JPS61241155A - Liquid jet recording device - Google Patents

Abstract

PURPOSE:To contrive long life of a recording head and to enhance a response frequency of a thermal energy generating element, by a method wherein the recording head is bonded or integrated with an ink supply container through a radiation board. CONSTITUTION:A radiation board 11 is set between a recording head and an ink supply tank which is an ink supply container and mainly composed of a subtank 9 and a subtank plate 10, and the recording head and the ink supply tank are bonded with each other through the radiation board 11. With the device constituted as the above, cooling by the liquid cooling system utilizing the ink in the ink supply tank through a radiation board 11 is made possible, enabling remarkable enhancement in cooling of the recording head, especially in efficiency of cooling a thermal energy generating element.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid jet recording apparatus that performs recording by applying thermal energy to a recording liquid to eject and fly the liquid as droplets.

[Prior Art] A liquid jet recording method, a so-called inkjet recording method, in which recording is performed by ejecting and flying a recording liquid has been known. The liquid jet recording device (inkjet recording device) used in this method generally includes a recording head for ejecting recording liquid (hereinafter referred to as ink) as ink droplets, and a recording head for discharging recording liquid (hereinafter referred to as ink) as ink droplets, and a recording head for discharging recording liquid (hereinafter referred to as ink) as ink droplets. Equipped with an ink supply system.

FIG. 3 shows an example of a recording head used in such an inkjet recording apparatus.

As shown in FIG. 3, a recording head generally includes an orifice 4 serving as an ink ejection opening, a liquid flow path 8 corresponding to each orifice, and a liquid flow path 8 for ejecting and flying the ink filling the liquid flow path as ink droplets. A thermal energy generating element 6 that supplies thermal energy (generally, a heating resistor made of various metals is used), a common liquid chamber 7 that communicates with the liquid flow path 8,
It is provided with an electrode 5 for applying a recording signal to the element 6, and an ink supply port 3 for causing ink supplied to the common liquid chamber 7 from outside the recording head to flow into the common liquid chamber 7. When constructing the recording head, a substrate 2 having excellent heat dissipation properties such as alumina, which constitutes the electrode 5 and the thermal energy generating element f6, and the ink supply port 3. Orifice 4. A recording head is obtained by joining a top plate l made of a material such as glass, ceramics, or plastic and having grooves and holes of a desired shape arranged therein to form a common liquid chamber 7, a liquid flow path 8, etc. is normal.

In such a recording head, it is sufficient that one orifice 4 for ejecting ink droplets is disposed in the recording head, and also communicates with the orifice 4 to store ink within the recording head. The ink liquid chamber also includes the common liquid chamber 7 and the liquid flow path 8.
Although it is possible to simply provide a space in the recording head that communicates with the orifice 5 without separating the functions, in order to improve recording density and recording speed, multiple orifices as shown in FIG. It is often a multi-orifice type recording head having 5 orifices.

Of course, depending on the number of orifices, etc., a desired number of thermal energy generating elements 6 are usually arranged at a desired location suitable for ejecting ink inside or outside the ink chamber of the recording head, as shown in FIG. It is.

By the way, since the recording head is generally formed as a small device, the amount of ink that can be stored in the ink chamber can only perform recording for a very short period of time.
For this reason, an inkjet recording apparatus is usually equipped with an ink supply system mainly for the purpose of storing ink and keeping the amount of ink supplied to the recording head constant.

FIG. 4 shows an example of an inkjet recording apparatus equipped with such an ink supply system.

The ink supply system of the apparatus of this example includes an ink supply section for supplying ink to the recording head 18, and when the recording head 18 is clogged with ink, the ink supply system clears the ink clog and discharges ink from the recording head. It consists of a recovery section for restoring the body to a normal state.

That is, the ink supply section includes an ink cartridge 25 that includes an ink bag 23 serving as an ink storage container in order to stably supply a fixed amount of ink free of dust and the like to the recording pad 18.
, an ink supply tube 15 for sending ink from the ink bag 23 to an ink supply tank 19 , and an ink supply tank 19 for supplying a certain amount of ink to the recording head 18 .
(The amount of ink is adjusted by a certain amount of air 2B put into the tank 19 and the waste ink tube 16 connected to the tank 18) and an ink supply tank 19.
and a filter 22 for removing dust and the like from the ink sent through the ink supply tube 14 from the ink supply tube 14. In such an ink supply section, if the only purpose is to lengthen the recording time, the ink bag 2
It is sufficient to provide an ink storage container such as No. 3 separately from the recording head 1B, but in order to stabilize the ink supply to the recording head 1B, an ink storage container such as the one described above is provided in the ink supply section separately from the ink storage container. An ink supply tank 19 is usually provided.

The recovery unit is operated when the recording head 18 is clogged with ink due to adhesion of dust or the like and the recording head 18 has an ink ejection failure. The ink inside the recording head 18 is suctioned through the waste ink tube 2B with negative pressure by the recovery pump 21, and the ink flow generated by the suction causes the ink to adhere to the recording head 18 (mainly inside and outside the orifice 4). The ink sucked by the 0-recovery pump 21, which cleans the inside of the print head 18 by removing dust etc. and restores the ink ejection of the print head 18 to a normal state, is absorbed by the pump 21.
through the waste ink tube 27 by the positive pressure caused by
The waste ink is sent to a waste ink reservoir 24 made of a porous material or the like provided inside the ink cartridge 25.

Recording by such an inkjet recording apparatus is performed, for example, as follows.

That is, for ink stored in an ink chamber of a recording head provided with an orifice 4 for ejecting small ink droplets, a thermal energy generating element is placed at a desired position inside or outside the ink chamber. 6, by applying a recording signal according to the recording pattern through the electrode 5, thermal energy is applied in a pulsed manner, and this thermal energy causes a change in the state of the ink in the ink chamber, such as liquid expansion or bubbles, and the ink This pulse-like change in state causes small ink droplets to be ejected from the orifice 4 to perform recording.

However, if the thermal energy generating element 6 is repeatedly operated at a frequency higher than a certain frequency, the surface temperature of the thermal energy generating element 6 will gradually rise, and the thermal energy generating element 6 will eventually be destroyed. In order to perform high-speed recording using the generating element 6, it is necessary to suppress the rise in the surface temperature of the thermal energy generating element 6.

Suppression of the temperature rise of the thermal energy generating element 6 is mainly achieved by heat dissipation from the substrate 2 of the recording head or cooling by ink in the ink chamber. is not necessarily sufficient, and if the temperature of the thermal energy generating element 6 rises significantly, the temperature of the ink in the ink chamber also rises, creating bubbles in the ink chamber, making ink ejection for recording unstable. This also causes problems such as having a negative impact on records. For this reason, in a conventional inkjet recording apparatus, a heat dissipation plate 11 as shown in FIG. It has been common practice to prevent the temperature rise and to suppress the temperature rise of the thermal energy generating element 6.

However, in order to obtain a sufficient heat dissipation effect, a fairly large heat sink is required, but since recording heads are generally formed as small pieces, it has been difficult to mount a large heat sink.

Therefore, with conventional inkjet recording apparatuses, it has been extremely difficult to perform high-speed recording that repeatedly performs recording at high frequencies.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned problems, and a main object of the present invention is to solve the problems in the conventional inkjet recording apparatus described above, and It is an object of the present invention to provide a new highly reliable inkjet recording device which is capable of high-speed recording without providing any particularly complicated means and by using a conventional mechanism, and which extends the life of the recording head.

[Means for Solving the Problems] The present invention that achieves the above object includes a recording head for applying thermal energy to ink and ejecting the ink as flying droplets, and supplying ink to the recording head. This is an inkjet recording apparatus characterized in that the recording head and the ink supply container are joined or integrated via a heat sink.

That is, the present invention connects or integrates the recording head and the ink supply container via a heat sink, thereby making use of the ink in the ink container, which has a high cooling capacity, to cool the recording head, especially to generate thermal energy. This type of cooling not only extends the life of the recording head but also makes it possible to increase the response frequency of the thermal energy generating element, improving reliability. This makes it possible to provide an inkjet recording device capable of high-speed recording.

Here, the ink supply container refers to a container that is provided separately from the ink chamber of the recording head and is capable of supplying ink to the ink chamber.

Specifically, for example, it is a container whose main function is to supply ink, such as the ink supply tank shown in FIG. good.

[Example] Hereinafter, an inkjet recording apparatus of the present invention will be described in detail with reference to one drawing.

1 and 2 are perspective views showing the configuration of main parts of a recording head and an ink supply container, respectively, according to an embodiment of the inkjet recording apparatus of the present invention, and the configuration other than these parts is shown in FIG. 4. It has the same configuration as the device shown in .

As shown in FIG. 1, the inkjet recording apparatus of this example has a recording head similar to that shown in FIG. A heat radiating plate 11 is disposed between the ink supply tank, which is a container, and the recording head and the ink supply tank are connected via the heat radiating plate 11. The recording head, the heat sink 118 and the ink supply tank are connected by screws 17, but it is not always necessary to connect them with the screws 17. For example, fixing means such as band tightening or adhesive may be used. can be constructed using a wide variety of conventionally known materials, and its shape is not particularly limited to those mentioned above, but can be any desired shape depending on the shape of the recording head or ink supply container, etc. It is something.

As mentioned above, in the apparatus of this example, the structure other than the recording head, the heat sink 11, and the ink supply tank is the same as that of the apparatus shown in FIG. Ink from the ink bag provided in the ink cartridge passes through the tube 15, and also passes through the ink supply tube 14 to the recording head via a filter.
Ink is supplied from the ink supply tank through the ink supply tank. Furthermore, to eliminate ink clogging, the waste ink tube 16. A recovery section similar to that shown in FIG. 4 is provided, which includes a head contact device, a recovery pump, and the like. According to the apparatus having such a configuration, unlike the conventional air cooling method using the heat sink 11, liquid cooling method using the ink in the ink supply tank via the heat sink 11 can be performed. It is possible to significantly improve the cooling efficiency of the recording head, especially the cooling efficiency of the thermal energy generating elements.

In the above example, the ink supply container connected to the heat dissipation plate was an ink supply tank of a type that mainly controls the amount of ink supplied to the recording head, similar to that shown in FIG.
The ink supply container in the present invention does not necessarily have to be an ink supply tank as in this example, and may be a single container that functions as both the ink bag and the ink supply tank in FIG. Also, the shape is not particularly limited, but if you consider joining with the heat sink,
As shown in FIG. 2, the sub-tank 9 and the sub-tank plate 1O are of a divisible format, and the material of the part that contacts the heat sink (in this case, the sub-tank plate 10) is made of a material with high thermal conductivity, such as metal. Of course, it goes without saying that it does not have to be of a divisible format.In addition, in the ink supply tank shown in Figure 2, considering the connection with the heat sink, the conventional The sub-tank plate 10, which was placed on the top of the sub-tank 9, is placed on the side of the sub-tank 9 as shown in FIG. 2 to facilitate connection with the heat sink.

Further, in the above example, the recording head, heat sink, and ink supply container are each made separately.

Although these are joined by fixing means such as screws, there are ink supply containers in which the heat sink also serves as the wall of the ink supply container (for example, a sub-tank plate), that is, an ink supply container in which the heat sink and the ink supply container are integrated. A type in which a supply container and a recording head are joined together, or a type in which a recording head in which the substrate of the recording head also serves as a heat radiating plate, that is, a type in which a heat radiating plate and a recording head are integrated, a type in which a recording head and an ink supply container are joined together, or a heat radiating plate. The substrate and the ink supply container may also serve as both the substrate of the recording head and the wall of the ink supply container, that is, the recording head and the ink supply container may be integrated via a heat sink. Both of the heat dissipation plates are made of the same material, and both the substrate and the ink supply container wall are made of the same material, or the substrate,
It is possible to construct the heat sink and the ink supply container wall as the same member.

In the present invention, as described above, it is essential to join or integrate the recording head and the ink supply container via a heat sink, but when constructing the recording head, the ink supply container, the heat sink, etc. It goes without saying that a wide variety of conventionally known means can be used, and the shapes thereof are not particularly limited to those shown in FIGS. 1 and 2.

[Effects of the Invention] As explained above, according to the present invention, the recording head and the ink supply container are joined or integrated through the heat sink, and the ink in the ink supply container, which has excellent cooling ability, is utilized. Since the recording head can be sufficiently cooled, especially the thermal energy generating element, the load on the thermal energy generating element can be reduced and the life of the recording head can be extended. , it is also possible to increase the response frequency of the thermal energy generating element, and it is possible to provide an inkjet recording device that is highly reliable and capable of high-speed recording.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the configuration of main parts near the print head of an inkjet recording apparatus according to the present invention, FIG. 2 is a perspective view showing the configuration of an ink supply tank of the inkjet recording apparatus according to the present invention, and FIG. The figure is a perspective view showing the main parts of a recording head related to a conventional inkgeniet recording device.
The figure is a schematic diagram illustrating a typical example of a conventional inkjet recording apparatus. 1-m-top plate 2-m-substrate 3--ink supply port 4-m-orifice 5--electrode 6--thermal energy generating element 7--common liquid chamber 8-m=liquid flow path 9----Subtank 10-m-Subtank plate 11--One heat sink 12---Printed circuit board 13
--- Flexible board 14.15-m- Ink supply tube 1B --- Waste ink tube 17 --- Screw 18-
--Recording head 18-m-Ink supply tank 20--
-Head adhesion device 21--Recovery pump 22--Filter 23-
--Ink bag 24-11 Waste ink reservoir 25 ---Ink cartridge 26.27-m-Waste ink tube 28-m = Air

Claims (1)

[Claims] (1) A recording head for applying thermal energy to a recording liquid to eject the liquid as flying droplets, and a recording liquid supply container for supplying the recording liquid to the recording head, A liquid jet recording device characterized in that the recording head and the recording liquid supply container are joined or integrated via a heat sink.