JPH1178049A - Ink jet recording device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent leakage of ink due to inclination of a box. A valve chamber (33) communicating with an outlet (31) of an ink supply needle (30) and an ink supply tube (16), and a valve body (36) moving forward and backward to the outlet (31) and moving forward and backward by a shaft (23) connected to the outlet (31) and a paper feed motor. Is provided in the cartridge holder 12, and the flow path between the recording head and the ink cartridge is opened and closed by utilizing the rotation of the paper feed motor accompanying the initialization processing and the printing end processing.

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 having a recording head which moves in the width direction of a recording sheet, and ejecting ink droplets onto the recording sheet in accordance with print data to form an image. The present invention relates to an apparatus, and more particularly, to a mechanism for supplying ink from an ink cartridge to a recording head.

[0002]

2. Description of the Related Art An ink jet recording apparatus for recording print data by discharging ink pressurized in a pressure chamber from a nozzle as ink droplets onto a recording sheet is known as an ink viscosity caused by evaporation of an ink solvent from a nozzle opening. This causes a problem that printing failure occurs due to rise of ink, solidification of ink, adhesion of dust to nozzle openings, and mixing of air bubbles into a pressure generating chamber or the like. For this reason, an ink jet recording apparatus is a capping device for sealing a nozzle opening during non-printing to prevent ink from evaporating, and for applying a negative pressure to the nozzle opening to forcibly discharge ink from the nozzle opening. And a pump unit for supplying a negative pressure thereto.

On the other hand, in order to improve print quality in color printing, four colors of magenta, cyan, yellow, and black are used.
2. Description of the Related Art An ink jet recording apparatus using two kinds of colors, that is, two kinds of light and shade, has been proposed.

As described above, since the ink cartridges using multicolor inks require ink cartridges for at least eight colors, the total weight of the carriage becomes large in a recording apparatus in which the ink tank is mounted on the carriage. Therefore, not only is a large output required for the carriage drive motor, but also there are problems such as a large recoil of the carriage upon carriage return.

In order to solve such a problem, a system in which an ink cartridge is housed in a box and ink is supplied to a recording head via an ink supply tube is desired.
In order to accommodate the ink cartridges for the colors while maintaining the weight balance of the entire recording apparatus, the ink cartridges must be arranged on both sides.

For this reason, when the recording apparatus is tilted to change the installation location while the ink cartridge is loaded, the head pressure of the ink cartridge disposed on one side of the box against the recording head increases. Thus, an ink cartridge having no negative pressure applying member such as a porous body has a problem that ink leaks from a nozzle opening of a recording head. For this reason, the maker usually removes all the ink cartridges when moving a short distance such as changing the installation location, and uses an ink filling mechanism for the long distance transportation with the ink supply tube. It is recommended to remove the ink remaining on the recording head.
In the former case, some ink stagnant in the flow path only needs to slightly flow out of the cap from the recording head in the capped state, and in the latter case, it prevents overflow from the cap. can do.

However, since such leakage or discharge of ink involves entry of the atmosphere into the flow path, a negative pressure is applied to the recording head after the ink cartridge is mounted to fill the recording head with the ink of the ink cartridge. Operation is required, and there is a problem that it takes time to start printing and consumes ink.

[0008]

In order to avoid such a problem, a valve mechanism which can be driven electromagnetically is connected in the middle of the ink supply tube so that the ink flow path between the ink cartridge and the recording head in a non-printing state. Although shutoff is performed, there is a problem that the valve mechanism is complicated and large in size, and furthermore, the number of connection points of the ink supply tube is increased to cause air to enter the ink supply flow path. I have.

The present invention has been made in view of such a problem, and has as its object to reduce the number of connecting portions of an ink tube without requiring a large space for installing a valve mechanism. An object of the present invention is to provide an ink jet recording apparatus capable of preventing the invasion of the atmosphere.

[0010]

According to the present invention, in order to solve such a problem, the present invention is mounted on a carriage,
Ink jet recording comprising: a recording head reciprocatingly driven in the width direction of recording paper; and a cartridge holder connected to an ink supply tube via an ink supply needle and containing an ink cartridge for supplying ink to the recording head. In the apparatus, a valve comprising a valve chamber communicating with the outlet of the ink supply needle and the ink supply tube, and a valve body that moves forward and backward by a shaft connected to a paper feed motor are provided in the cartridge holder, and an initialization process is performed. In addition, the valve body is moved by the rotation of the paper feed motor in the end processing to open and close the ink cartridge, the recording head, and the flow path.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows an embodiment of the present invention. A carriage 1 is connected to a motor 3 by a timing belt 2 and is guided by guide members 4 and 4 so as to move in parallel with a platen 5. It is configured. On the surface of the carriage 1 facing the recording paper, a first recording head 7 and a second recording head 8 are mounted side by side in the moving direction of the carriage 1, and on the upper surface, a sub-tank unit 9 having a damper function, 10 are mounted.

On both sides of the frame 11, cartridge accommodating portions 12 for accommodating a plurality of ink cartridges are provided, and via ink supply tubes 16, 16, 16,. One is connected to the sub tank unit 9,0.

As shown in FIG. 2, the valve units 14 and 14 have a drive mechanism 24 that receives power from a shaft 23 connected to a drive shaft of a paper feed roller 21 connected to a paper feed motor 20 via a train 22 as shown in FIG. And a camshaft 25 as its output shaft
Thus, the valve is opened and closed via an operating rod. Reference numerals 26 and 27 in the drawing indicate an idle roller and a paper discharge roller of the paper feed mechanism.

FIG. 3 shows one embodiment of the valve unit 14 with respect to one ink cartridge housed in the cartridge holder 12. When the cartridge is loaded in the cartridge housing section 12, the ink supply of the ink cartridge is performed. At a position facing the septum of the mouth, an ink supply needle 30 inserted therethrough is fixed. The other end of the ink supply needle 30 is extended outside the holder 12 to form an ink outlet 31, and is connected to the ink supply tube 16 via a valve 32.

The valve 32 has a valve chamber 33 formed of a spherical recess formed so as to have the outlet 31 of the ink supply needle 30 as a center point, and an ink supply tube connection port 34 communicating with the side of the valve chamber 33. A valve body 36 made of an elastic material such as rubber, which is hermetically attached to the base 35 so that the valve chamber side is convex, and
Is urged to come into contact with the outlet 31 and the camshaft 2
5 and an operating rod 38 connected to the valve body 36 so as to form a gap with the outlet 31.

One end of a valve lever 40 supported by a rotating shaft 39 formed on the base 35 is connected to the tip of the operating rod 38.

The above-described drive mechanism 24 is provided with a camshaft 25 having a length reaching the plurality of valve levers 40 to a toothless gear 41 having a toothless region 41a so as to secure an inoperative region.
Is mounted, and is configured to selectively engage with one of the first and second planetary gears 43 and 43 ′ meshing with the sun gear 42 provided on the shaft 23.

In this embodiment, when the recording apparatus is turned on and an initialization operation is performed, the paper feed motor 20 is turned on.
Rotates to discharge the recording paper remaining on the platen 5. The rotation of the paper feed motor 20 (in the direction indicated by the arrow B in FIG. 4) is transmitted to the sun gear 42 via the wheel train 22 and the first planetary gear 43 comes into contact with the toothless gear 41 to rotate it. Let it.

As a result, the cam shaft 25 rotates, and as shown in FIG. 4, the tip of the valve lever 40 is moved away from the outlet 31 against the urging force of the spring 37, and the ink supply needle 30 is moved. And the ink supply tube 16 are communicated.

When the sun gear 42 rotates by a predetermined amount, the first planetary gear 43 faces the 41 toothless region 41a of the toothless gear, and hence, regardless of the rotation of the paper feed motor 20 in the paper feed direction thereafter. The valve 32 maintains the open state. Further, the second planetary gear 43 'does not engage with the toothless gear 41 by a slight rotation of the paper feed motor 20 in the opposite direction, so that the valve-opening state is also maintained.

In this state, when the ink is sucked for maintenance of the recording heads 7 and 8 which is an initialization operation, the ink of the ink cartridge flows into the sub tanks 9 and 10 via the ink supply tube 16 and the ink is supplied. Supplies ink to the recording heads 7 and 8.

Since the valve 32 is provided with a valve body 36 having a convex shape on the valve chamber 33 side, the dead space of the valve chamber 33 is made small.
Without decreasing the flow velocity, and maintaining the high
Pass through. In addition, the flow path communicating from the valve chamber 33 to the outside is:
Since the air bubbles are formed in the direction opposite to the direction of gravity, the accumulated bubbles move upward. As a result, the bubbles in the valve chamber 33 in which the bubbles are relatively easy to accumulate are easily discharged from the recording heads 7 and 8 to the outside along with the ink flow.

When the printing operation is completed after the initialization operation is completed, the recording heads 7 and 8 receive the supply of ink from the ink cartridge, discharge ink droplets in accordance with the print data, and form dots on the recording medium. .

When a predetermined time elapses after the printing operation is completed, the carriage 1 moves to the capping device 27 and seals the nozzle opening with the capping device 27 in order to prevent the ink in the nozzle opening from drying. In this state, the paper feed motor 20 is rotated slightly backward to engage the carriage 1 with a locking piece (not shown) driven by the paper feed roller 21 to lock the carriage 1.

The reverse rotation of the paper feed motor 20 (in the direction indicated by arrow A in FIG. 3)
2 is also reversed, and the second planetary gear 43 ′ is
, And the missing gear 41 is rotated by the second planetary gear 43 ′ by the further reverse rotation of the paper feed motor 20 to rotate the cam shaft 25, and the valve 37 is actuated by the spring 37 via the valve lever 40. The body 36 elastically contacts the outlet 31 in the state shown in FIG. 3, and shuts off the ink supply needle 30 and the ink supply tube 16.

In this state, even if there is a difference in elevation between the right and left during the conveyance of the recording apparatus to change the installation location of the recording apparatus, the head pressure of the ink cartridge is shut off by the valve 32. No excessive head pressure is applied, and ink does not leak from the recording heads 7 and 8.

Although the operating rod 38 is operated via the lever 40 in the above-described embodiment, the same applies when the operating rod 38 is operated by the cam shaft 25 without the intervention of the valve lever 40. It works.

Further, in the above-described embodiment, an example in which the ink cartridges are dispersed on both sides of the box and the ink cartridges are accommodated has been described. It is clear that the same effect is obtained even if the method is applied.

[0029]

As described above, according to the present invention, the valve comprising the valve chamber communicating with the outlet of the ink supply needle and the ink supply tube, and the valve element which is advanced and retracted by the shaft connected to the paper feed motor. Provided in the cartridge holder, it is possible to open and close the flow path between the recording head and the ink cartridge by using the rotation of the paper feed motor accompanying the initialization processing and the printing end processing, and a large space for installing the valve mechanism. It is possible to prevent the intrusion of the atmosphere by reducing the number of connection points of the ink tube without requiring ink, and also to cut off the communication between the ink cartridge and the recording head to prevent ink leakage due to the inclination of the box when not operating. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a top view showing one embodiment of an ink jet recording apparatus of the present invention.

FIG. 2 is a diagram showing a power transmission system in the device.

FIG. 3 is a view showing a state in which a structure near an ink supply needle of a cartridge holder of the same device is closed.

FIG. 4 is a view showing a valve opening state of a cartridge holder of the same device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carriage 7, 8 Recording head 9, 10 Buffer tank unit 12 Cartridge holder 16 Ink supply tube 20 Paper feed motor 23 Valve drive mechanism drive shaft 24 Valve drive mechanism 25 Cam shaft 30 Ink supply needle 31 Outlet 32 Valve 33 Valve Chamber 36 Valve element 40 Valve lever 41 Missing gear 42 Sun gear 43, 43 'Missing gear

Claims (5)

[Claims] 1. A recording head mounted on a carriage and driven reciprocally in the width direction of recording paper, and an ink cartridge connected to an ink supply tube via an ink supply needle and supplying ink to the recording head. In an ink jet recording apparatus having a cartridge holder for accommodating, a valve comprising a valve chamber communicating with an outlet of the ink supply needle and the ink supply tube, and a valve body which moves forward and backward by a shaft connected to a paper feed motor. And an ink jet recording apparatus provided with the cartridge holder. 2. The valve body is driven by a planetary gear mechanism connected to a paper feed mechanism, a toothless gear driven by the planetary gear mechanism, and a cam integrally attached to the toothless gear. The ink jet recording apparatus according to claim 1. 3. The ink jet recording apparatus according to claim 2, wherein the cam is configured as a shaft, and drives the valve elements provided in a plurality of ink cartridges. 4. The ink jet recording apparatus according to claim 1, wherein said valve chamber is directly connected to the other end of said ink supply needle. 5. The ink jet recording apparatus according to claim 1, wherein the valve element is urged by a spring so as to always close the outlet.