Abstract:
An ink container detachably mountable to a recording head, the recording head including an ink jet recording chip which is driven by a driving voltage supplied through a driving voltage wiring lead and an electric signal supplied through an electric signal wiring lead to eject ink, an electrical opening portion provided in at least one of the driving voltage wiring lead and the electric signal wiring lead, the ink container includes a connection element for establishing electrical connection by electrically closing the electrical opening portion when the ink container is mounted to the recording head.

Description:
FIELD OF THE INVENTION AND RELATED ART  
       [0001]     The present invention relates to an ink jet recording apparatus, an ink jet recording head, and an ink container, for recording on a recording medium by ejecting ink from the recording head.  
         [0002]     An ink jet recording apparatus is a recording apparatus of a so-called nonimpact type, being characterized in that it generates virtually no noise while recording, and also, that not only is it capable of recording at a high speed, but also, it is capable of recording on various types of recording medium. Thus, an ink jet recording apparatus is widely employed as an apparatus which bears the role of the recording mechanism in an image forming apparatus such as a printer, a copying machine, a facsimileing machine, a wordprocessor, etc.  
         [0003]     As the representative ink ejecting systems for a recording head to be mounted in an ink jet recording apparatus, those which employ electromechanical transducing elements such as piezoelectric elements, those which irradiate ink with electromagnetic waves, such as laser light, in order to eject ink droplets by utilizing the effect of the heat generated in the ink, those which heat ink with the use of electrothermal transducing elements having heat generating resistor(s), in order to eject ink droplets by utilizing the so-called film boiling phenomenon, etc., have been known.  
         [0004]     Among the above described ink ejecting systems, the ink ejecting system (recording head) which employs electrothermal transducing elements is as follows: An electrothermal transducing element is placed in a recording liquid chamber. The ink in the recording ink chamber is heated (thermal energy is given to ink) by supplying the electrothermal transducing element with electric pulses as recording signals to change the ink in phase, so that the bubble pressure generated as the recording liquid changes in phase from the liquid state to the gas state, that is, as the recording liquid boils, is used to eject the recording liquid (ink) from minute ejection orifices to record on recording medium. Generally, a recording head employing electrothermal transducing elements comprises nozzles having an ejection orifice through which ink droplets are ejected, ink passages through which ink is supplied to the nozzles, and a common liquid chamber.  
         [0005]      FIG. 20  is a perspective view of a typical ink jet recording apparatus in accordance with the prior art. The recording apparatus  115  has a recording head  102 , an ink container unit  103 , a paper conveying roller  4 , a carriage  5 , a motor  6 , etc. The paper conveying roller  4  is driven by the motor  6 . A recording medium P is conveyed by the paper conveying roller  4  at an optional pitch. The ink container unit  103  has four ink containers which contain black, cyan, magenta, and yellow inks, for example, one for one. The ink container unit  103  is mounted, along with the recording head  102 , on the carriage  5 , and is moved along guide rails  7  and  8 , in the direction perpendicular to the direction in which the recording medium P is conveyed. Ink is ejected from the recording head  102  by electrical signals sent and driving voltage sent from the circuit (unshown) on the main assembly side, forming an image on the recording medium P; recording is made on the recording medium P.  
         [0006]     There are various types of recording head: disposable type recording head, which is integral with an ink container; permanent type recording head, which is separable from an ink container; semipermanent type recording head, which is separable from a recording apparatus as well as an ink container; etc. In recent years, however, the recording heads of the semipermanent and permanent types, which do not need to be discarded after the depletion of the ink in the ink container, have come to be proposed by a greater number than the recording heads of the disposable type, because of environmental concerns, and also, in order to reduce the running cost of an ink jet recording apparatus.  
         [0007]     In the case of an ink jet recording apparatus, the recording head of which is separable from an ink container, it is possible that print signals will be sent to the recording head, which an operator forgot to refit with an ink container while replacing the ink depleted ink container. If print signals are sent to the recording head not fitted with an ink container, the electrothermal transducing elements are driven while no ink is sent to the recording head. As a result, the temperature of the electrothermal transducing elements becomes very high, causing the ingredients, such as dye, pigments, etc., in the small amount of ink remaining in the recording head to be baked onto the surfaces of the electrothermal transducing elements. Once the above-mentioned ingredients of ink are baked onto the surfaces of the electrothermal transducing elements, it is possible that even when the recording head is supplied with ink, the electrothermal transducing elements will fail to normally boil the ink, causing the ink to be abnormally ejected.  
         [0008]     In the case of an ink jet recording apparatus which employs a plurality of independently replaceable ink containers, it is possible for a given ink jet head to be fitted with an incorrect ink container, that is, an ink container which contains such ink that is not intended for the given ink jet head. If an ink jet head is fitted with an incorrect ink container, not only is it impossible to yield the normal results, but also, various other problems occur. For example, in the case that the electrothermal transducing elements in the plurality of ink jet heads different in the color of the inks they use are different in driving requirements, it is possible that ink ingredients will be baked onto the electrothermal transducing elements. Also in the case that an ink container is depleted of ink, an ink jet head cannot be supplied with ink, resulting in the same problems as those which occur when a user forgets to fit an ink jet head with an ink container. Therefore, it is common practice to count the number of ink droplets ejected from an ink jet head, in order to measure the amount of the ink remaining in the ink container. However, the method for estimating the amount of the ink remainder by counting the number of the ink droplets is substantial in error. Therefore, in order to more accurately estimate the amount of the ink remainder, the different types of method for measuring the ink remainder have been proposed. According to one of such methods, the amount of the ink remainder is estimated based on the fact that the manner in which a beam of light projected into an ink container from the main assembly of a recording apparatus is reflected is affected by the presence (or absence) of ink in the ink container. Thus, an ink container is provided with a prism, which is located on the bottom surface of the ink container (for example, Japanese Laid-open Patent Application 218321).  
         [0009]     This method, however, has been suffering from the following problem. That is, even though the recording apparatus is provided with a system for detecting the amount of the ink remainder in an ink container, the system cannot detect whether or not a given ink jet head is fitted with an ink container. Therefore, it is necessary to provide the recording apparatus with a system for detecting whether or not a given ink jet head is fitted with an ink container. Besides, even if a recording apparatus is equipped with a system for detecting whether or not a given ink jet head is fitted with an ink container, the system cannot detect whether or not a given ink jet head is fitted with an ink container, the ink in which is correct in color. Therefore, there is the possibility that the recording apparatus will print abnormal images, and/or the ink ingredients will be baked onto electrothermal transducing elements.  
       SUMMARY OF THE INVENTION  
       [0010]     The present invention was made in consideration of the above described problems, and therefore, its primary object is to provide an ink jet recording apparatus, an ink jet head, and an ink container, which are highly reliable in that if the ink jet head of the ink jet recording apparatus is not fitted with the ink container, or is fitted with an incorrect ink container, the electrothermal transducing elements are prevented by a simple and reliable method from being driven, preventing thereby ink ingredients from being baked onto the heater.  
         [0011]     According to an aspect of the present invention, there is provded an ink container detachably mountable to a recording head, said recording head including an ink jet recording chip which is driven by a driving voltage supplied through a driving voltage wiring lead and an electric signal supplied through an electric signal wiring lead to eject ink, an electrical opening portion provided in at least one of said driving voltage wiring lead and said electric signal wiring lead, said ink container comprising a connection element for establishing electrical connection by electrically closing the electrical opening portion when said ink container is mounted to the recording head.  
         [0012]     According to an further of the present invention, there is provded a recording head according to claim  8 , wherein said electrical opening portion is constituted by electrically insulated two contacts and a switch connected to one of said contacts, wherein said ink container has a projection at a position facing said switch, and wherein when said ink container is mounted to said recording head cartridge, said switch is depressed by said projection to contact to another said contact so that electrical opening portion is electrically closed.  
         [0013]     According to an futher aspect of the present invention, there is provded a recording head cartridge claim  8 , wherein said electrical opening portion is constituted by electrically insulated two contacts, and said ink container has a connection wiring lead at a position facing both of said contacts, and wherein when said ink container is mounted to said recording head cartridge, said connection wiring lead contacts both of said contacts to close said electrical opening portion.  
         [0014]     According to a further aspect of the present invention, there is provded a recording device wherein by detecting presence or absence of electrical conduction at the electrical opening portion of said recording head cartridge, presence or absence of a mounted ink container which is to close said electrical opening portion.  
         [0015]     An electrothermal transducing element does not function unless it is supplied with both driving voltage and an electrical signal. Therefore, the problem that an electrothermal transducing element is driven while an ink jet head is not in connection with an ink container, and/or that ink ingredients are baked onto an electrothermal transducing element by an excessive amount, can be prevented by structuring an ink jet recording apparatus so that at least one of the driving voltage and electrical signal is not supplied unless an ink jet head is in connection with an ink container.  
         [0016]     An ink jet recording apparatus which employs multiple ink containers different in the color of the ink they contain can be structured so that one or both of the electrical wire for the driving voltage and the electrical wire for electrical signal are provided with a single or multiple electrically open (discontinuous) portions, based on the color of the ink. It may be structured so that the multiple ink containers different in the color of the inks they contain are different in at least one of the position and configuration of the electrically open (discontinuous) portion and connective element.  
         [0017]     The electrically open portion can be structured as follows: It comprises a pair of contact points which are electrically discontinuous, and a switch connected to one of the two contact points, whereas the connective element comprises a projection, the position of which matches that of the switch. Thus, as an ink container is mounted, the projection presses the switch, causing the switch to contact the other contact point. As a result, the electrically open portion becomes continuous.  
         [0018]     The electrically open portion may be structured as follows: It comprises a pair of contact points which are electrically discontinuous, whereas the connective element comprises a connective wire, the ends of which match in position to the pair of contact points of the electrically open portion. Thus, as an ink container is mounted, the ends of the connective wire come into contact with the two contact points of the electrically open portion, one for one. As a result, the electrically open portion becomes continuous. In the case of this set-up, the two contact points and the end portions of the connective wire may be structured so that they couple with each other.  
         [0019]     The recording apparatus in accordance with the present invention employs the above described recording head cartridge. It detects whether or not the recording head has been fitted with a given ink container, based on whether or not the electrically open portion has been made continuous. Further, it may be designed so that when the electrically open portion is remaining discontinuous, the operation for restoring the recording head performance will not be carried out.  
         [0020]     The recording head chip in accordance with the present invention employs an ink jet recording chip, which ejects ink by being driven by the driving voltage supplied through the driving voltage transmission line, and the electrical signal supplied through the electrical signal transmission line. It removably supports a single or multiple ink containers for supplying ink to the ink jet recording chip having the connective element. At least one of the driving voltage transmission line and electrical signal transmission line is provided with the electrically open portion, the position of which corresponds to that of the connective element, and as the ink container is mounted, the electrically open portion is closed by the connective element.  
         [0021]     These and other objects, features, and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]      FIG. 1  is a schematic perspective view of the recording head cartridge in the first embodiment of the present invention.  
         [0023]      FIG. 2  is a schematic drawing for describing the principle for preventing the malfunction of the ink jet recording chip of the recording head cartridge in  FIG. 1 .  
         [0024]      FIG. 3  is a sectional view of the recording head cartridge at a plane parallel to the side wall of thereof.  
         [0025]      FIG. 4  is a sectional view of the electrically open (discontinuous) portion of the recording head, and its adjacencies, in  FIG. 1 .  
         [0026]      FIG. 5  is a schematic perspective view of the portion of the ink container of the recording head cartridge, which is to face the contact circuit board, showing the general configurations thereof.  
         [0027]      FIG. 6  is a schematic plan view of the portion of the ink container of the recording head cartridge, which is to face the contact circuit board, showing the general configuration thereof.  
         [0028]      FIG. 7  is a schematic perspective view of the portion of the ink container of the recording head cartridge, in the second embodiment, which is to face the contact circuit board, showing the general configuration thereof.  
         [0029]      FIG. 8  is a schematic plan view of the portion of the ink container of the recording head cartridge, in the second and third embodiments, which is to face the contact circuit board, showing the general configuration thereof.  
         [0030]      FIG. 9  is a schematic drawing for describing the principle for preventing the malfunction of the ink jet recording chip of the recording head cartridge in the fourth embodiment of the present invention.  
         [0031]      FIG. 10  is a sectional view of the recording head cartridge in  FIG. 9 , at a plane parallel to one of the side walls thereof.  
         [0032]      FIG. 11  is a schematic plan view of the portion of the ink container of the recording head cartridge, in the fifth embodiment, which is to face the contact circuit board, showing the general configuration thereof.  
         [0033]      FIG. 12  is a schematic plan view of the portion of the ink container of the recording head cartridge, in the sixth embodiment, which is to face the contact circuit board, showing the general configuration thereof.  
         [0034]      FIG. 13  is a perspective view of the ink containers, electrical wires placed on the ink containers, electrical wires placed on the ink jet recording head, and contact portions thereof, in the seventh embodiment of the present invention.  
         [0035]      FIG. 14  is a schematic sectional view of the ink jet recording head, and ink container, in the seventh embodiment of the present invention.  
         [0036]      FIG. 15  is a schematic drawing of the junction between the electrical wires placed on the adjacent two ink containers in accordance with the present invention.  
         [0037]      FIG. 16  is a perspective view of the electrical wires placed on the ink containers, electrical wires placed on the ink jet recording head, and junctions among them, in the eighth embodiment of the present invention.  
         [0038]      FIG. 17  is a perspective view of the electrical wires placed on the ink containers, electrical wires placed on the ink jet recording head, and junctions among them, in the modified version of the eighth embodiment of the present invention.  
         [0039]      FIG. 18  is a perspective view of the ink containers, electrical wires placed on the ink containers, electrical wires placed on the ink jet recording head, and junctions among them, in the ninth embodiment of the present invention.  
         [0040]      FIG. 19  is a perspective view of the electrical wires placed on the ink containers, electrical wires placed on the ink jet recording head, and junctions among them, in the tenth embodiment of the present invention.  
         [0041]      FIG. 20  is a perspective view of a typical ink jet recording apparatus in accordance with the prior art.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0042]     Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the appended drawings. The ink jet recording apparatuses in the following embodiments of the present invention are characterized by their ink jet recording heads and ink containers. The structures of the other portions of the ink jet recording apparatuses are the same as those of the ink jet recording apparatus in accordance with the prior art.  
         [0043]      FIG. 1  is a perspective view of the recording head cartridge in the first embodiment of the present invention. The recording head cartridge  1  has an ink jet recording head (which hereinafter will be referred to as recording head)  2 , and an ink container  3 . The recording head  2  is provided with a pair of ink jet recording chips  4  and  5 , which are on the surface of the recording head  2 , which faces the recording medium P ( FIG. 13 ). The recording chip  4  is a color ink chip, and has a line of cyan ink ejection orifices, a line of magenta ink ejecting orifices, and a line of yellow ink ejecting orifices, whereas the recording chip  5  is a black ink chip having a line of black ink ejecting orifices. The two recording chips  4  an  5  are independently placed.  
         [0044]     The ink jet recording chips  4  and  5  are driven by the electrical signals and driving voltage sent from the main assembly (unshown) of the recording apparatus. They have a heater board (unshown), ink ejection orifices (unshown), and a nozzle plate (unshown). The heater board has multiple electrothermal transducing elements for causing the ink to boil. The ink ejection orifices are the orifices through which ink droplets are ejected by the pressure generated by the boiling of the ink. The nozzle plate has ink passages (unshown) through which ink is supplied to the ink ejection orifices. The ink jet recording chips  4  and  5  are connected to a contact circuit board  7  having electrical contacts through which the chips  4  and  5  are electrically connected to the main assembly of a recording apparatus, through an electrical wire tape  6  having the electrical signal transmission wires for supplying the chips  4  and  5  with the electrical signals from the main assembly, and the driving voltage transmission wires for supplying the chips  4  and  5  with the driving voltage from the main assembly.  
         [0045]     The recording chips  4  and  5  are precisely and solidly attached to a base board  8 , which has ink passages through which the recording chips  4  and  5  are supplied with the ink from an ink container unit  3 . The contact circuit board  7 , electrical wire tap  6 , and base board  8  are solidly attached to a supporting member  9 , which also has ink passages through which ink is supplied from the ink container unit  3  to the ink jet recording chips  4  and  5 , and a filter (unshown) for removing foreign particles from the ink supplied from the ink container unit  3 . A part of the supporting member  9  constitutes an ink container holder  10  into which the ink container unit  3  is mounted. The bottom wall of the ink container holder  10  is provided with holes through which the prisms  14  of the ink containers of the ink container unit  3  are exposed to detect the amount of the ink remainder, or presence (absence) of the ink, in the ink containers of the ink container unit  3 , based on the phenomenon that the reflection of a beam of light projected into the ink containers of the ink container unit  3  from the photosensors on the main assembly side of the recording apparatus is affected by the amount of the ink in the ink containers.  
         [0046]     The ink jet recording apparatuses in the preferred embodiments of the present invention are made up of the main assembly and recording head cartridge. The main assembly of the recording apparatus described in this specification does not include the recording head cartridge. Although the ink container units  3  in the preferred embodiments of the present invention are structured so that they are mounted in a part of the recording head  3 , they may be structured so that they are supported by the carriage  5  ( FIG. 13 ) of the main assembly. Further, the recording heads  2  in the preferred embodiments are structured so that they can be removably mounted into the main assembly. However, they may be structured to be an integral part of the main assembly.  
         [0047]      FIG. 2  is a schematic drawing showing the electrical signal transmission line from the main assembly of the recording apparatus to the ink jet recording chip.  FIG. 2 ( a ) shows the state of the electrical signal transmission line when the ink container unit  3  is not in the ink container holder, and  FIG. 2 ( b ) shows the state of the line when the ink container unit  3  is in the ink container holder. Hereinafter, the present invention will be described with reference to one of the color ink containers (case in which ink jet recording chip  4  is driven).  
         [0048]     Referring to  FIG. 2 ( a ), the electrical signal transmission line  11  through which the electrical signals sent from the main assembly  15  of the recording apparatus are transmitted has three separate electrical wire portions  11   a ,  11   b ,  11   c , and  11   d . The electrical wire portion  11   a  is extended, within the main assembly  15  of the image forming apparatus, from the control portion (unshown) of the main assembly  15  to the contact point  21 , by which the portion  11   a  is connected to the contact point  22  of the contact circuit board  7 . The electrical wire portion  11   b  is extended from the contact point  22  of the contact circuit board  7  to the contact point  23   a  of the contact circuit board  7 , which is on the surface of the contact circuit board  7  facing the ink container unit  3 . The electrical wire portion  11   c  is extended from the contact point  23   b  of the contact circuit board  7 , which is on the surface of the contact circuit board  7  facing the ink container unit  3 , to the contact  24  of the contact circuit board  7  on the ink jet recording chip side. The electrical wire portion  11   d  is extended from the contact point  24  to the ink jet recording chip  4 . The contact point  23   b  is connected to a switch  25 . Sometimes, the combination of the contact points  23   a  and  23   b  and switch  25  may be referred to as electrically open portion.  
         [0049]     The ink container unit  3  is provided with a projection  26 , which is on the surface facing the switch  25 . The projection  26  is a portion for closing (connecting) the electrically open portion, as will be described later. It may be structured so that it also functions as a projection for precisely positioning the ink container unit  3  relative to the ink container holder  10  when the ink container unit  3  is anchored to the holder  10 . It is not in contact with the switch  25 , and the switch  25  is not in contact with the contact point  23   a . It should be noted here that when the recording head  2  is integral with the main assembly  15  of the image forming apparatus, the contacts  21  and  22  are unnecessary.  
         [0050]     Next, referring to  FIG. 2 ( b ), what occurs as the ink container unit  3  is mounted into the ink container holder  10  will be described. As the ink container unit  3  is placed in the predetermined position in the ink container holder  10 , the projection  26  of the ink container unit  3  presses the switch  25 , causing the switch  25  to come into contact with the contact point  23   a , electrically connecting the contact points  23   a  and  23 . As a result, the electrical connection is established from the control portion of the main assembly  15  of the recording apparatus to the ink jet recording chip  4  through the electrical signal transmission line  11  inclusive of the contact points  21 ,  22 ,  23   a ,  23   b , and  24 .  
         [0051]      FIG. 3  is a sectional view of the recording head cartridge, at a plane parallel to the side wall thereof, when the ink container unit  3  is in the ink container holder  10 . This drawing is the sectional view of one of the ink containers of the ink container unit  3  in the recording apparatus, and the sectional views of the other ink containers are the same as  FIG. 3 . As the ink container unit  3  is inserted into the ink container holder  10 , the projection  26  enters the hole of the supporting member  9 , and a latching lever  17  engages with the projection  16  of the ink container unit  3 . As a result, the ink container unit  3  is held to the contact circuit board  7  by the resiliency of the latching lever  17 , and the projection  23  is put through the hole of the supporting member  9 , pressing the switch  25  ( FIG. 4 ) attached to the contact circuit board  7  located on the outward side of the ink container holder  10 .  
         [0052]      FIG. 4  is a schematic sectional view of the electrically open portion of the electrical signal transmission line  11  indicated by a circle in  FIG. 3 .  FIG. 4 ( a ) shows the electrically open portion in the open state, and  FIG. 4 ( b ) shows the electrically open portion in the closed state.  
         [0053]     Referring to  FIG. 4 ( a ), the contact circuit board  7  is connected to the contact point  21  ( FIG. 2 ) of the main assembly  15  of the recording apparatus through the contact  22  of the contact circuit board  7 , being enabled to receive the electrical signals necessary to eject ink from the ink jet recording chip  4 . The contact circuit board  7  is supported by the supporting member  9 , and has the contact points  23   a  and  23   b  and switch  25 , which are on the surface of the contact circuit board  7 , which faces the ink container unit  3 . The switch  25  is attached to the contact point  23   b . Here, the contact point  23   b  means the point of the electrical signal transmission line  11  to which the switch  25  is attached. The switch  25  is formed of electrically conductive and elastic substance, and is structured so that unless external force is applied thereto, it will not come into contact with the contact point  23   a . Thus, before the mounting of the ink container  3  into the ink container holder  10 , the switch  25  is not in contact with the contact point  23   a.    
         [0054]     Next, referring to  FIG. 4 ( b ), as the ink container unit  3  is mounted into the ink container holder  10 , the projection  23  presses the switch  25 , causing the switch  25  to come into contact with the contact point  23   a . As a result, it is made possible, for the first time, for electrical signals to be sent from the main assembly  15  of the image forming apparatus to the ink jet recording chip  4 , through the contact circuit board  7  to drive the electrothermal transducing elements.  
         [0055]     Therefore, if an attempt is made to drive the recording head  2  while the ink container unit  3  is not properly positioned in the ink container holder  10 , the electrical signals outputted from the main assembly  15  of the recording apparatus are not allowed to reach the ink jet recording chip  4 , preventing thereby the electrothermal transducing elements from being driven while ink is not supplied thereto. Therefore, it is possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is highly reliable in that the ink ingredients are unlikely to be baked onto the electrothermal transducing elements of the ink jet recording head.  
         [0056]     Incidentally, in the above, the present invention was described with reference to the electrical signal transmission line. However, the present invention is also applicable to the driving voltage transmission line just as effectively as it is applicable to the electrical signal transmission line. Further, the present invention is also compatible with an ink container for containing black ink. In the case that the present invention is applied to the electrical voltage transmission line, in order to make it possible to detect the presence (or absence) of the ink container unit  3  without the provision of a sensor dedicated to the detection of the presence (or absence) of the ink container unit  3 , the main assembly  15  of the image forming apparatus may be provided with the circuit for detecting whether or not the recording head  2  is being supplied with the power source voltage during the preliminary ejection.  
         [0057]      FIG. 5  is a schematic perspective view of the ink container of the recording head cartridge in the second embodiment of the present invention. This drawing shows the surface of the ink container, which faces the contact circuit board  7 . The ink container unit  3  has four ink containers  3 Y,  3 M,  3 C, and  3 K, in which yellow, magenta, cyan, and black inks are stored, respectively. Each of the four ink containers  3 Y,  3 M,  3 C, and  3 K has a connective projection  28 , by which each ink container is precisely positioned relative to the recording head  2 . The four ink containers  3 Y,  3 M,  3 C, and  3 K are identical in the position and configuration of the connective projection  28 . Further, the four ink containers  3 Y,  3 M,  3 C, and  3 K of the ink container unit  3  are provided with projections  26 Y,  26 M,  26 C, and  26 K, respectively, which are different in the position relative to the ink container which they belong (positions P 1 -P 4 ).  
         [0058]      FIG. 6  is a schematic plan view of the surface of the contact circuit board  7 , which is to face the ink container unit  3 . The contact circuit board  7  is provided with electrically open (discontinuous) portions  27 Y,  27 M,  27 C, and  27 K, which are circled with solid lines in the drawing, and the positions of which correspond to those of the projections  26 Y,  26 M,  26 C, and  26 K of the ink containers of the ink container unit  3 , respectively. The electrically open portions  27 Y,  27 M,  27 C, and  27 K are connected to the electrical signal transmission wires portions  11 Y,  11 M,  11 C, and  11 K, respectively. However, before the ink container unit  3  is mounted into the ink container holder  10 , the electrically open portions  27 Y,  27 M,  27 C, and  27 K remain literally open, keeping the electrical signal transmission line remain discontinuous. Therefore, there is no electrical connection between the main assembly  15  of the image forming apparatus and ink jet recording chip  4 . The portions circled by broken lines on each of the contact circuit boards  7  in  FIG. 6  show the comparative positions of the projections of other contact circuit boards  7 ; no electrically open portion is present on the portion circled by the broken lines. Further, the portions correspondent to the connective projections  28  are not illustrated in  FIG. 6 .  
         [0059]     As an ink container is mounted in the correct position, for example, as an ink container containing yellow ink is connected to the yellow ink ejecting portion of the ink jet recording chip  4 , the electrically open portion  27 Y is closed, electrically connecting the ink jet recording chip  4  to the main assembly  15  of the control portion of the main assembly  15  of the image forming apparatus through the electrical signal transmission line  11 Y, enabling thereby the yellow ink ejection portion of the ink jet recording chip  4  to be driven. However, if an ink container is mounted in an incorrect position, that is, as the ink container  3 M is mounted in the position for the ink container  3 Y, the projection  26 M is not allowed to close the electrically open portion  27 Y. Therefore, no electrical connection is established between the ink jet recording chip  4  and the control portion of the main assembly  15 . Although, in the above, the present invention was described with reference to the electrical signal transmission line, the present invention is just as effectively applicable to the driving voltage transmission line as it is applicable to the electrical signal transmission line.  
         [0060]     Incidentally, the projections  26 Y,  26 M,  26 C, and  26 K are substantially different in the position relative to the ink container to which each of them belongs. However, when there is a spatial restriction in terms of the positioning of the electrical wires, their positions may be varied within a range in which the electrically open portions do not malfunction. Further, an ink container is generally molded with the use of a metallic mold. Thus, molding all ink containers with all projections  26 Y,  26 M,  26 C, and  26 K, and removing the unnecessary projections from each ink container according to the color of the ink for which the ink container is intended, eliminates the need for preparing multiple molds different in configuration, making it possible to reduce an ink container in manufacturing cost.  
         [0061]     As will be evident from the above description of the structural arrangement in accordance with the present invention, if a given ink container is placed in the wrong position in the ink container holder  10  when it is mounted into the ink container holder  10 , the electrical signals and power source are not supplied to the ink jet recording chips from the main assembly  15  of the recording apparatus, making it simple for a user to realize that the given ink container has not been mounted, or that an ink container containing wrong ink has been mounted. Therefore, even in the case of an ink jet recording apparatus employing multiple recording heads different in driving condition (specification), the recording head and ink jet recording chips are not adversely affected. Moreover, an ink jet recording apparatus may be structured so that if an ink container is mounted into the wrong position, the performance recovery operation cannot be carried out. Such an arrangement can minimize the extent of the ink mixture within a recording head, making it possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which are even higher in reliability.  
         [0062]      FIG. 7  is schematic sectional view of the ink container of the recording head cartridge in the third embodiment of the present invention.  FIG. 8 ( a ) is a schematic plan view of the surface of the contact circuit board, which is to face an ink container. In  FIG. 8 ( a ), the portion of the contact circuit board, which corresponds to the connective projection  28  shown in  FIG. 7 , is not shown, and what are meant by the circles drawn by solid lines and broken lines are the same as in  FIG. 6 .  
         [0063]     This embodiment is different from the second embodiment in that the black ink container  3 K is provided with two projections  26 Ka and  26 Kb, and also, that both the signal transmission line and driving voltage transmission line of the contact circuit board  7  of only the black ink container  3 K are provided with the electrically open portion.  
         [0064]     The portions of the contact circuit board  7 , which correspond in position to the projections  26 Y,  26 M, and  26 C of the ink container unit  3 , are provided with the electrically open portions  27 Y,  27 M, and  27 C, respectively. The electrically open portion  27 Ka is located at a position P 1 , and electrically open position  27 Kb is located at a position P 3  (their positions may be reversed). The electrically open portions  27 Ka and  27 Kb correspond to the electrical signal transmission line  11 K, and driving voltage transmission line  12 K, respectively (they may be made to correspond in reverse). Before the mounting of a given ink container into the ink container holder  10 , the electrical signal transmission lines  11 Y,  11 M, and  11 C are prevented by the electrically open portions  27 Y,  27 M, and  27 C, respectively, from transmitting electrical signals, whereas the driving voltage transmission line  12 K is prevented by the electrically open portion  27 Kb from transmitting driving voltage. As for the positions of the projections  26 Ka and  26 Kb, it is desired that two among the positions P 1 , P 2 , and P 3  are selected, in consideration of the above described manufacturing method. However, the positions other than the positions P 1 , P 2 , and P 3  may be selected. Further, the black ink container  3 K may be left with all three projections.  
         [0065]     With the employment of the above described structural arrangement, if an ink container other than the black ink container  3 K is mounted into the position for the black ink container  3 K, the ink in this ink container is not ejected from the ink jet recording chip  5  (black ink ejecting chip), because the ink jet recording chip  5  cannot be driven unless both the electrical signal transmission line  11 K and driving voltage transmission line  12 K are enabled to transmit electrical signals and driving voltage, respectively. Therefore, there is no possibility that the ink ingredients will be baked onto the electrothermal transducing elements, and therefore, there is no possibility that the recording head will be reduced in performance by the ingredients baked onto the electrothermal transducing elements.  
         [0066]     Incidentally, the reason why it is set up so that unless both the electrical signal transmission line  11 K and driving voltage transmission line  12 K are rendered continuous, the electrothermal transducing elements cannot be driven is that if non-black ink enters the ink jet recording chip  5 , which is different from the other ink jet recording chip in the driving condition, there is the possibility that the ingredients in the non-black ink will be baked onto the electrothermal transducing elements of the ink jet recording chip  5 , reducing thereby the recording head in performance. Thus, if an ink jet recording apparatus is designed, for some reason, to employ an ink container which will have substantial adverse effects if it is mounted into a position not intended for this ink container, this ink container may be given the same structure as the above described one.  
         [0067]     Further, when providing a given ink container with two projections  26 , two switches may be serially placed in either the electrical signal transmission line or driving voltage transmission line, instead of assigning the two projections  26  to the electrical signal transmission line and driving voltage transmission line, one for one.  FIG. 8 ( b ) shows an example of such an structural arrangement. For example, the electrically open portion  27   a , which corresponds to the electrical signal transmission line  11 K is located at the position P 1 , and another electrically open portion  27   b , which also corresponds to the electrical signal transmission line  11 K, is located at the position P 3 , so that the two electrically open portions  27   a  and  27   b  are serially positioned in the electrical signal transmission line  11 K. With the employment of such a structural arrangement, the electrical signal transmission line  11 K does not become continuous, unless both the electrically open portions  27   a  and  27   b  are closed. Therefore, this structural arrangement is more reliable than the above described arrangement.  
         [0068]     By changing the number of the projections, and/or switching the projections in position and/or combination, it is possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is highly reliable in that the problem that the ink ingredients are abnormally baked onto the electrothermal transducing elements, or the like problem, does not occur, and also, it is possible to rationalize the manufacturing process.  
         [0069]      FIG. 9  is a schematic drawing of the portion of the electrical signal transmission line of the recording head portion of the ink jet recording apparatus, between the main assembly of the recording apparatus and one of the ink jet recording chips, in the fourth embodiment of the present invention. The fourth embodiment is different from the first embodiment in that a part of the electrical signal transmission line is placed on the ink container.  
         [0070]     FIGS.  9 ( a ) and  9 ( b ) show the states of the electrical signal transmission line before and after, respectively, the ink container is mounted into the ink container holder. Here, the present invention will be described with reference to the electrical signal transmission line.  
         [0071]     Referring to  FIG. 9 ( a ), the electrical signal transmission line  31  through which the electrical signals sent from the main assembly  35  of the recording apparatus are transmitted has four separate electrical wire portions  31   a ,  31   b ,  31   c , and  31   d . The electrical wire portion  31   a  is extended, within the main assembly  35  of the image forming apparatus, from the control portion (unshown) of the main assembly  35  to the contact point  41 , by which the electrical wire portion  31   a  is connected to the contact point  41  of the contact circuit board  37 . The electrical wire portion  31   b  is extended from the contact point  42  of the contact circuit board  37  to the contact point  43   a  of the contact circuit board  37 , which is on the surface of the contact circuit board  37  facing the ink container unit  3 . The electrical wire portion  31   d  is extended from the contact point  43   b , on the surface of the contact circuit board  37  facing the ink container  33 , to the contact point  44  on the ink jet recording chip  4  side. The contact point  31   e  is extended from the contact point  44  to the ink jet recording chip  4 . The ink container  33  is provided with a pair of contact points  45   a  and  45   b , which are on the surface facing the contact circuit board  37 , being positioned so that they come into contact with the contact points  43   a  and  34   b  as the ink container  33  is mounted. The ink container  33  is also provided with an electrical wire portion  31   c , which is connecting the contact points  45   a  and  45   b . The combination of the contact points  43   a  and  43   b  may sometimes be referred to as electrically open portion, whereas the combination of the contact points  45   a  and  45   b  and electrical wire portion  31   c  may be referred to as connective element  48 .  
         [0072]     Before the mounting of the ink container  33 , the contact points  45   a  and  45   b  are not in contact with the contact points  43   a  and  43   b , respectively. Therefore, the electrical signal transmission line  31  is not continuous. As the ink container  33  is mounted, the contact points  45   a  and  45   b  come into contact with the contact points  43   a  and  43   b , respectively, the electrical signal transmission line  31  becomes continuous as it does in the first embodiment.  
         [0073]      FIG. 10  is a sectional view of the recording head cartridge, at a plane parallel to the side walls thereof, after the mounting of the ink container  33 . The contact circuit board  37  fixed to the supporting member  9  is provided with the contact points  43   a  and  43   b  of the electrical signal transmission line  31  through which the electrical signals are sent to the ink jet recording chip  4 . The contact points  43   a  and  43   b  are on the back side of the contact circuit board  37 . Although  FIG. 10  is the sectional view of only one of the ink containers  33 , the other ink containers  33  are the same as the ones shown in  FIG. 10 , in terms of the contact points of the electrical signal transmission line  31 . In this embodiment, the contact points  43   a  and  43   b  are placed on the contact circuit board  37 . However, the locations of the contacts  43   a  and  43   b  do not need to be limited to those in this embodiment. For example, they may be placed on the electrical wire tape  6 . As the ink container  33  is inserted into the ink container holder  10 , a locking claw  46  is put through the hole of the supporting member  9 , causing the latching lever  17  to engage with the projection  16 . As a result, the ink container unit  3  is held to the contact circuit board  7  by the resiliency of the latching lever  17 .  
         [0074]     The electrical signal transmission line  31  is discontinuous between the contact points  43   a  and  43   b . The ink container  33  has the electrical wire portion  31   c  as a part of the electrical signal transmission line  31 . Thus, as the ink container  33  is mounted into the ink container holder  10 , the electrical wire portion  31   c  comes into contact with the contacts  34   a  and  43   b  through the contact  45   a  and  45   b , allowing electrical signals to be sent from the main assembly  35  of the recording apparatus to the ink jet recording chip  4  to drive the electrothermal transducing elements.  
         [0075]     The contact points  43   a  and  43   b , and the contact points  45   a  and  45   b , are structured so that they can be coupled with to each other. For example, the contact point  43   a  may be in the form of a projection, whereas the contact point  45   a  may be in the form of a recess, as shown in  FIG. 10 .  
         [0076]     The electrical wire portion  31   c  is formed of electrically conductive metal, and is integrally formed with the ink container  33  by two color molding when the ink container  33  is molded of resin. The use of two color molding makes it possible to eliminate the labor required to attach the electrical wire portion  31   c  to the ink container  33 . Incidentally, when it is necessary to provide the ink container  33  with a certain amount of strength, the ink container itself, or the external reinforcement jacket therefor, may be formed of electrically conductive metal of high strength. In such a case, the ink container itself can be used as a part of the electrical wire portion  31   c . Obviously, the electrical wire portion  31   c  may be pasted to the external jacket of the ink container  33 .  
         [0077]     As described, with the employment of the above described structural arrangement, if it is attempted to drive the recording head without fitting the recording head with the ink container  33 , the electrical signals outputted from the main assembly  35  of the recording apparatus cannot be sent to the ink jet recording chip  4 . Therefore, it is possible to prevent the electrothermal transducing elements from being driven when ink is not in the ink jet recording head. Thus, it is possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is highly reliable in that there is no possibility that ink ingredients will be baked onto the electrothermal transducing elements by an excessive amount.  
         [0078]     Although this embodiment of the present invention was described, in the above, with reference to the electrical signal transmission line, the effects of the application of the present invention to the driving voltage transmission line is the same as the effects of the above described application of the present invention to the electrical signal transmission wire. Further, although the above description of this embodiment of the present invention was made with reference to an ink container for containing color ink, the effects of the application of the present invention to an ink container for containing black ink is the same as the effects of the above described application of the present invention to the ink container for color ink. In the case of the driving voltage transmission wire, by providing the main assembly of the recording apparatus with a circuit for detecting whether or not the recording head is provided with the voltage from the power source during the preliminary ejection period, it is possible to detect the presence (absence) of the ink container without having a sensor dedicated to the detection of the presence (absence) of an ink container.  
         [0079]      FIG. 11  is a conceptual drawing showing the electrically open (discontinuous) portion of the recording head cartridge in the fifth embodiment of the present invention. This drawing shows the relationship between the electrical signal transmission wire and its contact points, located on the surface of each ink container facing the contact circuit board. The ink container unit  33  has four ink containers  33 Y,  33 M,  33 C, and  33 K, which contain yellow, magenta, cyan, and black inks, respectively. The ink containers  33 Y,  33 M,  33 C, and  33   k  are provided with electrical wire portions  31 Yc,  31 Mc,  31 Cc, and  31 Kc, which are on the surfaces thereof facing the contact circuit board, and the positional relationship of which relative to the ink containers to which they belong are differentiated based on the color of the ink they contain. The electrical wire portion  31 Yc is provided with a pair of contact points  45 Ya, and  45 Yb. Similarly, the electrical wire portion  31 Mc has a pair of contact points  45 Ma and  45 Mb; the electrical wire portion  31 Cc, a pair of contact points  45 Ca and  45 Cb; and the electrical wire portion  31 Kc is provided with a pair of contact points  43 Ka and  43 Kb. The surface of the contact circuit board facing the contact points  45 Ya and  45 Yb is provided with a pair of contact points  43 Ya and  43 Yb. In other words, the electrically open (discontinuous) portion  47 Y and connective element  48 Y are positioned so that they directly oppose each other. This set-up is the same in the case of the ink containers for other colors.  
         [0080]     Before the mounting of the ink containers, the electrical signal transmission lines  31 Y,  31 M,  31 C, and  31 K are kept discontinuous by the electrically open portions  47 Y,  47 M,  47 C, and  47 K, respectively. As the ink container  33 Y, for example, is mounted, the contact points  45 Ya and  45 Yb come into contact with the contact points  43 Ya and  43 Yb, respectively. In other words, the electrically open portion  47 Y comes into contact with the connective element  48 Y, making it possible to drive the yellow portion of the ink jet recording chip  4 .  
         [0081]     However, if an ink container, which is wrong in the color of the ink it contains, for example, an ink container  33 M, is mounted into the position for the ink container  33 Y, the electrically open portion  47 Y does not contact with the connective element  48 M. Therefore, the electrical signal transmission wire  31 Y is not erroneously made continuous. Incidentally, although, in the above, this embodiment of the present invention was described with reference to the electrical signal transmission line, the application of the present invention to the driving voltage transmission line yields the same effect as the above described effect yielded by the application of the present invention to the electrical signal transmission line, as they are in the fourth embodiment.  
         [0082]     The four types of ink containers in this embodiment for four inks of different color, one for one, can be manufactured by pasting four connective elements  48 Y,  48 M,  48 C, and  48 K differentiated based on the color of the inks therein, to four identical base ink containers formed of resin. Therefore, only one type of metallic mold is necessary to manufacture the four types of ink containers, making it possible to easily manufacture the four types of ink containers while minimizing the ink container cost.  
         [0083]     Further, not only can the erroneous mounting of an ink container can be prevented by varying the multiple (four) ink containers in the positions of the electrically open portion and connective element, but also, by varying the multiple (four) ink containers in configuration. In other words, even if the multiple (four) ink containers are identical in the positions of the electrically open portion and connective element, the problem that an ink container for ink of a given color is erroneously mounted into the position for an ink container for ink of another color can be prevented by varying the multiple sets of the electrically open portion and connective element in configuration as described above, for example, giving one set of the electrically open portion a circular shape, and second set a rectangular shape, and so on.  
         [0084]     As described above, if an ink container is erroneously mounted into the position reserved for a specific ink container, the electrical signals and voltage from the main assembly of a recording apparatus are not supplied to an ink jet recording chip. Therefore, it can be easily detected whether or not a given ink container is in the ink container holder, and/or that an ink container is erroneously mounted into the position reserved for a specific ink container. Further, even in the case of an ink jet recording apparatus employing multiple recording heads different in driving condition (varied based on ink color), the recording head and ink jet recording chips are not adversely affected. Moreover, the combination of an ink jet recording apparatus, an ink jet recording head, and an ink container may be designed so that if an ink jet recording head is fitted with an incorrect ink container, it cannot be suctioned for performance recovery. Such a design can minimize the extent of the ink mixture in the recording head, making it possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is even higher in reliability.  
         [0085]      FIG. 12  is a conceptual drawing of the electrically open (discontinuous) portion and connective element of the recording head cartridge in the sixth embodiment of the present invention. This drawing shows the relationship between the electrical signal transmission line and the contact points thereof, placed on the surface of the ink container facing the contact circuit board, as does  FIG. 11 . The ink container unit  53  in this embodiment has four ink containers  53 Y,  53 M,  53 C, and  53 K containing yellow, magenta, cyan, and black inks, respectively, as does the ink container unit in the fifth embodiment. The ink container  53 M is provided with an electrical wire portion  51 Mc and a pair of contact points  65 Ma and  65 Mb, and the ink container  53 C is provided with an electrical wire portion  51 Yc and a pair of contact points  65 Ya and  65 Yb.  
         [0086]     However, the ink container  53 Y is provided with an electrical wire portion  52 Yc of the electrical signal transmission line, and a pair of contact points  65 Yc and  65 Yd, in addition to an electrical wire portion  51 Yc and a pair of contact points  65 Ya and  65 Yb. Therefore, the ink jet recording chip  4  does not function unless both the electrical signal transmission line and driving voltage transmission line of the ink container  53 Y become continuous. In other words, this set-up further raises the level of reliability.  
         [0087]     In addition, the ink container  53 K is provided with a connective element made up of an electrical wire portion  51 Kc and a pair of contact points  65 Ka and  65 Kb, of the driving voltage transmission line  51 K, an a second connective element made up of an electrical wire portion  51 Kc′ and a pair of contact points  65 Kc and  65 Kd. Further, the contact points  65 Kb and  65 Kc are electrically connected to each other within the ink container  53 K. In other words, the electrical wire portion  51 Kc is provided with serially connected two connective elements. Further, the ink container  53 K is provided with an electrical wire portion  53 Kc and a pair of contact points  65 Ke and  65 Kf, of driving voltage transmission line. Therefore, the ink jet recording chip  5  does not function unless both the electrical signal transmission line and driving voltage transmission line of the ink jet recording head become continuous. Also, in order for the electrical signal transmission line  51 K to become continuous, both of the two connective elements have to be placed in contact with the corresponding contact points. Thus, this setup further raises the level of reliability.  
         [0088]     By not only providing the recording heads with electrically open (discontinuous) portions, but also, varying the ink containers in the configuration of electrical wires, number of electrically open portions, and position of the electrically open portion, as described above, it is possible to provide the combination of an ink jet recording apparatus and a recording head cartridge, which is even higher in reliability in that it does not malfunction.  
         [0089]     In the preceding preferred embodiments of the present invention, in the case of an ink jet recording head which employs multiple ink containers, the electrical wires of all the ink containers, and the corresponding portions of the ink jet recording head, have to be provided with electrical contact points. Therefore, each electrical wire has to be made wide enough, at least at one end, to reliably come into contact with the corresponding portions of the ink container. However, widening the electrical wires as described above results in the increase in the electrical wire cost.  
         [0090]      FIG. 13  is a schematic drawing showing the relationship among the ink containers, wires placed on the ink containers, and the contact portions of the electrical contact circuit board of the ink jet recording head. As shown in  FIG. 13 , increasing in size the contact circuit board  204  of the ink jet recording head results in cost increase. Therefore, the contact circuit board  204  is desired to be minimized in size within the range in which it is large enough for a contact pad  209  to be placed electrically in contact with the main assembly. Thus, it sometimes occurs that as the ink containers  207   c ,  207   m ,  207   y , and  207   k  are mounted into the ink jet recording head, the ink containers  207   c  and  207   m , which are mounted in the center portion of the ink jet recording head, are allowed to come into contact with a contact circuit board  204 , whereas the ink container  207   k  and  207   y  are not allowed to come into contact with the contact circuit board  204 , for structural reasons.  
         [0091]     Therefore, in this seventh embodiment, in order to make it possible to detect the presence or absence of all ink containers  207  even if there is such a spatial limitation as the above described one, the driving voltage transmission line  102  is partially placed on the ink containers  207   k  and  207   c , and the ends of the driving voltage transmission line  102  are provided with inter-ink container electrical contact points  106  so that the portions of the driving voltage transmission lines  102  placed on the ink containers  207   k  and  207   c  will be electrically connected. Thus, the driving voltage is transmitted through the portions of the driving voltage transmission lines  102  placed on the ink containers  207   k  and  207   c . Although, in the above described seventh embodiment, the structural arrangement is such that the driving voltage is transmitted through the portions of the transmission lines  102 , the number of the transmission lines  102  may be increased so that the electrical signals from the recording apparatus are also transmitted through the transmission lines  102 . Further, the transmission lines  102  may be extended beyond the edge of the surface of the ink container to which the transmission lines  102  are attached, in parallel to the surface, so that the inter-ink container electrical contact points  106  are attached to the ends of the extended portions, as shown in  FIG. 15 . However, such a structural arrangement makes it possible for the transmission lines  102  to be bent when the ink containers  207  are inserted. Therefore, the structural arrangement such as the one shown in  FIG. 13  is preferable, in which the contact points of the ink container  207   k , and the contact points of the ink container  207   c , are placed on the surfaces of the ink container  207   k  and  207   c  which will oppose each other as the ink containers  207   k  and  207   c  are mounted into the recording head. Moreover, it is desired that the electrical contact points  106  of both the ink containers  207   k  and  207   c  are made elastic to improve the electrical contacts  106  in reliability.  
         [0092]     Next, referring to  FIG. 14 , the contact circuit board  204  and contact portion of the ink container  207  are structured so that contact pins  101   a  and  101   b  through which the driving voltage and electrical signals are sent to the ink jet recording chip are placed on the back side of the contact circuit board  204  solidly fixed to the supporting member  205 . The transmission line on the contact circuit board  204  are discontinuous between the contact points  101   a  and  10   b ; the driving voltage transmission line, or electrical signal transmission line, is discontinuous. Although, in this embodiment, the contact pins are placed on the contact circuit board  204 , this is not mandatory; they may be placed on the electrical wire tape  203 . The ink container  207  is firmly held against the supporting member  205 , and the receptacle in the ink container holder  208 , by the locking claw  103  and the projection of the latching lever  104 . Further, the ink container  207  is kept pressured toward the contact circuit board  204  by the resiliency of the latching lever  104 . As described above, designated by a referential number  102  is a piece of electrical wire. As the contact pins  101   a  and  101   b  are placed in contact with the transmission line  102 , it becomes possible for the data to be sent to the ink jet recording chips  201  and  202  from the ink jet recording apparatus through the contact circuit board, multiple piece of electrical wire placed on the multiple ink containers, etc., to drive the electrothermal transducing elements. In this embodiment, the electrical wire  102  for the ink container  207  is a piece of flexible wire having the contact points to be placed in contact with the contact circuit board  204 , and is pasted on the ink container  207 .  
         [0093]     With all the ink containers  207  structured as described above, if an attempt is made to drive the ink jet recording head when all the ink containers  207  are not in the ink container holder, the driving voltage from the main assembly of the ink jet recording apparatus is not sent to the ink jet recording chip. Therefore, the ink jet recording apparatus is not driven when no ink is in the ink jet recording chip, eliminating the concern that the ink ingredients will be baked onto the electrothermal transducing elements by an excessive amount. Therefore, it is possible to provide a highly reliable ink let recording apparatus without increasing the costs of the contact circuit board or electrical wire tape.  
         [0094]      FIG. 16  is a schematic drawing showing the relationship among the ink containers, electrical wires placed on the ink containers, and contact portions of the contact circuit board of the ink jet recording head, in the eighth embodiment of the present invention. This embodiment is similar to the seventh embodiment, except that this embodiment is smaller in the number of the contact points of the ink jet recording head and ink container than the seventh embodiment. Thus, it is effective when a large area is not available, on the surface of the contact circuit board facing an ink container, for the contact pins, by which the contact circuit board is placed in contact with its counterparts on the ink container. Referring to  FIG. 16 , the ink container unit  701  has four ink containers  701 ,  702 ,  703 , and  704 , which contain yellow, magenta, cyan, and black inks, respectively. Each ink container is provided with an electrical wire  711 , which is on the front surface of the ink container. The electrical wire  711  is provided with a pair of inter-ink container contact points  712 , which are located at the ends of the electrical wire  711 , so that only when all the ink containers are in the ink container holder, the transmission line, inclusive of the electrical wires  711 , becomes continuous. In this embodiment, the electrical wires  711  are used as the parts of the transmission line through which the driving voltage is supplied from the ink jet recording head to the ink jet recording chip. On the ink jet recording head side, the electrical power voltage transmission wire is made discontinuous between the contact points  710   a  and  710   b . The contact pin  710   a  is positioned so that it comes into contact with the electrical wire  711  placed on the ink container  702 , which is to be placed in the center portion of the ink container holder, and the electrical wire of the ink container  702  connected to the contact point  710   a  becomes connected to one end of the electrical wire on the ink container  701 , and the other end of the electrical wire on the ink container  701  become connected to one end of the other electrical wire of the ink container  702 , and so on. As a result, the electrical wires on all the ink containers  701 ,  702 ,  703 , and  704  become connected, and one end of the electrical wire on the ink container  703 , or the other ink container placed in the center of the ink container holder, is placed in contact with the contact pin  710   b . With the employment of the above described structural arrangement, only after the ink jet recording head is fitted with all the ink containers, it becomes possible for the driving voltage from the main assembly of the ink jet recording apparatus to be supplied to the ink jet recording chips through the ink jet recording head. In other words, even though the ink containers and contact circuit board in this embodiment are smaller in the number of the contact points than the ink containers and contact circuit board in the seventh embodiment, the ink jet recording heads are not driven when there is no ink in them, as the ink jet recording heads in the second embodiments are not, eliminating the concern that the ink ingredients are baked onto the electrothermal transducing elements by an excessive amount. Therefore it is possible to provide a highly reliable ink jet recording apparatus.  
         [0095]     In this embodiment, the ink jet recording head is fitted with four ink containers different in the color of the ink they contain. However, the present invention is also applicable to an ink jet recording head to be fitted with six ink containers different in the color of the inks they container, that is, the four ink containers plus two more ink containers, for example, an ink container containing ink of light cyan color, an ink container containing ink of light magenta color, etc.  
         [0096]      FIG. 18  is a schematic drawing showing another embodiment of the present invention, in which the four ink containers are varied in the configuration and position of the electrical wire  811 , and the configuration of the inter-ink container electrical contact points  812 . With the employment of the structural arrangement shown in  FIG. 18 , it is possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is even more reliable in that it is not adversely affected by the insertion of an incorrect ink container.  
         [0097]      FIG. 19  is a schematic drawing showing the relationship among the ink containers, electrical wires placed on the ink containers, contact points of the contact circuit board of the ink jet recording head, in the tenth embodiment of the present invention.  
         [0098]     In this embodiment, ink containers  900 , which are identical in size, configuration, and the pattern of electrical wire  911 , are employed as the base ink containers from which four types of ink containers  901 ,  902 ,  903 , and  904 , the wiring patterns of which are differentiated based on the color of the inks which they are to contain, are manufactured. More specifically, the portions  914  of the electrical wire  911  of each ink container are burned away with the use of a laser, or mechanically removed with the use of a cutter, a drill, or the like, as shown in  FIG. 19 ( b ), in order to give the electrical wire  911  a predetermined pattern which corresponds to the color of the ink it is to contain, that is, the position in the ink container holder, into which it is to be mounted.  
         [0099]     With the employment of the above described manufacturing method, a single mold can be used for manufacturing various types of ink containers, that is, ink containers different in wiring pattern, making it possible to provided a combination of an ink jet recording apparatus, an ink jet head, and an ink container, which is much easier to manufacture, and much lower in cost, than that in the first embodiment.  
         [0100]     As described above, in the case of the recording head cartridge in accordance with the present invention, unless it is correctly fitted with a proper number of correct ink containers, the driving voltage and electrical signals from the main assembly of a recording apparatus are not sent to the ink jet recording chips. Therefore, when no ink is in the recording chips, the electrothermal transducing elements in the ink jet recording chips are not driven. Therefore, the problem that ink ingredients are baked onto the electrothermal transducing elements, or the like problem, does not occur.  
         [0101]     The ink containers are varied in the position of the electrically open portions of the electrical wire placed on each ink container, the configuration of the connective element, and/or the numbers thereof. Therefore, if an ink container incorrect in the color of the ink therein is mounted, the ink jet recording chip is not driven, preventing thereby the electrothermal transducing elements from being adversely affected.  
         [0102]     Further, whether or not the driving voltage and/or electrical signals can be supplied to the recording head can be detected by the main assembly of a recording apparatus, making it thereby possible to detected the presence or absence of a given ink container. Therefore, it is possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is economical and highly reliable.  
         [0103]     Further, with the employment of one or a combination of the above described structural arrangements, unless a proper number of ink containers, which are correct in the color of the inks they container, are mounted into correct positions, one for one, the electrical signal and/or driving voltage from the main assembly of an ink jet recording apparatus are not sent to the recording chips. Therefore, the electrothermal transducing elements in the recording chips are not driven when no ink is in the recording head chips. Therefore, the problem that ink ingredients are baked onto the electrothermal transducing elements, or the like problem, does not occur.  
         [0104]     With the ink containers varied in the pattern, configuration, and position of the electrical wire placed on each ink container, based on the color of the inks contained therein, if an ink container incorrect in the color of the ink therein is mounted, the ink jet recording chips are not driven, preventing thereby the electrothermal transducing elements from being adversely affected. Therefore, it is possible to provide a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is much higher in reliability. Further, it is possible to detect the presence or absence of a given ink container by detecting, on the main assembly side, that electrical power is not being supplied to the ink jet recording heads. Therefore, it is possible to provided a combination of an ink jet recording apparatus, an ink jet recording head, and an ink container, which is inexpensive and highly reliable.  
         [0105]     While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.  
         [0106]     This application claims priority from Japanese Patent Application Nos. 397296/2003 and 308524/2004 filed Nov. 27, 2003 and Oct. 22, 2004, which is hereby incorporated by reference.