JP6241291B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus.

  As a technique related to paper conveyance of a printer, for example, the technique disclosed in Patent Document 1 has already been proposed. In Patent Document 1, an intermediate roller pair is arranged between a paper feed roller that feeds a cut sheet from a hopper and a platen, and when the cut sheet is fed, the platen is rotated in the reverse direction and the intermediate roller pair is rotated forward. Therefore, when forming the bending of the cut sheet between the platen and the intermediate roller pair, the gear transmission mechanism to the intermediate roller pair engages with the intermediate roller pair so that the intermediate roller pair rotates positively when the platen rotates normally. In addition, a rocking gear that is brought into a non-engagement state when the platen is reversely rotated is interposed, and a transmission gear with a one-way clutch is provided that rotates idly when the platen rotates forward and operates when the platen rotates reversely.

Japanese Patent Laid-Open No. 04-70368 (Japanese Patent Application No. 02-173961)

  An object of the present invention is to enable protection of a recording head in conjunction with a continuous recording medium conveyance operation.

The invention described in claim 1 includes an inkjet recording head that records an image on a continuous recording medium;
A protective member to which a displacement force for displacing the inkjet recording head from a protective position for protecting the ink jet recording head to a retracted position;
Transporting means for transporting the recording medium in the forward direction so as to pass through the ink jet recording head, and transporting the recording medium back in the direction opposite to that at the time of recording at the end of the recording operation;
When the transport unit transports the recording medium in a direction opposite to that during recording, a driving force is transmitted from the transport unit to move the protection member from the retracted position to the protection position, and the transport unit moves the recording medium. When the ink is transported in the forward direction, the ink jet recording apparatus includes a moving unit that releases the driving force from the transport unit and moves the protection member from the protection position to the retracted position by the displacement force.

  According to a second aspect of the present invention, the moving means has one-way transmission means for transmitting the driving force from the transport means only in one direction, and is driven to the protection member via the one-way transmission means. 2. The ink jet recording apparatus according to claim 1, wherein force is transmitted.

The invention described in claim 3, direction acting displacement force to the protective member, according to claim 2, characterized in that said one-way transmission means is set in the direction opposite to the direction for transmitting the driving force The inkjet recording apparatus according to the above.

  The invention described in claim 4 is characterized in that a displacement force for displacing the protection member from the protection position toward the retracted position is applied by an elastic force of an elastic member. The inkjet recording apparatus according to any one of the above.

  According to a fifth aspect of the present invention, in the ink jet recording apparatus according to the fourth aspect, the elastic force of the elastic member is set to be smaller than a holding force for holding the conveying unit in a stopped state. It is.

  According to the first aspect of the present invention, it is possible to protect the recording head in conjunction with the continuous recording medium conveying operation, as compared with the case where the configuration of the invention is not provided.

  According to the second aspect of the present invention, it is possible to protect the recording head in conjunction with a continuous recording medium conveying operation with a simple configuration as compared with the case where the configuration of the invention is not provided.

  According to the third aspect of the present invention, it is possible to displace the protective member from the protective position to the retracted position by the displacement force when the conveying means is driven as compared with the case where the configuration of the invention is not provided.

  According to the invention described in claim 4, it is possible to displace the protection member from the protection position to the retracted position with a simple configuration as compared with the case where the configuration of the invention is not provided.

  According to the fifth aspect of the present invention, the protective member can be held in the protective position when the conveying means is stopped as compared with the case where the configuration of the invention is not provided.

It is a block diagram which shows the outline | summary of the inkjet recording device which concerns on Embodiment 1 of this invention. It is a block diagram which shows the principal part of an inkjet recording device. It is a plane block diagram which shows the principal part of an inkjet recording device. It is a graph which shows the speed change of the continuous paper of an inkjet recording device. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 1 of this invention. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 1 of this invention. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 1 of this invention. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 1 of this invention. 6 is a graph showing the continuous paper transport speed and the paper guide operation of the ink jet recording apparatus according to Embodiment 1 of the present invention. It is a block diagram which shows the modification of the inkjet recording device which concerns on Embodiment 1 of this invention. It is a block diagram which shows the principal part of the inkjet recording device which concerns on Embodiment 2 of this invention. It is a plane block diagram which shows the principal part of an inkjet recording device. It is a graph which shows the speed change of the continuous paper of an inkjet recording device, and operation | movement of a shutter member. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 2 of this invention. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 2 of this invention. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 2 of this invention. It is a block diagram which shows operation | movement of the inkjet recording device which concerns on Embodiment 2 of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes for carrying out the present invention (simply referred to as “embodiments”) will be described with reference to the accompanying drawings.

  1 and 2 show an ink jet recording apparatus according to Embodiment 1. FIG. FIG. 1 shows an outline of the whole of the ink jet recording apparatus, and FIG. 2 shows an enlarged main part (recording section, paper feeding section, etc.) in the ink jet recording apparatus.

<Overall configuration of inkjet recording apparatus>
The ink jet recording apparatus 1 according to the first embodiment is configured as a continuous form printer that records images on continuous form paper having a feed hole for pin feed, for example. The ink jet recording apparatus 1 includes an ink jet recording head 10 as an example of an ink jet recording unit that forms an image with ink of a desired color, and a continuous continuous recording medium to be supplied to a recording position of the ink jet recording head 10. A paper feeding device 20 as an example of a conveying unit that accommodates and conveys the book paper 5 and a paper discharge device as an example of a conveying means that conveys and accommodates the continuous paper 5 on which an image is recorded by the inkjet recording head 10. 30. The recording medium is not limited to the continuous paper having pin feed holes, and continuous paper having no pin feed holes may be used.

  The ink jet recording apparatus 1 includes a housing 1a, and the housing 1a is formed of a support structure member, an exterior cover, an internal frame, and the like. Moreover, the continuous line in a figure shows the continuous paper 5 conveyed along a conveyance path | route inside the housing | casing 1a.

  The ink jet recording head 10 is arranged in a fixed state so as to be positioned at a required position in the internal space of the housing 1a. The inkjet recording head 10 forms a monochrome image on the continuous paper 5 by ejecting ink droplets from a nozzle (not shown) downward in the illustrated example based on an image signal input from an external device (not shown). To do. In the illustrated example, only one inkjet recording head 10 is illustrated, but a plurality of inkjet recording heads corresponding to each color such as yellow (Y), magenta (M), cyan (C), black (K), and the like. Of course, it may be configured to record a full-color image.

  Further, as shown in FIG. 3, the inkjet recording head 10 has a length corresponding to the width of the continuous paper 5 and can print an image over the entire width of the continuous paper 5 by one printing operation. It is configured to be possible. The ink jet recording head 10 is not necessarily limited to a length corresponding to the width of the continuous paper 5, and is formed shorter than the width of the continuous paper 5. The image may be printed by moving it along the line.

  The paper feeding device 20 includes a single (or plural) paper container (paper hopper) 21 that accommodates the long continuous paper 5 in a folded state to a required size (for example, A4 size or A3 size), A feeding device 22 composed of a tractor feeding mechanism for feeding the folded continuous paper 5 from the paper container 21 and the upstream side of the inkjet recording head 10, and a forward rotation direction A and a reverse rotation direction by a drive source (not shown). It is mainly comprised by the conveyance roll 23 as an example of the conveyance means rotationally driven along B. The paper container 21 is attached, for example, so that it can be pulled out to the front side (side surface on which the user faces during operation) of the housing 1a. The continuous paper 5 may be roll paper wound in a roll shape other than the one folded into a desired size.

  The feeding device 22 including a tractor feeding mechanism and the like includes belt-like conveying members 221 disposed at both ends along a direction intersecting with the conveying direction of the continuous paper 5 (hereinafter referred to as “width direction”). ing. The belt-shaped conveying member 221 is stretched between a pair of rolls 222 and 223 composed of a driving roll and a driven roll driven by a driving source (not shown), and the surface thereof extends along the width direction of the continuous paper 5. The projections 224 are provided at intervals equal to the intervals between the feed holes for pin feed formed at both ends. Then, the feeding device 22 moves the continuous paper 5 along the normal rotation direction A and the reverse rotation direction B in a state where the convex portion 224 of the belt-shaped transport member 221 is inserted into the pin feed feed hole of the continuous paper 5. Transport.

  Further, the paper discharge device 30 holds and conveys the continuous paper 5 on which the image is recorded by the inkjet recording head 10 and conveys the continuous paper 5 and the continuous paper 5 conveyed by the conveyance roll pair 31. The paper is mainly composed of a pair of discharge rolls 32 that hold and discharge in a state where the paper is sandwiched, and a single (or plural) paper discharge body (paper stacker) 33 that accommodates the continuous paper 5 in a folded state. The paper discharge body 33 is attached so that it can be pulled out, for example, to the front surface (side surface facing the user during operation) of the housing 1a.

  The transport roll pair 31 includes a drive roll 31a that is rotationally driven by a drive source (not shown), and a driven roll (pinch roll) 31b that is driven to rotate by contacting the drive roll (drive roll) 31a via the continuous paper 5. It is configured. Similarly, the discharge roll pair 32 is also driven by a drive roll (drive roll) 32a that is rotationally driven by a drive source (not shown), and a driven roll (pinch) that rotates in contact with the drive roll 32a via the continuous paper 5. Roll) 32b.

  As shown in FIG. 1, the paper feeding device 20 and the paper discharge device 30 not only convey the continuous paper 5 along the normal rotation direction A, but also move the continuous paper 5 in the reverse direction B at a required timing. It is configured to be transportable over a required distance along.

  More specifically, the continuous paper 5 is in a state where the top of the page of the continuous paper 5 is stopped at the reference position S before the start of the image recording (printing) operation or when waiting for printing, as shown in FIG. . Then, the paper feeding device 20 and the paper discharge device 30 start transporting the continuous paper 5 based on the start signal of the printing operation, and after the transport speed of the continuous paper 5 reaches a required speed, the inkjet recording head 10 starts printing on the continuous paper 5. The paper feeding device 20 and the discharge device 30 stop the conveyance of the continuous paper 5 after the printing operation by the ink jet recording head 10 is completed. Further, after stopping the conveyance of the continuous paper 5, the paper feeding device 20 and the paper discharge device 30 are driven in the reverse direction B to convey the continuous paper 5 by a predetermined distance in the reverse direction to the recording time. (Retracts) and stops, waiting for printing.

  In FIG. 1, reference numeral S indicates a reference position when the continuous paper 5 is stopped. The reference position S is set at a position away from the recording position of the inkjet recording head 10 by a predetermined distance on the upstream side in the conveyance direction of the continuous paper 5.

  Unlike the case of recording an image on a cut sheet, the inkjet recording apparatus 1 records an image on a continuous paper 5 that is a continuous sheet. After the printing on the continuous paper 5 by the inkjet recording head 10 is stopped, when the conveyance of the continuous paper 5 by the paper feeding device 20 and the paper discharge device 30 is stopped, the printing is stopped as shown in FIG. Then, the continuous paper 5 is conveyed along the normal rotation direction A by a required distance until the continuous paper 5 is actually stopped. Therefore, the continuous paper 5 is reversed by the paper feeding device 20 and the paper discharge device 30 at the end of the printing operation so that printing can be started from the top of the next page of the continuous paper 5 at the start of the next printing. An operation of conveying (retracting) a predetermined distance along the direction and stopping at the reference position S is always performed.

  FIG. 2 is a block diagram showing a main part of the ink jet recording apparatus according to the first embodiment.

  As shown in FIGS. 2 and 3, the transport roll 23 includes a drive gear 24 as an example of a moving unit at one end in the axial direction thereof. The drive gear 24 of the transport roll 23 is meshed with a driven gear 26, which is also an example of a moving means that incorporates a one-way clutch mechanism 25. In the present embodiment, the driven gear 26 has an outer diameter larger than that of the drive gear 24 and a larger number of teeth than that of the drive gear 24. The driven gear 26 includes an outer ring member (outer race) 261 and an inner ring member (inner race) 262 in which teeth constituting the gear are formed on the outer periphery of the driven gear 26, and the outer ring member 261 and the inner ring member 262 are connected to each other. A one-way clutch mechanism 25 as an example of a one-way transmission means is built in between. In the one-way clutch mechanism 25, when the outer ring member 261 rotates in one direction (counterclockwise direction in the illustrated example) with respect to the inner ring member 262, the clutch is engaged and torque is transmitted to the inner ring member 262. When the outer ring member 261 rotates in the reverse direction (clockwise direction in the illustrated example), the clutch is disengaged and torque is not transmitted to the inner ring member 262. The driven gear 26 has an inner ring member 262 rotatably attached to the inner frame 43 of the apparatus housing 1a.

  Further, as shown in FIG. 2, a paper guide 40 as an example of a protection member that protects the inkjet recording head 10 from collision of the continuous paper 5 is provided on the ink jet recording head 10 side of the driven gear 26. . As shown in FIGS. 2 and 3, the paper guide 40 is formed in a flat plate shape having a length substantially equal to that of the ink jet recording head 10, and the front end portion 40a located on the ink jet recording head 10 side is upward. It is formed in a substantially L-shaped side surface that is bent toward the side. Further, the paper guide 40 has a rotation shaft 41 provided in a fixed state at the base end portion 40 b, and the rotation shaft 41 is an internal frame 42, 43 constituting the housing 1 a of the inkjet recording apparatus 1. It is rotatably supported between them.

  Further, the rotational driving force of the inner ring member 262 is transmitted to the rotation shaft 41 of the paper guide 40 via the inner ring member 262 of the driven gear 26 and a link member 44 as an example of a connecting member formed in a rod shape or a flat plate shape. The inner ring member 262 is coupled so as to rotate in the same direction.

  Further, a lower end portion of a tension spring 46 as an example of an elastic member stretched between the intermediate portion 40 c of the paper guide 40 and the support portion 45 provided in the housing 1 a of the inkjet recording apparatus 1 is connected. ing. An elastic force (displacement force) is always applied to the paper guide 40 so as to be moved (displaced) upward by the tension spring 46. A first stop member 47 is provided above the paper guide 40 to stop the paper guide 40 when the paper guide 40 moves (rotates) upward about the rotation shaft 41. A position where the sheet guide 40 moves upward and comes into contact with the first stop member 47 and stops is a retracted position of the sheet guide 40.

  Further, below the paper guide 40, when the paper guide 40 is driven to rotate counterclockwise via the link member 44, the paper guide 40 comes into contact with the back surface of the paper guide 40 and stops moving downward. Two stop members 48 are provided. The position where the paper guide 40 is moved downward and stopped prevents the ink jet recording head 10 from being damaged by the continuous paper 5 by suppressing the paper guide 40 from moving upward on the continuous paper 5. The sheet guide 40 is protected.

  In this embodiment, the drive gear 24, the driven gear 26, and the link member 44 constitute moving means.

<Basic operation of inkjet recording apparatus>
The basic operation of the ink jet recording apparatus will be described below.

-When the paper is stopped (print standby)-
As shown in FIG. 4, the inkjet recording apparatus 1 is in a state in which the paper feeding device 20 and the paper ejection device 30 are stopped before the start of the image recording (printing) operation or when waiting for the printing operation, and the continuous paper 5 The moving speed of is zero.

  In the state where the paper feeding device 20 is stopped, as shown in FIG. 5, the paper guide 40 has moved to the protection position located below. At this time, the rotation shaft 41 of the paper guide 40 is connected to the inner ring member 262 of the driven gear 26 via the link member 44. Further, the driven gear 26 is meshed with the drive gear 24 of the transport roll 23, and the transport roll 23 holds the stopped state. Therefore, the paper guide 40 holds the protection position even when the elastic force by the tension spring 46 is acting.

  More specifically, the transport roll 23 of the paper feeder 20 is operatively connected to a drive source via a driving force transmission mechanism including a plurality of gears (not shown) that rotationally drive the transport roll 23. In this state, the vehicle is held in a stopped state with a required holding force determined by meshing of gears constituting the driving force transmission term.

  An elastic force is applied to the paper guide 40 so as to move upward by the tension spring 46, but the stop state holding force of the transport roll 23 is set larger than the elastic force of the tension spring 46, so The guide 40 can maintain the state of moving to the protection position. At that time, a rotational force in the clockwise direction is applied to the rotation shaft 41 of the paper guide 40 by the elastic force of the tension spring 46, but the driven gear 26 connected to the rotation shaft 41 via the link member 44. Includes a one-way clutch mechanism 25. The one-way clutch mechanism 25 is configured such that when the outer ring member 261 rotates in one direction (counterclockwise direction in the illustrated example) with respect to the inner ring member 262, the clutch is engaged and torque is transmitted to the inner ring member 262. The inner ring member 262 maintains the stopped state by the holding force that holds the stopped state of the outer ring member 261.

−During printing operation−
As shown in FIG. 4, in the inkjet recording apparatus 1, at the start of the printing operation, the paper feeding device 20 and the paper discharging device 30 are activated, and the continuous paper 5 is rotated forward by the paper feeding device 20 and the paper discharging device 30. The conveyance in the direction A is started. At this time, the transport roll 23 of the paper feeding device 20 is rotationally driven in the counterclockwise direction in the figure as shown in FIG. Therefore, the outer ring member 261 of the driven gear 26 meshed with the drive gear 24 provided at the end of the transport roll 23 is driven to rotate clockwise. The driven gear 26 incorporates a one-way clutch mechanism 25, and when the outer ring member 261 rotates in the clockwise direction with respect to the inner ring member 262, the clutch is released and torque is applied to the inner ring member 262. It is the composition which is not transmitted to.

  Conversely, when the inner ring member 262 rotates in the clockwise direction with respect to the outer ring member 261, the one-way clutch mechanism 25 engages the clutch and transmits torque to the outer ring member 261. However, during the printing operation, as described above, the outer ring member 261 of the driven gear 26 is driven to rotate in the clockwise direction, so that the inner ring member 262 also rotates in the clockwise direction as the outer ring member 261 rotates in the clockwise direction. It can rotate in the direction of rotation.

  Therefore, when the outer ring member 261 of the driven gear 26 is driven to rotate in the clockwise direction at the start of the printing operation, the inner ring member 262 can also rotate in the clockwise direction. As a result, as shown in FIG. 7, the sheet guide 40 starts moving to the upper retracted position by the elastic force of the tension spring 46, moves to the retracted position in contact with the first stop member 47, and stops. To do.

  As described above, at the start of the printing operation, the paper guide 40 is positioned at the protected position of the inkjet recording head 10 as shown in FIGS. When the conveyance of the paper 5 is unstable, the crease 5a of the continuous paper 5 protrudes upward from the paper conveyance path and collides with the inkjet recording head 10, and the inkjet recording head 10 is damaged by the continuous paper 5. Is avoided.

  After the start of the printing operation, as shown in FIG. 7, the paper guide 40 moves (displaces) from the protection position to the retracted position by the elastic force of the tension spring 46, so that the paper guide 40 moves to the continuous paper 5. There will be no hindrance to transportation.

-At the end of printing-
As shown in FIG. 4, in the inkjet recording apparatus 1, when the printing operation is finished, the driving of the paper feeding device 20 and the paper discharging device 30 is stopped, and the continuous paper 5 is stopped. Thereafter, the paper feeding device 20 and the paper discharge device 30 are stopped after transporting the continuous paper 5 by a required distance in the reverse rotation direction B, which is the reverse direction to the normal rotation direction A, and wait for printing.

  At this time, the transport roll 23 of the paper feeder 20 stops after rotating by a required amount of rotation in the reverse direction B as shown in FIG. Therefore, the outer ring member 261 of the driven gear 26 meshed with the drive gear 24 provided at the end of the transport roll 23 is driven to rotate in a counterclockwise direction over a required rotation angle. The driven gear 26 has a built-in one-way clutch mechanism 25. When the outer ring member 261 rotates counterclockwise with respect to the inner ring member 262, the clutch engages with the inner ring member 262 to generate torque. It is configured to transmit to H.262.

  Therefore, when the outer ring member 261 of the driven gear 26 rotates counterclockwise, the one-way clutch mechanism 25 is engaged, and the inner ring member 262 rotates counterclockwise by an angle corresponding to the rotation angle of the outer ring member 261. The rotation of the inner ring member 262 is transmitted to the rotation shaft 41 of the paper guide 40 via the link member 44. The paper guide 40 rotates counterclockwise against the elastic force of the tension spring 46 by a required angle as the rotary shaft 41 rotates, and moves (displaces) to the protected position in contact with the second stop member 12. ) And stop.

  The rotation angle of the paper guide 40 in the counterclockwise direction is determined by the rotation amount of the transport roll 23 in the reverse direction B and the meshing ratio of the drive gear 24 and the driven gear 26. The rotation angle of the paper guide 40 is The angle at which the paper guide 40 is displaced from the retracted position to the protected position is set.

  However, since the paper guide 40 stops at the protection position in contact with the second stop member 48, as shown in FIG. 10, for the purpose of preventing an excessive force from acting on the paper guide 40, It is desirable to interpose a torque limiter 49 that limits the torque to a required value between the inner ring member 262 of the driven gear 26 and the link member 44.

−When resuming printing operation−
When the printing operation is resumed, as shown in FIG. 4, in the inkjet recording apparatus 1, the paper feeding device 20 and the paper discharging device 30 are activated and the paper feeding device 20 and the paper discharging device 30, as at the start of the printing operation. As a result, the continuous paper 5 is conveyed along the normal rotation direction A at a required conveyance speed. Then, the sheet guide 40 moves from the protection position to the retracted position as the transport roll 23 rotates.

  As described above, in the above embodiment, the conveyance state of the continuous paper 5 becomes unstable at the start of the printing operation, and the crease 5a of the continuous paper 5 is caused by the crease of the crease attached to the continuous paper 5 or the like. Can be prevented from coming off the transport path and colliding with the inkjet recording head 10 to damage the inkjet recording head 10.

  In addition, since the paper guide 20 moves to the retracted position after the printing operation is started, the paper guide 40 does not interfere with the recording operation of the inkjet recording head 10, and the printing operation by the inkjet recording head 10 is executed. Is done.

Embodiment 2
FIG. 11 shows an embodiment of the present invention. The same reference numerals are given to the same portions as those in the above-described embodiment. In Embodiment 2, the protective member is a recording of an ink jet recording head. Configured to protect the part from drying.

  That is, in the second embodiment, as illustrated in FIG. 11, a shutter as an example of a protective member that protects the recording unit 10 a of the inkjet recording head 10 is provided on the lower end surface 10 a that is the recording unit of the inkjet recording head 10. A member 50 is provided. The shutter member 50 is formed in a flat rectangular plate shape from metal, synthetic resin, or the like. Further, the shutter member 50 includes a slit-shaped opening 51 at a position corresponding to the recording unit 10 a of the inkjet recording head 10.

  At both ends along the width direction of the shutter member 50, as shown in FIG. 12, guide members 52 and 53 for guiding the shutter member 50 movably along the arrow direction are arranged. The shutter member 50 is connected to two tension springs 56, 57 having one end supported by support portions 54, 55 provided on the casing 1 a of the inkjet recording apparatus 1. An elastic force is applied so as to move to the normally opened open position (retracted position). Further, the shutter member 50 is provided with a flat plate-shaped regulating member 58 for stopping the shutter member 50 at the open position. The regulating member 58 of the shutter member 50 stops the shutter member 50 at the open position (retracted position) by abutting against a stop member 59 provided in the housing 1a of the inkjet recording apparatus 1.

  In addition, a drive gear 60 is attached to one end portion in the axial direction of the drive roll 31a of the conveyance roll pair 31 of the paper discharge device 30. The drive gear 60 is driven by a one-way clutch mechanism 61. The gear 62 is meshed. The driven gear 62 has its outer diameter and the number of teeth set to required values. The driven gear 62 includes an outer ring member (outer race) 621 and an inner ring member (inner race) 622 in which teeth constituting the gear are formed on the outer periphery of the driven gear 62, and the outer ring member 621 and the inner ring member 622 are connected to each other. A one-way clutch mechanism 61 as an example of a one-way transmission means is built in between. In the one-way clutch mechanism 61, when the outer ring member 621 rotates in one direction (counterclockwise direction in the illustrated example) with respect to the inner ring member 622, the clutch is engaged and torque is transmitted to the inner ring member 622. When the outer ring member 621 rotates in the reverse direction (clockwise in the illustrated example), the clutch is disengaged and torque is not transmitted to the inner ring member 622. The driven gear 62 has an inner ring member 622 attached rotatably to the internal frame 43 of the apparatus housing 1a.

  The inner ring member 622 of the driven gear 62 is connected to one end portion 63a of a driving wire 63 as an example of a driving force transmitting means on the outer periphery of the side surface. The other end 63 b of the drive wire 63 is connected to the downstream end of the shutter member 50 via a bar-shaped or roll-shaped relay member 64 disposed on the downstream side of the shutter member 50.

<Basic operation of inkjet recording apparatus>
The basic operation of the ink jet recording apparatus according to the second embodiment will be described below.

-When the paper is stopped (print standby)-
As shown in FIG. 13, the inkjet recording apparatus 1 is positioned at a closed position (protection position) where the shutter member 50 closes the recording unit 10 a of the inkjet recording head 10 before the start of the printing operation or when waiting for the printing operation. ing.

  That is, when the paper feeding device 20 is stopped, as shown in FIG. 14, the opening 51 of the shutter member 50 is displaced from the recording unit 10a of the inkjet recording head 10 to protect the recording unit 10a. Moved to a protected position. At this time, the shutter member 50 is connected to the inner ring member 622 of the driven gear 62 via the drive wire 63. Further, the driven gear 62 is meshed with the drive gear 60 of the drive roll 31a, and the drive roll 31a maintains a stopped state in the print standby state.

  More specifically, the drive roll 31a of the paper discharge device 30 is operatively connected to a drive source via a drive force transmission mechanism including a plurality of gears (not shown) that rotationally drive the drive roll 31a. In this state, the vehicle is held in a stopped state with a required holding force determined by meshing of gears constituting the driving force transmission term.

  At that time, the shutter member 50 is given an elastic force toward the right in the figure by the tension springs 56 and 57, but the stop state holding force of the drive roll 31 a is greater than the elastic force of the tension springs 56 and 57. Therefore, the shutter member 50 can hold the state moved to the protection position.

  As described above, when waiting for the printing operation, the shutter member 50 is positioned at the protective position where the recording unit 10a of the inkjet recording head 10 is closed, and the recording unit 10a of the inkjet recording head 10 is exposed to the air and dried. Is prevented.

-At the start of printing operation-
As shown in FIG. 11, in the inkjet recording apparatus 1, when the printing operation starts, the paper feeding device 20 and the paper discharging device 30 are activated, and the continuous paper 5 is required by the paper feeding device 20 and the paper discharging device 30. It is conveyed along the forward rotation direction A at the conveyance speed. At this time, the drive roll 31a of the paper discharge roll pair 31 is rotationally driven in the counterclockwise direction in the figure as shown in FIG. Therefore, the outer ring member 621 of the driven gear 62 meshed with the drive gear 60 provided at the end of the drive roll 31a is driven to rotate clockwise. The driven gear 62 incorporates a one-way clutch mechanism 61, and when the outer ring member 621 rotates in the clockwise direction with respect to the inner ring member 622, the clutch is disengaged and torque is applied to the inner ring member 622. It is the composition which is not transmitted to.

  Further, in the one-way clutch mechanism 61, when the inner ring member 622 rotates in the clockwise direction with respect to the outer ring member 621, the clutch is engaged and torque is transmitted to the outer ring member 621. However, during the printing operation, as described above, the outer ring member 621 of the driven gear 62 rotates in the clockwise direction, so that the inner ring member 622 also rotates in the clockwise direction as the outer ring member 621 rotates in the clockwise direction. Can be rotated.

  Therefore, when the outer ring member 621 of the driven gear 62 is driven to rotate in the clockwise direction at the start of the printing operation, the inner ring member 622 can also rotate in the clockwise direction. As a result, the shutter member 50 starts to move to the retracted position in the right direction in the figure by the elastic force of the tension springs 56 and 57, and the regulating member 58 provided on the shutter member 50 is a stop member on the apparatus housing 1a side. Stops in a state where it is abutted against 59.

  Thus, at the start of the printing operation, the shutter member 50 is moved to the retracted position where the recording unit 10a of the inkjet recording head 10 is opened, the recording unit 10a of the inkjet recording head 10 is opened, and the continuous paper 5 The printing operation can be performed.

-At the end of printing-
As shown in FIG. 11, in the inkjet recording apparatus 1, when the printing operation is completed, the driving of the paper feeding device 20 and the paper ejection device 30 is stopped, and the continuous paper 5 is stopped. Thereafter, the paper feeding device 20 and the paper discharge device 30 are stopped after transporting the continuous paper 5 by a required distance in the reverse rotation direction B, which is the reverse direction to the normal rotation direction A, and wait for printing.

  At this time, the drive roll 31a of the paper discharge device 30 stops after rotating by the required amount of rotation in the reverse rotation direction B as shown in FIG. Therefore, the outer ring member 621 of the driven gear 62 meshed with the drive gear 60 provided at the end of the drive roll 31a rotates following the required rotation angle in the counterclockwise direction. The driven gear 62 incorporates a one-way clutch mechanism 61, and when the outer ring member 621 rotates counterclockwise with respect to the inner ring member 622, the clutch engages and torque is applied to the inner ring member. 622 is transmitted to 622.

  Accordingly, when the outer ring member 621 of the driven gear 62 rotates counterclockwise, the one-way clutch mechanism 61 is engaged, and the inner ring member 622 rotates counterclockwise by an angle corresponding to the rotation angle of the outer ring member 621. The rotational force of the inner ring member 622 is transmitted to the shutter member 50 through the drive wire 63, and the shutter member 50 resists the elastic force of the tension springs 56 and 57 by a required distance as the drive wire 63 moves. Then, it moves to the left in the figure, stops after moving (displaced) to the closed position (protection position) where the recording portion 10a of the inkjet recording head 10 is closed.

  The moving distance of the shutter member 50 in the closing direction is determined by the rotation amount of the driving roll 31a in the reverse rotation direction B and the meshing ratio of the driving gear 60 and the driven gear 62. The moving distance of the shutter member 50 is The distance is set equal to the distance at which the shutter member 50 is displaced from the retracted position to the protected position.

  The shutter member 50 only needs to move from the retracted position to the protected position with the rotation of the drive roll 31a in the reverse rotation direction B, and the necessity of accurately defining the moving distance of the shutter member 50 is low. However, in order to prevent an excessive force from acting on the shutter member 50 when the shutter member 50 moves to the protection position, as shown in FIG. It is desirable to interpose the tension spring 70 or intervene between the inner ring member 622 of the driven gear 62 and the drive wire 63 with a torque limiter that limits the torque to a required value.

−When resuming printing operation−
In the ink jet recording apparatus 1, when the printing operation is resumed, as shown in FIG. 11, the paper feeding device 20 and the paper discharging device 30 are activated and the paper feeding device 20 and the paper discharging device 30, as at the start of the printing operation. As a result, the continuous paper 5 is conveyed along the normal rotation direction A at a required conveyance speed. The shutter member 50 moves from the protection position (closed position) to the retracted position (open position) with the rotation of the drive roll 31 a of the transport roll pair 31.

  As described above, in the above embodiment, at the start of the printing operation, the shutter member 50 that protects the recording unit 10a of the inkjet recording head 10 is driven in conjunction with the driving of the conveyance roll pair 31 of the paper discharge device 30. Therefore, it is possible to prevent the recording unit 10a of the inkjet recording head 10 from being exposed and dried when waiting for the printing operation, and the conveyance state of the continuous paper 5 becomes unstable at the start of the printing operation. The crease of the crease attached to the paper 5 causes the crease of the continuous paper to come off the conveyance path and collide with the recording part 10a of the ink jet recording head 10, and the recording part 10a of the ink jet recording head 10 is damaged. It can be avoided.

  Further, immediately after starting the printing operation, the shutter member 50 moves to the retracted position (open position), so that the shutter member 50 does not interfere with the recording operation of the inkjet recording head 10 and printing by the inkjet recording head 10 is performed. The operation can be executed.

  In the second embodiment, the case where a flat plate-like member is used as the shutter member has been described. However, as the shutter member, a sheet-like or film-like member may be used, and the sheet-like or film-like member may be used. The shutter member may be configured to move between the protection position and the retracted position in conjunction with the conveyance of the continuous paper 5.

DESCRIPTION OF SYMBOLS 1 ... Inkjet recording device 5 ... Continuous paper 10 ... Inkjet recording head 20 ... Paper feeding device 23 ... Conveying roll 24 ... Drive gear 25 ... One-way clutch mechanism 26 ... Driven gear 261 ... Outer ring member 262 ... Inner ring member 40 ... Paper guide 41 ... Rotating shaft 44 ... Link member 46 ... Tension spring

Claims (5)

An inkjet recording head for recording an image on a continuous recording medium;
A protective member to which a displacement force for displacing the inkjet recording head from a protective position for protecting the ink jet recording head to a retracted position;
Transporting means for transporting the recording medium in the forward direction so as to pass through the ink jet recording head, and transporting the recording medium back in the direction opposite to that at the time of recording at the end of the recording operation;
When the transport unit transports the recording medium in a direction opposite to that during recording, a driving force is transmitted from the transport unit to move the protection member from the retracted position to the protection position, and the transport unit moves the recording medium. An ink jet recording apparatus comprising: a moving unit that releases the driving force from the conveying unit and moves the protection member from the protection position to the retracted position by the displacement force when the sheet is conveyed in the forward direction.   The moving means includes one-way transmission means for transmitting a driving force from the conveying means in only one direction, and the driving force is transmitted to the protection member via the one-way transmission means. Item 10. The ink jet recording apparatus according to Item 1. 3. The ink jet recording apparatus according to claim 2 , wherein a direction in which a displacement force acts on the protection member is set in a direction opposite to a direction in which the one-way transmission unit transmits a driving force.   4. The ink jet recording apparatus according to claim 1, wherein a displacement force for displacing the protection member from the protection position toward the retracted position is applied by an elastic force of an elastic member.   The inkjet recording apparatus according to claim 4, wherein an elastic force of the elastic member is set to be smaller than a holding force for holding the conveying unit in a stopped state.

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