JPH10309806A - Ink feed unit and ink-jet printer with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink feed unit which is compact and enables high-speed printing at low running costs without the need for exchanging ink tanks frequently, and an ink-jet printer having the same. SOLUTION: The ink feed unit has an ink tank 1 mounted on a carriage for supplying ink to a printing head, and an ink replenishment container 22 fixedly set at a predetermined standby position to feed a replenishment ink to the ink tank 1. When the carriage stops at a position where the carriage aligns with the ink replenishment container 22 to replenish ink, an ink feed opening 23 formed at a lower part of the ink replenishment container 22 and an ink receipt opening 4 set at an upper part of the ink tank 1 are connected with each other, thereby constituting a passage. As a result, ink can be replenished to the ink tank 1 from the ink replenishment container 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an ink supply unit incorporated in a printer of various image forming apparatuses and an ink jet printer having the same.

[0002]

2. Description of the Related Art In recent years, on-demand type inkjet printers have been widely used as output printers for home and office computers because of their quietness in recording and the ability to perform color printing at low cost. In particular, recently, there is an increasing demand for higher speed.

FIG. 8 is an exploded perspective view showing a configuration example of an ink tank used in a conventional ink jet printer.

In FIG. 8, reference numeral 47 denotes an ink absorber;
8 is an ink holding container that stores and holds the ink absorber 47;
49 is a print head mounted on the outer surface of the ink holding container 48, 50 is a filter provided in the ink absorber 47, 51
Is an air communication port, and 52 is an ink supply port that matches the filter 50 and the air communication port 51.

[0005] The ink absorber 47 is made of a continuous ether-based urethane foam in which polyether polyol, toluene diisocyanate, silicon, and tertiary amine are mixed and foamed, and after the foaming, the film is removed by an explosion method. The ink is absorbed and held by the capillary force. The ink absorber 47 is compressed and processed by an arbitrary volume, and is inserted and held in the ink holding container 48 with almost no gap.

In the ink holding container 48, a print head 49 is mounted on a carriage that reciprocates on a recording medium during printing so as to be parallel to the recording medium during printing. The print head 49 selectively ejects ink to a recording medium in accordance with a print signal, and forms a picture or a character composed of a matrix of dots on the recording medium. Ink ejection methods include a method in which bubbles of a desired size are formed in the ink by heating a heater disposed in the ink, and the ink droplets are ejected to a recording medium by the pressure, and a method in which the volume of the piezoelectric element is varied. A method of ejecting ink by a change is well known.

The filter 50 is located immediately above the print head 49 and is caulked to the ink supply port 52 by ultrasonic welding or the like. Ink absorber 47 near filter 50
Since the ink is locally compressed, the capillary force becomes stronger than other parts, and the retained ink tends to gather near the filter 50. Further, the filter 50 prevents clogging of the ink ejection ports of the print head 49 due to dust, bubbles, etc. when the ink held in the ink absorber 47 is supplied to the print head 49.

Further, the atmosphere communication port 51 communicates the inside of the ink holding container 48 with the atmosphere, thereby preventing a sudden pressure change due to a decrease in ink volume.

However, in such an ink tank, since the print head 49 and the ink holding container 48 are integrated, if the ink in the ink holding container 48 is consumed, the print head 49 can still be used. Nevertheless, the print head 49 and the new ink tank must be replaced. Therefore, the print head 49, which is a relatively expensive member in the ink tank, is wasted.

On the other hand, as shown in FIG. 9, in order to make the print head 49 and the ink holding container 48 separable, a head separation type which can be separated into an ink tank 53 and a print head 54 is provided. Ink tanks have already been proposed.

In the illustrated example, the ink tank 53 has an ink holding container 48 containing an ink absorber 47 and an air communication port 5 for introducing air into the ink holding container 48.
1, a projection 55 formed on the side surface of the ink holding container 48 for engaging with the print head unit 54, and an ink supply hole 56 for supplying ink to the ink supply port 52 of the print head unit 54. ing.

The print head unit 54 includes a print head 49 bonded and fixed to a print head holding member 57, and an ink supply port 5 for supplying ink to the print head 49.
2, and a filter 50 disposed immediately above the ink supply port 52 and caulked by ultrasonic welding or the like.

An ink tank 53 is provided in the print head 54.
In order to engage and hold the ink tank 53 when the is inserted, the print head holding member 57 at a position corresponding to the projection 55 of the ink tank 53 is provided with an engagement hole 58. When the ink tank unit 53 and the print head unit 54 are integrally engaged, the ink supply port 52 and the filter 50 compress and press the ink absorber 47 through the ink supply hole 56 of the ink tank unit 53.

The print head unit 54 and the ink tank unit 53 are mounted on the carriage by mounting the print head unit 54 on the carriage and then integrating the ink tank unit 53 with the print head unit 54 or by mounting the print head unit 54 on the carriage. What is necessary is just to mount it on the carriage integrally with the ink tank unit 53 in advance.

With such a head-separated ink tank, the ink tank unit 53 and the print head unit 54 can be separately separated, so that when the ink in the ink absorber 47 is consumed. However, only the ink tank unit 53 needs to be replaced, and the print head unit 54 is more economical without wasting it.

[0016]

However, in the head-separated ink tank having the structure shown in FIG. 9, the ink tank containing the ink for achieving a predetermined printing life can be obtained by a single ink tank replacement. Since the carriage is integrally mounted on the carriage, the entire weight of the ink mounted on the printer is added to the carriage, so that the carriage becomes heavy. As a result, it is very difficult to increase the printing speed.

Further, it is necessary to increase the size of the carriage,
The whole device becomes large and expensive. For this reason,
It is difficult to mount a large amount of ink on the printer, and the ink tank must be replaced frequently, which increases the user's labor and running cost.

The problem to be solved in the present invention is to provide an ink supply unit which is small in size, capable of high-speed printing, does not require frequent ink tank replacement, and has a low running cost, and can be effectively used for an ink jet printer. Is to do so.

[0019]

An ink supply unit according to the present invention comprises an ink tank mounted on a carriage for supplying ink to a print head, and a predetermined ink supply for supplying refill ink to the ink tank. An ink replenishing container fixedly arranged at a standby position, the ink replenishing container being provided at a lower portion of the ink replenishing container when the carriage stops at a position aligned with the ink replenishing container when refilling the ink tank. The ink jet printer is characterized in that it has a flow path configuration in which the port and the ink receiving port provided in the upper part of the ink tank are connected and connected.

The ink jet printer according to the present invention is provided with an ink supply unit having the above configuration.

According to the present invention, it is possible to realize an ink jet printer that is small in size, capable of high-speed printing, does not require frequent ink tank replacement, and has a low running cost.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to a first aspect of the present invention is directed to an ink tank mounted on a carriage for supplying ink to a print head, and a predetermined standby for supplying replenishing ink to the ink tank. An ink supply unit provided at a lower portion of the ink replenishing container when the carriage stops at a position matching the ink replenishing container when refilling the ink tank. And the ink receiving port provided in the upper part of the ink tank are connected and connected, and the ink tank mounted on the carriage is reduced in size and weight, and the capacity of the ink mounted on the printer is increased. Has the effect of enabling

According to a second aspect of the present invention, a valve member is provided in each of the internal flow paths of the ink receiving port and the ink supply port. The valve member is capable of closing the internal flow path, and has an effect of preventing fluctuation of ink components due to evaporation of volatile components in the ink, drying, and entry of dust and the like into the ink tank.

According to a third aspect of the present invention, a pressurizing means for pressurizing the ink sealed in the ink replenishing container is provided inside the ink replenishing container. Has the effect that ink can be quickly supplied and replenished.

According to a fourth aspect of the present invention, the valve members provided in the ink receiving port and the ink supply port are elastically urged in a direction from the inside to the outside of the ink tank and the ink replenishing container, respectively, to close the valve. When the ink tank and the ink replenishing container are connected to each other, the ink receiving port and the ink supply port are opened so that the ink can be replenished.

According to a fifth aspect of the invention, each of the valve members of the ink receiving port and the ink supply port is provided with a packing for sealing between the valve member and the valve seat when the valve is closed.
The sealing pressure of the packing has the effect of increasing the airtightness of the ink receiving port and the ink supply port.

According to the sixth aspect of the present invention, at least one of the valve member of the ink supply port and the valve member of the ink receiving port is provided with a projection protruding to the outside, and the ink tank moves to the ink replenishing position and the ink tank moves to the ink replenishing position. When aligned with the replenishing container, the protrusions allow the valve members to be driven to the open position by the interference between the valve members and to communicate the ink supply port and the ink receiving port. When the interference between the valve members due to the projections is released, the valve members are each capable of returning to the valve-closed position, and the ink replenishment and stopping are performed in conjunction with the connection of the ink tank and the ink replenishing container and the release thereof. It has the effect of making it possible.

According to a seventh aspect of the present invention, there is provided an ink supply apparatus in which the urging force of the elastic means attached to the valve member of the ink supply port is made larger than the urging force of the elastic means attached to the valve member of the ink receiving port. When the supply port and the ink receiving port are set to be in communication with each other, the valve member on the ink receiving port side is driven to the valve opening position before the ink supply port side, and the ink supply port and the receiving port communicate with each other. When released from the state, the valve member on the ink supply port side is driven to the valve closing position prior to the ink receiving port side. This has the effect of preventing the ink from scattering and preventing the ink from remaining on the valve member at the end of the ink replenishment operation.

According to an eighth aspect of the present invention, the valve member is made of a water-repellent material, and has an effect of preventing ink from remaining on the valve member at the end of the ink replenishment operation.

According to a ninth aspect of the present invention, there is provided an ink jet printer provided with an ink supply unit having the above-described configurations. The ink jet printer can reduce the size and weight of the carriage and can mount a large amount of ink on the printer. Having.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an ink tank of an ink supply unit according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view illustrating a configuration in which a head block in which an ink tank is loaded is mounted on a carriage.

In FIG. 1, 1 is an ink tank, 2 is a head block, and 3 is a carriage. Ink tank 1
Is made of a plastic such as polycarbonate, and is removably loaded in the head block 2.
In a color ink jet printer, four color inks of black, yellow, magenta, and cyan are used. Therefore, a total of four ink tanks 1 for the respective color inks are loaded in the head block 2 side by side.

Reference numeral 4 denotes an ink receiving port for receiving ink from an ink replenishing container described later. Inside the ink receiving port 4, a valve formed by a combination with an ink tank valve member 6 and a packing 5 for improving airtightness is provided. Is stored. The ink tank valve member 6 is made of a plastic material. If a highly water-repellent material such as a fluororesin or a polyacetal resin is used, the ink can be supplied more smoothly, and the surface of the ink tank valve member 6 can be supplied when the ink replenishment is completed. This is preferable because clogging of the valve and a decrease in airtightness due to the adhesion and remaining of the ink can be prevented.
An O-ring made of an elastic member such as EPDM can be used as the packing 5, and is fixed to a lower portion of the ink receiving port 4.

Normally, the ink tank valve member 6 is pressed from the back by the pressing spring 7 and is in close contact with the packing 5 so that the ink receiving port 4 is closed.
Only when ink is replenished from the ink replenishing container, the ink tank valve member 6 is pushed down and the ink receiving port 4 is opened. The ink tank valve member 6 is provided below the portion of the ink tank valve member 6 that is in close contact with the packing 5.
Is provided with a notch 9 for introducing the ink into the ink chamber 8 when the ink is replenished by being pushed down, and to improve the flow of the ink and to prevent the ink from remaining at the end of the ink replenishment. Is inclined.

The ink chamber 8 is provided with a partition plate 10 and the lower part thereof is partitioned into two spaces communicating with each other. In the lower part of the space opposite to the ink receiving port 4, ink is supplied to the head block 2. An opening 11 for supplying is provided. The outer peripheral portion of the opening 11 is in close contact with an O-ring 12 formed of an elastic material such as EPDM formed on the head block 2. In the space, an ink absorber 13 for absorbing and holding ink by capillary force is inserted and held between the outer wall of the ink tank chamber 8 and the partition plate 10 with almost no gap.

Here, as the ink absorber 13, various known sponge materials and the like can be used. Polyether polyol, toluene diisocyanate, silicon, tertiary amine and the like are mixed and foamed, and the film is removed by an explosion method. A communication-type ether-based urethane foam or the like to which is applied is suitably used. Immediately after the ink is replenished, the ink absorber 13 is filled with the ink 14, and the space below the ink receiving port 4 is further filled with the ink 1.
4 is stored. Reference numeral 15 denotes a minute communication port for communicating the air in the ink chamber 8 to the outside.

The head block 2 is made of plastic such as polycarbonate, and is detachably attached to the carriage 3 by a cover 17 held on the carriage 3 so as to be openable and closable at a hinge portion 16, and ejects ink to the lower surface. Print head 18 is provided. The print head 18 is bonded and held on a heat radiating plate 19 made of metal such as aluminum in order to prevent a temperature rise of an IC (not shown) provided near the print head 18 for driving itself. Things.

Since four color inks are used in the color ink jet printer as described above, print heads 18 for each color are formed in the head block 2 side by side. An ink introduction path 20 for supplying ink from the opening 11 of the ink tank 1 to the print head 18 is provided at the back of each print head 18. A filter 21 for preventing dust and air bubbles from entering the print head 18 from the ink 14 inside is fixed by ultrasonic welding or the like.

FIG. 3 is a perspective view of the ink supply unit of the ink supply unit according to the embodiment of the present invention. FIG. 4 is a side sectional view of the ink supply unit of the ink supply unit according to the embodiment of the present invention. FIG. 3 is a front sectional view of an ink supply container of the ink supply unit according to the embodiment of the present invention.

In these figures, reference numeral 22 denotes a main body of an ink replenishing container made of plastic such as polycarbonate;
Reference numeral denotes an ink supply port provided at the bottom of the ink refill container main body 22 for supplying refill ink to the ink receiving port 4 of the ink tank 1.

Reference numeral 25 denotes an ink pack in which a replenishing ink 24 is sealed. The ink pack 25 is made of a film obtained by laminating a multi-layered aluminum film or the like having a high air barrier property on a plastic film such as polypropylene. Things. In addition, the ink pack 25
Is sandwiched between a cylindrical outer cap member 26 having an ink supply port 23 formed therein and an inner cap member 27 coaxially joined thereto with the periphery of a circular opening provided at a lower portion. Have been. The outer cap member 26 and the inner cap member 27 are made of plastic such as polypropylene.

Inside the ink supply port 23, a valve having the same configuration as the ink tank 1 is provided by an ink replenishing container valve member 28, a packing 29 and a pressing spring 30 so as to face downward. The materials and configurations of the ink supply container valve member 28 and the packing 29 are the same as those provided in the ink tank 1. And ink tank 1
As in the case of the above, the ink replenishment container valve member 2
8 is pressed from the back by a pressing spring 30 and closely adheres to a packing 29 fixed inside the external cap member 26, and the ink supply port 23 is sealed. Only when ink is refilled into the ink tank 1, the ink replenishment container valve member 28 is pushed up to open the ink supply port 23, and the replenishment ink 24 in the ink pack 25 is discharged. The spring pressure of the holding spring 7 of the ink tank 1 is
It is assumed that the pressure is lower than the spring pressure of the holding spring 30.

Packing 29 of ink replenishment container valve member 28
A cut-out portion 31 for discharging the ink 24 when the ink replenishing container valve member 28 is pushed up and replenished with ink, similarly to the ink tank valve member 6 of the ink tank 1, is provided above the close contact portion of the ink tank 1. Is provided. In addition, the periphery is inclined to improve the flow of the ink and to prevent the ink from remaining when the ink is replenished.
As in the case of the ink tank 1, if a material having high water repellency such as a fluororesin or a polyacetal resin is used for the ink replenishing container valve member 28, the ink supply can be made smoother and the ink replenishment can be performed when the ink replenishment ends. This is preferable because ink can be prevented from adhering and remaining on the surface of the container valve member 28.

Reference numeral 32 denotes a pressing plate made of plastic or a thin metal plate. The pressing plate 32 is provided with a spring 3 disposed between one side of the ink tank main body.
The side of the ink pack 25 is pressed by the urging force of No. 3. By pressing the replenishing ink 24 in the ink pack 25 by the pressing plate 32 in this manner, the replenishment of the ink can be performed quickly and at high speed. In addition,
As described above, since four color inks are used in the color ink jet printer, usually four ink replenishing containers 22 are mounted on the printer.

FIG. 6 is a perspective view showing a configuration example of a color ink jet printer using the ink supply unit of the ink tank 1 and the ink replenishing container 22.

In FIG. 6, reference numeral 34 denotes a printer frame, and 35 denotes a recording medium such as paper.
Is fed from the rear to the front of the platen 37 using the pickup roller 36, and is fixed on the platen 37 by the feed roller 38. A carriage 3 on which a head block 2 including an ink tank 1 is mounted is supported by a carriage guide 39 and a carriage shaft 40 arranged in parallel to a printing surface, and a timing belt 43 connected to a pulley 41 and a drive pulley 42.
, And reciprocates in the left-right direction with respect to the feeding direction of the recording medium 35. The drive of the timing belt 43 is transmitted to the drive motor 44 via the drive pulley 42, and the rotation of the drive is controlled in accordance with the forward / reverse rotation of the drive motor 44. The image recording signal is sent to the print head 18 at a time when the carriage 3 moves, and the recording medium 35
Recording is performed by ejecting ink droplets at the upper predetermined position.

The ink supply container 22 has an ink supply port 23.
Is detachably held by the holder 45 in a state of being exposed at a lower portion on the near side. The holder 45 is rotatably held in the up-down direction by the frame 34 and the side plate 46, and can be moved up and down about the holding portion as a fulcrum by a cam gear (neither is shown) that rotates in conjunction with a stepping motor. Usually, the holder 45 holds the carriage 3
Is held at a predetermined position such that the ink replenishing container 22 and the ink tank 1 do not come into contact with or interfere with each other even when the ink cartridge 1 is located below the holder 45.

The ink replenishing operation in the above configuration will be described in detail with reference to FIG. 7 showing the state of the ink receiving port 4 and the ink supply port 23.

At the time when the remaining amount of ink in the ink tank 1 becomes low and replenishment is required, first, the carriage 3 moves to a predetermined position below the holder 45. At this time, the ink receiving port 4 of the ink tank 1 is located immediately below the ink supply port 23 of the ink replenishing container 22, but the ink receiving port 4 of the ink tank 1 and the ink supply port 23 of the ink replenishing container 22 are not shown in FIG. (A), and the ink tank valve member 6 and the ink replenishment container valve member 28 are not in contact with each other.

Subsequently, the holder 45 is rotated down by the rotation of the cam gear, and the tip of the ink tank valve member 6 and the tip of the ink replenishment container valve member 28 come into contact with each other. When the holder 45 is further lowered, the spring pressure of the holding spring 7 of the ink tank valve member 6 is higher than the spring pressure of the holding spring 30 of the ink replenishing container valve member 28.
Is lowered in the ink receiving port 4, and the ink receiving port 4 is opened as shown in FIG. 7B.

When the ink tank valve member 6 descends to the lowest point, the ink replenishment container valve member 28 subsequently rises in the ink supply port 23, and the ink supply port is opened as shown in FIG. The pressurized refill ink 24 in the pack 25 flows from the ink supply port 23 to the ink receiving port 4. At this time, the replenishing ink 24 flows from the outer peripheral portion of the ink replenishing container valve member 28 to the outer peripheral portion of the ink tank valve member 6 and quickly flows in, so that it does not scatter around.

When the time required to replenish a predetermined amount of ink elapses, the holder 45 is rotated upward by the rotation of the cam gear, and the ink replenishing container valve member 28 is lowered in the ink supply port 23. As shown in FIG. 7B, the ink supply port 23 is closed again. At this time, the ink receiving port 4 remains open due to the difference in the spring pressure described above, and the ink on the ink replenishing container valve member 28 and the ink tank valve member 6 after the ink supply port 23 is closed enters the ink chamber 8. Inflow. When the holder 45 further rises, the ink tank valve member 6 subsequently moves to the ink receiving port 4.
7A, the ink receiving port 4 is closed again as shown in FIG. 7A, and the ink replenishing operation is completed.

Here, if the ink tank valve member 6 and the ink replenishment container valve member 28 are made of a highly water-repellent material such as a fluororesin or a polyacetal resin as described above, the ink can be supplied more smoothly. When ink replenishment is completed, clogging of the valve and reduction in airtightness due to residual ink adhered to the surfaces of the ink tank valve member 6 and the ink replenishment container valve member 28 can be prevented.

With the above configuration, it is possible to achieve both a reduction in the size and weight of the carriage and an increase in the capacity of the ink mounted on the printer.

[0055]

According to the present invention, it is possible to realize an ink jet printer which is compact and capable of high-speed printing, does not require frequent ink tank replacement, and has a low running cost.

According to the second aspect of the present invention, fluctuations of the ink components due to evaporation of volatile components in the ink, drying, and entry of dust and the like into the ink tank are prevented, and good operation of the print head is ensured. Printing becomes possible.

According to the third aspect of the present invention, the ink can be supplied from the ink replenishing container to the ink tank quickly and replenished in a short time, so that the replenishing time can be shortened and the operation rate can be improved.

According to the fourth aspect of the present invention, when the ink tank and the ink replenishing container are connected, the ink receiving port and the ink supply port are opened and the ink can be replenished. Can be performed integrally, and the number of constituent members can be reduced.

According to the fifth aspect of the present invention, since the airtightness of the ink receiving port and the ink supply port is enhanced by the seal pressure of the packing, leakage of ink and deterioration of quality are prevented.

According to the sixth aspect of the present invention, the ink can be replenished and stopped in conjunction with the connection and disconnection of the ink tank and the ink replenishing container, so that the number of components and the replenishing time can be reduced.

According to the present invention, the ink is prevented from being scattered at both the start and end of the ink replenishment operation, and the ink is prevented from remaining on the valve member at the end of the ink replenishment operation. Reliable operation of the member is maintained.

According to the eighth aspect of the present invention, since the ink is prevented from remaining on the valve member at the end of the ink replenishment operation, more reliable operation of the valve member is ensured.

[Brief description of the drawings]

FIG. 1 is a perspective view of an ink tank of an ink supply unit according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a configuration in which a head block in which an ink tank is loaded is mounted on a carriage.

FIG. 3 is a perspective view of an ink supply container of the ink supply unit according to the embodiment of the present invention.

FIG. 4 is a side sectional view of an ink supply container of the ink supply unit according to the embodiment of the present invention.

FIG. 5 is a front sectional view of an ink supply container of the ink supply unit according to the embodiment of the present invention.

FIG. 6 is a perspective view showing a configuration example of a color inkjet printer using an ink supply unit of an ink tank and an ink replenishing container.

FIG. 7 is a diagram showing a state of an ink receiving port and an ink supply port.

FIG. 8 is an exploded perspective view showing a configuration example of an ink tank used in a conventional inkjet printer.

FIG. 9 is a cross-sectional view illustrating a configuration of a conventional head-separated ink tank.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink tank 2 Head block 3 Carriage 4 Ink receiving port 5 Packing 6 Ink tank valve member 7 Pressing spring 8 Ink chamber 9 Notch 10 Partition plate 11 Opening 12 O-ring 13 Ink absorber 14 Ink 15 Communication opening 16 Hinge REFERENCE SIGNS LIST 17 cover 18 print head 19 radiator plate 20 ink introduction path 21 filter 22 ink refill container main body 23 ink supply port 24 refill ink 25 ink pack 26 external cap member 27 internal cap member 28 ink refill container valve member 29 packing 30 pressing spring 31 Notch 32 Pressing plate 33 Spring 34 Frame 35 Recording medium 36 Pickup roller 37 Platen 38 Feed roller 39 Carriage guide 40 Carriage shaft 41 Pulley 42 Drive Lee 43 Timing belt 44 Drive motor 45 Holder 46 Side plate 47 Ink absorber 48 Ink holding container 49 Print head 50 Filter 51 Atmospheric communication port 52 Ink supply port 53 Ink tank 54 Print head 55 Projection 56 Ink supply hole 57 Print head holding Member 58 Engagement hole

Claims (9)

[Claims] An ink tank mounted on a carriage for supplying ink to a print head, and an ink replenishing container fixedly arranged at a predetermined standby position for supplying refill ink to the ink tank. An ink supply unit provided at a lower portion of the ink replenishing container and an ink receiving port provided at an upper portion of the ink tank when the carriage stops at a position aligned with the ink replenishing container when refilling the ink tank. An ink supply unit, characterized in that the ink supply unit has a flow path configuration in which the flow path and the flow path are connected to each other. And a valve member provided in each of the internal passages of the ink receiving port and the ink supply port. When the ink receiving port and the ink supply port are not in communication with each other, each valve member connects the internal flow path. The ink supply unit according to claim 1, wherein the ink supply unit can be closed. 3. The ink supply unit according to claim 1, further comprising a pressurizing means for pressurizing the ink sealed in the ink supply container inside the ink supply container. 4. A valve member provided in an ink receiving port and an ink supply port is elastically urged in a direction from an inner side to an outer side of an ink tank and an ink replenishing container, respectively, so that it can be restrained at a valve closing position. Claim 2 or Claim 3
The ink supply unit as described in the above. 5. A valve according to claim 2, wherein each valve member of the ink receiving port and the ink supply port is provided with a packing for sealing between the valve member and the valve seat when the valve is closed. The ink supply unit as described in the above. 6. A method according to claim 1, wherein at least one of the valve member of the ink supply port and the valve member of the ink receiving port is provided with a projection protruding outside, and when the ink tank is moved to the ink replenishing position and aligned with the ink replenishing container, The valve members can be driven to the open position by the interference between the valve members due to the projections, and the ink supply port and the ink receiving port are communicated with each other. Is canceled,
The ink supply unit according to any one of claims 2 to 5, wherein each of the valve members is capable of returning to a valve closing position. 7. The ink supply port and the ink receiving port may be configured such that the urging force of the elastic means attached to the valve member of the ink supply port is larger than the urging force of the elastic means attached to the valve member of the ink receiving port. When the communication state is set, when the valve member on the ink receiving port side is driven to the valve opening position prior to the ink supply port side, and when the ink supply port and the receiving port are released from the communication state, 7. The ink supply unit according to claim 2, wherein the valve member on the ink supply port side is driven to the valve closing position prior to the ink reception port side. 8. The ink supply unit according to claim 2, wherein the valve member is made of a water-repellent material. 9. An ink jet printer comprising the ink supply unit according to claim 1.