JP2009126601A - Image recording device, side end position detection method of recording medium by the same device and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image recording device capable of detecting a side end position of a recording medium, even if the recording medium is difficult to obtain contrast, a side end position detection method of the recording medium by the device, and program. <P>SOLUTION: This image recording device 1 performs recording processing by discharging ink to the recording medium 31 from a recording head 13 having a plurality of nozzles in a process in which the recording medium 31 is conveyed in a conveying passage. A side end position detecting mechanism 6 is arranged on an upstream side of the recording head 13 in the conveying passage to detect detected information showing moving amount of an end part guide member 41 in contact with a side end of the recording medium 31 during conveyance when the guide member 41 is pushed by the side end. A side end position calculating part 17 calculates the side end position of the recording medium during the conveyance based on the detected information detected by the side end position detecting mechanism 6. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image recording technique for recording an image on a recording medium such as paper or film, and more particularly to a technique for detecting a side end position of the recording medium during image recording.

  As the image recording apparatus, for example, there is an ink jet type full line type color printer. In this printer, a recording head in which a plurality of nozzles for ejecting ink is formed is separated in the sub-scanning direction in a direction (main scanning direction) orthogonal to the transport direction (sub-scanning direction) in which the recording medium is transported. Thus, each ink color is arranged. In such an image recording apparatus (color printer), a recording medium for recording an image is disposed opposite to a plurality of nozzles in a recording head, and ink of each color is ejected from the plurality of nozzles to the recording medium, whereby characters and images are displayed. It is recorded.

  In such an image recording apparatus, when a recording medium is fed from a feeding unit such as a cassette or a tray, the fed recording medium may be displaced in the main scanning direction. When an image is recorded on the recording medium in this state, an image position shift in the main scanning direction occurs. In addition, when the deviation of the recording medium is large, image recording is performed on the outside of the recording medium, and the transport mechanism may be soiled. For this reason, the image recording apparatus needs to detect the side end (end in the main scanning direction) of the fed recording medium and adjust the image recording position based on the detection result.

As a technique for detecting a side edge of a recording medium, for example, an image forming apparatus and a side edge position detecting method of an image forming medium disclosed in Patent Document 1 are known.
According to the technique of Patent Document 1, the image sensor and the illumination unit are arranged on the upstream side of the transport mechanism unit. When the fed recording medium passes below the image sensor, the vicinity of the side edge of the recording medium is read by the image sensor. Then, according to the technique of Patent Document 1, the side end position is calculated based on the reading result in the vicinity of the side end, the range in which an image can be formed is specified based on the calculated side end position, Image formation is performed within the range.

As another technique related to this, for example, in Patent Document 2, the image forming position on the recording medium is shifted based on the detection result of the positional deviation in the main scanning direction of the recording medium being conveyed. A technique for preventing an image from protruding from a recording medium is disclosed.
JP 2006-44101 A Japanese Patent Laid-Open No. 2005-138489

  In the techniques of Patent Documents 1 and 2, the contrast is important when the vicinity of the side edge of the recording medium is read by the image sensor. For this reason, in the techniques of Patent Documents 1 and 2, it is necessary to change the belt color of the belt platen constituting the transport mechanism unit to a color different from that of the recording medium. For example, if the recording medium is white, the belt color in the belt platen needs to be not white, for example, black. As described above, in the techniques of Patent Documents 1 and 2, the color of the recording medium to be detected is limited by the belt color in the belt platen.

  Accordingly, the present invention has been made in view of the above-described problems, and an image recording apparatus capable of detecting the side edge position of a recording medium that is difficult to obtain a contrast, and a recording medium using the apparatus An object of the present invention is to provide a side edge position detection method and program.

  In order to achieve the above-described object, an image recording apparatus according to one aspect of the present invention ejects ink from a recording head having a plurality of nozzles to a recording medium in the course of the recording medium being conveyed along the conveyance path. In the image recording apparatus that performs the recording process, the end guide member that is disposed on the upstream side of the recording head in the transport path and contacts the side end of the recording medium being transported is pushed by the side end. A side end position detection mechanism that detects detection information indicating the amount of movement of the end guide member, and a side end that calculates the side end position of the recording medium being conveyed based on the detection information detected by the side end position detection mechanism And a position calculation unit.

  According to another aspect of the present invention, there is provided a recording medium side edge position detection method in which ink is ejected from a recording head having a plurality of nozzles to the recording medium while the recording medium is transported along a transport path. In this method, the side position of the recording medium is detected by the image recording apparatus that performs recording processing, and it is determined whether or not a predetermined time has elapsed since the detection of the recording medium that has started conveyance on the conveyance path. Detection information indicating the amount of movement of the end guide member when the end guide member disposed on the upstream side of the recording head and contacting the side end of the recording medium being conveyed is pushed by the side end. Reading of the detection information detected by the side end position detection mechanism to be detected is started when it is determined that a predetermined time has elapsed, and it is determined whether the calculation of the side end position based on the detection information has been performed a predetermined number of times. , Side edge If the calculation of the location is determined to have been performed for a predetermined number of times, thereby at least stores the calculated result of the side end position in the storage unit provided in the image recording apparatus, characterized in that.

  According to another aspect of the present invention, a program performs a recording process by discharging ink from a recording head having a plurality of nozzles to the recording medium in a process in which the recording medium is transported along the transport path. A program for causing an arithmetic processing unit to detect a side edge position of a recording medium by an image recording apparatus, and whether or not a predetermined time has elapsed since detection of a recording medium that has started conveyance on a conveyance path The end guide member disposed at the upstream side of the recording head in the transport path and contacting the side end of the recording medium being transported is pushed by the side end. Processing to start reading the detection information detected by the side end position detection mechanism that detects detection information indicating the movement amount when it is determined that a predetermined time has passed, and the side end position based on the detection information When determining whether the calculation has been performed a predetermined number of times, and when determining that the calculation of the side end position has been performed a predetermined number of times, the calculation result of the side end position is at least stored in a storage unit provided in the image recording apparatus. And processing to be stored in an arithmetic processing unit.

  According to the present invention, it is possible to provide an image recording apparatus capable of detecting the side edge position of a recording medium even if the recording medium is difficult to obtain a contrast, and a recording medium side edge position detecting method and program using the apparatus. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the following description, the conveyance direction of the recording medium is defined as the sub-scanning direction, and the direction orthogonal to the conveyance direction is defined as the main scanning direction.

First, a first embodiment of the present invention will be described.
FIG. 1 shows an image recording apparatus according to the first embodiment in a conceptual block configuration.
FIG. 2 shows an arrangement example of the feeding unit, the transport mechanism, the side end position detection mechanism, the image recording unit, and the collection unit of the image recording apparatus according to the present embodiment.

FIG. 3A is a top view of the side end position detection mechanism according to the first embodiment.
FIG. 3B is a cross-sectional view of the side end position detection mechanism according to the first embodiment.
First, the recording process of the image recording apparatus 1 according to the present embodiment will be described. The image recording apparatus 1 performs a recording process by ejecting ink from the recording head 13 having a plurality of nozzles to the recording medium 31 in the process in which the recording medium 31 is conveyed along the conveyance path.

  The image recording apparatus 1 includes a control unit 16, a feeding unit 2, a transport mechanism 3, a side end position detection mechanism 6 </ b> A in the side end position detection mechanism 6, an image recording unit 11, and a collection unit 15. Yes. Here, the control unit 16 controls the entire image recording apparatus 1. The feeding unit 2 feeds and transports the recording medium 31. The transport mechanism 3 transports the recording medium delivered from the feeding unit 2. The side edge position detection mechanism 6 </ b> A is provided upstream of the conveyance mechanism 3 in the conveyance path of the recording medium 31 and detects the side edge of the recording medium 31. The image recording unit 11 records an image on the recording medium 31. The collection unit 15 discharges and stores the recording medium 31 on which the image is recorded.

Next, each component of the image recording apparatus 1 will be further described.
The control unit 16 stores a processing circuit (not shown) composed of an MPU (micro processor unit) having a control function and a calculation function, and a control program, and sets setting values related to control of the device. It has a non-illustrated non-volatile memory that is stored and, for example, a RAM (Random Access Memory) that temporarily stores image recording information. The control unit 16 controls each component of the image recording apparatus 1 when the MPU reads the control program from the nonvolatile memory and executes it. At this time, the control unit 16 also functions as the side end position calculation unit 17 and the image recording control unit 19.

  Note that the control unit 16 causes the MPU to execute the control program so as to function as the side end position calculation unit 17, and as a signal processing circuit (hardware) controlled by the MPU, the side end position calculation unit 17 and the image recording unit. The control unit 19 may be configured and provided in the control unit 16.

  The feeding unit 2 contacts the feeding tray 2a for storing the sheet-like recording medium 31 and the uppermost recording medium 31 accommodated in the feeding tray 2a to take out one sheet at a time and receives it on the conveying mechanism 3 side. It includes a feeding drive unit 2b to be delivered and a feeding medium detection unit 2c that detects the fed recording medium 31.

  The feeding tray 2a is configured by a so-called feeding cassette or the like. The feeding drive unit 2b is constituted by a feeding roller, for example. The feeding medium detection unit 2c includes, for example, any one of an optical transmission sensor, an optical reflection sensor, a capacitance sensor, and the like, and detects, for example, the leading end of the recording medium 31 in the sub-scanning direction. To do.

  As shown in FIG. 2, the transport mechanism 3 is provided with the transport surface of the recording medium 31 facing the ink ejection ports of the plurality of recording heads 13. A drive roller 32 and a driven roller 33 are provided in the frame of the transport mechanism 3 so as to be separated from each other in the sub-scanning direction, and an endless transport belt 34 is rotatably mounted. The transport mechanism 3 includes a transport drive unit 4 connected to the rotation shaft of the drive roller 32, a transport information generation unit 5 connected to the rotation shaft of the driven roller 33, and at least one suction fan (not shown). Is provided.

  The conveyance information generation unit 5 includes, for example, a rotary encoder, generates a pulse signal as conveyance information accompanying the movement of the conveyance belt 34, and outputs the pulse signal to the control unit 16. A suction fan (not shown) generates a negative pressure according to an instruction from the control unit 16 and sucks the recording medium 31 onto the conveyance belt 34.

As shown in FIG. 2, the side end position detection mechanism 6 </ b> A is disposed between the feeding unit 2 and the conveyance mechanism 3, that is, on the upstream side of the recording head 13 in the conveyance path of the recording medium 31.
As shown in FIGS. 3A and 3B, the side end position detection mechanism 6A includes an end guide member 41, a lifting restriction member 42, a support member 43, a connecting member 44, a rotation detection unit 45, a connection member 46, and an elastic member. A member 47 is provided.

  The end guide member 41 is in contact with the side end of the recording medium 31 that is being transported along the transport path. The end guide member 41 is pushed by the side end when the recording medium 31 is further conveyed in the conveyance direction after contacting the side edge of the recording medium 31.

  The lifting restriction member 42 regulates the amount of lifting when the recording medium 31 comes into contact with the end guide member 41 and guides the recording medium 31 to be transported below a predetermined height from the transport surface of the transport path. .

The support member 43 has, for example, a bar shape, and supports the end guide member 41 via the connecting member 44.
The connecting member 44 connects the end guide member 41 and the support member 43 in a state where the end guide member 41 can be bent with respect to the support member 43 by a support point 44 a of the connection member 44.

The rotation detection unit 45 detects the rotation angle when the support member 43 is rotated from a predetermined position.
One end of the support member 43 is connected (axially supported) to the shaft of the rotation detection unit 45 by the connecting member 46, and rotates around this shaft. The support member 43 is connected to the end guide member 41 at the other end by a connecting member 44.

Accordingly, when the end guide member is pushed by the side end of the recording medium 31 being conveyed and moved, the support member 43 rotates around the axis of the rotation detection unit 45 in accordance with this movement.
The rotation detection unit 45 detects the rotation angle of the support member 43 that rotates according to the movement of the end guide member 41 as detection information that indicates the amount of movement of the end guide member 41. The rotation detection unit 45 is configured by, for example, a potentiometer, and outputs a voltage corresponding to the rotation angle of the shaft of the potentiometer to the control unit 16.

  The elastic member 47 is supported at a predetermined position parallel to the main scanning direction perpendicular to the conveyance direction of the recording medium 31 when the end guide member 41 is not pushed by the side end of the recording medium 31. Is maintained (maintained). As a result, when the support member 43 is separated from the end guide member 41 after the side end of the recording medium 31 being conveyed contacts and pushes the end guide member 41, the elastic member 47 becomes the end guide member 41. Is held (maintained) at a predetermined position before the contact.

As the elastic member 47, for example, a coil spring or a leaf spring can be used, but other elastic bodies such as rubber may be used.
The side end position detection mechanism 6 </ b> A is required to be smoothly moved by the pressing by the side end of the recording medium 31, and needs to be lightweight. For this reason, the end guide member 41 and the lifting restriction member 42 are made of a relatively lightweight member such as a resin. Further, the end guide member 41 and the lifting restriction member 42 are expected to be worn by contact with the recording medium 31. In order to reduce this wear, it is preferable to protect the contact surface with, for example, hard chrome plating.

  Note that the side end position detection mechanism 6A in FIGS. 3A and 3B shows a structure that is arranged on the left side with respect to the conveyance direction of the recording medium 31. FIG. The side end position detection mechanism 6 </ b> A is provided as a pair on both side ends of the recording medium 31. Therefore, the structure of the side end position detection mechanism 6A arranged on the right side with respect to the conveyance direction of the recording medium 31 has a symmetrical structure with respect to the illustrations of FIGS. 3A and 3B.

  Note that the contact surface of the end guide member 41 with which the side end of the recording medium 31 contacts is formed in a bow shape as viewed from above, as shown in FIG. 3A. By forming the contact surface of the end guide member 41 in this way, it becomes possible to receive the pushing force caused by the contact of the recording medium 31 even if the side end of the recording medium 31 is greatly displaced in the main scanning direction. The side edge of the recording medium 31 having various widths (lengths in the main scanning direction) can be detected.

The image recording unit 11 includes a recording head 13 and a recording head driving unit 12.
The recording head 13 is provided with a plurality of nozzles that eject ink linearly and over a length exceeding the recording medium 31 having the maximum width based on the design of the image recording apparatus 1. Recording is performed by ejecting ink droplets from the nozzles.

The recording head driving unit 12 outputs a driving signal for individually driving each nozzle of the recording head 13 to the recording head 13 by a control signal based on the recording data from the control unit 16.
The collection unit 15 includes, for example, a storage tray 15a, a discharge drive unit 15b, and a discharge medium detection unit 15c.

The storage tray 15a stores the discharged recording medium 31, and is constituted by a so-called collection tray or the like.
The discharge drive unit 15b discharges the recording medium 31 transported by the transport mechanism 3, and includes, for example, a pair of discharge rollers.

  The ejected medium detection unit 15c is configured by, for example, an optical transmission sensor, an optical reflective sensor, a capacitance sensor, or the like, and detects the rear end of the ejected recording medium 31. The discharged medium detection unit 15c may detect the tip of the recording medium 31 as necessary.

  The control unit 16 controls the feeding unit 2, the transport mechanism 3, the side end position detection mechanism 6 </ b> A, the image recording unit 11, and the collection unit 15, respectively, and performs a recording process on the recording medium 31. . The control unit 16 includes at least a side end position calculation unit 17, a storage unit 18, and an image recording control unit 19.

  The side edge position calculation unit 17 calculates the side edge position of the recording medium 31 in the transport path based on the detection information detected by the side edge position detection mechanism 6A. In the present embodiment, for example, the control unit 16 functions as the side end position calculation unit 17 by causing the MPU of the control unit 16 to read and execute a predetermined control program from the nonvolatile memory of the control unit 16.

The storage unit 18 is composed of, for example, a nonvolatile memory as a memory for temporarily storing designation information for recording processing including recording data.
The image recording control unit 19 performs control to correct the recording position when performing the recording process on the recording medium 31 based on the side end position of the recording medium 31 calculated by the side end position calculating unit 17. In the present embodiment, the control unit 16 functions as the image recording control unit 19 by causing the MPU of the control unit 16 to read and execute a predetermined control program from the nonvolatile memory of the control unit 16.

  The host device 21 is connected as an external device of the image recording apparatus 1 according to the present embodiment via, for example, a LAN (Local Area Network). The host apparatus 21 corresponds to a computer operated by a user who causes the image recording apparatus 1 according to the present embodiment to perform recording processing, and provides job information as information relating to recording processing to the image recording apparatus 1 according to the present embodiment. To be notified.

  The job information includes recording data when recording processing is performed on the recording medium 31, size designation information of the recording medium 31, and margin value designation information in the transport direction when recording processing is performed on the recording medium 31. , And designation information on the number of recording media 31 to be recorded. When the control unit 16 of the image recording apparatus 1 receives the job information notified from the host apparatus 21, the control unit 16 stores the job information in the storage unit 18 as recording processing (image recording) designation information.

Next, the conveyance operation and recording process of the recording medium 31 of the image recording apparatus 1 according to the present embodiment will be described in detail.
When receiving an instruction to start the recording process from the host device 21, the control unit 16 controls the transport driving unit 4 of the transport mechanism 3 to start the rotation of the transport belt 34. Next, the control unit 16 controls the feeding drive unit 2 b of the feeding unit 2 to pick up the recording media 31 stacked on the feeding tray 2 a one by one and deliver and transport them to the transport mechanism 3.

  The leading edge of the recording medium 31 conveyed in the conveyance path is detected by the feeding medium detection unit 2c disposed on the upstream side of the conveyance path by the side edge position detection mechanism 6A. The feeding medium detection unit 2 c outputs the detected edge signal to the control unit 16. Upon receiving this edge signal, the control unit 16 proceeds with the control process using the edge signal as a trigger signal for generating the recording process timing.

  Further, the transported recording medium 31 passes through the side end position detection mechanism 6A disposed on the upstream side of the transport mechanism 3, and the detection information described above is detected by the side end position detection mechanism 6A, and the control unit 16 Is output. Then, the side edge position calculation unit 17 calculates the side edge position of the recording medium 31 being conveyed based on this detection information.

The detection method of the detection information by the side end position detection mechanism 6A and the calculation method of the side end position of the recording medium 31 by the side end position calculation unit 17 will be described later.
The recording medium 31 that has passed through the side end position detection mechanism 6 </ b> A is adsorbed onto the conveyance belt 34 of the conveyance mechanism 3 as it is further conveyed downstream of the conveyance path.

  By the way, the pulse signal of the rotary encoder in the conveyance information generating unit 5 is conveyance information, but this signal is also used as a synchronization signal when recording processing is performed by the recording head 13. The control unit 16 stores in advance in the nonvolatile memory the timing for starting ink ejection from the nozzles by the recording head 13 as an accumulated value of the number of pulse signals. The control unit 16 controls the recording head driving unit 12 of the image recording unit 11 at a timing when the number of pulse signals coincides with the number of pulse signals of the rotary encoder generated by the conveyance information generation unit 5, and is placed on the conveyance belt 34. Ink is ejected from the nozzles of the recording head 13 to the adsorbed recording medium 31.

  Based on the recording processing designation information stored in the storage unit 18, the control unit 16 records the recording data for each line (1 line to k lines, k is an integer of 2 ≦ k) at the time of recording processing. Output to the control unit 19. In addition, the control unit 16 also outputs the side end position information of the recording medium 31 calculated by the side end position calculation unit 17 to the image recording control unit 19 in order to correct the image recording position in the main scanning direction. Accordingly, the image recording control unit 19 calculates a correction control condition for correcting the recording position for the recording data for each line and stores the correction control condition in the nonvolatile memory.

  This correction control condition is set for the recording head driving unit 12 when the recording head driving unit 12 controls the recording head 13 based on the recording data to perform the recording process. In this correction control condition, with respect to a plurality of nozzles of the recording head 13, setting of effective nozzles that perform ink ejection and invalid nozzles that do not perform ink ejection, or nozzles that are initially scheduled to eject ink are invalidated and other nozzles The setting for shifting the nozzles such as enabling is included.

  The control unit 16 controls image recording when the recording processing timing of the recording head 13 stored in advance in the nonvolatile memory (the accumulated value of the number of pulse signals described above) matches the number of pulse signals generated by the rotary encoder. The above-described correction control condition based on the side edge position information of the recording medium 31 associated with the recording data for each line calculated by the unit 19 is set in the recording head driving unit 12 and recording processing on the recording medium 31 is performed. Make it. Details will be described later.

  The recording medium 31 that has been subjected to the recording process in this manner is delivered to the collection unit 15 provided on the downstream side of the transport mechanism 3. Then, the recording medium 31 is nipped by the discharge driving unit 15b and further conveyed downstream in the conveyance path. Thereafter, the trailing edge of the recording medium 31 is detected by the discharge medium detection unit 15c and stored in the storage tray 15a.

Next, a detection information detection method by the side edge position detection mechanism 6A according to the present embodiment and a side edge position calculation method of the recording medium 31 by the side edge position calculation unit 17 will be described.
The side end position detection mechanism 6A is configured such that the recording medium 31 passes through the side end position detection mechanism 6A disposed on the upstream side of the transport mechanism 3 after the recording medium 31 is fed from the feeding unit 2. Detect side edges. Here, the timing at which the side edge position detection mechanism 6A detects the side edge of the recording medium 31 is, for example, when a predetermined time elapses after the leading edge of the recording medium 31 is edge-detected by the feeding medium detection unit 2c, or conveyed. It is assumed that the pulse signal generated by the rotary encoder pulse in the information generator 5 is input to the controller 16 a predetermined number of times.

FIG. 4A will be described. FIG. 4A shows a state in which the side edge position detection mechanism detects the side edge of the recording medium.
As shown in FIG. 4A, the side end position detection mechanism 6 </ b> A is provided as a pair on both side ends of the recording medium 31. Here, in FIG. 4A, the center position of the transport path is the ideal center position 35, and the center position of the transported recording medium 31 is the recording medium center position 36. In FIG. 4A, the separation distance (distance between the rotation axes of the support members 43) of the pair of side end position detection mechanisms 6A is W, and the medium width of the recording medium 31 (distance between both side ends) is Wp. Further, in FIG. 4A, the distance between the side edge position detection mechanism 6A and each side edge of the recording medium 31 is a left edge distance d ₁ and a right edge distance d ₂ , respectively. Is the center position deviation amount Δd.

As shown in FIG. 4A, the end guide members 41 of the pair of side end position detection mechanisms 6A are respectively pressed against both side ends of the recording medium 31 being conveyed, and the width Wp of the recording medium 31 The end guide member 41 is moved in accordance with the displacement of the recording medium 31 in the main scanning direction. At this time, the support members 43 of the pair of side end position detection mechanisms 6A are rotated by the angles θ ₁ and θ _{2 with} respect to the main scanning direction in conjunction with the movement of the end guide member 41, respectively. The rotation detector 45 outputs voltage values corresponding to the rotation angles θ ₁ and θ ₂ and notifies the controller 16 of the voltage values.

The side end position calculation unit 17 of the control unit 16 obtains the rotation angles θ ₁ and θ ₂ corresponding to the voltage values from the notified voltage values. Note that a non-illustrated non-volatile memory of the control unit 16 stores in advance a table indicating the correspondence between the voltage value output from the rotation detection unit 45 and the rotation angle. Thereby, the side end position calculation unit 17 of the control unit 16 can obtain the rotation angles θ ₁ and θ ₂ corresponding to the notified voltage value by referring to the table. For example, if each rotation angle to be obtained is a function of a voltage value, the side end position calculation unit 17 of the control unit 16 obtains each rotation angle θ ₁ and θ ₂ by calculation instead of referring to the table. It is also possible.

Next, the side end position calculation unit 17 calculates the left end distance d ₁ and the right end distance d ₂ based on the obtained rotation angles θ ₁ and θ ₂ .
Here, FIG. 4B will be described. FIG. 4B schematically shows the side end position detection mechanism disposed on the left side in the transport direction of the pair of side end position detection mechanisms. Note that, as described above, the side end position detection mechanism 6A disposed on the right side with respect to the transport direction among the pair of side end position detection mechanisms 6A is a diagram in which the schematic diagram shown in FIG. Become.

In Figure 4B, the distance from the connecting member 44 (supporting point 44a) to the connection member 46 and X _1. Further, in FIG. 4B, the distance from the connecting member 44 to the side edge of the recording medium 31 and X _2. In the description here, the values of X ₁ and X ₂ are the same for both the pair of side end position detection mechanisms 6A. These values are stored in advance in a nonvolatile memory (not shown) of the control unit 16.

Here, it is assumed that the support member 43 is rotated by an angle θ with respect to the main scanning direction. At this time, the distance (end distance) d to the axis X ₀ when the support members 43 spaced apart in the main scanning direction is rotated from the side end portion 41a of the recording medium 31, by the following equation (1) Can be represented.

d = X ₁ cos θ + X ₂ (1)
That is, as represented by the equation (1), the end distance d is calculated by adding the distance X ₂ to the value obtained by multiplying the distance X ₁ by the cosine value of the rotation angle of the support member 43. can do.

When d in the equation (1) is replaced with d ₁ and d ₂ and θ is replaced with θ ₁ and θ ₂ , respectively, the left end distance d ₁ and the right end distance d ₂ are expressed by the following (2 ) And (3).

d ₁ = X ₁ cos θ ₁ + X ₂ (2)
d ₂ = X ₁ cos θ ₂ + X ₂ (3)
Side edge position calculating section 17, by performing the expression (2) and (3) calculation, based on the rotational angle theta ₁ and theta _2, the left end portion a distance d ₁ and the right end portion a distance d ₂ And the calculation result is stored in a non-volatile memory (not shown).

  Note that the number of times that the side edge position detection mechanism 6A detects the side edge of the recording medium 31 may be one, but in order to obtain a stable result, it may be detected a plurality of times at a predetermined timing. Here, when the detection is performed a plurality of times, for example, an average value thereof is calculated, and the calculation result is stored in a storage unit (not shown).

Thereafter, the image recording control unit 19 records on the recording medium 31 on the basis of the both end positions (the left end distance d ₁ and the right end distance d ₂ ) of the recording medium 31 calculated by the side end position calculating section 17. A correction control condition for the recording head drive unit 12 for correcting the recording position when performing the process is calculated. As a method for changing the recording position based on the correction control condition, for example, a known method described in Patent Document 2 is adopted. This known method will be briefly described. The amount of deviation of the recording medium center position 36 being conveyed with respect to the reference center position (that is, the ideal center position 35 in FIG. 4A) in image recording by the recording head 13 (that is, Δd in FIG. 4A). This is a method of shifting the center position address of the ink nozzle row in the recording head 13 based on the above.

Note that the center position deviation amount Δd of the recording medium 31 can be calculated as follows, for example.
First, it is apparent from FIG. 4A that the paper width Wp and the center position deviation amount Δd of the recording medium 31 can be expressed by the following equations.

Wp = W− (d ₁ + d ₂ ) (4)
Δd = (d ₁ + Wp / 2) −W / 2 (5)
Substituting this equation (4) into equation (5),
Δd = (d ₁ −d ₂ ) / 2 (6)
It becomes. By substituting the above-described equations (2) and (3) into this equation (6), the center position deviation amount Δd can be expressed by the following equation.

Δd = X ₁ (cos θ ₁ −cos θ ₂ ) / 2 (7)
That is, the center position deviation amount Δd of the recording medium 31 is a support member in each of the side end position detection mechanisms 6A disposed as a pair at both ends of the recording medium 31, as represented by the equation (7). It can be calculated by multiplying the difference value about the cosine value of the rotation angle of 43 by a value of ½ of the distance X ₁ .

Next, FIG. 5 will be described. FIG. 5 is a flowchart showing the processing contents of the control processing performed by the control unit for calculating the side end position in the first embodiment.
The processing shown in FIG. 5 is realized by the MPU reading and executing a control program stored in advance in a non-illustrated non-volatile memory of the control unit 16. The control unit 16 functions as the side end position calculation unit 17 when the MPU executes this control program.

When the control unit 16 receives the job information notified from the host device 21, the control unit 16 starts the control process of FIG.
First, in step Sa1, the control unit 16 performs processing for instructing the feeding unit 2 to feed the recording medium 31. Receiving this instruction, the feeding unit 2 starts feeding the recording medium 31.

  Next, in step Sa2, the control unit 16 receives from the feeding medium detection unit 2c an edge signal indicating that the time since the feeding of the recording medium 31 is started, that is, the leading edge of the recording medium 31 is detected. A process for determining whether or not a predetermined time has passed has been performed. Here, when it is determined that the predetermined time has elapsed (when the determination result is YES), the control unit 16 moves the process to step Sa3. On the other hand, when it is determined that the predetermined time has not yet elapsed (when the determination result is NO), the control unit 16 moves the process to step Sa2 and repeats this determination process.

  Next, in step Sa3, the control unit 16 reads the above-described detection information detected by each of the pair of side end position detection mechanisms 6A, and based on the obtained detection information, the above-described equation (2) and By calculating the expression (3), a process for calculating a separation distance corresponding to the both end positions of the recording medium 31 being conveyed is performed.

  Next, in step Sa4, the control unit 16 performs a process of determining whether or not the calculation of the both end positions has been performed a predetermined number of times. Here, when it is determined that the calculation of the both end positions has been performed the predetermined number of times (when the determination result is YES), the control unit 16 shifts the processing to step Sa5. On the other hand, when it is determined that the calculation of the both end positions has not been performed up to the predetermined number of times (when the determination result is NO), the control unit 16 moves the process to step Sa3 and repeats the calculation process of the both end positions.

  Next, in step Sa5, the control unit 16 stores the average value of the side end positions (separation distance) calculated a predetermined number of times in a non-illustrated non-volatile memory as the final calculation result of the both end positions of the recording medium 31. After that, the control process is terminated.

  As described above, according to the first embodiment of the present invention, the end guide member 41 is brought into contact with the side end of the recording medium 31 to detect the position of the side end of the recording medium 31. The side edge of the recording medium 31 can be appropriately detected without being affected by the contrast with the conveyance belt 34. Further, according to the first embodiment of the present invention, since the lifting restriction member 42 is provided on the end guide member 41, the recording medium 31 that can be generated when the recording medium 31 contacts the end guide member 41. By restricting the floating, jamming (clogging) of the recording medium 31 can be prevented.

  Next, a second embodiment of the present invention will be described. In the description of the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and only the portions different from those in the first embodiment are shown and described here.

  In the first embodiment of the present invention described above, the side end position detection mechanism 6A is fixed at the position of the rotation detection unit 45 (the position of the shaft when the support member 43 is rotated). Here, for example, it is assumed that the side edge position detection mechanism 6A is fixed at a position where the side edge can be easily detected when an A3 size sheet is the recording medium 31. Then, in this case, the side edge position detection mechanism 6A detects the side edge when the recording medium 31 has an extremely narrow width (length in the main scanning direction) than the A3 size. It is assumed that shifting or side edge detection is not possible.

  In view of this point, the second embodiment has a configuration in which the position of the side end position detection mechanism 6B in the side end position detection mechanism 6 can be moved in the main scanning direction, so that the width of the recording medium 31 is remarkably increased. Make sure that the side edges can be detected even when they are different.

FIG. 6 shows a conceptual block configuration of an image recording apparatus according to the second embodiment.
In the configuration shown in FIG. 6, the side end position detection mechanism 6A according to the first embodiment is replaced with a side end position detection mechanism 6B to which a side end position detection mechanism drive unit 7 and a drive position detection unit 8 are added. ing.

In addition, the example of arrangement | positioning of each component of the image recording device which concerns on this 2nd embodiment is shown in FIG. 2 similarly to what concerns on 1st embodiment.
7A and 7B are top views of the side end position detection mechanism according to the second embodiment.

  The side end position detection mechanism 6B shown in FIGS. 7A and 7B is different from the side end position detection mechanism 6A according to the first embodiment shown in FIG. 3A in the detection mechanism drive unit 7, the drive position detection unit 8, and the movement guide. 48 and a movable pedestal 49 are added. Note that the side end position detection mechanism 6B is disposed in a pair at both ends of the recording medium 31 in the same manner as the side end position detection mechanism 6A according to the first embodiment.

The detection mechanism drive unit 7 is constituted by, for example, a pulse motor.
The moving pedestal 49 is moved in the main scanning direction on the moving guide 48 by the detection mechanism driving unit 7. 7A and 7B show a case where the side end position detection mechanisms 6B are arranged at different positions due to the movement of the moving base 49 by the detection mechanism driving unit 7. FIG.

  A rotation detector 45 to which the support member 43 is connected is mounted on the moving base 49. Therefore, when the side end position detection mechanism 6B moves the movable base 49 to a predetermined distance, the position of the shaft when the support member 43 is rotated and the end guide member 41 supported by the support member 43 are detected. The position can be changed to a predetermined position separated in the main scanning direction.

  The drive position detection unit 8 includes, for example, any one of an optical transmission sensor, an optical reflection sensor, a capacitance sensor, and the like. The drive position detection unit 8 detects a moving base 49 that the detection mechanism driving unit 7 moves on the movement guide 48 in the main scanning direction.

  As described above, the side end position detection mechanism 6B includes the detection mechanism drive unit 7 as a detection mechanism drive unit that moves the side end position detection mechanism 6B itself in a direction orthogonal to the conveyance direction of the conveyance path of the recording medium 31. .

Next, a detection information detection method by the side end position detection mechanism 6B according to the second embodiment and a side end position calculation method of the recording medium 31 by the side end position calculation unit 17 will be described.
When the control unit 16 of the image recording apparatus 1 receives the job information notified from the host apparatus 21, the control unit 16 first stores the job information in the storage unit 18 as image recording information.

  Next, the control unit 16 drives the detection mechanism driving unit 7 of the side end position detection mechanism 6B to move the moving base 49 to a position that can be detected by the driving position detecting unit 8, and then moves the moving base 49. Is moved to a position that is preset based on the size information of the recording medium 31 included in the job information and is optimal for detecting the side edge of the recording medium 31. Here, the control unit 16 corresponds to the movement distance from the detection position in the drive position detection unit 8 to the pulse motor in the detection mechanism drive unit 7 on the basis of the detection signal of the moving base 49 by the drive position detection unit 8. By driving the predetermined number of pulses, the movable pedestal 49 is arranged at the optimum position. The storage unit 18 (not shown) of the control unit 16 stores information on the size of the recording medium 31 and the optimal position of the moving base 49 (that is, the axis when the support member 43 in the side end position detection mechanism 6B is rotated). It is stored in advance as a table indicating the correspondence relationship with (optimum position). The control unit 16 obtains the optimum position of the moving base 49 according to the size of the recording medium 31 by referring to the table.

The control unit 16 controls the feeding unit 2 to feed the recording medium 31 after the change of the position of the side end position detection mechanism 6B is completed by the movement of the moving base 49.
Since the second embodiment is the same as the first embodiment in the subsequent method for detecting the side edge of the recording medium 31, the description thereof will be omitted.

  Next, FIGS. 8 and 9 will be described. FIG. 8 is a flowchart showing the contents of the control process performed by the control unit for calculating the side edge position in the second embodiment. FIG. 9 is a flowchart showing the processing contents of a subroutine in the control processing shown in FIG.

  The processing shown in FIGS. 8 and 9 is realized by the MPU reading and executing a control program stored in advance in a nonvolatile memory (not shown) of the control unit 16. The control unit 16 functions as the side end position calculation unit 17 when the MPU executes this control program.

  When the control unit 16 receives the job information notified from the host device 21, the control unit 16 starts the control process of FIG. First, in step Sb1, the control unit 16 shifts the processing to the subroutine of FIG.

Next, in step Sc <b> 1, the control unit 16 performs a process of acquiring the size information of the recording medium 31 included in the job information notified from the host device 21.
Next, in step Sc2, the control unit 16 controls the detection mechanism driving unit 7 to move the side edge position detection mechanism 6B, and the size of the recording medium 31 indicated by the job information notified from the host device 21. Based on the information, a process of changing the position of the side end position detection mechanism 6B is performed.

  Next, in Step Sc3, the control unit 16 performs a process of determining whether or not the side end position detection mechanism 6B has been moved to a predetermined position optimal for detecting the side end of the recording medium 31. Here, when the control unit 16 determines that the movement of the side end position detection mechanism 6B is completed (when the determination result is YES), the control unit 16 ends the processing of the subroutine shown in FIG. 9 and proceeds to step Sb2 of FIG. Move processing. On the other hand, when it is determined that the movement of the side edge position detection mechanism 6B has not yet been completed (when the determination result is NO), the control unit 16 moves the process to step Sc3 and repeats this determination process.

Next, in step Sb2, the control unit 16 performs processing for instructing the feeding unit 2 to feed the recording medium 31. Receiving this instruction, the feeding unit 2 starts feeding the recording medium 31.
Next, in step Sb3, the control unit 16 receives from the feeding medium detection unit 2c the time since the feeding of the recording medium 31 was started, that is, an edge signal indicating that the leading edge of the recording medium 31 has been detected. A process for determining whether or not a predetermined time has passed has been performed. Here, when it is determined that the predetermined time has elapsed (when the determination result is YES), the control unit 16 shifts the processing to step Sb4. On the other hand, when it is determined that the predetermined time has not yet elapsed (when the determination result is NO), the control unit 16 moves the process to step Sb3 and repeats this determination process.

  Next, in step Sb4, the control unit 16 reads the detection information detected by each of the pair of side end position detection mechanisms 6B, and based on the obtained detection information, the above-described equation (2) and By calculating the expression (3), the above-described separation distance corresponding to the both end positions of the recording medium 31 being conveyed is calculated.

  Next, in step Sb5, the control unit 16 performs a process of determining whether or not the calculation of the both end positions has been performed a predetermined number of times. Here, when it is determined that the calculation of the both end positions has been performed the predetermined number of times (when the determination result is YES), the control unit 16 moves the process to step Sb6. On the other hand, when it is determined that the calculation of the both end positions has not been performed up to the predetermined number of times (when the determination result is NO), the control unit 16 moves the process to step Sb4 and repeats the calculation process of the both end positions.

  Next, in step Sb6, the control unit 16 stores the average value of the side end positions (separation distance) calculated a predetermined number of times in a storage unit (not shown) as the final calculation result of the both side end positions of the recording medium 31. Processing is performed, and thereafter, this control processing is terminated.

  As described above, according to the second embodiment of the present invention, the end guide member 41 that contacts the side end of the recording medium 31 is moved according to the width of the recording medium 31 in order to detect the side end position. After that, the side edge of the recording medium 31 is detected. Thereby, in addition to the effect of the first embodiment, the second embodiment of the present invention is used when the size (width) of the recording medium 31 to be conveyed is greatly different, such as an A3 size paper and a public postcard. In addition, the side end position of the recording medium 31 can be detected appropriately.

Next, a modification of the first or second embodiment of the present invention described above will be described.
FIG. 10 is a view of a modification of the side end position detection mechanism according to the first or second embodiment as seen from the main scanning direction.

  In the side end position detection mechanism 6A or 6B shown in FIG. 10, the lifting restriction member 42 is formed in a curved shape along the conveyance direction of the recording medium 31. The curved shape is formed such that the downstream side of the conveyance path is lower than the upstream side at the height from the conveyance surface of the conveyance path of the recording medium 31 to the lifting regulating member 42.

  In the lifting restriction member 42 in the side end position detection mechanisms 6A and 6B in the first or second embodiment, the recording medium 31 is formed linearly along the transport direction. In such a linear formation, the recording medium 31 does not rise above the predetermined height by the lifting restriction member 42, but may rise between the conveyance surface and the lifting restriction member 42. In the lift regulation member 42 formed in a straight line, when the recording medium 31 with such lift is transported to the downstream side, the side end position detection mechanisms 6A and 6B or the transport mechanism 3 can prevent the recording medium 31 from moving. Jam (clogging) may occur.

  On the other hand, the lift control member 42 of the modified example has a curved shape as shown in FIG. 10 so that the distance between the transport surface and the lift control member 42 becomes narrower toward the downstream side of the transport path. Therefore, in the process in which the recording medium 31 is conveyed by the side edge position detection mechanism 6A or 6B, the floating is suppressed. As a result, the occurrence of jamming of the recording medium 31 can be reduced in the lift regulating member 42 of the modified example.

  Note that the height of the lift regulating member 42 on the downstream side in the conveyance direction of the modified example is, for example, the surface of the corrugated paper having the maximum thickness among the types of the recording medium 31 conveyed on the conveyance surface. It is preferable to set the lower surface of the substrate to a height that ensures a slight gap.

  Further, the side end position detection mechanism 6A or 6B shown in FIG. 10 has the lifting restriction member 42 formed in a curved shape, but any other shape can be used as long as the leading end portion of the recording medium 31 being conveyed is not easily caught. The shape may be acceptable.

  The present invention can form various embodiments by appropriately combining a plurality of components disclosed in each of the first or second embodiment and the modified examples. For example, some constituent elements may be deleted from the overall configuration shown in the first or second embodiment, or constituent elements in different embodiments may be appropriately combined.

  In addition, the embodiment of the present invention is not limited to the first or second embodiment and the modified examples, and can be embodied by modifying the components without departing from the necessity in the implementation stage.

1 is a diagram illustrating a conceptual block configuration of an image recording apparatus according to a first embodiment. It is a figure which shows the example of arrangement | positioning of the feeding part of the image recording apparatus which concerns on this embodiment, a conveyance mechanism, a side edge position detection mechanism, an image recording part, and a collection | recovery part. It is a top view of the side end position detection mechanism according to the first embodiment. It is sectional drawing of the side end position detection mechanism which concerns on 1st embodiment. FIG. 6 is a diagram illustrating a state in which a side end position detection mechanism detects a side end of a recording medium. It is the figure which showed typically the left side edge position detection mechanism with respect to the conveyance direction among a pair of side edge position detection mechanisms. It is the figure which showed the processing content of the control processing which a control part performs for calculation of a side edge position in 1st embodiment with the flowchart. It is a figure which shows the conceptual block structure of the image recording apparatus which concerns on 2nd embodiment. It is a top view (the 1) of the side end position detection mechanism concerning a second embodiment. It is a top view (the 2) of the side end position detection mechanism concerning a second embodiment. It is the figure which showed the processing content of the control processing which a control part performs for calculation of a side end position in 2nd embodiment with the flowchart. It is the figure which showed the processing content of the subroutine in the control processing shown by FIG. 8 with the flowchart. It is the figure which looked at the modification of the side edge position detection mechanism which concerns on 1st or 2nd embodiment from the main scanning direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording apparatus 2 Feeding part 2a Feeding tray 2b Feeding drive part 2c Feeding medium detection part 3 Conveyance mechanism 4 Conveyance drive part 5 Conveyance information generation part 6 (6A, 6B) Side edge position detection mechanism 7 Detection mechanism drive Unit 8 drive position detection unit 11 image recording unit 12 recording head drive unit 13 recording head 15 collection unit 15a storage tray 15b discharge drive unit 15c discharge medium detection unit 16 control unit 17 side end position calculation unit 18 storage unit 19 image recording control unit 21 Host Device 31 Recording Medium 32 Drive Roller 33 Driven Roller 34 Conveying Belt 35 Ideal Center Position 36 Recording Medium Center Position 41 End Guide Member 42 Lifting Restriction Member 43 Support Member 44 Connection Member 44a Support Point 45 Rotation Detection Unit 46 Connection Member 47 Elastic member 48 Movement guide 49 Movement base

Claims (14)

In an image recording apparatus that performs a recording process by ejecting ink from a recording head having a plurality of nozzles to the recording medium in a process in which the recording medium is conveyed along the conveyance path.
The amount of movement of the end guide member when the end guide member disposed on the upstream side of the recording head in the transport path and in contact with the side end of the recording medium being transported is pushed by the side end. A side end position detection mechanism for detecting detection information indicating
An image recording apparatus comprising at least a side end position calculation unit that calculates a side end position of the recording medium being conveyed based on detection information detected by the side end position detection mechanism. The side end position detection mechanism has a support member that supports the end guide member,
When the end guide member is moved by the pushing by the side end of the recording medium, the support member rotates according to the movement around the shaft that pivotally supports the support member,
The image recording apparatus according to claim 1, wherein the side end position detection mechanism detects a rotation angle of the support member as the detection information. In the support member, when the end guide member is not pushed by the side edge of the recording medium, the direction in which the support point of the end guide member and the shaft are connected in a straight line is the transport of the transport path. Is held at a position perpendicular to the direction,
The side end position calculation unit calculates a cosine value of a rotation angle of the support member with respect to a distance between the support point and the shaft when the support member is rotated by the pushing by the side end of the recording medium. The side edge position of the recording medium is calculated by adding the shortest distance from the support point to the contact surface of the side edge of the recording medium at the end guide member to the multiplied value. The image recording apparatus according to claim 2.   The side end position detection mechanism includes an elastic body that returns the guide member when the side end of the recording medium being conveyed comes out after contact to the predetermined position before the side end of the recording medium comes into contact. The image recording apparatus according to claim 1.   The side edge position detection mechanism guides the recording medium so that the recording medium is conveyed below the predetermined height from the conveyance surface of the conveyance path when the side edge of the recording medium being conveyed contacts the guide member. The image recording apparatus according to claim 1, further comprising a lifting restriction member.   The lift control member further guides the recording medium so as to approach the transport surface side of the transport path in the process of transporting the recording medium to the downstream side of the transport path. 5. The image recording apparatus according to 5.   2. The image according to claim 1, wherein the side end position detection mechanism further includes a detection mechanism driving unit that moves the side end position detection mechanism itself in a direction orthogonal to a transport direction of the transport path. Recording device.   The image recording apparatus according to any one of claims 1 to 7, wherein the side edge position detection mechanism is disposed in a pair when detecting both side edges of the recording medium. A control unit including at least the side end position calculation unit;
The control unit is configured to include at least an arithmetic processing unit and a storage unit in which a control program to be executed by the arithmetic processing device is stored in advance, and by causing the arithmetic processing unit to execute the control program, the control unit The image recording apparatus according to claim 1, wherein the image recording apparatus functions as a side end position calculation unit.   The control unit further includes an image recording control unit that corrects a recording position when performing the recording process on the recording medium based on the side end position of the recording medium calculated by the side end position calculating unit. The image recording apparatus according to claim 9. A method for detecting a side edge position of the recording medium by an image recording apparatus that performs recording processing by discharging ink from a recording head having a plurality of nozzles to the recording medium in a process in which the recording medium is transported along a transport path,
Determining whether or not a predetermined time has elapsed since the detection of the recording medium on which conveyance in the conveyance path was started,
The amount of movement of the end guide member when the end guide member disposed on the upstream side of the recording head in the transport path and in contact with the side end of the recording medium being transported is pushed by the side end. Reading of the detection information detected by the side edge position detection mechanism for detecting the detection information indicating that, when it is determined that the predetermined time has elapsed,
Determine whether the calculation of the side edge position based on the detection information has been performed a predetermined number of times,
When it is determined that the calculation of the side end position has been performed a predetermined number of times, the calculation result of the side end position is stored at least in a storage unit provided in the image recording apparatus. Edge position detection method.   The position of the side edge position detection mechanism disposed in the transport path is further changed based on the size information of the recording medium indicated in the job information notified from the external device. The method for detecting a side edge position of a recording medium according to claim 11. An arithmetic processing unit that detects the side edge position of the recording medium by an image recording apparatus that performs recording processing by ejecting ink from the recording head having a plurality of nozzles to the recording medium in a process in which the recording medium is conveyed along the conveyance path Is a program for letting
A process for determining whether or not a predetermined time has elapsed since the detection of the recording medium on which conveyance in the conveyance path has started;
The amount of movement of the end guide member when the end guide member disposed on the upstream side of the recording head in the transport path and in contact with the side end of the recording medium being transported is pushed by the side end. A process of starting the reading of the detection information detected by the side end position detection mechanism for detecting the detection information indicating that the predetermined time has elapsed,
A process of determining whether the calculation of the side end position based on the detection information has been performed a predetermined number of times;
When it is determined that the calculation of the side end position has been performed a predetermined number of times, the calculation processing device performs at least a process of storing the calculation result of the side end position in a storage unit provided in the image recording apparatus. A program characterized by   Processing for changing the position of the side end position detection mechanism disposed in the transport path based on the size information of the recording medium indicated in the job information notified from the external device is the arithmetic processing unit. The program according to claim 13, further executed.