JP5329026B2 - Inkjet printer - Google Patents

Description

  The present invention is disposed above a support member that supports a portion to be printed on a print medium so as to be capable of reciprocating in a direction orthogonal to the conveyance direction of the print medium, and has ink ejection holes that are vertically opposed to the support member. The present invention relates to an ink jet printer including the head device.

  The above-described ink jet printer is configured to perform printing by ejecting ink from ink ejection holes onto a print medium supported by a support member while moving the head device. An ink jet printer may be provided with a housing that houses a support member and a head device and has a discharge port for discharging a print medium from the support member. A form in which the operation is performed in an enclosed space is known. Further, the ink jet printer is provided with a maintenance device that is positioned on one end side in the moving direction of the head device with respect to the support member and positioned below the head device and forcibly sucks ink from the ink ejection holes. By sucking ink by the maintenance device, clogging and drying of the ink ejection holes are eliminated, and a state where ink is normally ejected from the ink ejection holes can be maintained.

  In addition, the printed matter obtained by the ink jet printer is in a finished state after the ink is ejected onto the print medium, the liquid component of the ink evaporates and the colorant remains on the print medium and is fixed. As a method for bringing a printed product into a finished state at an early stage, the ink can be dried at an early stage. Conventionally, a plurality of fans for forcibly drying the ink ejected onto the printing medium have been provided near the discharge port. An ink jet printer is known (see, for example, Patent Document 1). These fans are arranged and fixed side by side in the moving direction of the head device, and air is blown over the entire range of the moving direction of the head device to the print medium ejected and ejected from the support member. It comes to spray.

Japanese Patent Publication No. 2005-349632

  By the way, when the ink permeability of the printing medium is low, printing may be performed using ink containing a highly volatile liquid component. At this time, the liquid component volatilized immediately after the ink is ejected is the head. There was a risk of condensation on the equipment. In particular, in the form in which the support member and the head device are accommodated in the housing, the atmosphere in the peripheral region of the head device is easily saturated with a volatilized liquid component, and such condensation is likely to occur. When condensation occurs in the head device, the ink ejection holes are clogged, and ink is not ejected normally, resulting in a decrease in printing performance.

  Further, according to the conventional form, a plurality of fans are provided in order to force the printing medium to be forcedly dried over the entire range of the moving direction of the head device, resulting in an increase in the number of parts. In particular, in an inkjet printer for industrial use that performs printing on a large print medium, the number of fans tends to increase, which may increase the cost.

  The present invention has been made in view of such a problem, and an inkjet printer capable of preventing a decrease in printing performance and reducing costs in an inkjet printer capable of forcibly drying ink ejected onto a print medium. An object is to provide a printer.

In order to achieve the above object, an ink jet printer according to the present invention includes a support member (for example, stage 2 in the embodiment) that supports a part to be printed on a print medium conveyed in a predetermined direction, and a support member. Is disposed so as to be reciprocally movable in a scanning direction orthogonal to a predetermined direction, and has an ink ejecting hole for ejecting ink toward a printing medium supported by the supporting member so as to face the supporting member in the vertical direction. And a head device (for example, the printer head 4 in the embodiment) and one end side in the scanning direction with respect to the support member, and below the head device, and apply a negative pressure to the ink ejection holes to apply ink. and a suction to maintenance device, to eject ink from the ink ejection holes of the head unit to the printing medium supported by the supporting member while moving to one end from the other end side of the scanning direction In the ink jet printer configured to perform printing, a fan is attached to the outer portion of the head device on the other end side in the scanning direction so as to blow obliquely downward toward the other end side in the scanning direction. And a housing member that accommodates the support member, the head device, and the maintenance device therein. The housing member is supported by the housing member and a first opening that is formed so as to communicate the inside and the outside of the housing member. A second opening is formed in a portion of the member that faces the other end in the scanning direction in the scanning direction so as to communicate the inside and the outside of the housing member.

  According to the ink jet printer of the present invention, the fan is attached to the outer portion of the head device disposed above the support member that supports the portion to be printed on the print medium, and the fan moves the head device. Operates when printing is in progress. For this reason, forced drying is performed immediately after the ink is ejected onto the print medium, and the ink can be evaporated at an early stage so that the printed matter can be brought into a finished state at an early stage. In addition, since the periphery of the head device is ventilated, the ink ejection holes are not clogged due to condensation, and deterioration in printing performance is prevented. In addition, since the fan is moved together with the head device, if one fan is provided, the portion to be printed on the print medium can be forcedly dried over the entire range in the direction orthogonal to the transport direction. As a result, the number of fans can be reduced and the cost can be reduced.

  When a maintenance device for sucking ink is provided on one end side in the moving direction of the head device, the fan is similarly attached to one end side in the moving direction of the head device on the outer side of the head device. There is a possibility that ink attached to the maintenance device is blown off by the air blown from the fan. As described above, such a problem does not occur by providing the fan on the opposite side of the maintenance device.

  In addition, when a support member and a housing member that accommodates the head device are provided and the atmosphere around the head device is likely to be saturated with such components, an intake port and an exhaust port that communicate the inside and outside of the housing member are formed. By doing so, the air taken in from the outside can be blown from the fan, and the air containing the liquid component of the ink blown from the fan and evaporated can be discharged to the outside. As a result, the risk of condensation in the head device due to ventilation around the head device is reduced.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. As schematically shown in FIGS. 1 to 3, the inkjet printer 1 of the present configuration example is an industrial-use printing apparatus that performs printing on a large-sized sheet-like print medium 10 such as a roll paper. The stage 2 that supports the portion of the print medium 10 to be printed, the transport device 3 that transports the print medium 10 in a predetermined transport direction, and the reciprocation in the direction perpendicular to the transport direction of the print medium 10 above the stage 2 A printer head 4 movably provided is housed in a housing 9. In the following description, the illustrated arrow F is forward, arrow L is left, and arrow U is upward. The front-rear direction corresponds to the conveyance direction of the print medium 10 and the left-right direction corresponds to the movement direction of the printer head 4. doing.

  The stage 2 has a rectangular horizontal support surface 21, and a portion to be printed on the print medium 10 can be placed on and supported on the support surface 21. At this time, the printing medium 10 is sucked under a negative pressure on the support surface 21 through a large number of small holes 22 opened in the support surface 21.

  The transport device 3 includes a main roller 30 disposed on the supply direction supply side (rear) with respect to the stage 2 and a discharge roller 35 disposed on the discharge direction discharge side (front) with respect to the stage 2. It is configured. The main roller 30 and the paper discharge roller 35 are respectively configured to have feed rollers 31 and 36 and press rollers 32 and 37 that are rotatably provided around a rotation shaft extending in the left and right direction and sandwich the print medium 10 up and down. The The feed rollers 31 and 36 are disposed below the presser rollers 32 and 37 and are driven to rotate in forward and reverse directions by an electric actuator such as a servo motor. As shown in FIG. 1, the pressing rollers 32 and 37 can hold the print medium 10 interposed between the feeding rollers 31 and 36 by applying a pressing force to the outer peripheral surfaces of the feeding rollers 31 and 36 from above. It is movable up and down between the transport position and a retreat position that is spaced upward from the feed rollers 31 and 36 (not shown). When the feed rollers 31 and 36 are rotationally driven in a state where the print medium 10 is sandwiched, the press rollers 32 and 37 are driven and the print medium 10 is conveyed back and forth according to the rotation direction of the feed rollers 31 and 36. .

  The printer head 4 has a head bracket 41 attached to a rail-shaped guide member 46 extending left and right above the support surface 21 of the stage 2 and a plurality of heads 42 held side by side by the head bracket 41. Configured. The head bracket 41 is formed in a substantially rectangular box shape and holds the head 42 between the left and right side surfaces. The head bracket 41 is left and right along the guide member 46 while holding the head 42 by the electric actuator. It is reciprocated. Each head 42 has an ink flow path through which ink is supplied from an ink supply unit (not shown), and the ink connected to the ink flow path on the lower surface facing the support surface 21 of the stage 2 as shown in FIG. The ejection holes 43 are opened side by side in the front, rear, left, and right, so that the ink in the ink flow path is ejected downward from the ink ejection holes 43 when the pressure in the ink flow path is changed by the operation of the piezo element or the like. It is configured.

  The housing 9 is configured by detachably attaching an upper cover portion 92 to a lower base portion 91. Further, a discharge port 94 that allows the inside and the outside to communicate with each other is formed on the front end surface of the housing 9 integrated by assembling the cover portion 92 with the base portion 91. A holding mechanism 16 that holds the rolled print medium 10 is disposed inside the housing 9 below the main roller 30. The print medium 10 is disposed outside the housing 9 and in front of the discharge port 94. A winding mechanism 17 for winding the printed portion is provided.

  Before the ink jet printer 1 performs a printing operation, a setting operation for the print medium 10 is performed. By this setting operation, the end portion of the print medium 10 held by the holding mechanism 16 is pulled out and taken up by the take-up mechanism 17, and the print medium 10 is fed to the main side. The roller 31 is placed on each of the outer peripheral surface of the roller 31, the support surface 21 of the stage 2, and the outer peripheral surface of the feed roller 36 on the paper discharge side. Thereafter, the main presser roller 32 in the retracted position is moved to the transport position shown in FIG. 1, and the print medium 10 is sandwiched up and down by the main roller 30.

Then, ink is ejected from the ink ejection hole 43 to the portion to be printed on the printing medium 10 supported by the support surface 21 while the printer head 4 is reciprocated left and right once. In this configuration example, the following description is given assuming that the printing form is unidirectional printing, and ink is ejected only while moving to the left . By operating the transport device 3 to transport the print medium 10 forward, the portion where ink is ejected next is transported from below to the lower part of the printer head 4, and the portion where ink is ejected is transported forward. Thereafter, the reciprocating operation and the ink ejecting operation of the printer head 4 and the transporting operation of the printing medium 10 are repeated in this way, so that the printing on the printing medium 10 is performed and the ink of the printing medium 10 is ejected. Is discharged from the discharge port 94 to the outside of the housing 9. The printing medium 10 is supported on the stage 2 without being lifted from the support surface 21 by negative pressure suction, and the interval between the ink ejection holes 43 is always properly maintained when ink is ejected, and the printing performance is maintained. Is not compromised. Such operation control of the conveying device 3 and the printer head 4 is performed by a controller (not shown).

  Further, inside the housing 9, a cutter 5 is arranged between the stage 2 and the paper discharge roller 35 in the front-rear direction, and after the predetermined printing operation is performed, the print medium 10 is cut and divided into the front and rear, A heater 6 for heating the print medium 10 is provided. The cutter 5 is configured such that a cutting blade 52 is held by a holding member 51 configured to be movable up and down and left and right, and the holding member 51 is moved downward to apply the cutting edge of the cutting blade 52 to the printing medium 10. The print medium 10 is cut by moving the holding member 51 in the left and right direction in the state where the print medium 10 is in the closed state. The heater 6 includes a flat panel 60 having a placement surface 61 on which the print medium 10 conveyed from the stage 2 is placed, and a portion of the print medium 10 on which the ink is ejected is on the placement surface 61. The colorant can be fixed by evaporating the liquid component of the ink at an early stage. For this reason, the ink is dried when the print medium 10 is taken up by the take-up mechanism 17, and the ink does not adhere to the back surface of the print medium 10 when taken up by the take-up mechanism 17. In addition, a plurality of rollers 62 that press the print medium 10 against the placement surface 61 are provided above the placement surface 61, so that the printing medium 10 does not float from the placement surface 61, and the drying of the ink is uniform. Can be done.

  In the housing 9, a maintenance device 7 is provided on the left side of the stage 2 to maintain a state where ink is normally ejected from the ink ejection holes 43. A guide member 46 that guides the reciprocation of the head bracket 41 extends above the maintenance device 7 so that the printer head 4 can be moved above the maintenance device 7. The maintenance device 7 is configured to have a plurality of rubber caps 71 arranged side by side on the left and right (the alignment direction of the heads 42) on a base 7a provided so as to be movable up and down.

  In this inkjet printer 1, after the completion of a predetermined printing operation, the printer head 4 is moved above the maintenance device 7 and the base 7a is moved upward, so that the lower surface of each head 42 has a rubber cap 71. It is sealed with. As a result, the ink ejection holes 43 of each head 42 are positioned in a space sealed by the rubber cap 71, and it is possible to prevent the ink facing downward from the ink ejection holes 43 from drying. At the time of activation, the space sealed by the rubber cap 71 is set to a negative pressure, and the ink supplied into the ink flow path is sucked through the ink ejection holes 43. As a result, the ink that has been dried is removed and the ink flow path is filled with the ink newly supplied from the ink supply device, so that the ink is normally ejected from the ink ejection holes 43. After the ink is sucked, the base 7a is moved downward to start the printing operation. During the printing operation, a part of the sucked ink remains and adheres to the rubber cap 71.

  Here, during the printing operation, the peripheral area of the printer head 4 is closed by attaching the cover portion 92. For this reason, the printer head 4 cannot be easily accessed from the outside, and safety is ensured during the printing operation. On the other hand, depending on the ink used, the atmosphere in the closed peripheral region is a highly volatile component. May be saturated. By being saturated in this way, condensation may occur on the lower surface of the head 42 and the ink ejection holes 43 may be clogged, and ink may not be ejected normally.

  In this configuration example, a fan 80 is attached to the printer head 4 as shown in FIGS. The fan 80 is a small axial fan having a maximum static pressure of about 40 to 70 Pa, and is fixed to the printer head 4 via a fan bracket 47 fastened to the right side surface of the head bracket 41 of the printer head 4. .

  When fixed to the printer head 4, the fan 80 is provided such that the rotation axis is tilted up and down with respect to the horizontal direction, which is the moving direction of the head bracket 41, and the suction side is arranged on the upper left side in the rotation axis direction. The discharge side is arranged on the lower right side in the rotation axis direction. The housing 9 is formed with an exhaust port 95 in which a large number of circular holes are arranged on the right end surface of the cover portion 92.

  The fan 80 is activated when a printing operation is being performed. By the operation of the fan 80, the air taken in from the outside through the discharge port 94 for discharging the print medium 10 is sucked into the inside of the housing 9 as indicated by broken line arrows in FIGS. 2 and 3. An airflow that is led to the side is formed, and air from the discharge side of the fan 80 flows toward the right side in the peripheral area of the printer head 4 to form an airflow that is discharged to the outside from the exhaust port 95. Thus, the discharge port 94 for discharging the print medium 10 also functions as an intake port for taking air into the fan 80 from the outside to the inside. In addition, the heater 6 is disposed between the discharge port 94 and the fan 80, and the air around the heater 6 that has become high temperature due to radiant heat from the panel 60 is taken into the suction side of the fan 80. For this reason, it becomes possible to blow warm air from the discharge side of the fan 80.

As described above, the printing form of the inkjet printer 1 is a one-way printing form in which ink is ejected when the printer head 4 moves to the left. For this reason, when the printer head 4 is moved leftward, the air blown from the discharge side can be blown onto the portion to be printed of the print medium 10 onto which ink has been ejected during the previous leftward movement. While the printer head 4 is waiting on the upper left side of the stage 2 and the print medium 10 is conveyed by the conveying device 3, the air blown from the discharge side passes the peripheral area of the printer head 4 to the right exhaust port 95. It flows toward. Further, when the printer head 4 moves to the right, the fan 80 is gradually brought closer to the exhaust port 95. For this reason, exhaust of air in the peripheral area of the printer head 4 is urged.

  Thus, since the fan 80 is attached to the side surface of the printer head 4, the air from the fan 80 can be blown immediately after the ink is ejected onto the print medium 10. For this reason, it is possible to shorten the time until the ink is forcibly dried at an early stage and finished as a printed matter. At the same time, since the peripheral area of the printer head 4 is ventilated by the air taken from the outside of the housing 9, the atmosphere in the peripheral area is not saturated with the ink components, and the possibility of condensation on the lower surface of the head 42 is reduced. The For this reason, clogging of the ink ejection holes 43 is prevented, and the printing performance can be maintained.

  In addition, since the fan 80 is moved together with the printer head 4, with this movement, the entire area in the direction perpendicular to the conveyance direction of the print medium 10 with a single fan is applied to the portion to be printed of the print medium 10. Forced drying can be performed across. Therefore, the number of fans can be reduced and the cost can be reduced compared to the conventional case where the fans are fixed. Note that, in the inkjet printer 1 for industrial use in which the movement range of the printer head 4 is set large in order to perform printing on the large print medium 10 as in this configuration example, there is one fan. The effect of cost reduction is increased. Furthermore, in the conventional configuration in which a plurality of fans are provided near the print medium discharge port as in the prior art, the end of the print medium needs to be discharged from the discharge port in the setting operation of the print medium before printing. In some cases, the fan may get in the way and the setting work may become complicated. As in the present configuration example, with the structure in which the fan 80 is attached to the side surface of the printer head 4, the end of the print medium 10 is pulled out and placed on the stage 2, and is discharged from the discharge port 94 to be taken up. Therefore, the fan 80 does not get in the way and the setting operation of the print medium 10 can be performed easily.

  In this configuration example, the peripheral area of the printer head 4 is closed for the purpose of ensuring safety, but the cover portion 92 has an exhaust port 95 on the right end surface where the air from the fan 80 flows. The air flowing in the peripheral area of the printer head 4 is smoothly exhausted to the outside of the housing 9. In addition, a fan 80 is provided on the right side, which is one side of the moving direction of the printer head 4 that moves left and right, and the air blown from the fan 80 flows in the moving direction of the printer head 4. For this reason, when the printer head 4 is moved, the distance between the fan 80 and the exhaust port 95 is gradually shortened, and the exhaust of air in the peripheral area of the printer head 4 is promoted. This reduces the possibility that condensation will occur on the lower surface of the head 42.

  A maintenance device 7 that forcibly sucks ink from the ink ejection holes 43 is provided on the left side of the stage 2. Here, since the fan 80 is attached to the right side surface of the head bracket 41, the air from the fan 80 is not blown to the maintenance device 7 side. As described above, when the fan 80 is attached to the side surface in the moving direction of the printer head 4 with respect to the printer head 4, the fan 80 is disposed on the side opposite to the side on which the maintenance device 7 is disposed. The remaining ink is not blown off by the air blowing operation of the fan 80.

  Further, a heater 6 that warms the print medium 10 and promotes ink evaporation is disposed between the fan 80 and a discharge port 94 that takes in air from outside and functions as an intake port. The fan 80 is a heater. 6 can be taken in and air can be blown onto the print medium 10. For this reason, the time until the effect of forced drying of the ink is enhanced and the printed product is completed is shortened, and the ink can be more reliably dried at the stage of being wound by the winding mechanism 17. . In addition, the outside air is taken into the inside by using the exhaust port 94 in front of the fan 80 as described above, and the maintenance device 7 is turned on while the air from the outside is guided to the suction side of the fan 80. Avoiding this, air from outside is guided to the suction side of the fan 80. In this way, the ink adhering to the maintenance device 7 side is not blown off even by the airflow toward the suction side.

  The embodiments of the ink jet printer according to the present invention have been described so far, but the scope of the present invention is not limited to the above-described configuration. For example, the printing form is not limited to unidirectional printing, and the same effects as in the above configuration example can be obtained even in bidirectional printing. In the above configuration example, the fan 80 is always operated when the printing operation is performed. However, the fan 80 may be driven intermittently in order to reduce power consumption. Good.

It is a schematic diagram shown in the left sectional view of the ink jet printer according to the present invention. It is a schematic diagram shown by the plane cross section view of the said inkjet printer. It is a schematic diagram which shows a stage and a printer head by the front view in the said inkjet printer. It is a bottom view of the head provided in the printer head.

Explanation of symbols

1 Inkjet printer 2 Stage (support member)
4 Printer head (head device)
7 Maintenance device 9 Housing 10 Print medium 41 Head bracket 42 Head 43 Ink ejection hole 47 Fan bracket 80 Fan 94 Discharge port (intake port)
95 Exhaust port

Claims (1)

A support member that supports a portion to be printed on a print medium conveyed in a predetermined direction;
Above the support member is disposed so as to be able to reciprocate in a scanning direction orthogonal to the predetermined direction, and ejects ink toward a print medium supported by the support member so as to face the support member in the vertical direction. A head device having ink ejection holes;
A maintenance device that is disposed on one end side in the scanning direction with respect to the support member and below the head device and sucks ink by applying a negative pressure to the ink ejection holes;
An ink jet printer configured to perform printing by ejecting ink from the ink ejection holes onto a print medium supported by the support member while moving the head device from the other end side to the one end side in the scanning direction. In
A fan is attached to the outer portion of the head device on the other end side in the scanning direction so as to blow air obliquely downward toward the other end side in the scanning direction,
A housing member that houses the support member, the head device, and the maintenance device;
The housing member is
A first opening formed so as to communicate between the inside and the outside of the housing member;
A second opening formed so that the housing member communicates with the inside and the outside of the housing member at a portion of the support member facing the other end in the scanning direction in the scanning direction. An ink jet printer comprising:

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