until a nozzle hole image recognized by the reference pattern image is obtained, another nozzle hole different from the reference nozzle hole,
Imaged by the imaging means as a new reference nozzle hole,
A method of positioning an ink jet head, comprising: again comparing a nozzle hole image of another nozzle hole captured by the imaging unit with a pattern image of a nozzle hole registered in advance. 2. The ink jet head positioning method according to claim 1, wherein another nozzle hole different from said reference nozzle hole is a nozzle hole adjacent to said reference nozzle hole. 3. The method according to claim 1, wherein the head support and the inkjet head are assembled and fixed with an adhesive using an intermediate holding member disposed between the head support and the inkjet head. An image pickup unit picks up an image of a nozzle hole at a predetermined position among a number of nozzle holes formed in the head surface of the ink jet head as a reference nozzle hole for specifying the position of the ink jet head, and picks up an image by the image pickup unit. The registered nozzle hole image is compared with a pre-registered reference pattern image of the nozzle hole, and after the nozzle hole image picked up by the imaging means is recognized as the nozzle hole image of the reference nozzle hole, the reference nozzle hole The position of the reference nozzle hole with respect to the head support is measured by calculating the center of gravity position of the captured image of Thus, in the inkjet head positioning device for specifying the mounting position of the inkjet head with respect to the head support, the nozzle hole image captured by the imaging unit is compared with a reference pattern image of the nozzle hole registered in advance. At that time,
When the nozzle hole image picked up by the image pickup means is not recognized as the nozzle hole image of the reference nozzle hole,
Until a nozzle hole image recognized by the reference pattern image is obtained, another nozzle hole different from the reference nozzle hole,
Imaged by the imaging means as a new reference nozzle hole,
An ink jet head positioning apparatus, comprising: a control / calculation means for again comparing a nozzle hole image of another nozzle hole imaged by the imaging means with a reference pattern image of a nozzle hole registered in advance.