Patent Publication Number: US-11655115-B2

Title: Image recording apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from prior Japanese patent application No. 2020-052680, filed on Mar. 24, 2020, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     Aspects of the present disclosure relate to an image recording apparatus, and in particular, to an image recording apparatus configured to perform overlapping conveyance. 
     BACKGROUND ART 
     Known is an image recording apparatus that, when performing image recording while conveying a plurality of sheet-shaped recording media, performs overlapping conveyance of conveying the recording media by causing a front end portion of a subsequent recording medium to overlap a rear end portion of a preceding recording medium. 
     Related art discloses a configuration where a lever is provided in a conveying path of a recording medium, a detection sensor is provided on a further upstream side than the lever in the conveying direction, and a rear end portion of a preceding recording medium detected by the detection sensor is pressed downward by the lever, thereby causing the rear end portion to overlap a front end portion of a subsequent recording medium. 
     Related art also discloses a configuration where a part of a conveying path configuring a lower side guide surface is arranged in a position higher than a downstream side of the part in a conveying direction and a subsequent recording medium is conveyed in a position higher than a preceding recording medium, thereby causing the recording media to overlap each other. 
     However, according to the configurations disclosed in the related art, a mechanism configured to perform overlapping conveyance becomes complicated. Also, the conveying path becomes large, so that the image recording apparatus is also enlarged. 
     SUMMARY 
     An aspect of the present disclosure provides an image recording apparatus configured to overlap and convey recording media, in which the image recording apparatus is prevented from being enlarged, and in which a mechanism configured to perform overlapping conveyance is suppressed from being complicated. 
     According to an aspect of the present disclosure, there is provided an image recording apparatus including: a recording unit configured to perform recording on a sheet-shaped recording medium; an accommodation part configured to accommodate therein a plurality of recording media and having a support surface on which the plurality of the recording media is supported in a stacked manner, the plurality of the recording media including a first recording medium and a second recording medium, and the first recording medium being stacked on the second recording medium; a conveying path along which the recording medium is conveyed from the accommodation part to the recording unit; a feeder roller pivotally supported so as to contact the recording medium accommodated in the accommodation part from above, the feeder roller being configured to sequentially feed the plurality of recording media in a conveying direction of the recording medium; a reversing path configuring at least a part of the conveying path between the accommodation part and the recording unit, the reversing path being configured to convey the recording medium while reversing front and rear surfaces of the recording medium; a recording medium detection unit located above the support surface and between the feeder roller and a downstream end of the support surface in the conveying direction, the recording medium detection unit being configured to detect the recording medium fed by the feeder roller; and a controller configured to control the feeder roller so as to feed the second recording medium in a manner that a front end portion of the second recording medium overlaps a rear end portion of the first recording medium, the control being performed by the controller when the recording medium detection unit detects the rear end portion of the first recording medium fed by the feeder roller. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic configuration view of an image recording apparatus according to a first embodiment; 
         FIG.  2    is a functional block diagram of the image recording apparatus shown in  FIG.  1   ; 
         FIG.  3    is a graph depicting a temporal change in output value of a recording medium detection unit, and a temporal change in conveying speed of a recording medium; 
         FIG.  4 A  depicts an aspect of conveying a first recording medium of image recording media shown in  FIG.  1   ,  FIG.  4 B  depicts an aspect of the image recording apparatus shown in  FIG.  1    when a recording medium detection unit detects a rear end portion of the first recording medium, and  FIG.  4 C  depicts an aspect of the image recording apparatus shown in  FIG.  1    during overlapping processing; 
         FIG.  5    is a schematic configuration view of an image recording apparatus according to a second embodiment; 
         FIG.  6    is a partial view depicting a configuration of a feeder roller and its periphery of an image recording apparatus according to a third embodiment; 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinbelow, each embodiment will be described with reference to the drawings. 
     First Embodiment 
       FIG.  1    is a schematic configuration view of an image recording apparatus  1  according to a first embodiment.  FIG.  2    is a functional block diagram of the image recording apparatus  1  shown in  FIG.  1   . The image recording apparatus  1  includes an accommodation part  2  and a controller  3 . The accommodation part  2  is configured to accommodate therein a plurality of sheet-shaped recording media  90  and has a support surface  2   a  on which the plurality of recording media  90  is supported in a stacked manner. The recording media  90  includes a first recording medium  90 A and a second recording medium  90 B. The first recording medium  90 A is stacked on the second recording medium  90 B. As described in detail later, while performing a print job on a plurality of recording media  90 , when a recording medium detection unit  8  detects a rear end portion of the first recording medium  90 A fed by a feeder roller  9 , the controller  3  of the image recording apparatus  1  executes overlapping processing of controlling the feeder roller  9  so as to feed the second recording medium  90 B so that a front end portion of the second recording medium  90 B overlaps the rear end portion of the first recording medium  90 A. Thereby, in the print job, a recording operation of recording image data on each of the recording media  90  is efficiently performed. 
     Specifically, as shown in  FIGS.  1  and  2   , the image recording apparatus  1  of the present embodiment includes a housing  14 , a recording unit  4  configured to perform recording on the recording medium  90 , a platen  5  facing the recording unit  4  with a gap in a predetermined direction (for example, an upper and lower direction) and configured to support the recording medium  90  to be recorded by the recording unit  4 , and a conveying path  6  along which the recording medium  90  is conveyed from the accommodation part  2  to the recording unit  4 . The recording unit  4  includes a recording head  19  having ink nozzles for ejecting ink supplied from an outside toward the recording medium  90 , and a carriage  18  on which the recording head  19  is mounted. The platen  5  extends in a horizontal direction, for example. 
     The conveying path  6  is formed to be curved as a whole. The conveying path  6  shown in  FIG.  1    extends, for example, from a downstream end, in a predetermined conveying direction, of the uppermost recording medium  90  (here, the first recording medium  90 A) accommodated in the accommodation part  2  toward the rear and upper side of the image recording apparatus  1  and then extends forward. The conveying path  6  has a reversing path  6   a . The reversing path  6   a  configures at least a part of the conveying path  6  between the accommodation part  2  and the recording unit  4 , and is configured to convey the recording medium  90  while reversing front and rear surfaces of the recording medium  90 . The image recording apparatus  1  includes an outer guide member  50  defining at least a part of an outer periphery side of the reversing path  6   a  viewed in a direction of a rotation axis Y of the feeder roller  9 , and an inner guide member  51  defining at least a part of an inner periphery side of the reversing path  6   a  viewed in the direction of the rotation axis Y of the feeder roller  9 . The inner guide member  51  faces the outer guide member  50  at a position closer to the feeder roller  9  than the outer guide member  50 . 
     The image recording apparatus  1  also includes a feeder roller  9 , conveying rollers  10  and  11 , and discharge rollers  12  and  13 . The feeder roller  9  is pivotally supported so as to contact the recording medium  90  accommodated in the accommodation part  2  from above. The feeder roller  9  is configured to sequentially feed the plurality of recording media  90  in the conveying direction. The conveying rollers  10  and  11  are configured to convey the recording medium  90  fed from the accommodation part  2  along the conveying path  6 . The discharge rollers  12  and  13  are configured to discharge the recording medium  90  having passed through the recording unit  4  to an outside of the housing  14 . The conveying rollers  10  and  11  are arranged in predetermined positions between the feeder roller  9  and the recording unit  4  in the conveying direction. In the image recording apparatus  1 , for example, the conveying rollers  10  and  11  are arranged in positions close to an upstream end of the platen  5 , and the discharge rollers  12  and  13  are arranged in positions close to a downstream end of the platen  5 . 
     The feeder roller  9  is pivotally supported by a swinging member  15  pivotally supported to be swingable around a rotation axis X. The rotation axis X is arranged in a plane parallel to the support surface  2   a . An urging member  17  is arranged to be in contact with the swinging member  15  in the vicinity of the swinging member  15 . The swinging member  15  is configured to urge the feeder roller  9  toward the support surface  2   a  by an urging force of the urging member  17 . Thereby, the feeder roller  9  is always in contact with the recording medium  90  in the accommodation part  2 . 
     The image recording apparatus  1  also includes an inclination part  16  arranged between the accommodation part  2  and the reversing path  6   a  in the conveying direction. The inclination part  16  has an inclined surface  16   a  that is inclined obliquely upward from a downstream end of the accommodation part  2  in the conveying direction toward the reversing path  6   a . The inclination part  16  is configured to guide the recording medium  90  that is conveyed. 
     In the image recording apparatus  1 , for example, at least a part of the feeder roller  9  is arranged to overlap the support surface  2   a  in the direction perpendicular to the support surface  2   a , at least a part of the recording medium detection unit  8  is arranged to overlap the support surface  2   a  in the direction perpendicular to the support surface  2   a  and at least a part of the reversing path  6   a  is arranged to overlap the support surface  2   a  in the direction perpendicular to the support surface  2   a.    
     As shown in  FIG.  2   , the controller  3  includes a CPU  31 , a ROM  32 , a RAM  33 , an EEPROM  34 , and an ASIC  35 . The number of the CPU  31  may be single or plural. In the ROM  32 , a control program for the CPU  31  to execute a predetermined job is stored. In the RAM  33 , a table showing a relation between an output value L1 of the recording medium detection unit  8  and a distance D1, which will be described later, and information about a preset reference value Ds are stored. In the EEPROM  34 , information about diverse initial settings input by a user is stored. 
     The controller  3  includes a first motor driver IC  40  configured to control a feeding motor  41  that is a drive source of the feeder roller  9 , a second motor driver IC  42  configured to drive a conveying motor  43  that is a drive source of the conveying rollers  10  and  11 , a third motor driver IC  44  configured to drive a discharge motor  45  that is a drive source of the discharge rollers  12  and  13 , a fourth motor driver IC  46  configured to drive a carriage motor  46  that is a drive source of the carriage  18 , and a head driver IC  48  configured to operate a piezoelectric element provided to the recording head  19 . The driver ICs  40 ,  42 ,  44 ,  46  and  48  are connected to the ASIC  35 . 
     The CPU  31  is configured to receive an execution request of a print job from the user via an operation unit provided to the housing  14  or an external input unit. The CPU  31  that receives an execution request of a print job is configured to output an execution command of the print job to the ASIC  35 . The ASIC  35  is configured to drive each of the driver ICs  40 ,  42 ,  44 ,  46  and  48  at a predetermined timing, based on the execution command. Thereby, the recording media  90  in the accommodation part  2  are fed in order from the uppermost recording medium by the feeder roller  9 , and are conveyed along the conveying path  6 . The recording medium  90  is conveyed onto the platen  5  by the conveying rollers  10  and  11 , and the recording head  19  reciprocally scans the recording medium  90  in conformity to an operation of the carriage  18 . At this time, the piezoelectric element of the recording head  19  is driven at a predetermined timing, so that ink is ejected from the ink nozzles. As a result, the printing is sequentially performed on the recording medium  90  from an upstream side toward a downstream side in the conveying direction. The recording medium  90  on which the printing is completed is discharged to an outside of the housing  14  by the discharge rollers  12  and  13 . 
     As shown in  FIGS.  1  and  2   , the image recording apparatus  1  further includes the recording medium detection unit  8  located above the support surface  2   a  and between the feeder roller  9  and a downstream end of the support surface  2   a  in the conveying direction. The recording medium detection unit  8  is configured to detect the recording medium  90  fed by the feeder roller  9 . The recording medium detection unit  8  includes a distance measuring sensor configured to detect a distance D1 from the recording medium  90  accommodated in the accommodation part  2  (for example, a distance between the recording medium detection unit  8  and the recording medium  90  in the direction perpendicular to the support surface  2   a ). The distance measuring sensor is, for example, a photo interrupter, and includes a light-emitting unit configured to emit light toward the recording medium  90  and a light-receiving unit configured to receive light from the light-emitting unit reflected on the recording medium  90 . The light-emitting unit and the light-receiving unit are arranged at an end portion (for example, a lower end portion) of the recording medium detection unit  8  on the support surface  2   a  side. In the distance measuring sensor, an output value is changed according to an amount of light received by the light-receiving unit. The output value is larger as the distance D1 is shorter and is smaller as the distance D1 is longer, for example. In the meantime, the type of the distance measuring sensor is not limited thereto. An output of the recording medium detection unit  8  is input to the controller  3 . 
       FIG.  3    is a graph depicting a temporal change in output value L1 of the recording medium detection unit  8  and a temporal change in conveying speed L2 of the recording medium  90 . As shown in  FIG.  3   , when the plurality of recording media  90  in the accommodation part  2  is fed by the feeder roller  9 , the conveying speed L2 changes, for example, periodically. While the recording medium detection unit  8  detects the same recording medium  90  (from time t0 to time t1), the recording medium detection unit  8  detects that the output value L1 is within a reference range (L1≥LT) and the distance D1 is within a preset reference value Ds. Thereafter, when the recording medium  90  deviates from a detection range of the recording medium detection unit  8 , the recording medium detection unit  8  detects that the output value L1 is outside of the reference range (L1&lt;LT) and the distance D1 has changed to become larger than the reference value Ds (from time t1 to time t2). Also, after time t2, the recording medium detection unit  8  detects that the output value L1 has changed over time similarly to the time period from time t0 to t1 and the distance D1 is again within the reference value Ds. 
     In this way, the change of the distance D1 is detected by the recording medium detection unit  8 , so that the recording medium detection unit  8  can detect the rear end portion of each of the recording media  90  fed by the feeder roller  9 . In the meantime, in order to accurately detect the change of the distance D1 by the recording medium detection unit  8 , the recording medium detection unit  8  is preferably arranged to be close to the feeder roller  9  and the recording medium  90  in the accommodation part  2  (for example, a distance between the recording medium detection unit  8  and the feeder roller  9  and a distance between the recording medium detection unit  8  and the recording medium  90  are both several millimeters) on a further downstream side than the feeder roller  9  in the conveying direction. 
     In the image recording apparatus  1  configured as described above, when performing a print job on the plurality of recording media  90 , the above-described processes are sequentially performed on each of the recording media  90 , and the controller  3  executes the following overlapping processing.  FIG.  4 A  depicts an aspect of conveying the first recording medium  90 A of the image recording media shown in  FIG.  1   .  FIG.  4 B  depicts an aspect of the image recording apparatus shown in  FIG.  1    when the recording medium detection unit  8  detects a rear end portion of the first recording medium  90 A.  FIG.  4 C  depicts an aspect of the image recording apparatus shown in  FIG.  1    during overlapping processing. In  FIGS.  4 A to  4 C , only a part of the image recording apparatus  1  is shown, and an outline of an internal structure of the image recording apparatus  1  defining the conveying path  6  is shown with a broken line. 
     When the plurality of recording media  90  is conveyed along the conveying path  6 , the uppermost first recording medium  90 A accommodated in the accommodation part  2  overlaps the recording medium detection unit  8  in the direction perpendicular to the support surface  2   a  and is positioned within the detection range of the recording medium detection unit  8 . By rotation drive of the feeder roller  9 A, a front end portion (an end portion on a side close to the conveying path  6 ) of the first recording medium  90 A in the conveying direction first comes into contact with the inclined surface  16   a  and the outer guide member  50 , and the first recording medium  90 A is guided into the conveying path  6 . The front end portion of the first recording medium  90 A in the conveying direction is nipped between the conveying rollers  10  and  11 , so that the first recording medium  90 A passes through the reversing path  6   a  while contacting the inner guide member  51  ( FIG.  4 A ). Then, a rear end portion of the first recording medium  90 A (a downstream end portion in the conveying direction) is spaced from the feeder roller  9 , and the first recording medium  90 A deviates from the detection range of the recording medium detection unit  8 . 
     At this time, as shown in  FIG.  3   , the output value L1 of the recording medium detection unit  8  is within the reference range (L1≥LT) while the first recording medium  90 A is positioned within the detection range of the recording medium detection unit  8  (from time t0 to time t1 in  FIG.  3   ), but changes to become outside of the reference range when the first recording medium  90 A deviates from the detection range (from time t1 to time t2 in  FIG.  3   ;  FIG.  4 B ). At this time, the rear end portion of the first recording medium  90 A fed by the feeder roller  9  is detected by the recording medium detection unit  8 . The controller  3  refers to the table stored in the RAM  33  to perceive the distance D1 corresponding to the output value L1 of the recording medium detection unit  8 , and determines that the distance D1 has become larger than the reference value Ds when the output value L1 becomes outside of the reference range. Here, in the image recording apparatus  1 , since the reversing path  6   a  configured to reverse the front and rear surfaces of the recording medium  90  is arranged between the accommodation part  2  and the recording unit  4 , the rear end portion of the first recording medium  90 A passing through the reversing path  6   a  is bent toward the support surface  2   a . That is, the rear end portion of the first recording medium  90 A is more floated upward from the second recording medium  90 B at a front side part in the conveying direction than at a rear side part. Therefore, when the first recording medium  90 A passing through the reversing path  6   a  is spaced from the feeder roller  9 , the rear end portion of the first recording medium  90 A is spaced from the recording medium detection unit  8  in a direction in which the distance D1 increases. Thereby, since the change of the distance D1 increases before and after the first recording medium  90 A is spaced from the feeder roller  9 , the recording medium detection unit  8  can appropriately detect the rear end portion of the first recording medium  90 A based on the change of the distance D1. 
     Thereafter, the controller  3  executes overlapping processing of controlling the feeder roller  9  so as to feed the second recording medium  90 B in a manner that a front end portion of the second recording medium  90 B overlaps the rear end portion of the first recording medium  90 A ( FIG.  4 C ). The front end portion of the second recording medium  90 B is guided by the inclined surface  16   a  of the inclination part  16 , so as to overlap the rear end portion of the first recording medium  90 A. In the overlapping processing, the front end portion of the second recording medium  90 B is overlapped on a recording surface-side of the rear end portion of the first recording medium  90 A. In this way, the controller  3  of the present embodiment controls the feeder roller  9  so as to feed the second recording medium  90 B in a case where the distance D1 detected by the recording medium detection unit  8  exceeds the reference value Ds after the feeder roller  9  has started to feed the first recording medium  90 A. 
     As described above, the controller  3  of the image recording apparatus  1  executes the overlapping processing by using the feeder roller  9  in contact with the recording medium  90  accommodated in the accommodation part  2  and the recording medium detection unit  8  configured to detect the recording medium  90  that is fed by the feeder roller  9 . For this reason, the feeder roller  9  and the recording medium detection unit  8  can be arranged to overlap each other in the direction perpendicular to the support surface  2   a  of the accommodation part  2 , for example. Thereby, it is possible to prevent the image recording apparatus  1  from being enlarged toward an outer side of the support surface  2  in a planar view in order to perform overlapping conveyance of the recording media  90 . 
     Further, the controller  3  performs the overlapping processing based on the detection result of the recording medium detection unit  8  for each recording medium  90  immediately after conveyed from the accommodation part  2 . Therefore, it is possible to suppress the conveying path  6  from being complicated in order to perform the overlapping processing. Thereby, it is possible to suppress a mechanism configured to perform overlapping conveyance from being complicated. 
     The recording medium detection unit  8  controls the feeder roller  9  so as to feed the second recording medium  90 B in a case where the distance D1 exceeds the reference value Ds. Thereby, it is possible to control the feeder roller  9  so as to feed the second recording medium  90 B based on the change of the distance D1. Therefore, it is possible to implement the overlapping processing with a relatively simple structure. 
     The recording medium detection unit  8  includes the photo interrupter. Thereby, it is possible to implement the recording medium detection unit  8  that is relatively inexpensive and has highly accurate detection performance. 
     Hereinafter, a modified embodiment of the first embodiment is described. In an image recording apparatus of the present modified embodiment, the recording medium detection unit  8  includes an ultrasonic sensor. The ultrasonic sensor is, for example, a high frequency-type ultrasonic sensor. Examples of the commercially available ultrasonic sensor include “MA300D1-1” made by Murata Manufacturing Co., Ltd. According to this ultrasonic sensor, ultrasonic waves are emitted toward the recording medium  90  and reflected waves of the emitted ultrasonic waves are received, so that it is possible to achieve the effects, which are similar to the case where the photo interrupter is used, based on a received state of the reflected waves. Hereinafter, other embodiments are described focusing on differences from the first embodiment. 
     Second Embodiment 
       FIG.  5    is a schematic configuration view of an image recording apparatus  101  according to a second embodiment. The image recording apparatus  101  further includes a tip end detection unit  20  arranged on the conveying path  6  between the accommodation part  2  and the conveying rollers  10  and  11 . The tip end detection unit  20  is configured to detect a tip end portion of the recording medium  90  that is conveyed. Here, the tip end detection unit  20  is arranged between the accommodation part  2  and the reversing path  6   a  in the conveying direction and is configured to detect the recording medium  90  passing through the inclination part  16 . The tip end detection unit  20  is fixed to an inner side of the housing  14  exposed to the conveying path  6 , for example. 
     The tip end detection unit  20  is, for example, a photo interrupter. The type of the tip end detection unit  20  is not limited thereto. The tip end detection unit  20  may also be a roller that rotates when coming into contact with the tip end portion of the recording medium  90  and a power generation device that generates power by rotation of the roller, for example. The tip end detection unit  20  may have a contact part arranged to contact the tip end portion of the recording medium  90  and an output part connected to the contact part and whose output changes before and after the contact between the contact part and the recording medium  90 , for example. Examples of the contact part include a lever arranged so that a position thereof can change by coming into contact with the tip end portion of the recording medium  90 , and examples of the output part include a switch element that is turned on or off by a position of the lever. 
     In the overlapping processing, the controller  3  executes standby processing of causing the second recording medium  90 B to stand by in a state where the front end portion of the second recording medium  90 B is located in a predetermined standby position WP on an upstream side of the conveying rollers  10  and  11  in the conveying direction, when the tip end detection unit  20  detects the front end portion of the second recording medium  90 B. In the overlapping processing, the controller  3  also executes re-conveying processing of resuming conveyance of the second recording medium  90 B in a manner that the front end portion of the second recording medium  90 B overlaps the rear end portion of the first recording medium  90 A in conformity to a size of a margin of the rear end portion of the first recording medium  90 A recorded by the recording unit  4 . Here, the controller  3  can perceive the size of the margin of the rear end portion of the first recording medium  90 A by an amount of image data that is to be printed on the first recording medium  90 A by the recording unit  4 , for example. The standby processing and the re-conveying processing can be implemented by the controller  3  controlling the motor driver ICs  40  and  42  so as to drive at least one of the feeder roller  9  and the conveying roller  10  at a predetermined timing. 
     According to the image recording apparatus  101 , since the tip end portion of the second recording medium  90 B can be detected by the tip end detection unit  20 , it is easy to overlap the tip end portion of the second recording medium  90 B on a correct position of the rear end portion of the first recording medium  90 A. Also, the controller  3  executes the standby processing and the re-conveying processing, so that it is possible to individually adjust an overlapping amount between the first recording medium  90 A and the second recording medium  90 B according to an amount of image data that is to be printed on the first recording medium  90 A. Therefore, while preventing the overlapping conveyance mechanism from being complicated, it is possible to perform the overlapping conveyance further efficiently. 
     Since the tip end detection unit  20  is arranged between the accommodation part  2  and the reversing path  6   a  in the conveying direction and is configured to detect the recording medium  90  passing through the inclination part  16 , for example, it is possible to accurately detect the tip end portion of the recording medium  90  by the tip end detection unit  20  while preventing the unnecessary double feeding of the recording media  90  by bringing the recording medium  90  into contact with the inclined surface  16   a  of the inclination part  16 . 
     According to the image recording apparatus  101 , for example, a shortest distance D2 between the tip end detection unit  20  and the inner guide member  51  is larger than a shortest distance D3 between the tip end detection unit  20  and the outer guide member  50 . Here, when the first recording medium  90 A passes through the reversing path  6   a , the tip end portion thereof is nipped between the conveying rollers  10  and  11 , so that the first recording medium is likely to contact the inner guide member  51 . In contrast, the second recording medium  90 B is likely to contact the outer guide member  50  in an early stage of passing through the reversing path  6   a . Therefore, the shortest distances D2 and D3 are set as described above, so that the tip end portion of the second recording medium  90 B can be more easily detected than the tip end portion of the first recording medium  90 A by the tip end detection unit  20 . Thereby, for example, even in a case where the two recording media  90  are double fed, the tip end portion of the second recording medium  90 B can be accurately detected by the tip end detection unit  20 . 
     Third Embodiment 
       FIG.  6    is a partial view depicting a configuration of the feeder roller  9  and its periphery of an image recording apparatus  201  according to a third embodiment. The image recording apparatus  201  includes a support part  25  supporting both the feeder roller  9  and the recording medium detection unit  8 . The support part  25  is pivotally supported to be swingable together with the feeder roller  9  in a plane perpendicular to the rotation axis X. The recording medium detection unit  8  is supported by the support part  25  so that a posture of the recording medium detection unit  8  in a direction perpendicular to the support surface  2   a  is maintained during the swinging of the feeder roller  9 . Thereby, in the present embodiment, the lower end portion of the recording medium detection unit  8  faces downward in the vertical direction all the time during the swinging of the feeder roller  9 . The support part  25  is connected to the swinging member  15 . 
     For example, the support part  25  of the present embodiment has a long hole  25   a  extending in the conveying direction, when viewed in the direction of the rotation axis Y of the feeder roller  9 . The recording medium detection unit  8  has a shaft part  8   a  that is arranged in the long hole  25   a  so as to be reciprocally moveable in a longitudinal direction of the long hole  25   a  and is supported by a peripheral edge of the long hole  25   a . The shaft part  8   a  extends in the direction of the rotation axis Y. 
     A guide member  26  that is opened toward the support surface  2   a  is provided to the recording medium detection unit  8  on an opposite side of the support surface  2   a . An end portion  8   b  of the recording medium detection unit  8  on an opposite side of the support surface  2   a  is inserted in the guide member  26  from the opening of the guide member  26 , and is supported by the guide member  26  so as to be reciprocally moveable in the direction perpendicular to the support surface  2   a . The guide member  26  is positioned by being fixed to a fixing part  27  provided inside of the housing  14 . 
     According to the image recording apparatus  201 , the support part  25  causes the recording medium detection unit  8  to reciprocally move in the direction perpendicular to the support surface  2   a  via the peripheral edge of the long hole  25   a , following the swinging operation of the swinging member  15  around the rotation axis X. At this time, the recording medium detection unit  8  is guided in the direction perpendicular to the support surface  2   a  by the guide member  26 . As a result, a posture of the recording medium detection unit  8  in the direction perpendicular to the support surface  2   a  is maintained during the swinging of the feeder roller  9 . Thereby, even when the plurality of recording media  90  in the accommodation part  2  is sequentially fed by the feeder roller  9  and a stacked amount of the plurality of recording media  90  supported on the support surface  2   a  decreases, the distance D1 in the direction perpendicular to the support surface  2   a  between the uppermost recording medium  90  of the recording media  90  supported on the support surface  2   a  and the recording medium detection unit  8  is maintained substantially constant. Therefore, it is possible to stably detect the rear end portion of the first recording medium  90 A fed by the feeder roller  9  by the recording medium detection unit  8 , irrespective of the stacked amount of the plurality of recording media  90  supported on the support surface  2   a.    
     The present disclosure is not limited to the embodiments, and the configuration and method of the present disclosure can be changed, added or deleted without departing from the spirit of the present disclosure. The recording medium  90  may be paper, or a sheet made of a material (for example, resin or metal) other than paper. The motors  41 ,  43  and  45  may not be individually provided, and one of the motors may also serve as any of the other motors. 
     As described above, an aspect of the present disclosure achieves the effects of preventing the image recording apparatus configured to perform overlapping conveyance from being enlarged and to suppress the mechanism configured to perform overlapping conveyance from being complicated. Therefore, it is useful to widely apply the present disclosure to image recording apparatuses capable of achieving the effects.