JP2000141704A - Waste ink recovering mechanism for ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste ink recovering mechanism for an ink jet printer capable of accurately detecting whether or not a waste ink tank is fully occupied without providing an overflow sensor or the like. SOLUTION: A printer controller 200 in a printer comprises a head cleaning counter 213 for counting the number of times of head cleaning operations and a purge counter 214 for counting the number of times of purging operations. The counted values of the counters 213, 214 are supplied to a waste ink quantity calculating circuit 215, then the accumulated value of the waste ink quantity is calculated. The calculated waste ink quantity is supplied to an overflow detecting circuit 216 and is compared with a capacity of a waste ink tank 21 so that it is detected whether or not the waste ink tank 21 is fully occupied. When it is detected that the waste ink tank 21 is fully occupied, the fact is indicated on an indicating device 219. As a result, an operator can know the time for replacing the waste ink tank 21 based on the indication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer, and more particularly to a mechanism for collecting waste ink sucked or discharged from each ink nozzle for maintenance of the ink jet head.

[0002]

2. Description of the Related Art In general, an ink-jet printer performs desired printing on a recording paper while reciprocating an ink-jet head carried on a carriage in a direction orthogonal to a conveying direction of the recording paper. The inkjet head is moved to a position outside the printing range, and maintenance is performed.

As the maintenance of the ink jet head, a head cleaning operation and a purge operation are generally known. The head cleaning operation is an operation of recovering each ink nozzle by sucking deteriorated ink or the like from each ink nozzle by an ink pump with the nozzle surface of the inkjet head capped. In addition, the purging operation is performed by wastefully ejecting ink droplets from each ink nozzle of the inkjet head,
This is an operation for recovering each ink nozzle.

The waste ink sucked or discharged from the ink nozzles by such an operation is collected in a waste ink tank via a head cap.

[0005]

When the waste ink tank is full, the collected waste ink may leak to the outside. To avoid this, it is necessary to provide an overflow sensor for detecting that the waste ink tank is full.

On the other hand, if the waste ink collected in the waste ink tank can be reused as black ink for printing, it is preferable because the ink use efficiency is increased and the ink becomes economical. In order to reuse the waste ink, a supply system for supplying the waste ink collected in the waste ink tank to the black ink tank of the ink cartridge as the ink supply source may be configured. Alternatively, a waste ink tank may be formed in a part of the ink cartridge, and a waste ink supply system may be configured such that the waste ink tank communicates with the black ink tank in the ink cartridge.

[0007] However, it is not preferable to use the highly deteriorated waste ink again for printing because it may cause nozzle clogging and the like.

SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to propose a waste ink collecting mechanism of an ink jet printer capable of detecting a full state of a waste ink tank without separately providing an overflow sensor.

Another object of the present invention is to propose a waste ink collecting mechanism of an ink jet printer capable of detecting whether the collected waste ink is suitable for reuse.

[0010]

In order to solve the above problems, the present invention provides a head cleaning operation for sucking ink from each ink nozzle and a discharge of ink droplets from each ink nozzle for maintenance of an ink jet head. In an inkjet printer performing a purge operation, a waste ink tank that collects waste ink sucked by the head cleaning operation and waste ink discharged by the purge operation, a head cleaning counter that counts the number of times of the head cleaning operation, A purge counter that counts the number of times of the purge operation; a waste ink amount calculation unit that calculates a waste ink amount based on count results of the head cleaning counter and the purge counter; and a calculation result of the waste ink calculation unit. Said waste Nkutanku is characterized by having a overflow detection means for detecting whether or not full.

In the present invention, the amount of waste ink actually discharged from the ink nozzle is estimated from the number of times of head cleaning and the number of times of purging, and based on the result, it is detected whether or not the waste ink tank is full. ing. Therefore, it is possible to detect with high accuracy whether or not the waste ink tank is full, and it is not necessary to install an overflow sensor in the waste ink tank.

Next, the present invention relates to an ink jet printer which performs a head cleaning operation for sucking ink from each ink nozzle and a purging operation for discharging ink droplets from each ink nozzle for maintenance of the ink jet head. A waste ink tank for collecting the waste ink sucked in by the purge operation and the waste ink discharged by the purging operation, and a waste ink supply unit for supplying the waste ink collected in the waste ink tank to the inkjet head as black ink for printing A head cleaning counter that counts the number of times of the head cleaning operation, a purge counter that counts the number of times of the purge operation, and the waste ink based on count results of the head cleaning counter and the purge counter. It is characterized by having a determining means for determining the supply of permissibility.

In general, when deteriorated ink is used, the number of times of head cleaning and the number of purges increase, so that the deterioration state of the ink can be accurately detected based on these times. Therefore, according to the present invention, it is possible to avoid adverse effects such as clogging of ink nozzles due to the use of waste ink which deteriorates drastically.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet printer to which the present invention is applied will be described in detail with reference to the drawings.

(Overall Configuration) FIGS. 1 and 2 are a plan configuration diagram and a cross-sectional configuration diagram showing a recording paper transport path of an ink jet printer of this embodiment. Referring to these drawings, the inkjet printer 1 has a printer main unit 2 and a paper feed unit 4 connected to the unit 2. The printer main unit 2 includes a carriage unit 8 on which a head unit 6 and an ink cartridge 7 are mounted.

The carriage unit 8 includes a pair of gears 81.
When the carriage motor 83 is driven by being connected to the timing belt 82 bridged over the a and 81b, it can reciprocate in the unit width direction along the carriage guide 84. The ink nozzle surface 61 of the head unit 6 can be reciprocated in the print area 62 by the carriage unit 8. Further, the user can move to a home position 63 outside the print area 62.

A head maintenance unit 9 is mounted on a portion of the printer body unit 2 on the side of the home position 63. The head maintenance unit 9 includes a head cap 91 and a head wiper 92 that can move up and down. When the head unit 6 is located at the home position 63, the head nozzle 92 can cap the ink nozzle surface 61. With 92, the ink nozzle surface 61 can be wiped.

The waste ink collected by the head cap 91 is collected by an ink pump 93 in a waste ink tank 21 disposed at the bottom of the printer main unit 2. Further, the waste ink wiped off by the head wiper 92 can be collected in the waste ink tank 21 disposed at the bottom of the printer main unit 2. Each operating part of the head maintenance unit 9 is driven by a motor 94.

In the main unit 2, the platen guide 22 is disposed at a position facing the ink nozzle surface 61 of the head unit 6 over the entire width of the printing range 62. Recording paper is supplied from the paper feed unit 4 to the print position defined by the platen guide 22.

The paper feed unit 4 includes a paper feed tray 41 and a paper feed roller 42 for feeding out the recording paper loaded therein one by one from above. A paper feed motor 23 (hereinafter, referred to as an LF motor) is disposed on the side of the printer main unit 2, and the LF motor 23 drives a paper feed roller 42 to rotate, thereby recording from the paper feed tray 41. Paper is sent out.

At the upstream end of the platen guide 22 in the sheet feeding direction, there is disposed a feed roller 24, which is also rotationally driven by an LF motor 23. A press roller 25 is pressed against the feed roller 24 by a spring force. I have. The recording paper fed from the paper feed tray 41 is held by the feed roller 24 and the pressing roller 25,
The sheet is conveyed toward the platen guide 22.

On the recording paper conveyed along the platen roller 22, predetermined recording is performed while the head unit mounted on the carriage unit 6 moves directly above the recording paper. Discharge rollers 26 and 27 are disposed on the downstream side of the platen guide 22 in the sheet feeding direction. These rollers are also driven to rotate by the LF motor 23, and the recorded recording paper is discharged from the discharge port 28 to the outside. Discharge.

(Ink Supply / Recovery System) Next, an ink supply / recovery system of the ink jet printer 1 will be described with reference to FIG. The ink supply source is an ink cartridge 7 removably mounted on a mounting portion formed on the carriage 8. The ink cartridge 7 has a rectangular parallelepiped shape as a whole, and the inside is divided into four sections. Each of the compartments 7K, 7Y, 7M, and 7C is an ink tank that stores black ink, yellow ink, magenta ink, and cyan ink, respectively. Each ink tank 7K,
The inks stored in 7Y, 7M, and 7C are ejected from the ink nozzles of the head unit 6 as ink droplets.
A predetermined print is formed on recording paper.

Ink droplets ejected from the ink nozzles of the head unit 6 at the home position 63 are collected by the head cap 91 of the head maintenance unit 9. The waste ink collected in the head cap 91 is
By the ink pump 93, the ink tubes 95, 96
Through the waste ink tank 21.

Here, the head cap 91 can be opened to the atmosphere via an air tube 98 and an air opening valve 99 attached to the tip thereof. When the ink pump 93 is driven to collect the waste ink collected in the head cap 91 into the waste ink tank 21, the head cap 91 is opened to the atmosphere.

In the printer 1 of this embodiment, the waste ink wiped off by the head wiper 92 mounted on the head maintenance unit 9 passes through a waste ink guide 92c made of a sponge-like ink-absorbing material attached thereto. Thus, the waste ink can be collected in a waste ink tank 21 (see FIG. 1) disposed on the bottom surface of the printer main unit 2.

As shown in FIG. 3B, the head wiper 92 includes a horizontally long wiper body plate 92a made of an elastic material such as rubber, a wiper holding plate 92b made of a rigid member holding the wiper body plate 92a, and an ink And a T-shaped waste ink guide 92c made of an absorbent synthetic resin material. The wiper body plate 92a is connected to the wiper holding plate 9
2b and the waste ink guide 92c are fastened with two screws. The wiper body plate 92a may be formed from an ink-absorbing material.

If the ink that has been wiped off from the ink nozzle surface 61 and adhered to the wiper body plate 92a of the head wiper 92 without drying remains there, there is a possibility that the surrounding area may be stained with the wiped waste ink. In particular, when an oil-based ink that does not easily dry is used as the ink, the possibility is high.

However, in this embodiment, the wiper body plate 92a
The ink wiped in step 2 is collected in the waste ink tank 21 attached to the printer main unit 2 via the waste ink guide 92c. Therefore, the ink wiped by the head wiper 92 does not adhere to the surrounding area.

(Waste Ink Tank Overflow Detection Mechanism) FIG. 5 is a schematic functional block diagram of a control system of the printer 1 of this embodiment. The printer controller 200 is mainly composed of a microcomputer, and implements various control operations using a work area in a RAM according to a control program stored in a ROM.

The printer controller 200 includes a print control circuit 210. Under the control of the control circuit 210, the head unit 6 is driven via a head driver 211, and ink droplets are ejected from each ink nozzle.
Further, the circuit 210 drives the motor 94 of the head maintenance unit 9 via the motor driver 212, and the ink pump 94 operated by this motor
Accordingly, the waste ink collected by the head cap 91 is collected in the waste ink tank 21.

Here, the printer controller 200
A head cleaning counter 213 for counting the number of head cleaning operations and a purge counter 214 for counting the number of purge operations are provided. The count values of the counters 213 and 214 are calculated by the waste ink amount calculation circuit 21.
5 is supplied. The waste ink amount calculation circuit 215 calculates an integrated value of the waste ink amount based on the input count value. The calculated waste ink amount is used as an overflow detection circuit 2
16.

The overflow detection circuit 216 compares the integrated value of the waste ink amount with a preset capacity of the waste ink tank 21 to thereby determine the waste ink tank 21.
Detects whether or not is full. Waste ink tank 21
If it is detected that is full,
The information is displayed on the display 219 via the driver 218.
The operator can know the replacement time of the waste ink tank 21 from this display.

FIG. 4 shows a modification of the ink supply / recovery system of this embodiment.
In the ink cartridge 720 shown in this figure, an ink tank 7 for yellow ink, cyan ink, magenta ink, black ink and waste ink is contained in a rectangular parallelepiped case.
2Y, 72C, 72M, 72K, 72WK are arranged in this order. The ink tank 72K for black ink and the ink tank 72WK for waste ink which are arranged adjacent to each other communicate with each other at the bottom.

That is, the waste ink tank 72W
The bottom wall 721 of K is located one step higher than the bottom wall 722 of the adjacent ink tank 72K for black ink, and between the bottom plate 721 and the bottom plate 722, the inside of the ink tank 72K for black ink is located. Ink absorber 72 disposed in
3 is extended. A core 724 for ink communication is embedded in the portion of the ink absorber 723, and an ink supply hole 725 is opened in a bottom wall 722 of the waste ink tank facing the core 724.

An ink needle insertion hole 731 is formed in the side wall of the waste ink tank 72WK. An ink needle 97 is attached to a tip of an ink tube 96 connected to a discharge side of the ink pump 93. The ink needle 97 is
When the carriage 7 returns to the home position 63, it is located at a position where it can be inserted into the waste ink tank 72WK of the ink cartridge 720 mounted thereon.

In the ink supply / recovery system having this configuration, the waste ink recovered by the head cap 91 is recovered by the ink pump 93 into the waste ink tank 72WK. The waste ink collected here is supplied to the ink tank 72K for black ink, so that it can be reused as black ink for printing.

Here, when the waste ink is reused as black ink for printing as described above, if the waste ink is severely degraded, a problem such as clogging of an ink nozzle is caused. In order to avoid such an adverse effect, the deterioration state of the waste ink may be monitored, and based on this, it may be detected whether the reuse of the waste ink is permitted.

Referring to FIG. 5, the deterioration state can be detected based on the number of times of head cleaning by the head cleaning counter 213 and the number of times of purge by the purge counter 214. That is, when the ink deteriorates, the number of times of head cleaning increases, and
The number of purges also increases. Accordingly, a deterioration detection circuit 220 indicated by a broken line in the figure is arranged, and the upper limit values of the number of times of head cleaning and the number of purge times are stored in advance. If the number of times exceeds the upper limit value, it is impossible to reuse the waste ink. , And that fact may be displayed on the display 219.

[0040]

As described above, according to the waste ink collecting mechanism of the ink jet printer of the present invention, the amount of waste ink is estimated based on the number of times of head cleaning and the number of times of purging. Is detected. Therefore, it is possible to detect with high accuracy whether or not the waste ink tank is full without installing an overflow sensor or the like separately.

In the present invention, the state of deterioration of the ink is estimated based on the number of times of head cleaning and the number of times of purging, and based on this, it is determined whether or not the waste ink can be reused for printing. Therefore, it is possible to avoid in advance the adverse effects such as clogging of the nozzles due to the reuse of the highly deteriorated waste ink.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a planar configuration of an inkjet printer to which the present invention has been applied.

FIG. 2 is a schematic configuration diagram showing a cross-sectional configuration of the inkjet printer of FIG.

FIG. 3 shows the ink supply and ink supply of the inkjet printer of FIG. 1;
It is explanatory drawing which shows a collection system.

FIG. 4 shows the ink supply and ink supply of the ink jet printer of FIG.
It is explanatory drawing which shows the modification of a collection system.

FIG. 5 is a schematic functional block diagram showing an overflow detection mechanism of a waste ink tank of the inkjet printer of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink-jet printer 2 Printer main unit 4 Paper feed unit 6 Head unit 7 Ink cartridge 8 Carriage 9 Head maintenance unit 91 Head cap 92 Head wiper 93 Ink pump 94 Motor 7Y, 7M, 7C Ink tank 7K Black ink tank 72Y, 72M, 72C Ink tank 72K Black ink tank 72WK Waste ink tank 720 Ink cartridge 200 Printer controller 210 Print control circuit 213 Head cleaning counter 214 Purge counter 215 Waste ink amount calculation circuit 216 Overflow detection circuit 219 Display 220 Deterioration detection circuit

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hideto Yoda 2-53-3 Honcho, Okaya-shi, Nagano Inside Fine Technology Co., Ltd. (72) Inventor Hideyuki Koizumi 2-3-5, Honcho, Okaya-shi, Nagano No. Fine Technology Co., Ltd. F-term (reference) 2C056 EA27 EB06 EB25 EB29 EC26 JB04 JC06 JC13 JC20 JC23 JC25

Claims (2)

[Claims] An ink jet printer for performing a head cleaning operation for sucking ink from each ink nozzle and a purging operation for discharging ink droplets from each ink nozzle for maintenance of the ink jet head, wherein the waste ink sucked by the head cleaning operation is removed. A waste ink tank for collecting ink and waste ink discharged by the purge operation; a head cleaning counter for counting the number of head cleaning operations; a purge counter for counting the number of purge operations; Waste ink amount calculating means for calculating a waste ink amount based on the count result of the purge counter; and overflow detecting whether or not the waste ink tank is full based on the calculation result of the waste ink calculating means. Waste ink collecting mechanism of an ink jet printer characterized by having a chromatography detector. 2. An ink jet printer for performing a head cleaning operation of sucking ink from each ink nozzle and a purging operation of ejecting ink droplets from each ink nozzle for maintenance of the ink jet head, comprising: A waste ink tank that collects ink and waste ink discharged by the purge operation, a waste ink supply unit that supplies the waste ink collected in the waste ink tank to the inkjet head as black ink for printing, and the head cleaning. A head cleaning counter that counts the number of operations; a purge counter that counts the number of times of the purge operation; Waste ink collecting mechanism of an ink jet printer characterized by having a that discriminating means.