JP6314638B2 - Coating apparatus and image forming system - Google Patents

Description

  The present invention relates to a coating apparatus that coats a processing liquid in an image forming system, and an image forming system.

  2. Description of the Related Art Inkjet image recording methods are rapidly spreading due to the advantages of low noise, low running cost, and easy colorization. However, when recording on media other than special paper, in addition to initial quality problems such as bleeding, density, color tone and show-through, there were problems related to image robustness such as water resistance and weather resistance. Various proposals to solve were made.

  As one of those solutions, there is a method of improving image quality by applying a treatment liquid having a function of aggregating ink immediately before ink droplets adhere to a recording medium.

  As one method for applying the treatment liquid, a method of applying the treatment liquid to the entire paper surface using a roller is known. In a coating apparatus that applies a processing liquid onto a sheet using a roller, the processing liquid is pumped up by rotation of a squeeze roller driven by a motor. The processing liquid pumped up by the squeeze roller is scraped off partly by the nip between the application roller and the squeeze roller covered with an elastic body such as rubber. The remaining liquid is thinly and evenly on the application roller. To be extended to. The processing liquid drawn on the application roller is transferred to a sheet sandwiched between the pressure roller and the application roller. (For example, Patent Document 1)

  In addition, in the coating device having such a configuration, the roller easily wears at the end of the paper, and when the paper width is changed, problems such as white spots where the worn part is not applied and liquid accumulation in which the liquid accumulates in the worn part occur. There are things to do. As a countermeasure, the position of the coating unit is swung by a moving mechanism with respect to the transport direction, which is the paper travel line, during printing, thereby preventing the wear at the edge of the paper from concentrating on the same location and affecting the wear. There is technology to disperse.

  However, the above-described coating apparatus has a configuration in which the latch of the moving mechanism is hooked on a pin fixed to the coating unit because the unit must be easily detachable from the apparatus body during operation and maintenance. However, when the application unit is mounted out of the normal position, or when the moving force is not transmitted at the switching point of the movement direction when the application unit is moved, the latch does not hook correctly. There was a thing. If the latch is not correctly applied, the moving force is not transmitted and the switching cannot be performed smoothly, and there is a possibility that the wear of the application roller may partially advance only at this position.

  In view of the above circumstances, an aspect of the present invention provides a treatment liquid coating apparatus using a roller that can suppress partial wear of the roller by securely holding a unit including the roller. Objective.

In order to solve the above-described problem, in one aspect of the present invention, the coating apparatus sandwiches the recording medium between the coating roller and a coating unit that has a coating roller that applies a treatment liquid to a transported recording medium. A pressure roller; and a moving mechanism that moves the coating unit in a direction perpendicular to the conveyance direction of the recording medium. The moving mechanism includes a first latch that holds the coating unit in a connectable manner, and the first latch A second latch for holding one latch is provided, and the coating unit is detachable from the coating device.

  In one embodiment of the present invention, in a treatment liquid coating apparatus using a roller, partial wear of the roller can be suppressed by reliably holding the unit including the roller.

1 is a schematic diagram illustrating a flow of an inkjet image forming system according to an embodiment of the present invention. It is a schematic block diagram of the processing agent liquid coating apparatus used for the image forming system which concerns on one Embodiment of this invention. It is a schematic diagram which shows the structure of the application | coating mechanism contained in the processing agent liquid application apparatus of FIG. It is a top view which shows the structure of the coating unit, moving mechanism, and latch mechanism which concern on this invention. It is a top view which shows the structure of the moving mechanism and latch mechanism which concern on this invention. It is an enlarged top view which shows the structure of the latch mechanism which concerns on this invention. It is a figure which shows the relationship between the application | coating mechanism, moving mechanism, latch mechanism, and load concerning this invention. It is a figure which shows the structure of the moving mechanism and latch mechanism in a comparative example.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of the present invention. More specifically, FIG. 1 is a schematic diagram showing a part of an inkjet image forming system (inkjet printing system) 1000 according to an embodiment of the present invention.

  As shown in FIG. 1, a recording medium (recording medium) W made of paper such as continuous paper fed from a paper feeding device 100 is sent to a pretreatment device 101 including coating devices 33 and 34. The pretreatment apparatus 101 applies a treatment liquid (pretreatment liquid), which is a coating material having a function of aggregating the ink that has landed on the recording medium onto the image forming surface of the recording medium W. Depending on the desired printed matter, the surface on which the treatment liquid is applied may be only one side or both sides.

  Next, the recording medium W is sent to a first inkjet printer (recording apparatus) 102 located downstream of the preprocessing apparatus 101 in the conveyance direction of the recording medium W, and ink droplets are applied to the surface of the recording medium W on which the pretreatment liquid is applied. Is ejected to form a desired image. When performing double-sided printing, the front and back of the recording medium W are then reversed by a reversing device (not shown), and the recording medium W is subsequently fed into a second ink jet printer (not shown) to drop ink droplets on the back side of the recording medium W. A desired image is formed by discharging. After such image formation, the image is sent to a post-processing device (not shown) and subjected to predetermined post-processing.

  FIG. 2 is a schematic configuration diagram of a pretreatment apparatus (pretreatment liquid coating / drying apparatus) 101 used in the image forming system 1000 according to an embodiment of the present invention.

  Next, the preprocessing apparatus 101 will be described with reference to FIG. The pretreatment apparatus 101 includes a pretreatment liquid application unit 330 including application apparatuses 33 and 34 that apply the pretreatment liquid to the recording medium W. In order to dry the pretreatment liquid of the recording medium W, a heating unit (recording medium heating apparatus) 350 is provided downstream of the pretreatment liquid application unit 330 in the recording medium conveyance direction.

  The pretreatment apparatus 101 further includes an air loop unit 320, a pretreatment liquid supply unit 340, and a dancer unit 380.

  The air loop unit 320 includes a guide roller 321 that is rotatably supported, a feed-in (FI) roller 322 that sandwiches and conveys the recording medium W, and an FI nip roller 323. In the air loop unit 320, a guide roller 321, a rotationally driven FI roller 322, and a driven rotated FI nip roller 323 convey the recording medium W supplied from the paper feeding device 100, and draw the recording medium W into the air loop unit 320. . At this time, the rotation of the FI roller 322 is controlled by an optical sensor (not shown) so as to form an air loop AL in which the amount of slack of the recording medium W is constant. The recording medium W that has passed through the air loop AL is applied with a tension for stabilizing the conveyance by a tension shaft (not shown), and is conveyed to the pretreatment liquid coating unit 330.

The recording medium W that has passed through the air loop AL passes between two edge guides (not shown), and is arranged so that the longitudinal direction is orthogonal to the conveyance direction (arrow direction) of the recording medium W. Passes between the pass shafts 325 in an S shape. The two pass shafts 325 are supported by the edge guide, and the distance between the pair of edge guides is approximately the same as the width direction of the recording medium W. The edge guides are fixed to the pass shaft 325 so as to be movable, for example, by fixing means such as screws, and the distance between the edge guides is adjusted according to the width dimension of the recording medium W to be used. By the action of these pass shafts and edge guides orthogonal thereto, the travel position in the width direction of the recording medium W is restricted, and stable travel is possible.
The recording medium W that has passed between the pass shaft 325 and the edge guide is given a tension for stabilizing the conveyance by a tension shaft (not shown) in a fixed state.

  The pretreatment liquid coating unit 330 includes an infeed roller 331, a feed nip roller 332, a back surface coating mechanism 33, and a surface coating mechanism 34 that are rotationally driven. Further, the pretreatment liquid coating unit 330 is provided with a coating control unit 81 and a swing control unit 82 shown in FIG. 3 in order to control the back surface coating mechanism 33 and the front surface coating mechanism 34. In the vicinity of the pretreatment application unit 330, an outfeed roller 335 and a feed nip roller 336 that are rotationally driven are provided.

  The feed nip roller 332 sandwiches and conveys the recording medium W with the infeed roller 331, and the feed nip roller 336 sandwiches and conveys the recording medium W with the outfeed roller 335. The in-feed roller 331 and the feed nip roller 332 serve as a conveying unit.

  The back surface application mechanism (application device) 33 includes a squeeze roller 337, an application roller 338, and a pressure roller 339. The recording medium W transported to the back surface coating mechanism 33 is sandwiched and transported between the application roller 338 to which the pretreatment liquid is supplied by the squeeze roller 337 and the pressure roller 339, and is applied to one side ( A pretreatment liquid is applied to the back surface side. The pressure roller 339 is provided in the pressure unit 14r, and the squeeze roller 337 and the application roller 338 are provided in the application unit 15r. The recording medium W that has passed through the back surface application mechanism 33 is conveyed to the front surface application mechanism 34.

  The surface application mechanism (application device) 34 includes a squeeze roller 347, an application roller 348, and a pressure roller 349, and applies the pretreatment liquid to the outer surface (surface) side of the recording medium W. The pressure roller 349 is provided in the pressure unit 14f, and the squeeze roller 347 and the application roller 348 are provided in the application unit 15f. The recording medium W that has passed through the surface coating mechanism 34 is conveyed to a heating unit 350 that is a heating device by an outfeed roller 335 and a feed nip roller 336.

  Note that the back surface application mechanism 33 and the front surface application mechanism 34 are controlled to operate selectively, and the recording medium W is applied with a pretreatment liquid on one or both of the front surface and the back surface.

  The pretreatment liquid supply unit 340 stores the pretreatment liquid and appropriately supplies the pretreatment liquid to the back surface application mechanism 33 and the front surface application mechanism 34.

  The heating unit 350 includes heating rollers 540a, 540b, 550a, 550b, 560a, and 560b from the upstream in the conveyance direction of the recording medium W, and further includes a discharge conveyance roller 70 and a control device 80. In the heating unit 350, control processing by the control device 80 is executed, and the heating amounts (temperatures) of the heaters 541a to 561b of the respective heating rollers 540a to 560b are controlled.

  The recording medium W is wound around the heating rollers 540a to 560b in a zigzag manner, and is conveyed through the heating unit 350 by the outfeed roller 335 and the feed nip roller 336, and the feed roller 359 and the feed nip roller 360. . Each of the heating rollers 540a to 560b rotates following the recording medium W being conveyed, and heats the recording medium W to dry the pretreatment liquid applied to the recording medium W.

  In the heating unit 350, each of the heating rollers 540a to 560b is configured to rotate following the recording medium W. For example, it is not necessary to provide a motor or the like as a driving means for driving each heating roller to rotate, and the motor installation space is omitted, and the size can be reduced.

  The recording medium W from which the pretreatment liquid applied to the surface in the heating unit 350 is dried is sandwiched between the feed roller 359 and the feed nip roller 360 that are rotationally driven, and conveyed to the dancer unit 380.

  Note that there may be a configuration in which the heating unit 350 is not provided when a quick-drying type is used depending on the type of coating liquid or recording medium used, or when the installation space of the pretreatment apparatus 101 is taken into consideration. In this configuration, the recording medium 10 that has exited the back surface application mechanism 33 and the front surface application mechanism 34 is directly conveyed to the dancer unit 380.

  The dancer unit 380 includes two guide rollers 381 and 382, a movable frame 384, position detection means (not shown) for detecting the position of the movable frame 384, and two dancer rollers 385 and 386 rotatably attached to the movable frame 384. Have. The movable frame 384 is provided with a weight 383 at the bottom, and is movable with the dancer rollers 385 and 386 in the direction of arrow A. The recording medium W is wound around the two guide rollers 381 and 382 and the two dancer rollers 385 and 386 in a W shape.

  The dancer unit 380 adjusts the vertical position of the movable frame 384 by controlling the conveyance amount of the feed roller 359 based on the output of the position detection means (not shown). By adjusting the position of the movable frame 384, a buffer for the recording medium W between the pre-processing device 101 and the first inkjet printer 102 at the subsequent stage is secured.

  The recording medium W heated by the heating unit 350 is cooled by the dancer unit 380 and then conveyed to the first inkjet printer 102 at the subsequent stage.

  With such a configuration, the pretreatment apparatus 101 applies the pretreatment liquid to the recording medium W and conveys it to the first inkjet printer 102 at the subsequent stage. By applying the pretreatment liquid to the recording medium W by the pretreatment apparatus 101, it is possible to prevent ink bleeding, density, color tone, and show-through in the subsequent image formation, and to improve the image quality by assisting the penetration. it can.

  FIG. 3 is a schematic diagram showing the configuration of the coating mechanism 33 based on an embodiment of the present invention. As the coating mechanism 33, there are the back surface coating mechanism 33 and the surface coating mechanism 34 shown in FIG. 2, and the structure of the mechanism is the same. In the coating mechanisms 33 and 34, the pressurization units 14f and 14r and the coating units 15f and 15r have the same structure, and hence the description thereof will be omitted.

  The application mechanism 33 includes a pressure mechanism 14 and a movement mechanism 30 serving as a swing mechanism in addition to the application unit 15. The application mechanism 33 is connected to an application control unit 81 and a swing control unit 82. Further, the coating unit (processing liquid container) 15 of the coating mechanism 33 is connected to a pre-processing liquid supply unit (cartridge) 340 that replenishes the processing liquid.

  The squeeze roller 337, the application roller 338, and their peripheral members are mounted on the application unit 15, and the pressure roller 339 and its peripheral member are mounted on the pressure unit 14. The application control unit 81 receives an operation instruction related to printing from a controller (not shown) of the image forming system 1000 and controls members in the application unit 15 in the application mechanism 33 and members in the pressure unit 14. The amount of pretreatment liquid applied is adjusted.

  The treatment liquid stored in the pretreatment liquid supply unit 340 is supplied from the supply unit 22 through the supply path 22 by a pump 21 that is electrically driven liquid supply such as a tubing pump or a diaphragm pump. 23.

  Next, the processing liquid L stored in the supply pan 23 is pumped up by the rotation of the squeeze roller 337 driven by the application amount adjusting motor 24a of the motor unit 24 through the gear 24b. As the squeeze roller 337, for example, an anilox roller or a wire bar having a grooved surface is used. Even when the viscosity or the printing speed of the processing liquid L changes, the processing liquid during pumping is used. The pumping amount of L becomes difficult to be affected.

  Here, the anilox roller is a metal roller in which fine grooves are formed on the surface used for printing, papermaking and the like, and the shape of the grooves is various such as a triangular shape or a pyramid shape called a pyramid shape. For normal rollers without grooves, the amount of liquid becomes unstable due to various factors such as printing speed and liquid viscosity, but the anilox roller increases the amount of liquid passing between the rollers by carving grooves, speed, Stabilizes the amount of liquid that passes even when there is a disturbance such as viscosity.

  You can also use a wire bar with various thicknesses of wire wrapped around a metal roller, but because of problems such as unraveling the wire, an anilox roller that forms a groove shape directly on the metal roller is a squeeze roller 337 is more preferable.

  The processing liquid L pumped up by the squeeze roller 337 is in contact with the squeeze roller 337 and the application roller 338 whose periphery is covered with an elastic body such as rubber so that the remaining liquid is thinly and uniformly stretched on the application roller 338. Part of the processing liquid L is scraped off by the part (NIP).

  At this time, by changing the NIP load of the application roller 338 and the squeeze roller 337, the amount of the processing liquid L to be scraped off can be controlled. The processing liquid L stretched on the application roller 338 is applied to the recording medium W sandwiched between the pressure roller 339 and the application roller 338.

  The application roller 338 is supported by the bearings 25 at both ends, and follows the recording medium W, that is, follows the conveyance of the recording medium W. At this time, under the condition that the coating amount is large and the frictional resistance with the recording medium W is low, a slip occurs between the coating roller 338 and the recording medium W, and the portion that contacts the edge portion that is the end of the recording medium W As a result, the application roller 338 is worn.

  In the pressure unit 14, the lifting mechanism 26 is attached to both ends of the pressure roller 339, and when the processing liquid L is not applied, the pressure roller 339 is retreated upward and the application roller 338 and the pressure roller 339. The contact state (NIP) between the two can be canceled.

  The pressure unit 14 including the pressure roller 339 is detachably fixed to the housing 10. That is, the pressure roller 339 is fixed to the housing 10 so as to be rotatable.

  The coating unit 15 which is a processing liquid storage container stores the processing liquid, and fixes the coating roller 338 and the squeeze roller 337 inside so as to be rotatable. The coating unit 15 is provided in the housing 10 so as to be movable (swingable) in the width direction of the recording medium W (in a direction orthogonal to the conveyance direction of the recording medium W).

  A part of the moving mechanism 30, the pressure unit 14, and the coating unit 15 are provided in the housing 10. The application unit 15 can be attached to and detached from the housing 10 which is a main body.

  In the embodiment of FIG. 3, the housing 10 is open at the lower left side. When the application unit 15 is attached to the application mechanism 33, the application unit 15 is inserted from the housing 10 through the opening 10o in the horizontal direction (see the arrow in the figure). When the insertion proceeds, two positioning pins 16 provided upstream and downstream in the insertion direction are inserted into holes of the positioning plate 17 provided in the housing 10 at a predetermined position, so that the recording medium conveyance direction is reached. Positioning is performed in (FIG. 3, front and back directions).

  The width direction (FIG. 3, left-right direction) of the recording medium W of the coating unit 15 is positioned by hooking the latches 60 and 64 of the moving mechanism 30 on the latch pin (fitting member) 12 fixed to the coating unit 15. The Here, the moving mechanism 30 connected to the coating unit 15 via the latch pin 12 continues the coating unit 15 having the roller (wheel) 11 on the lower surface in a direction perpendicular to the recording medium conveyance direction of the recording medium W. Or, it is rocked (moved) intermittently. The application unit 15 can move when the roller 11 rolls on the bottom surface (or a rail provided on the bottom surface) of the housing 10 according to the force of the moving mechanism 30.

  The moving mechanism 30 is a range surrounded by a one-dot chain line in FIG. 3, and includes a slider 42 as a moving member, latches 60 and 64 (see FIG. 4) and a position detection target 28 provided in the slider 42, and a screw shaft 43. A frame 40 disposed inside the housing 10 and a motor (oscillation motor) 41 fixed to the outside of the housing 10 are provided. The latch mechanism 31 is a range surrounded by a circle in FIG. 3, and includes latches 60, 64 and the like provided in the slider 42 that are involved in the fitting of the latch pin 12 of the coating unit 15.

The motor 41 fixed to the housing 10 is driven to rotate the screw shaft 43 (screw shaft), and the slider 42 slides along the screw shaft 43 in the horizontal direction and in the width direction of the recording medium W. By reciprocating the slider 42 in the above direction, the coating unit 15 connected to the slider 42 via the latch pin 12 and the latches 60 and 64 is swung.
That is, when the slider 42 (moving member) connected to the coating unit 15 (processing liquid storage container) moves, the coating unit 15 moves inside the housing 10 and the coating roller 338 provided in the coating unit 15. Swings in the width direction of the recording medium W with respect to the pressure roller 339.

A position sensor 13 arranged with a plurality of sensors such as photo interrupters arranged beside the moving mechanism 30 detects the position of the moving mechanism 30.
More specifically, since the application unit 15 has a moving width in the moving direction, which is a width that moves in the width direction of the recording medium W, the moving mechanism 30 also has a determined moving width. When the position sensor 13 outputs the end detection result of the movement mechanism 30 when the movement mechanism 30 reaches either one of both ends of the movement width, the position sensor 13 moves in the opposite direction. To be controlled.

  Further, the position sensor 13 detects, for example, the position of the position detection target 28 at the moving mechanism 30 at the end of printing, and outputs the detected position to an IC chip which is a storage means to be described later. Used.

  Here, the position sensor 13 has a plurality of sensors arranged along the moving direction of the moving mechanism 30, and the sensors at both ends of the row detect that the end of the moving width of the moving mechanism 30 has been reached. . At the end of printing, the position of the moving mechanism 30 is detected depending on which sensor among the plurality of sensors is closest or between the sensors. Further, as shown in the figure, a position detection target 28 that is used by the position sensor 13 to detect the position of the slider 42 may be provided on the slider 42 as a moving member on the moving mechanism 30 side. Although FIG. 3 shows an example in which there is one position detection target 28, a plurality of position detection targets 28 may be provided.

  The swing control unit 82 connected to the moving mechanism 30 is connected to the application control unit 81 and a controller (not shown) of the image forming system 1000. Then, the swing control unit 82 determines the moving direction of the slider 42 of the moving mechanism 30 based on information such as the coating amount determined based on the paper type and resolution, the printing speed, the detected position of the moving mechanism 30, and the like. Control moving speed and driving time.

Although not shown, an IC chip is stored in the coating unit 15, and the swing position (moving position) and swing direction (moving direction) of the coating roller 338 at the end of the previous printing are used as the IC chip. I remember it. Then, the data of the swing position and the swing direction are read from the IC chip at the next printing, and the printing starts at the swing position and the swing direction stored at the end of the previous printing. By this operation, the wear amount can be averaged within the swing range.
Then, the recording medium W coated with the processing liquid while being swung is conveyed to the heating device 350.

(Configuration of moving mechanism and latch mechanism)
FIG. 4 is a top view showing the configuration of the coating unit 15, the moving mechanism 30, and the latch mechanism 31 in the coating mechanism (coating apparatus) 33 or 34 according to the present invention. The coating unit 15 detachably attached to the coating device 33 is mounted on the left side of FIG. 3, for example, into the casing 10 of the coating device 33 from above in FIG. 4 and is connected to the moving mechanism 30. The moving mechanism 30 includes a frame 40 fixed to the coating device 33 and a slider 42 that swings in the width direction of the recording medium W during printing by a motor 41. As described above, the slider 42 is connected to the rotatable screw shaft 43, and the slider 42 slides relative to the frame 40 when the screw shaft 43 receives and rotates the power from the motor 41.

  The slider 42 is mounted with a first latch 60 that rotates about the rotation center A1 and a second latch 64 that rotates about the rotation center A2. The position of the first latch 60 is determined by the rotation center A1 and the hook position F of the spring (elastic body) 45 which is a tension spring. The position of the second latch 64 is determined by the rotation center A2 and ON / OFF of the solenoid 46.

  The first latch 60 has a bifurcated sandwiching portion with a slit and a tapered shape so that the latch pin (fitting member) 12 is easily sandwiched. A guide surface 61 that guides the insertion of the latch pin 12 of the coating unit 15 and a holding surface 62 that clamps the latch pin 12 between the abutting surface (contact surface) 44 of the slider 42 are formed inside the sandwiching portion. ing.

  In the moving mechanism 30, the abutting surface 44, the first latch 60, and the second latch 64 that are part of the surface of the slider 42 that are involved in the clamping (fitting) of the latch pin 12 are referred to as a latch mechanism 31.

  When the coating unit 15 is outside the coating device 33 or when the latch pin 12 of the coating unit 15 is not yet touching the latch mechanism 31 as shown in FIG. 4, the first latch 60 and the second latch 64 are respectively It is located at the retracted position (P1off / P2off).

  FIG. 5 is a top view showing the configuration of the moving mechanism 30 and the latch mechanism 31. FIG. 5A shows a state where the first latch 60 is in the mounted state. FIG. 5B shows a state where the first latch 60 and the second latch 64 are in a mounted state, that is, a state where the moving mechanism 30 and the coating unit 15 are connected by the latch mechanism 31.

  In the operation of inserting the coating unit 15 and connecting it to the moving mechanism 30, first, the latch pin 12 of the coating unit 15 contacts the guide surface 61 of the first latch 60. Then, while the first latch 60 rotates in the contact state, the coating unit 15 is inserted until the latch pin 12 abuts against the abutting surface 44 (upper surface) of the slider 42. At this time, when the hook position F of the spring 45 of the first latch 60 exceeds the top dead center (a position where no rotational force is generated), the latch pin 12 is subjected to the elastic force of the spring 45 applied in the direction of the abutting surface 44. Therefore, a pulling force Ts that pulls in the downward direction in FIG. Therefore, the first latch 60 rotates to the position Pon (FIG. 5A).

  Here, if the spring 45 is in a position exceeding the top dead center of the hook position F, the latch pin 12 has an elastic force in the rightward direction (curved arrow, the direction in which the latch pin 12 is sandwiched) in FIG. Is added. Therefore, even if the latch pin 12 does not abut against the abutting surface 44 of the slider 42, a pulling force that pulls the coating unit 15 into the device 33 acts. Thereafter, the second latch 64 is rotated by the solenoid 46 and hooked on the pin 63 fixed to the first latch 60, whereby the holding of the coating unit 15 is completed at the position of Pon (FIG. 5B).

  On the other hand, when the coating unit 15 is separated from the moving mechanism 30 and taken out from the coating device 33, the coating unit 15 is pulled out with the second latch 64 released (P2off). At this time, the first latch 60 is moved in the leftward direction of FIG. 4 (direction in which the latch pin 12 is released) to the retracted position (P1off) where the hook position F of the spring 45 exceeds the top dead center by the latch pin 12 of the coating unit 15. It is rotated. Thus, in a state where the coating unit 15 is outside the coating device 33, the first latch 60 is always in the retracted position P1off due to the elastic force in the releasing direction of the spring 45.

  FIGS. 6A and 6B are top views showing the relationship between the latch pin 12, the first latch 60, and the slider 42. When the coating unit 15 (see FIG. 3) is inserted, the latch pin 12 first contacts the guide surface 61 of the first latch 60 (FIG. 6A), and the latch pin 12 slides while contacting the guide surface 61. I will do it. Next, the latch pin 12 abuts against the abutting surface 44 of the slider 42. At this stage, the application unit 15 stops, but the first latch 60 is held by the elastic force in the right direction (curved arrow) in FIG. 5A of the spring 45 acting on the first latch 60. The surface 62 rotates and stops until it contacts the latch pin 12 (FIG. 6B). At this time, the guide surface 61 of the first latch 60 is not in contact with the latch pin 12, and the latch pin 12 of the coating unit 15 is located between the abutting surface 44 of the slider 42 and the holding surface 62 of the first latch 60. And it is pinched without a gap.

  By fitting in this way, the load of the connecting operation is mainly applied to the first latch 60, and the fitting state of the latch pin 12 is maintained by the elastic force of the spring 45 arranged along the first latch 60. The The second latch 64 is installed so as to enhance the safety of maintaining the fitted state, and is used in an auxiliary manner by the solenoid force of the solenoid 46 acting so as to assist the holding state of the first latch 60. Is done. Thus, in the design state, the latch pin 12 of the application unit 15 is sandwiched between the abutting surface 44 of the slider 42 and the holding surface 62 of the first latch 60 in the fitted state without any gap, and the pin 63 and the second latch 64 are also fitted with no gap.

  However, the coating unit 15 may be replaced due to maintenance or the like, and if it is replaced, a slight error in the dimensions of the latch pin 12 may occur. Alternatively, it is conceivable that the latch mechanism 31 has some play in the fitted state so that it can cope with errors. For example, when the latch pin 12 is thin, the latch pin 12 is clamped between the abutment surface 44 of the slider 42 and the holding surface 62 of the first latch 60 without a gap by the pulling force of the spring 45. However, the position of the pin 63 in the state of the first latch 60 is lowered by the amount that the latch pin 12 is thin, and there is a possibility that a gap G is generated by the fitting between the pin 63 and the second latch 64.

  FIG. 7 shows the pulling force Ts in the direction in which the latch pin 12 is pulled by the first latch 60, the nip load applied to the coating roller 338, and the weight of the coating unit 15 during the movement of the coating unit 15, in the direction opposite to the tensile force Ts. It is a side view showing the relationship with the load Tp which acts.

  In this latch mechanism 31, when a moving force is applied in the Tp direction of FIG. 7, the latch pin 12 is pressed in contact with the abutting surface 44 of the slider 42, whereby the moving force of the moving mechanism 30 is transmitted. When a moving force is applied in the Ts direction, the latch pin 12 is pulled in contact with the holding surface 62 of the first latch 60, whereby the moving force of the moving mechanism 30 is transmitted.

  In the present invention, the pulling force in the Ts direction of the spring 45 of the first latch 60 is designed to be larger than the load accompanying movement, conversion of the moving direction, and stopping. More specifically, when moving in the Tp direction, the latch 60 does not rotate and the state shown in FIG. 6B can be maintained even if the latch pin 12 contacts the abutting surface 44 of the slider 42 and is pressed. A force for pulling the spring 45 in the Ts direction, such as a state holding force, is applied to the first latch 60.

  On the other hand, when moving in the Ts direction, a force that is larger than the force that moves the coating unit 15 when the latch pin 12 is pulled in contact with the holding surface 62 (the force that pulls the coating unit without leaving the slider) is applied. The spring 45 is applied to the first latch 60 as a pulling force in the Ts direction.

  Therefore, the latch pin 12 is sandwiched between the first latch 60 so as to be in contact with both the holding surface 62 and the abutting surface 44 of the slider 42 without any gap even when moving or changing direction. Therefore, smooth switching can be performed without causing a gap in the sandwiched portion. Therefore, since the moving force by the slider 42 is always transmitted to the coating unit 15 and does not stay there, the wear of the coating roller 338 does not partially progress.

  Therefore, even if the latch pin 12 is thin by the above-described latch mechanism 31 and a gap is generated due to the fitting between the pin 63 and the second latch 64, the application unit 15 is always moved even during movement and when switching the movement direction. The latch pin 12 can be clamped without a gap. Therefore, the holding state (clamping state) does not change, and smooth movement is possible. Since the moving force by the slider 42 is always transmitted to the application unit 15 and does not stay there, the application unit 15 can move smoothly and the wear of the application roller 338 does not partially progress. That is, by using this configuration, partial wear of the coating rollers 348 and 349 is suppressed by reliably holding the coating unit 15 including the coating rollers 338 and 348 when moving and switching the moving direction. can do.

  As described above, the pulling force Ts (for example, 60 N) of the spring 45 in the pulling direction is designed to be larger than the load Tp (for example, 30 N). Therefore, even when the coating unit 15 is mounted and connected, it can be pulled back to the normal position (on the abutting surface 44) even if the latch pin 12 rebounds on the abutting surface 44 of the slider 42 when it is connected. . Alternatively, even when the pushing force when the coating unit 15 is inserted is weak and the latch pin 12 does not reach the abutting surface 44 of the slider 42, the coating unit 15 is moved into the coating device 33 by pulling the latch pin 12 with the spring 45. You can pull in.

  Therefore, in the embodiment of the present invention, the application unit 15 including the application rollers 338 and 348 is reliably held by the latch mechanism 31 even when the application unit is mounted (connected) out of the normal position. Thus, partial wear of the application rollers 338 and 348 can be suppressed.

(Comparative example)
FIG. 8A to FIG. 8D are top views showing the configuration of the moving mechanism 59 in the comparative example. The moving mechanism 59 includes a frame 50 fixed to the housing of the apparatus and a slider 52 that swings in the width direction of the recording medium W during printing (a direction orthogonal to the conveyance direction of the recording medium W) by the motor 41. Yes. The slider 52 is connected to a rotatable screw shaft 56, and the slider 52 slides in the frame 50 when the screw shaft 56 receives power from the motor 41 and rotates. A latch 53 that rotates about the rotation center A is mounted on the slider 52, and its position is defined by, for example, ON / OFF of a solenoid 54.

  When the application unit 15 (see FIG. 3) is outside the apparatus, the latch 53 is in the retracted position Poff, and when inserted, the latch pin 12 fixed to the application unit 15 is pushed in until it hits the slider 52 (FIG. 8A). ). Thereafter, the latch 53 is rotated to the position Pon by the solenoid 54 and hooked on the latch pin 12, whereby the holding of the coating unit 15 is completed (FIG. 8B).

  In the configuration of the comparative example described above, there is a possibility that the latch 53 may not be hooked, for example, when the coating unit 15 is inserted vigorously and the coating unit is displaced from the normal position. When the coating unit is pushed, the abutting surface 55 of the slider 52 and the latch pin 12 are in contact with each other, and when the coating unit 15 is pulled, the latch 53 and the latch pin 12 are in contact with each other. However, as a measure for improving the likelihood of the latch that can deal with a wider range of the thickness of the latch pin 12, there is a case where the gap between the latch 53 and the abutting surface 55 of the slider 52 is increased in order to increase the play in the fitting state. is there.

  For example, when there is play in this comparative example, when a moving force is applied in the Tp direction, the latch pin 12 is pushed in contact with the slider 52 as shown in FIG. Communicated. When a moving force is applied in the Ts direction, the moving force of the moving mechanism 59 is transmitted by the latch pin 12 being pulled in contact with the latch 53 as shown in FIG.

  Therefore, at the switching point of the movement direction when the coating unit 15 is moved, the gap D is set for a period during which the fitting state is switched from FIG. 8C to FIG. 8D or from FIG. 8D to FIG. During the period until absorption, the latch pin 12 does not come into contact with the slider 52 or the latch 53. Therefore, the moving force by the slider 52 is not transmitted and the application unit 15 stays in place, and the wear of the application roller 338 proceeds only at this position.

  On the other hand, in the configuration of the moving mechanism according to the present invention, as described above, the tensile force in the Ts direction of the spring 45 of the first latch 60 is larger than the load accompanying the conversion and stop of the moving direction. Designed. Therefore, regardless of the direction of movement or the case of switching the movement direction, the latch pin 12 of the coating unit is always held between the first latch 60 and the second latch 64 without any gap. Therefore, there is no problem as in the comparative example.

  In some embodiments, the pretreatment liquid coating unit 330 may be referred to as a coating device, or the pretreatment coating / drying device 110 may be referred to as a coating device.

  In the above embodiment, the coating apparatuses (coating mechanisms) 33 and 34 have been described with respect to the application of the pretreatment liquid before the ink adheres. However, the above-described coating apparatus can be used to apply the posttreatment liquid after image formation. May be used. Even in this case, by using the latch mechanism as described above, the partial wear of the post-processing liquid application roller can be suppressed by reliably holding the application unit including the post-processing liquid application.

  As mentioned above, although this invention has been demonstrated based on each embodiment, this invention is not limited to the requirements shown in the said embodiment. With respect to these points, the gist of the present invention can be changed without departing from the scope of the present invention, and can be appropriately determined according to the application form.

10 Housing 10o Opening 11 Wheel 12 Latch Pin (Fitting Member)
13 Position sensor 14 Pressure unit 15 Application unit (treatment liquid container)
16 Positioning pin 17 Positioning plate 28 Position detection target 30 Moving mechanism 31 Latch mechanism 33, 34 Coating mechanism (back surface coating unit, surface coating unit, coating device)
40 Frame 41 Motor 42 Slider (moving member)
43 Screw shaft
44 Abutting surface (contact surface)
45 Spring (elastic body)
60 First latch 61 Guide surface 62 Holding surface 63 Pin 64 Second latch 81 Application control unit 82 Swing control unit 100 Paper feed device 101 Pretreatment coating and drying device (pretreatment device)
102 First inkjet printer 330 Pretreatment liquid application unit 331 Infeed roller (conveying means)
332 Feed nip roller (conveying means)
337 Squeeze rollers 338, 348 Application rollers 339, 349 Pressure roller 340 Pretreatment liquid supply unit 1000 Image forming system W Recording medium L Pretreatment liquid (treatment liquid)

JP 2013-091262 A

Claims (8)

An application unit having an application roller for applying a treatment liquid to a recording medium being conveyed;
A pressure roller for sandwiching the recording medium with the application roller;
A moving mechanism that moves the coating unit in a direction orthogonal to the conveyance direction of the recording medium ,
The moving mechanism includes a first latch that holds the coating unit in a connectable manner and a second latch that holds the first latch;
The coating unit is detachable from the coating device.
Coating device. The coating unit has a fitting member that fits with the first latch,
The moving mechanism has a moving member including a contact surface that moves together with the application unit and contacts the fitting member,
The first latch includes a bifurcated clip portion having a holding surface formed on the inside thereof,
The fitting member, said is sandwiched between the contact surface and the holding surface of the pinching portion of said first latch of the moving member, the coating apparatus according to claim 1. Even when the moving direction of the moving mechanism is switched, the holding state in which the fitting member is held between the contact surface of the moving member and the holding surface of the holding portion of the first latch does not change. The coating device according to claim 2 . A guide surface for guiding the connection of the coating unit to the moving mechanism while contacting the fitting member when the coating unit is mounted is further formed inside the pinching portion of the first latch. The coating apparatus according to claim 2 or 3 . The first latch has an elastic body that applies a force in a direction of sandwiching the fitting member of the coating unit and a direction of releasing the fitting member,
The elastic body applies a force in a direction of sandwiching the fitting member of the application unit when the application unit is connected and in a connected state,
The coating apparatus according to claim 4 , wherein the coating apparatus is switched so as to apply a force in a direction in which the fitting member of the coating unit is released when the coating unit is separated and in a separated state. The coating apparatus according to claim 5 , wherein a force for clamping the fitting member applied to the coating unit by the first latch is greater than a load received by the first latch while the coating unit is moving. The second latch holds the first latch at a predetermined position by holding an end portion of the guide surface of the first latch in a state where the coating unit is connected to the moving mechanism. The coating device according to claim 4 . Conveying means for conveying the recording medium;
A recording apparatus for ejecting and adhering ink to the recording medium;
A coating device positioned upstream in the conveyance direction of the recording medium of the recording device,
The coating device includes:
An application unit having an application roller for applying a treatment liquid to the recording medium;
A pressure roller that sandwiches the recording medium with the coating roller; and a moving mechanism that moves the coating unit in a direction perpendicular to the conveyance direction of the recording medium ;
The moving mechanism includes a first latch that holds the coating unit in a connectable manner and a second latch that holds the first latch;
The coating unit is detachable from the coating device.
Image forming system.

Images