JP2007030206A - Image recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the size of an image recorder of ink jet recording system at a low cost by sharing one pretreatment liquid coating means among a plurality of transfer paths thereby eliminating the inconvenience of providing a coating means for each transfer path. <P>SOLUTION: Recording region of a sheet 13 from a first feed unit 10 or a sheet 55 from a second feed unit 60 is coated with pretreatment liquid containing a compound for making coloring agent in recording liquid (ink) insoluble by means of a coating roller 22 and then an image is recorded by means of a recording head 41. A plurality of transfer routes are selected in correspondence with the case when the pretreatment liquid is applied or not applied, and when recording is performed on one side or both sides of the sheets 13 and 55. A transfer path (common transfer section) 62b is shared by these transfer routes and the coating roller (coating means) 22 is provided only for the transfer path 62b. When the transfer route is selected, coating/recording operation can be carried out depending on the case by single print job. Since only one of a plurality of transfer routes requires the coating roller 22, size can be reduced at a low cost. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an inkjet recording type image recording apparatus in which a pretreatment liquid is applied in advance on a recording medium in order to improve image quality.

  Inkjet recording type image forming apparatuses such as copying machines, facsimile machines, and printers eject ink from a recording head and attach it to a recording medium (hereinafter referred to as a sheet) such as paper, cloth, non-woven cloth, and OHP paper. To record. The composition of the ink generally comprises a soluble color material, water as a main component, and a water-soluble high-boiling solvent such as glycol that is effective for preventing drying and clogging. However, in the case of such an ink, there are problems such as insufficient ink fixability and non-uniform ink density. Further, when a color image is to be obtained, a plurality of color inks are stacked one after another before being completely fixed on the sheet. For this reason, it is difficult to obtain a satisfactory image such as a color blurring or non-uniform mixing at the boundary between different color images.

  In order to solve these problems, the following methods and apparatuses that improve the quality of an image formed on a sheet by applying a pretreatment liquid to the recording surface of the sheet in advance before ink ejection are proposed. I came.

  For example, Patent Document 1 discloses an inkjet dyeing apparatus that impregnates a bleeding prevention liquid prior to recording. Patent Document 2 discloses a method for creating a printed image using an ink composition containing a chemical dye agent and a specific solution of a polyvalent metal salt solution as a pretreatment liquid. Patent Document 3 discloses an image recording method in which a pretreatment liquid is applied not only to a recording surface of a sheet but also to a non-recording surface on the back surface. Further, Patent Document 4 discloses an ink jet recording method in which a plurality of conveyance paths for conveying a sheet are selected to correspond to a case where the pretreatment liquid is applied and a case where the pretreatment liquid is not applied.

JP 61-75870 JP-A-5-202328 JP 2001-334642 A JP2003-11486A

  However, the method and apparatus of the above publication have the following problems.

  (1) Whether or not the pretreatment liquid is to be applied is selected, and once the application is performed on the surface to be recorded of the sheet and the recording is completed, one recording operation is completed. Therefore, when performing both-side recording after applying the pretreatment liquid on both surfaces to be recorded, the application and recording operation on the second surface is completed after the application and recording operation on the first surface is completed. There is a trouble of resetting the sheet. That is, when the coating is finished on the first surface and the recording is finished, the sheet is once discharged, and the discharged sheet is turned upside down on the second surface by a paper feed cassette or the like. Then, it is inefficient because the operation is repeated twice, such as restarting and starting application and recording operation on the second surface.

  (2) A plurality of dedicated transport paths corresponding to whether or not the pretreatment liquid is applied at the time of recording are provided. Therefore, the size of the image recording apparatus main body increases as the number of dedicated conveyance paths increases, resulting in a very high cost.

  (3) Further, when a plurality of feeding units including sheet feeding cassettes are provided, recording can be performed by applying a pretreatment liquid to a sheet fed from one feeding unit. The pretreatment liquid cannot be applied to the sheet fed from the feeding unit. Therefore, there is no selectivity or compatibility as in the case where a plurality of transport paths are dedicated, and they cannot be combined freely. Providing coating means for each conveyance path corresponding to a plurality of feeding units is also inconvenient because it increases the size and cost of the apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image recording apparatus capable of reducing the cost and size by eliminating the inconvenience of providing a coating means for each transport path by sharing one pretreatment liquid coating means in a plurality of transport paths. There is to do.

  In order to achieve the above object, the image recording apparatus of the present invention applies a pretreatment liquid containing a compound that insolubilizes the colorant in the recording liquid to the recording area of the sheet by the application means, and after application by the image recording means. In the image recording area, the coating unit is provided in a common conveyance section shared by at least two of a plurality of selectable and combinable conveyance routes for conveying the sheet toward the image recording unit. It is characterized by that.

  The image recording apparatus of the present invention has the following effects. There are a plurality of conveyance routes for conveying the sheet to the image recording means, and at least two of the conveyance routes share a common conveyance section. By providing the pretreatment liquid application means in the common conveyance section, the disadvantage of providing the application means for each conveyance route is eliminated, and a downsized apparatus can be realized at low cost. In addition, the recording operation can be performed with a single print job, corresponding to the case where the pretreatment liquid is applied or not applied, and the case where the recording is performed on one side or both sides of the sheet. is there.

  Preferred embodiments of the image recording apparatus of the present invention will be described below with reference to the drawings.

(First embodiment)
As shown in FIG. 1, the image recording apparatus of this embodiment includes a feeding unit (feeding unit) 10 that separates and feeds a plurality of sheets 13 stacked and stored one by one. In order to distinguish from a second feeding unit (second feeding unit) 60 provided in a second embodiment described later, the feeding unit 10 is hereinafter referred to as a first feeding unit (first feeding unit). Call. A recording head that includes a conveyance roller 31 and a discharge roller 33 that intermittently convey the sheet 13 fed from the first feeding unit 10 at regular intervals, and performs recording by reciprocating on the sheet 13. A recording unit (image recording means) 30 having 41 is provided. The recording unit 30 performs recording on the sheet 13 by reciprocating the recording head 41 in the sheet width direction (sub-scanning direction) while intermittently feeding the sheet 13 in the sheet conveyance direction (main scanning direction). The recording head 41 is carried by a carriage 42, and the carriage 42 slides back and forth on a slide shaft 43 and a slide rail 44 fixed to the chassis of the image recording apparatus main body 1.

  Further, between the first feeding unit 10 and the recording unit 30, there is an application unit (application unit) 20 that conveys the sheet 13 and applies the pretreatment liquid to the sheet 13. The coating unit 20 includes a feeding path 37 that transports the sheet 13 fed from the first feeding unit 10, and a rush path 26 that communicates with the feeding path 37 and extends toward the transport roller 31. Have Further, the reversing base 28 forms a horizontal conveyance path from the conveyance roller 31 at substantially the same level as the platen 35, and is connected to a pretreatment liquid coating mechanism which will be described next. A reversing path 24 formed in a U-turn shape from the reversing base 28 communicates with a side end portion of the feeding path 37. A reflective photosensor 38 is disposed on the upstream side of the conveying roller 31.

  If the sheet surface to be recorded after applying the pretreatment liquid is only one side (first side) or both sides (first side and second side), if the sheet side to be recorded without coating is one side or both sides, Accordingly, the first to third conveyance routes for conveying the sheet 13 to the recording unit 30 are selected.

  In the first conveyance route, the sheet 13 separated and fed from the first feeding unit 10 is sent directly to the recording head 41 through the feeding path 37 and the rushing path 26, and only one side is recorded without applying the pretreatment liquid. “Non-application / single-sided recording route”.

  In the second conveyance route, the sheet 13 is once sent from the first feeding unit 10 to the recording head 41, and the sheet 13 is reversely fed without recording at this stage. While applying the pretreatment liquid to the first surface of the reversely fed sheet 13 by the application roller (application mechanism) 22, it is reversed by the U-turn reversing path 24, and is sent again to the recording head 41 with the first surface facing upward. “Single-sided application / single-sided recording route”.

  On the other hand, the third transport route is a “double-sided application / double-sided recording route”. That is, the sheet 13 is once sent from the first feeding unit 10 to the recording head 41, and at this stage, the sheet 13 is reversely fed without recording. While applying the pretreatment liquid to the first surface of the reversely fed sheet 13 by the application roller (application mechanism) 22, it is reversed by the U-turn reversing path 24, and is sent again to the recording head 41 with the first surface facing upward. To do. After such one-side recording, the sheet 13 is not discharged, but the sheet 13 is reversely fed, the pretreatment liquid is applied to the second surface by the application roller 22, reversed by the U-turn reversing path 24, and the second surface is directed upward. And record on the second side. That is, it is a conveyance route for performing double-sided coating and double-sided recording. When this third transport route is considered as a combined route of the first and second transport routes, the U-turn inversion path 24 is a “common transport section” shared by the first transport route and the second transport route. Can be interpreted.

  2 and 3 show a coating mechanism in the coating unit 20 configured with the coating roller 22 and the pressure roller 23 as main parts.

  As shown in FIG. 2, it has the pan 52 of the container which stores a pretreatment liquid, and the absorber sticks 51 and 54 which consist of fibers are filled here. The absorber sticks 51 and 54 are urged together with the pan 52 in a direction to be pressed against the application roller 22 by a spring member (not shown). A storage bag 53 filled with the pretreatment liquid is disposed at a height position near the intermediate level of the pan 52. The liquid level of the pretreatment liquid is set to the height of the lower storage bag 53 in the direction of gravity with respect to the contact surface with the application roller 22. One absorber stick 51 region is filled with the pretreatment liquid. The area of the other absorbent stick 54 is impregnated with a pretreatment liquid between the compressed fibers by the capillary action of the fiber so that the pretreatment liquid can be supplied to a level up to the contact surface with the coating roller 22.

  Accordingly, the pretreatment liquid is transferred and attached to the application roller 22 so as to be transferred from the absorber sticks 51 and 54. The attached pretreatment liquid is applied to the recording surface of the sheet 13 pressed against the application roller 22 by the pressure roller 23 and sent to the U-turn reversing path 24.

  FIG. 3 shows a liquid supply stop state in which the pretreatment liquid is not supplied to the application roller 22. As described above, the absorber sticks 51 and 54 are urged together with the pan 52 by the spring member or the like in the direction of being pressed against the application roller 22. The pressing by the urging force can be easily interrupted by mechanical means, and the absorber stick 54 can be moved away from the application roller 22 as shown. As a result, the pretreatment liquid is not supplied to the application roller 22. The meaning of the liquid supply stop state in this way is to save the pretreatment liquid by performing the recording without applying the pretreatment liquid to the sheet 13 in the case where the recording is trial printed.

  Hereinafter, the first conveyance route for non-application / single-sided recording, the second conveyance route for single-sided application / single-sided recording, and the third conveyance route for double-sided application / double-sided recording are selected and combined for each case.

  When an image is recorded on one side only on the first surface, for example, the surface of the sheet 13 without applying the pretreatment liquid, the first transport route is selected and functions.

  That is, in the first feeding unit 10, a plurality of sheets 13 stacked on the pressure plate 12 are separated one by one by the feeding roller 11 and sent out in the normal rotation direction that is the image recording area direction. The conveyance route to the conveyance roller 31 that conveys the sheet 13 includes a feeding path 37 and a rush path 26. A feeding auxiliary roller 36 is disposed in the middle of the feeding path 37 and is connected to a driving source (not shown) that rotationally drives the feeding roller 11 via a one-way gear, thereby conveying the sheet 13 in the forward rotation direction. Assist when necessary. The sheet 13 is conveyed to the recording unit 30 by the feeding auxiliary roller 36 and the feeding roller 11. The recording unit 30 performs recording on the first surface, for example, the surface of the sheet 13 by reciprocating the recording head 41. When the recording on the first surface is completed and the sheet 13 is discharged out of the apparatus main body by the pair of discharge rollers 33 and 34, the recording of only the first surface of the sheet 13 is performed without applying the pretreatment liquid. That is, one-sided recording is completed.

  Next, when an image is recorded on only one surface of the sheet 13 after the pretreatment liquid is applied, the second transport route is selected and functions.

  That is, in the first feeding unit 10, the sheets 13 stacked on the pressure plate 12 are separated one by one by the feeding roller 11 and sent out toward the image recording area. The fed sheet 13 is conveyed to the recording unit 30 via the feeding path 37 and the entry path 26. The recording unit 30 passes the sheet 13 as it is without recording an image on the conveyed sheet 13. When the photo sensor 38 detects the trailing edge of the sheet 13 that is passing, conveyance in the forward rotation direction is stopped with the trailing edge of the sheet 13 being sandwiched between the conveyance roller 31 and the pinch roller 32. Subsequently, when the conveyance roller 31 is driven to rotate in the reverse direction, the sheet 13 is fed back in the backward direction. Since the conveyance surface of the reversing base 28 is substantially flush with the platen that forms the printing surface, the sheet 13 is fed back in the direction of the entry path 26 with its own rigidity, that is, waist strength. Without being carried out, it is smoothly fed back in the direction of the inversion base 28.

  The reversing base 28 where the sheet 13 starts to be fed backward, and the place where the pair of oppositely conveying rollers 31 and the pinch rollers 32 that are rotated in reverse are arranged is a “merging point” between the first conveying route and the second conveying route. . The conveyance path extending from the merging point toward the recording unit 30 on the downstream side can be called a “common conveyance section” shared by the first conveyance route and the second conveyance route. In this common conveyance section, a recording unit 30, a paper discharge roller 33, a paper discharge path 39, and the like are provided.

  The second transport route communicates with the reversing base 28 and includes a U-turn shaped reversing unit 24. That is, the sheet 13 that has been fed back from the reversing base 28 passes between the application roller 22 and the pressure roller 23 that follows the application roller 22, and the pretreatment liquid is directed downwardly of the sheet 13 when passing. Applied to the surface. The sheet 13 that has been applied to the first surface is reversed by the U-turn shape reversing unit 24 and reaches the entry path 26 again, and the first surface to which the pretreatment liquid has been applied is directed upward, and in this state, the confluence is reached. Head. Here, the conveying roller 31 is driven to rotate forward again and is fed into the recording unit 30 while sandwiching the sheet 13 in cooperation with the pinch roller 32. The recording head 41 performs a required recording on the first surface of the sheet 13 to which the pretreatment liquid has been applied. When the recording head 41 finishes recording and is discharged by the discharge rollers 33 and 34, only one side of the sheet 13 is provided. Recording ends.

  On the other hand, in the case of double-sided recording in which the pretreatment liquid is applied to each of the first and second surfaces which are both front and back surfaces of the sheet 13 and images are recorded on both the first and second surfaces, Three transport routes are selected and function.

  The operation until the image is recorded after the pretreatment liquid is applied to the first surface of the sheet 13 is the same as that in the second transport route. Therefore, when the image recording on the first surface of the sheet 13 is completed by the recording unit 30, the conveying roller 31 and the pinch roller 32 are again driven to rotate reversely without being discharged at this stage, so that the sheet 13 is reversed. It is sent back to 28. The sheet 13 passes between the application roller 22 and the pressure roller 23, and the pretreatment liquid is applied to the back surface of the sheet, that is, the second surface of the sheet 13 facing downward while passing. The sheet 13 that has been applied to the second surface is fed into a U-turn-shaped reversing unit 24. The sheet 13 which is reversed and passes the entry path 26 again and faces up on the second surface is directed to the junction. Here, the conveyance roller 31 is driven to rotate forward again to feed the sheet 13 into the recording unit 30 in cooperation with the pinch roller 32. When the image recording on the second surface of the sheet 13 is completed, the sheet discharge rollers 33 and 34 are driven to rotate forward, the sheet 13 is discharged out of the apparatus main body, and the double-sided recording ends.

(Second Embodiment)
FIG. 4 shows an image recording apparatus according to the second embodiment. In order to clarify the difference from the first embodiment, the corresponding members are denoted by the same reference numerals, and description of overlapping portions is omitted.

  In the present embodiment, a second feeding unit (second feeding unit) 60 is provided separately from the first feeding unit 10 shown in the first embodiment. A pressure plate 56 and a feeding roller 57 for feeding the sheet 55 stacked and stored in the second feeding unit are provided. The conveyance path 62 has a loop structure that largely detours from the conveyance roller 31 via the coating unit 20 and returns to the conveyance roller 31 again. That is, the conveyance path 62 includes a conveyance path 62 c from the conveyance roller 31 to the feeding roller 11, a conveyance path 62 a from the feeding roller 11 to the application roller 22, and a conveyance path 62 b from the application roller 22 to the conveyance roller 31. It is made up of. The feeding roller 11 and the application roller 22 are arranged as close as possible so that the conveyance path 62a does not become longer than necessary. The conveyance path 63 extends from the second feeding unit 60 in the direction of the conveyance roller 31 and joins the conveyance path 62. Flap guides 58, 59 and 61 are arranged in the conveyance paths 62 and 63, and the conveyance paths 62 and 63 are arranged to restrict the passage of the sheets 55 that are separated and fed one by one from the second feeding unit 60. Switchable each time. The flap guides 58, 59, 61 are arranged so as to be rotatable around the respective rotation support shafts 58a, 59a, 61a, and traffic control such that one of the conveying paths 62, 63 is cut off and the other is opened so that the sheet can pass therethrough. To function.

  Here, the coating unit 20 of the present embodiment is configured as follows. In this case, a cap 25 is provided. The cap 25 is an elastic body extending in the longitudinal direction of the application roller 22 and is pressed against the application roller 22 by a biasing means. A concave portion 25a is formed in a portion where the cap 25 abuts the application roller 22, and a sealed space is formed in a state where the cap 25 is pressed by the urging force, and is filled with the pretreatment liquid supplied from the pretreatment liquid tank. When the application roller 22 rotates, the pretreatment liquid is applied to the surface of the application roller 22 with a film thickness determined by the wettability of the roller surface of the application roller 22, the urging force of the cap 25, the viscosity of the pretreatment liquid, and the like. It is transferred to the sheet 13 or 55 and applied. The cap 25 and the pressure roller 23 can be moved away from the application roller 22.

  As shown in FIG. 5, a gear 64 is rotatably coupled to one end of the rotating shaft of the application roller 22, and sector gears 65 and 66 are fitted to both ends of the roller rotating shaft. Yes. The sector gears 65 and 66 are rotatably supported on the rotation shaft of the application roller 22, and are constituted by gear portions 65a and 66a, dowels 65b and 66b, and cams 65c and 66c. When the sector gears 65 and 66 rotate in the direction of the arrow in the figure, the cam portions 65c and 66c push up the pressure roller 23 (not shown) to separate from the application roller 22. Furthermore, after rotating in the same direction and releasing the pressing of the pressure roller 23 by the cam portions 65c and 66c, the dowels 65b and 66b abut against guide members 68 and 69 described later, and the cap 25 is resisted against the pressing force. Separated from the application roller 22. The cap support member 67 that supports the cap 25 is pressed against the application roller 22 by an urging means integrally with the cap 25, and guide members 68 and 69 are fixed to both ends in the longitudinal direction of the member. A guide groove is formed in each of the guide members 68 and 69, and the guide members 68 and 69 are fitted to the application roller 22 to guide the cap 25 to be surely brought into contact with the outer peripheral surface of the application roller 22.

  Similarly, in FIG. 5, a rod 70 having a spline shaft shape is provided, and gears 71, 72, and 73 are integrally coupled to both ends of the rod so as to be rotatable, and are rotatably supported by a housing (not shown). The gears 71 and 72 mesh with the gear portions 65a and 66a of the sector gears 65 and 66, and the sector gears 65 and 66 rotate by the same amount in the same direction by the rotation of the rod 70. The gear 74 transmits a rotational force from the driving source to the gear 64 and has a planetary gear 75. The planetary gear 75 is configured such that the revolution position is forcibly determined. The planetary gear 75 is usually located at a position shown in the figure where it is not connected to any gear and revolves to connect to the gear 73. The operation lever 76 is coupled and fixed to one end of the rod 70 and is usually not visible from the outside and is accommodated in the exterior side plate of the image recording apparatus. For example, when handling a sheet jam (jam) or the like, when the cover of the exterior side plate is opened and opened, the operation pedal 76a of the operation lever 76 is exposed.

  In the above configuration, the image recording apparatus of the second embodiment operates as follows.

  The first to fourth conveyance routes are selected in accordance with the case where the sheet 13 is fed from the first feeding unit 10 or the sheet 55 is fed from the second feeding unit 60. The Further, depending on whether the surface to be recorded by applying the pretreatment liquid to the sheets 13 and 55 is only one side or both sides, or the side to be recorded without application is only one side or both sides, the first to fourth Each transport route is selected and combined as follows.

  The first transport route is selected and functions in the case of single-sided recording in which recording is performed after applying the pretreatment liquid to one side of the sheet 13 fed from the first feeding unit 10. The operation in this case conforms to the operation of the second transport route in the first embodiment.

  That is, the sheets 13 that have been separated and fed one by one from the first feeding unit 10 are regulated by the flap guide 58 and guided to the transport path 62a. From the conveyance path 62a to the application roller 22, the pretreatment liquid is applied to the first surface, which is the surface of the sheet 13, and then the sheet 13 is sent out to the conveyance path 62b (common conveyance section). The sheet 13 reaches the conveyance roller 31 with the first coated surface directed toward the recording head 41 and guided by a flap guide 59 disposed near the end of the conveyance path 62b. Then, an image is recorded on the coated first surface of the sheet 13 by the recording head 41. Since the first transport route is for recording on one side only, when the recording on the first side is finished, the sheet 13 is discharged as it is, and the single side recording is finished.

  Similarly, the second transport route is selected and functions when double-sided recording is performed on the first and second surfaces after the pretreatment liquid is applied to the sheet 13 fed from the first feeding unit 10. .

  The operation up to the recording operation by applying the pretreatment liquid to the first surface of the sheet 13 separated and fed one by one from the first feeding unit 10 is the same as in the case of the first transport route. When the recording on the first surface is completed by the recording head 41, the sheet 13 is not discharged, and the flap guide 61 is operated by the drive source to switch the conveyance path. Subsequently, the transport roller 31 and the paper discharge roller 33 rotate reversely, and the sheet 13 is reversely fed and moved backward. However, since the conveyance path is switched by the flap guide 61, the sheet 13 does not enter the conveyance path 62b (common conveyance section) but is guided toward the conveyance path 62c. Thereafter, the sheet 13 is guided while being restricted by the flap guide 58, and the sheet 13 is conveyed from the conveyance path 62 c to the conveyance path 62 a and eventually reaches the application roller 22. The pretreatment liquid is applied by the application roller 22 to the second surface, that is, the uncoated surface, which is the back surface of the sheet 13, and after application, reaches the conveyance roller 31 through the conveyance path 62 b. The recording head 41 performs recording on the second surface of the sheet 13, and after recording, the recording head 41 is discharged out of the apparatus main body by the paper discharge roller 33, and the double-side recording ends.

  The third conveyance route is selected and functions when recording is performed on the sheet 55 fed from the second feeding unit 60 only on the first surface and in a state where the pretreatment liquid is not applied.

  The sheets 55 separated and fed one by one from the second feeding unit 60 are conveyed through the conveyance path 63, are restricted by the flap guide 59, and reach the conveyance roller 31. An image is recorded on the first surface of the sheet 55 sent to the recording head 41 by the forward rotation driving of the conveying roller 31, and is discharged out of the recording apparatus when the recording is completed. In this way, single-sided recording of only the first surface is completed without applying the pretreatment liquid to the sheet 55.

  The fourth transport route is selected when recording is performed only on the first surface of the sheet 55 that has been separated and fed from the second feeding unit 60 after the pretreatment liquid is applied to the first surface. To function.

  That is, the sheets 55 that have been separated and fed one by one from the second feeding unit 60 are transported through the transport path 63, guided by the traffic regulation by the flap guide 59, and sent to the transport roller 31. At this time, the recording head 41 is set not to perform a recording operation on the fed sheet 55. When the trailing end of the sheet 55 passes the flap guide 61 by the forward rotation driving of the conveying roller 31, the flap guide 61 is operated by a driving source to switch the conveying path. The conveyance roller 31 and the discharge roller 33 are driven in reverse rotation substantially in synchronism with this to feed the sheet 55 backward. Even if the sheet 55 is reversely fed, since the conveyance path is switched by the flap guide 61, the sheet 55 does not enter the conveyance path 62b (common conveyance section) but is guided and enters the conveyance path 62c. The sheet 55 is guided to the flap guide 58 and sent to the conveyance path 62a. When the application roller 22 on the conveyance path 62a is reached, the pretreatment liquid is applied to the first surface of the sheet 55 to be recorded. The coated sheet 55 circulates in the conveyance path 62b and reaches the conveyance roller 31 again. At this time, the conveying roller 31 is driven to rotate forward to feed the sheet 55 to the recording head 41 in cooperation with the pinch roller 32. Recording on the first surface of the sheet 55 is performed by the recording head 41, and the recorded sheet 55 is discharged out of the apparatus main body by the discharge roller 33, and the one-side recording on the first surface is finished.

  However, the fourth conveyance route is used when recording is performed after applying the pretreatment liquid on the second surface of the sheet 55 separated and fed from the second feeding unit 60, that is, the first and second sides of the sheet. Of course, it is also possible to record an image by applying a pretreatment liquid to each of the surface and the second surface. In that case, the conveyance path is switched again by the flap guide 61 so that the sheet 55 is not discharged after the application recording on the first surface, and the conveyance roller 31 and the discharge roller 33 are driven in reverse rotation. As a result, the sheet 55 is fed into the conveyance paths 62c, 62a and 62b, and after the pretreatment liquid is applied to the second surface, the image is recorded and then discharged, and the duplex recording on the first surface and the second surface is completed. To do.

  By the way, when an image is recorded without selectively and intentionally applying the pretreatment liquid to the sheet 55, the following operation is performed. After the pretreatment liquid in the cap 25 is collected and emptied, the planetary gear 75 is rotated counterclockwise to rotate the gear in the direction opposite to the arrow in the figure, and the rod 70 is rotated counterclockwise, via the sector gears 65 and 66. The cap 25 moves away from the application roller 22. In this state, the pressure roller 23 is pressed against and contacts the application roller 22, so that the application roller 22 does not apply the pretreatment liquid to the sheet 55, but a conveying force can be generated. Therefore, even when a conveyance path that passes through the conveyance path 62 is selected, an image can be recorded without applying the pretreatment liquid. After recording, when the gear is rotated in the direction of the arrow in the figure, the rod 70 rotates clockwise and the cap 25 abuts against the application roller 22 again. If the planetary gear is forcibly rotated clockwise and the cap 25 is filled with the pretreatment liquid, the pretreatment liquid can be applied by the application roller 22.

  Further, when a paper jam (jam) occurs while the application roller 22 holds the sheet 55 in the conveyance path 62a, the following operation is performed to perform jam processing. When the jam treatment cover is opened, the operation portion 76a of the operation lever 76 is exposed. When the operation lever 76 is rotated counterclockwise, the rod 70 integrally rotates counterclockwise. The operation lever 76 can mechanically regulate the amount of operation thereof. Even if the pressure roller 23 is separated from the application roller 22, the cap 25 stops in contact with the transport roller. In this state, since the restraint of the sheet 55 by the pressure roller 23 is released, the sheet 55 can be taken out. Further, since the cap 25 remains in contact with the application roller 22, there is no need to collect the pretreatment liquid. When the left rotation of the operation lever 76 is released, the cap 25 and the pressure roller 23 are brought into contact with the application roller 22 by the respective pressing forces, and the initial state is restored.

  As described above, the sheet 55 fed from the second feeding unit 60 is conveyed by selecting one of the first to fourth conveyance routes. At that time, when recording is performed after application of the pretreatment liquid or after non-application, it is required to feed the sheet at a substantially constant speed when applying with the application roller 22. If the sheet feeding speed is not uniform, unevenness occurs on the coated surface. Further, during recording, when the recording head 41 is moving in the main scanning direction, the sheet 55 is stopped. Accordingly, the conveyance path 62c is expected to be longer than the length of the sheet 55, and is set to start recording by the recording head 41 after applying the pretreatment liquid over the entire sheet. Therefore, it is desirable to set the portion where the conveyance path 62a extending from the feeding unit 60 joins the conveyance path 62c as short as possible.

  Although the first and second embodiments have been described above, the present invention is not limited to these embodiments. Other embodiments, applications and modifications, and combinations thereof are possible within the scope not departing from the gist of the present invention.

  For example, as described above, the operation lever 76 is operated to retract the pressure contact roller 23. However, the rod 20 rotates in a required direction in conjunction with the opening of the jam processing cover, and the pressure contact roller 23 is interlocked with the operation. A structure in which it is retracted is also possible.

  In addition, although common to the above-described embodiments, the conveyance path for feeding the sheets 13 and 55 immediately after the application by the application roller 22 is desirably a substantially curved surface with the applied sheet surface being concave. A layer to which the pretreatment liquid is applied is formed on the sheets 13 and 55 immediately after passing through the application roller 22. The coating layer may touch the road surface of the conveyance path, or the pretreatment liquid of the coating layer may scatter due to sheet running vibration during conveyance, and may adhere to the conveyance path surface although it is a small amount. When the adhering pretreatment liquid is dried, the conveyance path has a larger conveyance resistance than the normal conveyance surface, and the resistance distribution is uneven. If the leading edge of the sheet rubs and moves on the uneven conveying surface, the sheet edge may be caught and the sheet may be partially curled or skewed. Since the pretreatment liquid is normally absorbed into the sheet quickly in about 100 to 200 milliseconds, the above adhesion occurs within a few centimeters from the application roller 22. In anticipation of this, by forming the conveyance path extending downstream from the application roller 22 into a concavely curved surface, the leading edge of the sheet can be conveyed on the concave conveyance surface without adhesion of the pretreatment liquid.

1 is a diagram showing a preferred embodiment of an image recording apparatus according to the present invention. The figure which shows the structure of the application | coating mechanism of 1st Embodiment. The figure which shows the non-supply state of the pre-processing liquid in this application | coating mechanism. The figure which shows 2nd Embodiment. The perspective view which shows a part of said 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording apparatus 10 1st feeding unit (1st feeding part)
11, 57 Paper feed roller 13, 55 Sheet 20 Coating unit (coating means)
22 Application roller (application mechanism)
23 Pressure roller (coating mechanism)
24 U-turn reversing path (common transport section)
25 Cap 26 Entry path 28 Reverse rotation base 30 Recording unit (image recording means)
31 Conveying rollers 33, 34 Paper discharging rollers 37 Feeding path 38 Photo sensor 41 Recording head 42 Carriage 43 Slide shaft 44 Slide rail 51, 54 Absorber stick (coating mechanism)
52 Pan (coating mechanism)
53 Pretreatment liquid bag 58, 59, 61 Flap guide 60 Second feeding unit (second feeding unit)
62, 63 transport path 62b transport path (common transport section)

Claims (6)

In an image recording apparatus in which a pretreatment liquid containing a compound that insolubilizes a colorant in a recording liquid is applied to a recording area of a sheet by an application means, and an image is recorded in the recording area after application by an image recording means.
A common conveyance section shared by at least two of a plurality of selectable and combinable conveyance routes for conveying a sheet to the image recording means is provided, and the coating means is provided in the common conveyance section. Image recording device. An image recording apparatus according to claim 1, wherein a reversing unit is provided in the common conveyance section to reverse the front and back of the sheet fed back from the image recording unit and return the sheet to the image recording unit again. The plurality of transport routes are
A first conveyance route for conveying the sheet fed from the first feeding unit to the image recording means and performing single-sided recording only on the first surface;
The sheet fed from the first feeding unit is sent to the common conveyance section, the pretreatment liquid is applied to the first surface by the coating unit, and then the sheet is reversed by the reversing unit. A second transport route for transporting to the means and performing single-sided recording only on the first surface;
A third transport route for performing recording by applying to both sides of the sheet by repeating each operation of single-sided coating and single-sided recording in the second transport route;
The image recording apparatus according to claim 2, comprising: In addition to the first feeding unit, a second feeding unit is provided, and any one of the first to third transport routes is selected, or the fourth transport route is a combination of these transport routes. The image recording apparatus according to claim 3, wherein the sheet fed from the two feeding unit is conveyed to the image recording unit to perform single-sided recording or double-sided recording. The image recording apparatus according to claim 1, wherein the coating unit includes a liquid supply stop mechanism that interrupts the supply of the pretreatment liquid. 6. The application means includes an application roller impregnated with a pretreatment liquid, and the supply of the pretreatment liquid to the application roller is interrupted by the liquid supply stop mechanism. The image recording apparatus described in 1.

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