Patent Publication Number: US-7901027-B2

Title: Image forming apparatus, component, component checking method, control program, and storage medium

Description:
This is application is a division of U.S. patent application Ser. No. 11/470,697, filed Sep. 7, 2006. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image forming apparatus and a component used on the image forming apparatus. The present invention also relates to a component checking method to decide whether the component is available for use with the image forming apparatus, a control program to cause a computer to execute the checking method, and storage medium to store the control program. 
     2. Description of the Related Art 
     Generally, image forming apparatus (printing apparatus), such as ink jet printers, have replaceably mounted on their bodies cartridge type components that accommodate consumables, such as ink and print medium (also referred to simply as “cartridges”). Such cartridges are available on the market separate from the image forming apparatus body. Since new products of the image forming apparatus are introduced into the market in a short cycle of every year or half, few improvements on their performances are made after they have been put on the market. Cartridges, on the other hand, continue to be supplied as long as the image forming apparatus using the cartridges are in common use and thus continue to be manufactured and sold for a far longer period than with the image forming apparatus, for example, for more than 10 years. Since the cartridges continue to be manufactured and sold for many years, not a few improvements are made during that period. For example, when a new ink is developed and a cartridge (ink cartridge) accommodating that ink is put on the market, it is often the case that the new cartridge is designed to be able to be used also on old image forming apparatus that were sold in the past so that smooth transition from old cartridges can be made. 
     It is, however, often difficult to design new cartridges to match all image forming apparatus that were using old cartridges. For example, if the image forming apparatus is an ink jet printer, designing an ink ejection control and a recovery device for preventing possible clogging of ink ejection nozzles in a way that match new cartridges is difficult to achieve. Further, since the new cartridge needs to be able to be installed in the image forming apparatus that were sold in the past, new consumables cannot be changed in their shape from old ones. 
     As a technology to solve these problems, Japanese Patent Application Laid-open No. 2000-246921 describes a method of storing in the cartridge and using ID (identification) information. That is, the image forming apparatus checks the ID information stored in the cartridge to prevent an inappropriate cartridge from being mounted on the apparatus. Japanese Patent Application Laid-open No. 2002-225307 discloses a method for storing in the cartridge and using driver information that matches the cartridge. That is, by checking the match or compatibility between the driver information stored in the cartridge and the printer driver in the image forming apparatus, an inappropriate cartridge is prevented from being mounted and used on the image forming apparatus. Further, specifying and using a particular printer driver that match the driver information allows the new cartridge to be used correctly even in the image forming apparatus that were sold in the past. 
     However, with the method described in the Japanese Patent Application Laid-open No. 2000-246921, the image forming apparatus that were sold in the past cannot identify ID information of the new cartridge correctly. Further, in the case of the method described in Japanese Patent Application Laid-open No. 2002-225307, the image forming apparatus sold in the past can correctly identify the new cartridge by checking the driver information against the printer driver. This, however, requires a computer (host device) installed with a printer driver to communicate with the image forming apparatus. In recent years, image forming apparatus are available that are directly connected with a digital camera to print images taken by the digital camera without using the computer. Further, multifunction type image forming apparatus are commonly available which has multiple functions, such as a scanner function, a facsimile function and a copy function. The method disclosed in Japanese Patent Application Laid-open No. 2002-225307 that requires the use of a computer, however, cannot be applied to these image forming apparatus that do not require a computer. 
     SUMMARY OF THE INVENTION 
     An object of this invention is to provide an image forming apparatus capable of correctly checking a compatibility between the image forming apparatus and a component that can be mounted on the apparatus, a component, a functional component checking method, a control program, and storage medium. 
     In the first aspect of the present invention, there is provided an image forming apparatus using a mountable component to realize a desired function, comprising: 
     a mounting portion for mounting the component preliminarily provided with first information as its identification information and second information as identification information of at least one image forming apparatus that can use the component; 
     storage means for storing third information as identification information of the image forming apparatus and fourth information as identification information of at least one component that can be used on the image forming apparatus; 
     recognizing means for recognizing the first and second information provided to the component mounted on the image forming apparatus; and 
     decision means for deciding that, when the fourth information includes the first information or when the second information includes the third information, the component mounted on the image forming apparatus can be used, and deciding that, when the fourth information does not include the first information and the second information does not include the third information, the component mounted on the image forming apparatus cannot be used. 
     In the second aspect of the present invention, there is provided a component mounted and used in an image forming apparatus recognizing first and second information provided in the component and storing third and fourth information, the third information being identification information of the image forming apparatus, the fourth information being identification information of at least one component that can be used on the image forming apparatus, 
     wherein the component is preliminarily provided with its identification information as the first information and identification information of at least one image forming apparatus that can use the component as second information; wherein, when the component can be used in the image forming apparatus, the first information is included in the fourth information or the second information includes the third information; 
     wherein, when the component cannot be used in the image forming apparatus, the first information is not included in the fourth information and the second information does not include the third information. 
     In the third aspect of the present invention, there is provided a decision method to check if a component mounted in an image forming apparatus can be used in the image forming apparatus, the method comprising the steps of: 
     recognizing first and second information provided to the component, the first information being identification information of the component and the second information being identification information of at least one image forming apparatus that can use the component; 
     comparing the first and second information with third and fourth information stored in the image forming apparatus, the third information being identification information of the image forming apparatus and the fourth information being identification information of at least one component that can be used in the image forming apparatus; 
     deciding that, when the fourth information includes the first information or when the second information includes the third information, the component mounted on the image forming apparatus can be used; and 
     deciding that, when the fourth information does not include the first information and the second information does not include the third information, the component mounted on the image forming apparatus cannot be used. 
     In the fourth aspect of the present invention, there is provided a control program to check if a component mounted on an image forming apparatus can be used or not, the control program causing a computer to execute the steps of: 
     recognizing first and second information provided to the component, the first information being identification information of the component and the second information being identification information of at least one image forming apparatus that can use the component; 
     comparing the first and second information with third and fourth information stored in the image forming apparatus, the third information being identification information of the image forming apparatus and the fourth information being identification information of at least one component that can be used in the image forming apparatus; 
     deciding that, when the fourth information includes the first information or when the second information includes the third information, the component mounted on the image forming apparatus can be used and 
     deciding that, when the fourth information does not include the first information and the second information does not include the third information, the component mounted on the image forming apparatus cannot be used. 
     In the fifth aspect of the present invention, there is provided a storage medium storing computer-readable program codes, wherein the storage medium stores the control program of the fourth aspect of the present invention. 
     With this invention, the component stores its identification information (first information) and identification information (second information) of at least one image forming apparatus that can use the component. The image forming apparatus stores its identification information (third information) and identification information (fourth information) of at least one component that can be used in the image forming apparatus. Then, when the fourth information includes the first information or the second information includes the third information, it is decided that the component mounted in the image forming apparatus can be used. When the fourth information does not include the first information and the second information does not include the third information, it is decided that the component mounted on the image forming apparatus cannot be used. 
     As described above, this invention compares the first and second information stored in the component with the third and fourth information stored in the image forming apparatus. This makes it possible to precisely check the compatibility between the image forming apparatus and the component that can be installed in the apparatus. Further, by putting the identification information of the image forming apparatus that were sold in the past in the second information stored in a component that is newly manufactured and marketed, the image forming apparatus capable of using the component can be set freely and correctly without having to modify the image forming apparatus at all. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an outline block diagram of an image forming apparatus in a first embodiment of this invention; 
         FIG. 2  is an outline perspective view of a cartridge that can be mounted on the image forming apparatus of  FIG. 1 ; 
         FIG. 3A  and  FIG. 3B  illustrate a relation between the image forming apparatus of  FIG. 1  and data stored in the cartridge of  FIG. 2 ; 
         FIG. 4  is a flow chart showing a cartridge identifying process in the first embodiment of this invention; 
         FIG. 5  is a flow chart showing a cartridge identifying process in a second embodiment of this invention; 
         FIG. 6  is a flow chart showing processing executed by a host computer in the second embodiment of this invention; 
         FIG. 7  illustrates an example of content shown on a display portion during the processing of  FIG. 6 ; and 
         FIG. 8  is an outline perspective view showing an example image forming apparatus that can be applied to the present invention. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Now, embodiments of the present invention will be described by referring to the accompanying drawings. It should be noted that concepts included in the following embodiments may not necessarily be described in the scope of claims. Such concepts, however, are not deliberately excluded from the technical scope of the invention and may be in an equal relationship with the invention. 
     First Embodiment 
     As a first embodiment of this invention, a case will be described in which a cartridge (ink cartridge) accommodating ink is mounted as a component on an image forming apparatus (printing apparatus) that forms an image using ink. It is noted, however, that this invention does not limit the number of cartridges mounted on the image forming apparatus to only one. The cartridge is not limited to only those ink cartridges containing ink but may be those accommodating a variety of kinds of consumables, such as print medium. The cartridge is only one form of the component and may be storage medium storing programs and data used on the image forming apparatus. 
     Among ink cartridges that may be mounted on the image forming apparatus, there is a 2-cartridge type that separately accommodates a black (K) ink and color inks such as cyan (C), magenta (M) and yellow (Y) inks. An individual type ink cartridge is also available which individually and separately accommodates all C, M, Y and K inks and other inks. Whatever the type of ink cartridges, the image forming apparatus normally does not perform an image forming operation unless all the ink cartridges mounted are usable. Therefore, in an image forming apparatus in which a plurality of ink cartridges are installed, processing described later is executed for all ink cartridges and, only if all the ink cartridges are found to be usable, can the image forming apparatus operate normally. 
       FIG. 8  is an outline perspective view showing an example construction of an image forming apparatus that can apply the present invention. The image forming apparatus of this example is an ink jet printing apparatus of serial scan type in which an ink cartridge  54  and an ink jet print head are removably mounted on a carriage  53  that reciprocally moves in a main scan direction of arrow A. The ink cartridge  54  accommodates ink as consumable. The ink jet print head can eject ink supplied from the ink cartridge  54  from a plurality of nozzles and use electrothermal transducers (heaters) and piezoelectric devices as a means for generating ink ejection energy. When the electrothermal transducers are used, a bubble is formed in ink by the heat of the electrothermal transducer and the expanding bubble expels the ink from the nozzle. The ink cartridge  54  may be one that forms an ink jet cartridge together with ink jet print head. 
     The carriage  53  is guided along guide shafts  51 ,  52  so that it can be moved in the main scan direction of arrow A. The carriage  53  is reciprocally moved in the main scan direction by a carriage motor and a drive force transmission mechanism such as a belt for transmitting the drive force of the motor. Paper P as a print medium, after being inserted into an insertion opening  55  provided at the front end of the apparatus, is inverted in its transport direction and fed by a feed roller  56  in a subscan direction of arrow B. The printing apparatus  50  repetitively alternates a printing operation and a feeding operation to print images successively on the paper P. The printing operation at this time involves ejecting ink toward a print area on the paper P on the platen  57  while moving the print head  10  in the main scan direction. The feeding operation feeds the paper P in the subscan direction a distance corresponding to a print width of the image printed by the printing operation. 
     At a left end of the travel range of the carriage  53  in  FIG. 8  is installed a recovery system unit (recovery processing means)  58  that faces a nozzle forming surface of the print head  10  mounted on the carriage  53 . The recovery system unit  58  is provided with a cap capable of capping the nozzles and a suction pump capable of introducing a negative pressure into the cap. The recovery system unit  58  introduces the negative pressure into the cap, that closes the nozzles, to suck out ink from the nozzles to maintain the good ink ejection state of the print head  10  (this recovery operation is also called a “suction-based recovery operation”). Further, the recovery operation to maintain the good ink ejection state of the print head  10  can also be performed by ejecting ink that does not contribute to forming images from the nozzles into the cap. 
       FIG. 1  is a block configuration diagram of a control system in the image forming apparatus  100  of this embodiment. 
     The image forming apparatus  100  can be constructed in a manner similar to the ink jet printing apparatus of  FIG. 8 . An image forming portion  109  in the image forming apparatus  100  executes an image forming operation. In the case of the ink jet printing apparatus of  FIG. 8 , the image forming portion  109  includes a mechanical portion required to print an image by causing the ink jet print head to eject ink as the print head moves relative to the paper P. The mechanical portion includes a carriage motor to drive the carriage  53  in the main scan direction, a paper feed motor to transport the paper P in the subscan direction, and a motor driver for these motors. 
     A communication portion  101  of the image forming apparatus  100  communicates with a host computer (host device)  200 , such as a personal computer, and a digital camera through USB and IEEE 1394. A control portion  102  is a processor that controls the operation of the entire apparatus according to a control program stored in a ROM  104 . The ROM  104  is a nonvolatile read only memory device and stores ID information of the image forming apparatus  100  and a control program to cause the control portion  102  to execute processing described later. A RAM  105  is a volatile memory device which is used as a work area by the control portion  102  during the execution of control processing and to temporarily store various data. A PROM  106  is a nonvolatile rewritable memory device and stores cartridge ID information described later. 
     A cartridge mounting portion  103  has a connector for a cartridge connecting terminal  302  of a cartridge C described later to read and write information to and from a storage device  301  of the cartridge C. In the case of the ink jet printing apparatus of  FIG. 8 , the ink cartridge  54  is equivalent to the cartridge C and the cartridge mounting portion  103  is equivalent to the ink cartridge  54  mounting portion in the carriage  53 . 
     A display portion  107  informs the user of the state of the image forming apparatus by means of LED and liquid crystal panel. The communication portion  101 , control portion  102 , cartridge mounting portion  103 , ROM  104 , RAM  105 , PROM  106 , display portion  107  and the image forming portion  109  communicate through a common bus  108 . The ROM  104  may be eliminated and its function may be covered by the PROM  106 . The information that can be stored in the ROM  104  may all be stored in the PROM  106 . 
     A host computer  200  has a RAM  201 , a control portion  202 , a communication portion  203 , an external storage device  204  and a display portion  205 , all interconnected through a bus  206 . 
       FIG. 2  is a perspective view showing an outline construction of the cartridge C in this embodiment. The cartridge C accommodates consumables, such as ink and print medium. The cartridge  C  of this example is an ink cartridge accommodating ink as with the ink cartridge  54  of  FIG. 8 . 
     The cartridge C of this example has a body  300  accommodating ink and a storage device  301 , such as IC chip, to store information. The storage device  301  is connected with a cartridge connecting terminal  302  that can be connected to the cartridge mounting portion  103  of the image forming apparatus  100 . Information exchange between the storage device  301  and the image forming apparatus  100  may also be realized by using a noncontact type radio-based communication means, rather than the above-described contact type communication means. 
       FIG. 3A  and  FIG. 3B  show information stored in the PROM  106  of the image forming apparatus  100  and in the storage device  301  of the cartridge C. 
     The PROM  106  has written therein ID information (third information) D 3  of the image forming apparatus  100  itself and ID information (fourth information) D 4  of at least one cartridge C that can be used in the image forming apparatus  100 . In  FIG. 3A  and  FIG. 3B , “B” is written as the ID information (third information) D 3  of the image forming apparatus  100 . As the ID information (fourth information) D 4  of the cartridge C that can be used on the image forming apparatus  100 , “1” is written in the PROM  106  of  FIG. 3A  and “1” and “2” are written in the PROM  106  of  FIG. 3B . The image forming apparatus  100  is shipped with the ID information D 3 , D 4  written into the PROM  106  as described above. There is a case where the ID information D 3  of the image forming apparatus  100  does not need to be rewritten. In that case, the ID information may be stored in the ROM  104  (see  FIG. 1 ). 
     The storage device  301  of the cartridge C has ID information (first information) D 1  of the cartridge itself and ID information (second information) D 2  of at least one image forming apparatus  100  that can use that cartridge C. In  FIG. 3A  and  FIG. 3B , “2” is written as the ID information (first information) of the cartridge C, and “A” and “B” are written as the ID information (second information) of the image forming apparatus  100  that can use the cartridge C. The cartridge C is shipped with the ID information D 1 , D 2  written into the storage device  301 . 
     In this example, ID information D 1  of the cartridge itself and ID information D 2  of at least one image formation apparatus  100  that can use the cartridge C are stored in the storage device  301  of the cartridge C. ID information D 1 , D 2  may be barcode, such as two-dimensional barcode, attached to the cartridge, that can be read by an optical sensor. The present invention is also practicable in this case. Further, the present invention is practicable in a case in which ID information D 1 , D 2  are coded in alphanumeric characters and printed on a package (outer case) of the cartridge. The alphanumeric characters are input by using an operating portion of the image formation apparatus by user, and processing shown in  FIGS. 4 and 5  described later are performed for input alphanumeric characters as ID information D 1 , D 2 . 
       FIG. 4  is a flow chart showing example processing in this embodiment to identify a cartridge. This identification processing is executed by the control portion  102  according to the control program stored in the ROM  104  of the image forming apparatus  100 . 
     First, in step S 600  the image forming apparatus  100  reads from the cartridge C mounted in the cartridge mounting portion  103  ID information (cartridge ID) as the first information D 1  that is stored in the storage device  301 . In step S 601 , a check is made as to whether the cartridge ID (fourth information D 4 ) is stored in the PROM  106  of the image forming apparatus  100 . If it is stored there, the cartridge ID (fourth information D 4 ) is read out from the PROM  106  (step S 602 ). Then, a decision is made as to whether the cartridge ID (fourth information D 4 ) read from the PROM  106  agrees with the cartridge ID (first information D 1 ) of the cartridge C (step S 603 ). If they agree, the image forming apparatus  100  now can use the cartridge C mounted thereon. Therefore, in this case the identification processing is terminated. 
     In the decision of step S 603 , if the cartridge IDs fail to agree, the processing returns to step S 601  where it checks if there is any cartridge ID (fourth information D 4 ) that has yet to be read out. If there is any cartridge ID (fourth information D 4 ) remaining to be read out, the cartridge ID is read out and then the processing of step S 602  and S 603  is executed. If there is no cartridge ID yet to be read out, ID information (image forming apparatus ID (third information D 3 )) of the image forming apparatus  100  itself is read out as the third information D 3  from the ROM  104  of the image forming apparatus  100  (step S 604 ). 
     In the next step S 605 , it is checked whether an image forming apparatus ID (second information D 2 ) is stored in the storage device  301  of the cartridge C. If the image forming apparatus ID is stored, it is read out (step S 607 ) to determine whether the image forming apparatus ID (second information D 2 ) agrees with the image forming apparatus ID (third information D 3 ) read out from the ROM  104  of the image forming apparatus  100  (step S 608 ). If they agree, the image forming apparatus  100  is allowed to use the cartridge C mounted thereon. In this case, the processing proceeds to step S 609  where it writes the cartridge ID of the cartridge C as the fourth information D 4  into the PROM  106  of the image forming apparatus  100  before ending this identification processing. 
     If, for example, the relation between the image forming apparatus  100  and the cartridge C is as shown in  FIG. 3A , the cartridge ID “2” of the cartridge that can be used is not stored in the fourth information D 4  of the PROM  106  of the image forming apparatus. However, the second information D 2  of the storage device  301  of the cartridge C is written with the image forming apparatus ID “B” of the image forming apparatus that can use that cartridge C. In such a case, in the image forming apparatus  100  having “B” as the image forming apparatus ID, step S 608  decides that the apparatus  100  can use the cartridge C with its ID of “2”. Then, step S 609 , as shown in  FIG. 3B , writes a new cartridge ID of “2” into the fourth information D 4  of PROM  106  of the image forming apparatus  100 . 
     If the image forming apparatus IDs fail to agree in the decision of step S 608 , the processing returns to step S 605  and checks if there is any image forming apparatus ID (second information D 2 ) that has yet to be read out. If there is any image forming apparatus ID remaining to be read out, the ID is read out and then steps S 607  and S 608  are executed. If there is no ID remaining to be read out, the cartridge C mounted on the image forming apparatus  100  cannot be used in that apparatus. In this case, the identification processing informs the user of the image forming apparatus  100 , before exiting the processing, that the installed cartridge C is not compatible with the image forming apparatus  100 . The method of notification in that case may involve, for example, blinking an LED on the display portion  107  in a manner different from the normal one or displaying character strings on a liquid crystal panel. 
     Second Embodiment 
     The image forming apparatus of the first embodiment is so constructed as to be able to check if a variety of kinds of cartridges including new cartridges can be used or not. Further, without changing such a basic construction, it is possible to prompt the user to update software (driver) that instructs the image forming apparatus to perform the image forming operation. Cartridges having IDs different from those of conventionally used cartridges are often those cartridges (such as ink cartridges) accommodating consumables with different characteristics from the conventional ones. Such a case mostly requires a printer driver (software) different from that of the conventional cartridge. Normally, the printer driver is installed in the host computer  200  and is used to control the image forming apparatus  100 . 
       FIG. 5  is a flow chart showing an example of cartridge identification processing in the second embodiment of this invention. 
     Steps from S 600  to S 609  are the same as those of the first embodiment. In this embodiment, step S 610  following step S 609  causes the image forming apparatus  100  to notify the host computer  200  connected to the communication portion  101  of the apparatus  100  that a new cartridge has been mounted on the image forming apparatus  100 . That is, when, with the cartridge mounted, a new cartridge ID is written into the PROM  106  (step S 609 ), the cartridge is recognized as a new cartridge and information indicating this fact is informed to the host computer  200 . 
       FIG. 6  is a flow chart showing example processing that the host computer performs when it receives the above notification. 
     First, in step S 700  the computer receives information notified by the communication portion  203  of the image forming apparatus  100 . Then, it checks if the notified information indicates that a new cartridge has been mounted (step S 701 ). If the notified information indicates the mounting of a new cartridge, the computer prompts by the display portion  205  the user to update the printer driver (step S 702 ).  FIG. 7  shows an example notification prompting the user to update the printer driver. When a dialog, such as shown in  FIG. 7 , is displayed and if the user selects a button representing “update”, a Web browser such as Internet Explorer and Netscape is started to display a Web page to download the printer driver. The user can download the printer driver from the Web page to the host computer  200 . 
     The procedure of  FIG. 6  is stored as software in the external storage device  204  of the host computer  200  and is read out by the control portion  202  into the RAM  201  and then executed by the control portion  202 . 
     Other Embodiments 
     In the above embodiments, the cartridge ID of a new cartridge that has been verified to be compatible or usable is written into the PROM of the image forming apparatus in order to simplify the subsequent identification processing. However, a person skilled in the art will understand that this writing operation is not always necessary. That is, the operation to write the cartridge ID of the new cartridge which is verified to be usable into the PROM of the image forming apparatus is simply an option. 
     The present invention can be applied widely to various kinds of apparatus to which a cartridge can be mounted. The cartridges may be those that accommodate various kinds of consumables. For example, they may be an ink cartridge accommodating ink and a cartridge accommodating print paper. Not only can the cartridges accommodate the consumables used in the image forming apparatus (printing apparatus), but it they may also be components that store information (including program and data) used in the image forming apparatus. 
     Further, this invention is not limited to only the serial scan type printing apparatus described above but may be applied to a variety of image forming apparatus. The printing method is not limited to only the ink jet method and may be of any type. 
     The present invention can be widely applied to an information processing system comprised of a plurality of devices such as a host computer and an image forming apparatus, and to an information processing system comprised of a single device such as an image forming device. More specifically, the present invention can be applied to scanners, printers, personal computers, copying machines, composite machines, and facsimiles. That is, the present invention can be applied widely to various kinds of apparatus equipped with a cartridge. 
     The present invention can also be realized by other methods than executing the control program stored in the ROM  104  of the image forming apparatus  100  by the control portion  102 . For example, a computer incorporated into the image forming apparatus  100  or a host computer (host device)  200 , which together with the image forming apparatus  100  forms an image forming system, may read and execute program codes of software programs supplied from outside to realize the present invention. The software programs are those which realize individual functions of the embodiments described above (programs correspond to the flow charts shown in  FIG. 4  and  FIG. 6 ), and can be supplied directly or remotely to a system or apparatus. Therefore, the program codes themselves that are installed in a computer to implement the functions/processing of this invention by the computer are among the constitutional elements of this invention. That is, the computer programs themselves to implement the functions/processing form one invention. In that case, the programs may be in any form, for example, object codes, programs executed by an interpreter, or script data to be supplied to an operating system. 
     Storage medium that may be used to supply the programs include, for example, flexible disks, hard disks, optical discs, magnetooptical discs, MOs, CD-ROMs, CD-Rs, CD-RWs, magnetic tapes, nonvolatile memory cards, ROMs, and DVDs (DVD-ROMs and DVD-Rs). 
     Other methods for supplying programs include connecting to a home page on the Internet by using a browser of a client computer. In that case, computer programs of this invention or compressed files including an automatic install function can be downloaded from a connected home page into storage medium such as hard disk. It is also possible to divide program codes making up the programs of this invention into a plurality of files and to download these files from different home pages. That is, WWW servers that allow the program files, used to realize processing functions of this invention by the computer, to be downloaded to a plurality of users also form constitutional elements of this invention. 
     The processing functions of this invention can also be realized by encrypting the programs of this invention, storing the encrypted programs in storage medium, such as CD-ROMs, and distributing them to users. In that case, users who have cleared predetermined conditions are allowed to download decryption key information from the home page through the Internet and use that decryption key information to execute the encrypted programs and thereby install them in the computer. 
     In addition to executing by the computer the program read out, the functions of this invention can also be realized by the operating system on the computer executing a part or all of the actual processing according to instructions of that program. 
     Further, it is also possible to use a memory in a function expansion board inserted in the computer or a memory in a function expansion unit connected to the computer. That is, after the program read out from the storage medium is written into these memories, the CPU in the function expansion board or function expansion unit executes a part or all of the actual processing according to instructions of the program. This processing can also realize the functions of this invention. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2005-260871, filed Sep. 8, 2005, which is hereby incorporated by reference herein in its entirety.