JP5874419B2 - Printing device - Google Patents

Description

  The present invention relates to a printing apparatus.

  A platen that supports various media such as paper and film; a head that prints an image by ejecting a liquid such as ink toward the medium supported by the platen; and a heating unit that dries the medium; 2. Description of the Related Art A printing apparatus such as an ink jet printer having the above is known (for example, Patent Document 1).

Japanese Patent Laying-Open No. 2005-246908

In such a printing apparatus, the platen heated by the heating unit may be deformed due to thermal expansion. As a result, the distance from the head to the medium (paper gap) may fluctuate and the print image quality may deteriorate.
The present invention has been made in view of such circumstances, and an object thereof is to suppress deformation of the platen due to thermal expansion.

The main invention for solving the above problems is:
A platen that supports the medium;
A head that prints an image by ejecting liquid toward the medium supported by the platen;
A heating unit for drying the liquid discharged toward the medium by heating the platen;
A support member that supports the platen heated by the heating unit via an elastic member;
It is a printing apparatus characterized by having.
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is a schematic sectional view of a printer 1. 2 is a block diagram illustrating a configuration example of a printer 1. FIG. It is a figure explaining the state of the platen 29 before and behind a deformation | transformation. FIG. 4A is a schematic plan view showing a configuration example 1 of the support structure that supports the platen 29. FIG. 4B is a schematic side view showing a configuration example 1 of the support structure that supports the platen 29 using the rubber member 123. 5A and 5B are enlarged views of a portion indicated by reference numeral A in FIG. 4B and are diagrams for explaining the state of the rubber member 123 before and after deformation. 6A and 6B are schematic side views showing another configuration example 2 of the support structure for supporting the platen 29, and are diagrams for explaining the state of the spring member 126 before and after deformation. 7A and 7B are schematic side views showing another configuration example 3 of the support structure for supporting the platen 29, and are diagrams for explaining the state of the rubber member 127 before and after deformation. 1 is a schematic external view of an ink jet printer. 1 is a schematic diagram illustrating a configuration of an inkjet printer 501. FIG. FIG. 5 is a schematic diagram illustrating a configuration of an inkjet head 541 and its peripheral members of the inkjet printer 501. 11A and 11B are diagrams illustrating a configuration example of the restricting unit.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.
A platen that supports the medium;
A head that prints an image by ejecting liquid toward the medium supported by the platen;
A heating unit for drying the liquid discharged toward the medium by heating the platen;
A support member that supports the platen heated by the heating unit via an elastic member;
It is a printing apparatus characterized by having.
According to such a printing apparatus, since the platen is supported by the support member via the elastic member, deformation of the platen due to thermal expansion can be suppressed by elastic deformation of the elastic member.

Moreover, it is such a printing apparatus,
The platen and the support member are provided apart from each other,
The elastic member may be disposed between the platen and the support member that are spaced apart from each other, and may have one end coupled to the platen and the other end coupled to the support member.
According to such a printing apparatus, since the elastic member is disposed between the platen and the support member that are separated from each other, the amount of deformation when the elastic member is elastically deformed can be increased.

Moreover, it is such a printing apparatus,
It is good also as having a control part which controls the separation distance between the platen and the support member.
According to such a printing apparatus, it becomes possible to regulate the fluctuation of the paper gap, so that it is possible to suppress the deterioration of the print image quality.
Moreover, it is such a printing apparatus,
The platen and the support member are provided in contact with each other,
The elastic member may be embedded between the platen and the support member that are in contact with each other, and may have one end coupled to the platen and the other end coupled to the support member.
According to such a printing apparatus, since the elastic member is embedded between the platen and the support member that are in contact with each other, the size of the paper gap is maintained, and deterioration in print image quality can be suppressed. Moreover, deformation of the platen due to thermal expansion can be suppressed by the elastic deformation of the embedded elastic member.

=== Embodiment ===
<<< Configuration Example of Printer 1 >>>
A configuration example of a printer 1 as an example of a printing apparatus (in this embodiment, an ink jet printer, in particular, a lateral scan type label printing machine) will be described with reference to FIGS. FIG. 1 is a schematic sectional view of the printer 1. FIG. 2 is a block diagram illustrating a configuration example of the printer 1.

  In the following description, when referring to “up and down direction” and “left and right direction”, the direction indicated by the arrow in FIG. 1 is used as a reference. In addition, the “front-rear direction” refers to a direction orthogonal to the paper surface in FIG.

  Further, in the present embodiment, as an example of a medium on which the printer 1 records an image, a paper wound in a roll shape (hereinafter referred to as roll paper (continuous paper)) will be described.

  As shown in FIGS. 1 and 2, the printer 1 according to the present embodiment includes a transport unit 20 and a transport path through which the transport unit 20 transports the roll paper 2 (in FIG. 1, the transport path is a roll A feed unit 10, a platen 29, and a take-up unit 90, along the paper roll shaft 18 to the roll paper take-up drive shaft 92. The head unit 30 that performs image printing by discharging a plurality of types of ink in the printing region R on the transport path, the ink supply unit 35, the carriage unit 40, the heater unit 70 as an example of a heating unit, and the platen 29 A blower unit 80 for sending wind to the upper roll paper 2, and a controller 60 for controlling these units and controlling the operation as the printer 1; It has a detector group 50, a.

  The feeding unit 10 feeds the roll paper 2 to the transport unit 20. The feeding unit 10 includes a roll paper winding shaft 18 around which the roll paper 2 is wound and rotatably supported, and a relay roller 19 for winding the roll paper 2 fed from the roll paper winding shaft 18 and guiding the roll paper 2 to the transport unit 20. And have.

  The transport unit 20 transports the roll paper 2 sent by the feeding unit 10 along a preset transport path. As shown in FIG. 1, the transport unit 20 includes a relay roller 21 that is positioned horizontally to the right of the relay roller 19, a relay roller 22 that is positioned obliquely downward to the right when viewed from the relay roller 21, and the relay roller 22. A first conveyance roller 23 located obliquely right above (as viewed from the platen 29 in the conveyance direction), and a steering unit (steering unit) 20a positioned between the relay roller 22 and the first conveyance roller 23, A second transport roller 24 positioned on the right side (downstream in the transport direction as viewed from the platen 29) as viewed from the first transport roller 23, a reversing roller 25 positioned vertically downward as viewed from the second transport roller 24, A relay roller 26 located on the right side when viewed from the reversing roller 25, a delivery roller 27 positioned above when viewed from the relay roller 26, It has.

  The relay roller 21 is a roller that winds the roll paper 2 sent from the relay roller 19 from the left side and loosens it downward.

  The relay roller 22 is a roller that winds the roll paper 2 sent from the relay roller 21 from the left side and conveys it obliquely upward to the right.

  The first transport roller 23 includes a first drive roller 23a driven by a motor (not shown), and a first driven roller 23b arranged to face the first drive roller 23a with the roll paper 2 interposed therebetween. have. The first transport roller 23 is a roller that pulls up the roll paper 2 slacked downward and transports it to the printing region R facing the platen 29. The first transport roller 23 is configured to temporarily stop transport during a period in which image printing is performed on a portion of the roll paper 2 on the print region R. In addition, the conveyance amount of the roll paper 2 positioned on the platen 29 is adjusted by rotating the first driven roller 23b in accordance with the rotational drive of the first drive roller 23a by the drive control of the controller 60.

  As described above, the transport unit 20 has a mechanism for transporting the portion of the roll paper 2 wound between the relay rollers 21 and 22 and the first transport roller 23 by slacking it downward. The slackness of the roll paper 2 is monitored by the controller 60 based on a detection signal from a slack detection sensor (not shown). Specifically, when a portion of the roll paper 2 slackened between the relay rollers 21 and 22 and the first transport roller 23 is detected by the slack detection sensor, a tension of an appropriate magnitude is applied to the portion. Therefore, the transport unit 20 can transport the roll paper 2 in a relaxed state. On the other hand, when the portion of the roll paper 2 that has been loosened is not detected by the slack detection sensor, an excessive amount of tension is applied to the portion, so that the roll paper 2 is transported by the transport unit 20. It is temporarily stopped and the tension is adjusted to an appropriate magnitude.

  As shown in FIG. 1, the steering unit 20a is positioned on the conveyance path in an inclined state, and rotates to roll paper 2 in the width direction position (width direction (front-back direction shown in FIG. 1)) of the roll paper 2. This is for changing the position at which is located. That is, when the roll paper 2 is conveyed along the conveyance path, the tension applied to the roll paper 2 fluctuates due to an axial deviation or an assembly error of a relay roller or the like. The position may be displaced. The steering unit 20 a is for adjusting the position in the width direction of the roll paper 2.

  The second transport roller 24 includes a second drive roller 24a driven by a motor (not shown), and a second driven roller 24b disposed so as to face the second drive roller 24a with the roll paper 2 interposed therebetween. have. The second transport roller 24 is a roller that transports the portion of the roll paper 2 on which the image is recorded by the head unit 30 in the horizontal right direction along the support surface of the platen 29 and then transports it vertically downward. Thereby, the conveyance direction of the roll paper 2 is changed. The second driven roller 24b rotates as the second drive roller 24a is driven to rotate by the drive control of the controller 60, whereby a predetermined amount given to the portion of the roll paper 2 located on the platen 29 is obtained. Tension is adjusted.

  The reversing roller 25 is a roller that wraps the roll paper 2 sent from the second conveying roller 24 from the upper left side and conveys it diagonally upward to the right.

  The relay roller 26 is a roller that winds the roll paper 2 sent from the reversing roller 25 from the lower left side and conveys it upward.

  The delivery roller 27 winds the roll paper 2 sent from the relay roller 26 from the lower left side and sends it to the take-up unit 90.

  As described above, the roll paper 2 moves sequentially through the rollers, whereby a transport path for transporting the roll paper 2 is formed. The roll paper 2 is intermittently conveyed along the conveyance path by the conveyance unit 20 in units of areas corresponding to the printing areas R.

  The head unit 30 is for recording an image on a portion of the roll paper 2 located in the printing region R on the transport path. That is, the head unit 30 forms an image by ejecting ink from the ink ejection nozzles onto the portion of the roll paper 2 that has been fed into the printing region R (on the platen 29) on the transport path by the transport unit 20. In the present embodiment, the head unit 30 has M heads 31.

  Each head 31 has an ink discharge nozzle row in which ink discharge nozzles are arranged in the row direction on the lower surface (that is, the nozzle surface). In the present embodiment, there is an ink discharge nozzle row composed of a plurality of ink discharge nozzles # 1 to #N for each color such as yellow (Y), magenta (M), cyan (C), and black (K). doing. The ink discharge nozzles # 1 to #N of each ink discharge nozzle row are linearly arranged in a cross direction that intersects the transport direction of the roll paper 2 (that is, the cross direction is the above-described row direction). . The respective ink discharge nozzle rows are arranged in parallel with a space therebetween along the transport direction.

  Each of the ink discharge nozzles # 1 to #N is provided with a piezo element (not shown) as a drive element for discharging ink droplets. When a voltage having a predetermined time width is applied between the electrodes provided at both ends of the piezoelectric element, the piezoelectric element expands according to the voltage application time and deforms the side wall of the ink flow path. As a result, the volume of the ink flow path contracts according to the expansion and contraction of the piezo element, and the ink corresponding to the contraction is ejected from the ink ejection nozzles # 1 to #N of the respective colors as ink droplets.

  Then, M such heads 31 are arranged in the intersecting direction (the row direction), thereby forming the head unit 30. Therefore, the head unit 30 has M × N ink ejection nozzles for each color.

  The ink supply unit 35 is for supplying ink to the head unit 30 when the amount of ink in the head unit 30 decreases due to ink ejection by the head 31.

  The ink supply unit 35 is provided for each ink color. That is, a yellow ink supply unit for supplying yellow ink, a magenta ink supply unit for supplying magenta ink, a cyan ink supply unit for supplying cyan ink, and a black ink supply For this purpose, a black ink supply unit or the like is provided.

  The ink supply unit 35 includes an ink cartridge, a large number of tubes serving as ink flow paths (passages), a large number of valves for opening and closing the tubes, and the like. The place where the ink cartridge is installed is indicated by reference numeral 35 in FIG.

  The carriage unit 40 is for moving the head unit 30 (head 31). The carriage unit 40 is supported by a carriage guide rail 41 (indicated by a two-dot chain line in FIG. 1) extending in the transport direction (left-right direction) and reciprocally movable along the carriage guide rail 41 in the transport direction (left-right direction). A carriage 42 and a motor (not shown).

  The carriage 42 is provided with a head unit 30 (head 31). The carriage 42 is configured to move in the transport direction (left-right direction) together with the head unit 30 (head 31) by driving a motor (not shown). When the head unit 30 (head 31) is cleaned after image printing, the carriage 42 is integrated with the head unit 30 (head 31) along the carriage guide rail 41 on the upstream side (from the platen 29). It moves to the upstream side in the transport direction as viewed, and stops at the home position HP for cleaning (see FIG. 1).

  Further, a flushing unit 44 is provided between a home position (hereinafter referred to as HP; see FIG. 1) in the transport direction (left and right direction) and the platen 29, and the head 31 (carriage 42) moves in the transport direction ( When the head 31 moves to the left and right and faces the flushing unit 44, the head 31 performs a flushing operation for performing flushing by ejecting ink from each ink ejection nozzle belonging to the ink ejection nozzle row.

  The platen 29 supports the part of the roll paper 2 located in the printing region R on the conveyance path and heats the part. As shown in FIG. 1, the platen 29 is provided in correspondence with the printing region R on the conveyance path, and in a region along the conveyance path between the first conveyance roller 23 and the second conveyance roller 24. Has been placed. The platen 29 can heat the portion of the roll paper 2 by receiving supply of heat generated by the heater unit 70.

  The heater unit 70 is for heating the roll paper 2 and has a heater 71. The heater 71 has a nichrome wire, and the nichrome wire is arranged inside the platen 29 so as to be a fixed distance from the support surface of the platen 29. For this reason, when the heater 71 is energized, the nichrome wire itself generates heat and can conduct heat to the portion of the roll paper 2 located on the support surface of the platen 29. Since the heater 71 is configured by incorporating a nichrome wire in the entire area of the platen 29, it can conduct heat uniformly to the portion of the roll paper 2 on the platen 29. In the present embodiment, the portion of the roll paper 2 is uniformly heated so that the temperature of the portion of the roll paper 2 on the platen is 45 ° C. Thereby, the ink landed on the part of the roll paper 2 can be dried.

  The blower unit 80 is for sending wind to the roll paper 2 on the platen 29. The blower unit 80 includes a fan 81 and a motor (not shown) that rotates the fan 81. The fan 81 rotates to send wind to the roll paper 2 on the platen 29 and dry the ink landed on the roll paper 2. As shown in FIG. 1, a plurality of fans 81 are provided on an openable / closable cover (not shown) provided on the main body. Each fan 81 is positioned above the platen 29 when the cover is closed, and faces the support surface of the platen 29 (the roll paper 2 on the platen 29).

  The winding unit 90 is for winding the roll paper 2 (image-printed roll paper) sent by the transport unit 20. This take-up unit 90 is fed from the relay roller 91 that is rotatably supported by the relay roller 91 for winding the roll paper 2 sent from the feed roller 27 from the upper left side and conveying it to the lower right side. A roll paper take-up drive shaft 92 for taking up the roll paper 2.

  The controller 60 is a control unit for controlling the printer 1. As shown in FIG. 2, the controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 is for transmitting and receiving data between the computer 110 which is an external device and the printer 1. The CPU 62 is an arithmetic processing unit for controlling the entire printer 1. The memory 63 is for securing an area for storing a program of the CPU 62, a work area, and the like. The CPU 62 controls each unit by a unit control circuit 64 according to a program stored in the memory 63.

  The detector group 50 is for monitoring the situation in the printer 1. For example, the above-described slack detection sensor, a rotary encoder attached to the conveyance roller and used for controlling the conveyance of the roll paper 2, and the like A paper detection sensor for detecting the presence or absence of the roll paper 2 to be detected, a linear encoder for detecting the position of the carriage 42 (or head 31) in the transport direction (left-right direction), and a paper edge (edge) in the width direction of the roll paper 2 ) There is a paper edge position detection sensor that detects the position.

<<< Supporting Structure of Platen 29 >>>
<About thermal expansion>
Here, the thermal expansion of the platen 29 will be described with reference to FIG. FIG. 3 is a diagram illustrating the state of the platen 29 before and after deformation.

  In the printer 1, the portion of the roll paper 2 supported on the platen 29 is heated by the heater unit 70 (heater 71) via the platen 29 in order to improve the fixability of the ink that has landed on the roll paper 2 during printing. ing. For this reason, as shown in FIG. 3, when the platen 29 and the support frame 121 are completely fixed by the screws 122 at a plurality of locations, the platen 29 is heated and thermally expanded, whereby the roll paper 2 in the platen 29 is removed. The supporting surface may be deformed so as to wave between the screws. As a result, the distance PG (paper gap PG) from the lower surface (nozzle surface) of the head 31 to the printing surface of the roll paper 2 (upper surface of the platen 29) varies. Even if ejection is performed at an appropriate timing, the dots are landed out of the target position on the roll paper 2. When the dot formation position deviates from the target position in this way, the image quality of the print image formed on the roll paper 2 is deteriorated.

Therefore, in the printer 1 of the present embodiment, the platen 29 and the support frame 121 are not completely supported by the screws 122, and even if the platen 29 is heated and thermally expanded, the thermal expansion is absorbed. It was decided to adopt a support structure capable of Thereby, deformation of the platen 29 due to thermal expansion can be suppressed.
Below, the support structure of the platen 29 will be specifically described.

<Configuration Example 1 of Support Structure>
First, structural example 1 of the support structure for supporting the platen 29 will be described with reference to FIGS. 4A, 4B, 5A, and 5B. FIG. 4A is a schematic plan view showing a support structure for the platen 29. FIG. 4B is a schematic side view showing a support structure for the platen 29. 5A and 5B are enlarged views of a portion indicated by reference numeral A in FIG. 4B and are diagrams for explaining the state of the rubber member 123 before and after deformation.

  4A and 4B, the platen 29 is heated by a heater 71 and supported by a support frame 121 as an example of a support member via a rubber member 123 as an example of an elastic member. Each of the front end and the rear end of the platen 29 is formed with a plurality of circular upper support holes 124 penetrating vertically in a plan view so as to face each other in the front-rear direction and to be arranged at equal intervals in the left-right direction. ing.

  As shown in FIG. 5A, the upper support hole 124 of the platen 29 has a large hole portion 124a on the upper side with a substantially center in the vertical direction as a boundary, and is a small hole as a through hole having a smaller inner diameter than the large hole portion 124a. A portion 124b is provided on the lower side. The upper support hole 124 has a step surface 124c between the large hole portion 124a and the small hole portion 124b. The step surface 124c is a support surface (upper surface) for supporting the roll paper 2 in the platen 29. It is a horizontal plane parallel to.

  As shown in FIGS. 4B and 5A, the support frame 121 is disposed on the lower side of the platen 29 and has a circular lower support penetrating in the vertical direction at positions facing the upper support holes 124 of the platen 29. A hole 125 is provided.

  As shown in FIG. 5A, the lower support hole 125 of the support frame 121 has a large hole portion 125a on the lower side, with a substantially center in the vertical direction as a boundary, and serves as a through hole having a smaller inner diameter than the large hole portion 125a. A small hole 125b is provided on the upper side. The lower support hole 125 has a step surface 125 c between the large hole portion 125 a and the small hole portion 125 b, and the step surface 125 c is a horizontal plane parallel to the lower surface of the support frame 121.

  As shown in FIGS. 5A and 5B, the rubber member 123 is disposed between the platen 29 and the support frame 121 that are spaced apart from each other. When the platen 29 is heated and thermally expanded, the rubber member 123 is elastically deformed to be elastically deformed. By absorbing the thermal expansion, it is possible to suppress deformation of the platen 29 due to thermal expansion (a wave-like deformation between the screws). The rubber member 123 is formed in a columnar shape, and its upper end portion 123a is brought into contact with the lower surface of the platen 29 and its lower end portion 123b is brought into contact with the upper surface of the support frame 121. A space is formed between the terminal 121 and the terminal 121. By providing this space between the platen 29 and the support frame 121, even when the amount of deformation when the rubber member 123 is elastically deformed in the horizontal direction is large, it is possible to cope (see FIG. 5B). The rubber member 123 has a metal female screw portion 123c having a female screw hole formed on the inner peripheral surface at the upper end portion 123a on the platen 29 side and the lower end portion 123b on the support frame 121 side. Since the female screw portion 123c is bonded, it is integrated with the main body of the rubber member 123. Therefore, when a screw 122 as an example of a fastening member is inserted into the upper support hole 124 of the platen 29 from above, the shaft portion 122b of the screw 122 is inserted into the small hole portion 124b and the outer periphery of the shaft portion 122b of the screw 122 is inserted. The male screw portion 122 c formed on the surface is screwed to the female screw portion 123 c of the upper end portion 123 a of the rubber member 123. As a result, the lower surface of the head portion 122a of the screw 122 is pressed against the stepped surface 124c of the upper support hole 124, and the upper end portion 123a of the rubber member 123 is pressed against the lower surface of the platen 29. Will be combined. On the other hand, when the screw 122 is inserted into the lower support hole 125 of the support frame 121 from below, the shaft portion 122b of the screw 122 is inserted into the small hole portion 125b and formed on the outer peripheral surface of the shaft portion 122b of the screw 122. The male screw portion 122 c thus formed is screwed into the female screw portion 123 c of the lower end portion 123 b of the rubber member 123. As a result, the lower surface of the head 122a of the screw 122 is in pressure contact with the step surface 125c of the lower support hole 125, and the lower end 123b of the rubber member 123 is in pressure contact with the upper surface of the support frame 121. 123 will be combined.

  In this way, the platen 29 and the support frame 121 are coupled via the rubber member 123, so that the platen 29 and the support frame 121 are not completely fixed by the screws 122. Therefore, even if the platen 29 is heated and thermally expanded, the rubber member 123 is elastically deformed, so that the platen 29 is deformed in the horizontal direction while preventing the platen 29 from being raised and waved between the screws in a vertical direction. Therefore, it becomes possible to absorb the thermal expansion (see FIG. 5B).

<Configuration Example 2 of Support Structure>
Next, another configuration example 2 of the support structure for supporting the platen 29 will be specifically described with reference to FIGS. 6A and 6B. 6A and 6B are schematic side views showing another configuration example 2 of the support structure for supporting the platen 29, and are diagrams for explaining the state of the spring member 126 before and after deformation.

  As described above, the configuration example 1 of the support structure of the platen 29 is the support structure in which the platen 29 is supported by the support frame 121 via the rubber member 123, whereas the other configuration example 2 of the support structure of the platen 29 is provided. The difference is that the platen 29 is supported by the support frame 121 via the spring member 126. Therefore, in the following, a different part from the configuration example 1 of the support structure will be described.

  As shown in FIGS. 6A and 6B, the spring member 126 is disposed between the platen 29 and the support frame 121 which are spaced apart from each other. When the platen 29 is heated and thermally expanded, the spring member 126 is elastically deformed to be elastically deformed. By absorbing the thermal expansion, it is possible to suppress deformation of the platen 29 due to thermal expansion (a wave-like deformation between the screws). The spring member 126 has a coiled compression spring, an upper end portion 126a to which one end of the compression spring is welded, and a lower end portion 126b to which the other end of the compression spring is welded. The spring member 126 has a space between the platen 29 and the support frame 121 by bringing the upper end 126 a into contact with the lower surface of the platen 29 and bringing the lower end 126 b into contact with the upper surface of the support frame 121. Is forming. By providing this space between the platen 29 and the support frame 121, even when the amount of deformation when the spring member 126 is elastically deformed in the horizontal direction is large, this can be handled (see FIG. 6B). The spring member 126 has a female screw portion 126c having a female screw hole formed in the inner peripheral surface at the upper end portion 126a on the platen 29 side and the lower end portion 126b on the support frame 121 side. Therefore, when the screw 122 is inserted into the upper support hole 124 of the platen 29 from the upper side, the shaft portion 122b of the screw 122 is inserted into the small hole portion 124b, and the male portion formed on the outer peripheral surface of the shaft portion 122b of the screw 122. The screw portion 122c is screwed into the female screw portion 126c of the upper end portion 126a of the spring member 126. As a result, the lower surface of the head portion 122a of the screw 122 is pressed against the stepped surface 124c of the upper support hole 124, and the upper end portion 126a of the spring member 126 is pressed against the lower surface of the platen 29. Will be combined. On the other hand, when the screw 122 is inserted into the lower support hole 125 of the support frame 121 from below, the shaft portion 122b of the screw 122 is inserted into the small hole portion 125b and formed on the outer peripheral surface of the shaft portion 122b of the screw 122. The male screw portion 122 c thus formed is screwed into the female screw portion 126 c of the lower end portion 126 b of the spring member 126. As a result, the lower surface of the head 122a of the screw 122 is in pressure contact with the step surface 125c of the lower support hole 125, and the lower end 126b of the spring member 126 is in pressure contact with the upper surface of the support frame 121. 126 will be coupled.

  In this manner, the platen 29 and the support frame 121 are coupled via the spring member 126, so that the platen 29 and the support frame 121 are not completely fixed by the screws 122. For this reason, even if the platen 29 is heated and thermally expanded, the spring member 126 is elastically deformed, so that the platen 29 is deformed in the horizontal direction while preventing the platen 29 from being raised and waved between the screws in a vertical direction. Therefore, it becomes possible to absorb the thermal expansion (see FIG. 6B).

<Configuration Example 3 of Support Structure>
Next, another configuration example 3 of the support structure for supporting the platen 29 will be specifically described with reference to FIGS. 7A and 7B. 7A and 7B are schematic side views showing another configuration example 3 of the support structure for supporting the platen 29, and are diagrams for explaining the state of the rubber member 127 before and after deformation.

  As described above, in the configuration example 1 and the other configuration example 2 of the support structure of the platen 29, the rubber member 123 or the spring member 126 is disposed between the platen 29 and the support frame 121 which are separated from each other, and the rubber member 123 or While the platen 29 is supported by the support frame 121 via the spring member 126, in the other configuration example 3 of the platen 29 support structure, the rubber member is interposed between the platen 29 and the support frame 121 that are in contact with each other. The support structure is such that 127 is embedded and the platen 29 is supported by the support frame 121 via the rubber member 127. Therefore, in the following description, portions different from the structural example 1 and the other structural example 2 of the support structure will be described.

  As shown in FIG. 7A, the platen 29 is supported by a support frame 121 as an example of a support member via a rubber member 127 as an example of an elastic member. Each of the front end and the rear end of the platen 29 is formed with a plurality of circular upper support holes 124 penetrating vertically in a plan view so as to face each other in the front-rear direction and to be arranged at equal intervals in the left-right direction. ing.

  As shown in FIG. 7A, the upper support hole 124 of the platen 29 has a large hole portion 124a on the upper side with a substantially vertical center as a boundary, and a small hole as a through hole having a smaller inner diameter than the large hole portion 124a. A portion 124b is provided on the lower side. The upper support hole 124 has a step surface 124c between the large hole portion 124a and the small hole portion 124b. The step surface 124c is a support surface (upper surface) for supporting the roll paper 2 in the platen 29. It is a horizontal plane parallel to.

  As shown in FIG. 7A, the support frame 121 is disposed on the lower side of the platen 29 and has lower support holes 128 that are circular in plan view corresponding to the upper support holes 124 of the platen 29. A rubber member 127 formed in a columnar shape is embedded in the lower support hole 128 with a slight gap so as to absorb the thermal expansion of the platen 29.

  As shown in FIG. 7A, the rubber member 127 is embedded between the platen 29 and the support frame 121 that are in contact with each other, and when the platen 29 is heated and thermally expanded, the rubber member 127 is elastically deformed to be thermally expanded. By absorbing this, deformation of the platen 29 due to thermal expansion (deformation that undulates between the screws) can be suppressed. The rubber member 127 has its upper end 123 a in contact with the lower surface of the platen 29 and its lower end 123 b in contact with the bottom surface of the lower support hole 128 of the support frame 121. Therefore, the lower surface of the platen 29 and the upper surface of the support frame 121 can be brought into contact with each other without forming a space between the platen 29 and the support frame 121. By bringing the platen 29 and the support frame 121 into contact with each other without being separated from each other in this manner, the amount of deformation when the spring member 127 is elastically deformed in the horizontal direction is limited to a small size, but the size of the paper gap PG is constant. Since the size can be stabilized, it is possible to suppress a decrease in print image quality (see FIG. 7B). The rubber member 127 has a metal female screw portion 127 c having a female screw hole formed on the inner peripheral surface at the upper end portion 127 on the platen 29 side. Since the female screw portion 127c is bonded, it is integrated with the main body of the rubber member 127. Therefore, when the screw 122 is inserted into the upper support hole 124 of the platen 29 from the upper side, the shaft portion 122b of the screw 122 is inserted into the small hole portion 124b, and the male portion formed on the outer peripheral surface of the shaft portion 122b of the screw 122. The screw portion 122c is screwed into the female screw portion 127c of the upper end portion 127a of the rubber member 127. As a result, the lower surface of the head portion 122a of the screw 122 is pressed against the stepped surface 124c of the upper support hole 124, and the upper end portion 127a of the rubber member 127 is pressed against the lower surface of the platen 29, whereby the platen 29, the rubber member 127, and Will be combined. On the other hand, since the rubber member 127 is fixed so as to be integrated with the support frame 121, the rubber member 127 is coupled to the support frame 121 at the lower end portion 127b.

  In this way, the platen 29 and the support frame 121 are coupled via the rubber member 127, so that the platen 29 and the support frame 121 are not completely fixed by the screws 122. Therefore, even if the platen 29 is heated and thermally expanded, the rubber member 127 is elastically deformed, and the platen 29 is deformed in the horizontal direction while suppressing the platen 29 from being deformed so as to rise up and down between the respective screws. Therefore, it becomes possible to absorb the thermal expansion (see FIG. 7B).

<<< Operation Example of Printer 1 >>>
The overall operation of the printer 1 will be described. In the printer 1 according to the present embodiment, the controller 60 is controlled according to a computer program stored in the memory 63 (feed unit 10, transport unit 20, head unit 30, ink supply unit 35, carriage unit 40, heater unit). 70, the blower unit 80, and the winding unit 90) are controlled to perform each process. Therefore, this computer program has a code for controlling a control target in order to execute these processes.

  Specifically, in the printing process, the controller 60 performs reception of a print command, paper feed operation, dot formation operation, drying operation, transport operation, paper discharge determination, and print end determination. Each process will be briefly described below.

  The reception of the print command is a process for receiving a print command from the computer 110. In this process, the controller 60 receives a print command via the interface unit 61.

  The paper feeding operation is an operation in which the roll paper 2 to be printed is moved along the transport path and positioned at a printing start position (so-called cueing position). In this operation, the controller 60 moves the roll paper 2 by driving the transport motor.

  The dot forming operation is an operation for forming dots on the roll paper 2. In this operation, the controller 60 drives the carriage 42 and outputs a control signal to the head 31. At this time, a drive signal is applied to the piezo element, whereby ink is ejected from each nozzle. Accordingly, ink is intermittently discharged from each nozzle while the head 31 is moving, and dots are formed on the roll paper 2.

  The drying operation is an operation for drying the dots formed on the roll paper 2. The controller 60 operates the heater 71 or rotates the fan 81 to dry the dots formed on the roll paper 2.

  The transport operation is an operation for moving the roll paper 2 intermittently in the transport direction. The controller 60 can form dots at positions different from the dots formed by the previous dot formation operation by driving the carry motor.

  The print end determination is a determination as to whether or not to continue printing. The controller 60 makes a print end determination based on the presence or absence of print data for the roll paper 2 to be printed.

<<< Effectiveness of Printer 1 According to the Present Embodiment >>>
As described above, the printer 1 according to the present embodiment includes the platen 29 that supports the roll paper 2, the head 31 that ejects ink toward the roll paper 2 supported by the platen 29, and the platen 29. A heater unit 70 that dries the ink ejected toward the roll paper 2 and a support frame that supports the platen 29 heated by the heater unit 70 via a rubber member 123. ing. Therefore, when the platen 29 heated by the heater unit 70 is thermally expanded, the rubber member 123 is elastically deformed, thereby suppressing the platen 29 from being deformed so as to rise up and down between the respective screws and undulate. Since it can be deformed in the horizontal direction, it is possible to absorb the thermal expansion.

  In addition, the platen 29 and the support frame 121 are provided apart from each other, and the rubber member 123 is disposed between the platen 29 and the support frame 121 that are separated from each other, and an upper end portion 123 a that is coupled to the platen 29 and the support frame 121. And a lower end 123b coupled to the. As described above, since the rubber member 123 is disposed between the platen 29 and the support frame 121 which are separated from each other, when the rubber member 123 is elastically deformed by heating and thermal expansion of the platen 29, the rubber member 123 Even when the amount of deformation is large, the thermal expansion of the platen 29 can be absorbed.

  The platen 29 and the support frame 121 are provided in contact with each other, and the rubber member 127 is embedded between the platen 29 and the support frame 121 in contact with each other, and an upper end portion 127 a coupled to the platen 29 and the support frame 121. And a lower end portion 127b coupled to the. Thus, since the rubber member 127 is embedded between the platen 29 and the support frame 121 that are in contact with each other, even when the platen 29 is heated and thermally expanded, the rubber member 127 is elastically deformed to heat the platen 29. The expansion can be absorbed, and the size of the paper gap PG can be stabilized, so that it is possible to suppress a decrease in print image quality.

=== Other Embodiments ===
This embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<Printing device>
In the above embodiment, the lateral scanning type label printing machine has been described as an example of the printing apparatus. However, the present invention is not limited to this, and for example, a serial scanning type large format printer may be used.

  The serial scan type large format printer (hereinafter referred to as an inkjet printer 501) will be described below with reference to FIGS. FIG. 8 is a schematic external view of the ink jet printer 501. FIG. 9 is a schematic diagram illustrating a configuration of the inkjet printer 501. FIG. 10 is a schematic diagram showing the configuration of the inkjet head 541 and its peripheral members of the inkjet printer 501.

  As shown in FIGS. 8 to 10, the ink jet printer 501 includes a printer main body 502 having an ink jet head 541 (described later) and a support stand 503 that supports the printer main body 502. The ink jet printer 501 basically has a platen 551 that supports the roll paper R, a support means 526 that has a support frame 552 that supports the platen 551, and an ink jet head 541 that is supported on the platen 551. Printing means 521 for printing on the rolled paper R, feed means for feeding the roll paper R along the feed path, ink supply means 523 having an ink cartridge 581 for supplying ink to the ink jet head 541, and ink jet A maintenance means 524 for maintenance of the head 541 and a control means 525 for controlling the entire ink jet printer 501 by controlling these means in association with each other are provided. Then, an image is printed on the roll paper R supported on the platen 551 by driving the printing unit 521 and the feeding unit synchronously while supplying ink to the inkjet head 541 by the ink supply unit 523. ing. The printing unit 521 includes a head unit 531 on which an inkjet head 541 is mounted, and a head moving mechanism 532 that supports the head unit 531 in a movable manner and moves the head unit 531.

  The head moving mechanism 532 is disposed on the opposite side of the platen 551 with the roll paper R interposed therebetween, and reciprocates the inkjet head 541 positioned opposite to the platen 551 within a preset head moving region 564. It is configured. In the present embodiment, the position corresponding to the right end of the head movement area 564 in the figure is set as the home position of the head unit 531, and the movement position of the head unit 531 is grasped using this position as a reference position. The platen 551 is provided with a heater unit (not shown). By uniformly heating the portion of the roll paper R on the platen 551, the ink landed on the portion of the roll paper R can be dried. . The platen 551 is supported by the support frame 552 via an elastic member (not shown). For the support structure of the platen 551, the same configuration example as the support structure according to the above-described embodiment can be used. Therefore, even if the platen 551 is heated and thermally expanded, it is possible to suppress deformation of the platen 29 due to thermal expansion (deformation that undulates between the screws) due to elastic deformation of the elastic member.

<Adjustment screw>
In the printer 1 according to the above-described embodiment, when the support structure for the platen 29 shown in the configuration example 1 and the configuration example 2 is adopted, a regulation unit that regulates the separation distance between the platen 29 and the support frame 121 is provided. Also good. This will be specifically described below.

  11A and 11B are diagrams illustrating a configuration example of the adjusting screw 130 as an example of a restricting portion. The adjustment screw 130 has a head portion 130a and a shaft portion 130b. The shaft part 130b has a male screw part 130c formed on the outer peripheral surface thereof, and a tip part 130d formed on the tip. The support frame 121 is formed with a female screw hole 125d penetrating vertically.

  As shown in FIG. 11A, the male screw portion 130c of the adjustment screw 130 is screwed into the female screw hole 125d of the support frame 121 by screwing the shaft portion 130b of the adjustment screw 130 from the lower side of the female screw hole 125d. Match. In this way, the tip 130d of the adjustment screw 130 can be positioned in the space between the platen 29 and the support plate 121. The length of the shaft portion 130b of the adjustment screw 130 protruding from the upper surface of the support frame 121 can be adjusted by screwing or screwing the shaft portion 130b of the adjustment screw 130.

  Further, as shown in FIG. 11A, the adjustment screw 130 is locked to the female screw hole 125d at a position below the support frame 121 in the shaft portion 130b of the adjustment screw 130 so that the adjustment screw 130 does not advance or retract. For this purpose, a locking nut 131 is screwed. Then, by rotating the lock nut 131 so as to be in pressure contact with the lower surface of the support frame 121, the movement of the shaft portion 130b of the adjustment screw 130 in the vertical direction can be restricted.

  Here, when the heated platen 29 is thermally expanded, a horizontal stress is applied to the rubber member 123, and the rubber member 123 is elastically deformed. When the rubber member 123 is elastically deformed, as shown in FIG. 11B, the distal end portion 130d of the adjustment screw 130 comes into contact with the lower surface of the support frame 121, so that the separation distance L between the platen 29 and the support frame 121 is restricted. . Thereby, since the size of the paper gap PG after the deformation can be stabilized to a constant size, it is possible to suppress a decrease in print image quality.

  As shown in FIG. 11B, the tip 130d of the adjusting screw 130 is formed in a spherical shape, so that it makes point contact with the lower surface of the thermally expanded platen 29. For this reason, when the platen 29 is thermally expanded, the platen 29 can be slid in a state where the lower surface of the platen 29 is in contact with the tip portion 130d of the adjusting screw 130, so that the load received at the contact portion of the lower surface can be reduced.

<Others>
Moreover, in the said embodiment, although the roll paper 2 was mentioned as an example and demonstrated as a medium, it is not limited to this, For example, a cut paper, a film, and cloth may be sufficient.

  In the above embodiment, the head unit 30 has a plurality of (M) heads 31. However, the present invention is not limited to this. For example, the head unit 30 may be composed of one head 31.

DESCRIPTION OF SYMBOLS 1 Printer 2 Roll paper 10 Feeding unit 18 Roll paper winding shaft 19 Relay roller 20 Transport unit 20a Steering unit 21 Relay roller 22 Relay roller 23 First transport roller 23a First drive roller 23b First driven roller 24 Second transport roller 24a First Double drive roller 24b Second driven roller 25 Reverse roller 26 Relay roller 27 Delivery roller 29 Platen 30 Head unit 31 Head 35 Ink supply unit 40 Carriage unit 41 Guide rail 42 Carriage 50 Detector group 60 Controller 61 Interface unit 62 CPU
63 Memory 64 Unit control circuit 70 Heater unit 80 Blower unit 81 Fan 90 Winding unit 91 Relay roller 92 Roll paper winding drive shaft 110 Computer 121 Support frame 122 Screw 122a Head 122b Shaft portion 122c Male screw portion 123 Rubber member 123a Upper end portion 123b Lower end portion 123c Female screw portion 124 Upper support hole 124a Large hole portion 124b Small hole portion 124c Stepped surface 125 Lower support hole 125a Large hole portion 125b Small hole portion 125c Stepped surface 125d Female screw hole 126 Spring member 126a Upper end portion 126b Lower end portion 126c Female thread part 127 Rubber member 127a Upper end part 127b Lower end part 127c Female thread part 128 Lower support hole 130 Adjustment screw 130a Head part 130b Shaft part 130c Male thread part 130d Tip part 131 Lock Nut 501 Inkjet Printer 502 Printer Main Body 503 Support Stand 521 Printing Means 523 Ink Supply Means 524 Maintenance Means 525 Control Means 526 Support Means 531 Head Unit 532 Head Movement Mechanism 541 Inkjet Head 551 Platen 552 Support Frame 564 Head Movement Area 581 Ink cartridge

Claims (1)

A platen that supports the medium;
A head that prints an image by ejecting liquid toward the medium supported by the platen;
A heating unit for drying the liquid discharged toward the medium by heating the platen;
A support member that supports the platen heated by the heating unit via an elastic member;
Equipped with a,
The platen and the support member are provided in contact with each other,
The elastic member is embedded between the platen and the support member in contact with each other, and
And one end portion for coupling to the platen, the printing apparatus characterized in that it have a, and the other end portion for coupling to the support member.