Patent Publication Number: US-2023144277-A1

Title: Information processing apparatus and notification method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 17/722175, filed on Apr. 15, 2022, which is a continuation of U.S. patent application Ser. No. 16/909750, filed on Jun. 23, 2020 and issued as U.S. Pat. No. 11,331,928 on May 17, 2022, which claims priority from Japanese Patent Application No. 2019-120952 filed Jun. 28, 2019, which are hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     Field 
     The present disclosure relates to an information processing apparatus and a notification method. 
     Description of the Related Art 
     In an image forming apparatus without a liquid crystal panel or any other display for displaying information, the state of the apparatus is notified to the outside by lighting an indicator light mounted to the apparatus. In Japanese Patent Application Laid-Open No. 2004-188638, there is described a printer apparatus including indicator lamps, which are mounted on a main body of the apparatus, a carriage capable of coming to a stop at any place, and a maintenance cover transmissive of light of the indicator lamps. 
     In the printer apparatus described in Japanese Patent Application Laid-Open No. 2004-188638, it is not easy to check that the indicator lamps are lit through the maintenance cover when the maintenance cover is closed. For instance, when an ink tank is required to be replaced while the printer apparatus is printing, steps of operating the printer apparatus including the opening of the maintenance cover are required in order to correctly recognize which ink tank requires to be replaced. Therefore, it may be difficult to determine which ink tank requires replacing when something hinders a user from operating the apparatus. 
     SUMMARY 
     An aspect of the present disclosure is to provide an information processing apparatus and a notification method with which to alleviate the difficulty of correctly recognizing a tank to be notified when something hinders a user from operating an apparatus. 
     According to at least one embodiment of the present disclosure, there is provided an information processing apparatus having a plurality of liquid tanks, for storing liquids to be ejected onto a recording medium, which are to be loaded, the information processing apparatus including: a state detection unit configured to detect states of the liquids contained in the plurality of liquid tanks; a light emission unit attached to an external surface of the information processing apparatus with a cover closed, the cover being opened when the plurality of tanks are operated on; and a control unit configured to control the light emission unit, based on the state of the liquid detected by the state detection unit being a predetermined state in one of the plurality of liquid tanks, so that the light emission unit emits light in a light emission pattern corresponding to the one of the plurality of liquid tanks that contains the liquid in the predetermined state, out of a plurality of light emission patterns corresponding to the plurality of liquid tanks, wherein the control unit is configured to control the light emission unit so that the light emission pattern is changed to a different light emission pattern, based on an opening of the cover being detected by the state detection unit during light emission of the light emission unit in the light emission pattern. 
     Further features will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a diagram for illustrating a mode of exterior appearance of an information processing apparatus according to at least one embodiment of the present disclosure. 
         FIG.  2    is a diagram for illustrating an example of a configuration of a status bar. 
         FIG.  3    is a diagram for illustrating an internal configuration of an image forming apparatus illustrated in  FIG.  1   . 
         FIG.  4    is a diagram for illustrating an example of a mode of mounting ink tanks. 
         FIG.  5    is a flow chart for illustrating processing that is executed when a low-ink error occurs. 
         FIG.  6 A ,  FIG.  6 B ,  FIG.  6 C , and  FIG.  6 D  are diagrams for illustrating light emission patterns of white indicator lamps and an orange indicator lamp. 
         FIG.  7    is a diagram for illustrating a light emission pattern that indicates that a printing job is being executed. 
         FIG.  8    is a diagram for illustrating brightnesses at which the white indicator lamps are lit and which are based on the remaining ink amounts. 
         FIG.  9    is a table for showing association between an indicated status and a light emission pattern. 
         FIG.  10 A  and  FIG.  10 B  are diagrams for illustrating light emission patterns that are used when the number of white indicator lamps differs from the number of ink tanks. 
         FIG.  11    is a diagram for illustrating the outline of an internal configuration of the information processing apparatus according to at least one embodiment. 
         FIG.  12    is a diagram for illustrating association that is stored in a table. 
         FIG.  13    is a flow chart for illustrating a notification method to be executed in the information processing apparatus. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     At least one embodiment of the present disclosure is described below with reference to the drawings. 
       FIG.  1    is a diagram for illustrating a mode of exterior appearance of an image forming apparatus, which is an example of an information processing apparatus according to at least one embodiment. An image forming apparatus  100  illustrated in  FIG.  1    includes ink tanks  101 , a carriage  102 , a maintenance cover  103 , a sheet feeding unit  104 , a sheet delivery tray  105 , and a status bar  106 . The image forming apparatus  100  is a single-function printer (SFP), which does not have a reading function (a scanner). The ink tanks  101  are liquid tanks each for storing a liquid to be ejected onto a recording medium. The plurality of detachable ink tanks  101  are attached to the carriage  102 , and the carriage  102  uses a drive force generated by a carriage driving motor (not shown) to reciprocate in the direction of the arrow A of  FIG.  1   . The maintenance cover  103  is an openable cover that enables a user to access the interior of a main body for the purpose of, for example, replacing an ink tank, removing a jammed sheet, and cleaning. The sheet feeding unit  104  is an inlet for placing recording sheets of various sizes. The sheet delivery tray  105  is a tray onto which a recording sheet that has been placed in the sheet feeding unit  104 , conveyed, and finished being printed is to be delivered. The status bar  106  is a light emission unit, which includes a plurality of indicator lamps (light emission members) and is attached to an external surface of the image forming apparatus  100  with the maintenance cover  103  closed. That is, the status bar  106  is attached in a place viewable from the outside of the image forming apparatus  100  irrespective of whether the maintenance cover  103  is open or closed. The status bar  106  notifies the state of the image forming apparatus  100  to the outside through its light emission pattern. The status bar  106  is attached in a place that allows a user to recognize its light emission pattern even when it is difficult for the user to operate the image forming apparatus  100  due to the location of the user. 
       FIG.  2    is a diagram for illustrating an example of a configuration of the status bar  106  illustrated in  FIG.  1   . As illustrated in  FIG.  2   , five white indicator lamps  200  and one orange indicator lamp  201 , which are aligned into a straight line, are attached to the status bar  106  illustrated in  FIG.  1   . The orange indicator lamp  201  is placed at a right end of the status bar  106 . The color in which the orange indicator lamp  201  (a first light emission member) is lit may thus differ from the color in which the rest of light emission members (light emission members other than the first light emission member), namely, the white indicator lamps  200 , are lit. The status bar  106  may be designed so that the orange indicator lamp  201  is lit when the state of the image forming apparatus  100  notified through a light emission pattern has an importance level set in advance. The brightnesses of the white indicator lamps  200  and the orange indicator lamp  201  are changeable. Light emitting elements (for example, LEDs) are used for the white indicator lamps  200  and the orange indicator lamp  201 . The colors in which the indicator lamps emit light are not limited to white and orange. The arrangement of the indicator lamps on the status bar  106  is not limited to the one illustrated in  FIG.  2   . 
       FIG.  3    is a diagram for illustrating an example of an internal configuration of the image forming apparatus  100  illustrated in  FIG.  1   . As illustrated in  FIG.  3   , the image forming apparatus  100  illustrated in  FIG.  1    includes a central processing unit (CPU)  301 , a program memory  303 , a data memory  304 , the status bar  106 , an indicator lamp control circuit  320 , an interface control circuit  307 , a motor control circuit  309 , a conveyance motor  310 , a CR motor  311 , a recovery motor  312 , a head control circuit  313 , a print head  314 , a sensor control circuit  315 , an ink attachment/detachment sensor  316 , a remaining ink amount sensor  317 , a cover sensor  318 , and a carriage sensor  319 . 
     The CPU  301  controls the components via an internal bus  302 . The operation of the CPU  301  in the form of a microprocessor is based on data stored in the program memory  303 , which is in the form of a read-only memory (ROM), and data stored in the data memory  304 , which is in the form of a random access memory (RAM). The data memory  304  includes a work memory  305  to be used when the CPU  301  executes a control program, and an image memory  306  for storing image data to be formed on a recording medium. The CPU  301  controls the interface control circuit  307  to receive printing job data from a host computer  308 , which is connected to the image forming apparatus  100  via an external interface, and to notify the status of the image forming apparatus  100  to the host computer  308 . The motor control circuit  309  controls the driving of the conveyance motor  310 , the CR motor  311 , and the recovery motor  312  based on a control signal from the CPU  301 . The conveyance motor  310  drives sheet feeding rollers, conveyance rollers, and sheet delivery rollers to convey a recording sheet, which is a recording medium, from the sheet feeding unit  104  to the sheet delivery tray  105 . The CR motor  311  is a carriage motor by which the carriage is reciprocally driven. The recovery motor  312  drives a recording head recovery mechanism and controls the mechanism in synchronization with the driving of the carriage, to thereby execute recovery operation for keeping the print head  314  in an appropriate state. The head control circuit  313  controls the print head  314  in synchronization with the reciprocal operation of the carriage, based on a control signal from the CPU  301 . The print head  314  forms an image on a recording sheet, which is a recording medium. The ink attachment/detachment sensor  316  detects that one of the ink tanks  101  has been detached from the carriage  102 , and detects that the ink tank  101  that is compatible with the image forming apparatus  100  has been attached to the carriage  102 . The remaining ink amount sensor  317  detects, for each of the ink tanks  101 , a remaining ink amount, which is the amount of ink remaining in the ink tank. The cover sensor  318  detects that the maintenance cover  103  has been opened or closed. The carriage sensor  319  detects that the carriage  102  has moved. The ink attachment/detachment sensor  316 , the remaining ink amount sensor  317 , the cover sensor  318 , and the carriage sensor  319  each include a mechanical switch. The sensor control circuit  315  notifies detection results from those sensors to the CPU  301 . The indicator lamp control circuit  320  controls, based on a control signal from the CPU  301 , the lengths of time for which the white indicator lamps  200  and orange indicator lamp  201  attached to the status bar  106  are lit, the lengths of time for which the white indicator lamps  200  and the orange indicator lamp  201  are off, and the time interval of blinking, to thereby create a light emission pattern corresponding to the state of the image forming apparatus  100 . 
       FIG.  4    is a diagram for illustrating an example of a mode of mounting the ink tanks  101  to the carriage  102  illustrated in  FIG.  1   . In the example illustrated in  FIG.  4   , the ink tanks  101  of five colors can be attached to the carriage  102 . In this case, as illustrated in  FIG.  4   , the ink tanks  101  are attached in the order of magenta (M), dye black (BK), yellow (Y), pigment black (PGBK), and cyan (C) from the left-hand side of the carriage  102 . 
     Examples of items to be detected/determined by the image forming apparatus  100  as its own running state include a normal state, an error state, a job executing state, and an idle state. When it is determined that the image forming apparatus  100  is in a normal state, for example, the indicator lamp control circuit  320  turns off all of the white indicator lamps  200  and the orange indicator lamp  201 . 
     Indicator lamp control executed when the image forming apparatus  100  is in an error state and the error is a low-ink error (an ink-tank-replacing-required error) is described below. The notification of the low-ink error is an alert for notifying the outside when the remaining ink amount is small in at least one of the ink tanks  101  attached to the carriage  102 , that the ink tank  101  having a small amount of remaining ink requires replacing. The following description takes as an example a case in which, out of the ink tanks  101  of five colors illustrated in  FIG.  4   , the third tank from the left containing yellow (Y) ink is small in remaining ink amount and requires replacing. 
       FIG.  5    is a flow chart for illustrating an example of processing that is executed in the image processing apparatus  100  when a low-ink error occurs. 
     First, when the remaining ink amount sensor  317  detects that the remaining ink amount has become smaller than a predetermined amount (threshold value) in any one of the ink tanks  101 , the sensor control circuit  315  notifies the fact to the CPU  301 . Then, the CPU  301  specifies a light emission pattern corresponding to the notified situation to the indicator lamp control circuit  320 . The indicator lamp control circuit  320  lights the white indicator lamp  200  that corresponds to the ink tank having a remaining ink amount smaller than the predetermined amount and the orange indicator lamp  201  in the light emission pattern specified by the CPU  301  (Step S 500 ). This light emission pattern is a pattern unique to the indication of the low-ink error. Even when it is difficult for the user to operate the image forming apparatus  100 , the user can therefore recognize the fact that the low-ink error has occurred and the ink tank with a small remaining ink amount out of the plurality of ink tanks. 
     The cover sensor  318  subsequently determines whether the maintenance cover  103  is open (Step S 501 ). When determining that the maintenance cover  103  is closed, the cover sensor  318  does not particularly issue a notification, and the indicator lamp control circuit  320  therefore continues the current light emission pattern of the white indicator lamps  200  and the orange indicator lamp  201 . When the cover sensor  318  determines that the maintenance cover  103  is open, on the other hand, the sensor control circuit  315  sends a notification to that effect to the CPU  301 . The CPU  301  specifies a light emission pattern corresponding to the notified maintenance cover open state to the indicator lamp control circuit  320 . The indicator lamp control circuit  320  lights the white indicator lamps  200  and the orange indicator lamp  201  in the light emission pattern specified by the CPU  301  (Step S 502 ). 
     The carriage sensor  319  subsequently determines whether the carriage  102  has moved to a position at which the ink tank can be replaced (Step S 503 ). When determining that the carriage  102  has not moved to the position at which the ink tank can be replaced, the carriage sensor  319  does not particularly issue a notification, and the indicator lamp control circuit  320  therefore continues the current light emission pattern of the white indicator lamps  200  and the orange indicator lamp  201 . When the carriage sensor  319  determines that the carriage  102  has moved to the position at which the ink tank can be replaced, on the other hand, the sensor control circuit  315  sends a notification to that effect to the CPU  301 . The CPU  301  specifies a light emission pattern corresponding to the notified ink tank replacing stand-by state to the indicator lamp control circuit  320 . The indicator lamp control circuit  320  lights the white indicator lamps  200  and the orange indicator lamp  201  in the light emission pattern specified by the CPU  301  (Step S 504 ). 
     The ink attachment/detachment sensor  316  subsequently determines whether the relevant ink tank  101  has been detached from the carriage  102  (Step S 505 ). When determining that the ink tank  101  has not been detached from the carriage  102 , the ink attachment/detachment sensor  316  does not particularly issue a notification, and the indicator lamp control circuit  320  therefore continues the current light emission pattern of the white indicator lamps  200  and the orange indicator lamp  201 . When the ink attachment/detachment sensor  316  determines that the relevant ink tank has been detached from the carriage  102 , on the other hand, the sensor control circuit  315  sends a notification to that effect to the CPU  301 . The CPU  301  specifies a light emission pattern corresponding to the notified ink tank detached state to the indicator lamp control circuit  320 . The indicator lamp control circuit  320  lights the white indicator lamps  200  and the orange indicator lamp  201  in the light emission pattern specified by the CPU  301  (Step S 506 ). 
     The ink attachment/detachment sensor  316  subsequently determines whether the correct ink tank  101  has been attached to the carriage  102  (Step S 507 ). When determining that the correct ink tank  101  has not been attached to the carriage  102 , the ink attachment/detachment sensor  316  does not particularly issue a notification, and the indicator lamp control circuit  320  therefore continues the current light emission pattern of the white indicator lamps  200  and the orange indicator lamp  201 . When the ink attachment/detachment sensor  316  determines that the correct ink tank  101  has been attached to the carriage  102 , on the other hand, the sensor control circuit  315  sends a notification to that effect to the CPU  301 . The CPU  301  specifies to the indicator lamp control circuit  320  a light emission pattern corresponding to the notified state in which the correct ink tank is attached. The indicator lamp control circuit  320  lights the white indicator lamps  200  and the orange indicator lamp  201  in the light emission pattern specified by the CPU  301  (Step S 508 ). 
     The cover sensor  318  subsequently determines whether the maintenance cover  103  is closed (Step S 509 ). When determining that the maintenance cover  103  is not closed, the cover sensor  318  does not particularly issue a notification, and the indicator lamp control circuit  320  therefore continues the current light emission pattern of the white indicator lamps  200  and the orange indicator lamp  201 . When the cover sensor  318  determines that the maintenance cover  103  is closed, on the other hand, the sensor control circuit  315  sends a notification to that effect to the CPU  301 . The CPU  301  specifies a light emission pattern corresponding to the notified maintenance cover closed state to the indicator lamp control circuit  320 . The indicator lamp control circuit  320  lights the white indicator lamps  200  and the orange indicator lamp  201  in the light emission pattern specified by the CPU  301  (Step S 510 ). 
     The light emission patterns of the white indicator lamps  200  and the orange indicator lamp  201  in the processing steps described with reference to  FIG.  5    are described below.  FIG.  6 A  to  FIG.  6 D  are diagrams for illustrating an example of the light emission patterns of the white indicator lamps  200  and the orange indicator lamp  201  in the processing steps described with reference to  FIG.  5   . The example given in  FIG.  6 A  to  FIG.  6 D  has five white indicator lamps  200 . In  FIG.  6 A  to  FIG.  6 D , a lit lamp among the white indicator lamps  200  and the orange indicator lamp  201  is represented by a white graphic with black outline and an unlit lamp among the white indicator lamps  200  and the orange indicator lamp  201  is represented by a black graphic, (the same applies to the rest of the drawings). 
     An example of the light emission pattern indicating the low-ink error in Step S 500  and the light emission pattern indicating the wait for ink tank replacing in Step S 504  is illustrated in  FIG.  6 A . Each of the five white indicator lamps  200  corresponds to one of the ink tanks  101  in five colors on a one-to-one basis. Here, out of the ink tanks  101  attached to the carriage  102  in an arrangement that is illustrated in  FIG.  4   , the magenta (M) ink tank  101 , which is the first from the left, is associated with the first white indicator lamp  200  from the left out of the white indicator lamps  200  attached to the status bar  106 . Out of the ink tanks  101  attached to the carriage  102  in the arrangement that is illustrated in  FIG.  4   , the dye black (BK) ink tank  101 , which is the second from the left, is associated with the second white indicator lamp  200  from the left out of the white indicator lamps  200  attached to the status bar  106 . Out of the ink tanks  101  attached to the carriage  102  in the arrangement that is illustrated in  FIG.  4   , the yellow (Y) ink tank  101 , which is the third from the left, is associated with the third white indicator lamp  200  from the left out of the white indicator lamps  200  attached to the status bar  106 . Out of the ink tanks  101  attached to the carriage  102  in the arrangement that is illustrated in  FIG.  4   , the pigment black (PGBK) ink tank  101 , which is the fourth from the left, is associated with the fourth white indicator lamp  200  from the left out of the white indicator lamps  200  attached to the status bar  106 . Out of the ink tanks  101  attached to the carriage  102  in the arrangement that is illustrated in  FIG.  4   , the cyan (C) ink tank  101 , which is the fifth from the left, is associated with the fifth white indicator lamp  200  from the left out of the white indicator lamps  200  attached to the status bar  106 . When the ink tanks and the lamps are associated in this way and the remaining amount of the yellow (Y) ink, which is the third from the left out of the ink tanks  101  attached to the carriage  102  in the arrangement that is illustrated in  FIG.  4   , becomes smaller than a threshold value that is a replacing requiring value set in advance, the third white indicator lamp  200  from the left, as well as the orange indicator lamp  201  for indicating that an error has occurred, has a light emission pattern in which the lamp blinks, and the other white indicator lamps  200  have a light emission pattern in which the lamps are kept lit. The indicator lamp control circuit  320  thus performs control so that the light emission pattern of the white indicator lamp  200  associated with the ink tank  101  that has a remaining ink amount smaller than the predetermined threshold value and the orange indicator lamp  201  differs from the light emission pattern of the white indicator lamps  200  other than the associated white indicator lamp  200 . With the light emission pattern illustrated in  FIG.  6 A , the type of the ink tank to be replaced and the position of the ink tank on the carriage  102  can be notified to the outside of the image forming apparatus  100 . 
     An example of the light emission pattern indicating the maintenance cover open state in Step S 502  and the light emission pattern indicating the maintenance cover closed state in Step S 510  is illustrated in  FIG.  6 B . In this case, three white indicator lamps  200  that are the third to fifth white indicator lamps  200  from the left slowly blink, and the rest of the white indicator lamps  200  and the orange indicator lamp  201  are off. 
     An example of the light emission pattern for the detachment of the relevant ink tank  101  from the carriage  102  in Step S 506  is illustrated in  FIG.  6 C . The white indicator lamp  200  corresponding to the position of the ink tank  101  that has been detached from the carriage  102  and the orange indicator lamp  201 , which is an error indicating lamp, are turned off and the rest of the white indicator lamps  200  are lit, to thereby notify which ink tank has been detached to the outside of the image forming apparatus  100 . In the light emission pattern illustrated in  FIG.  6 C , the third white indicator lamp  200  from the left and the orange indicator lamp  201  are turned off when the yellow (Y) ink tank, which is the third from the left, out of the ink tanks  101  of five colors attached to the carriage  102  in the arrangement that is illustrated in  FIG.  4   . 
     An example of the light emission pattern for the attachment of the correct ink tank  101  to the carriage  102  in Step S 508  is illustrated in  FIG.  6 D . In this case, the orange indicator lamp  201  is off and the white indicator lamps  200  are all lit. This notifies the outside that the correct ink tank  101  has been attached to the carriage  102 , and that the error has been solved as a result. 
     An example of a light emission pattern for when the image forming apparatus  100  executes a printing job based on job data that is received from the host computer  308  illustrated in  FIG.  3    is described below through an example. 
       FIG.  7    is a diagram for illustrating an example of a light emission pattern that indicates that the image forming apparatus  100  is executing a printing job. When the image forming apparatus  100  receives job data for printing from the host computer  308 , the CPU  301  controls the status bar  106  via the indicator lamp control circuit  320 . Specifically, the CPU  301  instructs the indicator lamp control circuit  320  to set the light emission pattern of the white indicator lamps  200  and the orange indicator lamp  201  to a light emission pattern corresponding to the state of the image forming apparatus  100  that is in the middle of a printing job. The indicator lamp control circuit  320  instructed by the CPU  301  controls the white indicator lamps  200  and the orange indicator lamp  201  so that the lamps are lit in the corresponding light emission pattern. The controlled lamps are lit and turned off as illustrated in  FIG.  7   , in which the first white indicator lamp  200  from the left is lit first while the rest of the white indicator lamps  200  and the orange indicator lamp  201  are turned off, and the white indicator lamp  200  that is lit is switched from one lamp to its immediate right lamp in a predetermined cycle. The image forming apparatus  100  repeats the switching of the lit lamp until the printing job is finished. The switching of the white indicator lamp  200  that is lit makes it seem like the light moves from the left end rightward. When the CPU  301  determines that the printing job is finished, the white indicator lamps  200  and the orange indicator lamp  201  on the status bar  106  are all turned off to return to a normal state. 
     The CPU  301  may further control, via the indicator lamp control circuit  320 , brightnesses at which the white indicator lamps  200  are lit. For example, the CPU  301  may perform control, via the indicator lamp control circuit  320 , so that the white indicator lamps  200  are lit at brightnesses based on the remaining ink amounts in the ink tanks  101 . 
       FIG.  8    is a diagram for illustrating an example of the brightnesses of the lit white indicator lamps  200  that are controlled in accordance with the remaining ink amounts. As in  FIG.  6 A , the five white indicator lamps  200  correspond to the ink tanks  101  of five colors on a one-to-one basis. The association of the five white indicator lamps  200  with the ink tanks  101  of five colors is the same as the association illustrated in  FIG.  6 A . As illustrated in  FIG.  8   , the brightnesses of the white indicator lamps  200  are controlled in accordance with the remaining ink amounts in the ink tanks  101  (in liquid tanks) that are detected by the remaining ink amount sensor  317 . Brightness values indicated in  FIG.  8    are designed so that a large value indicates a high brightness. In short, when the remaining ink amount is larger in one of the ink tanks  101 , control is performed so that the white indicator lamp  200  associated with the ink tank  101  is lit at a higher brightness. 
     The brightness of each lit white indicator lamp  200  is thus changed in accordance with the remaining ink amount in the ink tank  101  that is associated with the lit white indicator lamp  200 . This enables a user to check the remaining amount in each ink tank even when something hinders the user from operating the image forming apparatus  100 . 
     The light emission pattern determination described above, which is executed by the CPU  301 , may use a table in which an indicated status and a light emission pattern are associated with each other in advance. The CPU  301  refers to the table to read a light emission pattern out of the table, with an indicated status as a search key. 
       FIG.  9    is a table for showing an example of the association between an indicated status and a light emission pattern. As shown in  FIG.  9   , an indicated status “power-is-on indication”, for example, is associated with a light emission pattern “lighting of white LEDs shifts from center toward left and right ends”. This means that a light emission pattern used when the image forming apparatus  100  is in a state in which power is switched on and booting is being executed, is a pattern in which the white indicator lamps  200  that are lit are sequentially switched from the white indicator lamps  200  placed at the center to the white indicator lamps  200  placed to the left and right of the lamps at the center. An indicated status “power-is-off indication” is associated with a light emission pattern “lighting of white LEDs shifts from left and right ends toward center”. This means that a light emission pattern used when the image forming apparatus  100  is in a state in which power is switched off and a shutdown procedure is in progress is a pattern in which the white indicator lamps  200  that are lit are sequentially switched from the white indicator lamps  200  placed at the left and right ends to the white indicator lamps  200  placed at the center. 
     In this manner, each indicated status is associated with a light emission pattern on a one-to-one basis in advance, and the indicator lamps are lit in a light emission pattern corresponding to the indicated status. The state of the image forming apparatus can therefore be notified to the outside by the turning on/off of the indicator lamps alone. 
     A light emission pattern used when the number of ink tanks  101  and the number of white indicator lamps  200  differ from each other is described below through two examples.  FIG.  10 A  and  FIG.  10 B  are diagrams for illustrating light emission patterns that may be used when the number of white indicator lamps  200  differs from the number of ink tanks  101 . An example of a light emission pattern for a case in which the number of white indicator lamps  200  is smaller than the number of ink tanks  101  is illustrated in  FIG.  10 A . As illustrated in  FIG.  10 A , the ink tanks  101  of five colors are attached to the carriage  102 , and three white indicator lamps  200  and one orange indicator lamp  201  are attached to the status bar  106 , for example. When the remaining amount of the pigment black (PGBK) ink in the fourth ink tank from the left out of the ink tanks  101  of five colors becomes smaller than the threshold value and requires replacing, the white indicator lamps  200  and orange indicator lamp  201  attached to the status bar  106  are lit/turned off in a light emission pattern corresponding to the ink tank of pigment black (PGBK), to thereby notify which ink tank is to be replaced to the outside of the apparatus. In the example illustrated in  FIG.  10 A , the second and third white indicator lamps  200  from the left and the orange indicator lamp  201  are lit, and the rest of the white indicator lamps  200  are turned off. This notifies the outside of the apparatus that the pigment black (PGBK) ink tank is the ink tank  101  to be replaced. In this manner, a corresponding light emission pattern is determined in advance for each ink tank  101  so that the ink tank  101  that has a remaining ink amount smaller than the threshold value can be recognized, and the turning on/off of the white indicator lamps  200  and the orange indicator lamp  201  is controlled to have a relevant light emission pattern. 
     An example of a light emission pattern for a case in which the number of white indicator lamps  200  is larger than the number of ink tanks  101  is illustrated in  FIG.  10 B . As illustrated in  FIG.  10 B , the ink tanks  101  of five colors are attached to the carriage  102 , and the number of white indicator lamps  200  that are more than the number of ink tanks  101  and one orange indicator lamp  201  are attached to the status bar  106 . In such cases, the white indicator lamps  200  that are attached at a position corresponding to the position of the relevant ink tank  101  and within a range of the width of the relevant ink tank  101  are lit, as well as the orange indicator lamp  201  for indicating an error state, and the rest of the white indicator lamps  200  are all turned off. When the remaining amount of the pigment black (PGBK) ink in the fourth ink tank from the left out of the ink tanks  101  of five colors becomes smaller than the threshold value and requires replacing, the white indicator lamps  200  that are attached within the range of the width of the pigment black (PGBK) ink tank  101  and the orange indicator lamp  201  are lit out of the white indicator lamps  200  attached to the status bar  106 , and the rest of the white indicator lamps  200  are all turned off. This notifies the outside of the apparatus that the pigment black (PGBK) ink tank is the ink tank  101  to be replaced. In this manner, in accordance with the position of each of the ink tanks  101  and the position of each of the white indicator lamps  200 , the turning on/off of the white indicator lamps  200  and the orange indicator lamp  201  is controlled to have a relevant light emission pattern so that the ink tank  101  that has a remaining ink amount smaller than the threshold value can be recognized. 
       FIG.  11    is a diagram for illustrating the outline of an internal configuration of the information processing apparatus according to at least one embodiment. As illustrated in  FIG.  11   , an information processing apparatus  400  according to at least one embodiment includes a state detection unit  410 , a light emission unit  420 , a control unit  430 , liquid tanks  440 , and a table  450 . The state detection unit  410  executes detection processing for detecting the state of the information processing apparatus  400 . The state detection unit  410  corresponds to the components illustrated in  FIG.  3    that detect the state (an operation state, an error state, or the like) of the information processing apparatus  400 , for example, the sensor control circuit  315 , the ink attachment/detachment sensor  316 , the remaining ink amount sensor  317 , the cover sensor  318 , and the carriage sensor  319 . The light emission unit  420  includes a plurality of LEDs or similar light emitting elements, and corresponds to the status bar  106  illustrated in  FIG.  3   . The liquid tanks  440  are a plurality of ink tanks for storing liquids to be ejected onto a recording medium, and one liquid tank  440  is provided for each color. The liquid tanks  440  correspond to the ink tanks  101  illustrated in  FIG.  1   . The control unit  430  controls the light emission pattern of the light emission unit  420 , based on the ink states in the liquid tanks  440  that are detected by the state detection unit  410 . The control unit  430  executes determination processing in which a light emission pattern of the light emission unit  420  is determined based on the ink states in the liquid tanks  440  that are detected by the state detection unit  410 , and executes light emission processing in which the light emission unit  420  is controlled so as to emit light in the determined light emission pattern. Specifically, the control unit  430  controls the light emission unit  420  based on the fact that the state of the liquid detected by the state detection unit  410  is a predetermined state (a state in which the remaining liquid amount is smaller than a threshold value) in one of the plurality of liquid tanks  440 , so that the light emission unit  420  emits light in a light emission pattern corresponding to the liquid tank  440  that contains the liquid in the predetermined state, out of a plurality of light emission patterns corresponding to the plurality of liquid tanks  440 . The control unit  430  corresponds to the CPU  301  and indicator lamp control circuit  320  illustrated in  FIG.  3   . When the state detection unit  410  is designed to detect the state of the information processing apparatus  400  and there are a plurality of states detected by the state detection unit  410 , the control unit  430  may control the light emission pattern of the light emission unit  420  based on a state that is higher in terms of importance level set in advance than the other detected states. The table  450  stores states of liquids contained in the liquid tanks  440  and light emission patterns of the light emission unit  420  in association with each other in advance. 
       FIG.  12    is a diagram for illustrating an example of the association that is stored in the table  450  illustrated in  FIG.  11   . In the table  450  illustrated in  FIG.  11   , states of liquids contained in the liquid tanks  440  and light emission patterns are associated with each other as illustrated in  FIG.  12   . The states of liquids are ink states in the liquid tanks  440  that are detected by the state detection unit  410 . Specifically, the states of liquids contained indicate which liquid tank out of the liquid tanks  440  requires replacing, how much ink remains in which liquid tank, or the like. The light emission pattern is a pattern of turning on/off light in which the control unit  430  controls the light emission unit  420 . The control unit  430  searches the stored association for a light emission pattern by using, as a search key, an ink state that has been detected by the state detection unit  410  in one of the liquid tanks  440 . 
     A notification method to be executed in the information processing apparatus illustrated in  FIG.  11    is described below.  FIG.  13    is a flow chart for illustrating an example of the notification method to be executed in the information processing apparatus  400  illustrated in  FIG.  11   . First, the state detection unit  410  detects ink states in the liquid tanks  440  (Step S 1 ). The control unit  430  determines a light emission pattern for the light emission unit  420  based on the ink states in the liquid tanks  440  that have been detected by the state detection unit  410  (Step S 2 ). The determination involves a search of the table  450  for a light emission pattern by the control unit  430 , with the ink states in the liquid tanks  440  that have been detected by the state detection unit  410  as a search key. The control unit  430  subsequently controls the light emission unit  420  so that light is emitted in the determined light emission pattern (Step S 3 ). 
     In at least one embodiment, the light emission unit attached to an external surface of the information processing apparatus is thus controlled so as to emit light in a determined light emission pattern by detecting ink states in the liquid tanks and by determining a light emission pattern based on the detected ink states. A mechanism for checking indicator lamps through the maintenance cover is therefore not required, which leads to cost reduction. In addition, specific information about an error that has occurred can be obtained without opening the maintenance cover. This accordingly enables a user to recognize, in the event of, for example, a low-ink error, which ink tank requires replacing, the position of that ink tank, and other specifics of the error that has occurred, even when something hinders the user from operating the apparatus. 
     Other Embodiments 
     Embodiment(s) of the present disclosure can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like. 
     While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure 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.