JP4159037B2 - UV irradiation mechanism for inkjet printer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, UV (ultra-violet) irradiation means that travels with an inkjet head irradiates ultraviolet curable ink droplets that are ejected from the inkjet head and land on the surface of the media, and then the ink droplets are dried. The invention relates to a UV irradiation mechanism for an inkjet printer to be cured.
[0002]
[Prior art]
As shown in FIG. 3, the ink droplets are ejected from the nozzles 12 arranged on the lower surface of the inkjet head while the inkjet head 10 travels in the left-right direction above the platen 20, and the ink droplets are mounted on the platen 20. 2. Related Art Inkjet printers are well known in which dots are landed on the surface of the medium 30 and a picture or character comprising an array of a plurality of ink dots is printed on the surface of the medium 30.
As the ink jet printer, there is a type of printer that ejects ultraviolet curable ink droplets from nozzles 12 arranged on the lower surface of the ink jet head as shown in FIG. The printer that ejects the ultraviolet curable ink droplets is provided with UV irradiation means 50 that travels in the left-right direction above the platen 20 together with the inkjet head 10. Then, ultraviolet rays are ejected from the nozzles 12 on the lower surface of the ink jet head through the window 52 on the lower surface of the UV irradiation means to irradiate the ink droplets landed on the surface of the medium 30, thereby drying and curing the ink droplets at an early stage. Then, the ink droplet is prevented from penetrating into the medium 30 portion around the landing location, and the ink droplet is fixed on the surface of the medium 30 in the form of small dots. A clear picture or character composed of a plurality of ink dots without bleeding can be printed on the surface of the medium 30.
[0003]
In the ink jet printer having such a configuration, the UV irradiation unit 50 is provided with a shutter 54 that opens and closes the window 52 on the lower surface of the UV irradiation unit, and a shutter opening and closing unit 56 that drives the shutter 54 to open and close. Then, as indicated by a solid line in FIG. 3, the UV irradiation means 50 and the inkjet head 10 are stopped from traveling, and the UV irradiation means 50 is put on standby at a standby position 70 of the UV irradiation means such as above the side of the platen 20. In this case, the window 52 on the lower surface of the UV irradiation means is closed by the shutter 54 to prevent ultraviolet rays from being emitted outside the UV irradiation means 50. Further, as shown by the broken lines in FIG. 3, when the UV irradiation means 50 and the inkjet head 10 are started to run, the shutter 54 that closes the window 52 on the lower surface of the UV irradiation means is opened, and UV irradiation is performed. The surface of the medium 30 is irradiated with ultraviolet rays from the window 52 on the lower surface of the means.
The UV irradiation means 50 is an air cooling means having an air circulation duct or the like for sending air into the UV irradiation means 50 having a built-in UV lamp 58 that generates high heat and cooling the inside of the UV irradiation means 50. (Not shown) is attached. Then, as shown by a solid line in FIG. 3, when the UV irradiation means 50 is made to stand by at the travel standby portion 70 of the UV irradiation means such as above the side of the platen 20, the air cooling means causes the lower surface of the UV irradiation means to be The window 52 is closed by the shutter 54, and the inside of the UV irradiation means 50, which is heated by heat generated by the lit UV lamp 58, is air-cooled.
As shown by a broken line in FIG. 3, when the UV irradiation unit 50 starts to travel, the shutter 54 that closes the window 52 on the lower surface of the UV irradiation unit is opened, and the lower surface of the UV irradiation unit 50 is opened. Since the outside air enters the UV irradiation means 50 through the window 52 and the inside of the UV irradiation means 50 is cooled by the outside air, there is no need to forcibly cool the inside of the UV irradiation means 50 by the air cooling means.
[0004]
[Problems to be solved by the invention]
By the way, in order for the UV irradiation means 50 to run in the left-right direction above the platen 20 together with the inkjet head 10, it is desirable to suppress the inertia, that is, the weight of the UV irradiation means 50 as small as possible.
This is because if the weight of the UV irradiation means 50 is large, a drive mechanism (not shown) such as a drive motor that causes the UV irradiation means 50 to travel with the inkjet head 10 becomes large, and the cost of the printer increases accordingly. Because it ends up. In addition, the inkjet head 10 cannot be accurately and quickly moved in the left-right direction together with the UV irradiation means 50. This is because the printing speed and printing accuracy of the printer are reduced.
[0005]
As a measure for solving such a problem, it is conceivable that the power source for turning on the UV lamp 58 of the UV irradiation means is turned ON / OFF in accordance with the stoppage of travel of the UV irradiation means 50 and the start of travel. And the method of stopping the ultraviolet irradiation by the UV irradiation means 50, or restarting the ultraviolet irradiation by the UV irradiation means 50 can be considered. A method of eliminating the shutter 54 and the shutter opening / closing means 56 for opening / closing the window 52 on the lower surface of the UV irradiation means when the UV irradiation means 50 is stopped or started is considered. At the same time, a method is conceivable in which the UV lamp 58 that emits high heat is frequently turned off to prevent the inside of the UV irradiation means 50 from becoming hot due to the heat generated by the UV lamp 58 being turned on. And the method of canceling attaching the air cooling means for air-cooling the inside of the UV irradiation means 50 to the UV irradiation means 50 can be considered.
[0006]
However, in such a case, it takes a long time to resume the ultraviolet irradiation by the UV irradiation means 50 after the ultraviolet irradiation by the UV irradiation means 50 is stopped. The reason is that when the UV lamp 58 of the UV irradiation means is turned off and then turned on again, the UV lamp 58 must be cooled to room temperature. This is because it takes about 10 minutes for the extinguished UV lamp 58 to cool to room temperature. Also, it takes about 5 minutes to wait until the UV lamp 58 is once turned off and then turned on again.
[0007]
Further, as a measure for solving the above-described problems, the UV lamp 58 of the UV irradiation unit is continuously turned on regardless of whether the UV irradiation unit 50 is stopped or started and the window 52 on the lower surface of the UV irradiation unit is turned on. A method of continuously radiating ultraviolet rays to the outside of the UV irradiation means 50 can be considered. A method of eliminating the shutter 54 and the shutter opening / closing means 56 for opening / closing the window 52 on the lower surface of the UV irradiation means when the UV irradiation means 50 is stopped or started is considered. At the same time, the window 52 on the lower surface of the UV irradiation means is kept open widely so that the outside air can always smoothly enter inside the UV irradiation means 50, and the UV irradiation means 50 is heated by the heat generated by the UV lamp 58 during lighting. A method for preventing the inside from becoming hot is conceivable. And the method of canceling attaching the air cooling means for air-cooling the inside of the UV irradiation means 50 to the UV irradiation means 50 can be considered.
However, in such a case, when the travel of the UV irradiation means 50 is stopped and the UV irradiation means 50 is put on standby at the travel standby point 70 of the UV irradiation means such as above the side of the platen 20, The portion of the printer that is exposed to ultraviolet rays emitted from the window 52 on the lower surface of the UV irradiation means is heated to a high temperature. Then, the dimensional accuracy of the printer part is out of order, or the mechanical parts of the printer part are damaged due to excessive heat.
[0008]
The present invention has been made in view of such problems, and by eliminating the shutter, shutter opening / closing means and air cooling means from the UV irradiation means, the UV irradiation means can be reduced in weight and the UV lamp can be kept on. UV light emitted from the window on the lower surface of the UV irradiation means hits the printer part near the standby position of the UV irradiation means for stopping the running of the UV irradiation means to prevent the printer part from being heated to a high temperature. It is an object of the present invention to provide a UV irradiation mechanism (hereinafter referred to as a UV irradiation mechanism) for an inkjet printer.
[0009]
[Means for Solving the Problems]
In order to achieve such an object, the UV irradiation mechanism of the present invention comprises:
A travel stand-by point where the travel of the UV irradiating unit is suspended and waited is provided outside the end of the platen in the left-right direction, and when the UV irradiating unit is located at the travel stand-by point, immediately below the window of the UV irradiating unit A cover member is provided at the standby position, and a passage space is formed in the cover member to surround the inner surface opposite to the outer surface facing the window, and the platen in the left-right direction External air is introduced into the passage space from one end opening that opens to the opposite side, and the air is discharged outside through the other end opening that opens to the opposite side to the platen in the left-right direction through the passage space. An air cooling means is provided, and the cover member heated by the UV means located at the standby position is cooled by the air flowing through the passage space.
[0010]
In the UV lamp mechanism having such a configuration, the UV irradiation means that travels in the left-right direction over the platen together with the ink jet head is stopped, and the UV irradiation means is placed in the standby position of the UV irradiation means such as above the side of the platen. When waiting, the window on the lower surface of the UV irradiating means can be covered with a cover arranged immediately below the travel standby position of the UV irradiating means. Then, it is possible to prevent the ultraviolet rays from being emitted from the window on the lower surface of the UV irradiation means that has been waiting at the travel standby location, the ultraviolet rays hitting the nearby printer portion, and the printer portion being heated to a high temperature. .
In this case, air can be forcedly circulated by the air cooling means along the inner part of the cover opposite to the UV irradiation means side of the cover that covers the window on the lower surface of the UV irradiation means. And the cover which is heated by the ultraviolet rays radiated from the window on the lower surface of the UV irradiation means by the air can be continuously cooled so as not to reach a high temperature.
Further, since the cover and the air cooling means are separated from the UV irradiation means and are provided immediately below the traveling standby position of the UV irradiation means, the cover and the air cooling means are provided integrally with the UV irradiation means. Therefore, the UV irradiation means can be reduced in weight.
[0011]
In the UV irradiation mechanism of the present invention, a passage space surrounding the inner surface opposite to the outer surface facing the window is formed in the cover member, and the one end side opening that opens to the opposite side of the platen in the left-right direction is formed. Air cooling means is provided for introducing external air into the passage space and discharging the air to the outside through the other end side opening through the passage space to the side opposite to the platen in the left-right direction.
For this reason, the air that is forcedly circulated along the inner part of the cover by the air cooling means leaks to the periphery of the inkjet head that has been stopped and waited with the UV irradiation means near the running standby position of the UV irradiation means. Can be prevented from being put out. And by the air leaking to the peripheral part of the inkjet head, the dust existing in the peripheral part of the inkjet head is rolled up in the air and attached to the nozzles arranged on the lower surface of the inkjet head, or receives the wind pressure of the air, from or break a meniscus of ink formed in the nozzle tip arranged on the ink jet head lower surface, it is Ki de prevented, from becoming impossible accurately ejecting ink droplets from nozzles arranged on the lower surface Lee inkjet head, to prevent Can do.
[0012]
In UV irradiation mechanism of the present invention may extend from the inner surface of the window opposite to the outer surface opposite the said cover member in the passage space, it may be extending cooling fins.
Such a case, the cooling fins is extended from the inner surface of the cover member, the air to be by Ri forced circulation air cooling means, it is possible to apply blown wide surface area. And it becomes possible to continue cooling a cover member efficiently through the cooling fin with the large surface area.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 show a preferred embodiment of the UV irradiation mechanism of the present invention. FIG. 1 is a schematic structural explanatory diagram of an ink jet printer equipped with the UV irradiation mechanism. FIG. 2 is a schematic structural description of the UV irradiation mechanism. FIG. The UV irradiation mechanism will be described below.
[0014]
In this UV irradiation mechanism, the travel standby position of the UV irradiation means that travels in the left-right direction over the platen 20 together with the inkjet head 10 (the position where the travel of the UV irradiation means 50 is stopped and the UV irradiation means 50 is made to wait) 70. A cover 60 that covers the window 52 on the lower surface of the UV irradiation means that emits ultraviolet rays is disposed on the side of the platen 20 that is directly below, separately from the UV irradiation means 50.
The cover 60 has a flat rectangular cylindrical shape, and the entire upper surface of the window 52 on the lower surface of the UV irradiation means can be covered with a slight gap in the vertical direction by the flat upper surface of the cover 60. Has a structure.
Further, air is forcibly circulated along the inner portion of the cover 60 opposite to the UV irradiation means 50 side of the cover 60 covering the window 52 on the lower surface of the UV irradiation means, and the cover 60 is cooled by the air. A means 80 is provided separately from the UV irradiation means 50.
The air cooling means 80 forcibly sucks air from one opening of the cover 60 having a flat rectangular cylindrical shape, circulates the air inside the cover 60, and then uses the air to open the other opening of the cover 60. It has a structure that discharges from the part. A duct 82 is connected to the other opening of the cover 60, and an intake fan 84 is attached to the tip of the duct 82. Then, by rotating the intake fan 84, the air can be forcibly sucked into the cover 60 from the one opening. Then, the air is circulated inside the cover 60 so as to be discharged from the other opening of the cover 60 to the inside of the duct 82. Then, the air can be released into the atmosphere from the end of the duct 82 through the inside of the duct 82.
[0015]
The rest of the configuration is the same as that of the ink jet printer provided with the conventional UV irradiation mechanism shown in FIG. 3. When using the ink jet printer provided with the UV irradiation mechanism having such a configuration, the solid line in FIG. As shown in FIG. 6, the UV irradiation means 50 that causes the inkjet head 10 to travel in the left-right direction over the platen 20 is stopped, and the UV irradiation means 50 is moved to the travel standby position 70 of the UV irradiation means above the side of the platen 20. When waiting, the entire surface of the window 52 on the lower surface of the UV irradiating means is covered with the flat upper surface of the cover 60 disposed immediately below the traveling standby portion 70 of the UV irradiating means.
Then, it is possible to prevent the cover 60 from radiating ultraviolet rays to the outside of the UV irradiation means 50 from the window 52 on the lower surface of the UV irradiation means that is waiting at the travel standby point 70 of the UV irradiation means. And it can prevent that the ultraviolet-ray radiated | emitted from the window 52 of the UV irradiation means lower surface hits the printer part of the vicinity, and the printer part is heated to high temperature.
At that time, the air cooling means 80 forcibly circulates air along the inner part of the cover 60 opposite to the UV irradiation means 50 side of the cover 60 covering the window 52 on the lower surface of the UV irradiation means. Specifically, the intake fan 84 is rotated to forcibly suck air from one opening of the cover 60 and circulate through the inside of the cover 60, and then the air is passed through the other opening of the cover 60. To exhale. Then, the discharged air passes through the inside of the duct 82 and is released from the tip of the duct 82 into the outside air.
Then, the cover 60 heated by the ultraviolet rays radiated from the window 52 on the lower surface of the UV irradiation means can be cooled by the air circulating inside the cover 60 so as not to reach a high temperature.
[0016]
In this UV irradiation mechanism, the air that is forced to circulate along the inner portion of the cover 60 by the air cooling means 80 is stopped by the UV irradiation means 50 in the vicinity of the travel standby portion 70 of the UV irradiation means and is made to stand by. It is preferable to provide an air leakage prevention wall 90 that prevents leakage to the periphery of 10. Specifically, for example, as shown in FIG. 2, the periphery of the cover 60 that forcibly circulates air may be covered with an air leakage prevention wall 90 without a gap. Then, it is preferable that the air to be forcedly circulated along the inner portion of the cover 60 does not leak to the vicinity of the standby inkjet head 10 in the vicinity thereof. The leaked air causes dust present in the periphery of the inkjet head 10 to be rolled up in the air and adhere to the nozzles 12 arranged on the lower surface of the inkjet head, or receive the wind pressure of the air, It is preferable to prevent the ink meniscus formed at the tips of the aligned nozzles 12 from being destroyed.
[0017]
In addition, as shown in FIG. 2, one or more cooling fins 92 may be extended from the inner wall of the cover 60 in the inner portion of the cover 60 where the air is forcedly circulated by the air cooling means 80. Then, air that is forced to circulate along the inner portion of the cover 60 by the air cooling means 80 may be blown onto the cooling fins 92 with a large surface area. Then, the cover 60 with the cooling fins 92 extended through the cooling fins 92 having a large surface area may be efficiently cooled by the air that is forcedly circulated along the inner portion of the cover 60 by the air cooling means 80. .
[0018]
【The invention's effect】
As described above, according to the UV irradiation mechanism of the present invention, the shutter and shutter opening / closing means for covering the window on the lower surface of the UV irradiation means for emitting the ultraviolet rays, and the air cooling means for cooling the inside of the UV irradiation mechanism are provided with the UV. The UV irradiating means can be greatly reduced in weight by eliminating or providing the irradiating means. Then, it becomes possible to quickly and accurately run the lightened UV irradiation means over the platen together with the inkjet head. Further, it is possible to reduce the cost of the printer by reducing the size of the driving means for causing the UV irradiation means to travel along the platen together with the ink jet head. In addition, it is possible to prevent the printer portion near the running standby position of the UV irradiation means from being irradiated with ultraviolet rays emitted from the window on the lower surface of the UV irradiation means and heating the printer portion to a high temperature.
[Brief description of the drawings]
FIG. 1 is a schematic structural explanatory diagram of an ink jet printer provided with a UV irradiation mechanism of the present invention.
FIG. 2 is an explanatory view of a partially broken enlarged structure of the UV irradiation mechanism of the present invention.
FIG. 3 is an explanatory diagram of a schematic structure of an ink jet printer provided with a conventional UV irradiation mechanism.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Inkjet head 20 Platen 30 Media 50 Irradiation means 52 Window 58 on the lower surface of the irradiation means UV lamp 60 Cover 70 Irradiation means travel standby point 80 Air cooling means 82 Duct 84 Intake fan 90 Air leakage prevention wall 92 Cooling fin

Claims (2)

An inkjet printer that ejects ultraviolet curable ink droplets from the inkjet head while running the inkjet head in the left-right direction above the platen, and lands the ink droplets on the surface of the media mounted on the platen in the form of dots. And
In an inkjet printer that irradiates ink droplets that have landed on the surface of the media with ultraviolet rays from a window on the lower surface of UV irradiation means that travels in the left-right direction above the platen together with the inkjet head, and dries and cures the ink droplets.
A travel standby point for stopping and waiting for the travel of the UV irradiation means is provided outside the end of the platen in the left-right direction,
When the UV irradiation means is located at the travel standby position, a cover member is provided at the standby position that is located directly below the window of the UV irradiation means and covers the window,
The cover member is formed with a passage space surrounding an inner surface opposite to the outer surface facing the window, and external air is introduced into the passage space from one end opening that opens to the opposite side of the platen in the left-right direction. Air cooling means for discharging the air to the outside from the other end side opening that opens to the opposite side of the platen in the left-right direction through the passage space;
A UV irradiation mechanism for an ink jet printer , wherein the cover member heated by the UV means positioned at the standby position is cooled by air flowing through the passage space . UV irradiation mechanism for an ink jet printer according to claim 1, characterized in that the cooling fins extending into the passage space from the inner surface of the opposite side of the window facing the outer surface of the cover member is extended.

Images