JPH0525671B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid jet recording device, and more particularly, to a liquid jet recording device in which a plurality of energy generators serving as droplet discharge means are provided for one droplet discharge port. and a liquid jet recording head used therein.

Non-impact recording methods, especially the so-called liquid jet recording methods, have various advantages such as almost no noise during recording, high-speed recording, and the ability to record on plain paper without the need for special fixing treatment. Because of this, research and development have been actively conducted recently.

On the other hand, the recording head used in this recording method has an ejection opening (ejection orifice) for ejecting a colored liquid called ink and causing it to fly as droplets, and an inlet for the liquid to flow into. A recording head is used. There are various types of recording heads depending on the method of ejecting liquid from the ejection ports.

In this process, thermal energy is applied to the liquid to vaporize the liquid and generate bubbles, and the increase in internal pressure associated with the generation of the bubbles forms flying droplets to perform recording. There is a recording method.

Further, there is a liquid jet recording method in which recording is performed by applying mechanical energy such as a piezo to the liquid so that the liquid is ejected from an ejection port to form flying droplets.

These recording methods are based on the fact that it is relatively easy to produce a high-density multi-orifice recording head through precision microfabrication compared to other methods, and A4
This method is considered to be one of the promising methods because it is possible to manufacture a full-line multi-orifice recording head larger than this size, and the head itself can be significantly miniaturized.

However, although this recording method has such excellent points, it suffers from poor durability and reliability due to low yield in the process of arranging the energy generating elements and destruction of the energy generating elements due to pressure changes, etc. It is difficult to actually put it on the production line. These points become more serious problems especially in the case of a full-line multi-nozzle orifice recording head of A4 size or larger. Therefore, it is eagerly desired to develop a liquid jet recording apparatus having a configuration that solves these problems.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a highly reliable liquid jet recording device that is durable, has excellent droplet ejection stability, and has excellent long-term continuous recording performance. shall be. Another object of the present invention is to provide a liquid jet recording device in which recording defects due to defects in the energy generating body are reduced, and which can be manufactured with a simple manufacturing process and a high yield.

A first aspect of the present invention provides a recording head that is applied to the above-mentioned apparatus, and includes an ejection port for ejecting liquid droplets, and an ejection port that generates energy for ejecting liquid from the ejection port to form flying droplets. In a liquid jet recording head having an energy generating body, the energy generating body is, in addition to an initial driving energy generating body that is initially driven, driving of which is switched depending on a malfunction of the initial driving energy generating body. The present invention is characterized in that it has a preliminary energy generator which is driven by the discharge port in correspondence with the discharge port.

A second aspect of the present invention achieves the above object, and includes an ejection port for ejecting droplets, and an energy source corresponding to the ejection port to eject the liquid from the ejection port to form flying droplets. A liquid jet recording head is used that has an initial drive energy generator that is driven at the beginning of generating the liquid and a backup energy generator that is driven when the initial drive energy generator is malfunctioning. The liquid jet recording apparatus is characterized in that it includes means for switching the drive for the ejection port to the backup energy generator in response to malfunction of the initial drive energy generator.

Hereinafter, the present invention will be explained using figures. FIG. 1 is a schematic perspective partial view for explaining an embodiment of the present invention. In the figure, 11a and 11b are energy generators, 12 is a substrate, and 13 is an ejection opening from which droplets are ejected, and the imaginary positions are shown in the figure. 14 is the center line of the discharge port, and 15 is a dividing wall for dividing each discharge portion.

This embodiment shows an example in which the energy generators 11a and 11b are arranged point-symmetrically with respect to the center line 14. As the substrate 12, a substrate suitable for a head of a liquid jet recording apparatus, such as glass, ceramics, plastic, or metal, was used, and energy generating bodies 11a and 11b made of electrothermal converters were arranged. In this embodiment, the dividing wall 15 is made of photosensitive resin. Furthermore, a discharge port plate (not shown) having discharge ports 13 was laminated on the dividing wall 15 . As a matter of course, at least one of the electric wires (not shown) connected to one energy generator is independently connected to each of the energy generators 11a and 11b.

A portion surrounded by the ejection port plate, the dividing wall 15, and the substrate 12 is supplied with liquid for ejecting droplets from the ejection port 13. Now, if electricity is applied to either the energy generator 11a or 11b, in the case of this embodiment, the liquid is vaporized and bubbles are generated, and the resulting pressure causes droplets to be ejected from the ejection port 13. Droplets were ejected in the same way regardless of which of the energy generators 11a and 11b was energized.

FIG. 2 is an explanatory diagram for explaining how to drive the liquid jet recording apparatus of the present invention. In FIG. 2, 21 is an energy generator, 22 is an arithmetic circuit, and 2
3 is a driver, and 24 is an energy generator selection circuit. 25 is a discharged droplet, and 26 is a recording member.

At the beginning of the operation of the liquid jet recording apparatus, one of the energy generators 21 corresponding to one ejection port is selected by the energy generator selection circuit 24. However,
In the manufacturing process of a liquid jet recording device, for example, in the process of installing the energy generator, if a defect occurs in the energy generator, or if the energy generator is damaged or damaged due to operation of the energy generator for recording. If a defect occurs, such information is transmitted to the energy generator selection circuit 24.
When the energy generator selection circuit 24 receives the information, it stops energizing the energy generator 21 that has been used or has been energized, and switches to another energy generator 21 that corresponds to the same discharge port. Switch the energization.

The liquid jet recording apparatus of the present invention is driven in this manner.

Returning to FIG. 1, the above drive will be explained as follows.

For example, a signal is first input to the energy generator 11a, but if the energy generator 11a is defective or becomes defective during use, the center line 14 between the energy generator 11a and the discharge port 13 The signal input is switched to the energy generators 11b arranged symmetrically with respect to the center. Since the energy generating body 11b is located at a rotationally symmetrical position with the energy generating body 11a, the droplets discharged from the discharge port 3 are discharged under exactly the same discharge conditions as the droplets discharged by the energy generating body 11a. .

Therefore, even when switching the energy generators, the switching could be done extremely smoothly.

In this embodiment, an electrothermal transducer is used as the energy generator, but it is also possible to use an electromechanical transducer such as a piezo element or other means normally used in liquid jet recording devices.

The energy generators were arranged point-symmetrically with respect to the center of the discharge port, but if the same energy generators (with the same size and other conditions) were used, the environment around the energy generator (for example, liquid The way the flow of
If the positional relationship between the dividing wall and the discharge port plate does not change, the position is not point symmetrical, but is a straight line that passes through the center line of the discharge port and is perpendicular to or parallel to the liquid supply direction. They may be arranged at rotationally symmetrical positions. Furthermore, although it is possible to have a similar configuration by changing the capacity and size of the energy generator or the means for ejecting droplets, it is possible to make the size, ejecting direction, and flying direction of the ejected droplets the same. Therefore, the ability of the energy generator to eject droplets is not very desirable because it is difficult to set the placement location.

Furthermore, although this embodiment shows an example in which droplets are ejected in a direction perpendicular to the direction of the supplied liquid, droplets are ejected in the same direction as the direction of the supplied liquid. It goes without saying that the present invention can be applied to various things.

Furthermore, although the present invention has been described with reference to two energy generators, it is also possible to have two or more energy generators, for example three or four. However, in order to avoid changing the ejection conditions of any energy generator or the conditions of the ejected droplets, and to avoid complicating and difficult manufacturing processes such as wiring, it is necessary to generate too much energy. It is not desirable to correspond the body to one outlet. Further, it is similarly not preferable to use a plurality of energy generators to eject droplets. The number of energy generators should be determined in consideration of the manufacturing process, manufacturing cost, installation conditions for the energy generators, and the like.

According to the present invention, even if one of the energy generators is damaged, the energy generator is switched to another energy generator installed with the same discharge conditions as the previous one, resulting in highly durable liquid jetting. A recording device is provided. Furthermore, a good yield can be obtained in manufacturing a liquid jet recording device.
Furthermore, there is provided a highly reliable liquid jet recording device that has excellent droplet ejection stability and long-term continuous recording performance.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective partial view for explaining an embodiment of the present invention, and FIG. 2 is an explanatory diagram for explaining a driving method. 11a, 11b, 21... energy generator,
12... Substrate, 13... Discharge port, 14... Discharge port center line, 15... Division wall, 22... Arithmetic circuit, 2
3...Driver, 24...Energy generator selection circuit, 25...Droplet, 26...Recorded member.

Claims (1)

[Scope of Claims] 1. A liquid jet recording head having an ejection port for ejecting liquid droplets, and an energy generator that generates energy for ejecting liquid from the ejection port to form flying droplets, comprising: The generator includes, in addition to the initial drive energy generator that is driven first, a backup energy generator that is driven by switching the drive depending on a malfunction of the initial drive energy generator at the discharge port. A liquid jet recording head characterized in that it has a corresponding one. 2. The liquid jet recording head according to claim 1, wherein the liquid jet recording head is provided with a plurality of the ejection ports and the energy generating body in a full line. 3. Ejection characteristics of droplets ejected from the ejection port by driving the initial driving energy generator;
Liquid ejection according to claim 1 or 2, characterized in that the ejection characteristics of the droplets ejected from the ejection port due to the drive of the preliminary energy generator are substantially the same. Record head. 4. The preliminary energy generator and the initial drive energy generator are arranged in point-symmetrical, line-symmetrical, or rotationally symmetrical positions with respect to the center line of the discharge port. The liquid jet recording head according to any one of items 1 to 3. 5. The liquid jet recording head according to any one of claims 1 to 4, wherein the preliminary energy generator and the initial drive energy generator are electrothermal converters. 6 an ejection port for ejecting droplets; an initial drive energy generator that is driven at the beginning to generate energy to eject liquid from the ejection port and form flying droplets in correspondence with the ejection port; A liquid jet recording apparatus that performs recording using a liquid jet recording head having a backup energy generator that is driven when the driving energy generator is malfunctioning, the initial driving energy being A liquid jet recording apparatus characterized by comprising means for switching the drive for the ejection port to the backup energy generator in response to malfunction of the generator. 7. The liquid jet recording apparatus according to claim 6, wherein the liquid jet recording head includes a plurality of the discharge ports and the droplet discharge means arranged in a full line. 8. Ejection characteristics of droplets ejected from the ejection port by driving the initial drive energy generator;
Liquid ejection according to claim 6 or 7, characterized in that the ejection characteristics of the droplets ejected from the ejection port due to the drive of the preliminary energy generator are substantially the same. Recording device. 9. Claim 9, characterized in that the preliminary energy generator and the initial drive energy generator are arranged point-symmetrically, line-symmetrically, or rotationally symmetrically with respect to the center line of the discharge port. The liquid jet recording device according to any one of items 6 to 8. 10. The liquid jet recording apparatus according to any one of claims 6 to 9, wherein the preliminary energy generator and the initial drive energy generator are electrical converters.