JP3295262B2 - Ink jet printing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink-jet printing method and an ink-jet printing apparatus capable of always maintaining a proper distance between a printing surface and an ink-jet head for various printing objects having different thicknesses.

[0002]

2. Description of the Related Art In an ink jet system, ink droplets are ejected from an ink ejection port formed in an ink jet head toward a printing surface of a printing object, and desired information is printed on the printing surface of the printing object. I have. For this reason, it is important to maintain a constant distance between the ink discharge port of the inkjet head and the print surface of the print target in order to ensure print quality.

Conventionally, a sheet of paper having a thickness of about 0.15 to 0.2 mm has been considered exclusively as a printing target. Therefore, the distance between the ink discharge port of the ink jet head and the printing surface of the printing target has to be increased. It was possible to print on paper of a general thickness with almost no problem simply by mechanically setting in advance.

[0004] In addition, a printing apparatus having a mechanism for adjusting the distance between the ink jet head and the printing object according to the type of the printing object has been put into practical use. At most only corresponds to the thickness of paper, such as cardboard, which is generally recognized as paper. In other words, there is no known inkjet printing apparatus that can appropriately adjust the distance between the inkjet head and the printing surface of the printing target for various printing targets such as wood, resin, and metal.

[0005]

In recent years, by utilizing the features of the ink jet system, in addition to wood, resin or metal plates, desired image information is printed on cloth or the like, or metal plates for printing plates are used. It is considered that an operation of applying an etchant to the substrate is performed by an inkjet method.

In consideration of performing ink-jet printing on such various print objects, it is necessary to assemble a mechanism capable of adjusting a distance between an ink discharge port of an ink-jet head and a print surface of the print object. is there. From such a viewpoint, Japanese Patent Laid-Open No.
As is well known in Japanese Patent Application Publication No. 520, an ink jet printing apparatus incorporating a mechanism for adjusting a distance between an ink discharge port of an ink jet head and a printing surface of a print target has been proposed.

However, in the ink jet printing apparatus disclosed in Japanese Patent Application Laid-Open No. 1-219520, since the gap adjustment sensor is always in contact with the printing surface of the printing object, the printing surface has a streak. There is a risk that the surface may be scratched or the printed surface may be stained in some cases.

Further, in this conventional ink jet printing apparatus, only a printing object having a constant thickness can be printed. For example, a printing object whose thickness changes in a wedge-like manner is treated in some way. No printing could be done on the printing surface without using a tool.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet printing method and an ink jet printing apparatus capable of maintaining a predetermined distance between an ink jet head of an ink jet unit and a print surface of a print object with respect to a print surface of a print object having a different thickness. Is to provide.

[0010]

According to a first aspect of the present invention, there is provided a printing object mounting portion on which a printing object is mounted, and a mounting portion of an inkjet unit to which an inkjet head facing the printing object is mounted. Transport means for transporting the print object placement section, and the print object placement section can be inclined along a width direction orthogonal to a transport direction of the print object placement section by the transport means. Moving means for relatively moving the mounting portion of the ink jet unit and the printing object mounting portion in the facing direction thereof, and a plurality of moving means provided along the width direction on the mounting portion side of the ink jet unit, Using an inkjet printing apparatus having a gap adjustment sensor capable of abutting the print surface of each An inkjet printing method for printing predetermined information on the print surface of the print target, wherein the moving unit is driven in a direction in which the gap adjustment sensor can contact the print surface of the print target, and the print target is printed. A first moving step of bringing the gap adjustment sensor into contact with the print surface of the object, and driving the moving means in reverse when the gap adjustment sensor is brought into contact with the print surface of the print target, A second moving step of relatively moving the mounting portion of the ink jet unit and the printing object mounting portion relative to each other by a predetermined amount in a direction in which the gap adjustment sensor moves away from the printing surface of the printing object; With the gap adjustment sensor separated from the print surface by a predetermined amount,
Printing the predetermined information on the print surface of the print target by relatively moving the print target mounting portion and the mounting portion of the inkjet unit in a direction parallel to the print surface of the print target. The second moving step is based on a result of the plurality of gap adjustment sensors contacting the printing surface of the printing object with the printing surface in the first moving step. The printing object placement part is moved so as to incline along. According to a second aspect of the present invention, there is provided a print target mounting portion on which a print target is mounted, a mounting portion of an inkjet unit to which an inkjet head facing the print target is mounted, and the print target mounting portion. Conveying means for conveying, moving means for relatively moving the mounting portion of the ink jet unit and the print object mounting portion in the facing direction thereof, and the printing object by the conveying means on the mounting portion side of the ink jet unit Printing of the print target using an inkjet printing apparatus having a gap adjustment sensor that is provided movably along a width direction orthogonal to the transport direction of the mounting unit and that can contact the print surface of the print target. This is an inkjet printing method for printing predetermined information on the surface. Driving the moving means in a direction in which the gap adjustment sensor can abut on the printing surface of the printing object, and bringing the gap adjustment sensor into contact with the printing surface of the printing object; When the gap adjustment sensor is brought into contact with the print surface of the object, the moving unit is driven in reverse, and the mounting unit of the inkjet unit is moved in a direction in which the gap adjustment sensor is separated from the print surface of the print target. Relative moving the print target mounting portion by a predetermined amount; and attaching the print target mount portion and the ink jet unit in a state where the gap adjustment sensor is separated from the print surface of the print target by a predetermined amount. Relative to the printing object in a direction parallel to the printing surface of the printing object. It is characterized in that comprising the step of printing predetermined information on the printing surface.

Here, it is effective that the moving means is capable of relatively moving the printing object placing portion in a direction opposite to a mounting portion of the ink jet unit.

The gap adjusting sensor includes a lever having one end protruding toward the printing surface of the printing object, and a biasing means for urging one end of the lever toward the printing surface of the printing object. And a switch for detecting a displacement equal to or greater than a predetermined value at the other end of the lever against the urging means.

Further, the method further comprises the step of driving the moving means to set a predetermined interval between the mounting portion of the ink jet unit and the mounting portion of the print object, whereby the mounting portion of the ink jet unit and the printing portion are set. The moving unit may be driven in a direction in which the gap adjustment sensor can come into contact with the print surface of the print target from a state in which the target mount is set at the predetermined interval.

On the other hand, a third embodiment according to the present invention is directed to a printing object mounting portion on which a printing object is mounted, and a printing object mounting portion provided so as to be relatively movable in a direction facing the printing object mounting portion. Attachment section of an inkjet unit to which an inkjet head capable of facing a print surface of an object is attached, transport means for transporting the print object placement section, and a transport direction of the print object placement section by the transport means. Moving means for relatively moving the mounting portion of the ink jet unit and the printing object mounting portion in a direction opposite to each other such that the printing object mounting portion can be inclined along the orthogonal width direction; A plurality of units are provided movably along the width direction on the mounting portion side of the unit, and are provided in front of the print target. A gap adjustment sensor capable of abutting the print surface, and driving the moving unit in a direction in which the gap adjustment sensor can abut the print surface of the print target, and adjusting the gap to the print surface of the print target. When the sensor contacts, the moving unit is driven in reverse, and the mounting unit of the ink jet unit and the printing object placement unit are positioned in a direction in which the gap adjustment sensor is separated from the printing surface of the printing object. Control means for performing a fixed relative movement; and scanning means for relatively moving the printing object mounting portion and the ink jet unit mounting portion in a direction parallel to the printing surface of the printing object. In an inkjet printing device. According to a fourth aspect of the present invention, there is provided a printing object mounting portion on which a printing object is mounted, and a printing surface of the printing object provided so as to be relatively movable in a direction facing the printing object mounting portion. A mounting unit of an ink jet unit to which an ink jet head capable of facing the print head is mounted, a conveying unit for conveying the print target mounting portion, and a mounting portion of the ink jet unit and the print target mounting portion in the facing direction. A moving means for relatively moving the printing object, the moving means being provided on the mounting portion side of the ink jet unit along a width direction orthogonal to a conveying direction of the printing object mounting portion by the conveying means, and A gap adjustment sensor capable of abutting a printing surface, and the gap adjustment on the printing surface of the printing object. The moving means is driven in a direction in which the sensor can abut, and when the gap adjustment sensor abuts on the printing surface of the printing object, the moving means is driven in reverse, so that the printing surface of the printing object. Control means for relatively moving the mounting portion of the ink jet unit and the printing object mounting portion in a direction away from the gap adjustment sensor by a predetermined amount,
An ink jet printing apparatus comprising: a scanning unit that relatively moves the printing object placement unit and the mounting unit of the inkjet unit in a direction parallel to the printing surface of the printing object.

Here, it is effective that the moving means is capable of relatively moving the printing object placing portion in a direction facing the mounting portion of the ink jet unit.

The gap adjusting sensor includes a lever having one end protruding toward the printing surface of the printing object, and an urging means for urging one end of the lever toward the printing surface of the printing object. And a switch for detecting a displacement equal to or greater than a predetermined value at the other end of the lever against the biasing means.

Further, the apparatus further includes initial setting means for setting a predetermined interval between the mounting portion of the ink jet unit and the print object placing portion, and the control means controls the mounting of the ink jet unit by the initial setting means. The moving means may be driven in a direction in which the gap adjustment sensor can come into contact with the print surface of the print object from a state in which the unit and the print object mounting portion are set at a predetermined interval. . In this case, it is preferable that the initial setting unit is an origin position detection sensor for holding a mechanical position of the moving unit at a predetermined position.

It is effective that the ink-jet head generates bubbles in the ink using thermal energy and discharges the ink based on the bubbles.

[0019]

According to the present invention, the control means drives the moving means in a direction in which the gap adjustment sensor can come into contact with the print surface of the print object to relatively move the mounting portion of the ink jet unit and the print object placing portion. . When the gap adjustment sensor comes into contact with the print surface of the print target, the moving unit is driven in reverse, and the mounting portion of the ink jet unit and the print target are placed in a direction in which the gap adjustment sensor is separated from the print surface of the print target. Relative to the mounting portion by a predetermined amount.

Thus, the ink jet unit and the printing surface of the printing object are set at a predetermined distance, and the gap adjustment sensor is kept in a non-contact state with the printing surface of the printing object. The printing object mounting portion and the mounting portion of the inkjet unit are relatively moved in a direction parallel to the printing surface of the printing object, and predetermined information is printed on the printing surface of the printing object.

Here, in the case of a printing object in which the surface in contact with the printing object mounting portion and the printing surface are parallel, the moving means moves the printing object mounting portion relative to the direction in which the mounting portion of the ink jet unit faces. By adopting an object that can be translated in parallel, the relative movement surface between the printing surface of the printing object and the mounting portion of the inkjet unit during printing becomes parallel. In addition, in the case of a printing object in which the surface contacting the printing object mounting portion and the printing surface are inclined along the width direction of the printing object mounting portion, the printing object mounting portion is moved in the width direction. By inclining along the plane, the printing surface of the printing object and the relative movement surface of the mounting portion of the inkjet unit during printing become parallel.

A lever having one end protruding toward the printing surface of the printing object, a biasing means for biasing one end of the lever toward the printing surface of the printing object, and a biasing means against the biasing means When using a gap adjustment sensor having a switch for detecting a displacement equal to or greater than a predetermined value at the other end of the lever,
By driving the moving means in a direction in which the gap adjustment sensor can contact the printing surface of the printing object, the printing surface of the printing object presses against one end of the lever against the urging means, and the other side of the lever is pressed. The end side starts to be displaced, and when this is displaced by a predetermined amount or more, the switch is switched, and the signal is output to the control means.

When the print surface of the print object is protruded from other portions and exists only in a part of the print object mounting portion along the width direction, the gap adjustment sensor is used to detect the print object on which the print surface exists. It moves in the width direction of the object placing part. When the print surface of the print target is inclined along the width direction of the print target mounting portion, the two gap adjustment sensors are positioned on both sides in the width direction of the print target, and the print target mount is placed. By tilting the part,
Both sides in the width direction of the printing object are brought into contact with the gap adjustment sensors.

On the other hand, when the apparatus further comprises initial setting means for setting a predetermined interval between the mounting section of the ink jet unit and the print object placing section, the control means controls the mounting section of the ink jet unit by the initial setting means. The moving unit is driven in a direction in which the gap adjustment sensor can come into contact with the print surface of the print target from a state in which the space between the print target mount and the print target mounting portion is set at a predetermined interval. When an origin position detecting sensor is employed as the initial setting means, the mechanical position of the moving means is held at a predetermined position based on the output from the origin position detecting sensor, whereby the mounting portion of the ink jet unit and the printing object are A predetermined interval is set with respect to the mounting portion.

When an ink jet head that uses heat energy to generate air bubbles in ink and discharges ink based on the air bubbles is adopted, at least a rapid temperature rise exceeding nucleate boiling corresponding to print information is provided. By applying one drive signal to the electrothermal transducer, heat energy is generated in the electrothermal transducer, causing film boiling on the heat-acting surface of the ink-jet head. A bubble of the formed ink is formed. The ink is ejected from the ink ejection port of the inkjet head by the growth and contraction of the bubble, and at least one ink droplet is formed on the print surface of the printing target.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the ink jet printing apparatus according to the present invention will be described in detail with reference to FIGS.

As shown in FIG. 1 showing a schematic structure of an embodiment in which desired printing is performed on a rectangular plate having a printing surface parallel to the back surface thereof, and FIG. The base plate 13 having a plurality of pedestals 12 mounted on a mounting surface 11 such as a floor or a table is vertically vertically (upward in FIG. 1) on both front and rear ends (left and right ends in FIG. 1). A pair of elevating guide rods 14 are provided to extend.

A cam shaft bracket 16 for rotatably supporting a pair of front and rear cam shafts 15I and 150 is provided on the left and right sides of the base plate 13 intersecting the arrangement direction of the elevating guide bars 14, respectively. And fixed on the back side. These camshaft brackets 16 are parallel to each other and parallel to the surface of the base plate 13.
A pair of front and rear cam shafts 15I, 15 rotatably supported by
The eccentric cams 17 are integrally formed with O, respectively. An endless toothed belt 19 is provided on the synchronous gears 18 provided on one end sides of the pair of front and rear cam shafts 15I and 150 so that the rotational phases of the eccentric cams 17 with respect to the cam shafts 15I and 150 are always matched. Wrapped around
The height from the surface of the base plate 13 to the upper end surface of each eccentric cam 17 is always set to be equal.

It should be noted that between one camshaft 15I and a camshaft bracket 16 supporting this one camshaft 15I,
In order to adjust the tension of the toothed belt 19, a tension adjusting mechanism (not shown) that can move the other cam shaft 15 </ b> I relative to the cam shaft bracket 16 in the front-rear direction of the base plate 13 is incorporated.

A camshaft driven gear 2 is provided at one end of one camshaft 150 which is rotatably supported in a penetrating state by one camshaft bracket 16 provided at one end of the base plate 13.
0 and a rotating disk 21 for detecting the later-described origin positions of the camshafts 15I and 15O are provided coaxially and integrally.
The camshaft bracket 16 has camshafts 15I,
A forward / reverse rotatable stepping motor (hereinafter, referred to as a camshaft drive motor) 22 for driving the motor 150 is mounted, and the rotational force of a camshaft drive gear 23 integrated with the camshaft drive motor 22 is controlled by the motor. Camshaft driven gear 2
A reduction gear group 24 for transmitting to zero is provided rotatably. One notch (not shown) is formed in the outer peripheral edge of the rotating disk 21, and an origin position detecting sensor 25 for detecting the notch is attached to the base plate 13. When the origin position detecting sensor 25 detects the notch of the rotating disk 21, the distance from the cam shafts 15I, 150 to the upper end surface of the eccentric cam 17 is set to be minimum as shown in FIG. ing.

That is, the origin position of the cam shafts 15I and 150 is the rotational phase of the cam shafts 15I and 150 where the distance from the cam shafts 15I and 150 to the upper end surface of the eccentric cam 17 is minimum. The cam shaft drive gear 23 of the shaft drive motor 22 rotates forward, and the elevating table 2
6 is raised with respect to the base plate 13. The camshaft drive motor 22, the reduction gear group 24, the camshaft driven gear 20, the camshafts 151, 150, the eccentric cam 17, and the like constitute the moving means of the present invention.

On the other hand, the front and rear ends of a lifting table 26 mounted on the eccentric cams 17 are slidably fitted to the lifting guide rods 14 such that the back surface is in sliding contact with the eccentric cams 17. The ascending and descending guide cylinders 27 project downward, respectively. Further, between the elevating table 26 and the base plate 13, the elevating table 26 is always provided with the eccentric cam 17.
A tension spring 28 for urging the elevating table 26 toward the base plate 13 is interposed so as to abut the cam shaft drive motor 22.
As the I and 150 rotate synchronously, the lifting table 2
6 along the elevating guide rod 14 on the base plate 13 in FIG.
It is designed to go up and down inside and down.

At the front and rear ends of the lifting table 26, a pair of front and rear pulley shafts 29I and parallel to the cam shafts 15I and 150 are provided.
Pulley shaft brackets 30 that rotatably support 29O are fixed to the left and right sides of the elevating table 26, respectively. An endless transport belt 32 is wound around a belt pulley 31 integrally formed on each of the pulley shafts 29I and 29O, and a print target 33 is placed on a predetermined position of the transport belt 32. Has become. That is, the transport belt 32 corresponds to the print target placing portion of the present invention.

A pulley shaft bracket 30 for supporting one end of one pulley shaft 29I has a pulley shaft 29I, 2
A stepping motor (hereinafter, referred to as a pulley shaft drive motor) 34 for driving 9O is attached, and the rotational force of a pulley shaft drive gear 35 integrated with the pulley shaft drive motor 34 is applied to one pulley shaft 29I. A reduction gear 37 for transmitting to a pulley shaft driven gear 36 provided on one end side of the motor is rotatably provided.

Accordingly, when the pulley shaft drive motor 34 is operated, one of the pulley shafts 29I is driven, and accordingly, the conveyor belt 32 turns counterclockwise in FIG. The print object 33 placed on the right side in the figure is moved to one end side of the elevating table 26 (the left side in the figure).
To be transported.

The tension between the pulley shaft 29O and the pulley shaft bracket 30 supporting the other pulley shaft 29O is adjusted so that the tension of the conveyor belt 32 can be adjusted.
A tension adjusting mechanism (not shown) that can relatively move the other pulley shaft 29O relative to the pulley shaft bracket 30 in the front-rear direction of the base plate 13 is incorporated.

At the left and right ends of a top beam 38 which straddles the center of the elevating table 26 in the left-right direction, the upper end of a column 40 whose lower end is detachably screwed to the base plate 13 via a height adjustment block 39 is provided. Each is integrally connected. In the present embodiment, the cam shafts 15I and 150 are driven and rotated to adjust the amount of eccentricity of the eccentric cam 17 in order to maintain a constant distance between the printing surface 41 of the printing object 33 and an inkjet head 42 described later. However, when printing is performed on a print object 33 having a significantly different thickness that cannot be dealt with only by the amount of eccentricity of the cam shafts 15I and 150, the height adjustment block 39 having an appropriate thickness is replaced. I can do it. For this reason, a positioning pin 43 is interposed between the base plate 13 and the column 40 so that the relative position of the column 40 with respect to the base plate 13 can always be accurately positioned.

At the upper ends of the pair of left and right columns 40, both ends of a unit guide rod 44 and a main scanning screw shaft 45 parallel to the cam shafts 15I and 150 are attached. Is rotatably supported by the column 40. One end of the main scanning screw shaft 45 is connected to a forward / reverse rotatable stepping motor (hereinafter referred to as a main scanning screw shaft driving motor) 46 attached to the upper end of one column 40. The ink jet unit 47 screwed with the main scanning screw shaft 45 and through which the unit guide rod 44 slidably penetrates is provided by the main scanning screw shaft driving motor 46.
With the operation of the main scanning screw shaft 45, the main scanning screw shaft 45 can reciprocate right and left along the unit guide rod 44 above the transport belt 32. That is, top beam 3
The column 8, the column 40, the unit guide bar 44, the main scanning screw shaft 45, and the like correspond to the inkjet unit mounting portion of the present invention.

The ink jet unit 47 in this embodiment is equipped with an ink jet head 42 in which a plurality of ink discharge ports (not shown) opened downward at the lower end thereof are arranged in front and rear (in the horizontal direction in the figure). ,
For example, those known in JP-A-6-199006 and the like are employed. In this case, an ink tank (not shown) that supplies ink to the inkjet head 42 can be exchangeably mounted on the inkjet unit 47, or can be exchangeably mounted on the top beam 38 or the column 40. When the ink tank is mounted on the ink jet unit 47, the ink tank may be formed so as to be separable from the ink jet head 42, or may be formed integrally with the ink jet head 42.

As shown in FIG. 2 and FIG. 3 in which the upper end of the column 40 is extracted and enlarged, a cam shaft is provided on a guide rod support arm 48 projecting from the upper end of the column 40 to the other end of the elevating table 26, respectively. Both ends of a sensor holder guide bar 49 parallel to 151I and 150 are connected to the sensor holder guide bar 49, and a medium leading end detection sensor 50 for detecting the carry-in of the print object 33 and the ink jet head 42 and the print object. A sensor holder 52 having front and rear clearance adjustment sensors 51 for appropriately adjusting the gap with the object 33 is slidably penetrated. At the upper end of the sensor holder 52, the tip is a sensor holder guide rod 4
9 is screwed into the sensor holder 52, whereby the relative position of the sensor holder 52 along the longitudinal direction with respect to the sensor holder guide rod 49 can be arbitrarily fixed. It has become. Directly under the sensor holder guide rod 49, a detent rod 55 slidably engaged with a detent groove 54 formed at the lower end of the sensor holder 52 is disposed in parallel with the sensor holder guide rod 49. Both ends of the rotation preventing rod 55 are also integrally connected to the guide rod support arm 48, respectively.

In this embodiment, since the position of the sensor holder 52 can be moved along the sensor holder guide rod 49, as shown in FIGS. In addition, the print surface 41 to be printed on the print target 33 protrudes from other portions, and the print surface 41 to be printed exists only in a part of the print target 33 along the width direction. In such a case, the sensor holder 52 is
By moving to a position immediately above 1, even the print target 33 as shown in FIGS. 4 and 5 can be printed on the print surface 41 without any problem.

In the present embodiment, the medium leading edge detection sensor 50
Uses a reflection type photoelectric switch, and detects the position of the leading end of the print target 33 carried into the inkjet unit 47 side in a non-contact state. Further, the gap adjusting sensor 51 in the present embodiment includes a swing lever 56 having a bell crank shape, and a pivot pin 57 for pivotally pivoting the center of the swing lever 56 to the sensor holder 52.
A pull is provided between the upper end portion of the swing lever 56 and the sensor holder 52 so that the lower end portion of the swing lever 56 faces downward, that is, urges counterclockwise around the pivot pin 57 in FIG. It includes a spring 58 and a sensor switch 59 such as a transmission type photoelectric switch. Then, the tension spring 58
When the upper end of the swing lever 56 rotates clockwise or more by a predetermined amount against the spring force of the above, and the upper end of the swing lever 56 overlapping the sensor switch 59 is separated from the sensor switch 59 by a predetermined amount, The signal output from the gap adjusting sensor 51 is set to be ON.

As described above, the printing object 33 is mechanically
Since the lower end of the swing lever 56 is brought into contact with the print surface 41, the distance between the print surface 41 of the print target 33 and the inkjet head 42 can always be set accurately. Further, in this embodiment, when the gap adjustment sensor 51 is turned on, the normal rotation of the camshaft drive motor 22 is stopped, and when the camshaft drive motor 22 is further rotated in the reverse direction by a predetermined amount, the printing object 33 is rotated.
The distance G (see FIG. 3) between the print surface 41 and the ink jet head 42 is set to be an appropriate distance, whereby the gap adjustment sensor 51 temporarily moves with respect to the print surface 41 of the print target 33. I try to stop just contact.

In order to realize the above-described operation, as shown in FIG. 6 showing a control block of the present embodiment, the ink jet unit 47 is provided with an operation of the pulley shaft driving motor 34 and the main scanning screw shaft driving motor 46 and the like. And a print control circuit 60 for controlling the control. A power supply unit 62 containing a power supply circuit 61 for supplying stable electric power to each of the motors 22, 34, 46 is provided on the back side of the base plate 13. Gap adjusting circuit 63 for driving the motor 22
And an interface board 65 for transmitting print information input to the personal computer 64 and the like to the print control circuit 60 of the ink jet unit 47. The detection signals from the sensors 25 and 51 are sent to the gap adjusting circuit 6 via the sensor detecting circuit 66.
3 is output.

A plurality of types of printing switches 67 and a gap adjustment start switch 68 operated by an operator are mounted on the upper surface of the top beam 38. The print switch 67 is connected to the print control circuit 60 together with the above-described medium leading edge detection sensor 50, and the gap adjustment start switch 68 is connected to the gap adjustment circuit 63.

As shown in FIG. 7 showing the operation procedure of this embodiment, when the operator presses the clearance adjustment start switch 68 in step S1, it is determined in step S2 whether the origin position detection sensor 25 is on. judge. Here, if it is determined that the origin position detection sensor 25 is not turned on, the process proceeds to S3
Then, the camshaft drive motor 22 is rotated in the reverse direction, and it is determined again in step S4 whether the home position detection sensor 25 is ON. Then, the origin position detection sensor 2
If it is determined that 5 is not on, the process returns to step S3 to continue the reverse operation of the camshaft drive motor 22.

As described above, when it is determined in step S4 that the origin position detection sensor 25 has been turned on,
The reverse rotation operation of the camshaft drive motor 22 is stopped in step S5, and the normal rotation operation of the camshaft drive motor 22 is started in step S6. If it is determined in step S2 that the origin position detection sensor 25 is ON, the process directly proceeds to step S6 to start the normal rotation operation of the camshaft drive motor 22. Then, in step S7, it is determined whether or not the gap adjustment sensor 51 is ON.
If it is determined that this is not turned on, the process returns to step S6, and the normal rotation operation of the camshaft drive motor 22 is continued.

As described above, when it is determined in step S7 that the gap adjustment sensor 51 has been turned on, the process proceeds to step S7.
In step S8, the normal rotation of the camshaft drive motor 22 is stopped, and in step S9, the camshaft drive motor 22 is rotated in the reverse direction by a predetermined amount. 22 is stopped, and the ink jet head 42 and the print surface 4 of the print object 33 are stopped.
Adjustment of the gap with 1 is completed.

Thereafter, the operator presses the print switch 67 to activate the pulley shaft drive motor 34, and when the leading edge of the print object 33 is confirmed by the medium leading edge detection sensor 50, the print control circuit 60 turns the pulley shaft drive motor. By controlling the operation of the main scanning screw shaft drive motor 34 and the main scanning screw 46, predetermined image information is printed at a predetermined position on the print surface 41 of the print target 33, and the printed print target 33 is moved to one end of the lifting table 26. To be carried out.

When the thickness of the print object 33 gradually increases along the scanning direction of the transport belt 32 by the pulley shaft drive motor 34, the gap adjustment sensor 51 may be turned on during the printing operation. is there. In such a case, since there is a possibility that good quality printing may not be possible, in this embodiment, the gap adjusting sensor 5 is used during the printing operation.
When 1 is turned on, the operation of the pulley shaft drive motor 34 is stopped to prevent the gap adjustment sensor 51 from being damaged, and the printing operation is interrupted.

In the above-described embodiment, the present invention can be applied to the case where the back surface of the print object 33 abutting on the transport belt 32 and the print surface 41 are parallel, but the width direction orthogonal to the transport direction of the transport belt 32 is applicable. The present invention can also be applied to a print object 33 whose thickness gradually changes along the line.

FIG. 8 shows a plan structure of another embodiment of the present invention, and FIG. 9 shows a cross-sectional structure taken along the line IX-IX of FIG. 9. Members having basically the same functions as those of the previous embodiment are shown in FIG. Are denoted by the same reference numerals, and description thereof is omitted.
That is, at the front and rear ends of the back surface of the lifting table 26,
Fork-shaped connecting portions 70 formed on the upper end of the elevating guide rod 14 are swingably pivoted via connecting pins 69 extending in a direction parallel to the transport direction (left-right direction in the figure) of the printing object (not shown). The front and rear connecting pins 69 are arranged in a straight line. In addition, lift guide cylinders 27a, 27 which hold these lift guide rods 14 slidably.
b are attached to the front and back surfaces of both front and rear ends of the base plate 13, and in this embodiment, the elevating guide rods 14 are attached to the base plate 1.
3 can be penetrated. These lifting guide tubes 2
Cam shafts for rotatably supporting a pair of left and right cam shafts 15L and 15R opposed to each other on both left and right sides of the base plate 13 intersecting the front and rear arrangement direction of the base plate 7 with the front and rear elevating guide cylinders 27 interposed therebetween. Brackets 16 are fixed to the front and rear sides of the base plate 13, respectively. Eccentric cams 17L and 17R are integrally formed on a pair of left and right cam shafts 15L and 15R rotatably supported by the cam shaft brackets 16 so as to be parallel to each other and parallel to the surface of the base plate 13. Have been.

The camshaft driven gear 2 is provided at one end of the camshafts 15L and 15R rotatably supported by the left and right camshaft brackets 16 located at one end of the base plate 13 in a penetrating state.
0 and a rotating disk 21 for respectively detecting the origin positions of the cam shafts 15L and 15R, which will be described later, are provided coaxially and integrally. The camshaft brackets 16 are provided with camshaft drive motors 22L and 22R that can rotate forward and reverse for independently driving the camshafts 15L and 15R, respectively.
A reduction gear group 24 for transmitting the rotational force of the camshaft driving gear 23 integral with the 2R to the camshaft driven gear 20 is rotatably provided. Notches (not shown) are formed on the outer peripheral edge of the rotating disk 21 one by one, and origin position detection sensors 25L and 25R for detecting these notches are attached to the base plate 13, respectively. Then, these origin position detection sensors 25
When L, 25R detects a notch in the rotating disk 21, the distance from the cam shafts 15L, 15R to the upper end surfaces of the eccentric cams 17L, 17R is set to be minimum.

That is, the origin position of the cam shafts 15L, 15R is determined by moving the eccentric cams 17L, 1R from the cam shafts 15L, 15R.
Camshaft 15L, 1 that minimizes the distance to the upper end surface of 7R
The rotation phase is 5R. From this state, the camshaft drive gears 23 of the camshaft drive motors 22L and 22R rotate forward, respectively, and raise the elevating table 26 with respect to the base plate 13.

The sensor holder guide rod 49 having both ends connected to the support arm 48 of the column 40 has a medium leading end detection sensor 50 for detecting the carry-in of the print object and the left side of the lifting table 26 (the lower side in FIG. 8). 8), and a sensor holder 52 on which front and rear gap adjustment sensors 51L for appropriately adjusting the distance between the print target and the inkjet head 42 are attached, and the right side of the lifting table 26 (FIG. 8).
The sub sensor holder 71 to which the gap adjusting sensor 51R for appropriately adjusting the interval between the print object positioned at the middle and upper sides) and the inkjet head 42 is slidably penetrated. These sensor holders 52
A set screw 53 whose tip abuts on the sensor holder guide rod 49 is screwed into the upper end of the sub-sensor holder 71 and the sensor holder 5.
2, the relative position of the sensor holder 52 along the longitudinal direction with respect to the sensor holder guide rod 49 can be arbitrarily fixed. The position of the sensor holder 71 is moved according to the width of the print target.

In this embodiment, the gap adjusting sensor 51L,
When the camshaft drive motors 22L and 22R stop rotating forward when the respective 51Rs are turned on, and when the camshaft drive motors 22L and 22R are further reversed by a predetermined amount, respectively, the print surface of the print target and the ink jet head are stopped. 42 is set to be an appropriate distance. In other words, when the thickness of the print target in the width direction crossing the transport direction of the print target changes in a wedge shape, the position of the gap adjusting sensors 51L and 51R that is located on the thicker side first. Is turned on and the one located on the thinner side is then turned on, and the connecting pin 6
Lifting table 2 located on the thinner side with respect to 9
The sixth side is raised higher to be in an inclined state, and the printing surface of the printing object 33 is held parallel to the unit guide rod 44 and the main scanning screw shaft 45.

In the above two embodiments, the base plate 13
The gap between the print target 33 and the inkjet head 42 is adjusted by raising and lowering the elevating table 26 on which the print target 33 is placed, while fixing the height of the ink jet unit 47 from the base plate 13. Is fixed to the upper end surface of the conveyor belt 32, and the ink jet unit 47 is attached to the base plate 13.
, The gap between the print target 33 and the inkjet head 42 can be adjusted.

FIG. 10 shows a plan structure of another embodiment of the present invention. Members having basically the same functions as those of the previous embodiment are denoted by the same reference numerals, and description thereof is omitted. Shall be. That is, a pair of front and rear pulley shafts 29 are provided at both front and rear ends (left and right ends in the figure) of the base plate 13.
Pulley shaft brackets 30 that rotatably support I and 29O are fixed to both left and right sides of the base plate 13, respectively. An endless transport belt 32 is wound around a belt pulley 31 integrally formed on each of the pulley shafts 29I and 29O, and a print target 33 is placed on a predetermined position of the transport belt 32. Has become. A pulley shaft drive motor 34 for driving these pulley shafts 29I and 29O is attached to a pulley shaft bracket 30 that supports one end of one pulley shaft 29I. A reduction gear 37 for transmitting the rotational force of the gear 35 to a pulley shaft driven gear 36 provided at one end of one pulley shaft 29I is rotatably provided.

On the lower surface of the lower end of the column 40 extending downward from the left and right ends of the top beam 38 straddling the transport belt 32,
An elevating guide cylinder 27 slidably fitted to a pair of elevating guide rods 14 protruding vertically upward from the left and right ends of the base plate 13 is projected downward, whereby the column 40 and the top beam 38 are joined together. It can move up and down with respect to the base plate 13.

A pair of left and right camshafts 15 orthogonal to the pulley shafts 29I and 29O are provided on the left and right sides of the base plate 13, respectively.
A cam shaft bracket 16 that rotatably supports L and 15R is fixed to the front side and the rear side of the base plate 13, respectively. An eccentric cam 17 is integrally formed on the pair of left and right cam shafts 15L and 15R rotatably supported by the cam shaft brackets 16 so as to be parallel to each other and parallel to the surface of the base plate 13. I have.
The synchronous gears 1 provided on one end of the pair of left and right camshafts 15L, 15R so that the rotational phases of the eccentric cams 17 always coincide with the camshafts 15L, 15R.
An endless toothed belt 19 is wound around 8, and the height from the surface of the base plate 13 to the upper end surface of each eccentric cam 17 is always set to be equal.

A camshaft driven gear 2 is provided at one end of one camshaft 15L rotatably supported in a penetrating state by one camshaft bracket 16 provided at one end of the base plate 13.
0 and a rotating disk 21 for detecting the origin positions of the camshafts 15L and 15R, which will be described later, are provided coaxially and integrally.
The camshaft bracket 16 has a camshaft 15L,
15R, a camshaft drive motor 22 capable of rotating forward and reverse is mounted, and the rotational force of a camshaft drive gear 23 integrated with the camshaft drive motor 22 is applied to the camshaft driven gear 2
A reduction gear group 24 for transmitting to zero is provided rotatably. Further, an origin position detection sensor 25 for detecting a notch formed on the outer peripheral edge of the rotating disk 21 is attached to the base plate 13. When the origin position detecting sensor 25 detects a notch in the rotating disk 21, the distance from the cam shafts 15L and 15R to the upper end surface of the eccentric cam 17 is set to be minimum.

The lower end surfaces of the left and right columns 40 are mounted on the left and right eccentric cams 17, respectively, and these are always kept in contact with each other by a tension spring (not shown). Then, similarly to the embodiment shown in FIGS. 1 to 7, the forward rotation of the camshaft drive motor 22 from the origin position is started, and the eccentric cam 17 is rotated synchronously, whereby the top beam 3
The distance between the ink-jet head 42 of the ink-jet unit 47 attached to the printer 8 and the print surface 41 of the print target 33 on the transport belt 32 can be adjusted to an appropriate distance in a non-contact state.

In the above-described embodiment, the number of parts can be reduced as compared with the previous embodiment by the amount that the elevating table 26 is not necessary. When the weight of the print object 33 and its transport device is increased, the number of parts is smaller. A motor with a driving force can be used. Further, the present invention can be applied to the case where the back surface of the print object 33 abutting on the transport belt 32 and the print surface 43 are parallel to each other, but the transport direction of the transport belt 34 is similar to the embodiment shown in FIGS. It is of course possible to correspond to the print object 33 whose thickness gradually changes along the width direction orthogonal to the print object 33.

FIG. 11 shows a plan structure of another embodiment of the present invention, and FIG. 12 shows a sectional structure taken along the line XII-XII of FIG.
However, since the present embodiment is a combination of the embodiment shown in FIG. 8 and the embodiment shown in FIG. 10, members having basically the same functions as those in the previous embodiment are the same as those in the previous embodiment. The reference numerals are used, and the description is omitted. That is, in this embodiment, when the gap adjusting sensors 51L and 51R are turned on, respectively, the camshaft drive motors 22L and 22R
Are stopped, and when the camshaft drive motors 22L and 22R are further reversed by a predetermined amount, the interval between the print surface 41 of the print target 33 and the inkjet head 42 is set to be an appropriate distance. ing. That is, when the thickness of the print target 33 in the width direction crossing the transport direction of the print target 33 changes in a wedge shape, the position of the gap adjusting sensors 51L and 51R that is located on the thicker side is smaller. Is turned on first, and the one located on the thinner side is later turned on, and the base plate 13 side located on the thinner side rises higher and becomes inclined, so that the printing surface of the printing target is a unit. It is held parallel to the guide rod 44 and the main scanning screw shaft 45.

For this purpose, the upper end of the elevating guide rod 14 is rotatably connected to the lower end of the column 40 via a connecting pin 69, and the lower part of the elevating guide rod 14 is attached to both the front and back surfaces of the base plate 13. It is slidably fitted to the elevating guide tubes 27a, 27b. The connecting pin 69 can move along an arc-shaped long hole 72 formed in the column 40. The column 40 and the top beam 38 are detachably connected to each other via a height adjustment block (not shown) so as to cope with a case where the thickness of the print object 33 exceeds the eccentric amount of the eccentric cams 17L and 17R. Is preferred.

In the above-described embodiment, the printing target 33 is transported by the transport belt 32. However, the weight of the printing target 33 is controlled by the top beam 38 and the column 40 that hold and drive the ink jet unit 47.
When the weight is larger than that of the portion including the components, the top beam 38 and the column 40 on which the inkjet unit 47 is mounted may be conveyed to the base plate 13 so that a motor having a smaller driving force can be used.

FIG. 13 shows the appearance of another embodiment of the present invention. Members having basically the same functions as those of the previous embodiment are denoted by the same reference numerals, and description thereof is omitted. And That is, on both left and right sides of the base plate 13, a column guide rod 73 and a sub-scanning screw shaft 74 are arranged in parallel with each other along the longitudinal direction.
3, a pair of bracket portions 75I formed at both front and rear end portions,
It is held at 75O. In addition, these column guide rods 7
An eccentric cam 17 is integrally formed on a pair of left and right cam shafts 15L, 15R rotatably attached to a pair of front and rear bracket portions 75I, 75O in a manner parallel to the 3 and the sub-scanning screw shaft 74. I have. At the front and rear ends of the lifting table 26 on which the left and right ends are mounted on the eccentric cam 17,
An elevating guide cylinder 27 slidably fitted to an elevating guide bar (not shown) projecting vertically upward from the base plate 13 is provided so as to protrude vertically downward.

The synchronous gears 18 provided at one end of the pair of left and right camshafts 15L, 15R are provided with endless toothed belts so that the rotational phases of the eccentric cams 17 with respect to the camshafts 15L, 15R always coincide. The height from the surface of the base plate 13 to the upper end surface of each eccentric cam 17 is always set to be equal. One camshaft 1
5R, a camshaft drive motor 22 attached to one of the bracket portions 75I, and an origin position detection (not shown) for detecting an origin position at which the distance from the camshafts 15L, 15R to the upper end surface of the eccentric cam 17 is minimized. The sensor is connected.

The column 40L slidably fitted along the column guide rod 73 and the column 40R screwed to the sub-scanning screw shaft 74 are integrally connected via a connection beam 76. A sub-scanning screw shaft 74 is connected to a column drive motor 77 attached to the bracket portion 75O. At one end of the columns 40L and 40R, left and right ends of a unit guide rod 44 and a main scanning screw shaft 45 orthogonal to the column guide rod 73 and the sub-scanning screw shaft 74 are attached, respectively. Left and right end portions of a sensor holder guide bar 49 and a detent bar 55 which are parallel to the unit guide bar 44 and the main scanning screw shaft 45 are attached to the end side.

As a result, the lift table 26 is moved up and down by the operation of the camshaft drive motor 22, and the lift table 2
The print surface 41 of the print object 33 placed on 6
The gap between the inkjet head and the inkjet head (not shown) of the inkjet unit 47 is appropriately adjusted by the gap adjusting sensor 51 mounted on the sensor holder 52. The printing operation proceeds by the vertical movement of the ink jet unit 47 due to the intermittent driving of the column driving motor 77 and the width direction of the ink jet unit 47 driven by the main scanning screw shaft driving motor 46.

As a means for driving the columns 40L and 40R in the vertical direction, a linear pulse motor having a higher responsiveness can be employed.

FIG. 14 shows a plan structure of another embodiment of the present invention. Members having basically the same functions as those of the previous embodiment are denoted by the same reference numerals, and description thereof is omitted. Shall be. That is, a pair of column guide rods 73L, 73R is provided on both left and right sides of the base plate 13 along the longitudinal direction.
Are arranged in parallel with each other, and both ends thereof are
3, a pair of bracket portions 75I formed at both front and rear end portions,
It is held at 75O. In addition, these column guide rods 7
Eccentric cams 17L and 17R are integrally formed on a pair of left and right camshafts 15L and 15R that are rotatably attached to a pair of front and rear bracket portions 75I and 75O in parallel with 3L and 73R. These eccentric cams 17
Elevating table 26 with left and right ends mounted on L, 17R
A connecting pin 69, a connecting portion 70 of the ascending and descending guide rod 14 (both not shown), an ascending and descending guide cylinder 27a, and the like are interposed between the base plate 13 and the front and rear ends as shown in FIG. The lifting table 26 can be tilted to the left and right via the connecting pins.

At one end of each of the camshafts 15L and 15R,
The camshaft drive motors 22L and 22R attached to one bracket portion 75I, respectively, and the camshafts 15L and 1R
An origin position sensor (not shown) for detecting an origin position at which the distance from 5R to the upper end surface of each of the eccentric cams 17L and 17R is minimum is connected. A linear pulse motor 79 having a stator coil 78 laid on the base plate 13 along the column guide rod 73R is interposed between the one column 40R and the base plate 13.

As a result, the elevating table 26 is inclined according to the width of the printing object 33 placed on the elevating table 26 in the width direction, and the printing surface 41 of the printing object 33 is held parallel to the base plate 13. The print surface 41 of the print object 33 and the ink jet unit 4
7, the gap between the gap adjustment sensor 51L mounted on the sensor holder 52 and the gap adjustment sensor 51 mounted on the sub-sensor holder 71.
Adjusted appropriately by R.

In the above-described embodiment, the ink jet unit 47 is caused to scan in the width direction of the print object 33, but the ink discharge ports are arranged over the entire width of the top beam 38 or the connection beam 76. did,
When a so-called full line type ink jet head is used, a mechanism for scanning the ink jet head in the width direction of the print target 33 can be omitted. In the embodiment described above, the eccentric cams 17, 1
Elevating table 2 using 7I, 17O, 17L, 17R
Although the lifting device 6 and the column 40 are moved up and down, it is of course possible to adopt a lifting mechanism having another known structure.

The present invention employs an ink jet head which performs printing by jetting liquid (hereinafter referred to as ink) droplets of ink or paint using thermal energy, particularly among ink jet systems. This provides an excellent effect in an ink jet printing apparatus.

The typical structure and principle are described using, for example, the basic principles disclosed in US Pat. No. 4,723,129 and US Pat. No. 4,740,796. What is performed is preferred. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, the ink droplets are arranged corresponding to the sheet or ink path holding the ink droplets. At least one which provides a rapid rise in temperature beyond nucleate boiling to the electrothermal transducers in response to the print information.
By applying two drive signals, thermal energy is generated in the electrothermal transducer, causing film boiling on the heat-acting surface of the ink jet head, and as a result, ink bubbles corresponding one-to-one to these drive signals are formed. It is effective because it can. The ink is ejected from the ejection port by the growth and contraction of the bubble to form at least one ink droplet. When the driving signal is formed into a pulse shape, the growth and shrinkage of the bubble are immediately and appropriately performed, and therefore, the ejection of the ink droplet having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in U.S. Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in U.S. Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent printing can be performed.

Further, the present invention can be effectively applied to a full-line type ink jet head having a length corresponding to the maximum width of a print object which can be printed by the ink jet printing apparatus. This print head may be one that satisfies the above width by combining a plurality of print heads, or one that satisfies the above width by a single print head.

In addition to this, even in the case of the serial type as in the above-described embodiment, the ink jet head fixed to the apparatus main body, or the electric connection with the apparatus main body or the connection from the apparatus main body by being mounted on the apparatus main body. The present invention is also effective when a replaceable chip-type ink-jet head capable of supplying the above ink or a cartridge-type ink-jet head having an ink tank provided integrally with the ink-jet head itself is used.

Further, it is preferable to add ejection recovery means for the ink jet head, preliminary auxiliary means, and the like as the structure of the ink jet printing apparatus of the present invention since the effects of the present invention can be further stabilized. Specific examples include capping means for the ink-jet head, cleaning means, pressurizing or sucking means, an electrothermal conversion element, a preliminary heating element using another heating element, or a combination thereof. Examples of the heating unit include a preliminary ejection unit that performs ejection different from printing.

The type and number of ink jet heads to be mounted are, for example, not only one provided for a single color ink but also a plurality corresponding to a plurality of inks having different color tones and densities. The number may be provided.

[0082]

According to the ink jet printing method and apparatus of the present invention, the moving means is driven in a direction in which the gap adjustment sensor can contact the printing surface of the printing object, and the gap is adjusted on the printing surface of the printing object. When the sensor abuts, the moving unit is driven in reverse, and the mounting unit of the ink jet unit and the mounting portion of the printing object are relatively moved by a predetermined amount in a direction in which the gap adjustment sensor is separated from the printing surface of the printing object, and printing is performed. After the gap adjustment sensor is brought into a non-contact state from the printing surface of the printing object, the mounting portion of the printing object and the mounting unit of the ink jet unit are relatively moved in a direction parallel to the printing surface of the printing object to move the printing object. Since the specified information is printed on the print surface, it can be applied to the print surface of print objects with different thicknesses. And a printed surface of the ink jet head and the printing object ink jet unit reliably it is possible to hold a predetermined interval, it is possible to achieve good ink jet printing method and apparatus for quality Te.

Even if the object to be printed is a wedge-shaped plate material whose thickness gradually changes along the width direction, the object to be printed is parallel to the scanning surface of the ink jet unit during the printing operation. Since the object placing portion is inclined in the width direction, the printing operation can be performed without any problem.

In addition, during the printing operation, the gap adjustment sensor and the print surface of the printing object are kept in a non-contact state, so that there is no possibility that the print surface is damaged by the gap adjustment sensor.

[Brief description of the drawings]

FIG. 1 is a cutaway side view showing a schematic structure of an embodiment of an inkjet printing apparatus according to the present invention.

FIG. 2 is a plan view of the embodiment shown in FIG.

FIG. 3 is an extracted enlarged sectional view of a part of the ink jet unit of FIG. 1;

FIG. 4 is a perspective view illustrating an appearance of a print target applicable to the embodiment illustrated in FIG.

FIG. 5 is a perspective view illustrating an appearance of another print target applicable to the embodiment illustrated in FIG.

FIG. 6 is a control block diagram of the embodiment shown in FIG. 1;

FIG. 7 is a flowchart showing a procedure of a gap adjusting operation in the embodiment shown in FIG.

FIG. 8 is a plan view illustrating a schematic structure of another embodiment of the inkjet printing apparatus according to the present invention.

9 is a sectional view taken along the line IX-IX in FIG.

FIG. 10 is a plan view illustrating a schematic structure of another embodiment of the inkjet printing apparatus according to the present invention.

FIG. 11 is a plan view illustrating a schematic structure of an ink jet printing apparatus according to another embodiment of the present invention.

12 is a sectional view taken along the arrow XII-XII in FIG.

FIG. 13 is a perspective view illustrating an appearance of a schematic structure of still another embodiment of the inkjet printing apparatus according to the present invention.

FIG. 14 is a perspective view illustrating an appearance of a schematic structure of still another embodiment of the inkjet printing apparatus according to the present invention.

[Explanation of symbols]

 Reference Signs List 11 mounting surface 12 pedestal 13 base plate 14 elevating guide rod 15I, 15O, 15L, 15R camshaft 16 camshaft bracket 17, 17L, 17R eccentric cam 18 synchronous gear 19 toothed belt 20 camshaft driven gear 21 rotating disk 22 , 22L, 22R Camshaft drive motor 23 Camshaft drive gear 24 Reduction gear group 25, 25L, 25R Home position detection sensor 26 Elevation table 27, 27a, 27b Elevation guide cylinder 28 Tension spring 29I, 29O Pulley shaft 30 Pulley shaft bracket 31 Belt pulley 32 Conveying belt 33 Print target 34 Pulley shaft drive motor 35 Pulley shaft drive gear 36 Pulley shaft driven gear 37 Reduction gear 38 Top beam 39 Height adjustment block 40, 40L, 40R Column 41 Print surface 42 Inkjet head 43rd Determining pin 44 Unit guide rod 45 Main scanning screw shaft 46 Main scanning screw shaft drive motor 47 Inkjet unit 48 Guide rod support arm 49 Sensor holder guide rod 50 Medium leading end detection sensor 51, 51L, 51R Gap adjusting sensor 52 Sensor holder 53 Stop Screw 54 Detent groove 55 Detent rod 56 Swing lever 57 Pivot pin 58 Tension spring 59 Sensor switch 60 Print control circuit 61 Power supply circuit 62 Power supply unit 63 Gap adjustment circuit 64 Personal computer 65 Interface board 66 Sensor detection circuit 67 Print Switch 68 clearance adjustment start switch 69 connecting pin 70 connecting part 71 auxiliary sensor holder 72 long hole 73 column guide rod 74 auxiliary scanning screw shaft 75I, 75O bracket part 76 connecting beam 77 column drive Dynamic motor 78 Stator coil 79 Linear pulse motor

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-5183 (JP, A) JP-A-6-155853 (JP, A) JP-A-3-97579 (JP, A) JP-A-63-1988 256473 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/01 B41J 25/308 B41M 5/00

Claims (12)

(57) [Claims] 1. A print target mounting portion on which a print target is mounted, an ink jet unit mounting portion to which an ink jet head facing the print target is mounted, and a conveying means for conveying the print target mount portion. And the method of transporting the print object placing section by the transport means.
The printing object mounting portion is arranged along the width direction orthogonal to the
Moving means but for the the mounting portion of the ink jet unit so as to tilt with said print object placement unit is moved relative to these opposing direction, the width direction on the mounting portion side of the ink jet unit
Multiple provided along the direction, the inkjet printing method for printing predetermined information on the printing surface of said printing object by using an ink jet printing apparatus and a clearance adjustment sensor each may contact the print surface of the printed object A first driving unit that drives the moving unit in a direction in which the gap adjustment sensor can abut on the print surface of the print target, and makes the gap adjustment sensor abut on the print surface of the print target. A moving step, when the gap adjustment sensor is brought into contact with the print surface of the print object, the moving unit is driven in reverse, in a direction in which the gap adjustment sensor is separated from the print surface of the print object. The mounting portion of the ink jet unit and the printing object placement portion are relatively moved by a predetermined amount. A second moving step, the printing of the state where the gap adjusting sensor from the printing surface is spaced a predetermined amount of print object, wherein the printed object and a mounting portion of the printed object placement unit and ink jet unit comprising a step of printing predetermined information on a plane parallel to the direction moved relative to the printing surface of the printing object, the second mobile stearate
The print pair from the first moving step
The plurality of gap adjustment sensors with respect to the printed surface of the elephant.
Based on the contact result of the
The object to be printed is tilted along the width direction.
An ink jet printing method characterized by moving a mounting portion . 2. A print pair on which an object to be printed is placed.
The elephant mounting part and the inkjet head facing the print target are
Attachment part of inkjet unit to be attached
When the conveying means for conveying the printing object placing section, the a mounting portion of the ink jet unit purine
Relative to the object placement section in the facing direction
Moving means, and the transfer to the mounting unit side of the inkjet unit
Orthogonal to the transport direction of the printing object placing section by means
The print is provided movably along the width direction
A gap adjustment sensor capable of contacting the print surface of the object;
Using an inkjet printing apparatus having
Event to print the specified information on the print surface of the
Ink jet printing method, wherein the gap adjustment section is provided on the printing surface of the printing object.
The moving means is driven in a direction in which the
Place the gap adjustment sensor on the print surface of the lint target
Abutting; and a gap adjusting section on the printing surface of the printing object.
When the sensor is brought into contact, the moving means is driven in reverse,
From the print surface of the printing object,
Remove the inkjet unit in the direction that the sensor moves away.
The mounting part and the printing object placing part are relatively moved by a predetermined amount.
A step of, the clearance adjustment from the printed surface of the printed object
With the sensor separated by a predetermined distance, place the print object
Part and the mounting part of the ink jet unit
Relative movement in a direction parallel to the print surface
Information on the printing surface of the printing object.
Lee, characterized in that it comprises the step of printing the
Ink jet printing method. Wherein said moving means according to claim 1 or claim, characterized in that said print object placing section it is capable of relative translation in the opposite direction of the mounting portion of the ink jet unit 2. The inkjet printing method described in 2 . 4. A lever having one end protruding toward the printing surface of the printing object, the gap adjustment sensor including:
There is provided an urging means for urging one end of the lever toward the printing surface of the printing object, and a switch for detecting a predetermined displacement or more of the other end of the lever against the urging means. The inkjet printing method according to claim 1, wherein the inkjet printing method is used. 5. The method according to claim 1, further comprising the step of driving the moving unit to set a predetermined interval between the mounting unit of the inkjet unit and the print object placement unit, thereby setting the mounting unit of the inkjet unit and the printing unit. The moving means is driven in a direction in which the gap adjustment sensor can abut on the print surface of the print target from a state in which the target mount is set at the predetermined interval. Claim 1 or Claim 2
Alternatively, the inkjet printing method according to claim 3 or 4 . 6. A printing object mounting portion on which a printing object is mounted, and provided so as to be relatively movable in a direction facing the printing object mounting portion, and may face a printing surface of the printing object. Attachment section of an inkjet unit to which an inkjet head is attached, transport means for transporting the print object placement section, and transport method of the print object placement section by the transport means
The printing object mounting portion is arranged along the width direction orthogonal to the
Moving means but for the the mounting portion of the ink jet unit so as to tilt with said print object placement unit is moved relative to these opposing direction, the width direction on the mounting portion side of the ink jet unit
Each movably provided in plural along the direction, said the clearance adjustment sensor each may contact with the printed surface of the printed object, a direction in which the clearance adjustment sensor on the printed surface of the printed object may contact A direction in which the moving means is driven, and the moving means is driven in reverse when the gap adjustment sensor comes into contact with the print surface of the print object, and the gap adjustment sensor moves away from the print surface of the print object. Control means for relatively moving a mounting portion of the inkjet unit and the mounting portion of the printing target relative to each other by a predetermined amount, and a mounting portion of the mounting portion of the printing target and the mounting portion of the inkjet unit and the printing surface of the printing target An ink jet printing apparatus, comprising: scanning means for relatively moving in a parallel direction. 7. A print pair on which an object to be printed is placed.
Relative movement is possible in the direction opposite to the elephant mounting part and this printing object mounting part
And the printing surface of the printing object
Ink to which a compatible inkjet head is attached
A mounting unit for the jet unit, a transport unit for transporting the printing object placement unit, a mounting unit for the inkjet unit, and the printing unit.
Relative to the object placement section in the facing direction
Moving means, and the transfer to the mounting unit side of the inkjet unit
Orthogonal to the transport direction of the printing object placing section by means
The print is provided movably along the width direction
A gap adjustment sensor capable of contacting the print surface of an object
The gap adjustment section on the printing surface of the printing object.
The moving means is driven in a direction in which the
The gap adjustment sensor is provided on the print surface of the printing object.
At the point of contact, the moving means is driven in reverse to
The gap adjustment sensor is separated from the print surface of the target object.
Mounting part of the inkjet unit in the direction of
A system for relatively moving the printing object mounting portion by a predetermined amount.
Control means, the printing object mounting portion and the ink jet unit.
The mounting portion and the printing surface of the printing object and
That comprises a scanning means for relatively moving in a direction parallel to
Characteristic inkjet printing device. Wherein said moving means according to claim 6 or claim, characterized in that said print object placing section it is capable of relative translation in the opposite direction of the mounting portion of the ink jet unit 8. The inkjet printing apparatus according to 7 . 9. A lever having one end protruding toward the printing surface of the print target, the gap adjustment sensor including:
There is provided an urging means for urging one end of the lever toward the printing surface of the printing object, and a switch for detecting a predetermined displacement or more of the other end of the lever against the urging means. 7. The method according to claim 6, wherein
Ink-jet printing apparatus according to claim 7 or claim 8. 10. An ink jet printer according to claim 1, further comprising: an initial setting unit configured to set a predetermined interval between the mounting unit of the ink jet unit and the print object placement unit. And driving the moving means in a direction in which the gap adjustment sensor can contact the print surface of the print object from a state in which the unit and the print object mounting portion are set at a predetermined interval. Claim 6
An inkjet printing apparatus according to claim 7, claim 8, or claim 9 . 11. The ink jet printing apparatus according to claim 10, wherein said initial setting means is an origin position detecting sensor for holding a mechanical position of said moving means at a predetermined position. 12. The ink-jet head according to claim 1, wherein the ink-jet head uses thermal energy to generate bubbles in the ink, and discharges the ink based on the bubbles.
Inkjet printing apparatus according to 6 or claim 7 or claim 8 or claim 9 or claim 10 or claim 1 1.