JP2021088108A - Printing device - Google Patents

Abstract

To provide a printing device, which is configured to accurately perform printing on a work-piece having a three-dimensional curve.SOLUTION: A work-piece driving unit 30 has a Y-axis direct-acting mechanism 31, a Z-axis direct-acting mechanism 32, an A-axis rotating mechanism 35, a B-axis rotating mechanism 36 and a C-axis rotating mechanism 37. The work-piece driving unit 30 changes a posture of a work-piece W to adjust a distance between a surface of the work-piece W and a head part 21. A printing unit 10 discharges droplets 25 to the surface of the work-piece W.SELECTED DRAWING: Figure 2

Description

The present invention relates to a printing apparatus.

Conventionally, a printing device that prints on a workpiece having a curved surface by using an inkjet has been known (see, for example, Patent Document 1).

Patent Document 1 discloses a configuration in which an ink droplet is ejected by tilting a nozzle row in a sub-scanning direction with respect to a side surface of a tubular workpiece whose axial direction is the main scanning direction of the inkjet head. There is.

Japanese Patent No. 6426038

By the way, in the invention of Patent Document 1, the cross-sectional shape of the printable work is limited to that of a tubular body. Therefore, there has been a demand for a printing apparatus capable of printing with high accuracy not only on a tubular work but also on a work having an arbitrary three-dimensional curved surface.

The present invention has been made in view of this point, and an object of the present invention is to enable accurate printing on a work having a three-dimensional curved surface.

The present invention is intended for a printing apparatus that prints a predetermined image by ejecting droplets onto a workpiece having a curved surface, and has taken the following solutions.

That is, the first invention comprises a printing unit having a head portion for ejecting droplets on the surface of the work.
A work drive unit that changes the posture of the work to adjust the distance between the surface of the work and the head portion is provided.
The work drive unit has a drive mechanism of at least 5 axes.
At least three of the five-axis drive mechanisms are composed of rotating mechanisms.

In the first invention, the work drive unit has a drive mechanism having at least five axes, of which at least three axes are configured by a rotation mechanism.

As a result, the adjustment range of the posture of the work can be widened, the posture adjustment according to the curved surface of the work can be speeded up, and the work can be printed with high accuracy.

The second invention is the first invention.
The printing unit has a drive mechanism of at least one axis.

In the second invention, the printing unit has a drive mechanism of at least one axis. Thereby, for example, printing with a high degree of freedom can be performed even on a work having a concave surface or a convex surface.

The third invention is the second invention.
The printing unit has a main scanning linear motion mechanism that moves the head portion in the main scanning direction, and a uniaxial rotation mechanism.

In the third invention, the printing unit has a main scanning linear motion mechanism and a rotation mechanism. As a result, the nozzle position of the head portion with respect to the work can be finely adjusted by the rotation mechanism while moving the head portion in the main scanning direction.

For example, by setting a row of a plurality of nozzles arranged in a row along the sub-scanning direction of the head portion at an angle with respect to the main scanning direction, the pitch between the nozzles can be reduced and the printing resolution can be improved. Can be enhanced.

Further, the ink landing accuracy can be improved by rotating the row of nozzles of the head portion by 90 ° with respect to the main scanning direction and changing the printing direction.

The fourth invention is the second invention.
The printing unit includes a plurality of the head portions, a main scanning linear motion mechanism for moving the plurality of head portions in the main scanning direction, and a sub-order in which at least one of the plurality of head portions intersects the main scanning direction. It is equipped with a sub-scanning linear motion mechanism that moves in the scanning direction.

In the fourth invention, at least one of the plurality of head portions is movable in the sub-scanning direction. In this way, by printing only the head portion of the color to be printed close to the work, it is possible to prevent other head portions from interfering with the work. As a result, the degree of freedom in the posture adjustment operation of the work can be increased.

The fifth invention is the second invention.
The printing unit includes a plurality of the head portions, a main scanning linear motion mechanism for moving the plurality of head portions in the main scanning direction, and advancing / retreating of at least one of the plurality of head portions with respect to the work. It has a linear motion mechanism.

In the fifth invention, at least one of the plurality of head portions is moved forward and backward with respect to the work. In this way, by printing only the head portion of the color to be printed close to the work, it is possible to prevent other head portions from interfering with the work. As a result, the degree of freedom in the posture adjustment operation of the work can be increased.

The sixth invention is based on any one of the first to fifth inventions.
The work drive unit is
A Y-axis linear motion mechanism that moves the work in the Y direction orthogonal to the X direction, which is the main scanning direction,
A Z-axis linear motion mechanism provided in the Y-axis linear motion mechanism and moving the work in the Z direction orthogonal to the X direction and the Y direction.
An A-axis rotation mechanism provided in the Z-axis linear motion mechanism and rotating the work around the A-axis extending in the X direction.
A B-axis rotation mechanism provided in the A-axis rotation mechanism and rotating the work around the B-axis extending in the Y direction, and a B-axis rotation mechanism.
It has a C-axis rotation mechanism provided in the B-axis rotation mechanism and rotating the work around the C-axis extending in the Z direction.

In the sixth invention, the work drive unit is composed of a two-axis linear motion mechanism and a three-axis rotation mechanism. As a result, the adjustment range of the posture of the work can be widened, the posture adjustment according to the curved surface of the work can be speeded up, and the work can be printed with high accuracy.

The seventh invention is the invention of any one of the first to fifth inventions.
The work drive unit is
A Y-axis linear motion mechanism that moves the work in the Y direction orthogonal to the X direction, which is the main scanning direction,
A C-axis rotation mechanism provided in the Y-axis linear motion mechanism and rotating the work around the C-axis extending in the X-direction and the Z-direction orthogonal to the Y-direction.
A Z-axis linear motion mechanism provided in the C-axis rotation mechanism to move the work in the Z direction, and a Z-axis linear motion mechanism.
An A-axis rotation mechanism provided in the Z-axis linear motion mechanism and rotating the work around the A-axis extending in the X direction.
It has a B-axis rotation mechanism provided in the A-axis rotation mechanism and rotating the work around the B-axis extending in the Y direction.

In the seventh invention, the work drive unit is composed of a two-axis linear motion mechanism and a three-axis rotation mechanism. As a result, the adjustment range of the posture of the work can be widened, the posture adjustment according to the curved surface of the work can be speeded up, and the work can be printed with high accuracy.

According to the present invention, it is possible to print with high accuracy on a work having a three-dimensional curved surface.

It is a front view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 1. It is a side view which shows the schematic structure of the printing apparatus. It is a top view which shows the schematic structure of the printing apparatus. It is a top view which shows the structure of the inkjet part. It is a top view which shows the state which the head part was tilted with respect to the printing direction. It is a top view explaining the direction of the head part at the time of printing a frame-shaped image. It is a top view which shows another structure of the inkjet part. It is a top view which shows another structure of the inkjet part. It is a top view which shows another schematic structure of a printing apparatus. It is a figure which shows the distance between the nozzle of a head part and the surface of a work. It is a figure which shows the distance between the nozzle of a head part and the surface of a work when the posture of a work is changed. It is a perspective view which shows the relationship between a work and a coating line. It is a side view which shows the state which the nozzle is opposed to the print coordinate of a work. It is a side view which shows the state which the nozzle is opposed to the next print coordinate of a work. It is a perspective view which shows the 1st region in the curved surface of a work. It is a perspective view which shows the 1st region and the 2nd region on the curved surface of a work. It is a front view which shows the schematic structure of the printing apparatus which concerns on Embodiment 2. It is a front view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 3. It is a front view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 4. It is a front view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 5. It is a side view which shows the schematic structure of the printing apparatus. It is a side view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 6. It is a side view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 7. It is a side view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 8. It is a side view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 9. It is a side view which shows the schematic structure of the printing apparatus which concerns on this Embodiment 10.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is essentially merely an example and is not intended to limit the present invention, its application or its use.

<< Embodiment 1 >>
As shown in FIGS. 1 to 3, the printing apparatus 1 prints a predetermined image by ejecting droplets onto the work W having a three-dimensional curved surface. The work W is made of, for example, a resin molded product.

The printing device 1 includes a printing unit 10, a work drive unit 30, and a control unit 15. The printing device 1 has a gantry 2 and a gate-shaped gantry 3 erected from the gantry 2. The work drive unit 30 is provided on the gantry 2. The gantry 3 is provided with a printing unit 10.

<Printing unit>
The printing unit 10 is arranged above the printing surface of the work W. The printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 (main scanning linear motion mechanism) and a C'axis rotation mechanism 38.

The X-axis linear motion mechanism 11 is attached to the gantry 3. The C'axis rotation mechanism 38 is attached to the X-axis linear motion mechanism 11. The inkjet unit 20 is attached to the X-axis linear motion mechanism 11 via the C'axis rotation mechanism 38. The C'axis rotation mechanism 38 rotates the head portion 21 of the inkjet unit 20 in the horizontal direction around the C'axis extending in the vertical direction.

The inkjet unit 20 is moved in the main scanning direction (left-right direction in FIG. 1) by the X-axis linear motion mechanism 11. The inkjet unit 20 prints an image on the surface of the work W by ejecting the droplet 25 toward the work W while moving in the main scanning direction. At this time, by moving the work W relative to the inkjet unit 20 by the work drive unit 30, the image can be printed in the sub-scanning direction (horizontal direction in FIG. 2) orthogonal to the main scanning direction.

As shown in FIG. 4, the inkjet unit 20 has a head unit 21. The head portion 21 is provided with four nozzle rows corresponding to four colors of cyan (C), magenta (M), yellow (Y), and black (K).

The nozzle row has a plurality of nozzles 22 arranged in a row along the sub-scanning direction. Here, the pitch P1 between the adjacent nozzles 22 is set to, for example, 150 to 1200 dpi. The nozzles 22 may be arranged side by side in two or more rows along the sub-scanning direction.

In the example shown in FIG. 4, in order to explain the pitch between the nozzles 22 in an easy-to-understand manner, a plurality of nozzles 22 in the four nozzle rows are arranged side by side at the same position when viewed from the printing direction. It is not limited to. For example, the plurality of nozzles 22 in the four nozzle rows may be arranged so as not to overlap each other when viewed from the printing direction.

The inkjet unit 20 is a piezo type, and ejects a predetermined amount of droplets 25 from the nozzle 22 vertically downward in response to a drive signal supplied from the control unit 15.

Here, as shown in FIG. 5, when printing on the work W, the head portion 21 may be tilted obliquely with respect to the printing direction by the C'axis rotation mechanism 38. As a result, the pitch P2 between the nozzles 22 in the nozzle row becomes smaller than the pitch P1 (see FIG. 4) before the head portion 21 is tilted.

In this way, the print resolution can be increased by setting the head portion 21 in an obliquely tilted posture with respect to the printing direction.

Further, as shown in FIG. 6, when printing a rectangular frame-shaped image (described by a virtual line in FIG. 6) on the work W, the head portion 21 is subjected to a nozzle row by the C'axis rotation mechanism 38. The posture is such that the printing direction is orthogonal to the printing direction.

Specifically, when printing from the upper left corner to the right side in FIG. 6, the head portion 21 is moved to the upper right corner in a posture in which the nozzle row extends in the vertical direction in FIG.

After the head portion 21 reaches the upper right corner in FIG. 6, the head portion 21 is rotated 90 ° clockwise. As a result, the head portion 21 is in a posture in which the nozzle row extends in the left-right direction in FIG. After that, the head portion 21 is moved from the upper right corner portion to the lower right corner portion in FIG.

Then, the head portion 21 that has reached the lower right corner in FIG. 6 is rotated by 90 ° in the clockwise direction so that the nozzle row extends in the vertical direction in FIG. After that, the head portion 21 is moved from the lower right corner to the left in FIG.

Then, the head portion 21 that has reached the lower left corner in FIG. 6 is rotated by 90 ° in the clockwise direction so that the nozzle row extends in the left-right direction in FIG. After that, the head portion 21 is moved upward from the lower left corner portion in FIG. 6 to complete a rectangular frame-shaped image.

In this way, the nozzle row of the head portion 21 is rotated by 90 ° with respect to the main scanning direction to change the printing direction, so that the ink landing accuracy can be improved.

Although the inkjet unit 20 shown in FIG. 4 is provided with one head unit 21, a plurality of head units 21 may be provided. In this case, not all the head portions 21 need to have different colors, and there may be a plurality of the same colors.

Further, although the inkjet unit 20 is provided with only the head unit 21 as a single unit, the inkjet unit 20 is not limited to this form. For example, as shown in FIG. 7, the inkjet unit 20 may have a head unit 21 and a curing unit 23.

Specifically, the inkjet unit 20 has a head unit 21 and two cured units 23 arranged on both sides of the head unit 21 in the printing direction (left-right direction in FIG. 7). The inkjet unit 20 may have a head unit 21 and one curing unit 23 (see FIG. 8).

The curing portion 23 cures ink or paint. The cured portion 23 is selected according to the type of ink or paint to be applied. For example, as the curing portion 23, an ultraviolet light source such as a metal halide lamp or UV-LED, an infrared light source such as a halogen lamp or an infrared laser diode, an infrared light source such as an infrared laser, a heat source by a heater, or the like can be used.

Here, since the two curing portions 23 are arranged on both sides of the head portion 21 in the printing direction, the two curing portions 23 are used to cure the droplet 25 during the reciprocating operation of the inkjet unit 20. be able to.

Further, as shown in FIG. 8, the inkjet unit 20 may have a head unit 21 and a distance measuring unit 24.

The distance measuring unit 24 measures the distance between the inkjet unit 20 and the work W. The distance measuring unit 24 is selected according to the type of material constituting the work W. For example, a contact-type probe can be used as the distance measuring unit 24. In addition, a non-contact type that measures the distance based on the time from when the work W is irradiated with light such as a laser displacement meter, ultrasonic displacement meter, or LED until it returns to the light receiving element (not shown) is used. be able to.

Here, before printing by ejecting the droplet 25 onto the work W, the distance measuring unit 24 measures the distance between the work W and the printing unit 10.

Specifically, when the work W is composed of a resin molded product, a dimensional difference of ± 1 mm or more is generated with respect to the design CAD data of the product.

Therefore, by measuring the distance between the inkjet unit 20 and the work W in advance, the printing gap is such that the ink jet unit 20 and the work W do not collide with each other during printing and the droplets reach the distance reliably. Can be set appropriately.

The distance measuring unit 24 may measure the shape of the work W and convert it into surface data of the work W based on the measurement data. As a result, the surface data of the work W can be used for printing. Further, the print gap may be changed by measuring only the representative points of the area to be printed.

Such work may be acquired for the entire number of parts to be printed, or may be extracted. It should be noted that such a procedure for distance measurement does not need to be particularly performed as long as the material has excellent dimensional stability.

The inkjet unit 20 may have a head unit 21, a curing unit 23, and a distance measuring unit 24.

Here, the ink or paint of each color is composed of a material that is cured by ultraviolet rays (UV). The primer, clear, etc. may be of the ultraviolet type or the solvent type. Further, the metallic material may be an ultraviolet type or a solvent type.

The ink or paint of each color is preferably cured by ultraviolet rays (UV), but may be a solvent type.

<Work drive unit>
As shown in FIGS. 1 to 3, a fixing jig 40 is attached to the tip of the work drive unit 30. The work W is fixed to the fixing jig 40. The work drive unit 30 conveys the work W fixed to the fixing jig 40 below the printing unit 10.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

The Y-axis linear motion mechanism 31 is mounted on the gantry 2. The Y-axis linear motion mechanism 31 moves the work W in the sub-scanning direction.

The Z-axis linear motion mechanism 32 is attached to the Y-axis linear motion mechanism 31. The Z-axis linear motion mechanism 32 moves the work W in the vertical direction.

The A-axis rotation mechanism 35 is attached to the Z-axis linear motion mechanism 32. The A-axis rotation mechanism 35 rotates the work W around the A-axis extending in the X direction.

The B-axis rotation mechanism 36 is attached to the A-axis rotation mechanism 35 via a box-shaped holding body 42 having an opening at the upper side. The B-axis rotation mechanism 36 rotates the work W around the B-axis extending in the Y direction.

The C-axis rotation mechanism 37 is attached to the B-axis rotation mechanism 36 via the support arm 41. A fixing jig 40 is attached to the C-axis rotation mechanism 37. The C-axis rotation mechanism 37 rotates the work W around the C-axis extending in the Z direction.

The work drive unit 30 operates the Y-axis linear motion mechanism 31, the Z-axis linear motion mechanism 32, the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37 to move the work drive unit 30 below the inkjet unit 20. Move the work W. At this time, the position and posture of the work W are adjusted by the work drive unit 30.

Here, as shown in FIG. 3, the holding body 42 holding the work W via the B-axis rotation mechanism 36 and the C-axis rotation mechanism 37 is cantilevered and supported by the A-axis rotation mechanism 35. Therefore, particularly when the weight of the work W is large, the stress applied to the A-axis rotation mechanism 35 becomes large.

Therefore, as shown in FIG. 9, the Y-axis linear motion mechanism 31, the Z-axis linear motion mechanism 32, and the A-axis rotation mechanism 35 are arranged on the left and right sides of the holding body 42, respectively, to support the holding body 42 at both ends. You may try to do it.

As a result, the stress applied to the A-axis rotation mechanism 35 can be dispersed, and the work W can be smoothly rotated.

<Control unit>
As shown in FIG. 1, the control unit 15 is composed of, for example, a personal computer or a PLC (Programmable Logic Controller). The control unit 15 controls the operations of the printing unit 10 and the work drive unit 30.

The control unit 15 controls the printing unit 10 to operate the X-axis linear motion mechanism 11 and the C'axis rotation mechanism 38, and controls to eject the droplet 25 from the head unit 21.

The control unit 15 is for operating the Y-axis linear motion mechanism 31, the Z-axis linear motion mechanism 32, the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37 with respect to the work drive unit 30. Take control.

<Posture and orientation of the workpiece when printing>
As shown in FIG. 10, the intersection of the perpendicular line drawn from the nozzle 22a near the center toward the surface of the work W and the surface of the work W among the plurality of nozzles 22 of the inkjet unit 20 is defined as an intersection 75. ..

The point where the vertical line drawn from the intersection of the center line in the X direction and the center line in the Y direction of the head portion 21 toward the surface of the work W and the surface of the work W intersect is defined as the intersection. It may be the intersection 75.

The tangent line 76 with respect to the surface of the work W at the intersection 75 is parallel to the lower surface of the inkjet unit 20 (the surface on which the nozzle 22 is arranged). Here, let D be the distance between the nozzle 22 and the surface of the work W.

The control unit 15 drives the Z-axis linear motion mechanism 32, the Y-axis linear motion mechanism 31, the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37 to drive the nozzle 22a and the work near the center. The posture and orientation of the work W are adjusted so that the distance D1 from the intersection 75 on the surface of W is substantially constant.

Here, the distance D1 is set to an arbitrary value in the range of 0.3 to 7 mm. As described above, this range is a range in which the droplet 25 can be stably applied. The curved surface of the work W, the printing accuracy, and the like may be changed as necessary.

By the way, even if the distance D1 between the nozzle 22a near the center and the intersection 75 on the surface of the work W is made substantially constant, there are places having different curvatures on the surface of the work W, so that the nozzle 22 and the surface of the work W The distance will change.

Then, in the portion where the distance D between the nozzle 22 and the work W is longer than a predetermined value, the time for the droplet 25 to reach the work W becomes longer, so that the droplet 25 is more susceptible to the influence of the surrounding air flow. Therefore, the landing position of the droplet 25 shifts, causing phenomena such as bleeding, blurring, and color shift. That is, if the droplets 25 are not accurately arranged at predetermined positions on the three-dimensional curved surface on the surface of the work W, the printed image may have low image quality.

Specifically, the distance between the leftmost nozzle 22 and the work W in FIG. 11 is longer than the distance between the leftmost nozzle 22 and the work W in FIG. Therefore, in order to arrange the droplets 25 with high accuracy, it is necessary to change the coating width of the nozzle row according to the curvature of the surface of the work W.

The control unit 15 sets the coating area according to the following procedure based on the data such as CAD. After that, the inkjet unit 20 coats the droplet 25 on the surface of the work W for each coating region.

Specifically, as shown in FIG. 12, a coating line 50 is set on the surface of the work W. The coating line 50 is preferably set at a portion of the surface of the work W that is close to the plane having the smallest curvature.

Next, as shown in FIG. 13, a plurality of print coordinates 52 divided into equal pitches 51 are set on the coating line 50. The print coordinates 52 are calculated from the CAD data according to the required print resolution. For example, the print coordinates 52 are preferably set at the pitch of the print resolution. Further, the print coordinates 52 may be set at a pitch that is an integral multiple of the print resolution.

Then, the inkjet unit 20 is moved relative to the work W on the coating line 50. Specifically, the inkjet unit 20 is relative to the work W so that the perpendicular line drawn from the nozzle 22a near the center of the head unit 21 of the inkjet unit 20 toward the surface of the work W coincides with the print coordinates 52. Move to. At this time, the posture and orientation of the work W are adjusted so that the distance D between the nozzle 22 and the surface of the work W is substantially constant.

Next, as shown in FIG. 14, the inclination of the line segment 53 connecting the print coordinate 52 facing the nozzle 22 and the next print coordinate 52 is in the vicinity of 0 (parallel and horizontal to the nozzle surface). As such, the work W is moved and rotated.

As a result, the work W changes from the state shown in FIG. 13 to the state shown in FIG. In FIGS. 13 and 14, the tangent line of the curved surface at each print coordinate 52 and the nozzle surface are parallel. Here, the tangent line of the curved surface at the print coordinates 52 is perpendicular to the coating line 50.

Next, the inkjet unit 20 is moved relative to all the print coordinates 52 on the coating line 50. Then, among the plurality of nozzles 22, only the nozzles 22 in which the distance D between the nozzles 22 and the surface of the work W is a certain range D2 at the print coordinates 52 are selected (see FIGS. 10 and 11). For example, only the nozzles 22 having a distance D of 5 mm or less need to be selected.

As shown in FIG. 15, the region that can be applied by the selected nozzle 22 is defined as the first region 55. The first region 55 is set to a region sandwiched between two lines parallel to the coating line 50.

After setting the first region 55, the next coating line 54 is set at a position adjacent to the first region 55. Then, the second region 56 is set by repeating the above-mentioned process (see FIG. 16).

Such a process is repeated for the required coating area of the work W. After that, the droplet 25 is applied by the inkjet unit 20 for each set area.

Here, if the curvature of the surface of each region is different, the width of the region is different and the number of nozzles 22 to be selected is also different. Therefore, by setting the distance D between the nozzle 22 and the surface of the work W within a certain range, the droplet 25 can be applied with high accuracy.

Further, when the coating area of the work W is divided into a plurality of areas, it is preferable that no gap is formed between the areas. For example, if the coating line 54 is the end of the first region 55, no gap is formed between the first region 55 and the second region 56. However, even when a gap is generated, another region may be separately provided in the portion where the gap is generated, and the droplet 25 may be applied.

When setting the distance D between the nozzle 22 and the surface of the work W, the nozzle 22a near the center is used as a reference, but another nozzle 22 may be used as a reference. In particular, the nozzles 22 arranged at both ends of the nozzle row may be used as a reference in order to set the area without gaps or to set a wide area. Further, different nozzles 22 may be used at the time of region setting and at the time of coating.

When the curvature of the surface of the work W is large, the nozzle 22 is used less frequently. Therefore, it is preferable to apply a dummy coating to the nozzle 22 which is not used for a certain period of time for cleaning.

As a result, a pattern can be drawn with high accuracy on the work W having a curved surface. As described above, the printing apparatus 1 can be used for designing the appearance of the product, drawing the wiring pattern on the three-dimensional surface, and the like.

<< Embodiment 2 >>
FIG. 17 is a plan view showing a schematic configuration of the printing apparatus according to the second embodiment. Hereinafter, the same parts as those in the first embodiment are designated by the same reference numerals, and only the differences will be described.

As shown in FIG. 17, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a C'axis rotation mechanism 38.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

The Y-axis linear motion mechanism 31 is mounted on the gantry 2. The Y-axis linear motion mechanism 31 moves the work W in the sub-scanning direction.

The C-axis rotation mechanism 37 is attached to the Y-axis linear motion mechanism 31. The C-axis rotation mechanism 37 rotates the work W around the C-axis extending in the Z direction.

The Z-axis linear motion mechanism 32 is attached to the C-axis rotation mechanism 37. The Z-axis linear motion mechanism 32 moves the work W in the vertical direction.

The A-axis rotation mechanism 35 is attached to the Z-axis linear motion mechanism 32. The A-axis rotation mechanism 35 rotates the work W around the A-axis extending in the X direction.

The B-axis rotation mechanism 36 is attached to the A-axis rotation mechanism 35 via the holding body 42. The fixing jig 40 is attached to the B-axis rotation mechanism 36 via the support arm 41. The B-axis rotation mechanism 36 rotates the work W around the B-axis extending in the Y direction.

With such a configuration, it is possible to widen the adjustment range of the posture of the work W, speed up the posture adjustment according to the curved surface of the work W, and print on the work W with high accuracy.

<< Embodiment 3 >>
As shown in FIG. 18, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a C'axis rotation mechanism 38.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

The Y-axis linear motion mechanism 31 is mounted on the gantry 2. The Y-axis linear motion mechanism 31 moves the work W in the sub-scanning direction.

The Z-axis linear motion mechanism 32 is attached to the Y-axis linear motion mechanism 31. The Z-axis linear motion mechanism 32 moves the work W in the vertical direction.

The C-axis rotation mechanism 37 is attached to the Z-axis linear motion mechanism 32 via the first arm 61. The C-axis rotation mechanism 37 rotates the work W around the C-axis extending in the Z direction.

The A-axis rotation mechanism 35 is attached to the C-axis rotation mechanism 37 via the second arm 62. The A-axis rotation mechanism 35 rotates the work W around the A-axis extending in the X direction.

The B-axis rotation mechanism 36 is attached to the A-axis rotation mechanism 35 via the third arm 63. The fixing jig 40 is attached to the B-axis rotation mechanism 36. The B-axis rotation mechanism 36 rotates the work W around the B-axis extending in the Y direction.

With such a configuration, it is possible to widen the adjustment range of the posture of the work W, speed up the posture adjustment according to the curved surface of the work W, and print on the work W with high accuracy.

<< Embodiment 4 >>
As shown in FIG. 19, the printing unit 10 has a two-axis drive mechanism and a plurality of inkjet units 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a plurality of C'axis rotation mechanisms 38.

The plurality of inkjet units 20 are attached to the X-axis linear motion mechanism 11 via the plurality of C'axis rotation mechanisms 38, respectively. The C'axis rotation mechanism 38 rotates the head portion 21 of the inkjet unit 20 in the horizontal direction around the C'axis extending in the vertical direction.

The X-axis linear motion mechanism 11 is composed of a linear motor type drive mechanism, and drives a plurality of inkjet units 20 separately in the X direction. The X-axis linear motion mechanism 11 may be configured by a belt-type drive mechanism. As a result, only the inkjet unit 20 involved in printing can be opposed to the surface of the work W, and the inkjet unit 20 not involved in printing can be retracted from the work W.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

With such a configuration, by printing only the inkjet unit 20 containing the material to be printed close to the work W, it is possible to prevent the other inkjet units 20 from interfering with the work W. As a result, the degree of freedom of the posture adjustment operation of the work W can be increased.

<< Embodiment 5 >>
As shown in FIGS. 20 and 21, the printing unit 10 includes an X-axis linear motion mechanism 11 which is a uniaxial drive mechanism, and an inkjet unit 20. The inkjet unit 20 is attached to the X-axis linear motion mechanism 11.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

The Y-axis linear motion mechanism 31 is mounted on the gantry 2. The Y-axis linear motion mechanism 31 moves the work W in the sub-scanning direction.

The C-axis rotation mechanism 37 is attached to the Y-axis linear motion mechanism 31. The C-axis rotation mechanism 37 rotates the work W around the C-axis extending in the Z direction.

The Z-axis linear motion mechanism 32 is attached to the C-axis rotation mechanism 37. The Z-axis linear motion mechanism 32 moves the work W in the vertical direction.

The B-axis rotation mechanism 36 is attached to the Z-axis linear motion mechanism 32. The B-axis rotation mechanism 36 rotates the work W in the vertical direction around the B-axis extending in the X direction.

The A-axis rotation mechanism 35 is attached to the B-axis rotation mechanism 36 via the support arm 41. The A-axis rotation mechanism 35 rotates the work W around the A-axis extending in the Z direction.

With such a configuration, it is possible to widen the adjustment range of the posture of the work W, speed up the posture adjustment according to the curved surface of the work W, and print on the work W with high accuracy.

<< Embodiment 6 >>
FIG. 22 is a side view showing a schematic configuration of the printing apparatus according to the sixth embodiment. Hereinafter, the same parts as those in the fifth embodiment are designated by the same reference numerals, and only the differences will be described.

As shown in FIG. 22, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a C'axis rotation mechanism 38.

The C'axis rotation mechanism 38 is attached to the X-axis linear motion mechanism 11. The inkjet unit 20 is attached to the X-axis linear motion mechanism 11 via the C'axis rotation mechanism 38. The C'axis rotation mechanism 38 rotates the head portion 21 in the horizontal direction about the C'axis extending in the vertical direction.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

With such a configuration, the head portion 21 is moved in the main scanning direction by the X-axis linear motion mechanism 11, and the position of the nozzle 22 of the head portion 21 with respect to the work W is finely adjusted by the C'axis rotation mechanism 38. can do. As a result, the image can be printed on the work W by changing the print pitch.

<< Embodiment 7 >>
As shown in FIG. 23, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a Y'axis linear motion mechanism 13 (secondary scanning linear motion mechanism).

The Y'axis linear motion mechanism 13 is attached to the X-axis linear motion mechanism 11. The inkjet unit 20 is attached to the X-axis linear motion mechanism 11 via the Y'axis linear motion mechanism 13.

The inkjet unit 20 has a plurality of head units 21. The Y'axis linear motion mechanism 13 moves at least one of the plurality of head portions 21 in the sub-scanning direction. For example, of the plurality of head portions 21, only the head portion 21 including the material (color, material, etc.) to be printed is moved in the sub-scanning direction.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

With such a configuration, by printing only the head portion 21 containing the material to be printed close to the work W, it is possible to prevent the other head portions 21 from interfering with the work W. As a result, the degree of freedom of the posture adjustment operation of the work W can be increased.

<< Embodiment 8 >>
As shown in FIG. 24, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a Z'axis linear motion mechanism 14 (advance / retreat linear motion mechanism).

The Z'axis linear motion mechanism 14 is attached to the X-axis linear motion mechanism 11. The inkjet unit 20 is attached to the X-axis linear motion mechanism 11 via the Z'axis linear motion mechanism 14.

The inkjet unit 20 has a plurality of head units 21. The Z'axis linear motion mechanism 14 advances and retreats at least one of the plurality of head portions 21 with respect to the work W. For example, among the plurality of head portions 21, only the head portion 21 including the material (color, material, etc.) to be printed is moved downward.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

With such a configuration, by printing only the head portion 21 containing the material to be printed close to the work W, it is possible to prevent the other head portions 21 from interfering with the work W. As a result, the degree of freedom of the posture adjustment operation of the work W can be increased.

Further, even if the surface of the work W has a recess, the head portion 21 can be brought close to the recess to eject the droplet 25, and a pattern can be drawn with high accuracy on the work W.

<< Embodiment 9 >>
As shown in FIG. 25, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a Z'axis linear motion mechanism 14.

The work drive unit 30 has a 5-axis drive mechanism. Two of the five-axis drive mechanisms are a Y-axis linear motion mechanism 31 and a Z-axis linear motion mechanism 32. Of the five-axis drive mechanisms, three are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, and the C-axis rotation mechanism 37.

The Y-axis linear motion mechanism 31 is mounted on the gantry 2. The Y-axis linear motion mechanism 31 moves the work W in the sub-scanning direction.

The Z-axis linear motion mechanism 32 is attached to the Y-axis linear motion mechanism 31. The Z-axis linear motion mechanism 32 moves the work W in the vertical direction.

The C-axis rotation mechanism 37 is attached to the Z-axis linear motion mechanism 32. The C-axis rotation mechanism 37 rotates the work W in the vertical direction around the C-axis extending in the horizontal direction.

The B-axis rotation mechanism 36 is attached to the C-axis rotation mechanism 37 via the first arm 61. The B-axis rotation mechanism 36 rotates the work W around the B-axis extending along the longitudinal direction of the first arm 61.

The A-axis rotation mechanism 35 is attached to the B-axis rotation mechanism 36 via the second arm 62. The A-axis rotation mechanism 35 rotates the work W around the A-axis extending along the longitudinal direction of the second arm 62.

With such a configuration, the adjustment range of the posture of the work W can be further widened by increasing the number of drive mechanisms of the work drive unit 30.

The printing unit 10 may have an X-axis linear motion mechanism 11 and a Y'axis linear motion mechanism for moving the head portion 21 in the sub-scanning direction.

<< Embodiment 10 >>
As shown in FIG. 26, the printing unit 10 has a two-axis drive mechanism and an inkjet unit 20. The two-axis drive mechanism includes an X-axis linear motion mechanism 11 and a Z'axis linear motion mechanism 14.

The work drive unit 30 has a 7-axis drive mechanism. One of the seven-axis drive mechanisms is the Y-axis linear motion mechanism 31. Of the seven-axis drive mechanisms, six are the A-axis rotation mechanism 35, the B-axis rotation mechanism 36, the C-axis rotation mechanism 37, the D-axis rotation mechanism 66, the E-axis rotation mechanism 67, and the F-axis rotation mechanism 68.

The Y-axis linear motion mechanism 31 is mounted on the gantry 2. The Y-axis linear motion mechanism 31 moves the work W in the sub-scanning direction.

The F-axis rotation mechanism 68 is attached to the Y-axis linear motion mechanism 31. The F-axis rotation mechanism 68 rotates the work W in the horizontal direction around the F-axis extending in the vertical direction.

The E-axis rotation mechanism 67 is attached to the F-axis rotation mechanism 68 via the first arm 61. The E-axis rotation mechanism 67 rotates the work W around the E-axis extending in the X direction.

The D-axis rotation mechanism 66 is attached to the E-axis rotation mechanism 67 via the second arm 62. The D-axis rotation mechanism 66 rotates the work W around the D-axis extending in the X direction.

The C-axis rotation mechanism 37 is attached to the D-axis rotation mechanism 66 via the third arm 63. The C-axis rotation mechanism 37 rotates the work W around the C-axis extending along the longitudinal direction of the third arm 63.

The B-axis rotation mechanism 36 is attached to the C-axis rotation mechanism 37 via the fourth arm 64. The B-axis rotation mechanism 36 rotates the work W around the B-axis extending in the X direction.

The A-axis rotation mechanism 35 is attached to the B-axis rotation mechanism 36 via the fifth arm 65. The A-axis rotation mechanism 35 rotates the work W around the A-axis extending along the longitudinal direction of the fifth arm 65.

With such a configuration, it is possible to widen the adjustment range of the posture of the work W, speed up the posture adjustment according to the curved surface of the work W, and print on the work W with high accuracy.

The printing unit 10 may have an X-axis linear motion mechanism 11 and a Y'axis linear motion mechanism for moving the head portion 21 in the sub-scanning direction.

As described above, the present invention is extremely useful and has high industrial applicability because it has a highly practical effect of being able to print accurately on a workpiece having a three-dimensional curved surface. ..

1 Printing device 10 Printing unit 11 X-axis linear motion mechanism (main scanning linear motion mechanism)
12 Head rotation mechanism 13 Y'axis linear motion mechanism (secondary scanning linear motion mechanism)
14 Z'axis linear motion mechanism (advance / retreat linear motion mechanism)
21 Head part 25 Droplets 30 Work drive unit 31 Y-axis linear motion mechanism 32 Z-axis linear motion mechanism 35 A-axis rotation mechanism 36 B-axis rotation mechanism 37 C-axis rotation mechanism 38 C'axis rotation mechanism W work

Claims (7)

A printing device that prints a predetermined image by ejecting droplets onto a workpiece having a curved surface.
A printing unit having a head portion that ejects droplets on the surface of the work, and a printing unit.
A work drive unit that changes the posture of the work to adjust the distance between the surface of the work and the head portion is provided.
The work drive unit has a drive mechanism of at least 5 axes.
A printing device in which at least three of the five-axis drive mechanisms are rotary mechanisms. In claim 1,
The printing unit is a printing device having a drive mechanism of at least one axis. In claim 2,
The printing unit is a printing device having a main scanning linear motion mechanism for moving the head portion in the main scanning direction and a uniaxial rotation mechanism. In claim 2,
The printing unit includes a plurality of the head portions, a main scanning linear motion mechanism for moving the plurality of head portions in the main scanning direction, and a sub-order in which at least one of the plurality of head portions intersects the main scanning direction. A printing device equipped with a sub-scanning linear motion mechanism that moves in the scanning direction. In claim 2,
The printing unit includes a plurality of the head portions, a main scanning linear motion mechanism for moving the plurality of head portions in the main scanning direction, and advancing / retreating of at least one of the plurality of head portions with respect to the work. A printing device having a linear motion mechanism. In any one of claims 1 to 5,
The work drive unit is
A Y-axis linear motion mechanism that moves the work in the Y direction orthogonal to the X direction, which is the main scanning direction,
A Z-axis linear motion mechanism provided in the Y-axis linear motion mechanism and moving the work in the Z direction orthogonal to the X direction and the Y direction.
An A-axis rotation mechanism provided in the Z-axis linear motion mechanism and rotating the work around the A-axis extending in the X direction.
A B-axis rotation mechanism provided in the A-axis rotation mechanism and rotating the work around the B-axis extending in the Y direction, and a B-axis rotation mechanism.
A printing device provided in the B-axis rotation mechanism and having a C-axis rotation mechanism for rotating the work around the C-axis extending in the Z direction. In any one of claims 1 to 5,
The work drive unit is
A Y-axis linear motion mechanism that moves the work in the Y direction orthogonal to the X direction, which is the main scanning direction,
A C-axis rotation mechanism provided in the Y-axis linear motion mechanism and rotating the work around the C-axis extending in the X-direction and the Z-direction orthogonal to the Y-direction.
A Z-axis linear motion mechanism provided in the C-axis rotation mechanism to move the work in the Z direction, and a Z-axis linear motion mechanism.
An A-axis rotation mechanism provided in the Z-axis linear motion mechanism and rotating the work around the A-axis extending in the X direction.
A printing device provided in the A-axis rotation mechanism and having a B-axis rotation mechanism for rotating the work around the B-axis extending in the Y direction.

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