Recording device

Abstract

To solve a problem that reduction of received light intensity of reflection light caused by dirt on a reference member may prevent accurate setting of a gap between a print head and a guide frame in a structure in which the gap is detected with an optical sensor.SOLUTION: A recording device includes: a recording part which may move forward or rearward relative to a transport path; a facing part which is disposed facing the recording part; a motor serving as a power source which causes the recording part to move; and moving means which receives the power of the motor to move the recording part. The moving direction of the recording part includes a vertical direction component. Position detecting means for detecting a position of the recording part relative to the transport path is a linear encoder including: a linear scale provided along the moving direction of the recording part; and a first detection part which is provided at the recording part and detects the linear scale. The moving means has a structure which allows idling of the motor after the recording part utilizes the self-weight to be placed on the facing part when the moving means moves the recording part downward to the facing part.SELECTED DRAWING: Figure 19

Description

Technical Field

[0001] The present invention relates to a recording apparatus that records on a medium.

Background Art

[0002] The printer described in Patent Document 1 includes a guide frame that guides printing paper, a print head held by a carrier that moves above the guide frame, and an alignment sensor provided on the carrier. The guide frame is raised and lowered according to the thickness of the printing paper. When the alignment sensor moves above the reference member, the cover slides and the reference member is exposed. The alignment sensor irradiates light on the reference member and receives the reflected light from the reference member, and outputs a light reception signal according to the light reception intensity. The printer described in Patent Document 1 detects the height position of the guide frame based on the above light reception signal, that is, detects the gap between the print head and the guide frame.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration of detecting the gap between the print head and the guide frame by irradiating light on the reference member and receiving the reflected light from the reference member as described above, there is a possibility that the light reception intensity of the reflected light decreases due to contamination of the reference member. Since this decrease in light reception intensity directly affects the detection accuracy of the gap between the print head and the guide frame, there is a possibility that the gap cannot be accurately set.

Means for Solving the Problems

[0005] To solve the above problems, the recording apparatus of the present invention includes a conveyance path for conveying a medium, a recording unit for performing recording on the medium, the recording unit being movable in a direction advancing and retreating with respect to the conveyance path, an opposing unit disposed opposite to the recording unit, a motor which is a power source for moving the recording unit, moving means for moving the recording unit by receiving the power of the motor, position detection means for detecting the position of the recording unit with respect to the conveyance path, and a control unit for controlling the motor. The moving direction of the recording unit includes a vertical direction component. The position detection means is a linear encoder including a linear scale provided along the moving direction of the recording unit and a first detection unit provided on the recording unit for detecting the linear scale. The moving means has a configuration that allows the motor to idle after the recording unit has landed on the opposing unit by utilizing its own weight when the recording unit is lowered toward the opposing unit. The control unit grasps the position of the recording unit in the moving direction based on a change in the detection signal of the position detection means when the recording unit lands on the opposing unit or a change in the detection signal of the position detection means when the recording unit rises from the state of being on the opposing unit.

Brief Description of the Drawings

[0006]

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Embodiments for Carrying Out the Invention

[0007] Hereinafter, the present invention will be schematically described. The recording apparatus according to the first aspect includes a conveyance path for conveying a medium, a recording unit that performs recording on the medium, the recording unit being movable in a direction advancing and retreating with respect to the conveyance path, an opposing unit disposed opposite to the recording unit, a motor that is a power source for moving the recording unit, moving means that receives the power of the motor and moves the recording unit, position detection means for detecting the position of the recording unit with respect to the conveyance path, and a control unit that controls the motor. The moving direction of the recording unit includes a vertical direction component. The position detection means is a linear encoder including a linear scale provided along the moving direction of the recording unit and a first detection unit provided on the recording unit for detecting the linear scale. The moving means has a configuration that allows the motor to idle after the recording unit has landed on the opposing unit using its own weight when the recording unit is lowered toward the opposing unit. The control unit grasps the position of the recording unit in the moving direction based on a change in the detection signal of the position detection means when the recording unit lands on the opposing unit or a change in the detection signal of the position detection means when the recording unit rises from the state of having landed on the opposing unit.

[0008] According to this aspect, when the recording unit is placed on the opposing part, the control unit grasps the position of the recording unit in the moving direction based on the change in the detection signal of the position detection means, or the change in the detection signal of the position detection means when the recording unit rises from the state of being placed on the opposing part. Therefore, the position of the recording unit relative to the opposing part can be appropriately grasped, and thus the gap between the recording unit and the opposing part can be appropriately set.

[0009] In addition, when the moving means lowers the recording unit toward the opposing part, since the moving means has a configuration that allows the motor to idle after the recording unit has been placed on the opposing part using its own weight, the following operational effects can be obtained. For example, in the case of a configuration where the position of the recording unit in the moving direction is grasped by detecting an increase in the drive current value of the motor when the recording unit abuts against the opposing part, a load is applied to the moving means, which may cause damage to the components. Also, if the moving means includes a worm gear mechanism, there is a risk of excessive surface pressure occurring between the worm wheel and the cylindrical worm, resulting in locking. However, in this aspect, as described above, when the moving means lowers the recording unit toward the opposing part, since the moving means has a configuration that allows the motor to idle after the recording unit has been placed on the opposing part using its own weight, the occurrence of the above-mentioned problems can be suppressed. Note that the idling of the motor means a state in which the rotation of the motor is not converted into the movement of the recording unit and the motor does not receive a load from the recording unit. Also, in this specification, the recording unit being placed on the opposing part using its own weight does not mean only the form in which the recording unit is placed on the opposing part only by its own weight, but also includes the form in which the recording unit is placed on the opposing part while receiving a pressing force in a direction including a vertically downward component from a spring or the like in addition to its own weight.

[0010] The second aspect is an aspect dependent on the first aspect, and is characterized in that it includes rotation detection means for detecting the rotation of the motor, and the control unit grasps the position of the recording unit in the moving direction based on the detection signal of the position detection means and the detection signal of the rotation detection means.

[0011] According to this aspect, since the control unit grasps the position of the recording unit in the moving direction based on the detection signal of the position detection means and the detection signal of the rotation detection means, the position of the recording unit in the moving direction can be accurately grasped.

[0012] A third aspect is an aspect dependent on the second aspect, wherein the rotation detection means is a rotary encoder including a rotary scale provided on the output shaft of the motor and a second detection unit that detects the rotary scale.

[0013] According to this aspect, since the rotation detection means includes a rotary scale provided on the output shaft of the motor and a second detection unit that detects the rotary scale, the rotation of the motor can be accurately detected.

[0014] A fourth aspect is an aspect dependent on the third aspect, wherein the moving means includes a cylindrical worm driven by the motor and a worm wheel that meshes with the cylindrical worm and rotates as the cylindrical worm rotates.

[0015] Since the moving means includes a worm gear mechanism, there is a risk of locking if excessive surface pressure occurs between the worm wheel and the cylindrical worm. However, due to the operation and effect of the first aspect described above, an excessive load is not applied to the moving means when grasping the position of the recording unit with respect to the opposing portion, so the occurrence of the above locking can be suppressed. In addition, the worm gear mechanism can increase the reduction ratio when transmitting power from the motor to the recording unit. As a result, the resolution of the rotary encoder can be made higher than the resolution of the linear encoder, and the recording unit can be accurately positioned with respect to the opposing portion. The resolution, moreover, means the number of pulses output with respect to the unit operation amount. For example, in the case of the resolution of the rotary encoder, it is the number of pulses output with respect to one rotation of the output shaft of the motor. Also, in the case of the resolution of the linear encoder, it is the number of pulses output with respect to the unit movement amount of the recording unit.

[0016] A fifth aspect is an aspect dependent on the first aspect, wherein when the control unit lowers the recording unit toward the opposing unit, the control unit determines the position of the recording unit at the time when the signal change of the linear encoder disappears during the rotation of the motor, or when the recording unit rises from the state of being placed on the opposing unit, the control unit determines the position of the recording unit at the time when the signal change of the linear encoder occurs during the rotation of the motor, and sets the origin position of the recording unit in the moving direction based thereon.

[0017] According to this aspect, the origin in the moving direction of the recording unit can be appropriately set using the signal change of the linear encoder. As a result, the positioning accuracy of the recording unit is improved. Moreover, this aspect is not limited to the first aspect above, and may be dependent on any of the second to fourth aspects above.

[0018] A sixth aspect is an aspect dependent on the first aspect, wherein the recording unit includes a protruding portion that protrudes toward the opposing unit, and the recording unit is placed on the opposing unit by using its own weight when the protruding portion abuts against the opposing unit.

[0019] According to this aspect, since the recording unit includes a protruding portion that protrudes toward the opposing unit and the recording unit is placed on the opposing unit by using its own weight when the protruding portion abuts against the opposing unit, contact between the portion of the recording unit that records on the medium and the opposing unit can be avoided. As a result, damage to the portion of the recording unit that records on the medium can be suppressed, and fouling of the opposing unit can also be suppressed. Moreover, this aspect is not limited to the first aspect above, and may be dependent on any of the second to fifth aspects above.

[0020] The seventh aspect is an aspect dependent on the first aspect, wherein the moving region of the recording unit has a first region and a second region farther from the conveyance path than the first region, and the moving means includes a first moving unit that moves the recording unit in the first region and a second moving unit that moves the recording unit in the second region. When the recording unit transitions from the first region to the second region, it shifts from a state of being moved by the first moving unit to a state of being moved by the second moving unit, and when the recording unit transitions from the second region to the first region, it shifts from a state of being moved by the second moving unit to a state of being moved by the first moving unit. The first moving unit and the second moving unit are both driven by the motor.

[0021] According to this aspect, the moving means for moving the recording unit includes a first moving unit that moves the recording unit in the first region and a second moving unit that moves the recording unit in the second region. Since the first moving unit and the second moving unit are driven by a common motor, an increase in the cost of the apparatus can be suppressed, and the apparatus can be made smaller. Further, by configuring the moving means to include the first moving unit and the second moving unit, the amount of movement of the recording unit with respect to one rotation of the output shaft of the motor can be made different between the first moving unit and the second moving unit. As a result, when the moving region includes a region where it is desired to move the recording unit with high accuracy and a region where it is desired to secure the amount of movement of the recording unit, such requirements can be appropriately met. Note that this aspect is not limited to the first aspect above, and may be dependent on any one of the second to sixth aspects.

[0022] The eighth aspect is an aspect dependent on the seventh aspect, wherein the first moving unit is a cam that rotates by the power of the motor, and includes a cam that moves the recording unit by rotating while supporting the recording unit, and the second moving unit includes a rack provided on the recording unit and a pinion that meshes with the rack, and the pinion rotates by the power of the motor to move the recording unit.

[0023] According to this aspect, the first moving part is a cam that rotates by the power of the motor, and includes a cam that rotates while supporting the recording part to move the recording part. Therefore, the position of the recording part can be finely adjusted at a position close to the medium conveyance path. As a result, the recording part can be positioned at an appropriate position according to the thickness of the medium. The second moving part includes a rack provided on the recording part and a pinion that meshes with the rack, and the pinion rotates by the power of the motor to move the recording part. Thereby, even when a large second area is secured, the recording part can be moved accordingly, which is convenient for maintenance work and the like.

[0024] Hereinafter, the present invention will be specifically described. Hereinafter, an inkjet printer 1 will be described as an example of a recording device that performs recording on a medium. Hereinafter, the inkjet printer 1 will be simply referred to as the printer 1. In addition, in each figure, the X - Y - Z coordinate system shown has the X - axis direction as the device width direction, which is the width direction of the medium on which recording is performed. Looking from the operator of the printer 1, the +X direction is the left side, and the -X direction is the right side. Hereinafter, the X - axis direction may be referred to as the medium width direction or simply the width direction. The Y - axis direction is the device depth direction, which is the direction along the medium conveyance direction during recording. The +Y direction is the direction from the back surface to the front surface of the device, and the -Y direction is the direction from the front surface to the back surface of the device. In the present embodiment, among the side surfaces constituting the periphery of the printer 1, the side surface in the +Y direction is the front surface of the device, and the side surface in the -Y direction is the back surface of the device. The Z - axis direction is the direction along the vertical direction, which is the device height direction. The +Z direction is the vertically upward direction, and the -Z direction is the vertically downward direction. In addition, hereinafter, the direction in which the medium is sent may be referred to as "downstream", and the opposite direction may be referred to as "upstream".

[0025] <Printer's Medium Conveyance Path> Hereinafter, the media conveyance path of the printer 1 will be described with reference to FIG. 1. As shown in FIG. 1, the printer 1 includes a media storage cassette 2 at the bottom of the apparatus. The symbol P indicates the media stored in the media storage cassette 2. An example of the media is recording paper. The media storage cassette 2 is detachably provided from the front side of the apparatus.

[0026] A pickup roller 3 driven by a motor (not shown) is provided above the media storage cassette 2. The pickup roller 3 can move forward and backward with respect to the media stored in the media storage cassette 2, and rotates in contact with the media stored in the media storage cassette 2 to send the media out of the media storage cassette 2 in the +Y direction. Downstream of the media storage cassette 2, a feed roller 5 driven by a motor (not shown) and a separation roller 6 to which rotational torque is applied by a torque limiter (not shown) are provided. The media sent out from the media storage cassette 2 is separated by being nipped between the feed roller 5 and the separation roller 6, and is sent further downstream.

[0027] Downstream of the feed roller 5 and the separation roller 6, a reversing roller 8 driven by a motor (not shown) is provided. A first nip roller 9 and a second nip roller 10 are provided around the reversing roller 8. The media is nipped between the reversing roller 8 and the first nip roller 9, and further nipped between the reversing roller 8 and the second nip roller 10 and conveyed. The conveyance direction of the media is reversed from the +Y direction to the -Y direction by the reversing roller 8 and is conveyed downstream.

[0028] Downstream of the reversing roller 8, a first conveyance roller pair 15 including a drive roller 16 driven by a motor (not shown) and a driven roller 17 that can rotate in a driven manner is provided. The media is conveyed by the first conveyance roller pair 15 to a position facing the line head 40. Printer 1 also has a media feeding path from the media support unit 12 in addition to the media feeding path from the media cassette 2. The media support unit 12 supports the media in an inclined posture, and the supported media is conveyed to the first pair of conveying rollers 15 by a feeding roller 13 driven by a motor (not shown). Reference numeral 14 denotes a separating roller to which rotational torque is applied by a torque limiter (not shown).

[0029] Upstream of the first pair of conveying rollers 15, a media detection unit 22 is provided. A control unit 100 (see FIG. 4), which will be described later, can determine the position of the leading edge of the media with respect to the line head 40 based on the detection information of the media detection unit 22, and can position the media at the recording start position, for example.

[0030] The line head 40 is an example of a recording unit that performs recording on the media. The line head 40 is also an example of a liquid ejection head that ejects and records ink, which is an example of a liquid, onto the media. The line head 40 is a liquid ejection head in which a plurality of nozzles 44 for ejecting ink are arranged so as to cover the entire area in the media width direction. The line head 40 is configured as a liquid ejection head that is long in the media width direction and can perform recording over the entire media width without moving in the media width direction.

[0031] Reference numeral 42a denotes a head surface that is the surface facing the media. The head surface 42a can also be referred to as a liquid ejection surface or a nozzle surface. The head surface 42a is formed by a plate member 42 (see FIG. 2), which will be described later. The head surface 42a is parallel to the media conveyance direction, that is, the Y-axis direction, at the position facing the line head 40. The head surface 42a is also parallel to the X-Y plane. The two-dot chain line indicated by Ta is the media conveyance path between the line head 40 and the opposing portion 45. The media conveyance path Ta is parallel to the X-Y plane. Printer 1 includes an ink storage unit (not shown), and the ink ejected from the line head 40 is supplied from the ink storage unit to the line head 40 via an ink tube (not shown).

[0032] A facing portion 45 is provided at a position facing the head surface 42a of the line head 40. The facing portion 45 according to the present embodiment includes an upstream support portion 46 (see FIG. 5) and a shutter 47 (see FIG. 5) described later, and supports the medium by the upstream support portion 46 and the shutter 47 to define a gap between the medium and the head surface 42a. Hereinafter, the gap between the facing portion 45 and the head surface 42a may be referred to as a platen gap.

[0033] The line head 40 is provided so as to be movable in the direction of advancing and retreating with respect to the facing portion 45, that is, in the direction of adjusting the platen gap. In the present embodiment, the direction of adjusting the platen gap is parallel to the Z-axis direction. Hereinafter, when the line head 40 or other component parts move in the +Z-axis direction, it may be referred to as "ascending", and when moving in the -Z direction, it may be referred to as "descending". As shown in FIG. 4, the line head 40 moves along the Z-axis direction by obtaining the power of a head movement motor 101 which is an example of a drive source. Here, with reference to FIG. 4, the movement operation of the line head 40 will be outlined. The power of the head movement motor 101 is converted into an operation in the Z-axis direction of the line head 40 by a movement means 110. The movement means 110 will be described later in detail.

[0034] A control unit 100 that controls the head movement motor 101 raises and lowers the line head 40 according to the thickness of the medium based on the type of medium included in the received print data, and adjusts the platen gap. For example, if the position of the line head 40 when recording on plain paper is set as the first recording position, when recording on a special paper thicker than plain paper, the line head 40 is positioned at a second recording position higher than the first recording position. If the medium comes into contact with the line head 40 even when the second recording position is selected, it is positioned at a third recording position higher than the second recording position.

[0035] In FIG. 4, reference numerals Am1, Am2, and Am3 indicate the moving regions of the line head 40 with respect to the head surface 42a. The moving region of the line head 40 has a first region Am1 and a second region Am2 that is farther from the medium conveyance path Ta than the first region Am1. The first region Am1 includes the first recording position, the second recording position, and the third recording position described above. Of course, the first region Am1 may further include other recording positions. In the present embodiment, the moving region of the line head 40 includes a third region Am3 below the first region Am1.

[0036] When the line head 40 moves to a position Hp2 which is the uppermost position of the second region Am2, the distance between the opposing portion 45 and the head surface 42a becomes the widest. Thereby, when a jam occurs, the jammed medium can be removed. Hereinafter, the position Hp2 is referred to as the jam processing position of the line head 40. The position Hp1 is a recording position when recording is performed on the medium. The position Hp1 changes according to the type of the medium as described above. That is, the recording position Hp1 includes the first recording position, the second recording position, and the third recording position described above. The position Hp0 is the lowermost position of the third region Am3. This position is where the cap portion 61 described later covers the head surface 42a, and hereinafter, the position Hp0 is referred to as the cap position of the line head 40.

[0037] Returning to FIG. 1, a second conveyance roller pair 19 including a drive roller 20 driven by a motor (not shown) and a driven roller 21 that can rotate in a driven manner is provided downstream of the line head 40. The medium on which recording has been performed is sent downstream by the second conveyance roller pair 19. A third conveyance roller pair 27 is provided downstream of the second conveyance roller pair 19, and a discharge roller pair 28 is further provided downstream of the third conveyance roller pair 27. The space between the third conveyance roller pair 27 and the discharge roller pair 28 is configured as a face-down discharge path, and the medium on which recording has been performed is discharged to a discharge tray 29 by the discharge roller pair 28 with the most recent recording surface facing down.

[0038] <Configuration of the Line Head> Next, with reference to FIG. 2, the line head 40, which is an example of a liquid ejection head, will be further described. As shown in FIG. 2, the line head 40 includes a plate member 42 on a base 41. The base 41 is a structure in which a flow path for supplying ink supplied from an ink storage portion (not shown) to the head chip 43 is provided inside.

[0039] The plate member 42 is a metal plate and forms a head surface 42a. A plurality of openings 42d are formed in the plate member 42, and the head chip 43 is provided in each opening 42d. A plurality of nozzles 44 (see FIG. 1) are provided in the head chip 43 along the medium width direction. The plate member 42 and the head chip 43 are provided flush with each other.

[0040] The head chips 43 are alternately arranged at upstream positions and downstream positions along the X-axis direction, that is, the medium width direction. In the present embodiment, three head chips 43 at the upstream position are provided along the medium width direction, and four head chips 43 at the downstream position are provided along the medium width direction. As a result, a cap portion 61, which will be described later and covers the head chips 43, is alternately arranged at upstream positions and downstream positions along the medium width direction.

[0041] The line head 40 is provided on the unit frame 31 and constitutes the head unit 30 together with the unit frame 31. The head unit 30 is a structure including the line head 40. Therefore, it can be said that the members constituting the head unit 30 are the members provided on the line head 40. The line head 40 or the head unit 30 is an example of a recording unit that performs recording on a medium. The power of the head movement motor 101 (see FIG. 4) is transmitted to the unit frame 31, and thereby the head unit 30, that is, the line head 40, moves in the Z-axis direction.

[0042] <Configuration of the Cap Unit> Next, the cap unit 60 will be described with reference to FIG. 3. The cap unit 60 includes a cap portion 61 that covers the head tip 43. Since the head tip 43 is provided on the head surface 42a, the cap portion 61 can also be referred to as a member that covers a part of the head surface 42a. Further, since the nozzle 44 is provided on the head tip 43, the cap portion 61 can also be referred to as a member that covers the nozzle 44. A plurality of cap portions 61 constitute the cap unit 60. The cap unit 60 is provided below the opposing portion 45.

[0043] The cap unit 60 includes a plurality of cap portions 61 provided on a base portion 62. The cap portion 61 has a shape that is long in the X-axis direction, and includes a cap main body portion 61b formed of a resin material or the like, and an elastic portion 61a formed of an elastic material such as rubber at a portion that contacts the head surface 42a. The cap main body portion 61b is held by the base portion 62 so as to be displaceable in the Z-axis direction, and the movement limit in the +Z direction is defined by a regulating portion (not shown) formed on the base portion 62. The cap main body portion 61b is pressed in the +Z direction by a cap spring 63 which is an example of a pressing member. In the present embodiment, two cap springs 63 are provided for one cap main body portion 61b.

[0044] A waste liquid tube (not shown) is connected to each cap main body portion 61b. This waste liquid tube is connected to a pump (not shown). When the pump operates with the cap portion 61 covering the head surface 42a, a negative pressure is generated in the cap portion 61, and ink is thereby sucked from the nozzle 44 of the line head 40.

[0045] The cap portions 61 are alternately arranged at an upstream position and a downstream position along the X-axis direction, that is, the medium width direction. In the present embodiment, three cap portions 61 at the upstream position, that is, in the +Y direction, are provided, and four cap portions 61 at the downstream position, that is, in the -Y direction, are provided. The arrangement of such a cap portion 61 corresponds to the arrangement of the head chip 43 in the line head 40. The cap portion 61 is exposed by moving a shutter 47, which will be described later, from a shielding position to an open position.

[0046] <Configuration of the opposing portion> Next, with reference to FIG. 5, the opposing portion 45 will be further described. The opposing portion 45 facing the line head 40 includes an upstream support portion 46 and a shutter 47 positioned downstream of the upstream support portion 46 as shown in FIG. 5. The shutter 47 is movable along the medium conveyance direction and can move between a shielding position shown as state ST1 in FIG. 5 and open positions shown as states ST2 and ST3 in FIG. 5 by the power of a motor (not shown). When the shutter 47 moves to the open position, an opening 45a is formed in the opposing portion 45, and the cap portion 61 is exposed inside the opening 45a. With the shutter 47 in the open position, when the line head 40 descends as shown in state ST3 in FIG. 5, the cap portion 61 can cover the head chip 43. At this time, the cap portion 61 is slightly pushed downward in the -Z direction against the pressing force of the cap spring 63, whereby the cap portion 61 comes into close contact with the head surface 42a. Note that the descent of the line head 40 when bringing the cap portion 61 into close contact with the head surface 42a in this manner may be referred to as a "cap operation".

[0047] When the power of the apparatus is off or in a recording standby state when the power is on, the control unit 100 sets the shutter 47 to the open position and covers the head chip 43 with the cap portion 61. Further, during a flushing operation for preventing clogging of the nozzles 44, the control unit 100 discharges ink toward the cap portion 61 with the shutter 47, which will be described later, in the open position.

[0048] When the control unit 100 receives recording data and performs recording, it raises the line head 40 to separate the head surface 42a from the cap unit 61, and moves the shutter 47, which will be described later, to the shielding position. This suppresses the medium being conveyed from entering the opening 45a of the opposing unit 45 and the posture of the medium from being disturbed. In addition, it suppresses foreign matter such as paper dust from entering the cap unit 61 during the conveyance of the medium and impairing the performance of the cap unit 61.

[0049] Note that in this embodiment, the shutter 47 moves between the shielding position and the open position by a link mechanism 35 (see FIG. 6) that operates by the reverse rotation of the drive roller 20 that constitutes the second conveyance roller pair 19.

[0050] Note that the upstream support portion 46 is provided so as to be movable in the Z-axis direction and is pressed in the +Z direction by a coil spring 54, which is an example of a pressing member. However, the upstream support portion 46 is regulated in its movement in the +Z direction at a predetermined position by contacting a regulating portion (not shown). When performing the cap operation, the line head 40 pushes down the upstream support portion 46 in the -Z direction against the pressing force of the coil spring 54.

[0051] <Configuration of the moving means for moving the line head> Hereinafter, the moving means 110 that converts the power of the head moving motor 101 (see FIG. 4) into the operation of the line head 40 in the Z-axis direction will be described. First, the position of the line head 40 in the Z-axis direction can be grasped by the control unit 100 based on the detection information transmitted from the rotary encoder 103 (see FIG. 4) and the detection information transmitted from the linear encoder 107 (see FIG. 4). Note that hereinafter, the term "encoder" will be abbreviated as "ENC".

[0052] The rotary ENC 103 includes a rotary scale 104 provided on the motor output shaft of the head movement motor 101 as shown in FIG. 9, and a second detection unit 105 that detects the rotation of the rotary scale 104. The rotary ENC 103 detects the translucent scale of the rotary scale 104 and outputs a detection pulse signal including a number of pulses proportional to the rotation amount of the motor output shaft. The linear ENC 107 includes a linear scale 108 provided on a guide frame 33 described later, and a first detection unit 109 that detects the movement of the linear scale 108. The linear ENC 107 detects the translucent scale of the linear scale 108 and outputs a detection pulse signal including a number of pulses proportional to the movement amount of the head unit 30.

[0053] As described above, the head unit 30 including the line head 40 has a unit frame 31 as a base, and the line head 40 is provided on the unit frame 31. Rack members 32 are provided at the +X-direction end and the -X-direction end of the unit frame 31 as shown in FIG. 8. The rack member 32 provided at the +X-direction end of the unit frame 31 is denoted by reference numeral 32A, and the rack member 32 provided at the -X-direction end is denoted by reference numeral 32B. Hereinafter, when there is no need to distinguish between the rack members 32A and 32B, they are collectively referred to as the rack member 32.

[0054] A guide frame 33 is provided in the +Y direction with respect to the unit frame 31 as shown in FIG. 7. First guide portions 33a are formed at the +X-direction end and the -X-direction end of the guide frame 33. The first guide portion 33a is a portion forming a plane parallel to the Y-Z plane. Further, a second guide portion 33b is formed at the -Y-direction end of the first guide portion 33a. The second guide portion 33b is a portion forming a plane parallel to the X-Z plane. Note that the guide frame 33 is supported by base frames 33A and 33B provided at intervals in the X-axis direction as shown in FIG. 6.

[0055] As shown in FIG. 8, the rack member 32 is provided with guided portions 32c and 32d. By the guided portions 32c and 32d, the first guide portion 33a of the guide frame 33 can be sandwiched in the X-axis direction. Further, the rack member 32 is provided with guided portions 32e and 32f. By the guided portions 32e and 32f, the second guide portion 33b of the guide frame 33 can be sandwiched in the Y-axis direction. With such a configuration, the unit frame 31, that is, the head unit 30 is guided in the Z-axis direction by the guide frame 33. Note that the shape of the rack member 32B is a line-symmetric shape with respect to the Y-axis with the intermediate position between the rack member 32A and the rack member 32B in the X-axis direction as the axis of symmetry, based on the shape of the rack member 32A.

[0056] Next, as shown in FIG. 7, a shaft 77 parallel to the X-axis direction is rotatably supported by the guide frame 33. Rotating bodies 74 are provided near the +X direction end portion and the -X direction end portion of the shaft 77. The rotating body 74 provided near the +X direction end portion of the shaft 77 is denoted by reference numeral 74A, and the rotating body 74 provided at the -X direction end portion is denoted by reference numeral 74B. Hereinafter, when there is no need to distinguish between the rotating bodies 74A and 74B, they are collectively referred to as the rotating body 74. Note that the shape of the rotating body 74B is a line-symmetric shape with respect to the Y-axis with the intermediate position between the rotating body 74A and the rotating body 74B in the X-axis direction as the axis of symmetry, based on the shape of the rotating body 74A. The rotating body 74 rotates integrally with the shaft 77. Hereinafter, in some cases, the rotation directions of the shaft 77, the rotating body 74, and the pinion 72, the cam 66, and the pressing portion 75, which will be described later, may be expressed using the reference numerals C1 and C2 shown in the figure.

[0057] Between the rotating body 74A and the rotating body 74B, a first bevel gear 78 is provided as shown in FIG. 9. The first bevel gear 78 rotates integrally with the shaft 77. The first bevel gear 78 constitutes a speed reduction mechanism 76 (see FIG. 9) that transmits power from the head movement motor 101 to the shaft 77. Hereinafter, the speed reduction mechanism 76 will be described with reference to FIG. 9. The speed reduction mechanism 76 includes a first bevel gear 78, a second bevel gear 79, a spur gear 80, a spur gear 81, a spur gear 82, a worm wheel 83, and a cylindrical worm 84.

[0058] The second bevel gear 79 meshes with the first bevel gear 78. The second bevel gear 79 and the spur gear 80 are integrally formed and are rotatably supported by a mounting frame 34 (see FIG. 6). The mounting frame 34 is screw-fixed to the guide frame 33. Further, a head movement motor 101 is screw-fixed to the mounting frame 34.

[0059] The spur gear 80 meshes with the spur gear 81. The spur gear 81 is rotatably provided on the mounting frame 34 (see FIG. 6). The spur gear 81 meshes with the spur gear 82. The spur gear 82 and the worm wheel 83 are integrally formed and are rotatably provided on the mounting frame 34 (see FIG. 6). The cylindrical worm 84 meshes with the worm wheel 83, and the worm wheel 83 and the cylindrical worm 84 constitute a worm gear mechanism. The cylindrical worm 84 is provided on the output shaft (not shown) of the head movement motor 101. Thus, when the head movement motor 101 rotates, the rotation is transmitted to the shaft 77 via the speed reduction mechanism 76, and the shaft 77 rotates. In addition, in this embodiment, the reduction ratio of the speed reduction mechanism 76, specifically, the reduction ratio of the power transmission from the head movement motor 101 to the shaft 77 is 111. The reduction ratio is preferably greater than 1, more preferably greater than 10, and even more preferably greater than 100 as in this embodiment.

[0060] Next, as shown in FIG. 11, the rotating body 74 is provided with a pinion 72 that constitutes a rack and pinion mechanism. The rotating body 74 is also provided with a cam 66. Further, the rotating body 74 is provided with a lever-shaped pressing portion 75. As shown in FIGS. 8, 10, 13 to 18, a rack 71 that constitutes a rack and pinion mechanism is formed on the rack member 32. The rack 71 meshes with a pinion 72. Therefore, when the pinion 72 rotates, the head unit 30, that is, the line head 40 moves in the Z-axis direction. Specifically, when the pinion 72 rotates in the rotation direction C1, the line head 40 descends, and when the rack 71 rotates in the rotation direction C2, the line head 40 ascends. The rack 71 and the pinion 72 constitute a second moving part 70 that moves the line head 40 in the second region Am2. In addition, since the second moving part 70 raises and lowers the line head 40 by a rack and pinion mechanism, the operation of raising and lowering the line head 40 by the second moving part 70 may be referred to as "rack and pinion drive" hereinafter.

[0061] Also, as shown in FIGS. 8, 10, 13 to 18, the rack member 32 is provided with a contact part 32a that can contact a cam 66. The contact part 32a is provided so as to protrude in the +Y direction, and the cam 66 is disposed below the contact part 32a. The head unit 30, that is, the line head 40, is supported by the cam 66 via the contact part 32a in the first region Am1, so that the position in the Z-axis direction is defined. In other words, the head unit 30, that is, the line head 40 can rest on the cam 66 by using its own weight. Note that the head unit 30, that is, the line head 40 may rest on the cam 66 only by its own weight, or may rest on the cam 66 while receiving a pressing force in a direction including a vertically downward component from a spring or the like. When the head unit 30, that is, the line head 40 receives a pressing force in a direction including a vertically downward component from a spring or the like and rests on the cam 66, the lifting of the head unit 30, that is, the line head 40 is suppressed, and the platen gap is stabilized.

[0062] The outer peripheral surface of the cam 66 is formed such that the distance from the axis center of the shaft 77, that is, the radius, changes along the circumferential direction (see FIG. 12). Therefore, when the cam 66 rotates with the contact portion 32a placed on the cam 66, the head unit 30, that is, the line head 40 moves in the Z-axis direction. Specifically, when the cam 66 rotates in the rotation direction C1, the line head 40 descends, and when the cam 66 rotates in the rotation direction C2, the line head 40 ascends. The cam 66 and the contact portion 32a constitute a first moving portion 65 that moves the line head 40 in the first region Am1. In addition, since the first moving portion 65 raises and lowers the line head 40 by the cam 66, hereinafter, the operation of raising and lowering the line head 40 by the first moving portion 65 may be referred to as "cam drive". The first moving portion 65 and the second moving portion 70 described above constitute a moving means 110 (see FIG. 4).

[0063] Further, the rack member 32 is provided with a pressed portion 32b that can come into contact with a pressing-down portion 75 as shown in FIGS. 10, 13 to 18. The pressed portion 32b is provided so as to protrude in the +Y direction, and the pressing-down portion 75 is configured to be able to come into contact with the pressed portion 32b from above. When the rotating body 74 rotates in the rotation direction C1, the pressing-down portion 75 presses the pressed portion 32b from above, and the head unit 30, that is, the line head 40 can be pushed downward in the -Z direction, that is, downward. The pressing-down portion 75 and the pressed portion 32b constitute a third moving portion 73 that lowers the line head 40 in the third region Am3. In addition, when the line head 40 ascends in the third region Am3, the line head 40 ascends under the pressing force of a coil spring 54 (see FIG. 5), which is an example of the pressing member described above. Therefore, the coil spring 54 (see FIG. 5) also constitutes the third moving portion 73. In addition, since the third moving portion 73 raises and lowers the line head 40 by the lever-shaped pressing-down portion 75, hereinafter, the operation of raising and lowering the line head 40 by the third moving portion 73 may be referred to as "lever drive". In the present embodiment, the third moving portion 73 constitutes the moving means 110 (see FIG. 4).

[0064] Figure 12 shows the formation ranges of the cam 66 and the pinion 72. The pinion 72 has a first phase region Ak1 in which a part of the teeth is missing and a second phase region Ak2 in which the teeth are formed. Hereinafter, when simply referring to the "pinion 72", for convenience, it refers to the part of the second phase region Ak2 where the teeth are formed. The cam 66 has a non-support phase region Aj1 that does not support the contact portion 32a and a support phase region Aj2 that can support the contact portion 32a. In the support phase region Aj2, the radius Ra of the outer peripheral surface that supports the contact portion 32a changes along the circumferential direction. Hereinafter, when simply referring to the "cam 66", for convenience, it refers to the part of the support phase region Aj2.

[0065] Hereinafter, the operations of the first moving part 65, the second moving part 70, and the third moving part 73 will be further described. Figure 13 shows a state where the line head 40 is at the first recording position in the first region Am1. In this state, the first moving part 65 functions. That is, the head unit 30 is in a state of resting on the cam 66 using its own weight. In this state, the rack 71 is not engaged with the pinion 72, and the pressing part 75 is separated from the pressed part 32b. In the first region Am1, that is, the region where recording is performed on the medium, it is necessary to accurately determine the position of the line head 40. Therefore, cam driving by the first moving part 65 is adopted. When the shaft 77 is rotated in the rotation direction C2 from the state shown in Figure 13, the cam 66 also rotates in the rotation direction C2. In this embodiment, the outer peripheral surface of the cam 66 is formed such that when the cam 66 rotates by 1°, the radius changes by 0.01 mm. That is, when the cam 66 rotates by 1°, the line head 40 rises or falls by 0.01 mm.

[0066] Figure 14 shows a state where the shaft 77 rotates in the rotation direction C2 from the state shown in Figure 13 and the line head 40 moves to the second recording position in the first region Am1. Figure 15 shows a state where the shaft 77 further rotates in the rotation direction C2 from the state shown in Figure 14 and the line head 40 moves to the third recording position in the first region Am1. In this way, in the first region Am1, the first moving part 65 with a small movement amount of the line head 40 per unit rotation angle of the shaft 77 functions, so that the line head 40 can be accurately positioned at each recording position. In addition, when lowering the line head 40 from the state of FIG. 15 and positioning it at the second recording position or the first recording position, or when positioning it at the cap position Hp0, the shaft 77 is rotated in the rotation direction C1.

[0067] Next, FIGS. 16 and 17 show the state where the shaft 77 further rotates in the rotation direction C2 from the state of FIG. 15, and FIGS. 16 and 17 are views of the same state. The state shown in FIGS. 16 and 17 is a state where the contact part 32a is placed on the part where the radius Ra of the cam 66 is the largest. When the shaft 77 further rotates in the rotation direction C2 from this state, the contact part 32a will come off the cam 66. Also, this state is a state where the rack 71 starts to engage with the pinion 72 as shown in FIG. 17. In this way, when the line head 40 transitions from the first region Am1 to the second region Am2, it transitions from the state of being moved by the first moving part 65 to the state of being moved by the second moving part 70.

[0068] In addition, when transitioning from the cam drive by the first moving part 65 to the rack and pinion drive by the second moving part 70, as shown in FIGS. 16 and 17, the cam 66 contacts the contact part 32a, that is, the line head 40, and a state where the pinion 72 meshes with the rack 71 is temporarily formed. As a result, even if the contact part 32a comes off the cam 66, the line head 40 will not drop accordingly.

[0069] FIG. 18 shows the state where the shaft 77 further rotates in the rotation direction C2 from the states of FIGS. 16 and 17, and the head unit 30 is raised to the position in the most +Z direction by the second moving part 70, that is, the rack and pinion mechanism. This state is a state where the line head 40 is farthest from the opposing part 45, and it becomes the jam processing position Hp2 when paper jams occur. In addition, in this embodiment, the rack and pinion mechanism including the rack 71 and the pinion 72 is configured such that when the pinion 72 rotates by 1°, the line head 40 moves up or down by approximately 0.26 mm. Therefore, the amount of movement of the line head 40 per unit rotation angle of the shaft 77 is extremely larger in the second moving part 70 than in the first moving part 65. In addition, in this embodiment, when the line head 40 is at the jam processing position Hp2, the platen gap is 30 mm to 40 mm.

[0070] In the above process, that is, in the process of raising the line head 40 from the first recording position to the jam processing position, the shaft 77 is rotated in the rotation direction C2, and there is no need to switch the rotation direction. In addition, the lowest position in the movement area of the line head 40 is the cap position Hp0, and the highest position is the jam processing position Hp2. Similarly, in the process of raising the line head 40 from the cap position Hp0 to the jam processing position Hp2, the shaft 77 is rotated in the rotation direction C2, and there is no need to switch the rotation direction.

[0071] In addition, when the line head 40 descends from the jam processing position Hp2, the situation is reversed. That is, when the line head 40 transitions from the second area Am2 to the first area Am1, it shifts from the rack and pinion drive by the second moving part 70 to the cam drive by the first moving part 65. Specifically, when the line head 40 transitions from the second area Am2 to the first area Am1, the pinion 72 separates from the rack 71, and the contact part 32a is placed on the cam 66. Then, in the process of lowering the line head 40 from the jam processing position Hp2 to the first recording position, the shaft 77 is rotated in the rotation direction C1, and there is no need to switch the rotation direction. Similarly, in the process of lowering the line head 40 from the jam processing position Hp2 to the cap position Hp0, the shaft 77 is rotated in the rotation direction C1, and there is no need to switch the rotation direction.

[0072] When shifting from the rack and pinion drive by the second moving part 70 to the cam drive by the first moving part 65, as shown in FIGS. 16 and 17, the cam 66 comes into contact with the contact part 32a, that is, the line head 40, and a state where the pinion 72 meshes with the rack 71 is temporarily formed. As a result, even if the pinion 72 disengages from the rack 71, the line head 40 will not thereby descend.

[0073] Subsequently, when the line head 40 is to be lowered from the first region Am1, that is, when the cap operation is to be performed, an explanation will be given. Incidentally, when the cap operation is performed, if the shutter 47 (see FIG. 5) provided in the opposing part 45 is in the shielding position, the shutter 47 is moved from the shielding position to the open position as described above prior to the cap operation.

[0074] FIG. 19 shows a state where the line head 40 is in the first region Am1, and more specifically, in the first recording position. At a position in the head unit 30 that faces the upstream support part 46, a protruding part 40a that protrudes toward the opposing part 45 is provided. In this state, a gap Gp is formed between the protruding part 40a and the upstream support part 46. Although not shown in the figure, the protruding part 40a is provided at a position outside the medium conveyance region in the X-axis direction. Also, the protruding part 40a is provided on both sides of the medium conveyance region in the X-axis direction. The protruding part 40a is provided on the unit frame 31 as an example.

[0075] When performing the cap operation from this state, the shaft 77 is rotated in the rotation direction C1. As a result, since the radius Ra of the cam 66 at the position where the contact part 32a contacts the outer peripheral surface of the cam 66 becomes smaller, the line head 40 descends. When the line head 40 descends, the protruding part 40a contacts the upstream support part 46 as shown in FIG. 20, and the descent of the line head 40 stops. This state is a state where the head unit 30 is placed on the upstream support part 46, that is, the opposing part 45, by using its own weight. The pressing force of the coil spring 54 that presses the upstream support part 46 upward is set to a magnitude such that the upstream support part 46 does not displace downward when the head unit 30 is placed on the upstream support part 46 by using its own weight.

[0076] Furthermore, the statement that the line head 40 rests on the opposing portion 45 by utilizing its own weight does not limit the form to the line head 40 resting on the opposing portion 45 solely by its own weight. It also includes the form in which, in addition to its own weight, the line head 40 receives a pressing force in a direction including a vertically downward component from a spring or the like and rests on the opposing portion 45. When the head unit 30, that is, the line head 40, receives a pressing force in a direction including a vertically downward component from a spring or the like and rests on the opposing portion 45, the lifting of the head unit 30, that is, the line head 40, is suppressed, and the platen gap is stabilized. Furthermore, when the protruding portion 40a comes into contact with the upstream support portion 46, since the pressing portion 75 is not in contact with the portion to be pressed 32b, there is a period during which the line head 40 maintains a stopped state even if the shaft 77, that is, the rotating body 74, rotates in the rotation direction C1. This period becomes the idling period of the head movement motor 101, which will be described in detail later.

[0077] When the shaft 77 further rotates in the rotation direction C1 from the state shown in FIG. 20, the pressing portion 75 comes into contact with the portion to be pressed 32b and presses the portion to be pressed 32b downward. That is, the lever drive by the third moving portion 73 is started, and thereby the head unit 30, that is, the line head 40, descends. At this time, the head unit 30 presses the upstream support portion 46 downward against the pressing force of the coil spring 54. FIG. 21 shows a state in which the line head 40 is at the cap position Hp0. In the process of the line head 40 moving to the cap position Hp0, the head surface 42a of the line head 40 comes into contact with the cap portion 61, and further the head surface 42a presses the cap portion 61 downward by a predetermined amount against the pressing force of the cap spring 63. Thereby, the cap portion 61 adheres closely to the head surface 42a.

[0078] When raising the head unit 30, that is, the line head 40, from the state shown in FIG. 21, the shaft 77 is rotated in the rotation direction C2. As a result, since the pressing portion 75 is displaced upward, the line head 40 rises by the spring force of the coil spring 54 while the position in the Z-axis direction is regulated by the pressing portion 75, and returns to the state shown in FIG. 20. When the shaft 77 is further rotated in the rotational direction C2 from the state of FIG. 20, the cam drive by the first moving part 65 is switched.

[0079] Here, in FIG. 21, the symbol k1 is the clearance formed between the cam 66 and the contact part 32a. If there is no such clearance k1, the state of supporting the line head 40 by the cam 66 and the state of the pressing part 75 pressing down the pressed part 32b, that is, the line head 40, are formed simultaneously, and there is a possibility that the rotating body 74 may be in a locked state and unable to rotate. However, by providing the clearance k1, the state of supporting the line head 40 by the cam 66 and the state of the pressing part 75 pressing down the line head 40 are not formed simultaneously, and the lock of the rotating body 74 can be avoided.

[0080] Also, in the present embodiment, as described above, the line head 40 includes a rack member 32 in which the pressed part 32b, the contact part 32a, and the rack 71 are integrally formed. Thereby, the relative positional relationship among the pressed part 32b, the contact part 32a, and the rack 71 becomes easy to determine. As a result, a configuration in which the state of supporting the line head 40 by the cam 66 and the state of the pressing part 75 pressing down the line head 40 are not formed simultaneously can be surely realized.

[0081] In addition, even if the cam 66 moves away from the contact part 32a and the clearance k1 is formed, since the line head 40 is supported by the upstream support part 46, the line head 40 does not descend. However, instead of the configuration in which the upstream support part 46 supports the line head 40 in a state where the cam 66 moves away from the contact part 32a and the clearance k1 is formed, the cap part 61 may be configured to support the line head 40.

[0082] As described above, the printer 1 includes a medium conveyance path Ta for conveying a medium, a line head 40 movable with respect to the medium conveyance path Ta in a direction intersecting the recording surface of the medium, and a moving means 110 for moving the line head 40. The moving area of the line head 40 has a first area Am1 and a second area Am2 that is farther from the media conveyance path Ta than the first area Am1. The moving means 110 includes a first moving unit 65 that moves the line head 40 in the first area Am1 and a second moving unit 70 that moves the line head 40 in the second area Am2. When the line head 40 transitions from the first area Am1 to the second area Am2, it shifts from the state of being moved by the first moving unit 65 to the state of being moved by the second moving unit 70. Also, when the line head 40 transitions from the second area Am2 to the first area Am1, it shifts from the state of being moved by the second moving unit 70 to the state of being moved by the first moving unit 65. The first moving unit 65 and the second moving unit 70 are driven by a head moving motor 101 which is a common drive source. Thereby, compared with a configuration where the first moving unit 65 and the second moving unit 70 are driven by separate drive sources, an increase in the cost of the device can be suppressed, and the device can be miniaturized.

[0083] Also, when the line head 40 transitions from the first area Am1 to the third area Am3, it shifts from the state of being moved by the first moving unit 65 to the state of being moved by the third moving unit 73. Also, when the line head 40 transitions from the third area Am3 to the first area Am1, it shifts from the state of being moved by the third moving unit 73 to the state of being moved by the first moving unit 65. That is, in the present embodiment, in addition to the first moving unit 65 and the second moving unit 70, the third moving unit 73 is driven by one head moving motor 101. As a result, an increase in the cost of the device can be suppressed, and the device can be miniaturized.

[0084] Also, in the present embodiment, the first moving unit 65 is a cam that rotates by the power of the head moving motor 101, and includes a cam 66 that moves the line head 40 by rotating while supporting the line head 40. Thereby, the position of the line head 40 can be finely adjusted at a position close to the media conveyance path Ta. As a result, the line head 40 can be positioned at an appropriate position according to the thickness of the media. Also, in the present embodiment, the second moving part 70 includes a rack 71 provided on the line head 40 and a pinion 72 that meshes with the rack 71. The pinion 72 rotates by the power of the head movement motor 101 to move the line head 40. Accordingly, even when a large second region Am2 is secured, the line head 40 can be moved correspondingly, facilitating maintenance work and the like. However, the first moving part 65 is not limited to cam drive, and other configurations such as rack and pinion drive may be adopted. Also, the second moving part 70 is not limited to rack and pinion drive, and other configurations such as cam drive may be adopted.

[0085] Also, in the present embodiment, the cam 66 and the pinion 72 are integrally formed to constitute a rotating body 74. Thereby, power can be easily transmitted from the head movement motor 101 to the first moving part 65 and the second moving part 70. Also, since there is no need to individually transmit power from the head movement motor 101 to the first moving part 65 and the second moving part 70, the number of parts can be reduced. As a result, an increase in the cost of the device can be suppressed, and the device can be miniaturized. However, the cam 66 and the pinion 72 may be configured separately.

[0086] Furthermore, in the present embodiment, a pressing part 75 is provided on the rotating body 74. Thereby, power can be easily transmitted from the head movement motor 101 to the first moving part 65, the second moving part 70, and the third moving part 73. Also, since there is no need to individually transmit power from the head movement motor 101 to the first moving part 65, the second moving part 70, and the third moving part 73, the number of parts can be reduced. As a result, an increase in the cost of the device can be suppressed, and the device can be miniaturized. However, the pressing part 75 may be configured separately from the rotating body 74.

[0087] Also, in the present embodiment, the pinion 72 has a first phase region Ak1 in which a part of the teeth is missing. When the first phase region Ak1 faces the rack 71, the cam 66 supports the line head 40. Thereby, the following operational effects can be obtained. That is, when the first moving part 65 moves the line head 40, if the second moving part 70 tries to move the line head 40, the position adjustment of the line head 40 by the first moving part 65 may be disrupted. According to this aspect, the pinion 72 has a first phase region Ak1 with a part of its teeth missing. When the first phase region Ak1 faces the rack 71, since the cam 66 supports the line head 40, it is possible to suppress the second moving part 70 from causing an adverse effect when the first moving part 65 tries to move the line head 40.

[0088] Also, in this embodiment, when shifting from the movement of the line head 40 by the cam 66 to the movement of the line head 40 by the pinion 72, and when shifting from the movement of the line head 40 by the pinion 72 to the movement of the line head 40 by the cam 66, a state is temporarily formed in which the cam 66 is in contact with the line head 40 and the pinion 72 meshes with the rack 71. As a result, a state in which the line head 40 is not supported by either the cam 66 or the pinion 72 does not occur. Consequently, it is possible to avoid the occurrence of defects in the line head 40 caused by the line head 40 dropping and being impacted. Note that the state in which the cam 66 is in contact with the line head 40 and the pinion 72 meshes with the rack 71 is different from the states of the above-described first recording position, second recording position, and third recording position. Also, when the cam 66 and the pinion 72 are configured separately, there is a possibility that a state in which the cam 66 is in contact with the line head 40 and the pinion 72 meshes with the rack 71 cannot be temporarily formed due to component tolerances, assembly errors, etc. However, in this embodiment, since the cam 66 and the pinion 72 are integrally configured, the occurrence of the above-described defects can be suppressed.

[0089] Also, in this embodiment, the line head 40 includes a rack member 32 in which a contact portion 32a that contacts the cam 66 and the rack 71 are integrally formed. Thereby, the positional relationship between the contact portion 32a and the rack 71 is easily determined. Here, if the contact portion 32a and the rack 71 are separately configured, there is a possibility that the cam 66 cannot temporarily come into contact with the line head 40 and the pinion 72 cannot mesh with the rack 71 due to component tolerances, assembly errors, etc. However, since the contact portion 32a and the rack 71 are integrally configured and the positional relationship between the contact portion 32a and the rack 71 is easily determined, the occurrence of the above-mentioned problems can be suppressed.

[0090] Also, in the present embodiment, the printer 1 includes a guide frame 33 that guides the line head 40 in the X-axis direction, that is, the moving direction of the line head 40, and a shaft 77 that is the rotation axis of the rotating body 74, and the shaft 77 is rotatably supported by the guide frame 33. As a result, the positional relationship between the rotating body 74 and the rack member 32 is easily determined, the positional relationship between the rack 71 and the pinion 72 is appropriately determined, and the positional relationship between the contact portion 32a and the cam 66 is also appropriately determined. Therefore, the line head 40 can be appropriately moved by the first moving portion 65 and the second moving portion 70.

[0091] Also, in the present embodiment, the head unit 30 includes a plurality of nozzles 44 that discharge ink, which is an example of a liquid, along the medium width direction, and includes a line head 40 that is a liquid discharge head that discharges ink from the nozzles 44 without moving in the medium width direction. A cap portion 61 that covers the head surface 42a, which is the liquid discharge surface of the line head 40, is provided at a position facing the line head 40. The cap portion 61 is displaceable in a direction of advancing and retreating with respect to the line head 40, and the cap portion 61 is pressed toward the line head 40 by a cap spring 63, which is an example of a pressing member. The line head 40 is further movable from the first region Am1 toward a cap position Hp0 where the head surface 42a is covered by the cap portion 61. The rotating body 74 is provided with a pressing portion 75 that presses the line head 40 downward toward the cap portion 61 as the rotating body 74 rotates after the contact between the contact portion 32a of the line head 40 and the cam 66 is released. As a result, the following operational effects are obtained.

[0092] In order to ensure that the head surface 42a of the line head 40 is reliably covered by the cap portion 61, it is necessary to press the head surface 42a against the cap portion 61 against the pressing force of the cap spring 63. The first moving portion 65 moves the line head 40 in the first region Am1, and also moves the line head 40 by the rotation of the cam 66, and cannot press the head surface 42a against the cap portion 61. However, the rotating body 74 is provided with a pressing portion 75 that presses the line head 40 downward toward the cap portion 61 as the rotating body 74 rotates after the contact between the contact portion 32a that contacts the cam 66 in the line head 40 and the cam 66 is released. Thereby, the head surface 42a can be reliably pressed against the cap portion 61, and the head surface 42a can be reliably covered by the cap portion 61. Further, since the pressing portion 75 is provided on the rotating body 74, a separate power source for reliably pressing the head surface 42a against the cap portion 61 becomes unnecessary. As a result, an increase in the cost of the apparatus can be suppressed, and the apparatus can be downsized.

[0093] <Position detection of line head> Next, the position detection in the moving direction of the line head 40 will be described. Hereinafter, when simply referred to as the moving direction, it means the moving direction (Z-axis direction) of the line head 40. First, the control unit 100 will be further described with reference to FIG. 4. The control unit 100 controls the entire printer 1, but the configuration not related to the movement of the line head 40 in FIG. 4 is not shown. The control unit 100 performs various controls including the recording control of the printer 1. The control unit 100 includes one or more processors that operate according to a computer program, in other words, software. The processor includes a CPU and memories such as RAM and ROM, and the memories store program codes or instructions configured to cause the CPU to execute processes. The control unit 100 is not limited to performing software processing. For example, the control unit 100 may include a dedicated hardware circuit, such as an application specific integrated circuit (ASIC), that performs hardware processing for at least a part of the processes it executes.

[0094] The head movement motor 101 is electrically connected to the control unit 100 as an output system. In this embodiment, the head movement motor 101 is a DC motor and is PWM (Pulse Width Modulation) controlled by the control unit 100. Also, an operation unit 115, a rotary ENC 103, and a linear ENC 107 are electrically connected to the control unit 100 as an input system. The operation unit 115 is a part that receives the power on / off, various settings, and recording execution of the printer 1, and can be configured by, for example, a touch panel where a user interface is realized under the control of the control unit 100.

[0095] The control unit 100 includes an arithmetic unit 120, a motor control unit 121, a motor driver 122, a volatile memory 123, and a non-volatile memory 124 which is an example of a storage means. The arithmetic unit 120 performs various arithmetic operations necessary for operating the printer 1. For example, the arithmetic unit 120 performs arithmetic operations such as various setting values necessary for executing the program 125 stored in the non-volatile memory 124. The volatile memory 123 is used as a temporary data storage area.

[0096] The motor control unit 121 controls the head movement motor 101 via the motor driver 122 by outputting a current command value, for example, a duty signal necessary for PWM (Pulse Width Modulation) control, to the motor driver 122. The motor driver 122 includes a D / A converter and controls the current supplied to the head movement motor 101 by performing PWM control based on the duty signal. In this embodiment, the motor control unit 121 performs PID control on the head movement motor 101. The motor control unit 121 multiplies the position deviation between the target rotation position of the head movement motor 101 and the actual rotation position obtained from the output signal of the rotary ENC 103 by the gain Kp to calculate the target rotation speed. Then, based on the speed deviation between this target rotation speed and the actual rotation speed obtained from the output of the rotary ENC 103, the motor control unit 121 performs operations on the proportional component, integral component, and differential component using the proportional element, integral element, and differential element, and based on the sum of these operation results, sends a duty signal to the motor driver 122. Note that the motor control unit 121 may control the head movement motor 101 based on the output signal of the linear ENC instead of the output signal of the rotary ENC 103.

[0097] The calculation unit 120 detects the edge of the output pulse of the rotary ENC 103, counts the number thereof, and calculates the rotation position of the head movement motor 101 based on this count value. The calculation unit 120 distinguishes between the forward rotation and reverse rotation of the head movement motor 101 from the comparison process of the two pulse signals output from the rotary ENC 103. Then, when one edge is detected, the calculation unit 120 performs a counting process so as to increment and decrement the rotation position of the head movement motor 101 according to the forward rotation and reverse rotation. The "Rotary ENC Position" shown in FIGS. 22 and 23 has the vertical axis as the rotation position of the head movement motor 101 obtained by the above counting process, the upward direction being the increment direction, that is, the upward direction of the line head 40, and the downward direction being the decrement direction, that is, the downward direction of the line head 40.

[0098] Still, the rotary ENC 103 outputs two pulse signals, pulse ENC-A and pulse ENC-B. In both the forward rotation and reverse rotation of the head movement motor 101, the phases of pulse ENC-A and pulse ENC-B are shifted by 90 degrees. When the head movement motor 101 is rotating forward, the phase of pulse ENC-A leads that of pulse ENC-B by 90 degrees. On the other hand, when the head movement motor 101 is rotating in reverse, the phase of pulse ENC-A lags that of pulse ENC-B by 90 degrees. The time for one cycle of each pulse is equal to the time it takes for the head movement motor 101 to rotate by the interval of the slits of the rotary scale 104. Thereby, the arithmetic unit 120 can detect the rotation speed of the head movement motor 101. The "rotary ENC speed" shown in FIGS. 22 and 23 corresponds to the rotation speed.

[0099] Still, the arithmetic unit 120 can calculate the movement amount of the line head 40 based on the rotation amount of the head movement motor 101 and the reduction ratio of the reduction mechanism 76 described above. Also, if the arithmetic unit 120 detects the time for one cycle of each pulse, it can calculate the movement speed of the line head 40 based on the reduction ratio of the reduction mechanism 76 described above. However, when the signal change of the linear ENC 107 is not detected, that is, when the position of the linear ENC described later does not change, even if the position of the rotary ENC 103 changes, the line head 40 does not move.

[0100] Also, the arithmetic unit 120 can detect the edge of the output pulse of the linear ENC 107, count the number thereof, and calculate the position in the movement direction of the line head 40 based on this count value. The arithmetic unit 120 distinguishes between the upward and downward movement of the line head 40 from the comparison process of the two pulse signals output from the linear ENC 107. Then, when one edge is detected, the arithmetic unit 120 performs a counting process so as to execute an increment and a decrement of the position of the line head 40 according to the upward and downward movement. The "Linear ENC Position" shown in FIGS. 22 and 23 has the vertical axis representing the position obtained by the above counting process and corresponding to the position in the moving direction of the line head 40. The linear ENC position has the upward direction as the increment direction, i.e., the upward movement direction of the line head 40, and the downward direction as the decrement direction, i.e., the downward movement direction of the line head 40.

[0101] Note that the linear ENC 107 outputs two pulse signals, pulse ENC-A and pulse ENC-B. In both the case of the line head 40 rising and falling, the phases of pulse ENC-A and pulse ENC-B are shifted by 90 degrees. When the line head 40 is rising, the phase of pulse ENC-A leads that of pulse ENC-B by 90 degrees. On the other hand, when the line head 40 is falling, the phase of pulse ENC-A lags that of pulse ENC-B by 90 degrees. The time for one cycle of each pulse is equal to the time for the line head 40 to move by the interval of the slit of the linear scale 108. If the arithmetic unit 120 counts the number of pulse signals, the movement amount of the line head 40 can be detected. Also, if the arithmetic unit 120 detects the time for one cycle of each pulse, the movement speed of the line head 40 can be calculated. The "Linear ENC Speed" shown in FIGS. 22 and 23 corresponds to the above movement speed.

[0102] Hereinafter, the outline of the origin detection method for the line head 40 will be described. As an example, when the line head 40 descends from the recording position Hp1 shown in FIG. 19, both the rotary ENC 103 and the linear ENC 107 generate signal changes until the protruding portion 40a provided on the line head 40 contacts the upstream support portion 46. This is shown in the rotary ENC position and the linear ENC position during the cam drive period shown in FIG. 22. When the protrusion 40a provided on the line head 40 abuts against the upstream support portion 46, the downward movement of the line head 40 temporarily stops, so the signal change of the linear ENC107 disappears. This is shown in the linear ENC position during the motor idling period shown in FIG. 22. However, since the head movement motor 101 continues to rotate, as shown in the rotary ENC position during the motor idling period shown in FIG. 22, the signal change of the rotary ENC103 continues to occur.

[0103] The control unit 100 can utilize this property to set the origin position of the line head 40. That is, when the control unit 100 lowers the line head 40 toward the opposing portion 45, based on the position of the line head 40 when the signal change of the linear ENC107 disappears while the signal change of the rotary ENC103 is present, the control unit 100 sets the origin position of the line head 40. In FIG. 22, the position Pm0 is the rotary ENC position when the signal change of the linear ENC107 disappears, that is, the origin position of the rotary ENC103, and the position Pn0 is the linear ENC position when the signal change of the linear ENC107 disappears, that is, the origin position of the linear ENC107.

[0104] The position in the moving direction of the line head 40 may be grasped based on the origin position of the rotary ENC103 or based on the origin position of the linear ENC107. In either case, the distance from the origin position to the boundary of each region can be stored in the non-volatile memory 124 as a known value. As a result, the control unit 100 can grasp the current position of the line head 40. In this embodiment, the encoder resolution with respect to the single displacement amount of the line head 40 by the speed reduction mechanism 76 is higher for the rotary ENC103 than for the linear ENC107. Therefore, for ensuring the stop position accuracy of the line head 40, it is preferable to perform the basic speed control of the head movement motor 101 based on the output signal of the rotary ENC103.

[0105] Even when raising the line head 40, the origin position of the line head 40 can be set. For example, when the line head 40 rises from the cap position Hp0, both the rotary ENC 103 and the linear ENC 107 generate signal changes until the upstream support portion 46 rises to the upper limit position. This is shown in the rotary ENC position and the linear ENC position during the lever drive period shown in FIG. 23. When the upstream support portion 46 rises to the upper limit position and the pressing portion 75 moves upward away from the pressed portion 32b, the rise of the line head 40 temporarily stops, so the signal change of the linear ENC 107 disappears. This is shown in the linear ENC position during the motor idling period shown in FIG. 23. However, since the head movement motor 101 continues to rotate, as shown in the rotary ENC position during the motor idling period shown in FIG. 23, the signal change of the rotary ENC 103 continues to occur. Then, when the cam 66 contacts the contact portion 32a and lifts the line head 40, the protruding portion 40a separates from the upstream support portion 46, and the line head 40 rises. This is shown in the linear ENC position when transitioning from the motor idling period to the cam drive period shown in FIG. 23.

[0106] The control unit 100 can utilize this property to set the origin position of the line head 40. That is, the control unit 100 sets the origin position of the line head 40 based on the position of the line head 40 when a signal change of the linear ENC 107 occurs while the signal change of the rotary ENC 103 is present. In FIG. 23, the position Pm0 is the rotary ENC position when the signal change of the linear ENC 107 disappears, that is, the origin position of the rotary ENC 103, and the position Pn0 is the linear ENC position when the signal change of the linear ENC 107 disappears, that is, the origin position of the linear ENC 107.

[0107] Hereinafter, the processing executed by the control unit 100 will be further described with reference to FIG. 24. The control unit 100 sets the origin position of the line head 40 described above at a predetermined timing (step S101). This origin position setting can be performed when the printer 1 is powered on, or when the elapsed time since the previous origin position setting has exceeded a predetermined time. Next, the control unit 100 sets the rotary ENC position as shown in step S102. Note that the position in step S102 may be the rotary ENC position or the linear ENC position.

[0108] As a result, the rotary ENC position in the lever drive region is set to "position < origin - dx1". The distance dx1 is the distance from the origin position to the lever drive region. Also, the rotary ENC position in the cam drive region is set to "origin ≤ position < origin + dx2". The distance dx2 is the distance from the origin position to the rack and pinion drive region. Also, the rotary ENC position in the rack and pinion drive region is set to "origin + dx2 ≤ position". The values dx1 and dx2 are stored in the non-volatile memory 124 as part of the control parameter 126 (see FIG. 4). Note that the lengths of the lever drive region and the rack and pinion drive region are also stored in the non-volatile memory 124 as part of the control parameter 126 (see FIG. 4).

[0109] Next, when the control unit 100 moves the line head 40 (Yes in step S103), it determines whether the printing mode is the normal mode (step S104). The printing mode can be selected by the user via the operation unit 115 as either the normal mode or the speed priority mode. In the case of the normal mode, the control unit 100 temporarily stops the line head 40 before the region boundary and selects control parameters for each region (step S105). Also, in the case of the speed priority mode, the control unit 100 continuously drives without stopping the line head 40 at the region boundary and selects control parameters for each region (step S106).

[0110] The control parameters for each area are stored in the non-volatile memory 124 as part of the control parameter 126 (see FIG. 4). The control parameters for each area include the torque limit value of the head movement motor 101. The torque limit value is, for example, the limit value of the duty signal sent to the motor driver 122, whereby the drive current value of the head movement motor 101 is limited. The torque limit value for each area is stored in the non-volatile memory 124 as part of the control parameter 126 (see FIG. 4). By setting the torque limit value, it is possible to prevent an excessive load from being applied to the drive mechanism in the event of an abnormality.

[0111] FIG. 27 shows the head movement speed, motor rotation speed, motor drive load, and torque limit value for each area when the line head 40 rises and when it falls. When the line head 40 is falling, the head movement speed is the lowest in the first area Am1, i.e., in the case of cam drive, the highest in the second area Am2, i.e., in the case of rack and pinion drive, and intermediate in the third area Am3, i.e., in the case of lever drive. Also, when the line head 40 is falling, the motor rotation speed is speed 2 in each area. However, for example, in order to mitigate the impact when the line head 40 abuts an obstacle in the second area Am2 or the third area Am3, it may be set to a speed lower than speed 2.

[0112] Also, when the line head 40 descends, the driving load of the head movement motor 101 is the smallest in the first region Am1 and the second region Am2, and becomes larger in the third region Am3 than in the first region Am1 and the second region Am. Therefore, when the line head 40 descends, the torque limit values are the smallest in the first region Am1 and the second region Am2, and become larger in the third region Am3 than in the first region Am1 and the second region Am. In the third region Am3, this is because the pressing portion 75 presses down the line head 40 against the spring forces of the coil spring 54 (see FIG. 20) and the cap spring 63 (see FIG. 20). This is shown in the motor duty in the lever drive region shown in FIG. 22. When the line head 40 descends, in the third region Am3, the head movement motor 101 first receives a load from the coil spring 54, and then receives loads from both the coil spring 54 and the cap spring 63. Therefore, as the line head 40 descends, the motor duty increases. Therefore, the torque limit value is the largest in the third region Am3.

[0113] Next, when the line head 40 ascends, the head movement speed is the lowest in the first region Am1, i.e., in the case of cam drive, the highest in the second region Am2, i.e., in the case of rack and pinion drive, and intermediate in the third region Am3, i.e., in the case of lever drive. Also, when the line head 40 ascends, the motor rotation speed becomes speed 1 in each region. However, for example, in order to mitigate the impact when the line head 40 abuts against an obstacle in the second region Am2 or the third region Am3, it may be set to a speed lower than speed 1. Note that speed 1 may be equal to speed 2, higher than speed 2, or lower than speed 2.

[0114] When the line head 40 rises, the driving load of the head movement motor 101 is the smallest in the third region Am3 and the first region Am1, and becomes larger in the second region Am2 than in the first region Am1 and the second region Am. However, when the line head 40 rises, the torque limit value is the largest in the third region Am3. This is because when meshing occurs in the worm gear mechanism during head descent, when the head rises, there is a possibility that a motor driving load larger than the motor driving load during head descent will be applied. Incidentally, the torque limit value is the smallest in the first region Am1, and becomes larger in the second region Am2 than in the first region Am1.

[0115] Next, with reference to FIG. 25, a process of raising the line head 40 from the state where the line head 40 is placed on the upstream support portion 46 via the protruding portion 40a and performing origin detection of the line head 40 will be described. The control unit 100 starts driving the head movement motor 101 to raise the line head 40 in a state where the line head 40 is placed on the upstream support portion 46 via the protruding portion 40a (step S201). Next, when a signal change of the linear ENC107 occurs (Yes in step S202), assuming that the number of edges of the output pulse of the linear ENC107 is Ce1, the origin position based on the linear ENC107 is set before the Ce1 edge (step S203). An example of the number of edges Ce1 is 1.

[0116] Next, the control unit 100 sets the origin position based on the rotary ENC103 before the Ce1×(Rs1 / Rs2) edge (step S204). Here, Rs1 is the resolution of the rotary ENC103, specifically, the number of edges of the output pulse of the rotary ENC103 with respect to the unit displacement amount of the line head 40. Also, Rs2 is the resolution of the linear ENC107, specifically, the number of edges of the output pulse of the linear ENC107 with respect to the unit displacement amount of the line head 40. By setting the origin position of the line head 40 in this way, the origin position of the line head 40 can be accurately set.

[0117] Next, with reference to FIG. 26, a process of performing origin detection of the line head 40 by lowering the line head 40 from a state where the protruding portion 40a of the line head 40 is separated from the upstream support portion 46 will be described. The control unit 100 starts driving the head movement motor 101 to lower the line head 40 (step S301). Next, when the signal change of the linear ENC 107 disappears (Yes in step S302), if there is a signal change in the rotary ENC 103 (Yes in step S303), the origin position based on the linear ENC 107 is set to the linear ENC position at the time when the signal change of the linear ENC 107 disappears (step S304). Further, the control unit 100 sets the origin position based on the rotary ENC 103 to the rotary ENC position at the time when the signal change of the linear ENC 107 disappears (step S305). By setting the origin position of the line head 40 in this way, the origin position of the line head 40 can be accurately set. For the origin position setting in step S101 of FIG. 24, the process shown in FIG. 25 may be adopted, or the process shown in FIG. 26 may be adopted.

[0118] Still, when the signal change of the linear ENC 107 disappears (Yes in step S302), if the signal change of the rotary ENC 103 also disappears within the movement area of the line head 40 (No in step S303), it is determined that the head unit 30 has come into contact with some obstacle, the head movement motor 101 is stopped (step S306), and error processing is performed. As an example of the error processing, an alert indicating that an abnormality has occurred is displayed on the operation unit 115. Thereby, an excessive load can be prevented from being applied to the line head 40 and the moving means 110, and damage to the line head 40 and the moving means 110 can be suppressed.

[0119] Still, there is play such as gear backlash in the moving means 110. Therefore, particularly when the line head 40 is raised after setting the origin position of the line head 40 while lowering the line head 40, and when the line head 40 is raised based on the origin position of the rotary ENC 103, it is preferable to set the target stop position of the head movement motor 101 in consideration of the above backlash.

[0120] Next, the processing when the power of the printer 1 is not turned off in the normal procedure will be described with reference to FIG. 28. When the power of the printer 1 is turned off in the normal procedure, specifically, when the user presses a power button (not shown) to turn off the power, the line head 40 is moved to the cap position. Therefore, in this case, when the power of the printer 1 is turned on, the control unit 100 can determine that the line head 40 is in the cap position. However, when the power of the printer 1 is not turned off in the normal procedure, for example, when the power cord is unplugged while the power is on, and then the power of the printer 1 is turned on, the control unit 100 cannot grasp the exact current position of the line head 40. Therefore, in this case, an exception process for grasping the current position of the line head 40 is required. Still, it is also possible to grasp the position of the line head 40 by abutting the line head 40 against one end or the other end of the moving area and detecting an increase in the drive current value of the head movement motor 101 at that time. However, in this method, excessive surface pressure may occur between the worm wheel 83 (see FIG. 9) and the cylindrical worm 84 (see FIG. 9) constituting the worm gear mechanism, leading to locking, which is not preferable.

[0121] Whether or not the power of the printer 1 has been turned off in the normal procedure can be determined by storing a power flag indicating that in the non-volatile memory 124 (see FIG. 4) when the power of the printer 1 is turned off in the normal procedure. For example, when the power of the printer 1 is turned off in the normal procedure, the control unit 100 stores "1" in the non-volatile memory 124 as the above power flag. Then, when the power of the printer 1 is turned on, the control unit 100 reads the above power flag, and if it is "1", it performs the origin position setting in the normal procedure (step S101 in FIG. 24). And at that time, the above power flag is reset to "0". Also, when the power of the printer 1 is turned on, the control unit 100 reads the above power flag, and if it is "0", it performs the exception processing shown in FIG. 28 on the assumption that the power of the printer 1 has not been turned off in the normal procedure.

[0122] In FIG. 28, when the power of the printer 1 is turned on, the control unit 100 determines whether it is a power-on from a normal power-off (step S401). If it is a power-on from a normal power-off (Yes in step S401), it performs the normal origin position setting (step S405). Note that the process of step S405 is the same as the process of step S101 in FIG. 24. When the power-on is not from a normal power-off (No in step S401), the control unit 100 drives the head movement motor 101 by a predetermined amount in the direction opposite to the previous driving direction (step S402).

[0123] Here, the previous driving direction is the driving direction when the control unit 100 last drove the head movement motor 101. Each time the control unit 100 drives the head movement motor 101, it stores a direction flag indicating the rotation direction in the non-volatile memory 124 (see FIG. 4). By reading the above direction flag, the control unit 100 can grasp the rotation direction when the head movement motor 101 was last driven. Also, the "predetermined amount" in step S402 is preferably as small as possible within the range where the linear ENC speed can be detected. For example, the above "predetermined amount" is preferably 5.0 mm or less, more preferably 3.0 mm or less, when converted to the moving amount of the line head 40. The above "predetermined amount" is stored in the non-volatile memory 124 as part of the control parameter 126 (see FIG. 4). By minimizing the above "predetermined amount" in this way, when the line head 40 is moved, it is possible to suppress the line head 40 from coming into contact with any obstacle and causing the lock of the worm gear mechanism described above.

[0124] Next, the control unit 100 determines in which area the line head 40 is currently located based on the linear ENC speed (step S403). As described with reference to FIG. 27, the moving speed of the line head 40, that is, the linear ENC speed, is different in each of the first area Am1, the second area Am2, and the third area Am3. That is, the linear ENC speed when the head moving motor 101 is rotated at a predetermined rotational speed is different in each area and can be obtained as a known value. Therefore, the control unit 100 can determine in which area of each area the line head 40 is based on the linear ENC speed. Of course, if the linear ENC speed when the head moving motor 101 is rotated at a predetermined rotational speed is zero, it can be determined that the line head 40 is in the motor idling area of FIGS. 22 and 23. The moving speeds of the line head 40 in each area when the head moving motor 101 is rotated at a predetermined rotational speed are stored in the non-volatile memory 124 as part of the control parameter 126 (see FIG. 4). Of course, the above moving speed is a value with a width considering errors.

[0125] If it is possible to determine in which area the line head 40 is located, it is possible to determine in which direction the line head 40 should be moved to set the origin position. Therefore, the control unit 100 sets the origin position based on in which area the line head 40 is located (step S404). For example, if the line head 40 is in the second area Am2 or the first area Am1, the origin position can be set by lowering the line head 40. Also, if the line head 40 is in the third area Am3 or the motor idling area, the origin position can be set by raising the line head 40. The origin position setting by raising the line head 40 is the process shown in FIG. 25, and the origin position setting by lowering the line head 40 is the process shown in FIG. 26.

[0126] In addition, when the linear ENC speed is zero when the head movement motor 101 is rotated at a predetermined rotational speed, it is conceivable that the line head 40 is in the motor idling area and that the line head 40 is in contact with some part and cannot move. However, in step S402, the head movement motor 101 is driven in the direction opposite to the previous driving direction. Therefore, it is possible to avoid a state in which the line head 40 cannot move because it has hit at least one end of the moving area. As described above, even when the power of the printer 1 is not turned off in the normal procedure, the current position of the line head 40 can be grasped based on the detection information of the rotary ENC 103 and the linear ENC 107. Also, at that time, the occurrence of the lock of the worm gear mechanism described above can be suppressed.

[0127] In addition, in the above embodiment, the control unit 100 determines in which area the line head 40 is currently located based on the linear ENC speed. However, instead of the linear ENC speed, the motor drive load, specifically the motor drive current value, may be adopted. This is because the motor drive load, that is, the motor drive current value, is different in each area.

[0128] If the shutter 47 (see FIG. 5) is closed, the line head 40 is in the first area Am1 or the second area Am2. Therefore, when a sensor for detecting the position of the shutter 47 is provided, the position of the line head 40 may be grasped with reference to the position of the shutter 47. Also, when a sensor for detecting that the cap unit 60 is in the lowered position is provided, the position of the line head 40 may be grasped with reference to the state of this sensor. For example, if the cap unit 60 is not in the lowered position, the line head 40 is lowered. Thereby, when the lowered position of the cap unit 60 is detected, it can be determined that the line head 40 is in the cap position.

[0129] Hereinafter, the operation and effect of the printer 1 configured as described above will be described. First, as described above, the moving direction of the line head 40 includes a vertical direction component. The position detection means for detecting the position of the line head 40 with respect to the medium conveyance path Ta is a linear ENC 107 including a linear scale 108 provided along the moving direction of the line head 40 and a first detection unit 109 provided on the line head 40 for detecting the linear scale 108. The moving means 110 that moves the line head 40 under the power of the head moving motor 101 has a configuration that allows the head moving motor 101 to idle after the line head 40 has landed on the opposing portion 45 by using its own weight when the line head 40 is lowered toward the opposing portion 45. This idling of the head moving motor 101 corresponds to the rotation of the head moving motor 101 in the motor idling region shown in FIGS. 22 and 23. That is, the idling of the head moving motor 101 means a state in which the rotation of the head moving motor 101 is not converted into the movement of the line head 40 and the head moving motor 101 does not receive a load from the line head 40.

[0130] Then, when the line head 40 descends onto the opposing part 45, the control unit 100 grasps the position of the line head 40 in the moving direction based on the change in the detection signal of the linear ENC 107 (linear ENC position Pn0 in FIG. 22), or when the line head 40 ascends from the state of being placed on the opposing part 45, based on the change in the detection signal of the linear ENC 107 (linear ENC position Pn0 in FIG. 23). Thereby, the position of the line head 40 relative to the opposing part 45 can be appropriately grasped, and thus the platen gap can be appropriately set. Also, the line head 40 can be appropriately positioned at the cap position Hp0 or the jam processing position Hp2.

[0131] In addition, since the platen gap can be set with high precision, adjustment in the device assembly process becomes unnecessary, and the assembly time can be shortened. Also, even if the components such as gears constituting the moving means 110 are deformed from the assembled state due to the impact during the transportation of the device, it is easy to obtain the desired platen gap. Also, even if the members such as gears constituting the moving means 110 wear due to aging deterioration, it is difficult for this to affect the platen gap.

[0132] In addition, when the moving means 110 lowers the line head 40 toward the opposing part 45, since the moving means 110 has a configuration that allows the head movement motor 101 to idle after the line head 40 has landed on the opposing part 45 using its own weight, the following operational effects can be obtained. For example, in a configuration where the position in the moving direction of the line head 40 is grasped by detecting an increase in the drive current value of the head movement motor 101 when the line head 40 abuts against the opposing portion 45, a load is applied to the moving means 110, which may cause damage to the components. Also, it may be difficult to appropriately set the threshold value of the drive current value. Further, if the moving means 110 includes a worm gear mechanism (see FIG. 9) as in this embodiment, there is also a risk that excessive surface pressure will occur between the worm wheel 83 and the cylindrical worm 84 and cause locking. However, when the moving means 110 lowers the line head 40 toward the opposing portion 45, the moving means 110 has a configuration that allows the head movement motor 101 to idle after the line head 40 has rested on the opposing portion 45 by utilizing its own weight. Thereby, the occurrence of the above-mentioned problems can be suppressed.

[0133] Also, in this embodiment, a rotary ENC 103, which is a rotation detection means for detecting the rotation of the head movement motor 101, is provided. And the control unit 100 grasps the position in the moving direction of the line head 40 based on the detection signal of the linear ENC 107 and the detection signal of the rotary ENC 103. Thereby, the position in the moving direction of the line head 40 can be accurately grasped.

[0134] Also, in this embodiment, the rotation detection means is a rotary ENC 103 including a rotary scale 104 provided on the motor output shaft of the head movement motor 101 and a second detection unit 105 for detecting the rotary scale 104. Thereby, the rotation of the head movement motor 101 can be accurately detected.

[0135] Also, the moving means 110 includes a cylindrical worm 84 driven by the head movement motor 101 and a worm wheel 83 that meshes with the cylindrical worm 84 and rotates as the cylindrical worm 84 rotates. In such a configuration, as described above, if excessive surface pressure occurs between the worm wheel 83 and the cylindrical worm 84, there is also a risk of locking. However, as described above, when grasping the position of the line head 40 with respect to the opposing portion 45, an excessive load is not applied to the moving means 110, so the occurrence of the above-mentioned locking can be suppressed. In addition, the worm gear mechanism can increase the reduction ratio when transmitting power from the head movement motor 101 to the line head 40. As a result, the resolution of the rotary ENC 103 can be made larger than the resolution of the linear ENC 107, and the line head 40 can be accurately positioned with respect to the opposing portion 45.

[0136] Further, when the control unit 100 lowers the line head 40 toward the opposing portion 45, the position of the line head 40 at the time when the signal change of the linear ENC 107 disappears during the rotation of the head movement motor 101 (linear ENC position Pn0 in FIG. 22), or when the line head 40 is raised from the state of being placed on the opposing portion 45, the position of the line head 40 at the time when the signal change of the linear ENC 107 occurs during the rotation of the head movement motor 101 (linear ENC position Pn0 in FIG. 23), based on this, the origin position of the line head 40 in the moving direction is set. In other words, when the control unit 100 lowers the line head 40 toward the opposing portion 45, the position of the line head 40 at the time when the signal change of the linear ENC 107 disappears while the signal change of the rotary ENC 103 exists (linear ENC position Pn0 in FIG. 22), or when the line head 40 is raised from the state of being placed on the opposing portion 45, the position of the line head 40 at the time when the signal change of the linear ENC 107 occurs while the signal change of the rotary ENC 103 exists (linear ENC position Pn0 in FIG. 23), based on this, the origin position of the line head 40 in the moving direction is set. In addition, the control method realized by the control unit 100 includes the step of setting the origin position of the line head 40 in the moving direction based on the position of the line head 40 at the time when the signal change of the linear ENC 107 disappears while the signal change of the rotary ENC 103 exists when the line head 40 is lowered toward the opposing portion 45, or the position of the line head 40 at the time when the signal change of the linear ENC 107 occurs while the signal change of the rotary ENC 103 exists when the line head 40 is raised from the state of being placed on the opposing portion 45. As a result, the origin in the moving direction of the line head 40 can be appropriately set by utilizing the signal change of the linear ENC 107. Consequently, the positioning accuracy of the line head 40 is improved.

[0137] The line head 40 also includes a protruding portion 40a that protrudes toward the opposing portion 45. When the protruding portion 40a abuts against the opposing portion 45, the line head 40 rests on the opposing portion 45 by utilizing its own weight. This can avoid contact between the part of the line head 40 that records on the medium, specifically the head chip 43 (see FIG. 2), and the opposing portion 45. As a result, damage to the head chip 43 can be suppressed, and fouling of the opposing portion 45 can also be suppressed.

[0138] In addition, a plurality of protruding portions 40a are provided in the medium width direction, and by bringing the protruding portions 40a into contact with the opposing portion 45, the posture of the line head 40 with respect to the opposing portion 45 is also appropriately determined. Therefore, for example, the position of the line head 40 when the protruding portion 40a abuts against the opposing portion 45 may be set as the first recording position. As a result, the platen gap is set extremely appropriately, and the parallelism of the line head 40 with respect to the opposing portion 45 can also be ensured, and appropriate recording quality can be obtained. In addition, in order to grasp the posture of the line head 40 with respect to the opposing portion 45, a plurality of linear ENCs 107 may be provided at intervals in the X-axis direction, and thereby the posture of the line head 40 with respect to the opposing portion 45 may be detected. Also, in that case, in order to correct the posture of the line head 40 with respect to the opposing portion 45, the rotating body 74A provided near the +X direction end of the shaft 77 and the rotating body 74B provided at the -X direction end may be driven by separate motors.

[0139] In this embodiment, the moving means 110 has a speed reduction mechanism 76 with a speed reduction ratio greater than 1 when transmitting power from the head moving motor 101 to the recording head. The control unit 100 grasps the position of the line head 40 in the moving direction based on the signal of the linear ENC 107, and controls the head moving motor 101 based on the signal of the rotary ENC 103. In other words, the control method realized by the control unit 100 includes the steps of grasping the position of the line head 40 in the moving direction based on the signal of the linear ENC 107 and controlling the head moving motor 101 based on the signal of the rotary ENC 103.

[0140] According to such a configuration, since the linear ENC 107 directly detects the movement of the line head 40, the position of the line head 40 can be appropriately grasped. As a result, it becomes easier to appropriately adjust the gap between the line head 40 and the opposing portion 45. Also, by referring to the detection signal of the linear ENC 107 during motor control based on the detection signal of the rotary ENC 103, the position of the line head 40 can be accurately grasped without being affected by the backlash of the gears constituting the moving means 110.

[0141] Here, since the linear ENC 107 is configured to directly detect the movement of the line head 40, there is a possibility that the stop accuracy when stopping the head moving motor 101 cannot be obtained due to the resolution of the linear ENC 107. As a result, there is a possibility that the line head 40 cannot be accurately stopped at a desired position. However, in this embodiment, the moving means 110 has a speed reduction mechanism 76 with a speed reduction ratio greater than 1 when transmitting power from the head moving motor 101 to the line head 40. From this, the resolution of the rotary ENC 103 can be ensured. Then, by controlling the head moving motor 101 based on the signal of the rotary ENC 103, the stop accuracy when stopping the head moving motor 101 can be improved, and it becomes easier to accurately stop the line head 40 at a desired position.

[0142] Further, the control unit 100 detects each region constituting the movement region based on the origin position of the line head 40 in the movement direction, and controls the head movement motor 101 with control parameters corresponding to each region. Therefore, by appropriate control according to each region, the line head 40 can be appropriately positioned.

[0143] Also, the control parameters include the torque limit value of the head movement motor 101. Thereby, the following effects can be obtained. When the loads applied to the head movement motor 101 are different in each region constituting the movement region of the line head 40, the required motor drive torques are different. Therefore, if a large torque limit value is set for a region with a small load, there is a risk that an excessive load will be applied to the mechanism parts in the event of an abnormality, leading to damage to the mechanism parts or the like. However, since the above control parameters include the torque limit value of the head movement motor 101, damage to the mechanism parts described above can be suppressed. Note that the above control parameters may be other parameters such as the target speed of the head movement motor 101, the gain Kp of PID control, or any two or more of these multiple parameters.

[0144] Further, at the boundary of each region constituting the movement region, the control unit 100 temporarily stops the head movement motor 101 (step S105 in FIG. 24). That is, at the boundary of each region constituting the movement region of the line head 40, there is a risk that a collision sound will occur between members as the drive mechanism switches. However, by temporarily stopping the head movement motor 101 at the boundary of each region constituting the movement region, the generation of the above collision sound can be suppressed. Note that instead of temporarily stopping the head movement motor 101, the speed of the head movement motor 101 may be decreased.

[0145] The printer 1 also includes an operation unit 115, which is an example of receiving means for receiving a selection of either a speed priority mode or a normal mode as a control mode when moving the line head 40. When the speed priority mode is selected, the control unit 100 continuously drives the head movement motor 101 at the boundaries of each area constituting the movement area (step S106 in FIG. 24). When the normal mode is selected, the control unit 100 temporarily stops the head movement motor 101 at the boundaries of each area constituting the movement area (step S105 in FIG. 24).

[0146] At the boundaries of each area constituting the movement area of the line head 40, there is a possibility that a collision sound between members may occur as the drive mechanism switches. However, in the normal mode, since the head movement motor 101 is temporarily stopped at the boundaries of each area constituting the movement area of the line head 40, the occurrence of the above-described collision sound can be suppressed. Also, in the speed priority mode, since the head movement motor 101 is continuously driven at the boundaries of each area constituting the movement area of the line head 40, the throughput of the process can be improved.

[0147] Hereinafter, modifications of the above-described embodiments will be described. The above-described medium conveyance path Ta is not limited to being parallel to the X-Y plane and may have an angle with respect to the X-Y plane. Therefore, the movement direction of the line head 40 is not limited to being parallel to the Z-axis direction and may have an angle with respect to the Z-axis direction. Instead of providing the protruding portion 40a at the position where it abuts against the upstream support portion 46, it may be provided at the position where it abuts against the shutter 47.

[0148] Also, the control unit 100 may selectively use encoders used for controlling the head movement motor 101 according to the operation. For example, when performing the origin detection operation, the head movement motor 101 may be controlled based on the output signal of the linear ENC 107. After performing the origin detection operation, the head movement motor 101 may be controlled based on the output signal of the rotary ENC 103. Also, the head movement motor 101 may be controlled based on the output signal of the linear ENC 107, and when the origin is detected due to a speed reduction, the control may be switched to the control using the rotary ENC 103 during driving. By seamlessly performing the switching of the target position, that is, the conversion from the linear ENC position to the rotary ENC position during driving, deceleration, stop, and acceleration are not involved, so the throughput can be improved.

[0149] Furthermore, the present invention is not limited to the embodiments and modifications described above, and various modifications are possible within the scope of the invention described in the claims, and it goes without saying that those are also included in the scope of the present invention.

Description of Reference Numerals

[0150] 1... Inkjet printer, 2... Media storage cassette, 3... Pickup roller, 5... Feeding roller, 6... Separation roller, 8... Reversal roller, 9... First nip roller, 10... Second nip roller, 12... Media support section, 13... Feeding roller, 14... Separation roller, 15... First pair of conveying rollers, 16... Driving roller, 17... Driven roller, 19... Second pair of conveying rollers, 20... Driving roller, 20a... Rotation axis, 21... Driven roller, 22... Media detection section, 27... Third pair of conveying rollers, 28... Discharge roller pair, 29... Discharge tray, 30... Head unit, 31... Unit frame, 32, 32A, 32B... Rack members, 32a... Contact portion, 32b... Pressed portion, 32c, 32d... Guided portions, 33... Guide frame, 33a... First guide section, 33b... Second guide section, 33A, 33B... Base frames, 34... Mounting frame, 35... Link mechanism, 40... Line head, 40a... Protrusion, 41... Base, 41d... Rack section, 42... Plate member, 42a... Head surface, 42d... Opening, 43... Print head chip, 44... Nozzle, 45... Opposing section, 45a... Opening, 46... Upstream support section, 47... Shutter, 48... First moving section, 49... Second moving section, 54... Coil spring, 60... Cap unit, 61... Cap section, 61a... Elastic section, 61b... Cap body section, 62... Base section, 63... Cap spring, 65... First moving section, 66... Cam, 70... Second moving section, 71... Rack, 72... Pinion, 72a... First phase region, 73... Third moving section, 74, 74A, 74B... Rotating bodies, 75... Pushing-down section, 76... Reduction mechanism, 77... Shaft, 78... First bevel gear, 79... Second bevel gear, 80, 81, 82... Spur gears, 83... Worm wheel, 84... Cylindrical worm, 100... Control section, 101... Head movement motor, 103... Rotary encoder, 104... Rotary scale, 105... Second detection section, 107... Linear encoder, 108... Linear scale, 109... First detection section, 110... Moving means, 115... Operation section, 120... Arithmetic section, 121... Motor control section, 122... Motor driver, 123... Volatile memory, 124... Non-volatile memory, 125... Program, 126... Control parameters, Am1... First region, Am2... Second region, Am3... Third region, Hp0... Cap position, Hp1... Recording position, Hp2... Jam processing position

Claims

1. A conveyance path for conveying a medium, A recording unit for recording on the medium, the recording unit being movable in a direction advancing and retreating with respect to the conveyance path, An opposing portion disposed opposite to the recording unit, A motor which is a power source for moving the recording unit, Moving means for receiving the power of the motor and moving the recording unit, Position detection means for detecting the position of the recording unit with respect to the conveyance path, A control unit for controlling the motor, Comprising, The moving direction of the recording unit includes a vertical direction component, The position detection means, A linear scale provided along the moving direction of the recording unit, A detection unit provided on the recording unit, the first detection unit for detecting the linear scale, A linear encoder comprising, When the moving means lowers the recording unit toward the opposing portion, the moving means has a configuration that allows the motor to idle after the recording unit has been placed on the opposing portion using its own weight, The control unit grasps the position of the recording unit in the moving direction based on a change in the detection signal of the position detection means when the recording unit is placed on the opposing portion, or a change in the detection signal of the position detection means when the recording unit rises from the state of being placed on the opposing portion, A recording apparatus characterized by the above.

2. In the recording apparatus according to Claim 1, Rotation detection means for detecting the rotation of the motor is provided, The control unit grasps the position of the recording unit in the moving direction based on the detection signal of the position detection means and the detection signal of the rotation detection means, A recording apparatus characterized by the above.

3. In the recording apparatus according to Claim 2, The rotation detection means, A rotary scale provided on the output shaft of the motor, A second detection unit for detecting the rotary scale, A rotary encoder comprising, A recording apparatus characterized by the above.

4. In the recording apparatus according to Claim 3, The moving means, A cylindrical worm driven by the motor, A worm wheel that meshes with the cylindrical worm and rotates as the cylindrical worm rotates, Including, A recording apparatus characterized by the above.

5. In the recording apparatus according to Claim 1, When the control unit lowers the recording unit toward the opposing unit, the origin position of the recording unit in the moving direction is set based on the position of the recording unit at the time when the signal change of the linear encoder disappears during the rotation of the motor, or when raising the recording unit from the state where it is placed on the opposing unit, based on the position of the recording unit at the time when the signal change of the linear encoder occurs during the rotation of the motor. A recording apparatus characterized by the above.

6. In the recording apparatus according to claim 1, the recording unit includes a protruding portion that protrudes toward the opposing unit, and when the protruding portion abuts against the opposing unit, the recording unit is placed on the opposing unit by utilizing its own weight. A recording apparatus characterized by the above.

7. In the recording apparatus according to claim 1, the moving region of the recording unit includes a first region, and a second region farther from the conveyance path than the first region, and has the moving means includes a first moving portion that moves the recording unit in the first region, and a second moving portion that moves the recording unit in the second region, and is provided with the recording unit when transitioning from the first region to the second region, transitions from the state of being moved by the first moving portion to the state of being moved by the second moving portion, when transitioning from the second region to the first region, transitions from the state of being moved by the second moving portion to the state of being moved by the first moving portion, and both the first moving portion and the second moving portion are driven by the motor. A recording apparatus characterized by the above.

8. In the recording apparatus according to claim 7, the first moving portion is a cam that rotates by the power of the motor, and includes a cam that moves the recording unit by rotating while supporting the recording unit, the second moving portion includes a rack provided on the recording unit, and a pinion that meshes with the rack and moves the recording unit by rotating by the power of the motor, and is provided with A recording apparatus characterized by the above.

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