JPH0535284U - Ink supply device for ink jet printer - Google Patents

Abstract

(57) [Summary] [Purpose] When the ink container is mounted on the carriage, the pressure difference between the ink inside the ink container and the outside world is eliminated before the ink supply system communicates with the ink inside the ink container. Enable ink ejection. When the ink container 3 is mounted on a carriage, the air supply hole 7a of the air supply needle 7 is made to communicate with the inside of the ink container earlier than the ink supply hole 4a of the ink supply needle 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of an ink supply device used in an inkjet printer that prints by ejecting ink from a nozzle toward paper.

[0002]

[Prior Art]

 In general, inkjet printers that perform desired printing on paper by ejecting ink supplied to the inkjet heads from their nozzles are widely used because of their quietness.

FIG. 6 is a perspective view showing a general structure of such an ink jet printer. A cylindrical platen 12 is rotatably driven inside a printer body 15. Two guide shafts 13, 13 are arranged in front of the platen 12 along the axial direction of the platen 12. A carriage 1 which can reciprocate along these guide shafts 13 is arranged. On the carriage 1, for example, a print head 2 for ejecting ink of each color such as cyan, magenta, yellow, and black, and an ink container 3 for supplying ink to the print head 2 are mounted. Further, a continuous paper 14 wound in a roll shape is provided on the rear side of the platen 12 of the printer body 15, and the paper 14 is guided to a predetermined printing position along the outer periphery of the platen 12. It is supposed to be done.

FIG. 4 shows the structure of an ink supply system and an air supply system in a conventional inkjet printer. The carriage 1 carries a print head 2 and an ink container 3, and ejects ink from nozzles 18 of the print head 2 while reciprocating along a guide shaft 13 to perform printing. An opening 3a formed at the bottom of the sealed ink container 3 is closed by a rubber stopper 8. Further, an air intake pipe 11 extending vertically is provided inside the ink container 3, and a lower opening end 11 a of the air intake pipe 11 is closed by a rubber stopper 8. An air intake port 11b is formed at the upper end of the air intake pipe 11, and a water repellent filter 9 generally made of polypropylene non-woven fabric is attached to the air intake port 11b. The ink filling amount is determined so that the air intake port 11b is located above the ink surface of the ink container 3.

FIG. 5 shows a state in which an ink container in a conventional inkjet printer is attached to a carriage. When the sealed ink container 3 is mounted on the carriage 1, the air supply needle 7 and the ink supply needle 4 pierce the rubber stopper 8 to supply the ink from the ink container 3 to the print head 2 and from the outside to the inside of the ink container 3. The respective air can be simultaneously supplied through the ink supply hole 4a of the ink supply needle 4 and the air supply hole 7a of the air supply needle 7, respectively.

Ink is supplied from the ink container 3 to the print head 2 through an ink supply needle 4 and an ink supply tube 5. Then, an amount of air corresponding to the amount of ink supplied is passed through the air supply tube 6 and the air supply needle 7, and finally through the water repellent filter 9 using a polypropylene non-woven fabric at the place where it hits the air intake port 11b. It is supplied into the ink container 3. Further, the end of the air tube 6 during printing is in a state of being released to the atmosphere.

[0007]

[Problems to be solved by the device]

 However, in the above-mentioned conventional one, when the ink container 3 is mounted on the carriage 1 as shown in FIG. 5, when the pressure inside the ink container 3 is higher than the pressure in the outside world, the nozzle of the ink head 2 is Ink droplets ooze out on the surface of 18. Even if the ink head 2 is driven to eject ink from the nozzle 18 in this state, there is a problem that the ink may not be ejected due to the influence of the ink droplets that have oozing out.

Further, when the pressure inside the ink container 3 is lower than the pressure in the outside world, air bubbles are generated in the ink due to the drawing of air from the nozzle 18, and normal ink ejection cannot be performed, resulting in normal printing. There was a problem that it could not be done. Generally, in order to prevent ink from spilling from the ink container 3 during transportation, the ink container 3 is sealed with a rubber stopper 8 before shipping. It is impossible to eliminate the difference between the ambient temperature and atmospheric pressure when the ink container 3 is sealed in the manufacturing process and the ambient temperature and atmospheric pressure when the ink container 3 is mounted on the carriage 1 for actual printing. Therefore, the above-mentioned problems frequently occurred.

The present invention overcomes the above-mentioned problems in the conventional art and eliminates the difference between the internal pressure and the external pressure in the ink container 3 in the first step of mounting the ink container 3 on the carriage 1. It is an object of the present invention to provide an ink supply device for an inkjet printer that enables normal and reliable printing by supplying the ink inside the ink container 3 to the ink supply system in the second step thereafter. ..

[0010]

[Means for Solving the Problems]

 An ink supply device of an ink jet printer of the present invention for achieving the above-mentioned object is an ink supply device which is connected to an ink supply unit of an ink container and has a communication port for supplying the ink in the ink container to a print head. A system and an air supply system connected to the air supply part of the ink container and having a communication port for supplying air into the ink container, and the ink supply system when the ink container is mounted on the carriage. And an ink supply unit for an ink jet printer in which each communication port of the air supply system is connected to the ink supply unit and the air supply unit of the ink container, respectively. And the respective communication ports provided in both of the supply systems are connected to the air supply system and the air inside the ink container when the ink container is mounted on the carriage. It has a feature that the communication is arranged with a positional relationship such as is done with the ink supply system and the ink inside the container in click after the communication has been made.

[0011]

[Action]

 According to the ink supply device of the inkjet printer of the present invention having the above-described configuration, when the ink container is mounted on the carriage, the communication between the air supply system and the air part inside the ink container is established by the ink supply system and the ink. By doing this prior to communicating with the ink inside the container, it is possible to eliminate the difference between the pressure inside the ink container and the external pressure before the ink supply system communicates with the ink inside the ink container. Also, it is possible to prevent air bubbles from being generated inside the ink due to ink droplets adhering to the nozzle hole surface of the print head when the ink container is attached, and drawing of air into the nozzle. Therefore, stable printing can be performed immediately after mounting the ink container on the carriage.

[0012]

【Example】

 The present invention will be described below with reference to the embodiments shown in the drawings. It should be noted that the same or corresponding configurations as those of the above-described conventional one are denoted by the same reference numerals in the drawings, and the description thereof will be omitted.

FIG. 1 shows a first embodiment of the present invention. In this embodiment, the rubber plug 8 for sealing the ink container 3 has a recess 16 larger than the outer shape of the air supply needle 7 at the portion in contact with the lower opening end 11a of the air intake pipe 11. The depth of the recess 16 is such that when the air supply hole 7a of the air supply needle 7 communicates with the air inside the ink container 3, the ink supply hole 4a of the ink supply needle 4 is still buried in the rubber stopper 8. The positional relationship between the two supply systems 4a and 7a and the inner surface of the rubber stopper 8 is set so that the ink is submerged and does not communicate with the ink inside the ink container 3.

When the ink container 3 is mounted on the carriage 1 in the first embodiment, the air supply needle 7 and the ink supply needle 4 pierce the rubber stopper 8 below the ink container 3 in the first step. At this time, the air supply hole 7a of the air supply needle 7 communicates with the air inside the lower opening end 11a of the air intake pipe 11. The air supply needle 7 communicates with the air supply tube 6, and the other end of the air supply tube 6 is open to the atmosphere, so that the inside of the ink container 3 immediately has the same pressure as the outside world. .. In this state, the ink supply hole 4a of the ink supply needle 4 is not yet in communication with the ink inside the ink container 3, so that the ink cannot be led out to the inkjet head 2.

When the ink container 3 is further pushed into the carriage 1 by the continuous operation from the first step, the ink supply hole 4a of the ink supply needle 4 communicates with the ink inside the ink container 3 and the ink is fed to the inkjet head 2. It becomes possible to supply the ink. At this time, in the nozzle 18 of the ink jet head 2, since the pressure inside the ink container 3 is equal to the pressure in the outside, ink droplets overflow from the nozzle 18 to the outside of the head 2, or air is injected into the nozzle 18 from the outside. It is possible to prevent a problem that air is mixed into the ink by being drawn in and bubbles are generated.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made if necessary. For example, there is a method of changing the shape of the rubber stopper 8 that seals the ink container 3, the ink supply needle 4, or the length and shape of the air supply needle 7.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, a convex portion 8a is provided at the position where the ink supply needle 4 of the rubber stopper 8 is pierced and on the surface in contact with the ink. It is included. When the ink container 3 is mounted on the carriage 1, the air supply hole 7a of the air supply needle 7 communicates with the air intake tube 11 inside the ink container 3. At this time, the ink supply hole 4a of the ink supply needle 4 is buried in the convex portion 8a of the rubber stopper 8, and since the ink supply hole 4a has not reached the ink inside the ink container 3, the ink is supplied to the ink supply tube. It isn't enough to lead to Bu 5. When the ink container 3 is further pushed into the carriage 1 from this state, the ink supply hole 4a communicates with the ink inside the ink container 3 and the ink can be led out to the ink supply tube 5. The same effect as that of the embodiment can be obtained. Further, as a modification of the second embodiment, the convex portion 8a of the rubber plug 8 can have the same effect even if the inside is hollow.

FIG. 3 shows a third embodiment of the present invention. In this embodiment, the length of the air supply needle 7 is made longer than the length of the ink supply needle 4, and the ink container 3 is set to the carriage 1. , The air supply hole 7a of the air supply needle 7 pierces the rubber plug 8 before the ink supply hole 4a of the ink supply needle 4 and communicates with the air inside the air intake tube 11 inside the ink container 3, Since the ink supply hole 4a of the ink supply needle 4 is still buried in the rubber stopper 8, the ink cannot be led to the ink supply tube. When the ink container 3 is further pushed into the carriage 1 from this state, the ink supply hole 4a of the ink supply needle 4 communicates with the ink inside the ink container 3 and the ink can be led out to the ink supply tube 5. The same effects as those of the first embodiment can be obtained.

[0019]

[Effect of the device]

 As described above, according to the present invention, when the ink container is mounted on the carriage, the air supply system and the air inside the ink container are communicated before the ink supply system and the ink inside the ink container are communicated with each other. Since the pressure difference between the inside of the ink container and the outside world can be removed by communicating with the inside of the ink container, the ink overflows due to the pressure difference between the inside and outside world of the ink container when the ink container is attached, and the air is drawn into the inside of the ink due to the air being drawn into the outside world. Problems such as air bubbles can be prevented. Therefore, it is possible to maintain normal ejection of ink immediately after mounting the ink container, and it is possible to perform normal printing without trouble.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of an essential part showing a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of an essential part showing a second embodiment of the present invention.

FIG. 3 is a partial cross-sectional view of an essential part showing a third embodiment of the present invention.

FIG. 4 is a cross-sectional view of essential parts showing a state before the conventional ink container is mounted on the carriage.

FIG. 5 is a cross-sectional view of essential parts showing a state in which a conventional ink container is mounted on a carriage.

FIG. 6 is a perspective view showing a general inkjet printer.

[Explanation of symbols]

 1 Carriage 2 Print Head 3 Ink Container 4 Ink Supply Needle 4a Ink Supply Hole 5 Ink Supply Tube 6 Air Supply Tube 7 Air Supply Needle 7a Air Supply Hole 8 Rubber Plug 11 Air Intake Tube 11a Lower Open End

Claims (1)

[Scope of utility model registration request] 1. A print head and a communication port for supplying ink in the ink container to the print head, the print head being connected to the ink supply unit of the ink container, on a carriage on which the ink container is detachably mounted. An ink supply system having the same and an air supply system connected to the air supply unit of the ink container and having a communication port for supplying air into the ink container are provided, and the ink when the ink container is mounted on the carriage. An ink supply device for an ink jet printer, wherein each communication port of a supply system and an air supply system is connected to an ink supply unit and an air supply unit of the ink container, respectively. The communication ports provided in both the supply systems communicate the air supply system with the air inside the ink container when the ink container is mounted on the carriage. The ink supply device for an ink jet printer, wherein the ink supply system and the ink inside the ink container are arranged in such a positional relationship that they are communicated with each other.