JP2013075764A - Image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image recorder for dispensing with an exclusive sensor for detecting a position of a flap for switching a carrying destination of a sheet.SOLUTION: This image recorder includes: a carrying passage 65 for guiding a recording paper sheet 16; a recording portion 24 for recording an image on the recording paper sheet 16; a reversal carrying passage 67 connected to the carrying passage 65 on the upstream side and the downstream side of the recording portion 24; the flap 41 for changing to an attitude for guiding the recording paper sheet 16 to the carrying passage 65 and an attitude for guiding to the reversal carrying passage 67; a sensor 110 arranged in the recording portion 24 and detecting the existence of the recording paper sheet 16 on the carrying passage 65 based on the reflected light relative to the irradiation light to the carrying passage 65; a detected portion 73 which changes its attitude between an attitude in which a well reflecting surface of the irradiation light is opposed to the sensor 110 and an attitude in which a hardly reflecting surface is opposed to the sensor 110; an interlocking portion 74 for changing the attitude of the detected portion 73 by interlocking with change of attitude of the flap 41; and a determining section for determining the attitude of the flap 41 based on the reflected light of the light irradiated to the detected portion 73 from the sensor 110.

Description

  The present invention relates to an image recording apparatus that records an image on a sheet, and more particularly to an image recording apparatus capable of recording an image on both sides of a sheet.

  2. Description of the Related Art Conventionally, an image recording apparatus that can record images on both sides of a sheet is known. In such an image recording apparatus, a refeed conveyance path is formed in addition to a main conveyance path for conveying a sheet from a tray on which the sheet is placed to a discharge port through a recording unit that records an image on the sheet. ing. The re-feed conveyance path is a conveyance path that conveys the sheet whose surface has been recorded by the recording unit and conveyed to the downstream side of the recording unit to the upstream side of the recording unit in the main conveyance path again. The sheet conveyed through the refeed conveyance path reaches the recording unit with the back surface facing the recording unit. Thereby, the recording unit can record an image on the back surface of the sheet.

  In the image recording apparatus as described above, a sheet that is image-recorded only on the front surface and not image-recorded on the back surface needs to be conveyed to the refeed conveyance path. On the other hand, the sheet on which the front and back image recording has been completed needs to be conveyed to the discharge port instead of the refeed conveyance path and discharged from the apparatus. That is, in the image recording apparatus as described above, it is necessary to provide a path switching unit for switching the sheet conveyance destination after image recording. The path switching unit switches the sheet conveyance destination by changing the posture.

  Patent Document 1 discloses a paper refeed device including a switching claw 35 corresponding to the above path switching unit. Patent Document 2 discloses an image forming apparatus including an inversion gate 38 corresponding to the path switching unit.

Japanese Patent Laid-Open No. 5-77996 JP 2005-41635 A

  Since the path switching unit changes its attitude, the image recording apparatus is often provided with a sensor for detecting the attitude of the path switching unit. For example, the re-feeding device disclosed in Patent Document 1 includes an arm 36 attached to the switching claw 35 and a photo interrupter 38 into which the arm 36 can freely intervene in order to detect the position of the switching claw 35. Yes. The position of the switching claw 35 is detected by the photo interrupter 38 detecting the presence or absence of the intervention of the arm 36. In the image forming apparatus disclosed in Patent Document 2, a detection unit 50 capable of detecting the position of the inversion gate 38 is provided.

  However, as described above, when a dedicated sensor for detecting the position of the path switching unit is provided, the number of sensors provided in the image recording apparatus increases. As a result, the cost of the image recording apparatus increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to perform image recording that does not require a dedicated sensor to detect the position of a path switching unit that switches the sheet conveyance destination after image recording. To provide an apparatus.

  (1) An image recording apparatus of the present invention includes a first conveyance path that guides a sheet in a conveyance direction, a support portion that supports the sheet guided along the first conveyance path from below, and an upper portion of the support portion. A recording unit that is provided to face the support unit and that records an image on a sheet supported by the support unit while moving in a direction orthogonal to the conveyance direction, and extends below the support unit. And a first conveyance path at a first position downstream of the recording unit in the conveyance direction and a second position upstream of the recording unit in the conveyance direction. A second conveyance path connected to the first conveyance path, and a lower guide surface of the first conveyance path along the upper surface. A first posture for guiding the sheet and closing the first conveyance path A lower surface constitutes an upper guide surface of the second conveyance path, a flap that rotates to a second posture that guides the sheet along the lower surface, and a light emitting unit that is provided in the recording unit and emits light And a sensor that receives reflected light of the light emitted by the light emitting unit, outputs a signal based on a detection result by the light emitting unit and the light receiving unit, and a recording unit that has moved to a third position. A third posture in which the first surface faces the sensor in the third position, and a fourth posture in which the first surface does not face the sensor in the third position. In response to the detected portion that changes its posture and the posture change of the flap to the first posture, the detected portion is changed to one of the third posture and the fourth posture, and the flap In conjunction with the posture change to the second posture , The interlocking unit that changes the detected portion to the other of the third posture and the fourth posture, and the recording unit is moved to the third position to control the sensor, and is output by the sensor And a determination unit that determines the posture of the flap based on the signal.

  In this configuration, the recording unit is provided to face the support unit. Therefore, the sensor provided in the recording unit is also provided facing the support unit. Therefore, the sensor can be used to detect whether or not the sheet is supported by the support portion. For example, when the size of the reflected light of the light emitted toward the support unit by the light emitting unit is larger than a preset threshold value, it is detected that the sheet is supported by the support unit, and the size of the reflected light is detected. Is less than the above threshold value, it is detected that the sheet is not supported by the support portion.

  Further, in this configuration, the detected portion changes its posture in conjunction with the change in the posture of the flap. Specifically, the detected part changes its posture between a posture in which the first surface faces the sensor and a posture in which the first surface does not face the sensor. And in this structure, a judgment part controls a sensor by making a sensor and a to-be-detected part oppose. And a judgment part judges the attitude | position of a flap based on the signal used as a value which changes with whether the sensor is facing the 1st surface.

  That is, in this configuration, in order to detect the posture of the flap, a sensor for detecting whether or not the sheet is supported by the support portion can be used.

  (2) The detected part has a second surface having a reflectance different from that of the first surface, and the second surface faces the sensor at the third position in the fourth posture.

  According to this structure, the light irradiated from the light emission part reflects on the 1st surface and the 2nd surface. That is, the first surface and the second surface are light reflecting surfaces. Therefore, in the present configuration, the distance between the sensor and the light reflecting surface can be made equal by setting the first surface and the second surface to the same height. As a result, the detection accuracy of the sensor can be improved.

  (3) The support part, the flap, the detected part, and the interlocking part constitute one module. The support part, the flap, the detected part, and the interlocking part are supported only by members constituting the module.

  According to this configuration, since the support portion, the flap, the detected portion, and the interlocking portion constitute one module, when assembling each of the above members constituting the module into the image recording apparatus, each member is individually There is no need to assemble. That is, the support part, the flap, the detected part, and the interlocking part can be easily assembled to the image recording apparatus.

  (4) In the image recording apparatus of the present invention, the first guide member that supports the support portion and forms at least a part of the lower guide surface of the first transport path, and the first guide member are the above A second guide member that is assembled to the first guide member so as to face the opposite side of the recording head and constitutes at least a part of the upper guide surface of the second transport path. The flap is attached to the first guide member or the second guide member. The detected part and the interlocking part are disposed between the first guide member and the second guide member. The first guide member has an opening that exposes the detected portion at a position facing the sensor at the third position.

  According to this configuration, the configuration (3) can be specifically realized.

  (5) The arrangement position of the detected portion in the direction orthogonal to the conveyance direction is a case where a sheet of a fixed size preset as a size for recording an image by the recording unit is supported by the support unit. It is a position other than the edge portion in the direction orthogonal to the conveying direction of the standard size sheet.

  When so-called borderless printing is performed, a recording material such as ink adhered to the sheet by the recording unit remains on the edge of the sheet to be printed, that is, on the support portion in the vicinity of the edge of the sheet. If the remaining recording material adheres to the first surface and the second surface of the detected portion, there is a possibility that an error may occur in the detection result by the sensor. However, according to this structure, the to-be-detected part is arrange | positioned in positions other than the said edge part. Therefore, according to this configuration, it is possible to reduce the possibility that the recording material adheres to the detected portion.

  (6) The fourth position facing the support portion where the recording unit moves to determine whether or not the sheet is supported by the support portion is the third position in a direction orthogonal to the transport direction. The position is different from the position.

  According to this configuration, the position of the recording unit when determining the flap posture is different from the position of the recording unit when determining whether or not the sheet is supported by the support unit. This makes it possible to judge the flap posture by irradiating the sheet supported by the support part, or to judge the presence or absence of support by the sheet support part by irradiating the detected part with light. It is possible to prevent making a judgment.

  (7) The image recording apparatus of the present invention is provided with a biasing member that biases the flap toward the second posture side and a downstream side in the transport direction from the first position, and holds the sheet. A conveying unit that conveys the sheet in the conveying direction and a reverse conveying direction opposite to the conveying direction, a first driving force that conveys the sheet in the conveying direction to the conveying unit, and a sheet that is conveyed in the reverse conveying direction. A driving source for applying a second driving force, the driving source applying the first driving force to the transport unit, and the posture of the flap from the first posture to the second posture. A transport control unit that controls the drive source to apply the second driving force to the transport unit on the condition that the determination is made by the determination unit;

  When the flap supports the sheet on its upper surface, the flap takes the first posture due to its own weight. When the flap does not support the seat, the flap is biased by the biasing member and takes the second posture. That is, the flap takes the first posture when the sheet is supported on the upper surface thereof, and changes its posture from the first posture to the second posture when the sheet passes the flap. According to this configuration, at this time, the conveyance control unit reverses the driving of the conveyance unit, and the sheet is fed backward. As a result, the sheet can be guided to the second conveyance path.

  (8) The interlocking portion is connected to one end of the detected portion and the connecting portion connecting the flap and the other end of the detected portion, and biases the detected portion toward the other end. And a second urging member for changing the posture to the fourth posture. The flap is urged by the second urging member via the detected part and changed in posture to the second posture. The detected portion is moved from the fourth position to the third position against the urging force of the second urging member by changing the position of the flap from the second position to the first position. Changed.

  According to this configuration, the interlocking unit can be specifically realized.

  (9) The image recording apparatus of the present invention further includes a sheet detection unit that detects that the trailing end of the sheet in the conveyance direction is conveyed to a predetermined position upstream of the position in the conveyance direction relative to the position where the sheet passes through the flap. . The determination unit moves the recording unit to the third position on the condition that the sheet detection unit detects that the trailing end of the sheet in the conveyance direction has been conveyed to the predetermined position.

  When images are recorded on both sides of a sheet, the flap needs to be changed in posture from the first posture to the second posture after the trailing end in the sheet transport direction passes the flap. This is because the sheet is conveyed from the first conveyance path to the second conveyance path, and then conveyed again through the first conveyance path to reach the recording unit in a state where an image can be recorded on the back surface. According to this configuration, the determination unit moves the recording unit to the third position slightly before the trailing end in the sheet conveyance direction passes the flap. Thereby, the determination part can detect the attitude | position change of a flap reliably.

  According to the present invention, in order to detect the posture of the flap, it is possible to use a sensor for detecting whether or not the sheet is supported by the support portion. That is, according to the present invention, it is not necessary to provide a dedicated sensor for detecting the posture of the flap.

FIG. 1 is an external perspective view of the multifunction machine 10. FIG. 2 is a longitudinal sectional view schematically showing the internal structure of the printer unit 11, and shows a state where the flap 41 is in the second posture. FIG. 3 is a longitudinal sectional view schematically showing the internal structure of the printer unit 11, and shows a state where the flap 41 is in the first posture. FIG. 4 is an external perspective view of the recording unit 24, the first guide member 71, the platen 42, and the flap 41. FIG. 5 is an external perspective view of the recording unit 24, the flap 41, and the detected unit 73. FIG. 6 is a block diagram showing a configuration of the microcomputer 130. FIG. 7 is a longitudinal sectional view schematically showing the internal structure of the printer unit 11 in a modified example, and shows a state where the flap 41 is in the second posture. FIG. 8 is a vertical cross-sectional view schematically showing the internal structure of the printer unit 11 in a modified example, in which the flap 41 is in the first posture. FIG. 9 is a longitudinal sectional view schematically showing the structure of the module 51. Flowchart for explaining the posture change of the flap 41 and the reversing process of the second transport motor 45

  Hereinafter, embodiments of the present invention will be described. The embodiment described below is merely an example of the present invention, and it is needless to say that the embodiment of the present invention can be changed as appropriate without departing from the gist of the present invention. Further, in the following description, the advance from the starting point of the arrow to the ending point is expressed as the direction, and the traffic on the line connecting the starting point and the ending point of the arrow is expressed as the direction. In the following description, the vertical direction 7 is defined with reference to the state in which the multifunction machine 10 is installed (the state in FIG. 1), and the side where the opening 13 is provided is the front side (front side). A direction 8 is defined, and a left-right direction 9 is defined when the multifunction machine 10 is viewed from the front side (front).

[Overall configuration of MFP 10]
As shown in FIG. 1, the multifunction machine 10 is generally formed in a thin rectangular parallelepiped. The multifunction machine 10 has various functions such as a facsimile function and a print function. The print function has a double-sided image recording function for recording images on both sides of the recording paper. The presence or absence of functions other than the print function is arbitrary. In addition, a printer unit 11 that records an image on a recording sheet 16 (see FIG. 2, an example of a sheet of the present invention) is provided at the lower part of the multifunction machine 10. The printer unit 11 has a housing 14 with an opening 13 formed in the front, and a paper feed tray 20 (see FIG. 2) on which recording paper 16 of various sizes can be placed is inserted and removed in the front-rear direction 8 from the opening 13. Is possible.

  As shown in FIG. 2, the printer unit 11 is provided above the paper feed tray 20 and a paper feed unit 15 that picks up and feeds the recording paper 16 from the paper feed tray 20. A recording unit 24 (an example of the recording unit of the present invention) of an ink jet recording system that discharges ink droplets onto the recording paper 16 fed by the recording medium and records an image on the recording paper 16, and a flap 41 (an example of the flap of the present invention). ) Etc. The paper feeding unit 15, the recording unit 24, and the flap 41 will be described later. The recording unit 24 is not limited to the ink jet system, and various recording systems such as an electrophotographic system can be applied.

[Paper Feeder 15]
As shown in FIG. 2, the paper feed unit 15 is provided on the upper side of the paper feed tray 20. The paper feed unit 15 includes a paper feed roller 25, a paper feed arm 26, and a drive transmission mechanism (not shown). The paper feed roller 25 is pivotally supported at the front end portion of the paper feed arm 26. The paper feed arm 26 rotates about the shaft 28 in the direction of the arrow 29. As a result, the paper feed roller 25 can contact and separate from the paper feed tray 20. The sheet feeding roller 25 is rotated by the driving force of the sheet feeding motor 101 (see FIG. 6) being transmitted by a drive transmission mechanism provided inside the sheet feeding arm 26 and meshing a plurality of gears. The paper feed roller 25 separates the recording papers 16 stacked on the paper feed tray 20 one by one and supplies them to a curved path 65A described below.

[Conveyance path 65]
As shown in FIG. 2, inside the printer unit 11, there is a conveyance path 65 (first end of the present invention) from the front end (back end) of the paper feed tray 20 to the paper discharge tray 21 through the recording unit 24. An example of a conveyance path) is formed. The conveyance path 65 is divided into a curved path 65A and a straight path 65B.

  The curved path 65 </ b> A is a curved path extending from the vicinity of the upper end of the separation inclined plate 22 provided in the paper feed tray 20 to the conveying roller pair 70. The curved path 65 </ b> A is generally formed in an arc shape centering on the inside of the printer unit 11. The recording paper 16 fed from the paper feed tray 20 is transported along the curved path 65 </ b> A and guided to the transport roller pair 70. The curved path 65A is partitioned by an outer guide member 18 and an inner guide member 19 that face each other with a predetermined interval.

  The straight path 65 </ b> B is a straight path that extends from the pair of conveying rollers 70 to the paper discharge tray 21. The straight path 65B is formed by a recording unit 24 and a platen 42 (an example of a support unit according to the present invention), which will be described later, facing each other at a predetermined interval at a location where the recording unit 24 is provided. The recording unit 24 is disposed on the upper side of the straight path 65B, and the platen 42 is disposed on the lower side of the straight path 65B. Further, the straight path 65B is partitioned by an upper guide member 82, which will be described below, and a first guide member 71, which will be described later, at locations where the recording unit 24 is not provided, and facing each other with a predetermined interval.

  The upper guide member 82 is provided above the straight path 65B. Further, as indicated by a broken line in FIG. 2, a recess 83 is formed at a position on the lower surface of the upper guide member 82 and facing the flap 41. The recess 83 is provided at a position different from the spur 63 described later in the left-right direction 9. Further, as will be described later, the flap 41 rotates, and the portion of the rotating tip 81 of the rotated flap 41 that faces the recess 83 is inserted into the recess 83. Here, the turning tip 81 is the turning tip of the flap 41 and its vicinity.

  As shown in FIG. 2, the recording paper 16 is guided along a conveyance direction 80 (direction indicated by a dashed arrow in FIG. 2, an example of the conveyance direction of the present invention) from the rear side to the front side along the straight path 65 </ b> B. The When the recording paper 16 guided along the straight path 65B is supported by the platen 42 from below, the upper surface of the recording paper 16 faces the recording unit 24. An image is recorded on the upper surface by the recording unit 24.

[Module 50]
As shown in FIGS. 2 and 9, a first guide member 71 (first guide of the present invention) is provided inside the printer unit 11, specifically, below the recording unit 24 and above the sheet feeding unit 15. An example of a member), a second guide member 72 (an example of a second guide member of the present invention), a platen 42, a flap 41 described later, a detected part 73 described later (an example of a detected part of the present invention), and described later. A module 50 (see FIG. 9, an example of the module of the present invention) composed of the interlocking part 74 (an example of the interlocking part of the present invention) is disposed. That is, the first guide member 71, the second guide member 72, the platen 42, the flap 41, the detected part 73, and the interlocking part 74 constitute one module 50. As will be described later, the interlocking portion 74 includes a connecting portion 76 and a coil spring 75.

  As shown in FIG. 4, the first guide member 71 has a box shape in which the length in the front-rear direction 8 and the left-right direction 9 is long in the vertical direction 7 and the lower part is opened. A platen 42 is disposed on the upper surface of the first guide member 71. That is, the platen 42 is supported from the lower side by the first guide member 71. Further, as described above, the first guide member 71 defines the lower side of the straight path 65 </ b> B at a location where the recording unit 24 is not provided. That is, the first guide member 71 constitutes a part of the lower guide surface of the straight path 65B. Note that the first guide member 71 and the platen 42 may be integrally formed. In this case, the first guide member 71 including the platen 42 constitutes the entire lower guide surface of the straight path 65B. As described above, the first guide member 71 constitutes at least a part of the lower guide surface of the straight path 65B.

  As shown in FIG. 2, the first guide member 71 has an opening 77 (an example of the opening of the present invention). The position of the opening 77 in the front-rear direction 8 is the same as the position of a later-described media sensor 110 provided in the recording unit 24. Further, the position of the opening 77 in the left-right direction 9 is the same position as the position of the media sensor 110 when the recording unit 24 is positioned at a third position described later. Note that the recording unit 24 is movable in the left-right direction 9 as will be described later. As described above, the opening 77 of the first guide member 71 is provided at a position facing the media sensor 110 at the third position. Further, as will be described later, a detected portion 73 is disposed directly below the opening 77. That is, the opening 77 exposes the detected part 73.

  The second guide member 72 has a box shape in which the length in the front-rear direction 8 and the left-right direction 9 is longer than the length in the up-down direction 7 and the upper part is opened. The second guide member 72 is disposed to face the first guide member 71 on the lower side of the first guide member 71, that is, on the opposite side to the first guide member 71 and the recording unit 24. Further, as will be described later, the second guide member 72 constitutes at least a part of the upper guide surface of the reverse conveyance path 67.

  The second guide member 72 is integrated with the first guide member 71. Thereby, a space is formed between the first guide member 71 and the second guide member 72. And the to-be-detected part 73 and the interlocking | linkage part 74 are arrange | positioned in the said space. In other words, the detected part 73 and the interlocking part 74 are disposed between the first guide member 71 and the second guide member 72.

  The platen 42 is a generally thin plate-shaped member attached to the upper surface of the first guide member 71. The upper surface of the platen 42 forms a lower guide surface of the straight path 65B. On the upper surface of the platen 42, the recording paper 16 guided along the straight path 65B is supported. That is, the platen 42 supports the recording paper 16 guided along the straight path 65B from below.

  As will be described later, the flap 41 is rotatably attached to the second guide member 72. Further, the detected portion 73 is connected to the flap 41 via the connecting portion 76 of the interlocking portion 74. Further, the detected part 73 is connected to the first guide member 71 via a coil spring 75 of the interlocking part 74. The flap 41 may be rotatably attached to the first guide member 72. As described above, the platen 42, the flap 41, the detected portion 73, and the interlocking portion 74 are members constituting the module 50, that is, the first guide member 71, the second guide member 72, the platen 42, the flap 41, and the detected portion. It is supported only by the portion 73 and the interlocking portion 74.

[Recording unit 24]
As shown in FIG. 2, the recording unit 24 is provided above the straight path 65 </ b> B so as to face the platen 42. The recording unit 24 includes a carriage 40 that mounts the recording head 38 and reciprocates in the left-right direction 9 (direction orthogonal to the conveyance direction 80). The carriage 40 is connected to a belt (not shown) installed along the left-right direction 9, and the belt is connected to a carriage drive motor 103 (see FIG. 6). When the carriage drive motor 103 is driven under the control of a microcomputer 130 (see FIG. 6) described later, the belt to which the drive force is transmitted from the carriage drive motor 103 moves. As a result, the carriage 40 moves in the left-right direction 9.

  The recording unit 24 can move to a third position (an example of the third position of the present invention) and a fourth position (an example of the fourth position) by moving the carriage 40. Here, the third position is a position inside the recording paper 16 conveyed along the straight path 65B in the left-right direction 9, that is, a position superimposed on the recording paper 16 conveyed along the straight path 65B in the left-right direction 9. The third position is also the position of the recording unit 24 in a state where the media sensor 110 provided in the recording unit 24 and the opening 77 formed in the first guide member 71 face each other. When the attitude of the flap 41 is detected by the microcomputer 130 described later, the recording unit 24 is moved to the third position under the control of the microcomputer 130. The fourth position is a position on the inner side of the recording paper 16 conveyed along the straight path 65B in the left-right direction 9 in the same way as the third position. However, the fourth position is a position different from the third position in the left-right direction 9. When the microcomputer 130 detects whether or not the recording paper 16 is supported by the platen 42, the recording unit 24 is moved to the fourth position under the control of the microcomputer 130.

  Ink is supplied to the recording head 38 from an ink cartridge (not shown). The recording head 38 ejects ink from the nozzle 39 as fine ink droplets. As the carriage 40 reciprocates in the left-right direction 9, the recording head 38 is scanned with respect to the recording paper 16, and the recording surface of the recording paper 16 guided by the straight path 65B while being supported by the platen 42, that is, the recording paper 16 is provided. An image is recorded on the upper surface of. That is, the recording unit 24 records an image on the recording paper 16 supported by the platen 42 while moving in the left-right direction 9.

[Media sensor 110]
As shown in FIGS. 2 and 5, the media sensor 110 (an example of the sensor of the present invention) for detecting the recording paper 16 conveyed along the straight path 65B is on the lower surface side of the carriage 40 of the recording unit 24. The recording unit 24 is provided in the vicinity of the most upstream side in the conveyance direction 80.

  The media sensor 110 includes a light emitting unit 111 made of a light emitting diode or the like (an example of the light emitting unit of the present invention, see FIG. 6) and a light receiving unit 112 made of an optical sensor or the like (see an example of the light receiving unit of the present invention, see FIG. 6). And. The light emitting unit 111 emits light downward, that is, toward the platen 42 side. The irradiated light is reflected by the recording paper 16, the platen 42, or the detected portion 73 described later. The reflected light is received by the light receiving unit 112.

  In the media sensor 110 of the present embodiment, light having a certain intensity is emitted from the light emitting unit 111, and the intensity of reflected light of the emitted light is used as a detection result (an example of the detection result of the present invention). Then, the media sensor 110 outputs a signal corresponding to the intensity of the reflected light to a microcomputer 130 (see FIG. 6) described later. For example, the media sensor 110 outputs a signal having a larger value as the intensity of reflected light is higher.

  Here, the intensity of the constant light emitted from the light emitting unit 111 is set in advance based on the reflectance of the surfaces of the recording paper 16, the platen 42, and the detected unit 73 facing the respective media sensors 110. The For example, the intensity of light emitted from the light emitting unit 111 is such that when the irradiated light is reflected by each of the recording paper 16, the platen 42, and the detected part 73, the reflected light has different intensity. Is set. Therefore, since the intensity of the reflected light received by the light receiving unit 112 is different and the output signal is different, the microcomputer 130 can detect the recording paper 16, the platen 42, and the detected portion 73.

  The method for obtaining the detection result is not limited to the method described above. For example, the following method may be used. That is, the microcomputer 130 causes the light emitting unit 111 to emit light. At this time, the light emitting unit 111 is controlled by the microcomputer 130 so that the intensity of the irradiated light gradually increases. A signal output from the light receiving unit 112 that has received the reflected light of the irradiated light is input to the ASIC 135 (see FIG. 6) of the microcomputer 130. The input signal from the light receiving unit 112 increases as the intensity of irradiated light increases. The microcomputer 130 compares the input signal with a predetermined threshold value. When the input signal becomes larger than a predetermined threshold, the intensity of irradiation light corresponding to the input signal at that time is used as a detection result (an example of the detection result of the present invention). Then, a signal corresponding to the detection result by the light emitting unit 111 and the light receiving unit 112 is output from the media sensor 110 to the microcomputer 130. As described above, in this method, the level of the signal corresponding to the detection result increases as the light emitted from the light emitting unit 111 increases.

[Conveying roller pair 70]
As shown in FIG. 2, a conveyance roller pair 70 including a first conveyance roller 60 and a pinch roller 61 is provided upstream of the recording unit 24 in the conveyance direction 80. The pinch roller 61 is disposed below the first conveyance roller 60 and is pressed against the first conveyance roller 60 by an elastic member such as a spring (not shown).

  The first transport roller 60 is forwardly or reversely rotated when a driving force in the forward / reverse rotation direction is transmitted from the transport motor 102 (see FIG. 6). For example, when the forward driving force is transmitted from the transport motor 102, the first transport roller 60 is rotated in the direction of transporting the recording paper 16 in the transport direction 80, and is driven in the reverse direction from the transport motor 102. When the force is transmitted, the recording paper 16 is rotated in a direction in which the recording paper 16 is conveyed in the direction opposite to the conveyance direction 80. That is, the conveyance roller pair 70 conveys the recording paper 16 in the conveyance direction 80 when a driving force in the normal rotation direction is transmitted from the conveyance motor 102.

[Discharge roller pair 44]
On the downstream side of the recording unit 24 in the conveying direction 80, specifically, in the downstream side of the conveying direction 80 from the first position 36, which will be described later, a discharge roller pair 44 composed of a second conveying roller 45 and a spur 46 (in the present invention). An example of a transport unit) is provided. The spur 46 is disposed above the second transport roller 45 and is pressed against the roller surface of the second transport roller 45 by an elastic member such as a spring (not shown).

  The second transport roller 45 is rotated forward or reversely by receiving a driving force in the forward / reverse rotation direction from the transport motor 102 (see FIG. 6, an example of the drive source of the present invention). That is, the conveyance motor 102 applies the following two driving forces to the second conveyance roller 45. The two driving forces are a first driving force (an example of the first driving force of the present invention) that rotates the second conveying roller 45 in one of normal rotation and reverse rotation (normal rotation in the present embodiment), and a second conveying roller. This is a second driving force (an example of the second driving force of the present invention) that rotates 45 to the other of forward rotation and reverse rotation (reverse rotation in the present embodiment). When the second transport roller 45 rotates with the first driving force applied, the recording paper 16 sandwiched between the discharge roller pair 44 is transported in the transport direction 80. On the other hand, when the second transport roller 45 rotates with the second driving force applied, the recording paper 16 sandwiched between the discharge roller pair 44 is transported in the direction opposite to the transport direction 80 (an example of the reverse transport direction of the present invention). Is done.

  For example, when single-sided recording is performed, the second transport roller 45 rotates forward. As a result, the recording paper 16 is sandwiched between the discharge roller pair 44 and conveyed downstream, and is discharged onto the paper discharge tray 21. On the other hand, when duplex recording is performed, the rotation direction of the second conveyance roller 45 is switched from normal rotation to reverse rotation with the discharge roller pair 44 sandwiching the rear end portion of the conveyance direction 80 of the recording paper 16. As a result, the recording paper 16 is nipped by the discharge roller pair 44 and conveyed in the direction opposite to the conveyance direction 80, guided by a flap 41 described later, and conveyed in a reverse conveyance path 67 described below.

[Reverse conveying path 67]
As shown in FIG. 3, the reverse conveyance path 67 (an example of the second conveyance path of the present invention) includes a first position 36 (an example of the first position of the present invention) and a second position 37 (a second conveyance path of the present invention). In an example of the position), it is connected to the conveyance path 65. Here, the first position 36 is a position downstream of the recording unit 24 and upstream of the discharge roller pair 44 in the conveyance direction 80 of the conveyance path 65. The second position 37 is a position upstream of the conveyance roller pair 70 in the conveyance direction 65 in the conveyance direction 80, that is, a position upstream of the recording unit 24 in the conveyance direction 80.

  The reverse conveying path 67 extends on the lower side of the platen 42 and on the upper side of the paper feeding unit 15. The reverse conveyance path 67 is partitioned on the upper side by the second guide member 72 and the inner guide member 19. The reverse conveyance path 67 is partitioned by the first lower guide member 31 and the second lower guide member 32 on the lower side.

  The recording paper 16 is conveyed in the direction opposite to the conveyance direction 80 by the discharge roller pair 44, and is conveyed along the reverse conveyance path 67 from the first position 36 to the second position 37.

[Flap 41]
As shown in FIG. 2, the flap 41 is rotatably attached to the second guide member 72. That is, the flap 41 is provided below the straight path 65B. Further, as shown in FIG. 3, the flap 41 is located below the first position 36. That is, the flap 41 is disposed below the straight path 65 </ b> B at the first position 36.

  As shown in FIG. 5, shafts 43 projecting outward are formed at both ends of the flap 41 in the left-right direction 9. On the other hand, a hole (not shown) is formed in the second guide member 72. A shaft 43 is inserted into the hole. As a result, the flap 41 rotates in the direction of the arrow 58 with the shaft 43 as the rotation center.

  The flap 41 rotates between a first posture shown in FIG. 3 (an example of the first posture of the present invention) and a second posture shown in FIG. 2 (an example of the second posture of the present invention).

  As shown in FIG. 3, in the first posture, the upper surface 56 of the flap 41 (an example of the upper surface of the present invention) is continuous with the upper surface of the platen 42. Thus, the recording paper 16 conveyed along the straight path 65B is guided and conveyed by the upper surface of the platen 42, and then guided and conveyed by the upper surface 56 of the flap 41. That is, the upper surface 56 of the flap 41 constitutes a lower guide surface of the straight path 65B.

  Further, the flap 41 in the first posture sandwiches the recording paper 16 between the upper guide member 82 and a spur 63 that is rotatably attached to the upper end of the flap 41 so as to face the rotating tip 81. That is, the recording paper 16 guided along the upper surface 56 of the flap 41 is further conveyed by at least one of the conveying roller pair 70 or the discharge roller pair 44 while being sandwiched between the rotating tip 81 and the spur 63 of the flap 41. It is conveyed downstream in the direction 80.

  As shown in FIG. 2, in a state where the flap 41 is in the second posture, the rotation tip portion 81 of the flap 41 is positioned above the first posture and is a recess 83 formed in the upper guide member 82. Inserted into. That is, the flap 41 in the second posture closes the straight path 65B.

  Further, the lower surface 57 (an example of the lower surface of the present invention) of the flap 41 defines the upper side of the reverse conveyance path 67 in a state where the flap 41 is in the second posture. That is, the lower surface 57 of the flap 41 constitutes an upper guide surface of the reverse conveyance path 67. The recording paper 16 is guided along the reverse conveyance path 67 along the lower surface 57 of the flap 41.

[Detected part 73]
As shown in FIG. 2, the detected part 73 is disposed between the first guide member 71 and the second guide member 72. As shown in FIG. 5, the detected portion 73 is a member that is long in the front-rear direction 8.

  As shown in FIGS. 2 and 3, the detected part 73 is arranged in the front-rear direction 8 so that at least a part thereof is located directly below the opening 77 formed in the first guide member 71. That is, the detected unit 73 is provided at a position that can face the media sensor 110 of the recording unit 24 moved to the third position. As will be described later, the detected portion 73 is slidably attached to a long hole 84 formed in the flap 41.

  As shown in FIGS. 4 and 5, the detected portion 73 is disposed in a position facing the position other than the first range 68 (see FIG. 4) in the left-right direction 9. Here, the first range 68 is the edge 9 in the left-right direction (the edge and its vicinity, the edge of the present invention) of the recording paper 16 of the predetermined size when the recording paper 16 of the predetermined size is supported by the platen 42. Part). Here, the predetermined size is a standard size set in advance as a size for recording an image by the recording unit 24 in the multifunction machine 10, and is a size such as A4 or B5, for example. In the present embodiment, the first range 68 is formed at four locations, but only three locations are shown in FIG. 4, and the remaining one location is hidden behind the recording unit 24 and cannot be seen.

  As shown in FIG. 4, the platen 42 is formed with an ink flow path 47 for guiding the ink ejected on the platen 42 from the upper surface to the lower surface of the platen 42. The recording unit 24 ejects ink to the second range 69 in the front-rear direction 8 of the recording paper 16 when performing borderless printing on the recording paper 16. When borderless printing is performed on the recording paper 16, the ink ejected from the recording unit 24 is not only the recording paper 16 but also the upper surface of the platen 42 near the edge in the left-right direction 9 of the recording paper 16, that is, the first range. 68 also adheres. The ink flow path 47 is for guiding the ink adhering to the upper surface of the platen 42 to the lower surface of the platen 42. Thereby, it is possible to prevent the ink attached to the platen 42 from adhering to the subsequent recording paper 16 and soiling the recording paper 16. Note that the reason why the ink flow path 47 is formed outside the first range 68 on the front side of the second range 69 is that the ink adhered to the edge in the front-rear direction 8 of the recording paper 16 is removed from the upper surface of the platen 42. This is to lead to the lower surface.

  As shown in FIGS. 2 and 3, a first surface 78 (an example of the first surface of the present invention) and a second surface 79 (an example of the second surface of the present invention) are formed on the upper surface of the detected portion 73. Is formed. The first surface 78 and the second surface 79 are made of materials having different reflectances. In the present embodiment, the reflectance of the first surface 78 is configured to be greater than the reflectance of the second surface 79.

  The detected portion 73 is connected to the third posture (the posture shown in FIG. 3, an example of the third posture of the present invention) and the fourth posture (the posture shown in FIG. The posture changes to (an example of four postures).

  When the detected portion 73 is in the third posture (the posture shown in FIG. 2), the first surface 78 of the detected portion 73 is located directly below the opening 77 of the first guide member 71. When the recording unit 24 is in the third position, the media sensor 110 is positioned immediately above the opening 77 of the first guide member 71. Therefore, when the detected part 73 is in the third posture, the first surface 78 faces the media sensor 110 at the third position.

  When the detected portion 73 is in the fourth posture (the posture shown in FIG. 3), the second surface 79 of the detected portion 73 is located directly below the opening 77 of the first guide member 71. When the recording unit 24 is in the third position, the media sensor 110 is positioned immediately above the opening 77 of the first guide member 71. Therefore, when the detected portion 73 is in the fourth posture, the first surface 78 does not face the media sensor 110 at the third position, and the second surface 79 faces the sensor at the third position.

[Interlocking part 74]
As shown in FIG. 2, the interlocking portion 74 includes a connecting portion 76 (an example of the connecting portion of the present invention) and a coil spring 75 (an example of the first urging member and the second urging member of the present invention). Yes.

  As shown in FIGS. 2, 3, and 5, the connecting portion 76 includes a long hole 84 formed in the flap 41 in the vertical direction 7 and a protrusion 85 formed in the detected portion 73. ing. As shown in FIG. 5, the long hole 84 is formed in a pair of side plates provided slightly to the right in the center in the left-right direction 9 of the flap 41. The protrusion 85 is provided near the front end of the right side plate and the left side plate of the detected portion 73. The protrusion 85 is inserted through the long hole 84. As described above, the detected portion 73 is attached to the flap 41 so as to be slidable along the long hole 84. That is, the connecting portion 76 connects one end (front end) of the detected portion 73 and the flap 41.

  As shown in FIG. 2, one end of the coil spring 75 is connected to a hooking portion 86 provided at the rear end of the detected portion 73, and the other end of the coil spring 75 is hooked to the first guide member 71. 87. In FIG. 5, the description of the hook portion 86 of the detected portion 73 is omitted.

  As described above, when the coil spring 75 is connected to the detected portion 73 and the first guide member 71, the detected portion 73 is moved to the rear side (that is, the other end side of the coil spring 75 by the force of the coil spring 75 trying to contract). ). Thereby, the detected part 73 is changed in posture to the third posture. That is, the coil spring 75 biases the detected portion 73 to the other end side and changes the posture to the third posture. Further, since the flap 41 is connected to the coil spring 75 via the detected portion 73, the flap 41 is pulled rearward by a force that the coil spring 75 tries to contract, that is, by being biased by the coil spring 75. Thereby, the posture of the flap 41 is changed to the second posture. That is, the coil spring 75 biases the flap 41 toward the second posture side. In other words, it can be said that the flap 41 changes the posture of the detected part 73 to the third posture by changing the posture to the second posture.

  The biasing force of the coil spring 75 is smaller than the weight of the recording paper 16. As a result, when the upper surface of the flap 41 in the second posture (the posture shown in FIG. 2) supports the recording paper 16 conveyed on the straight path 65B, the flap 41 is attached to the coil spring 75 by its own weight. It turns from the second posture to the first posture (the posture shown in FIG. 3) against the force. The flap 41 pulls the detected portion 73 forward while rotating from the second posture to the first posture. Accordingly, the detected portion 73 is changed in posture from the third posture to the fourth posture against the urging force of the coil spring 75.

  As described above, the interlocking unit 74 changes the posture of the detected unit 73 to one of the third posture and the fourth posture (the fourth posture in the present embodiment) in conjunction with the posture change of the flap 41 to the first posture. In conjunction with the posture change of the flap 41 to the second posture, the detected portion 73 is changed in posture to the other of the third posture and the fourth posture (the third posture in the present embodiment).

  In this embodiment, the coil spring 75 is used for biasing the flap 41 and the detected portion 73. However, if the flap 41 and the detected portion 73 are biased, instead of the coil spring 75, the coil spring 75 is used. Other urging members such as leaf springs may be used.

[Seat sensor 120]
As shown in FIG. 2, the printer unit 11 includes a sheet sensor 120 for detecting the recording paper 16 fed from the paper feed tray 20 and conveyed through the curved path 65A. The sheet sensor 120 is provided downstream of the second position 37 (see FIG. 3) in the curved path 65 </ b> A and upstream of the conveyance roller pair 70.

  The sheet sensor 120 includes, for example, a photo interrupter having a rotating body 121 that rotates about a shaft 123, a light emitting element (for example, a light emitting diode), and a light receiving element (for example, a phototransistor) that receives light emitted from the light emitting element. The optical sensor 122 is configured. The shaft 123 of the rotating body 121 is rotatably attached to, for example, the inner guide member 19 such as a frame of the multifunction machine 10. The tip of the rotator 121 protrudes into the curved path 65A.

  In a state where the recording paper 16 is not in contact with the rotating body 121, the end of the rotating body 121 enters the optical path from the light emitting element to the light receiving element of the optical sensor 122 as shown in FIG. The light passing through is blocked. When the recording paper 16 being conveyed comes into contact with the rotator 121 and pushes the rotator 121, the end of the rotator 121 is removed from the optical path, and light passes through the optical path. On the other hand, when the rear end 80 of the transported recording paper 16 passes through the rotating body 121, the rear portion of the rotating body 121 enters the optical path and blocks light passing through the optical path.

  The optical sensor 122 is connected to a microcomputer 130 (see FIG. 6) described later. For example, when light passes through the optical path, the optical sensor 122 outputs a high level signal to the microcomputer 130, and when the optical path is blocked by the rotating body 121, the optical sensor 122 outputs a low level signal. The data is output to the microcomputer 130. The microcomputer 130 detects the leading edge and the trailing edge of the recording paper 16 in the conveyance direction 80 based on the signal input from the optical sensor 122.

  As shown in FIG. 6, the printer unit 11 includes a rotary encoder 124. The rotary encoder 124 is attached to the shaft of the first transport roller 60, and is composed of an encoder disk (not shown) that rotates the first transport motor 60 and an optical sensor (not shown). The rotary encoder 124 detects a pattern formed on the encoder disk with an optical sensor. The signal detected by the optical sensor of the rotary encoder 124 is output to the microcomputer 130 described later.

  The microcomputer 130 is connected to the optical sensor of the rotary encoder 124, and calculates the rotation amount of the first transport roller 60 based on a signal input from the optical sensor. The microcomputer 130 can grasp the position of the recording paper 16 based on the recording paper 16 detected by the sheet sensor 120 and the calculated rotation amount of the first conveying roller 60. As described above, the sheet sensor 120, the rotary encoder 124, and the microcomputer 130 are examples of the sheet detection unit of the present invention.

[Microcomputer 130]
As shown in FIG. 6, the microcomputer 130 controls the overall operation of the multifunction machine 10. For example, the microcomputer 130 controls the carriage drive motor 103 to move the recording unit 24 in the left-right direction 9. The microcomputer 130 includes a CPU 131, ROM 132, RAM 133, EEPROM 134, and ASIC 135. These are connected by an internal bus 137.

  The ROM 132 stores a program for the CPU 131 to control various operations. The RAM 133 is used as a storage area for temporarily recording data and signals used when the CPU 131 executes the program, or as a work area for data processing. The EEPROM 134 stores settings, flags, and the like that should be retained even after the power is turned off.

  A paper feed motor 101 and a transport motor 102 are connected to a drive circuit provided in the ASIC 135. When a drive signal for driving each motor is input from the CPU 131 to a drive circuit corresponding to a predetermined motor, a drive current corresponding to the drive signal is output from the drive circuit to the corresponding motor. As a result, the corresponding motor rotates forward or reverse at a predetermined rotational speed.

  The media sensor 110 is connected to the ASIC 135. As a result, signals described below are input to the ASIC 135.

  For example, in the present embodiment, when the recording unit 24 is in the third position, as shown in FIG. 2, the detected unit 73 is in the third posture in conjunction with the posture change of the flap 41 to the second posture. When the posture is changed, the media sensor 110 faces the first surface 78 of the detected portion 73 having a large reflectance (easy to be reflected). In this case, since the intensity of the reflected light is increased, a high level signal is output from the media sensor 110 and input to the ASIC 135.

  On the other hand, in the present embodiment, when the recording unit 24 is in the third position, when the detected unit 73 changes its posture to the fourth posture in conjunction with the posture change of the flap 41 to the first posture, the media sensor 110 opposes the 2nd surface 79 of the to-be-detected part 73 with a small reflectance (it is hard to reflect). In this case, since the intensity of the reflected light becomes weak, a low level signal is output from the media sensor 110 and input to the ASIC 135.

  As described above, when the flap 41 changes its posture from the first posture to the second posture in the state where light is emitted from the light emitting unit 111 of the media sensor 110 toward the detected portion 73, the reflecting unit 112 changes the state to the microcomputer 130. The input signal is switched from low level to high level. On the other hand, when the flap 41 changes its posture from the second posture to the first posture in a state where light is emitted from the light emitting portion 111 of the media sensor 110 toward the detected portion 73, the input from the reflecting portion 112 to the microcomputer 130 is performed. The signal to be switched is switched from the high level to the low level.

  In the present embodiment, when the recording unit 24 is in the fourth position and the recording sheet 16 is present on the platen 42, that is, a recording sheet that is a bright color such as white and easily reflects light. When 16 faces the light emitting unit 111, a low level signal is input to the ASIC 135. Thereby, the microcomputer 130 determines that the recording paper 16 is supported by the platen 42.

  On the other hand, in the present embodiment, when the recording unit 24 is in the fourth position, when the recording paper 16 does not exist on the platen 42, that is, the platen 42 is dark color such as black and hardly reflects light. When the upper surface of the LED is opposed to the light emitting unit 111, a high level signal is input to the ASIC 135. Thereby, the microcomputer 130 determines that the recording paper 16 is not supported by the platen 42.

  Further, as described above, the optical sensor 122 of the sheet sensor 120 is connected to the ASIC 135. Further, as described above, the optical sensor of the rotary encoder 124 is connected to the ASIC 135.

  Hereinafter, based on the flowchart of FIG. 10, the posture change of the flap 41 and the reversing process of the second transport motor 45 by the microcomputer 130 will be described. In the initial state, the flap 41 and the detected portion 73 maintain the second posture and the third posture, respectively, by the biasing force of the coil spring 75 as shown in FIG. Accordingly, a high level signal is input from the media sensor 110 to the microcomputer 130, and the microcomputer 130 determines that the flap 41 is in the second posture.

  When double-sided printing is instructed by operating the operation panel 12 (see FIG. 1), the microcomputer 130 rotates the paper feed motor 101 and the conveyance motor 102 in the normal direction. Then, the paper feed roller 25, the first transport roller 60, and the second transport roller 45 rotate in the normal direction. As a result, the recording paper 16 placed on the paper feed tray 20 is transported in the transport direction 80 along the transport path 65 (S10). That is, the transport motor 102 applies a first driving force to the second transport roller 45.

  When the leading end 80 of the recording paper 16 conveyed by the paper feed roller 25 abuts against the rotating body 121 of the sheet sensor 120 and presses the rotating body 121, the optical sensor 122 of the sheet sensor 120 outputs a high level signal to the micro level. The data is output to the computer 130. The microcomputer 130 (i) recognizes the position of the leading end of the recording sheet 16 in the conveyance direction 80 based on the input of the signal. Further, the microcomputer 130 (ii) calculates the rotation amount of the first transport roller 60 based on the input from the optical sensor of the rotary encoder 124. From the above (i) and (ii), the microcomputer 130 recognizes the position of the recording paper 16 in the conveyance path 65 after the recording paper 16 comes into contact with the rotating body 121.

  Thereafter, the recording paper 16 conveyed by the paper supply roller 25 is sandwiched between the conveyance roller pair 70. Thereby, the recording paper 16 is conveyed by the conveyance roller pair 70 (S20).

  When the microcomputer 130 determines that the leading edge of the recording paper 16 has reached the printing start position according to the above (i) and (ii), the microcomputer 130 controls the recording unit 24 to record an image on the surface of the recording paper 16 (S30). ). Whether the recording paper 16 is definitely supported on the platen 42 by moving the recording unit 24 to the fourth position and controlling the media sensor 110 before the start of image recording. May be detected.

  In image recording, ejection of ink droplets by the recording unit 24 and conveyance of the recording paper 16 for a predetermined distance (for a line feed) are alternately executed. When the image recording is completed, the recording paper 16 is transported in the transport direction 80 by at least one of the transport roller pair 70 or the discharge roller pair 44 (S40).

  After the image recording on the surface of the recording paper 16 by the recording unit 24 has been completed, the microcomputer 130 has transported the rear end 80 of the recording paper 16 to a predetermined position (an example of the predetermined position of the present invention). Is determined (S50). Here, the predetermined position is a position upstream of the conveyance direction 80 from the position where the rear end of the recording sheet 16 in the conveyance direction 80 passes through the flap 41. For example, the position in the straight path 65B is downstream of the recording unit 24 in the transport direction 80 and upstream of the flap 41 in the transport direction 80.

  If the microcomputer 130 determines that the recording paper 16 has been transported to the predetermined position according to (i) and (ii) above, the microcomputer 130 moves the recording unit 24 to the third position (S60). The microcomputer 130 starts irradiating light from the light emitting unit 111. That is, the microcomputer 130 controls the media sensor 110 and acquires an output signal from the media sensor 110 (S70). Note that the conveyance of the recording paper 16 in the conveyance direction is continued between steps S50 to S70 (S80).

  As shown in FIG. 2, when the flap 41 is in the second posture, the detected part 73 is in the third posture, so the first surface 78 is opposed to the media sensor 110. As a result, a high level signal is input to the ASIC 135. Thereby, the microcomputer 130 determines that the flap 41 is in the second posture. On the other hand, when the flap 41 is in the first posture, the detected part 73 is in the fourth posture, so the second surface 79 faces the media sensor 110. As a result, a low level signal is input to the ASIC 135. Thereby, the microcomputer 130 determines that the flap 41 is in the first posture. The control for determining the posture of the flap 41 by the microcomputer 130 described above is an example of the determination unit of the present invention.

  At the time when step S70 is started, the recording paper 16 conveyed downstream from the recording unit 24 is supported on the upper surface of the flap 41. Accordingly, the posture of the flap 41 is changed from the second posture to the first posture due to the weight of the recording paper 16. Therefore, a low level signal is input from the media sensor 110 to the microcomputer 130 when the step S70 is started. Thereby, the microcomputer 130 determines that the flap 41 is in the first posture at the time point when Step S70 is started.

  The microcomputer 130 determines whether or not the signal input from the media sensor 110 has changed from the low level to the high level, that is, whether or not the flap 41 has changed from the first position to the second position (S90). . As described above, since the signal input from the media sensor 110 to the microcomputer 130 is at the low level and the low level is maintained at the time when Step S70 is started, that is, the flap 41 maintains the first posture. (S90: No), the light irradiation from the light emitting unit 111 (S70) and the conveyance of the recording paper 16 in the conveyance direction 80 (S80) are continued.

  Thereafter, when the rear end of the transport direction 80 of the transported recording paper 16 passes through the flap 41, the posture of the flap 41 is changed from the first posture to the second posture by the biasing force of the coil spring 75. As a result, a high level signal is input from the media sensor 110 to the microcomputer 130. That is, the signal input from the media sensor 110 to the microcomputer 130 is switched from the low level to the high level. Thereby, the microcomputer 130 determines that the posture of the flap 41 has been changed from the first posture to the second posture (S90: Yes).

  The microcomputer 130 that has determined that the posture of the flap 41 has been changed from the first posture to the second posture controls the conveyance motor 102 to apply a driving force applied to the second conveyance roller 45 constituting the discharge roller pair 44. The first driving force is switched to the second driving force (S100). The switching control of the driving force by the microcomputer 130 in step S100 is an example of the transport control unit of the present invention.

  When the driving force applied to the second conveying roller 45 is switched from the first driving force to the second driving force, the rotation direction of the second conveying roller 45 changes from normal rotation to reverse rotation (S100). As a result, the recording paper 16 sandwiched between the discharge roller pair 44 is conveyed in a direction opposite to the conveyance direction 80. At this time, since the straight path 65B is blocked by the flap 41 whose posture has been changed to the second attitude, the recording paper 16 is conveyed along the reverse conveyance path 67 while being guided by the lower surface of the flap 41 (S110). .

  The recording sheet 16 conveyed through the reverse conveyance path 67 passes through the second position 37 and is again sandwiched between the conveyance roller pair 70. Thereby, the recording paper 16 is conveyed along the conveyance path 56 by the conveyance roller pair 70 (S120). Thereafter, the recording paper 16 conveyed by the conveying roller pair 70 reaches the position immediately below the recording unit 24 again. At this time, the back surface of the recording paper 16 faces the recording unit 24. The recording unit 24 records an image on the back surface of the recording paper 16 (S130). As a result, images are recorded on both sides of the recording paper 16. Thereafter, the recording paper 16 is discharged to the paper discharge tray 21 through the discharge roller pair 44 (S140).

[Effect of the embodiment]
In the present embodiment, the recording unit 24 is provided to face the platen 42. Therefore, the media sensor 110 provided in the recording unit 24 is also provided facing the platen 42. Therefore, the media sensor 110 can be used to detect whether or not the recording paper 16 is supported on the platen 42. For example, when the magnitude of the reflected light of the light emitted toward the platen 42 by the light emitting unit 111 is larger than a preset threshold value, it is detected that the recording paper 16 is supported by the platen 42, and the reflected light Is equal to or smaller than the threshold value, it is detected that the recording paper 16 is not supported by the platen 42.

  In the present embodiment, the detected portion 73 changes its posture in conjunction with the change of the posture of the flap 41. Specifically, the detected part 73 changes its posture between a posture in which the first surface 78 faces the media sensor 110 and a posture in which the first surface 78 does not face the media sensor 110. In this embodiment, the determination unit controls the media sensor 110 with the media sensor 110 and the detected unit 73 facing each other. Then, the determination unit determines the attitude of the flap 41 based on a signal that varies depending on whether or not the media sensor 110 faces the first surface 78.

  That is, in this embodiment, in order to detect the posture of the flap 41, a sensor for detecting whether or not the recording paper 16 is supported on the platen 42 can be used. That is, according to this embodiment, it is not necessary to provide a dedicated sensor for detecting the posture of the flap 41.

  Further, according to the present embodiment, the light emitted from the light emitting unit 111 is reflected by the first surface 78 and the second surface 79. That is, the first surface 78 and the second surface 79 are light reflecting surfaces. Therefore, in the present embodiment, by setting the first surface 78 and the second surface 79 to the same height, the distance between the media sensor 110 and the light reflection surface can be made the same. As a result, the detection accuracy of the media sensor 110 can be improved.

  According to the present embodiment, since the platen 42, the flap 41, the detected portion 73, and the interlocking portion 74 constitute one module 50, the above-described members constituting the module 50 are added to the multifunction device 10. When assembling, it is not necessary to assemble each member individually. That is, the platen 42, the flap 41, the detected part 73, and the interlocking part 74 can be easily assembled to the multifunction machine 10.

  When performing so-called borderless printing, a recording material (which is attached to the recording paper 16 by the recording unit 24 on the platen 42 at the edge of the recording paper 16 to be printed (the edge of the recording paper 16 and the vicinity thereof) (see FIG. In this embodiment, ink) remains. If the remaining ink adheres to the first surface 78 and the second surface 79 of the detected portion 73, an error may occur in the detection result by the media sensor 110. However, according to the present embodiment, the detected part 73 is arranged at a position other than the edge part. Therefore, according to the present embodiment, the possibility of ink adhering to the detected portion 73 can be reduced.

  Further, according to the present embodiment, the position of the recording unit 24 (third position) when determining the posture of the flap 41 is the recording unit when determining whether or not the recording paper 16 is supported by the platen 42. This is different from the 24 position (fourth position). Accordingly, the recording paper 16 supported by the platen 42 is irradiated with light to determine the posture of the flap 41, or the detected portion 73 is irradiated with light to determine whether the recording paper 16 is supported by the platen 42. Can be prevented, that is, misjudgment.

  In the present embodiment, when the flap 41 supports the recording paper 16 on the upper surface, the flap 41 takes the first posture due to the weight of the recording paper 16. Further, when the flap 41 does not support the recording paper 16, the flap 41 is biased by the coil spring 75 and takes the second posture. That is, the flap 41 takes the first posture when the recording paper 16 is supported on the upper surface thereof, and changes its posture from the first posture to the second posture when the recording paper 16 passes the flap 41. According to this embodiment, at this time, the drive of the second conveyance roller 45 of the discharge roller pair 44 is reversed by the conveyance control unit, and the recording paper 16 is reversely fed. Thereby, the recording paper 16 can be guided to the reverse conveyance path 67.

  In the present embodiment, when images are recorded on both sides of the recording paper 16, the posture of the flap 41 is changed from the first posture to the second posture after the trailing end 80 of the recording paper 16 in the transport direction 80 passes through the flap 41. Is done. As a result, the recording paper 16 is transported from the transport path 65 to the reverse transport path 67 and then transported again through the transport path 65 to reach the recording unit 24 in a state where an image can be recorded on the back surface. According to the present embodiment, the determination unit moves the recording unit 24 to the third position slightly before the trailing end 80 of the recording paper 16 in the conveyance direction 80 passes the flap 41. Thereby, the determination part can detect the attitude | position change of the flap 41 reliably.

[Modification 1]
In the above-described embodiment, when the detected portion 73 is in the third posture, the first surface 78 faces the media sensor 110 at the third position, and when the detected portion 73 is in the fourth posture, the second surface 79 is the first posture. Opposite the three-position media sensor 110. However, as shown in FIGS. 7 and 8, the detected portion 73 does not have to include the second surface 79. In this case, when the detected portion 73 is in the third posture, as shown in FIG. 7, the first surface 78 faces the media sensor 110 at the third position, and the detected portion 73 is in the fourth posture. As shown in FIG. 8, the detected portion 73 does not face the media sensor 110 at the third position.

  Therefore, in the first modification, when the detected part 73 changes its posture to the third posture in conjunction with the posture change of the flap 41 to the second posture, as shown in FIG. It faces the first surface 78 of the detected part 73 having a large (easy to be reflected). As a result, a high level signal is input to the microcomputer 130.

  On the other hand, when the detected portion 73 changes to the fourth posture in conjunction with the posture change of the flap 41 to the first posture, the media sensor 110 faces the detected portion 73 as shown in FIG. do not do. Instead, the media sensor 110 faces the second guide member 72 located below the detected portion 73. Here, the 2nd guide member 72 is comprised by dark colors, such as black. Then, the reflectance of the second guide member 72 becomes small. As a result, a low level signal is input to the microcomputer 130.

[Modification 2]
In the above-described embodiment, the position of the detected portion 73 in the left-right direction 9 is a position inside the recording paper 16 conveyed along the straight path 65B. And by forming the opening 77 in the first guide member 71, the detected portion 73 and the media sensor 110 of the recording portion 24 at the third position are opposed to each other.

  However, the position of the detected portion 73 in the left-right direction 9 may be a position outside the recording paper 16 conveyed along the straight path 65B. In this case, the detected part 73 is provided on the right side or the left side of the first guide member 71. Therefore, the recording unit 24 moves the media sensor 110 and the detected portion 73 to face each other by moving to a position that does not face the first guide member 71. Therefore, in the second modification, the opening 77 for making the detected portion 73 and the media sensor 110 face each other may not be formed in the first guide member 71.

  On the other hand, the recording paper 16 conveyed along the straight path 65B is positioned inside the left-right direction 9 relative to the first guide member 71 that defines the straight path 65B. As described above, in the second modification, the third position is a position outside the recording sheet 16 conveyed along the straight path 65B in the left-right direction 9, and the fourth position is conveyed along the straight path 65B in the left-right direction 9. It is a position inside the recording paper 16.

16 ... Recording paper 24 ... Recording section 41 ... Flap 42 ... Platen 65 ... Conveyance path 67 ... Reverse conveyance path 68 ... First range 71 ... First guide member 72 ... second guide member 73 ... detected portion 74 ... interlocking portion 75 ... coil spring 77 ... opening 78 ... first surface 79 ... second surface 80 ... transport Direction 110 ... Media sensor

Claims (9)

A first conveyance path for guiding the sheet in the conveyance direction;
A support portion for supporting the sheet guided along the first conveyance path from below;
A recording unit that is provided above the support unit so as to face the support unit, and that records an image on a sheet supported by the support unit while moving in a direction orthogonal to the transport direction;
A conveyance path that extends below the support unit and guides the sheet, and has a first position downstream in the conveyance direction with respect to the recording unit, and an upstream side in the conveyance direction with respect to the recording unit. A second transport path connected to the first transport path at the second position of
A first posture that is disposed below the first conveyance path in the first position, and whose upper surface constitutes a lower guide surface of the first conveyance path, and that guides the sheet along the upper surface; and A flap that closes the first conveyance path, the lower surface constitutes an upper guide surface of the second conveyance path, and rotates to a second posture that guides the sheet along the lower surface;
The recording unit is provided with a light emitting unit that emits light and a light receiving unit that receives reflected light of the light emitted by the light emitting unit, and a signal based on a detection result by the light emitting unit and the light receiving unit An output sensor;
The recording unit moved to the third position is provided at a position that can be opposed to the sensor, and the first surface is opposed to the sensor at the third position, and the first surface is the third position. A detected portion that changes its posture to a fourth posture that does not face the position sensor;
In conjunction with a change in the posture of the flap to the first posture, the detected portion is changed to one of the third posture or the fourth posture, and the posture of the flap is changed to the second posture. An interlocking unit that changes the detected portion to the other of the third posture or the fourth posture;
An image recording apparatus comprising: a determination unit that moves the recording unit to the third position to control the sensor and determines an attitude of the flap based on a signal output from the sensor.   The detected portion has a second surface having a reflectance different from that of the first surface, and the second surface faces the sensor at the third position in the fourth posture. The image recording apparatus described. The support part, the flap, the detected part, and the interlocking part constitute one module,
The image recording apparatus according to claim 1, wherein the support portion, the flap, the detected portion, and the interlocking portion are supported only by members that constitute the module. A first guide member that supports the support and constitutes at least part of a lower guide surface of the first conveyance path;
The first guide member is assembled to the first guide member so as to face the recording head opposite to the opposite side, and constitutes at least a part of the upper guide surface of the second transport path. A guide member,
The flap is attached to the first guide member or the second guide member,
The detected part and the interlocking part are disposed between the first guide member and the second guide member,
The image recording apparatus according to claim 3, wherein the first guide member has an opening that exposes the detected portion at a position facing the sensor at the third position.   The arrangement position of the detected part in the direction orthogonal to the transport direction is the standard size when a sheet of a standard size preset as a size for recording an image by the recording unit is supported by the support unit. The image recording apparatus according to claim 1, wherein the image recording apparatus is located at a position other than an edge portion in a direction orthogonal to the conveyance direction of the sheet.   A fourth position facing the support portion where the recording unit moves to determine whether or not the sheet is supported by the support portion is different from the third position in a direction orthogonal to the transport direction. The image recording apparatus according to claim 1, wherein the image recording apparatus is a position. A first biasing member that biases the flap toward the second posture;
A transport unit that is provided on the downstream side of the transport direction from the first position, and transports the sheet in the transport direction and in a reverse transport direction opposite to the transport direction;
A driving source for applying a first driving force for conveying the sheet in the conveying direction to the conveying unit and a second driving force for conveying the sheet in the reverse conveying direction;
Condition that the determination that the driving source is applying the first driving force to the transport unit and that the posture of the flap is changed from the first posture to the second posture is made by the determination unit. The image recording apparatus according to claim 1, further comprising: a conveyance control unit that controls the driving source to apply the second driving force to the conveyance unit. The above interlocking part
A connecting part for connecting one end of the detected part and the flap;
A second urging member that is connected to the other end of the detected part, urges the detected part toward the other end side, and changes the posture to the fourth posture;
The flap is urged by the second urging member through the detected part and changed in posture to the second posture,
The detected portion is moved from the fourth position to the third position against the urging force of the second urging member by changing the position of the flap from the second position to the first position. The image recording apparatus according to claim 1, wherein the image recording apparatus is changed. A sheet detection unit that detects that the rear end of the sheet in the conveyance direction is conveyed to a predetermined position on the upstream side in the conveyance direction with respect to a position passing through the flap;
The determination unit moves the recording unit to the third position on the condition that the sheet detection unit detects that the trailing end of the sheet in the conveyance direction has been conveyed to the predetermined position. 9. The image recording apparatus according to any one of items 1 to 8.

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