AU2002301858B2 - Ink Tank, Ink Jet Head Cartridge, and Ink Jet Recording Apparatus - Google Patents

Description

S&F Ref: 483394D2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant: Actual Inventor(s): Address for Service: Invention Title: Canon Kabushiki Kaisha 30-2 Shimomaruko 3-chome Ohta-ku Tokyo 146 Japan Osamu Morita Hiroshi Koshikawa Kenji Kitabatake Spruson Ferguson St Martins Tower,Level 31 Market Street Sydney NSW 2000 (CCN 3710000177) Ink Tank, Ink Jet Head Cartridge, and Ink Jet Recording Apparatus The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845c L I 1 INK TANK, INK JET HEAD CARTRIDGE, AND INK JET RECORDING APPARATUS BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an ink tank and a tank holder that detachably holds the ink tank, as well as an ink jet head cartridge provided with the tank holder and an ink jet head that performs recording by discharging ink. The invention also relates to an ink jet recording head provided with the ink jet head cartridge.

Related Background Art For the ink jet recording apparatus that records by discharging ink, it is known to arrange the structure so that the recording head that discharges ink and the ink tank that supplies ink to the recording head are formed integrally as an ink jet head cartridge which is separable as one unit from the recording apparatus main body, and at the same time, the ink tank is separable from the recording head on the recording apparatus or the head and the ink tank are made separable from each other in a state of being separated from the recording apparatus. For a structure of the kind, it is required to make the recording head and the ink tank easily separable, but ink is supplied to the head reliably when the ink tank is installed on the 2 recording head.

Figs. 1A and 18 are views which illustrate one example of an ink jet head cartridge having the recording head and ink tank arranged separably. Fig.

IA is a perspective view which shows the tank holder.

Fig. IB is a cross-sectional view thereof. As shown in Fig. 1B, the upper face of the box type tank holder 103 is open in order to hold the ink tank which will be described later. On one side portion of the lower face of the tank holder 103, the ink jet head 102 is arranged. Also, the upper side face of the tank holder 103 is inclined externally as the guide. Then, upper end portion 43 thereof is formed to abut upon the third pawl 133 of the ink tank which will be described later.

For the ink jet head 102, the silicon substrate 201 is supported by the base plate 205. On the silicon substrate 201, heaters that serve as electrothermal transducing members are formed to generate thermal energy which is utilized for discharging ink.

Also, for the ink jet head 102, the joint 204 is formed to be connected with the ink supply port of the ink tank when the ink tank is installed on the tank holder 103. For the joint 204, the ink flow paths 206 are formed toward the silicon substrate 201.

Figs. 2A to 2C are views which illustrate one example of the ink tank 111 to be installed on the tank holder shown in Figs. 1A and lB. Fig. 2A is a 3 perspective view which shows the ink tank 11iiI, observed in the direction toward the second pawl 132. Fig. 2B is a perspective view which shows the ink tank 111 observed in the direction toward the movable lever 130.

Also, Fig. 2C is a cross-sectional view which shows the ink tank 111.

As shown. in Figs. 2A and 2B, on one side face of the ink tank iii, the movable lever 130 is arranged with the first pawl 131. On the other side face of the ink tank 11iii, there are arranged the second pawl 132 that engages with the second hole 242 of the tank holder 103, and the third pawl 133 that abuts upon the upper end 142 of the tank holder 103. The first pawl 131 and the second pawl 132 engage with the first hole 241 and the second hole 242 formed on the tank holder 103 (see Fig. 10), respectively, when the ink tank 111 is installed on the tank holder 103. In this manner, the ink tank 111 is fixed to the tank holder 103. On the lower face of the ink tank 111, the ink supply port 211 is arranged to protrude from that face cylindricallY.

Also, as shown in Fig. 2C, in the interior of the ink tank 111, the ink absorbent 136 is housed to retain ink by the absorption of ink which is liquid. In the interior of the ink supply port 221, the joint member 154 is filled to be joined with the ink absorbent 136.

When the ink tank 111 is installed on the tank holder 4 103, ink retained in the ink absolvent 136 is supplied to the ink jet head 102 from the ink supply port 211 through the joint member 154.

Figs. 3A to 3D are views which illustrate the procedures to install the ink tank on the tank holder 103.

At first, as shown in Fig. 3A, the face of the ink tank 111 on the ink supply port 211 side is directed to the upper surface of the tank holder 103. At the same time, the second pawl 132 of the ink tank 111 is inclined downward. Then, the ink tank is being inserted into the interior of the tank holder 103.

At this juncture, if the ink tank 111 is installed in the diagonal direction as shown in Fig. 3B, the third pawl 133 abuts upon the upper end 143 of the tank holder 103 before the outer circumference of the ink supply port 211 abuts upon the joint member 204 of the head cartridge. Thus, the outer circumference of the ink supply port 211 is prevented from being in contact with the joint member 204. In this manner, the normal setting operation is promoted.

Then, as shown in Fig. 3C, the ink tank is inserted along the inclined face of the tank holder 103 on its side indicated on the right-hand side in Fig.

3C. Here, the second pawl 132 of the ink tank 111 is at first engages with the second hole 242 of the tank holder 103.

5 Further, as shown in Fig. 3D, the ink tank 111 is pressed into the tank holder 103 so that the movable lever 130 is bent to the inner side to enable the first pawl 131 to engage with the first hold 241 of the tank holder 103. Thus, the ink tank 111 is fixed to the thank holder 103. Also, the third pawl 133 is set in the inner side of the tank holder 103 which is inclined to the outer side.

In this state, ink retained in the ink absorbent 136 is introduced into the ink jet head 202 through the joint member 137 of the ink supply port 211. Then, by the application of energy generated by the electrothermal transducing devices (not shown), ink is discharged from the discharge ports (not shown).

In this respect, when the ink tank 111 is removed, the movable member 130 is bent to the inner side to enable the first pawl 131 to be released from the first hole 241 of the tank holder 103. Then, the ink tank 111 is easily removed from the tank holder 103.

In this way, as shown in Figs. IA to 2C, the combination of the ink tank and the recording head provided with the tank holder makes it easier to attach to or detach from each other by the installation method as shown in Figs. 3A to 3D. Then, ink is reliably supplied to the recording head in the state of the ink tank being installed on the recording head. Now that these requirements are satisfactorily met, this 6 combination is excellent in its practical use.

Nevertheless, as a result of ardent studies of the inventors hereof, it has been found that if the following operations should be carried out, there is a fear that the installation is not made exactly as anticipated, although such installation is not among the operations which are fundamentally expected.

At first, as shown in Fig. 4A, if it is attempted to install the ink tank 111 on the ink holder 103 by holding the ink tank in the horizontal posture and lowering it straightly in such condition. Then, as shown in Fig. 4B, the second pawl 132 is pressed by the side face slightly above the second hole 242 of the tank holder 103, and the first pawl 131 of the movable lever 130 is also caused to stay at the side face slightly above the first hole 241 to make it difficult to press the ink tank 111 any further. As a result, there is a fear that the ink supply port 211 does not join the joint member 204 exactly as anticipated.

Further, even when it becomes difficult to press the ink tank 111 any more as described above, the first pawl 131 of the movable lever 130 still resides in a position slightly above the first hole 241 of the tank holder 103 as shown in Fig. 5. Therefore, if the user presses the ink tank forcefully, the first pawl 131 is allowed to engage with the first hole 241 eventually.

As a result, the user may be misled, and commits himself to the wrong recognition as to the installation of the ink tank.

Also, depending on the configuration of a tank holder, the corner portions of the lower face of the ink tank or the leading end of the ink supply port is allowed to slip into the gap in front of the joint when the user intends to install the ink tank by inclining it at a specific angle for the installation on the tank holder. As a result, the installation is not made exactly as anticipated.

Further, as shown in Fig. 1A, if a plurality of ink tanks each having different kind of ink retained in it are arranged to be installed on the tank holder, these erroneous installation also present problems discussed above.

Thus a need clearly exists for an ink tank and an ink jet head cartridge capable of installing the ink tank on the ink jet heat safely without any difficulties in a simple and inexpensive method. Further, a need clearly exists for an ink jet recording apparatus provided with such inkjet head cartridge.

[R:\LIBU]6?475.doc:mic SUMMARY OF THE INVENTION According to an aspect of the present invention there is provided an ink jet head cartridge comprising: an ink tank to retain ink; an ink tank holder to hold said ink tank detachably, having a joint connected with the ink supply port of said ink tank, a first hole to engage with a first pawl of said ink tank, and a second hole to engage with a second pawl of said ink tank on the side face opposite to the side having said first hole; and a recording head unit for discharging ink supplied from said ink supply port, wherein a semicircular rib having a bow-shaped curving face intersecting the inserting direction of said ink tank is arranged on the circumference of said joint of the tank holder for guiding said ink supply port of the ink tank, and a linear rib is arranged to be coupled with said semicircular rib on the side opposite to said joint.

[R-1UBU67525doc nic Other objectives and advantages besides those discussed above will be apparent to those skilled in the art from the description of a preferred embodiment of the invention which follows. In the description, reference is made to accompanying drawings, which form a part hereof. Such example, however, is not exhaustive of the various embodiments of the invention, and therefore reference is made to the claims which follow the description for determining the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1A and lB are views which illustrate one example of the conventional tank holder. Fig. 1A is a perspective view, and Fig. IB is a cross-sectional view; Figs. 2A, 2B and 2C are views which illustrate one 10 example of the ink tank installed on the tank holder shown in Figs. 1A and IB; Figs. 3A, 3B, 3C and 3D are cross-sectional views which illustrate the state in which the ink tank shown in Figs. 2A, 2B and 2C is installed on the conventional tank holder shown in Figs. 1A and IB; Figs. 4A and 4B are views which illustrate the case where the ink tank shown in Figs. 2A, 2B and 2C is held in the horizontal posture and installed on the tank holder shown in Figs. 1A and 1B by being lowered straightly in such posture; Fig. 5 is a cross-sectional view which shows the state where the ink tank shown in Figs. 2A, 2B and 2C cannot be installed appropriately on the tank holder shown in Figs. IA and 1B; Fig. 6 is a perspective view which illustrate the front side of the ink tank and the tank holder that constitute the ink jet head cartridge for black use in accordance with a first embodiment of the present invention; Fig. 7 is a perspective view which illustrate the back side of the ink tank and the tank holder that constitute the ink jet head cartridge for black use in accordance with the first embodiment of the present invention; Fig. 8A is a top view which shows the tank holder in accordance with the first embodiment of the present 11 invention, and Figs. 8B, 8C and 8D are cross-sectional views which schematically illustrate the effect of the tank holder; Figs. 9A, 9B, 9C, 9D, 9E and 9F are views which illustrate the state in which the ink tank is being installed on the tank holder for the ink jet head cartridge for black use in accordance with the first embodiment of the present invention; Figs. 10A and 10B are views which illustrate the case where the ink tank shown in Fig. 6 is held in the horizontal posture, and installed on the tank holder shown in Fig. 6 by lowering it straightly in such posture; Fig. 11 is a perspective view which illustrate the front side of the ink tank and the tank holder that constitute the ink jet head cartridge for color use in accordance with a second embodiment of the present invention; Fig. 12 is a perspective view which illustrate the back side of the ink tank and the tank holder that constitute the ink jet head cartridge for color use in accordance with the second embodiment of the present invention; Fig. 13 is the top view which shows the tank holder in accordance with the second embodiment of the present invention; Figs. 14A and 14B are views which schematically 12, illustrate a tank holder in accordance with a third embodiment of the present invention; Fig. 15 is a view which illustrate the ink tank and the tank holder that constitute an ink jet head cartridge in accordance with a fourth embodiment of the present invention; Fig. 16 is a view which illustrate the ink tank and the tank holder that constitute an ink jet head cartridge in accordance with a fifth embodiment of the present invention; Fig. 17 is a view which illustrate the ink tank and the tank holder that constitute an ink jet head cartridge in accordance with a sixth embodiment of the present invention; Fig. 18 is a perspective view which illustrate the monochromatic tank holder of the head cartridge, and a large capacity ink tank, as well as a small capacity ink tank in accordance with a seventh embodiment of the present invention; Figs. 19A and 19B are plan views which illustrate the state where the large capacity ink tank (small capacity ink tank) is installed on the monochromatic tank holder shown in Fig. 18; and Fig. 20 is a perspective view which schematically shows the ink jet recording apparatus to which the present invention is applicable.

13 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, with reference to the accompanying drawings, the description will be made of the embodiments in accordance with the present invention.

In this respect, the so-called ink having colorants contained in it, which is retained in the ink tank, is exemplified for the description of the embodiments. However, the liquid retained in the ink tank of the present invention is not necessarily limited to ink. All the liquids that can be discharged from the recording head are included. To be more specific, there may be included the processing liquid or the like which enhances the waterproof capability on a recording medium when reacted to other liquid (or ink) on the paper sheet or other recording medium or during the liquid discharge. Now, therefore, in the specification hereof, the term "ink" is used collectively for the liquids that can be discharged from the recording head, such the processing liquids described above.

(First Embodiment) Fig. 6 is a view of the head cartridge for black use in accordance with a first embodiment of the present invention, which is observed from the diagonally upper right front side. Fig. 7 is a view of the head cartridge for black use, which is observed from the diagonally lower left back side.

Ii+ The head cartridge for black use of the present embodiment, which is shown in Fig. 6 and Fig. 7, is structured with a large capacity ink tank 30 for use of black ink, and the tank holder 36 for black use which is provided with the ink jet head 29, and arranged to detachably hold the ink tank 30. On one side face of the ink tank 30, the movable lever 31 is arranged together with the nip 54 and the first pawl 32. On the other side face of the ink tank 30, the second pawls 33a and 33b are provided. Further, above the second pawls 33a and 33b on the other side face of this ink tank 30, the third pawls 34a and 34b are provided.

On the lower part of the ink tank 30,,there are provided the ink supply port 35 which cylindrically protrudes from the bottom face of the tank; the position pin 37 used when the ink tank 30 is installed on the tank holder 36; and the prism 28 used for detecting the ink remainders in the tank.

Also, for the tank holder 36, the first hole 26 and the second holes 38a and 38b are formed with which the first pawl 32 and the second pawls 33a and 33b engage, respectively, when the ink tank 30 is installed on the tank holder 36. Further, for the tank holder 36, the third holes 39a and 39b are formed where the third pawls 34a and 34b are allowed to fall into them once, respectively, for positioning during the installation process of the ink tank 30 on the tank 15 holder 36. Further, on the lower part of the tank holder 36, the positioning hole 27 is arranged to enable the positioning pin 37 of the ink tank 30 to be fitted.

Fig. 8A is the top view of the tank holder. For the tank holder 36, there is further arranged the joint for use of ink supply, which is coupled with the ink supply port 35 of the ink tank 30. Then, in the vicinity of the region on the first hole 26 side, the semicircular rib 11 is arranged as the guide rib provided with the bow-shaped curve which is directed to intersect the insertion of the tank, and also, the linear rib 12 is arranged to be positioned on the side opposite to the joint that engages with the convex portion of the semicircular rib. With the provision of the semicircular rib 11 and the linear rib 12, the leading end of the ink supply port 35 of the ink tank abuts upon the leading end of the linear rib 12 of the tank holder 36 as show in Fig. 8B which is the section taken along line A-A in Fig. 8A even if the ink tank 30 is inserted into the tank holder 36 with an extreme inclination. Then, the ink tank moves in the direction indicated by an arrow so that the ink supply port 36 moves toward the semicircular rib 11. In this manner, only the end portion of the ink supply port of the ink tank abuts on the linear rib 12 and the semicircular rib 11. Consequently, there is no 16 possibility that the leading end of the tank and the end portion of the ink supply port are allowed to slip into the gap in front of the joint of the tank holder, thus causing an inappropriate installation to occur.

Thereafter, as shown in Fig. 8C, the ink tank 30 abuts upon the side face of the tank holder 36 on the right side. Then, as shown in Fig. 8D, the ink tank 30 is fixed to the tank holder 36. In this state, the ink supply port 35 is coupled with the joint 10 reliably.

As clear from Figs. 88 to 8D, the effect that may be produced only by the provision of the semicircular rib and the linear rib is not directed related to the presence or absence of the third pawl.

Here, in accordance with the present embodiment, the movable lever and the engaging pawl (the second pawl) are formed integrally with the tank main body by means of molding. For the mold formation material, polypropylene is adopted, because it has excellent ink resistance, gas-barrier capability, and transparency, and also, it is inexpensive.

Now, in conjunction with Figs. 9A to 9D, the description will be made of the installation (setting) procedures of the ink tank on the tank holder of the ink jet head cartridge further in detail.

At first, as shown in Figs. 9A and 9B, the user directs the face of the ink tank 30 on the ink supply port 35 side toward the upper surface of the tank 17 holder 36. At the same time, he places the second pawls 33a and 33b of the ink tank 30 to be inclined downward, and begins to insert the ink tank 30 into the interior of the tank holder 36.

Then, as shown in Figs. 9C and 9D, the ink tank is inserted along the inclined surface of the tank holder 36 on the right side face in Figs. 9C and 9D to enable the third pawls 34a and 34b of the ink tank to engage with the third holes 39a and 39b of the tank holder 36, and the second pawls 33a and 33b of the ink tank 30 with the second holes 38a and 38b of the tank holder 36. In this case, the engagement between the third holes 39a and 39b and the third pawls 34a and 34b is made to perform the function of the guide required to operate the rotation of the ink tank 30 exactly later with the positions of the second holes 38a and 38b as the fulcrum thereof.

After that, with the second pawls 33a and 33b which have engaged with the second holes 38a and 38b of the tank holder 36 as the fulcrum, ink tank 30 is being rotated, and the ink tank 30 is pressed into the tank holder 36. In this manner, as shown in Fig. 9E and 9F, the movable lever 31 is bent inward. Then, at the same time that the first pawl 32 engages with the first hold 26 of the tank holder 36, the positioning pin 37 of the ink tank 30 is fitted into the positioning hole 27 of the tank holder 36. Hence, the ink tank 30 is fixed to Is the tank holder 36 in good precision.

In this state, ink retained in the ink absorbent is introduced to the ink jet head 29 through the joint member 56 of the ink supply port 35, and discharged from the discharge ports (not shown) by the application of energy generated by the electrothermal transducing devices (not shown) in the head 29, In this respect, when the ink tank 30 is removed, the movable lever 31 is bent inward to withdraw the first pawl 32 from the first hole 26 of the tank holder 36. Then, the nip 54 of the movable lever 31 is pulled up to remove the ink tank 30 from the tank holder 36 easily.

Here, the positioning pin 37 is positioned in the vicinity of the prism 28. The positioning pin is arranged, in particular, in order to locate the prism 28 between the positioning pin 37 and the second pawls 33a and .33b, which become the engagement fulcrum at the time of the ink tank installation. In this way, it becomes possible to enhance the portioning precision of the direction of the horizontal rotation of the prism 28 (in the vertical direction on the surface of Fig. 6 and Fig. 7 to be described later) centering on the second holes 33a and 33b.

Also, the plane of the positioning pin 37 on the second pawls 33a and 33b side is made to be an abutting portion. In this manner, the plane portion is provided 19 for the side face of the positioning hole 27 of the holder 36 so that the abutting portion of the positioning pin 37 is received by the surface or line, but not just a point. With this arrangement, the positioning precision of the ink tank is enhanced still more. Here, with the combination of each structure including the semicircular rib and the linear rib, a higher effect is produced with respect to the enhancement of the positioning precision in which the ink tank of the kind is installed on the tank holder.

Now, in conjunction with Figs. 10A and 10B, the description will be made of the structure that prevents the ink tank from being erroneously installed on the tank holder of a head cartridge.

Figs. 10A is a cross-sectional view which shows the case where the large capacity ink tank 30 for black use shown in Fig. 6 is held in the horizontal posture, and installed on the tank holder 36 by lowering it straightly in such posture. Fig. 10B is a crosssectional view which shows the state where the ink tank kept in the posture shown in Fig. 10A is installed on the tank holder.

As shown in Fig. TOA, the distance is defined as W between the side wall of the tank holder 36 where the first hole 38 is arranged to engage with the first pawl 32 of the movable lever 31 provided for the one side face of the ink tank 30, and the side wall of the tank 20 holder 36 on which the second hole 38a (38b) is arranged to engage with the second pawl 33a (33b) on the side face opposite to the side face where the movable lever of the ink tank 30 is provided.

Further, as shown in Fig. 10B, the distance is defined as S between the outer side face of the base 31a which becomes the bending point of the warping of the movable lever 31 arranged on one side face of the ink tank 30, and the leading end of the second pawl 33a (33b) on the side face opposite to the side where the movable lever 31 of the ink tank 30 is provided.

Then, the distance S for the ink tank 30 is set greater than the distance W for the tank holder 36.

In accordance with the present embodiment, the following dimensional values are adopted: S 72.0 0.1 mm, W 71.4 0.1 mm Here, ink tanks are manufactured by way of trail with various changes of the difference between the distance S for the ink tank 30 and the distance W for the tank holder 36. Then, with the experiments by the actual installation thereof, it has been determined that the difference of 0.4 to 1.0 mm demonstrates the best condition. In other words, if the difference is small than 0.4 mm, the ink tank 30 is held to reside in the position in the half-finished manner as shown in Figs. 4A and 4B (the position which the user tends to erroneously recognize as if the ink tank were installed -21 appropriately). If, on the contrary, the difference is more than 1.0 mm, it becomes difficult to insert the second pawl 33a (33b) into the second hole 38a (38b) of the tank holder 36.

Now, in accordance with the present embodiment, the sectional configuration (the length of the extrusion) of the second pawl 33a (33b) is formed to be shorter on the lower side, and the lower side and the upper side are continuous on the inclined surface as shown in Fig. 9B or Fig. Thus, by making the lower side of the second pawl 33a (33b) longer, it becomes possible to let the user recognize without fail that the installation status is inappropriate, because the first pawl and the second pawl are caught by the tank holder if the ink tank is held in the horizontal posture and the installation is intended on the tank holder from immediately above it in the condition that the ink tank is kept in such horizontal posture.

Here, when the installation is made appropriately, the upper side of the second pawl 33a (33b) advances from diagonally above to the second hold 38a (38b) of the tank holder. However, the upper side and the lower side are in the same length or the structure is arranged to make the upper side longer than the lower side, the upper side of the second pawl 33a (33b) may be in contact with the upper surface of the second hold 22 38a (38b) earlier, and such contact may impede the insertion thereof any further.

Therefore, the upper side of the second pawl 33a (33b) is made shorter than the lower side. Then, the insertion is made easier from diagonally above without letting the upper side of the second pawl 33a (33b) abut upon the second hole 38a (38b) when ink tank is installed. In this way, it becomes possible to make the rotational insertion with a part of the upper side of the second pawl 33a (33b) as the fulcrum assuredly.

As described above, the lower side of the second pawl 33a (33b) is longer, while the upper side thereof is made shorter, and then, the structure is arranged so that the lower side and the upper side is made continuous by means of the inclined surface. The ink tank is prevented from being installed on the tank holder in the wrong direction, and the normal installation is easily carried out without fail. These two functions are made executable satisfactorily at the same time.

Since the structure is formed as described above, the second pawl 33a (33b) is blocked in a position considerably above the second hole 38a (38b) of the tank holder 36 even if it is intended to install the ink tank 30, which is held in the horizontal posture as shown in Fig. 10A, on the tank holder 36 by lowering it straightly as it is as shown in Fig. 10B. The first 2 pawl 32 of the movable lever 31 is also blocked on the outer side of the tank holder 36 considerably above the first hold 38. Then, it becomes difficult to press the ink tank any further. Even if it is pressed down forcefully, the first pawl 32 is not allowed to engage with the first hole 38. Therefore, the use can recognize that the ink tank is not installed on the tank holder exactly. In this way, the user is prompted to operate again in order to install the ink tank correctly.

Also, it is preferable to make the height y of the second pawl 33a (33b) higher than the height x of the third pawl 34a (34b). This is because if the height x of the third pawl 34a (34b) is made equal to or higher than the height y of the second pawl 33a (33b), it becomes difficult for the third pawl to perform its function of guide as shown in Figs. 9C and 9D or the pawl is stuck out to the outer side of the tank holder 36, and may undesirably interfere with the guide shaft of a printer in some cases (see the reference numeral 105 in Fig. In accordance with the present embodiment, the height y of the second pawl is 2.3 mm to 2.5 mm, while the height x of the third pawl is 1.7 to 2.0 mm. The second pawl is higher than the height x of the third pawl by to 0.8 mm.

Here, in accordance with the present embodiment of the invention as described above, it is attempted to solve the subjects of the invention hereof by the adoption of the structure described above for the second engaging pawl. With the application of the structure of the present invention to the ink tank which is provided with the prism and the positioning pin, it is possible to demonstrate further effects as given below.

For example, the cartridge for black use shown in Fig. 6 and Fig. 7 is provided with the prism for use of the remainders detection in the ink tank, and the positioning pin 37 for positioning the ink tank when it is installed on the tank holder.

If the ink tank having the second pawl of the present invention is applied to the ink tank structured as described above, it becomes possible to prevent any forceful operation of ink tank installation. Then, the damage that may be caused to the positioning pin following the forceful installation is minimized.

Therefore, even when the attaching and detaching operations are repeatedly performed, the damage to the positioning pin is controlled to maintain the highly precise tank installation. This is more preferable for the mode in which the presence or the absence of liquid in the ink tank is detected by the remainders detection mechanism provided with the prism and the light emitting means and photodetection means which are 25 externally arranged (a recording apparatus main body or the like) as shown in Fig. 6 and Fig. 7, because such mode requires more rigid precision of the installed position of the ink tank on the tank holder.

(Second Embodiment) Fig. 11 is perspective views which illustrate the front side of the ink tank and the tank holder that constitute the ink jet head cartridge for color use in accordance with a second embodiment of the present invention, observed from diagonally right upper front side. Fig. 12 is perspective views which illustrate such ink tank and tank holder, observed from diagonally left lower back side.

The head cartridge for color use shown in Fig. 11 and Fig. 12 is provided with a cyan ink tank 40c, a magenta ink tank 40m, an yellow ink tank 40y, and the ink jet head, and it is structured with a tank holder 46 which can detachably hold each of the ink tanks and 40y. In the same manner as to the ink tank for black used described above, on one side of each of the color ink tanks 40c, 40m, and 40y, each of the movable levers 41c, 41m, and 41y is arranged. Each of the movable levers is provided with each of the nips 54c, 54m, and 54y, and each of the first pawls 42c, 42m, and 42y, respectively.

On the other side face of each of the color ink tanks 40c, 40m, and 40y, each of the second pawls 43c, 16- ,43m, and 43y is arranged. Further, on the other side of each of the color ink tanks 40c, 40m, and 40y, the third pawls 44c, 44m, and 44y are arranged above the second pawls 43c, 43m, and 43y, respectively.

On the lower part of the ink tank 40c (40m and there are provided the ink supply port 45c and 45y) which cylindrically protrudes from the bottom face of the tank; the position pin 47c (47m and 47y) used when the ink tank 40c (40m and 40y) is installed on the tank holder 46; and the prism 51c (51m and 51y) used for detecting the ink remainders in the tank.

Also, for the tank holder 46, the first hole 48c (48m and 48y) and the second hole 49c (49m and 49y) are formed with which the first pawl 42c (42m and 42y) and the second pawl 43c (43m and 43y) engage, respectively, when the ink tank 40c (40m and 40y) is installed on the tank holder 46. Further, for the tank holder 46, the third holes 50c (50m and 50y) is formed where the third pawl 44c (44m and 44y) is allowed to fall into it once, respectively, for positioning during the installation process of each ink tank on the tank holder 46.

Further, on the lower part of the tank holder 46, the positioning hole 53c (53m and 53y) is arranged to enable the positioning pin 47c (47m and 47y) of the ink tank 40c (40m and 40y) to be fitted.

In this manner, each of the ink tanks is detachably installed on the tank holder. Then, each of 7 the ink tanks is made exchangeable, thus reducing the running costs of printing operation of an ink jet recording apparatus.

In accordance with the present embodiment, too, there are provided, as in the first embodiment, the semicircular rib 14 (14y, 14m, and 14c) and the linear rib 15 (15y, 15m, and 15c) on the side of the joint 13 (13y, 13m, and 13c) of the tank holder 46 as clear from the representation of the tank holder 46 on the top view shown in Fig. 13. Therefore, the use can easily install the ink tanks on the tank holder.

Also, the distance S (see Fig. 10) between the outer side face of the base portion of the movable lever of the ink tank and the leading end of the second engaging pawl is set is set greater than the distance W (see Fig. 10) between the inner side faces of the side wall having the first engagement hale and the side wall having the second engagement hole of the tank holder.

Then, unless the correct operation is carried out, the ink tank is not fixed to the tank holder because the tank does not engage with the holder. With a simple and an inexpensive method, it becomes possible to let the user install the ink tank on the tank holder correctly and safely without difficulty.

Now, the detailed description will be made of the structure adopted for preventing the erroneous installation of the ink tank of the present embodiment, 28 and the ink tank of the first embodiment.

As shown in Fig. 6, two engaging pawls (the second pawls) 33a and 33b are provided for one side face (back face) of the large capacity ink tank 30 for black ink use of the first embodiment. Further, above each of the second pawls 33a and 33b in the vertical direction on the same side face, the tired pawls 34a and 34b are arranged, respectively. Further, on the side face (front face) opposite to the side face where the second pawls 33a and 33b are provided, the first pawl 32 is arranged for the movable lever 31. For the tank holder 36, there are arranged the second holes 38a and 38b, and the third holes 39a and 39b to receive the second pawls 33a and 33b, and the third pawls 34a and 34b, respectively.

Now, each length of the second pawls 33a and 33b of the ink tank 30 in the transverse direction (the width direction of the ink tank) is defined as La, and the gap between the second pawls 33a and 33b is defined as Lc. Also, each length of the second holes 38a and 38b of the tank holder 36 in the transverse direction (the width direction of the tank holder) is defined as Ma, and the gap between the second holes 38a and 38b is defined as Mc.

Then, the length Ma of the second hole is made longer than the length La by 0.02 to 0.12 mm so as to enable the second pawls 33a and 33b to be inserted into 29 the second holes 38a and 38b.

For the present embodiment, the following dimensional values are adopted: La 2.920 to 2.970 mm, Lc 9.0 0.1 mm Ma 3.000 to 3.050 mm, Mc 9.0 0.1 mm Also, as shown in Fig. 11, the engaging pawls (the second pawls) 43y, 43m, and 43c are provided for one side face (back face) of each of the ink tanks and 40c for color use of the second embodiment.

Further, above each of the second pawls 43y, 43m, and 43c in the vertical direction on the same side face, the tired pawls 44y, 44m, and 44c are arranged, respectively. Further, on the side face (front face) opposite to the side face where the second pawls 43y, 43m, and 43c are provided, the first pawls 42y, 42m, and 42c are arranged for the movable levers 41y, 41m, and 41c, respectively. For the tank holder 46, there are arranged the second holes 49y, 49m, and 49c, and the third holes 50y, 50m, and 50c to receive the second pawls 49m,49m, and 49c, and the third pawls 50y, and 50c, respectively.

Now, each length of the second pawls 43y, 43m, and 43c of each of the color ink tanks 40y, 40m, and 40c is the same, respectively, in the transverse direction (the width direction of the ink tank), and defined as Le, and each length of the second holes 49y, 49m, and 49c of the tank holder 46 is the same, respectively, in 30 the transverse direction (the width direction of the tank holder) and defined as Me.

Then, the length Me of the second hole is made longer than the length Le by 0.02 to 0.12 mm so as to enable the second pawls 43y, 43m, and 43c to be inserted into the second holes 49y, 49m, and 49c.

For the present embodiment, the following dimensional values are adopted: Le 6.920 to 6.970 mm Me 7.000 to 7.050 mm With the structure described above, if the relationship of Lc 2La Me and/or Lc Me is satisfied at least, there is no possibility that the second pawls 33a and 33b of the large capacity ink tank 30 for black ink use are allowed to engage with the second holes 49y, 49m, and 49c of the tank holder 46 for color use. Also, if the relationship of Le Ma or Mc Le is satisfied, there is no possibility that each of the second pawls 43y, 43m, and 43c of the ink tanks 40y, 40m, and 40c for color use is allowed to engage with the second holes 38a and 38b of the tank holder 36 for black ink use.

In this way, it is made possible for the user to recognize the position where the ink tank should be installed on the tank holder exactly.

(Third Embodiment) Figs. 14A and 14B are cross-sectional views which 31 illustrate the principal part of the ink jet head cartridge in accordance with a third embodiment of the present invention. 'The present embodiment is the variational example of the first embodiment. For the parts where no variation is made, the same reference marks are applied. Then, the description thereof will be omitted.

In accordance with the present embodiment, the semicircular rib and the linear rib are changed. Fig.

14A shows the state where each height of the semicircular rib lla and the linear rib 12a is arranged to become lower gradually as each of them approach the joint 10 more closely. Fig. 14B shows the state where each height of the semicircular rib ilb and the linear rib 12b is arranged to become higher gradually on the contrary.

Even if the configuration of the installing ink tank is complicated, it is possible to install the ink tank smoothly on the tank holder either in one of the modes shown in Fig. 14A and Fig. 14B.

(Fourth Embodiment) Hereunder, the description will be made of the structure with which the user is allowed to recognize whether or not plural kinds of ink tanks are correctly installed on the tank holder for color use which forms the head cartridge for color use.

Fig. 15 is a view which shows the head cartridge 32 for color use in accordance with a fourth embodiment of the present invention, observed from diagonally lower left back face.

Although described in conjunction with the second embodiment, on each one side face (back face) of the ink tanks for color use 40y, 40m, and 40c the engaging pawls (the second pawls) 43y, 43m, and 43c are arranged as shown in Fig. 6. Further, above the second pawls 43y, 43m, and 43c in the vertical direction on the same side face, the third pawls 44y, 44m, and 44c are arranged. Further, on the side face (front face) opposite to the side where the second pawls 43y, 43m, and 43c are arranged, the first pawls 42y, 42m, and 42c are arranged for the movable levers 41y, 41m, and 41c.

On the tank holder 46, the second holes 49y, 49m, and 49c, and also, the third holes 50y, 50m, and 50c are arranged to receive the second pawls 43y, 43m, and 43c and the third pawls 44y, 44m, and 44c, respectively.

In accordance with the present embodiment, although each length of the second pawls 43y, 43m, and 43c in the transverse direction (the width direction of the ink tank) is the same, each position of the second pawls is changed so that the second pawl for the cyan ink tank 40c is positioned at the right end toward the back face; the one for the magenta ink tank 40m, in the center; and the one for the yellow ink tank 40y, on the left end, respectively. Further, for the third pawls 33 44y, 44m, and 44c positioned above the second pawls 43y, 43m, and 43c in the vertical direction, the positional changes are made likewise per color ink tank. Also, each position of the second holes 49y, 49m, and 49c and the third holes 50y, 50m, and 50c of the tank holder 46 that correspond to the second pawls 43y, 43m, and 43c and the third pawls 44y, 44m, and 44c, respectively, is changed to be on the right end, in the center, and the left end accordingly.

With the structure thus arranged, the second pawl 43y and the third pawl 44y of the yellow ink tank engage only with the corresponding second hole 49y and third hole 50y of the tank holder 46, but do not engage with any other second holes 49m and 49c or the third holes 50m and 50c. The same is applicable to the pawls of the magenta ink tank 40m or the cyan ink tank These are not allowed to engage with the holes unless corresponding to each other.

In other words, the engaging pawl on the back face of each color ink tank is arranged to engage with the hole of the tank holder only in the position determined correctly for each of color ink tanks for the tank holder accordingly. Therefore, it is made possible for the user to recognize whether or not the respective ink tanks are correctly installed on the tank holder.

(Fifth Embodiment) In this respect, too, the description will be made 3Wtof the structure as the variational example of the fourth embodiment, with which the user is allowed to recognize whether or not plural kinds of ink tanks are correctly installed on the tank holder for color use which forms the color head cartridge. Also, here, the aspects which are different from those of the fourth embodiment will be described.

Fig. 16 is a view which shows the head cartridge for color use in accordance with a fifth embodiment of the present invention, observed from diagonally lower left back face.

Although as described in Fig. 16, each length of the second pawls 43y, 43m, and 43c of the color ink tanks 40y, 40m, and 40c is the same in the transverse direction (the width direction of the ink tank), each position of the second pawls is changed so that the one for the cyan ink tank 40c is deviated to the lower end side on the back face; the one for the magenta ink tank slightly above the cyan tank 40c; and the one for the yellow ink tank 40y, slightly above the magenta tank 40m. Further, above the second pawls 43y, 43m, and 43c in the vertical direction on the same side face, the third pawls 44y, 44m, and 44c are arranged, and for these third pawls, too, the same changes are made per color tank. Also, each position of the second holes 49y, 49m, and 49c and the third holes 50y, and 50c of the tank holder 46 is changed corresponding 35 to the second pawls 43y, 43m, and 43c and the third pawls 44 y, 44m, and 44c accordingly.

With the structure thus arranged, the second pawl 43y and the third pawl 44y of the yellow ink tank engage only with the corresponding second hole 49y and third hole 50y of the tank holder 46, but do not engage with any other second holes 49m and 49c or the third.

holes 50m and 50c. The same is applicable to the pawls of the magenta ink tank 40m or the cyan ink tank These are not allowed to engage with the holes unless corresponding to each other.

In other words, the engaging pawl on the back face of each color ink tank is arranged to engage with the hole of the tank holder only in the position determined correctly for each of color ink tanks for the tank holder accordingly. Therefore, it is made possible for the user to recognize whether or not the respective ink tanks are correctly installed on the tank holder.

(Sixth Embodiment) In this respect, too, the description will be made of the structure as the variational example of the fourth embodiment, with which the user is allowed to recognize whether or not plural kinds of ink tanks are correctly installed on the tank holder for color use which forms the color head cartridge. Also, here, the aspects which are different from those of the third embodiment will be described.

36 Fig. 17 shows the head cartridge for color use in accordance with a sixth embodiment of the present invention, observed from diagonally lower left back face.

A shown in Fig. 17, in accordance with the present embodiment, each pawl configuration of the second pawls 43y, 43m, and 43c of the color ink tanks 40y, 40m, and is changed so that for the one for the cyan ink tank 40c has a convex extrusion in the lower right end of the rectangular parallelepiped; the one for the magenta ink tank 40m, in the lower central portion thereof; and the one for the yellow ink tank 40y, on the lower left end, respectively. Further, above the second pawls 43y, 43m, and 43c in the vertical direction on the same side face, the third pawls 44y, 44m, and 44c are arranged, and for these third pawls, too, the same changes are made per color tank. Also, each configuration of the second holes 49y, 49m, and 49c and the third holes 5 0 y, 50m, and 50c of the tank holder 46 is changed corresponding to the second pawls 43y, 43m, and 43c and the third pawls 44y, 44m, and 44c accordingly.

With the structure thus arranged, the second pawl 43y and the third pawl 44y of the yellow ink tank engage only with the corresponding second hole 49y and third hole 50y of the tank holder 46, but do not engage with any other second holes 49m and 49c or the third -31holes 50m and 50c. The same is applicable to the pawls of the magenta ink tank 40m or the cyan ink tank These are not allowed to engage with the holes unless corresponding to each other.

In other words, the engaging pawl on the back face of each color ink tank is arranged to engage with the hole of the tank holder only in the position determined correctly for each of color ink tanks for the tank holder accordingly. Therefore, it is made possible for the user to recognize whether or not the respective ink tanks are correctly installed on the tank holder.

(Seventh Embodiment) Here, the description will be made of the structure with which the user is able to recognize the erroneous installation for the monochromatic tank holder where one of the ink tanks having different capacities is exchangeably installed.

Fig. 18 is a perspective view which shows the monochromatic tank holder for the head cartridge, and the larger and smaller ink tanks in accordance with a seventh embodiment of the present invention. Fig. 19A is a plan view which shows the state where the larger capacity ink tank is installed on the monochromatic tank holder. Fig. 19B is a plan view which shows the state where a smaller capacity ink tank is installed on the monochromatic tank holder.

In Fig. 18, the ink tank 30 and the ink tank 3S are the same as those of the first and second embodiments. The dimensional values of the second pawls are also the same, respectively.

For the tank holder 86, there are arranged the second holes 88a (right) and 88b (left) to engage with the second pawls 33a and 33b of the ink tank respectively. The second hold 88c (center) is also arranged to engage with the second pawl 43 of the ink tank 40. The dimensional value of the second hole 88a (right) is the same as that of the second hole 38a (see Fig. 7) in accordance with the first embodiment. The dimensional value of the second hole 88b (left) is the same as that of the second hole 38b (see Fig. 7) in accordance with the first embodiment. The dimensional value of the second hole 88c (center) is the same as those of the second holes 49y, 49m, and 49c (see Fig.

12) in accordance with the second embodiment.

With the structure thus arranged, it becomes possible to install both the ink tank 30 and the ink tank 40 on the tank holder 86 correctly as shown in Figs. 19A and 19B. In other words, in accordance with the present embodiment, the user can install plural kinds of ink tanks on one holder correctly.

Now that the principal part of the present invention has been described as above, the description will be made of the ink jet recording apparatus to which each of the embodiments of the invention is sci preferably applicable as given below. Here, unless otherwise stated, each of the embodiments described above or the combination thereof is applicable to the recording apparatus given below.

Fig. 20 is a perspective view which schematically shows the ink jet recording apparatus capable of mounting on it the ink jet head cartridge and the ink tank of the present invention.

For the ink jet recording apparatus shown in Fig.

20, the lead screw 104 and the guide shaft 105, which are arranged to be in parallel to each other, are provided in a housing. For the lead screw 104 and the guide shaft 105, the carriage 101 is movably installed in the direction parallel to the lead screw 104 and the guide shaft 105. The carriage 101 moves in parallel with the lead screw 104 when the lead screw rotates by means of a carriage motor (not shown).

For the carriage 101, the ink jet head cartridge provided with the ink jet head 110 is mounted. In the vicinity of the movement locus plane of the discharge port surface of the ink jet head 110, the sheet pressure plate 109 is arranged.

Also, the ink jet recording apparatus is provided with the sheet feed roller 107 that carries the recording sheet 106 which serves as a recording medium toward the recording area of the ink jet head 110, and the sheet exhaust roller 108 for exhausting the recording sheet 106 after recording by use of the ink jet head 110. The sheet feed roller 107 and the sheet exhaust roller 108 are rotated by means of a motor (not shown).

Ink discharged from the ink jet head 110 adheres to the recording sheet 106 which faces the discharge port surface of the ink jet head 102. Thus, images are recorded on the surface of the recording sheet 106.

Interlocked with the recording to the recording sheet 106 by the ink jet head 102, the recording sheet 106 is exhausted outside the ink jet recording apparatus by the operation of the sheet feed roller 107 and the sheet exhaust roller 108, as well as the sheet pressure plate 109.

In this respect, it may be possible to mount tow different kinds of head cartridges on the carriage of the recording apparatus described above. In this case, provided that the cartridges can mount three color ink tanks each as in the second embodiment, the two head cartridges may be one photographic head cartridge having magenta and cyan tanks for use of lighter density colors, as well as the black ink tank, and one color head cartridge that can discharge yellow, magenta, and cyan ink. With the combination thus arranged, the recording apparatus can print in six ink colors, and also, it can print in the photographic mode or the aforesaid photographic head cartridge may be replaced with the ink tank only for black use as in the first embodiment so that a text printing can be made at higher speeds, and that images are printed in business colors at higher speeds as required.

Claims (3)

1. An inkjet head cartridge comprising: an ink tank to retain ink; an ink tank holder to hold said ink tank detachably, having a joint connected with the ink supply port of said ink tank, a first hole to engage with a first pawl of said ink tank, and a second hole to engage with a second pawl of said ink tank on the side face opposite to the side having said first hole; and a recording head unit for discharging ink supplied from said ink supply port, 0io wherein a semicircular rib having a bow-shaped curving face intersecting the inserting direction of said ink tank is arranged on the circumference of said joint of the tank holder for guiding said ink supply port of the ink tank, and a linear rib is arranged to be coupled with said semicircular rib on the side opposite to said joint.

2. An inkjet head cartridge according to Claim 1, wherein the heights of said semicircular rib and said linear rib are made gradually higher toward said joint side, respectively.

3. An ink jet head cartridge according to Claim 1, wherein the heights of said semicircular rib and said linear rib are made gradually lower toward said joint said, respectively. DATED this first Day of November, 2002 Canon Kabushiki Kaisha Patent Attorneys for the Applicant SPRUSON FERGUSON [R \LJBU]67459 doc:mic