JP2819658B2 - Ink jet recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a compact inkjet recording apparatus with improved reliability.

[Conventional technology]

An ink jet recording apparatus in which an ink tank is installed on a carriage and moves together with a head, and an ink tank filled with an absorbing material have already been proposed.

[Problems to be solved by the invention]

However, in the conventional recording apparatus, measures against bubbles, such as measures against bubbles entering when replacing the ink tank, are not sufficient. Further, the absorbing material is liable to generate fine dust and the like, and the life of the filter is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the related art, and an object of the present invention is to provide an ink jet recording apparatus which reliably prevents air bubbles and foreign matter from entering an ink jet head.

[Means for Solving the Problems] An ink jet recording apparatus according to the present invention includes an ink tank detachably attached to a recording head and a sealing member attached to an ink supply port to the recording head, and the sealing of the ink tank. An ink jet recording apparatus comprising: a recording head having an ink supply needle inserted into a member and communicating an inside of the ink tank with a flow path to a nozzle of the recording head, wherein the ink supply needle of the recording head is provided. A first filter having an area larger than a cross section of the needle hole of the ink supply needle is mounted on the nozzle side, and a second filter is mounted on an inner end of the ink supply port of the ink tank. I do.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to examples. 1 and 2 are views showing an embodiment of a substrate of an ink jet head of a recording apparatus according to the present invention. FIG. 1 is a plan view thereof, and FIG. 2 is a cross-sectional view along AA.

A series of flow channels for the pressure chamber 2, the throttle unit 3, and the common ink chamber 4 are formed on one surface of a substrate 1 made of a plate-like material such as a polymer resin, glass or metal, and a thin plate 8 is formed thereon. They are joined to form a flow path. Each pressure chamber 2 is formed with a communication channel 5 penetrating to the opposite surface of the channel, and a nickel nozzle plate 7 having a micro nozzle hole 6 formed by electroforming is joined to the tip of the communication channel 5. A plate-shaped piezoelectric element 9 is bonded on the thin plate 8 via a common electrode film in a form corresponding to each pressure chamber. In addition, in FIG. 1, the broken line shows the place where the thin plate 8 is broken.

The ink enters through an ink supply port 10 described later, fills all the flow paths, and applies a voltage to the piezoelectric element 9 to thereby make the nozzle hole 6
More ink drops are ejected.

FIG. 3 is a cross-sectional view illustrating details of the embodiment near the ink supply port. The distal end of the connection pipe 12 is inserted into the supply port 10 provided in the substrate 1 and the thin plate 8, and the flat portion 13
To the thin plate 8. A thin first filter 11 made of nylon fiber, stainless steel fiber, or the like is arranged below the inside of the connection pipe 12, and a second connection pipe 14 is inserted so as to press the filter 11. Connection pipe 12
A rubber packing 15 is disposed between the first and second connection pipes 14 to prevent ink leakage. A supply needle 16 made of stainless steel is driven into the second connection pipe 14 from above.

As is apparent from FIG.
The filter has a larger area than the cross section of the needle hole, and reliably catches foreign substances and the like that enter when the supply needle 16 penetrates a rubber stopper 20 of an ink tank described below and is inserted into the inside of the ink tank with a large filter. This prevents an increase in flow path resistance at the time of printing, and enables smooth ink supply.

FIG. 4 is a view showing an embodiment of an ink tank used in the ink jet recording apparatus according to the present invention.

The ink tank 17 has a slightly tapered interior filled with an absorbing material 18, and holds and stores ink in the absorbing material 18. There is a second filter 19 made of nylon fiber or stainless steel fiber below the absorbent material 18 pressed against the absorbent material 18. The filter 19 is fixed by heat sealing or an adhesive. A rubber stopper 20 is pushed into and fixed to the lower part of the filter 19, and a space 21 is provided between the rubber stopper 20 and the filter 19.
Is shaped. In addition, 22 is a ventilation hole.

FIG. 5 is a diagram showing an embodiment in which the ink jet head 28 and the ink tank 17 arranged on the carriage 23 are installed. The ink jet head 28 is fixed to the carriage 23, and the ink tank 17 is a guide formed on the carriage 23.
It is inserted from above along 24. When the ink tank 17 is inserted until it touches, the supply needle 16 penetrates the rubber stopper 20, and the opening at the tip thereof projects into the space 21.

When the supply needle 16 penetrates the rubber stopper 20, it receives a greater force than above. Therefore, a projection is provided on the second connection pipe 14,
The load from above is directly received by the carriage so that the substrate 1 and the thin plate 8 are not affected.

25 is a guide shaft, and the carriage 23 is guided by the guide shaft 25 and repeats the movement in the direction perpendicular to the plane of the paper. 26 is a recording paper.

According to the prototype example, the diameter of the nozzle hole 6 is φ50 μm,
Is 30 μm, and the first filter 11 is 25 μm.
The filter mesh was set so that the above foreign substances could be blocked, and the second filter 19 could block foreign substances of 20 μm or more.

According to the embodiment of the present invention described above, a head and an ink tank are mounted on a carriage, and ink droplets are ejected downward onto recording paper to perform recording. Troubles such as initial filling of ink and intrusion of air bubbles can be implemented or recovered by the operation of the suction means outside the conventionally known recording range.

As described above, the flow path is formed almost vertically upward from the first filter to the ink tank. In the ink tank, air bubbles are difficult to advance downward due to the minute holes of the absorbing material. Further, the intrusion is further prevented by the second filter. By adhering the second filter and the absorber, it is possible to eliminate a space where air is present between the second filter and the absorber, and to smoothly flow ink from the absorber to the second filter by capillary force. When the ink tank runs out of ink, the impedance between the two electrodes in the tank (not shown) increases and an alarm is issued. When replacing the ink tank, air bubbles enter the opening of the supply needle, but when a new ink tank is installed, the air bubbles rise into the space 21 and are prevented from proceeding toward the lower supply needle. The next time the ink tank is replaced, it is discarded together with the ink tank.

The filters are installed in duplicate. Dust and fine absorbent scum are mixed in the absorbing material, and it is difficult to clean the absorbing material. However, the foreign matter is prevented from traveling toward the head by the second filter. The first filter prevents the ink cartridge from moving in the head direction even when the ink tank is removed or chips from the rubber stopper enter from the supply needle, and are not replaced until the life of the recording apparatus.

The first and second filter hole dimensions are set as described above with respect to the nozzle hole dimensions and the throttle section dimensions. That is, foreign matter that blocks the nozzle hole or the throttle portion is blocked by the first or second filter. Foreign matter that has passed through the second filter is also passed through the first filter, so that the life of the first filter without replacement is not shortened.

〔The invention's effect〕

According to the ink jet recording apparatus of the present invention, the first filter having a larger area than the cross section of the needle hole of the ink supply needle is attached to the nozzle side of the ink supply needle of the recording head, and the inner end of the ink supply port of the ink tank is mounted. By attaching the second filter to the ink tank, foreign matter and the like entering when the ink supply needle penetrates through the sealing member of the ink tank and is inserted into the ink tank can be reliably captured by the large filter, and the flow through the filter can be reliably prevented. This prevents an increase in path resistance and enables smooth ink supply.

The filter was doubled, a large number of foreign substances were captured by the replacement filter, and no burden was placed on the filter that was not replaced, and the life of the filter was prolonged despite its small area.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a substrate of an ink jet head of an ink jet recording apparatus according to the present invention, FIG. 2 is a cross-sectional view taken along a line AA in FIG. 1, and FIG. FIG. 4 shows an embodiment of an ink tank of an ink jet recording apparatus according to the present invention, and FIG. 5 shows an embodiment when an ink tank is mounted in the ink jet recording apparatus according to the present invention. The figure which showed the example. DESCRIPTION OF SYMBOLS 1 ... Head board 2 ... Pressure chamber 3 ... Throttle part 6 ... Nozzle hole 8 ... Thin plate 10 ... Supply port 11 ... First filter 12 ... Connection pipe 14 ... Second connection pipe 16 … Supply needle 17… Ink tank 18… Absorbent 19… Second filter 20… Rubber stopper 21… Space 23… Carriage 28… Inkjet head

Claims (1)

(57) [Claims] An ink tank which is detachably attached to a recording head and has a sealing member attached to an ink supply port to the recording head; an ink tank inserted into the sealing member of the ink tank and the recording medium; An ink jet recording apparatus comprising: a recording head having an ink supply needle that communicates with a flow path leading to a nozzle of a head; and a needle hole of the ink supply needle closer to the nozzle than the ink supply needle of the recording head. An ink jet recording apparatus comprising: a first filter having an area larger than a cross section; and a second filter attached to an inner end of the ink supply port of the ink tank.