JPH04185352A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To prevent the leakage, evaporation and solidification due to drying of a residual ink by discharging the residual ink to the circulating route of an ink supply device after the supply of ink from an main ink tank to an auxiliary tank. CONSTITUTION:If an ink supply route is connected, an ink supply pump 221 is activated to continue supplying ink to a specified level of it until a sensor provided on an auxiliary ink tank 130 detects that the ink is filled to a full capacity. If the ink supply is completed, the ink supply pump 221 is deactivated to activate a valve mechanism 227 and close an area between the main ink tank 211 and the ink supply pump 221. The opening of the ink supply pump side to an atmospheric side results. Under this state, the action of the ink supply pump 221 is resumed to aspirate ink from the valve mechanism 227, an ink supply connection part 224 and an open air connection part 133. Thus the ink is discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field [0002] The present invention relates to an inkjet recording apparatus, and more particularly, to an improvement of an ink supply path system in an inkjet recording apparatus.

Jumei technique As an ink supply method for inkjet recording devices.

Various methods have been proposed in the past, but the typical ones are: 1) Connecting the main ink tank located outside the head carriage and the sub-ink tank located on the head carriage with a tube; Place the tank on the carriage,
A device that directly connects the main ink tank and the sub-ink tank; ■ A device that directly replenishes ink from the main ink tank to the sub-ink tank placed on the carriage when the carriage moves to the ink replenishment position. can give.

Both ① and ② replenish ink using the volume return force of the sub-ink tank and the capillary force of the nozzle. However, ③ is caused by fluctuations in ink pressure due to the deformation of the tube when the print head moves. This causes instability in ink ejection.

Further, there are problems such as bubbles being generated in the ink that is kept in the tube for a long period of time, and the quality of the ink changing.

■] stores enough ink for printing in the main ink tank and mounts it on the head carriage, which increases the inertia load on the hend carriage, making movement control difficult, and the large size of the carriage scanning system. This will lead to increased costs and increased costs.

■ is a system in which a sub ink tank is mounted on the head carriage, which solves the drawback of ■ by reducing the amount of ink in the sub ink tank to the minimum required amount (for example, for one page), and the main Ink can be supplied between the ink tank and sub-ink tank without going through a tube.
In other words, only when the carriage moves to the ink replenishment position, the ink supply ports on the main ink tank side and the sub ink tank side are connected to supply ink, which also solves the drawback (2) above. .

However, in case (2), there is a problem of ink leakage from the ink supply port on the sub-ink tank side and the ink supply system side. This is caused by ink remaining in the ink supply system such as the ink supply port, and especially occurs during printing after ink has been supplied or when connecting the supply port for the next supply. Cheap.

In addition, the remaining ink is particularly susceptible to evaporation, drying, and solidification, and this may accumulate in the supply path or enter the sub-ink tank, adversely affecting ink ejection.

Purpose The present invention was made in view of the above-mentioned circumstances.
In particular, this is intended to discharge the ink remaining in the ink supply path and prevent the ink from solidifying due to evaporation and drying.

In order to achieve the above-mentioned object, the present invention provides a sub-ink tank mounted on a hend carriage having a print head, a main ink tank installed other than the head carriage, and a main ink tank installed in a hend carriage having a print head; In an inkjet recording apparatus, the inkjet recording apparatus includes an ink supply means for supplying ink to an ink tank, and performs recording by scanning the head carriage and ejecting ink from the print head, the ink supply means supplying ink from the main ink tank to the main ink tank. A pump means for supplying ink to a sub-ink tank, and a switching valve disposed between the pump means and the main ink tank, and the operation of supplying ink from the main ink tank to the sub-ink tank is completed. After that, the switching valve is operated to close communication between the main ink tank and the pump means, and the pump means side is opened, and the pump means is driven to supply the ink supply system from the switching valve to the sub-ink tank. Ink remaining in the path is discharged through the opened switching valve, or a sub-ink tank mounted on a head carriage having a print head and a main ink tank installed outside the head carriage , an inkjet recording apparatus comprising: an ink supply means for supplying ink from the main ink tank to the sub-ink tank; the inkjet recording apparatus scans the head carriage and performs recording by ejecting ink from the print head; a first pump means for supplying ink from the main ink tank to the sub-ink tank; a first switching valve disposed between the first pump means and the main ink tank; , a second switching valve disposed in an ink supply path between the first switching valve and the sub-ink tank, and a second pump means connected via the second switching valve. and after the ink supply operation from the main ink tank to the sub ink tank is completed, the first
operating a switching valve to cut off ink supply from the main ink tank and opening the second switching valve to connect the second pump means to the ink supply line;
The invention is characterized in that the second pump means is driven to discharge ink remaining in the ink supply path through the second switching valve.

Hereinafter, the present invention will be explained based on examples.

FIG. 4 is a main part configuration diagram for explaining an example of an inkjet recording apparatus to which the present invention is applied. In the figure, 1 is a helad carriage, 2 is an ink supply unit (main ink tank), and 3 is a recording 101 is a carriage drive motor, 102 is a carriage drive belt, 103 is a motor pulley, 111 is a carriage guide, and 301 is a paper guide.

Reference numeral 302 denotes a paper feed roller, which, as is well known, drives the head carriage 1 reciprocatingly in the direction of arrow A using the carriage drive motor 101, and conveys the recording paper 3 in the direction of arrow B. Ink droplets are ejected from nozzles mounted on a head carriage 1 to print on recording paper 3.

In the inkjet recording apparatus described above, as described above, the ink supply unit 2 is fixed at a location other than the head carriage, and when the head carriage 1 comes to a predetermined position, the head carriage 1 moves to the ink supply unit 2. Either the ink supply unit 2 is connected to the ink supply unit 2 and ink is supplied to the head carriage 1, or the ink supply unit 2 and the helad carriage 1 are connected with a hose or the like and the ink supply unit 2 is constantly supplied to the head carriage 1. Although ink is supplied, as described above, there are adverse effects such as ink leakage from the ink supply port and solidification of residual ink in the ink supply path.

The present invention has been made to solve the above-mentioned problems, and will be described below with reference to the drawings.

FIG. 1 is a diagram illustrating the main part of an embodiment of the present invention. FIG. 1 shows a state in which the head carriage 1 has been moved to the position of an ink supply unit 2. As shown in FIG. In this configuration, the head carriage 1 is reciprocally scanned in the six directions of arrows by the active action of the Cali-Rad drive motor 101, and the print head section 120 disposed on the head carriage 1 is directed toward the recording paper according to the recording image signal. Recording is performed by ejecting ink droplets. Ink corresponding to the ink droplets ejected at this time is quickly supplied from the sub-ink tank 130. When the amount of ink in the sub-ink tank 130 falls below a specified amount (set by the remaining ink level sensor, print or paper feed counter, etc.), the main ink tank 21 of the ink cartridge 210 is removed by the operation of the ink supply unit 2.
1, ink is supplied to the sub-ink tank 130 of the head carriage 1. This ink supply is executed by moving the sub-ink tank 1 to an ink supply position where the ink supply unit 2 is located.

The ink supply unit 2 includes an ink cartridge 210 holding a main ink tank 211 and a waste liquid reservoir 212;
It is composed of an ink supply pump 221, an ink discharge pump 222, a head cap 223, an ink supply connection part 224, an atmosphere release connection part 225, a valve mechanism 226, a switching valve 227, and the like.

The main ink tank 211 is an ink cartridge 210
2, and a part of the case has an atmosphere communication hole 214 (a porous body may be provided in the main ink tank 211), or as shown in FIG. A bag 215 may be used and the ink may be stored in the ink bag 215.

The waste liquid reservoir 212 uses, for example, an ink absorber, and the ink supply pump 221 and the ink production pump 222 can be a tubing pump, a piston pump, a diaphragm pump, or the like.

Head cap 223. The ink supply connection part 224 and the atmosphere release connection part 225 are each made of soft rubber such as silicone rubber, and are pressed against the print head 120 and the sub-ink tank 130 by a spring member (not shown) or the like, and are moved as needed. They can be separated using a solenoid or the like.

(When the power is OFF, the head carriage 1 is in the ink supply position, the head cap 223, the connection cap 22
4. 225 and the like are pressed against the helad carriage 1. ) On the other hand, the head carriage 1 is composed of a carriage base 110, a print head section 120, and a sub-ink tank 130.

The carriage base 110 slides the carriage kite 111 and causes the pano I to the carriage 1 to reciprocate forward by being driven by the carriage drive motor 101.

The print head section 120 usually has a multi-configuration in which a plurality of print drive units are arranged (note that 121 indicates a nozzle).

The sub-ink tank 130 has, for example,
The structure may include an ink retaining portion 131 made of a porous material, or a film body 135 (the film body 135 is deformed to change the volume of the ink reservoir) is provided as shown in FIG. The body 135 holds ink.

These sub-ink tank holding parts 131 and 135 are moved by moving and scanning the head carriage 1.
It is possible to prevent pressure fluctuations in the ink section (supplied ink) that occur within the range of 0.

This sub-ink tank 130 is further provided with a filter 134 at an outlet portion that supplies ink to the print head portion 120 side. In addition, the ink supply port 132,
The atmosphere opening port 133 has a tapered shape so as to correspond to the connection caps 224 and 225. Note that a check valve function may be provided in the ink supply port 132 (however,
(not shown).

Next, the supply of ink in the above configuration will be explained.

When a sensor (not shown) detects that the head carriage 1 has moved to the ink supply position, the cap 22
The operation of the solenoid that moves 3, 224, 225 is O.
FF, and by the action of the spring member, the parts 121, 132, and 133 on the side of the head carriage 1 are pressed, and the ink supply path is connected (this pressing action opens the valve function installed in the part 132). )
.

When the ink supply line is connected, the ink supply pump 22
1 operates to supply a certain amount of ink in the main ink tank 211 or until a sensor provided in the sub-ink tank detects that it is full. At this time, the valve mechanism 227 is open between the main ink tank 211 and the ink supply pump 221 and closed on the atmosphere side, and the valve mechanism 226 is open. The supplied ink is held in ink holding parts 131 and 135.

Also, at this time, some of the ink overflows through the atmosphere opening port 133 and the atmosphere opening connection part 225, and the waste liquid reservoir 2
12 may be discarded.

When the ink supply ends, the operation of the ink supply pump 221 stops. Conventionally, in this state, the ink supply connection section 2
24, and connect the connection part 224 to the ink supply port 1.
32, the above-mentioned problems such as ink leakage and solidification of residual ink occurred.

Next, the valve mechanism 227 is operated to close the space between the main ink tank 211 and the ink supply pump 221, and open the ink supply pump 221 side to the atmosphere. In this state, the operation of the ink supply pump 221 is restarted, and the valve mechanism 227, the ink supply connection section 224, and the atmosphere release connection section 1 are restarted.
33 is suctioned, and the ink up to the upper surface of the ink holding portion 131 is discharged (at this time, a part of the ink may be disposed of in the waste liquid reservoir 21.2 as described above).

After that, the head cap 223 and the connection part 224.2
The solenoid 25 moves, the respective connections are released, and the cap 223 and the connecting portions 224, 225 are separated, returning to the illustrated state.

Thereby, ink remaining in the system of the ink supply means including the ink supply connection section can be discharged between the main ink ink and the ink reservoir section of the sub-ink tank.

FIG. 2 is a configuration diagram for explaining another embodiment of the present invention. In this embodiment, a discharge pump 228 is installed and the remaining ink is discharged by the pump 228. Similar to 227, the remaining ink is discharged by operating the pump 228 after switching the valve mechanism 226.

FIG. 3 is a block diagram for explaining another embodiment of the present invention, in which the supply connection is connected to the tube 13.
6, 137, and the remaining ink (in this case, the ink inside the tube 136) can be discharged in the same manner as described above.

As is clear from the above explanation, according to the present invention, after ink is supplied from the main ink tank to the sub-ink tank, the ink remaining in the ink supply means system is discharged, so that the remaining ink is It is possible to prevent leakage, evaporation of residual ink, and solidification due to drying.

[Brief explanation of the drawing]

1 to 3 are main part configuration diagrams for explaining the present invention in detail, and FIG. 4 is a main part configuration diagram for explaining an example of an inkjet recording apparatus to which the present invention is applied. be. 1-・Hend carry nozzle, 2・Main ink tank. 3... Recording paper, 110... Carriage base, 120...
・Print head section, 130-・Sub ink tank, 13
1. Ink holding unit, 210 ink cartridge,
21 domain ink tank, 212... waste liquid reservoir. Patent applicant: Ricoh Co., Ltd. - '1 (') Agent: Akito Takano (and 1 other person) 'F, i 1st Ward

Claims (1)

[Claims] 1. A sub-ink tank mounted on a head carriage having a print head, a main ink tank installed other than the head carriage, and supplying ink from the main ink tank to the sub-ink tank. In the inkjet recording apparatus, the inkjet recording apparatus includes an ink supply means, and performs recording by scanning the head carriage and ejecting ink from the print head, wherein the ink supply means supplies ink from the main ink tank to the sub-ink tie. and a switching valve disposed between the pumping means and the main ink tank, and the switching valve is operated after the operation of supplying ink from the main ink tank to the sub-ink tank is completed. to close the communication between the main ink tank and the pump means, open the pump means side, and drive the pump means to drain the ink remaining in the ink supply path in the sub-ink tank from the switching valve. An inkjet recording apparatus characterized in that discharge is performed through the opened switching valve. 2. A sub-ink tank mounted on a head carriage having a print head, a main ink tank installed outside the head carriage, and an ink supply means for supplying ink from the main ink tank to the sub-ink tank. , in an inkjet recording apparatus that performs recording by scanning the head carriage and ejecting ink from the print head, the ink supply means includes a first ink tank for supplying ink from the main ink tank to the sub-ink tie; a pump means, a first switching valve disposed between the first pump means and the main ink tank, and an ink supply path between the first switching valve and the sub-ink tank. and a second pump means connected via the second switching valve, and after the ink supply operation from the main ink tank to the sub-ink tank is completed, operating the first switching valve to cut off the supply of ink from the main ink tank and opening the second switching valve to connect the second pump means to the ink supply system; An inkjet recording apparatus characterized in that the ink remaining in the ink supply path is discharged through the second switching valve by driving the second pump means.