JP2001205794A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer which can print easily on the outer circumferential surface of a print object such as a columnar body, by means of an ink jet head. SOLUTION: In the ink jet printer 1, a print object, i.e., a columnar body 4, is clamped horizontally between a fixed side holding disc 51 and a movable side holding disc 52 constituting a holding mechanism 5. The gap between the outer circumferential surface 4a of the columnar body 4 and an ink jet head 33 disposed oppositely thereto can be adjusted by means of a gap adjusting mechanism 39. A rotary drive mechanism 6 for rotating the columnar body 4 comprises a variable speed drive 63 which can be regulated to regulate the circumferential speed of the columnar body 4, i.e., the relative speed to the ink jet head 33. Consequently, the outer circumferential surface of columnar bodies having different outer diametral dimensions can be printed with high quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer, and more particularly to an ink jet printer having a structure suitable for printing on the surface of a column, a sphere, or the like.

[0002]

2. Description of the Related Art Ink jet printers are widely used as output devices for personal computers and the like, and record various images processed by a personal computer or various images captured through a digital camera or the like on recording paper. It is very convenient because it can be played back.

[0003]

Here, the object to be printed by the ink jet printer is generally a flat recording sheet, but it is convenient if printing can be performed on a three-dimensional object. In particular, it is convenient if printing can be performed on a circular outer peripheral surface of an object such as a cylinder or a sphere with the same ease as printing on a flat surface.

[0004] In view of the above, an object of the present invention is to propose an ink jet printer capable of performing printing on the surface of a cylinder or a sphere by an ink jet head.

[0005]

In order to solve the above-mentioned problems, an ink jet printer according to the present invention comprises a holding means for holding a printing object and a printing object held by the holding means. In a typical case, a rotating means for rotating around a certain rotation center line, and an inkjet head for performing printing on the outer peripheral surface of the printing object,
And a head supporting means for supporting the ink jet head.

Here, it is desirable to have peripheral speed adjusting means for adjusting the peripheral speed of the printing object rotated about the rotation center axis by the rotating means.

In the ink jet printer of the present invention, printing is performed on the surface of the printing object by the ink jet head disposed at a fixed position while rotating the printing object. Therefore, when the printing target is a cylinder, a sphere, or the like, an image similar to the case where printing is performed on the outer peripheral surface on a flat surface can be reproduced. Further, since the transport speed of the printing target passing through the inkjet head, that is, the peripheral speed thereof is adjustable, the printing target can be always rotated at an appropriate speed, and therefore, an appropriate image can always be reproduced. .

Here, when the object to be printed is a rotationally symmetric object, the holding means holds the object to be printed from both sides in a state where the rotationally symmetric axis of the object to be printed coincides with the rotation center line. What is necessary is just to be a structure.

Next, when printing is performed on the surface of a general recording paper in the form of a cylinder, the holding means includes a rotary cylinder having a circular outer peripheral surface or a conical outer peripheral surface, A holding arm that holds both ends of the rotating cylinder, the rotating means is configured to rotate the rotating cylinder held by the holding arm around its central axis, and on the outer periphery of the rotating cylinder, What is necessary is just to wind a recording paper as a printing object.

On the other hand, when the diameter or the like of the printing object changes,
The gap between the print target and the inkjet head changes, and there is a possibility that an appropriate print cannot be formed. In order to avoid such an adverse effect, the head support unit includes a gap adjusting unit that adjusts a gap between the outer peripheral surface of the printing target held by the holding unit and the nozzle surface of the inkjet. It is desirable that

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an ink jet printer to which the present invention is applied will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of the ink jet printer of the present embodiment, and FIG. 2 is an explanatory diagram showing a part of the printer. Referring to these drawings, the ink jet printer 1 of the present embodiment includes an apparatus mount 2 (head supporting means), an ink jet head unit 3 attached to the apparatus mount 2, and a cylindrical body 4 to be printed. And a rotation drive mechanism 6 for rotating the columnar body 4 held by the holding mechanism 5.

The ink jet head unit 3 has a horizontally long unit case 31 to which a guide shaft 32 extending in the sub-scanning direction (print width direction) is attached. A carriage 34 carrying 33 is supported so as to be able to reciprocate in the sub-scanning direction. Carriage 3
Numeral 4 is connected to a timing belt 37 extending between a pair of pulleys 35 and 36, and one pulley 36 is rotated by a carriage drive motor 38.

When the pulley 36 is rotated by driving the motor 38, the timing belt 37 moves. Therefore, the ink jet head 33 carried on the carriage 34 connected to the timing belt 37 can be reciprocated in the sub-scanning direction. it can. Ink is supplied to the inkjet head 33 from an ink supply source (not shown). Each of the ink nozzles of the inkjet head 33 is driven by a driving device (not shown) in synchronization with the movement of the carriage 34, and ink droplets are formed. Is discharged, and a desired print can be formed on the surface of the printing object.

Here, the ink jet head unit 3 of this embodiment is supported so as to be able to move up and down with respect to the apparatus gantry 2, and the height position thereof can be adjusted by a gap adjusting mechanism 39. The gap adjusting mechanism 39 includes, for example, a rack 391 and a pinion 392, and
3 is converted into a vertical movement of the unit 3. Since the ink nozzle surface 33a of the ink jet head 33 of this embodiment is directed downward, when the ink jet head unit 3 is moved up and down by the gap adjusting mechanism 39, the ink nozzle surface 33a and the outer peripheral surface of the cylindrical body 4 which is a printing object are formed. The gap G of 4a can be adjusted.

The holding mechanism 5 for holding the cylindrical body 4 includes:
A fixed holding disk 51 and a movable holding disk 52 facing each other coaxially from both sides in the sub-scanning direction are provided, and the columnar body 4 is sandwiched between them. Fixed side holding disk 5
1 is coaxially fixed to the tip of the rotating shaft 61. On the other hand, the movable-side holding disk 52 is rotatably mounted coaxially on the distal end of the telescopic rod 54 of the cylinder 53. The cylinder 53 is attached to the apparatus gantry 2, and its telescopic rod 54 is extendable along a rotation center line 5 a connecting the centers of the disks 51 and 52.

Therefore, the cylinder 53 is driven to move the movable-side holding disk 52 away from the fixed-side holding disk 51,
When the distance between them is widened and the cylinder 53 is driven to move the movable-side holding disk 52 in the direction approaching the fixed-side holding disk 51 while the columnar body 4 is held horizontally, the distance between the disks 51 and 52 is increased. The cylindrical body 4 can be held between them. If the center axis of the cylinder 4 is held so as to coincide with the rotation center line 5a, the cylinder 4 can be rotated around the center axis by the rotation drive mechanism 6 described below.

The rotation drive mechanism 6 includes a rotation shaft 61 on which the fixed holding disk 51 is attached at the tip as described above,
A drive motor 62 serving as a rotation drive source and a transmission 63 for reducing the rotation of the motor and transmitting it to the rotation shaft 61 are provided. The transmission 63 of this example is a continuously variable transmission, and includes a V belt 64,
This is provided with a driving pulley 65 and a driven pulley 66 which are bridged. The drive-side pulley 65 is composed of a pair of left and right pulley pieces, and the outer diameter of a V-shaped annular groove formed between them for bridging the V-belt can be increased or decreased. The driving pulley 65 is connected to the output shaft of the motor 62, and the driven pulley 66 is connected to the rotating shaft 61. The rotating shaft 61 is supported horizontally so as to be rotatable with respect to the apparatus gantry 2.

The rotation driving mechanism 6 is driven to rotate the rotation shaft 61.
Is rotated, the cylindrical body 4 held between the fixed-side holding disk 51 attached to the tip and the other movable-side holding disk 52 can be rotated. The rotational speed of the cylindrical body 4 or its peripheral speed is controlled by the continuously variable transmission 6.
By changing the speed ratio of No. 3, it is possible to adjust the speed to an appropriate speed.

The rotating shaft 61 of this embodiment has a rotating disk 67
Is mounted therein, and a slit 68 for finding the origin is formed at one position in the circumferential direction. By detecting this slit by the optical origin sensor 69, the origin position of the rotation start can be always set to a fixed position.

The printing operation of the ink jet printer 1 according to the present embodiment having the above-described configuration will be described. As aforementioned,
The space between the fixed-side holding disk 51 and the movable-side holding disk 52 is widened, and the columnar body 4 to be printed is sandwiched between them so as to be horizontal. At this time, the cylinder 4 is attached so that the center axis of the cylinder 4 coincides with the rotation center line 5a.

Next, a gap G between the ink nozzle surface 33a and the outer peripheral surface 4a of the held cylindrical body 4 is set to an appropriate value by the gap adjusting mechanism 39. Further, the continuously variable transmission 63 is adjusted so that the peripheral speed of the cylindrical body 4 becomes a speed suitable for printing.

After the adjustment, the ink jet head 33 is driven while the rotary drive mechanism 6 is driven to rotate the cylindrical body 4, and printing is formed on the surface of the cylindrical body. The printing start position in the rotation direction is controlled based on the output of the origin sensor 69. After printing is completed, the cylinder 4 is removed from the holding mechanism 5.

Here, when printing on another cylinder, if the outer diameter of the cylinder is different, the gap G with the nozzle surface of the ink jet, the peripheral speed of the cylinder (relative rotation speed with respect to the ink jet head) May be different, and an appropriate print may not be formed on the surface of the cylindrical body. However, in this example, as described above, the gap adjusting mechanism 39
In addition, since the continuously variable transmission 63 for adjusting the peripheral speed is provided, it is possible to always perform appropriate printing on the outer peripheral surface of the cylindrical bodies having different outer diameters. (Other Embodiments) In the above example, the printing target is a cylindrical body. However, the present invention relates to a printing target having a truncated cone shape as shown in FIG. Similarly, printing can be performed on the outer peripheral surface of a spherical printing object as shown in (1).

Further, in the above example, the printing target is held horizontally, but a configuration in which the printing target is held vertically and an ink jet head is arranged so as to face the printing target may be employed.

Furthermore, the present invention can be applied to an ink jet printer for printing on recording paper wound in a cylindrical or frustoconical shape. In this case, as the holding mechanism 5, a configuration in which a cylindrical or frustoconical recording paper holding cylinder (rotary cylinder) is attached between the disks 51 and 52 (holding arms) is adopted. The recording paper may be wound around the outer peripheral surface and fixed, and in this state, printing may be performed on the surface of the cylindrical recording paper while rotating the recording paper.

The gap adjusting mechanism 39, the holding mechanism 5, the rotary drive mechanism 6, and the peripheral speed adjusting mechanism (6
As a matter of course, instead of 3), a mechanism having another configuration and capable of realizing the same operation and effect as the existing one may be adopted.

[0028]

As described above, the ink jet printer of the present invention holds the cylindrical or frusto-conical print object by the holding means, and rotates the print object by the rotation driving means while rotating the print object by the rotation driving means. To print on the outer peripheral surface. Therefore, printing can be easily performed on the circular outer peripheral surface.

Further, according to the present invention, since the gap adjusting mechanism and the peripheral speed adjusting means for adjusting the peripheral speed (relative speed with respect to the ink jet head) of the printing object are provided, the outer peripheral surfaces of the printing objects having different sizes are provided. Also, high quality printing can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of an inkjet printer to which the present invention has been applied.

FIG. 2 is an explanatory view showing a part of the inkjet printer shown in FIG. 1;

FIG. 3 is an explanatory diagram illustrating another example of a print target.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink-jet printer 2 Device stand 3 Ink-jet head unit 33 Ink-jet head 33a Ink nozzle surface 39 Gap adjusting mechanism 4 Printed object 4a Outer peripheral surface 5 Holding mechanism 5a Rotation center line 51 Fixed-side holding disk 52 Movable-side holding disk 53 Cylinder 6 Rotary drive Mechanism 61 Rotary shaft 62 Motor 63 Continuously variable transmission

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EA09 EC11 EC12 EC31 EC33 FA02 FA10 FB01 FB09 FC06 HA27 2C058 AB17 AC07 AE09 AF29 BA01 BA17 2C062 RA01 RA06 2C064 CC04 CC05 CC13 DD02 DD05 DD14

Claims (6)

[Claims] 1. A holding unit for holding a printing target, a rotating unit for rotating the printing target held by the holding unit, an inkjet head for printing on an outer peripheral surface of the printing target, An ink-jet printer comprising: a head supporting means for supporting the ink-jet head. 2. The ink-jet printer according to claim 1, wherein the rotating unit rotates the printing object held by the holding unit around a fixed rotation center line. 3. The ink jet printer according to claim 2, further comprising a peripheral speed adjusting unit that adjusts a peripheral speed of a printing target object that rotates about the rotation center axis by the rotating unit. 4. The printing object according to claim 3, wherein the object to be printed is a rotationally symmetric body, and the holding means holds the printing symmetrical object on both sides in a state where the rotationally symmetric axis of the printing symmetrical object coincides with the rotation center line. An inkjet printer characterized in that it is sandwiched from above. 5. The rotating means according to claim 3, wherein the holding means includes a rotating cylinder having a circular outer peripheral surface or a conical outer peripheral surface, and holding arms for holding both ends of the rotating cylinder. For rotating the rotary cylinder held by the holding arm around a central axis thereof, wherein a recording paper as a printing target is wound around the outer circumference of the rotary cylinder. . 6. The head support unit according to claim 1, wherein the head support unit adjusts a gap between an outer peripheral surface of a print target held by the holding unit and a nozzle surface of the inkjet. An ink jet printer, comprising: a gap adjusting unit that performs the operation.