JPH0911492A - Ink jet recorder - Google Patents

Abstract

PURPOSE: To provide an ink jet recorder automatically excluding residual ink from a recording head at the time of separating the head from an ink tank. CONSTITUTION: This ink jet recorder comprises a recording head 1, a detachable ink tank 2 at the head, a tank attachment or detachment detecting means 20, 21 for detecting the attachment or detachment of the tank to or from the head, and a control means for so controlling the discharge of the residual ink from the head according to the ink tank trip detection signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more specifically, a recovery mechanism for supplying ink to a recording head portion from a replaceable ink tank through an ink supply passage and for preventing ink non-ejection. And an inkjet recording apparatus having the same.

[0002]

2. Description of the Related Art Conventionally, in an ink jet recording apparatus provided with a replaceable separable ink tank, when the ink filled in the ink tank is used up, the recording density on the recording material is lowered and incomplete ink ejection is performed. As a result, the recording quality is impaired. Therefore, depending on the model, the remaining amount of ink is detected, and the user is made aware of the absence of ink by a display or the like. In such a case, however, the ink tank that has run out of ink is removed in order to replace it with a new ink tank filled with ink, and after replacement of the ink tank, recovery is performed so that new ink is supplied to the recording head section. The mechanism performs a suction operation so that a good ink ejection can be obtained in the subsequent recording operation.

[0003]

By the way, the ink tank is separated from the recording head for any reason such as the result of the detection of the remaining amount of ink, the result of recording until the ink is used up, or the condition that is not related to the remaining amount of ink. The ink remains in the recording head portion in the state where it is left as it is.

The reason for this is that the ink tank is loaded with a porous member for impregnating and holding the ink, or the bag body is filled with the ink. It is due to the increase of. That is, when the negative pressure becomes larger than the acting force of the meniscus formed in the ink ejection port of the recording head unit, the ink is not ejected from the ink ejection port, and therefore, the state in which replacement is required. Then, the ink inevitably remains on the recording head portion.

Therefore, if it takes a long time to obtain the replacement ink tank and it is left for a long time while the ink tank is removed for the above-mentioned reason, the ink in the recording head portion may be left unattended. The attachment / detachment section to / from the tank remains open, and the residual ink in the recording head section evaporates and thickens, and further solidifies and adheres to the wall surface. In particular, the above-mentioned attachment / detachment section of the recording head section has a sufficient opening area so that a stable ink supply from the ink tank side can be obtained and a filter for preventing the entry of dust is attached. It tends to accelerate the evaporation even more.

As a result, the ink supply path, the liquid path, etc. are blocked due to the ink in the above-described state, and even if the ink tank is replaced with a new ink tank, the suction pressure from the ink discharge port reaches the ink tank. The result is that the recording head is not filled with ink. For this reason, the user replaces the recording head unit with a new recording head unit if it is a replaceable recording head unit, or if the recording head unit cannot be replaced, deposits the entire device with a dealer or service department and requests repair. However, there is a problem in that it causes a large loss to the user.

It is an object of the present invention to pay attention to the above-mentioned conventional problems, and in order to solve the problems, the residual ink is automatically removed from the recording head portion immediately when the ink tank is separated from the ink tank. Another object of the present invention is to provide an inkjet recording device.

[0008]

In order to achieve such an object, the present invention provides a recording head portion having an ejection means for ejecting ink, and the recording head portion is detachably connected to the recording head portion.
An ink tank portion for supplying ink to the recording head portion, a tank attachment / detachment detection means for detecting attachment / detachment of the ink tank portion to / from the recording head portion, and an ink tank portion trip detection signal from the tank attachment / detachment detection means. And a control unit for controlling the discharge of the residual ink from the recording head unit.

[0009]

According to the present invention, when the ink tank portion is tripped from the recording head portion, the tripping is detected by the tank attachment / detachment detecting means, and the control portion remains in the recording head portion based on the tripping signal. The recovery unit or the recording head unit itself is driven so as to discharge the ink, and even if the recording head unit is left for a long time with the ink tank unit removed, residual ink may remain. It is possible to prevent the ink ejecting function from being impaired by thickening or solidifying in the recording head portion.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

1 and 2 show an embodiment of the present invention. 1 shows a state of the ink jet recording head portion according to the present invention during recording, and FIG. 2 shows a state in which the ink tank is separated from the recording head portion for ink tank replacement. In these drawings, reference numeral 1 is a recording head portion, and 2 is an ink tank portion that can be attached to and detached from the recording head portion 1 and replaced. It should be noted that the ink tank portion 2 is loaded with the porous member 3 and is kept in a state where the porous member 3 is impregnated with ink. Reference numeral 4 denotes an atmosphere communication member provided in the ink tank portion 2, 4A denotes an opening portion thereof, and 5 denotes an ink supply port on the ink tank portion 2 side.
Is sealed by a sealing member (not shown) when the ink tank portion 2 is unused.

On the other hand, the recording head unit 1 has an ink ejection unit 11
And an ink supply path 12 for supplying ink from the ink tank section 2 to the ink ejection section 11. 1
2A is an ink receiving opening that opens at the end of the ink supply path 12, 12B is a filter that is attached to the ink receiving opening 12A and that prevents dust and debris from entering the recording head unit 1, and 12C is an ink receiving opening 12A. Is a receiving flange for liquid-tightly positioning and fixing the ink tank portion 2 to the recording head portion 1 side when the ink tank portion 2 is inserted into the ink supply port 5 and attached.

Further, 13 is a liquid chamber provided in the ink ejection portion 11, 14 is a liquid passage, 15 is an ink ejection port, 16 is an electrothermal converter (hereinafter referred to as a heater), 17 is a heater 16 and a heater. 16 is a substrate (hereinafter referred to as a heater board) provided with wiring for supplying a signal for ejecting ink. Thus, as shown in FIG. 1, the ink guided from the ink tank portion 2 to the liquid passage 14 via the ink supply passage 12 and the liquid chamber 13 is formed into the ink droplet 18 from the ink ejection port 15 by selectively driving the heater 16. And is ejected, and recording with ink dots is performed on a recording material (recording sheet) (not shown).

In the case of a serial type ink jet recording apparatus, both the recording head unit 1 and the ink tank unit 2 are mounted on a carriage as will be described later, and ink is supplied at the timing of its movement during scanning of the carriage. Ejection recording is performed. Here, 20 is a tank attachment / detachment detection unit which is provided on the carriage and detects attachment / detachment of the ink tank unit 2 to / from the recording head unit 1 as shown in FIGS. Reference numeral 21 is a detection piece, and 22A and 22B are detection signal output signal lines. The detection piece 21 is formed, for example, as a spherical body that can move in the vertical direction as shown in these figures, and is elastically supported by the detection means 20 by a spring or the like (not shown). When the ink tank 2 is attached to the recording head unit 1 as shown in FIG. 1, the detection piece 21 is displaced downward due to interference with the bottom surface of the ink tank unit 2, and for example, the signal lines 22A and 22B are electrically connected. By making a physical connection, the "on" signal is output from the detection means 20 to notify a control unit (not shown) that the ink tank unit 2 is attached to the recording head unit 1. When the ink tank portion 2 is removed from the recording head portion 1 as shown in FIG.
An "off" signal is output from 0.

Reference numeral 30 is a recovery means provided outside the recording area of the recording head section 1, and 31 is shown in FIG. 2 when the recording head section 1 is moved to the position where the recovery means is provided. As described above, 32 is an ink suction pipe, and 33 is a recovery pump capable of generating a positive pressure and a negative pressure.

FIG. 3 shows an outline of the constitution of an ink jet recording apparatus to which the present invention can be applied. Here, 41 is a carriage which mounts the recording head unit 1 and the detachable ink tank unit 2 on the recording head unit 1 and scans along the guide shaft 42, and 43 is a carriage which engages with the protrusion 41A of the carriage 41, Reference numeral 41 is a guide rail, 44 is a timing belt connected to the carriage 41 for moving and scanning the carriage 41, and 45 is a carriage driving motor. Further, 46 is a platen roller capable of holding the recording sheet P at the recording position and carrying and feeding the same, and 47 is a roller driving motor. In this example, the carriage 41 is at the home position (H
When it is guided to P), the movement is detected by the HP sensor 48, the scanning of the carriage 41 is stopped at any time, and the cap member 31 of the recovery means 30 is removed during the recovery operation and the replacement of the ink tank section 2. As shown in FIG. 2, it closely contacts the ink ejection port surface of the recording head unit 1.

In FIG. 3, reference numeral 50 denotes a control unit for controlling the ink jet recording apparatus. The control unit 50 starts a recording operation by ejecting ink from the recording head unit 1 and starts a carriage driving motor 45 and a roller driving motor 47. In addition to the control of the drive of the above, the recovery means 30 controls not only a series of recovery operations but also an ink discharge operation in the recording head section 1 described later when the ink tank section 2 according to the present invention is replaced.

As described above, FIG. 4 shows the recording head unit 1 with the ink tank unit 2 separated from the recording head unit 1.
Shows the state when left unattended for some reason. Here, 19 is a schematic representation of the solidified or thickened ink in the recording head unit 1. in this way,
The ink 19 remaining in the ink ejection portion 11 and the ink supply path 12 of the recording head portion 1 adheres to the wall surface of each portion related to recording or solidifies if the recording head portion 1 is left for three days, for example. Therefore, even if a new ink tank portion 2 (not shown) is joined to the recording head portion 1 in this state and the suction recovery operation is performed by the pump 33, the above-described residual ink 19 hinders the transmission of negative pressure. Not only new ink is not replenished to the ejection portion 11, but also the ink 19 in the recording head portion 1 cannot be removed, and the recording head portion 1 must be replaced.

Therefore, in this embodiment, when the carriage 41 is moved to the home position HP and the ink tank portion 2 is detached from the recording head portion 1 mounted on the carriage 41, the cap member 31 is first moved. Is sealed on the ink ejection surface of the recording head unit 1. Then, when the ink tank portion 2 is pulled out under such a state,
An "off" signal for detecting that the ink tank portion 2 is pulled out from the tank attachment / detachment detection means 20 is a signal sensor 22A,
It is sent to the control unit 50 via 22B. Therefore, the control unit 50 drives the recovery pump 33 of the recovery unit 30 according to the tank trip signal from the tank attachment / detachment detection unit 20 to automatically suck and discharge the ink remaining in the recording head unit 1. Can be done.

The suction amount in this case depends on the negative pressure generated in the recovery pump 33, and how long it takes for the residual ink in the recording head unit 1 to be discharged.
It is stored in the memory within 0 and is obtained by driving the recovery pump 33 for that time. In this way, the ink remaining from the ink ejecting portion 11 of the recording head portion 1 to the ink supply path 12 can be replaced with new ink, and the subsequent recording can be prepared.

The discharge of ink and the replenishment of new ink have been required until now to remove the air bubbles mixed in during the ink replacement, and the ink is not particularly consumed for this example. Absent. However, according to the present embodiment, the discharge and the replenishment of ink are performed according to the attachment / detachment operation of the ink tank portion 2. According to the present embodiment, the recording head portion 1 is interlocked with the removal of the ink tank portion. The ink inside is eliminated. Thus, the recording head unit 1 from which the residual ink has been removed is kept in the state as shown in FIG. 5, so that even if the ink tank unit 2 is not connected to the recording head unit 1, it is left for a long time as shown in FIG. It is prevented that the state as shown in FIG.

Further, in the present embodiment, the ink tank portion 2 is tripped from the recording head portion 1 in the capped state, but the control portion 50 is detected by detecting that the ink tank portion 2 is tripped from the recording head portion 1. May guide the carriage 41 to the position of the recovery means 30, and the residual ink may be sucked from the recording head portion 1 by capping the carriage 41. In any case, at the time of joining a new ink tank portion, first, the recovery pump 3 is kept so as to keep the inside of the recording head portion 1 at a predetermined negative pressure.
The recording head unit 1 is filled with ink by operating the recording head unit 3.

Furthermore, in the embodiment described above, the recording head unit 1 and the ink tank unit 2 are mounted on the carriage 41 as a serial type ink jet recording apparatus, and the carriage 41 is moved to the position of the recovery means 30. Although the ink tank portion 2 is replaced here, the recording head portion 1 and the ink tank portion 2 are fixed, and the recording material moves relative to the recording head portion 1, or It goes without saying that the present invention can be widely applied to the inkjet recording apparatus in which the recovery unit 30 moves to the position of the recording head unit.

When the residual ink is discharged from the recording head unit 1, the cap member 31 of the recovery means 30 is sealed on the ink discharge surface, and the suction operation by the pump 33 for a predetermined time is performed. By replacing the time suction operation, the heater 16 of the recording head unit 1 is driven with the ink discharge port surface sealed by the cap member 31, and a sufficient number of pulses for discharging the residual ink is supplied to the heater 16. Ink may be ejected from the ink ejection port 15 according to the number of pulses, and the recovery unit 30 may accept the ink. However, the number of pulses in this case is stored in the memory of the control unit 50 in advance.

[0025]

As described above, according to the present invention, the recording head portion having the ejecting means for ejecting ink and the recording head portion detachably connected to supply the ink to the recording head portion. An ink tank portion, a tank attachment / detachment detection means for detecting attachment / detachment of the ink tank portion to / from the recording head portion, and a residual ink from the recording head portion detected by the ink tank portion trip detection signal from the tank attachment / detachment detection means. Since the control means for controlling the discharge is provided, even if the recording head portion is left for a long time with the ink tank portion being pulled out from the recording head portion, the ink tank portion Since the control unit automatically discharges the residual ink in the recording head unit in conjunction with the tripping operation, the ink thickened or solidified in the recording head unit By present, the ink discharge function of the recording head portion can be prevented from impaired. Thus, stable ink supply can be obtained after replacement of the ink tank section or reattachment to the recording head section, good recording can be maintained without wasting ink unnecessarily, and an inkjet recording apparatus that is easy for the user to use. Can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a connection state between a recording head unit and an ink tank unit according to the present invention.

FIG. 2 is a cross-sectional view schematically showing a state in which an ink tank portion is tripped from a recording head portion according to the present invention.

FIG. 3 is a perspective view showing a configuration example of a serial type ink jet recording apparatus to which the present invention is applied.

FIG. 4 is an explanatory view showing a cross section of a state where ink remains in a recording head unit left as it is with an ink tank unit being tripped.

FIG. 5 is an explanatory diagram showing, in a cross section, a state in which residual ink in the recording head unit is discharged by applying the present invention.

[Explanation of symbols]

 1 Recording Head Part 2 Ink Tank Part 3 Porous Member 4 Atmosphere Communication Member 5 Ink Supply Port 11 Ink Ejection Section 12 Ink Supply Path 12B Filter 13 Liquid Chamber 14 Liquid Path 15 Ink Ejection Port 16 Electric Heat Converter (Heater) 18 Ink Drop 19 (residual) ink 20 Tank attachment / detachment detection means 21 Detection pieces 22A, 22B Signal line 30 Recovery means 31 Cap member 33 Recovery pump 41 Carriage 45 Carriage drive motor 46 Platen roller 47 Roll drive motor 48 Home position sensor 50 Control section

Claims (7)

[Claims] 1. A recording head unit having an ejection unit for ejecting ink, an ink tank unit detachably connected to the recording head unit and supplying ink to the recording head unit, and the ink for the recording head unit. A tank attachment / detachment detection means for detecting attachment / detachment of the tank portion, and a control means for controlling to discharge the residual ink from the recording head portion by the ink tank portion trip detection signal from the tank attachment / detachment detection means are provided. An ink jet recording apparatus characterized by the above. 2. The ink jet recording apparatus according to claim 1, wherein the control unit drives the recovery unit so that the ink remaining in the recording head unit can be discharged. 3. The ink jet recording apparatus according to claim 2, wherein the recovery unit is driven for a time period during which the ink remaining in the recording head unit can be discharged. 4. The ink jet recording apparatus according to claim 1, wherein the control unit drives the recording head unit to discharge the ink remaining in the recording head unit. 5. The ink jet recording apparatus according to claim 4, wherein the control unit supplies to the recording head unit a pulse number that allows the ink remaining in the recording head unit to be discharged. 6. The recording head unit is mounted on a carriage together with the ink tank unit, and recording is performed by ejecting ink during scanning of the carriage.
6. The inkjet recording device according to any one of items 1 to 5. 7. The recording head section has an electrothermal converter that generates thermal energy that causes film boiling in the ink, as an ejecting unit for ejecting the ink. The ink jet recording apparatus according to any one of items.