JP7263802B2 - CONVEYING APPARATUS, IMAGE PROCESSING APPARATUS, AND IMAGE FORMING APPARATUS - Google Patents

Description

The present invention relates to a conveying device, an image processing device, and an image forming device.

Conventionally, a recording unit that ejects ink to record an image on a sheet, or a reading unit that reads an image recorded on a sheet and generates image data (hereinafter, the recording unit and reading unit are collectively referred to as “image processing ) is known.

In such an image processing apparatus, it is important to stabilize the distance between the sheet and the image processing section in order to maintain the quality of image processing. However, the sheet may flutter due to vibrations generated by a motor or the like included in the image processing apparatus, and the distance between the sheet and the image processing unit may vary.

On the other hand, in a printing apparatus that records an image on a printing paper on a platen roller with a print head, there has been conventionally known a technique for supplying an air flow to the printing paper from an air nozzle provided on the opposite side of the print head (for example, , see Patent Document 1).

According to the technique described in Patent Document 1, an air layer is formed between the sheet and the hardware that supports the sheet (for example, the platen roller of Patent Document 1), thereby preventing vibration from a motor or the like from being transmitted to the sheet. can be prevented. However, in reality, it is difficult to suppress the fluttering of the seat simply by blowing an air flow onto the seat. There are various possible causes for the sheet to flutter due to the supply of airflow, but one of the causes is, for example, turbulent flow between the sheet and the surrounding hardware.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a technique for stabilizing the distance between an image processing section and a medium to be conveyed in a conveying device that conveys a medium to be conveyed toward an image processing section.

In order to solve the above technical problem, one aspect of the present invention is a conveying device that conveys a medium to be conveyed so that an image processing section performs image processing, the conveying path passing through a position facing the image processing section. a transport unit for transporting the transport medium along the transport path; a guide member disposed on the opposite side of the transport path from the image processing unit for guiding the transport medium along the transport path; a blowing portion for blowing air toward between the medium to be conveyed and the guide member; and a suction portion, wherein the blowout portion has a plurality of blowout ports spaced apart in a width direction of the conveyed medium intersecting the conveying direction of the conveyed medium, each blowing out air, the blowout portion is divided into a central region in the width direction and end regions located on both sides of the central region, the outlets arranged in the end regions are inclined toward the center in the width direction, The suction portion has a plurality of suction ports spaced apart in the width direction, each of which sucks air, and when the suction portion is divided into the central region and the end regions, The suction ports arranged in the region are characterized by having a larger opening area than the suction ports in the end region .

According to the present invention, since the thickness of the air layer between the medium to be conveyed and the guide member can be stabilized, variations in the distance between the image processing section and the medium to be conveyed can be reduced, and the quality of image processing can be lowered. can be suppressed.

1 is a diagram showing the configuration of an inkjet printer according to this embodiment; FIG. FIG. 2 is a hardware configuration diagram of an inkjet printer according to the embodiment; FIG. 2 is a schematic diagram showing the internal structure of an inkjet printer; Enlarged view around the guide roller. Sectional drawing in VV of FIG. The figure which shows the example of a blow-off speed table. 4 is a flowchart of image recording processing;

[Summary of the present invention]

In order to form an air layer with a stable thickness between the medium to be conveyed and the guide member, which is guided by the guide member and moves on the conveying path, the conveying apparatus according to the present invention has an air layer between the medium to be conveyed and the guide member. One of the gists is to provide a blowing portion for blowing air toward the medium and a suction portion for sucking the air passing between the conveying medium and the guide member. As a result, the distance between the medium to be conveyed and the image processing section is stabilized, so that deterioration in quality of image processing caused by fluttering of the medium to be conveyed can be suppressed.

[Embodiment of the present invention]
An inkjet printer 100, which is an example of an image processing apparatus and an image forming apparatus, will be described below with reference to FIGS. 1 to 4. FIG. FIG. 1 is a diagram showing the configuration of an inkjet printer 100 according to this embodiment. FIG. 2 is a hardware configuration diagram of the inkjet printer 100. As shown in FIG. FIG. 3 is a schematic diagram showing the internal structure of the inkjet printer 100. As shown in FIG. FIG. 4 is an enlarged view of the periphery of the guide roller 213. As shown in FIG.

As shown in FIG. 1 , the inkjet printer 100 includes a loading section 11 , a preprocessing section 21 , a preprocessing drying section 31 , an image forming section 41 , a postprocessing section 51 , a postprocessing drying section 61 , and an unloading section 71 . include.

The loading unit 11 is a mechanism for transporting the medium 10 to the preprocessing unit 21 and includes a paper feed roller 15 and transport rollers 16 . The medium 10 according to this embodiment is continuous paper (roll paper), and the medium 10 is wound around a paper feed roller 15 . By rotating the paper supply roller 15 and the transport roller 16 , the medium 10 is fed from the paper supply roller 15 and transported to the preprocessing section 21 .

The pretreatment unit 21 is a mechanism that applies pretreatment to the surface of the loaded medium 10 . The pretreatment is, for example, a process of applying a pretreatment liquid having an action of aggregating liquid (ink) to the printing surface of the medium 10 . The pretreatment liquid is, for example, a solution containing a water-soluble aliphatic organic acid.

The pretreatment drying section 31 is a mechanism for drying the pretreated medium 10 and includes a heat roller 35 . The heat roller 35 is heated to about 50.degree. C. to 100.degree.

The image forming unit 41 is a mechanism that ejects liquid (ink) onto the medium 10 . The image forming unit 41 performs an image forming process of ejecting liquid onto the medium 10 in order to form a desired image, and an image forming process to maintain the performance of the liquid ejecting unit (nozzle of an inkjet head, etc.). Flushing is performed to eject non-contributing liquid onto the medium 10 .

The post-processing unit 51 is a mechanism that performs post-processing on the surface of the medium 10 onto which the liquid has been ejected. The post-treatment is, for example, a process of ejecting a post-treatment liquid onto the medium 10 in the form of spots.

The post-processing drying section 61 is a mechanism for drying the post-processed medium 10 , and includes the heat roller 35 like the pre-processing drying section 31 . The action of the heat roller 35 evaporates water in the post-treatment liquid discharged onto the medium 10 .

The carry-out section 71 is a mechanism for winding the medium 10 carried out from the post-processing drying section 61 , and includes a paper discharge roller 75 and a transport roller 76 . By rotating the discharge roller 75 and the transport roller 76 , the medium 10 that has undergone all the processes described above is wound around the discharge roller 75 .

The above configuration is an example, and the configuration of the inkjet printer 100 is not limited to the above. For example, in the above description, a roll of continuous paper is shown as the medium 10, but the type of the medium 10 is not limited to this, and may be, for example, a continuous form, cut paper, or the like. Also, depending on the type of medium 10, the type of liquid, etc., one or more of the pre-processing section 21, the pre-processing drying section 31, the post-processing section 51, and the post-processing drying section 61 are not included. It may be a configuration.

As shown in FIG. 2, the inkjet printer 100 includes a CPU (Central Processing Unit) 110, a RAM (Random Access Memory) 120, a ROM (Read Only Memory) 130, a HDD (Hard Disk Drive) 140, an operation panel 150, and an I /F 160 are connected via a common bus 180 .

The CPU 110 is a computing means and a controller that controls the overall operation of the inkjet printer 100 . The RAM 120 is a volatile storage medium from which information can be read and written at high speed, and is used as a working area when the CPU 110 processes information. The ROM 130 is a read-only non-volatile storage medium and stores programs such as firmware. The HDD 140 is a non-volatile storage medium capable of reading and writing information and having a large storage capacity, and stores an OS (Operating System), various control programs, application programs, and the like.

The inkjet printer 100 processes a control program stored in the ROM 130 , an information processing program (application program) loaded from a storage medium such as the HDD 140 to the RAM 120 , and the like using the computing function of the CPU 110 . A software control unit including various functional modules of the inkjet printer 100 is configured by the processing. A combination of the software control section configured in this way and the hardware resources installed in the inkjet printer 100 configures functional blocks that implement the functions of the inkjet printer 100 .

The operation panel 150 is a user interface including a display for displaying a screen, a touch panel superimposed on the display, push buttons, and the like. The touch panel and push buttons are an example of an operation unit that receives an operator's operation for inputting various types of information, which will be described later. The I/F 160 is an interface that connects the conveying unit 210 , the recording unit 220 , the blowing unit 230 , the suction unit 240 , and the laser displacement meters 251 , 252 , 253 and 254 to the common bus 180 . 1, and the recording unit 220 corresponds to the image forming unit 141 in FIG.

As shown in FIG. 3, the inkjet printer 100 has a printer function that causes the conveying unit 210 to convey the continuous sheet S along the conveying path P and causes the recording unit 220 to record an image on the continuous sheet S. FIG. However, a specific example of the image processing apparatus is not limited to the inkjet printer 100, and may be a single-function scanner function, or a multifunction machine having a printer function and a scanner function.

The continuous sheet S is an example of a transport medium transported by the transport unit 210, and corresponds to the medium 10 in FIG. The continuous sheet S is a long belt-shaped sheet, and after an image is recorded by the recording unit 220, it is cut into a predetermined length. However, a specific example of the medium to be conveyed is not limited to the continuous form sheet S, and for example, cut paper cut in advance to a predetermined size (for example, A4, B5, etc.) may be used.

The transport path P is an internal space of the inkjet printer 100 through which the continuous sheet S can pass, and faces recording heads 221, 222, 223, 224, 225, and 226, which will be described later. pass through the position. More specifically, the transport path P refers to the space between the recording heads 221 to 226 and guide rollers 213, 214, 215 and 216, which will be described later. Although FIG. 2 shows the arc-shaped transport path P, the shape of the transport path P is not limited to this, and may be linear, for example.

The conveying unit 210 includes, for example, conveying rollers 211 and 212 that convey the continuous sheet S in the conveying direction (leftward direction in FIG. 3). The transport roller 211 is arranged on the upstream side of the transport path P from the recording unit 220 . The conveying roller 211 is rotated by a driving force of a conveying motor (not shown), and feeds the pre-wound continuous sheet S to the conveying path P. As shown in FIG. The transport roller 212 is arranged on the downstream side of the transport path P from the recording unit 220 . The conveying roller 212 is rotated by the driving force of a conveying motor (not shown), and winds up the continuous sheet S on which the image is recorded by the recording unit 220 .

Guide rollers 213 , 214 , 215 and 216 are arranged between the transport rollers 211 and 212 . The guide rollers 213 to 216 are arranged on the opposite side of the recording section 220 with the transport path P interposed therebetween. The guide rollers 213 to 216 are examples of guide members that guide the continuous sheet S along the transport path P. As shown in FIG.

Further, the guide rollers 213 to 216 are idle rollers that are rotated in contact with the continuous sheet S conveyed on the conveying path P. As shown in FIG. That is, the driving force of the transport motor is not transmitted to the guide rollers 213-216. However, vibrations generated when the transport motor is driven are transmitted to the guide rollers 213 to 216 through the housing, frame, etc. that support the components of the inkjet printer 100 .

A specific example of the guide member is not limited to the guide rollers 213 to 216, and may be a platen or the like that supports the continuous sheet S at a position facing the recording heads 221 to 226, for example. That is, the guide member does not necessarily have to rotate.

The recording unit 220 is an example of an image processing unit that records an image on the continuous sheet S by ejecting ink toward the continuous sheet S conveyed on the conveying path P. FIG. However, a specific example of the image processing unit is not limited to the recording unit 220, and may be, for example, a reading unit (scanner) that reads an image recorded on the continuous sheet S and generates image data. The recording unit 220 includes a plurality of recording heads 221, 222, 223, 224, 225, and 226 that eject ink of different colors.

The recording heads 221 to 226 are, for example, full-line type recording heads provided with ink ejection holes (not shown) throughout the width direction of the continuous sheet S that intersects (perpendicularly) with the conveying direction. However, specific examples of the recording heads 221 to 226 are not limited to this, and for example, they may be of a carriage type in which a carriage having ink ejection holes formed therein ejects ink while moving in the width direction (main scanning direction). Further, the specific principle by which the recording heads 221 to 226 eject ink is not particularly limited. For example, ink may be ejected from the nozzles by vibrating piezoelectric elements due to drive voltage applied from the CPU 110 .

In this embodiment, the print head 221 prints black (Bk) ink, the print head 222 prints cyan (C) ink, the print head 223 prints magenta (M) ink, and the print head 224 prints yellow (Y) ink. The head 225 ejects light cyan (LC) ink, and the recording head 226 ejects light magenta (LM) ink. However, the number and combination of colors ejected by the recording unit 220 are not limited to the above example.

In this embodiment, the print heads 221, 222, 223, 224, 225, and 226 are arranged in this order from upstream to downstream in the transport direction. A guide roller 213 is arranged between the conveying roller 211 and the recording head 221, a guide roller 214 is arranged between the recording heads 222 and 223, a guide roller 215 is arranged between the recording heads 224 and 225, A guide roller 216 is arranged between the recording head 226 and the conveying roller 212 . However, the positional relationship between the guide rollers 213-216 and the recording heads 221-226 is not limited to the above example.

As shown in FIGS. 3 and 4 , the blowout section 230 includes blowout nozzles 231 , 232 , 233 and 234 and an air pump 235 . The air pump 235 is connected through an air passage 236 to each of the blowout nozzles 231-234. Air pump 235 compresses air under the control of CPU 110 to generate positive pressure in air passage 236 . In other words, the air pump 235 supplies air at a predetermined wind speed to the blowout nozzles 231 to 234 through the air passage 236 by driving current supplied from the CPU 110 .

Blow-out nozzles 231-234 are arranged adjacent to guide rollers 213-216, respectively. More specifically, the blow nozzles 231 to 234 are adjacent to the guide rollers 213 to 216 respectively on the upstream side of the continuous sheet S in the conveying direction. The blowing nozzles 231 to 234 blow air supplied from an air pump 235 toward between the continuous sheet S and the guide rollers 213 to 216 .

5 is a cross-sectional view taken along line VV of FIG. 4. FIG. Since the blow-out nozzles 231 to 234 have the same configuration, the blow-out nozzle 231 will be described in detail below.

As shown in FIG. 5, the blow nozzle 231 has a plurality of blow outlets 231a, 231b, 231c. The plurality of outlets 231a to 231c are spaced apart in the width direction of the continuous sheet S. As shown in FIG. Each of the plurality of blowout ports 231a to 231c blows out the air supplied from the air pump 235 through the air passage 236 toward the outside of the blowout nozzle 231. As shown in FIG.

Here, as shown in FIG. 5, in the width direction of the continuous sheet S, the blowing nozzles 231 are divided into a central region, a left end region positioned to the left of the central region, and a right end region positioned to the right of the central region. Consider the case where In this case, the air outlet 231a arranged in the central area blows air in a direction orthogonal to the width direction of the continuous sheet S. As shown in FIG. That is, in the width direction of the continuous sheet S, the partition wall defining each of the plurality of outlets 231a extends in a direction perpendicular to the width direction of the continuous sheet S. As shown in FIG.

On the other hand, the air outlet 231b arranged in the left end region is inclined to the right in the width direction of the continuous sheet S and blows air. In addition, the air outlet 231c arranged in the right end region is inclined to the left in the width direction of the continuous sheet S and blows out air. That is, in the width direction of the continuous sheet S, the partition walls defining the outlets 231b and 231c are inclined toward the center of the continuous sheet S with respect to the direction orthogonal to the width direction of the continuous sheet S. . The left end region and the right end region are end regions located on both sides of the central region.

The width of the entire blowing nozzle 231 is larger than the width of the continuous sheet S. Also, the ratio of the central area, the left end area, and the right end area to the entire blowout nozzle 231 is not particularly limited, but is, for example, 80%:10%:10% to 90%:5%:5%. Furthermore, the inclination angle of the outlets 231b and 231c is not particularly limited, but is, for example, 5° to 30°, more preferably 10° to 15°.

Returning to FIGS. 3 and 4 , the suction section 240 includes suction nozzles 241 , 242 , 243 and 244 and an air pump 245 . An air pump 245 is connected to each of the suction nozzles 241 to 244 through an air passage 246 . Air pump 245 compresses air under the control of CPU 110 to generate negative pressure in air passage 246 . In other words, the air pump 245 sucks air from the suction nozzles 241 to 244 through the air passage 246 by driving current supplied from the CPU 110 .

The suction nozzles 241-244 are arranged adjacent to the guide rollers 213-216, respectively. More specifically, the suction nozzles 241 to 244 are adjacent to the guide rollers 213 to 216 respectively on the downstream side of the continuous sheet S in the conveying direction. The suction nozzles 241 to 244 suck the air passing between the continuous sheet S and the guide rollers 213 to 216 and discharge it to the air pump 245 .

Although not shown, the suction nozzles 241 to 244 may have a plurality of suction ports (not shown) spaced apart in the width direction of the continuous sheet S, like the blowing nozzle 231 shown in FIG. . Further, when the outlets 231b and 231c are inclined as shown in FIG. 5, the suction ports in the central region may have a larger opening area than the suction ports in the end regions. As another example, the suction nozzles 241 to 244 may have slits (not shown) continuous in the width direction of the continuous sheet S instead of the plurality of suction ports.

That is, in the conveying direction of the continuous sheet S, the blow nozzle 231 and the suction nozzle 241 are arranged on opposite sides of the guide roller 213 . Further, it is desirable that the blowout nozzle 231 and the suction nozzle 241 are arranged so that the blowout ports 231 a to 231 c and the suction ports face the contact point between the continuous sheet S and the guide roller 213 . The same applies to the other blowout nozzles 232-234 and the other suction nozzles 242-244.

Furthermore, laser displacement meters 251, 252, 253, and 254 are arranged on the side opposite to the guide rollers 213 to 216 with the continuous sheet S interposed therebetween. Note that the laser displacement meters 251-254 may be provided at the positions of all the guide rollers 213-216, or may be provided at only some of the plurality of guide rollers 213-216.

As shown in FIG. 4, the laser displacement gauge 251 detects the thickness of the air layer (that is, the size of the gap) _t1 between the continuous sheet S and the guide roller 213, and outputs the detection result to the CPU 110. It is an example of an air layer detection sensor. Although the method for detecting the thickness _t1 of the air layer by the laser displacement gauges 251 to 254 is not particularly limited, the following method is conceivable, for example. Since the configurations of the laser displacement gauges 251 to 254 are the same, the laser displacement gauge 251 will be described in detail below.

The laser displacement meter 251 is composed of, for example, an LED (not shown) that outputs a laser beam toward the continuous sheet S and a photodiode that receives the laser beam reflected by the continuous sheet S. Then, the laser displacement meter 251 measures the time from when the LED is made to output the laser beam to when the photodiode receives the laser beam. Next, the laser displacement gauge 251 calculates the distance _t2 between the laser displacement gauge 251 and the continuous sheet S based on the measured time and the speed of light. Then, the laser displacement gauge 251 subtracts the calculated distance _t2 from the known distance t between the guide roller 213 and the laser displacement gauge 251 to calculate the thickness _t1 of the air layer. Note that the above-described time measurement and distance calculation may be executed by the CPU 110 .

Further, the controller may set the average value of the detection values of the laser displacement gauges 251 to 254 as the thickness t ₁ of the air layer. Further, the controller may set the average value of a plurality of detection values repeatedly detected at predetermined time intervals (eg, 10 [msec]) by the laser displacement gauges 251 to 254 as the thickness t ₁ of the air layer.

FIG. 6 is a diagram showing an example of a blowing speed table stored in RAM 120, ROM 130, or HDD 140. As shown in FIG. The blowing speed table includes the sheet thickness of the continuous form sheet S, the conveying speed of the continuous sheet S by the conveying unit 210 (the rotation speed of the conveying rollers 211 and 212), and the blowing speed V of the air blown from the blowing unit 230. is a two-dimensional matrix showing the relationship between The set values of the blowing speed table are set in advance based on the results of experiments and simulations. Further, the relationship between paper thickness, transport speed, and blowing speed V is not limited to the form of a table, and may be stored in the form of a function in which the blowing speed V is output when the paper thickness and conveying speed are input.

The blowing speed V increases as the paper thickness increases. That is, _V11 < _V21 < _V31 < _V41 , _V12 < _V22 < _V32 < _V42 , and _V13 < _V23 < _V33 < _V43 . Also, the blowing speed V increases as the transport speed increases. That is, _V11 < _V12 < _V13 , _V21 < _V22 < _V23 , _V31 < _V32 < _V33 , and _V41 < _V42 < _V43 . Also, the absolute values of the blowing velocities V ₁₁ to V ₄₃ are appropriately set within a range of, for example, 5 to 70 [m/sec], more preferably 10 to 50 [m/sec].

Also, instead of the blowing speed V, the blowing speed table may include a drive current I to be supplied to the air pump 235 to blow air at the blowing speed V. FIG. The drive current I increases as the paper thickness increases. That is, _I11 < _I21 < _I31 < _I41 , _I12 < _I22 < _I32 < _I42 , and _I13 < _I23 < _I33 < _I43 . Further, the drive current I increases as the transport speed increases. That is, _I11 < _I12 < _I13 , _I21 < _I22 < _I23 , _I31 < _I32 < _I33 , and _I41 < _I42 < _I43 . Absolute values of the drive currents I ₁₁ to I ₄₃ are appropriately set according to the specifications of the air pump 235 .

The RAM 120, ROM 130, or HDD 140 stores a predetermined target value _tTgt , upper limit value _tH , and lower limit value _tL . The target value _tTgt is a control target value for the thickness _t1 of the air layer between the continuous sheet S and the guide roller 213 . The upper limit value _tH is the upper limit value of the allowable range of the thickness _t1 of the air layer. The lower limit value _tL is the lower limit value of the allowable range of the thickness _t1 of the air layer. The tolerance includes the target value t _Tgt . That is, _tL < _tTgt < _tH . A specific example of each value varies depending on the specifications of the inkjet printer 100, but for example, the target value t _Tgt is 1.0 [mm], the allowable range is 0.5 to 1.5 [mm], and more preferably 0.8 ~1.2 [mm].

Next, image recording processing executed by the inkjet printer 100 will be described with reference to FIG. FIG. 7 is a flowchart of image recording processing.

The controller of the inkjet printer 100 accepts an operator's operation of inputting the sheet thickness and transport speed of the continuous sheet S through the operation panel 150 (S11). Next, the controller determines blowing speed V (or driving current I) corresponding to the paper thickness and transport speed input in step S11 based on the blowing speed table (S12). That is, the controller reads the blowing speed V corresponding to the input paper thickness and conveying speed from the blowing speed table.

As an example, in step S11, the controller selects one of multiple paper thickness candidates (eg, 64, 128, 250, 300, etc.) and multiple transport speed candidates (eg, 30, 75, 150, etc.). ) may be selected by the operator. As another example, the controller may cause the operator to select one of the candidates for the paper type of the continuous form sheet S (for example, plain paper, glossy paper, etc.) to obtain the paper thickness corresponding to the selected paper type. Similarly, the controller causes the operator to select one of the image recording quality candidates (e.g., photo printing, document printing, draft printing, etc.) and obtains the transport speed corresponding to the selected image recording quality. good too.

Next, the controller causes the blowing nozzles 231 to 234 to start blowing air at the blowing speed V determined in step S12 (S13). That is, the controller supplies the air pump 235 with the driving current I corresponding to the determined blowing speed V. FIG. After that, the controller continues to supply the drive current I to the air pumps 235 and 245 until one of steps S15, S21, and S22 is executed.

The air suction speed of the suction nozzles 241-244 may be the same as the blowing speed V of the blowing nozzles 231-234. In this case, the controller should supply the driving current I corresponding to the determined blowing speed V to both the air pumps 235 and 245 in step S13.

Next, the controller determines whether the thickness _t1 of the air layer detected by the laser displacement gauges 251-254 is within the allowable range (S14). That is, the controller detects the thickness t ₁ of the air layer by the laser displacement gauges 251 to 254 and compares the detected thickness t ₁ of the air layer with the upper limit value t _H and the lower limit value t _L . Note that the controller may wait from the time the air pumps 235 and 245 are driven until the wind speed of the air blown from the blowing nozzles 231 to 234 stabilizes before executing step S14.

Next, when the controller determines that the detected thickness _t1 of the air layer is outside the allowable range (S14: No), the controller stops the air pumps 235 and 245 and notifies an error through the operation panel 150 ( S15). Then, the controller returns to step S11 and continues the process.

The content of the error in step S15 is not particularly limited, but it may be, for example, that there is an error in the value input in step S11. The notification method is not particularly limited, but for example, displaying a message on a display, lighting an LED lamp (not shown), outputting a guide voice from a speaker (not shown), etc. can be considered. The method of notification in steps S21 and S22, which will be described later, is the same.

On the other hand, when the controller determines that the detected thickness _t1 of the air layer is within the allowable range (S14: Yes), it starts image recording on the continuous sheet S (S16). That is, the controller drives the transport motor at a speed corresponding to the transport speed input in step S11 to transport the continuous sheet S to the transport unit 210 . Further, the controller applies a driving voltage to the piezoelectric element at a predetermined timing to cause the recording section 220 to eject ink.

Next, the controller repeatedly executes the processes of steps S17 to S20 until the image recording is completed (S21, S22). First, the controller determines whether or not the thickness t ₁ of the air layer newly detected by the laser displacement gauges 251 to 254 is within the allowable range (S17). The processing of step S17 is the same as that of step S14. However, the thickness _t1 of the air layer is a value newly detected in step S17. Also, the thickness _t1 of the air layer is newly detected each time step S17 is executed.

Next, when the controller determines that the detected air layer thickness t ₁ is within the allowable range (S17: Yes), the controller compares the air layer thickness t ₁ with the target value t _Tgt ( S18). In step S18, the thickness _t1 of the air layer detected in the most recent step S17 may be used. Next, when the controller determines that the thickness _t1 of the air layer matches the target value _tTgt (S18: Yes), it determines whether or not all images have been recorded on the continuous sheet S (S19 ). When the controller determines that all the images have not been recorded on the continuous sheet S (S19: No), the controller returns to S17 and continues the process.

On the other hand, when the controller determines that the air layer thickness t ₁ is within the allowable range and does not match the target value t _Tgt (S17: Yes & S18: No), the air layer thickness t ₁ is the target value t _Tgt (S20). In other words, the controller increases or decreases the drive current I supplied to the air pumps 235, 245 so that the thickness _t1 of the air layer approaches the target value _tTgt .

Specifically, when the thickness t ₁ of the air layer is greater than the target value t _Tgt (t ₁ >t _Tgt ), the controller slows down the blowing speed V (decreases the driving current I). On the other hand, when the thickness t ₁ of the air layer is smaller than the target value t _Tgt (t ₁ <t _Tgt ), the controller increases the blowing speed V (increases the drive current I). Furthermore, the controller should increase the amount of change in the blowing speed V (drive current I) as the difference between the thickness _t1 of the air layer and the target value _tTgt increases.

Further, when the controller determines that the thickness _t1 of the air layer newly detected in step S17 is outside the allowable range (S17: No), the controller abnormally terminates image recording (S21). That is, the controller stops the transport section 210, the recording section 220, and the air pumps 235 and 245, and notifies through the operation panel 150 that the image recording process has ended abnormally (S21).

Further, when the controller determines that all images have been recorded on the continuous sheet S without the thickness _t1 of the air layer falling outside the allowable range (S19: Yes), the controller normally ends the image recording (S22 ). That is, the controller stops the transport section 210, the recording section 220, and the air pumps 235 and 245. FIG. Also, the controller may inform through the operation panel 150 that the image recording process has been normally completed.

Note that in steps S21 and S22, different operations may be performed in addition to the content of the notification. As an example, the controller may not delete the image data to be recorded from the RAM 120 or HDD 140 in step S21, and may delete the image data in step S22. As another example, the controller may change the discharge destination of the image-recorded continuous sheet S wound around the conveying roller 212 in step S21 and step S22.

According to the above embodiment, for example, the following effects can be obtained.

First, consider the case where the suction nozzles 241 to 244 in FIG. 3 are omitted. In this case, the air blown from the blowing nozzles 231-234 is accelerated between the continuous sheet S and the guide rollers 213-216, and decelerated after passing through the continuous sheet S and the guide rollers 213-216. Therefore, on the downstream side of the guide rollers 213 to 216 in the conveying direction, it is considered that the air remaining between the continuous form sheet S and the guide rollers 213 to 216 swirls to generate a turbulent flow. This turbulence causes the continuous sheet S to flutter.

Therefore, as in the above embodiment, on both sides of the guide rollers 213 to 216, the air is blown out by the blowing part 230 and the air is sucked by the suction part 240, thereby reducing the flow of air around the guide rollers 213 to 216. be smooth. As a result, the thickness _t1 of the air layer between the continuous sheet S and the guide rollers 213 to 216 is stabilized, and the distance between the continuous sheet S and the recording heads 221 to 226 is kept constant. Therefore, deterioration in image recording quality is suppressed.

Further, as in the above-described embodiment, the continuous sheet S can be further suppressed from fluttering by directing the flow of air formed by the blowing section 230 and the suction section 240 along the conveying direction of the continuous sheet S. can be done. However, the arrangement of the blow nozzles 231 to 234 and the suction nozzles 241 to 244 is not limited to the examples shown in FIGS.

In addition, as in the above embodiment, the air supplied from the air pump 235 is rectified by providing the plurality of blowout ports 231a to 231c in the blowout nozzle 231 . As a result, the fluttering of the continuous sheet S is suppressed, and the image recording quality is further stabilized.

Furthermore, as in the above-described embodiment, the outlets 231b and 231c in the left end region and the right end region are inclined toward the center of the continuous sheet S. can be expected to have the effect of further stabilizing the thickness _t1 . As a result, deterioration in image recording quality in the central portion of the continuous sheet S, which is relatively conspicuous, can be suppressed intensively.

Further, as in the above embodiment, by determining the initial value of the blowing speed V according to the paper thickness and transport speed input by the operator, the time required for the air layer thickness _t1 to stabilize is shortened. can be made In addition, by repeatedly adjusting the blowing speed V during image recording so that the thickness _t1 of the air layer approaches the target value _tTgt , variations in image recording quality in one image recording process can be suppressed. can be done. On the other hand, if the thickness _t1 of the air layer is out of the allowable range, the image recording is terminated abnormally, thereby preventing wasteful consumption of the continuous sheet S and ink by continuing image recording with low image recording quality. can be prevented.

Note that the processing of step S11 in the image recording processing is not limited to the example of FIG. As another example, the controller may accept an operator's operation of inputting the blowing speed V through the operation panel 150 . Then, the controller may use the input blowing velocity V to execute the processes after step S13. As yet another example, the controller may allow the operator to select the paper thickness and transport speed in step S11, which is executed first. Then, the controller may allow the operator to select the blowing speed V in step S11 after executing step S15. Further, the controller may allow the operator to select the driving current I instead of the blowing speed V.

Further, the processing of step S14 in the image recording processing is not limited to the example of FIG. As another example, the controller may compare the air layer thickness t ₁ to a target value t _Tgt . Then, when the controller determines that the thickness _t1 of the air layer does not match the target value _tTgt (S14: No), the process may proceed to step S15. On the other hand, when the controller determines that the thickness _t1 of the air layer matches the target value _tTgt (S14: Yes), the process may proceed to step S16. Thus, image recording can be started after the ideal air layer thickness _t1 is reached.

Furthermore, the process of step S15 in the image recording process is not limited to the example of FIG. As another example, the controller may adjust the blowing speed V so that the thickness _t1 of the air layer approaches the target value _tTgt , as in step S20. In this case, the controller may return to step S14 to continue the process after executing step S15. In this way, by automatically bringing the thickness _t1 of the air layer closer to the target value _tTgt by feedback control, the operator's workload can be reduced.

In addition, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the technical scope of the present invention. All of are covered by the present invention. Although the above embodiment shows a preferred example, a person skilled in the art can realize various modifications from the disclosed contents. Such modifications are also included in the technical scope described in the claims.

REFERENCE SIGNS LIST 100 inkjet printer 10 medium 11 carry-in unit 15 paper feed roller 16 transport roller 21 pre-processing unit 31 pre-processing drying unit 35 heat roller 41 image forming unit 51 post-processing unit 61 post-processing drying unit 71 carry-out unit 75 paper discharge roller 76 Conveyance roller 110 CPU
120 RAMs
130 ROMs
140 HDDs
150 Operation panel 160 I/F
180 common bus 210 conveying unit 211, 212 conveying rollers 213, 214, 215, 216 guide roller 220 recording unit 221, 222, 223, 224, 225, 226 recording head 230 blowing unit 231, 232, 233, 234 blowing nozzle 231a, 231b, 231c Air outlet 235, 245 Air pump 240 Suction part 241, 242, 243, 244 Suction nozzle 251, 252, 253, 254 Laser displacement gauge

JP 2005-132064 A

Claims (10)

A conveying device for conveying a conveying medium for causing an image processing unit to perform image processing,
a transport unit that transports the transport medium along a transport path that passes through a position facing the image processing unit;
a guide member disposed on the opposite side of the image processing unit across the transport path and guiding the transport medium along the transport path;
a blowing portion for blowing air toward between the conveying medium and the guide member;
a suction unit arranged on the opposite side of the blowout unit with the guide member interposed therebetween and sucking air passing between the transport medium and the guide member;
The blowout section has a plurality of blowout openings that are spaced apart in a width direction of the conveying medium that intersects the conveying direction of the conveying medium, and each blows out air,
When the blow-out portion is divided into a central region in the width direction and end regions located on both sides of the central region, the blow-out ports arranged in the end regions are arranged on the center side in the width direction. tilted,
The suction part has a plurality of suction ports spaced apart in the width direction, each of which sucks air,
When the suction portion is divided into the central region and the end regions, the suction port arranged in the central region has a larger opening area than the suction port in the end region. Device. A conveying device for conveying a conveying medium for causing an image processing unit to perform image processing,
a transport unit that transports the transport medium along a transport path that passes through a position facing the image processing unit;
a guide member disposed on the opposite side of the image processing unit across the transport path and guiding the transport medium along the transport path;
a blowing portion for blowing air toward between the conveying medium and the guide member;
a suction unit arranged on the opposite side of the blowout unit with the guide member interposed therebetween and sucking air passing between the transport medium and the guide member;
The conveying device, wherein the guide member is a guide roller that rotates at a position separated by an air layer from the conveying medium conveyed on the conveying path . The blowout part is arranged upstream of the guide member in the transport direction of the transport medium,
3. The conveying apparatus according to claim 1 , wherein the suction unit is arranged downstream of the guide member in the conveying direction. an operation unit for receiving an operator's operation for inputting the thickness of the medium to be conveyed;
4. The controller according to any one of claims 1 to 3 , further comprising a controller that increases the velocity of the air blown out from the blowing part as the thickness of the conveyed medium input through the operation part increases. Conveyor. an operation unit that receives an operator's operation for inputting a transport speed of the transport medium;
5. The apparatus according to any one of claims 1 to 4 , further comprising a controller that increases the speed of the air blown out from the blowing portion as the transport speed of the medium input through the operation portion increases. Conveyor. an air layer detection sensor that detects the thickness of the air layer between the transport medium and the guide member;
6. The controller according to any one of claims 1 to 5 , further comprising a controller that adjusts the wind speed of the air blown out from the blowing part so that the thickness of the air layer detected by the air layer detection sensor approaches a target value. 1. The conveying device according to item 1. The controller determines that the thickness of the air layer detected by the air layer detection sensor is
Adjusting the wind speed of the air blown from the blowing part so that the thickness of the air layer approaches the target value when it is within the allowable range including the target value,
7. The conveying apparatus according to claim 6 , wherein the conveying unit is caused to stop conveying the conveying medium when it is out of the allowable range. A conveying device according to any one of claims 1 to 7 ;
An image processing apparatus, comprising: an image processing unit that performs image processing on the transport medium transported by the transport device. 3. The image processing section is a recording section that records an image on the conveying medium by ejecting ink, or a reading section that reads an image recorded on the conveying medium and generates image data. 9. The image processing device according to 8 . A conveying device according to any one of claims 1 to 7 ;
and an image forming unit that forms an image on the medium conveyed by the conveying device.

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