JP2007106511A - Conveyance device and recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conveyance device and a recording device capable of suppressing occurrence of flapping and levitation of a recording medium when conveying it due to shortage of suction force even under any environment and sucking and conveying the recording medium stably to form image having high quality. <P>SOLUTION: In this conveyance device having a conveyance carrying body for conveying the recording medium, a surface resistance value on a recording medium suction face side on the upstream side of the conveyance carrying body is controlled to 10<SP>12</SP>or less, moisture is uniformly supplied onto the whole face on the recording medium suction face side by application means based on the humidity detected by a humidity detection means for detecting humidity in the conveyance device, and a moisture supply means has a function for retreating from a recording medium conveyance roller. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transport apparatus that transports by adsorbing a recording medium to a transport carrier, and a recording apparatus having the transport apparatus.

  In general, an ink jet recording apparatus performs recording by ejecting ink from a recording head to a recording medium. The recording head can be easily made compact, can record high-definition images at high speed, and has a running cost. It is inexpensive and has a non-impact method, so that it has low noise, and it is easy to record a color image using multicolor inks.

  In particular, a full-line type recording apparatus having a line-type recording head in which a large number of ejection openings are arranged in the width direction of the recording medium can further increase the recording speed.

  However, in a full-line type recording apparatus, for example, in order to perform color recording, when a large number of line-type recording heads are arranged in the conveyance direction of the recording medium, the most upstream recording head is the most. The distance to the recording head at the downstream position is considerably long, which may cause the recording medium to rise in the recording area, which may cause disturbance of the recording image, jamming of the recording medium, and the like.

  Therefore, it is necessary to urge downward so that the recording medium does not float up.

  Specifically, a method is generally known in which an electrode is provided near a recording medium, an electric charge is applied to the electrode to generate an electrostatic force, and the recording medium is attracted by the electrostatic force to prevent lifting. .

  In a conventional ink jet recording apparatus, a recording medium fed by a paper feeding device is attracted and held on the upper surface of the transport belt by a suction force generator built in the transport carrier (transport belt) in a recording region. In general, a configuration in which the recording head is transported by a transport belt while recording is performed.

  Here, with reference to FIGS. 10 to 13, a conventional conveyor belt and a suction generator as disclosed in Patent Document 1 will be described.

  First, the configuration around the conveyor belt will be briefly described with reference to FIG. As shown in FIG. 10, the conveyance belt 131 of the conveyance unit 103 is an endless belt made of a synthetic resin such as polyethylene or polycarbonate having a thickness of about 0.1 mm to 0.2 mm. Move while holding.

  As shown in FIGS. 11 to 13, the conveyance belt 131 is provided with an attracting force generator 136 described later.

  The attraction force generator 136 applies a voltage of about 0.5 kV to 10 kV to the power supply brush 152 (see FIG. 10) that is in contact with the conveyor belt 131, so that the lower side of each recording head 107K, 107C, 107M, 107Y. In this recording area, an electrostatic attraction force is generated on the conveyor belt 131.

  The power supply brush 152 is connected to a high voltage power source (not shown) that generates a predetermined high voltage.

  The rollers 132, 134, and 135 support the conveyor belt 131 and apply appropriate tension.

  The roller 134 is connected to the paper feed motor 160.

  Further, a support member 139 for the paper pressing roller 140 is attached with the rotation axis of the pinch roller 133 as a rotation center, and the paper pressing roller 140 as a pressing member for pressing the recording paper P against the conveying belt 131 side is supported by this. The member 139 is rotatably attached. The paper pressing roller 140 is urged toward the conveying belt 131 by an urging member (not shown).

  The cleaning roller pair 138 is provided so as to apply pressure across the conveyor belt 131, and can absorb ink in order to remove stains such as ink adhering to the conveyor belt 131, and is durable. In order to prevent deterioration, it is formed of a sponge having a small pore diameter (preferably 10 μm to 30 μm).

  Further, a neutralizing brush 137 that is a neutralizing device for neutralizing the transport belt 131 after being cleaned by the cleaning roller pair 138 is provided.

  A double-sided conveyance path that enables double-sided printing is provided below the conveyance belt 131, and the recording paper P on which single-sided printing has been completed is conveyed to the paper discharge side, and the trailing edge of the recording paper P is discharged. When the paper roller and the spur roller arrive, the paper discharge roller is reversed and guided into the double-sided conveyance path, and the recording paper P is again placed on the conveyance belt 131 through the conveyance roller and the pinch roller to perform double-sided printing. It is.

  Next, the attracting force generator 136 will be described with reference to FIGS. FIG. 11 is a diagram seen from the direction of arrow f in FIG. 10 and is an explanatory diagram showing an electrode pattern and the like of the suction force generator provided on the conveyor belt 131.

  12 is a cross-sectional view taken along the line aa in FIG. 11, and FIG. 13 is a cross-sectional view taken along the line bb in FIG.

  As shown in FIGS. 11 to 13, an adsorption force generator 136 is provided inside the conveyor belt 131.

  The adsorptive power generating device 136 includes an electrode plate 136a and a ground plate 136b made of a resin member kneaded with carbon in a conductive metal or resin.

  As shown in FIG. 11, the attracting force generator 136 is provided on the transport belt 131, and a plurality of independent electrode plates 136a and a plurality of ground plates 136b are alternately arranged in a direction perpendicular to the belt transport direction. It is formed in a comb-like structure arranged so as to extend.

  Widely enlarged terminals 136a ′ and 136b ′ are provided at the ends of the electrode plates 136a and the ground plates 136b, and the terminals 136a ′ and 136b ′ are externally provided at both ends of the conveyor belt 131. It is exposed and becomes a power-supplied part. A conductive power supply brush 152 (see FIG. 10) is provided in contact with each of the terminals 136a ′ and 136b ′ at a predetermined pressure. A positive or negative voltage is applied to the terminal 136a ′ of the electrode plate 136a from a high voltage power source (not shown). The terminal 136b ′ of the ground plate 136b is grounded.

  As shown in FIGS. 12 and 13, the adsorption force generating device 136 constituted of the electrode plate 136 a and the ground plate 136 b in this manner has a base layer 136 c made of a synthetic resin such as polyethylene or polycarbonate as shown in FIGS. And the surface layer 136d are sandwiched and protected to constitute a conveyor belt 131 including an attracting force generator 136.

  When a voltage is applied to the electrode plate 136a, an electrostatic force is generated in the direction of the arrow in FIG. 12, and electric lines of force as shown in FIG. 12 are formed. Then, an attractive force is generated above the conveying belt 131 due to a potential difference between the electrode plate 136a and the ground plate 136b, and a charge (surface) having the same polarity as the voltage applied to the electrode plate 136a is formed on the recording surface of the recording paper P. Potential) occurs.

  Note that the adsorption force of the recording paper P is lowest in a region where there is no conductive electrode member between the electrode plate 136a and the ground plate 136b.

  Next, the suction conveyance operation will be described with reference to FIGS.

  The recording paper P is sandwiched between the transport roller 132 and the pinch roller 133 and placed on the transport belt 131, and is pressed against the transport belt 131 by the paper pressing roller 140. Further, the recording paper P is attracted to the flat portion of the transport belt 131 by the electrostatic attracting force generated by the attracting force generating unit 136.

  The recording paper P is guided to the recording unit by the rotation of the conveying belt 131 while being attracted to the conveying belt 131, and is printed by the recording heads 107K, 107C, 107M, and 107Y, while the paper feeding motor 160 and the roller It is sent in the direction of arrow A by the action of 134.

  When a large amount of ink is ejected onto the recording paper P, the recording paper P may swell and waviness (cockling) may occur. In that case, the recording paper P is attracted to the transport belt 131 side by the electrostatic attraction force of the attracting force generator 136, and the recording paper P is prevented from floating to the recording heads 107K, 107C, 107M, 107Y side, thereby recording. The paper P can be stably recorded without contacting the recording heads 107K, 107C, 107M, and 107Y.

Even when the edge of the recording paper P is wavy or curled due to changes in the environment such as temperature and humidity, the recording paper P is pressed against the conveying belt 131 by the paper pressing roller 140, so Therefore, the recording paper P can be stably adsorbed in the recording unit.
Japanese Patent Application Laid-Open No. 11-151843

  In recent inkjet recording apparatuses, in order to obtain high-definition image quality, the distance between the recording paper P and the recording heads 107K, 107C, 107M, and 107Y is small (for example, 0.5 mm to 1.5 mm) and is kept high while keeping it constant. There is a demand for accurate conveyance.

  In particular, in a one-pass high-speed recording apparatus using a line head, the distance between the recording paper P and the recording heads 107K, 107C, 107M, and 107Y is a factor that directly affects the image quality.

  As the distance between the recording paper P and the recording heads 107K, 107C, 107M, and 107Y is made smaller in this way, the recording paper is wavy or curled when a large amount of ink is ejected onto the recording paper P particularly during double-sided recording. Therefore, it is more desirable than ever to obtain a strong suction force of the recording paper P by the transport belt 131.

  Further, when the use environment changes, the adsorption condition to the belt changes, and the adsorption force may decrease. Therefore, it is desired to always obtain a high adsorption force stably.

  Such a problem may occur not only in the conveyance belt but also in other forms of recording medium carrier such as a rigid drum.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a conveyance device that can stably adsorb and convey a recording medium even when the recording medium is deformed or wavy (cockling) due to a change in use environment or swelling of the recording medium. And providing a recording apparatus having the same.

In order to solve the above problems, the present invention provides a transport apparatus having a transport carrier for transporting a recording medium.
It has a function of controlling the surface resistance value of the recording medium on the conveyance carrier adsorbing surface side of the recording medium to 10 ¹² Ω · cm or less on the upstream side of the conveyance carrier.

Moreover, it has a humidity detection means for detecting the humidity in the transfer device,
Based on the humidity detected by the humidity detection means, the application means supplies moisture uniformly to the entire surface of the recording medium suction surface side, and the application means has a function of being retractable from the recording medium conveyance guide means. Yes.

  Further, the transport carrier is a seamless endless transport belt.

  The electrode has a comb-like electrode structure in which different polarities are alternately arranged.

  The conveyance apparatus includes the image forming apparatus that records an image on the recording medium, and the conveyance carrier conveys the recording medium below the image forming apparatus.

  The image forming apparatus includes an ink jet recording head that ejects ink onto the recording medium.

  According to the present invention, it is possible to suppress the occurrence of flapping or lifting of the recording medium during conveyance due to insufficient adsorption force in any environment, and to stably adsorb and convey the recording medium to form a high-quality image.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
A recording apparatus provided with a recording medium conveying apparatus according to a first embodiment of the present invention will be specifically described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing the overall configuration of the recording apparatus 1 of the present embodiment.

  The recording apparatus 1 includes a paper feeding section 2, a transport section (transport apparatus) 3, a recording section (image forming apparatus) 7, a paper discharge section 4, and a double-side transport section 6.

  The paper feeding unit 2 has a configuration in which a pressure plate 21 on which recording paper P that is a recording medium is stacked and a feeding rotating body 22 that feeds the recording paper P are attached to the base 20.

  The pressure plate 21 can swing around a rotation axis a coupled to the base 20, and is urged toward the feeding rotating body 22 by a pressure plate spring 24. A separation pad 25 made of a material having a large coefficient of friction, such as an artificial skin, is provided at a portion of the pressure plate 21 facing the feeding rotating body 22 to prevent double feeding of the recording paper P.

  Further, the base 20 covers one end of the recording paper P, a release claw 26 for separating the recording paper P one by one, and a release (not shown) for releasing the contact between the pressure plate 21 and the feeding rotating body 22. And a cam.

  Further, a feeding rotating body 90 for manual sheet feeding is provided.

  The feeding rotator 90 feeds the recording paper P placed on the manual feed tray 91 to the transport roller 32 of the transport unit 3 in accordance with a recording command signal from an external computer or the like.

  The transport unit 3 includes a transport belt 31 that sucks and transports the recording paper P.

  As shown in FIGS. 2 to 4, the conveyor belt 31 has a comb-like electrode structure attracting force generator 36 composed of an electrode plate 36a and a ground plate 36b, a base layer 36c, and a surface layer 36d. It is composed of

  The conveyor belt 31 is driven by a driving roller 34 and is stretched between the driving roller 34, a conveyor roller 32 that is a driven roller, and a pressure roller 35.

  The conveyor belt 31 is a seamless endless belt made of a synthetic resin such as polyethylene or polycarbonate having a thickness of about 0.1 mm to 0.2 mm, and moves while adsorbing and holding the recording paper P.

  The conveyance belt 31 is provided with an adsorption force generator 36. The attracting force generator 36 generates an electrostatic attracting force on the transport belt 31 by applying a voltage of about 0.5 kV to 10 kV to the power supply brush 52 in contact with the transport belt 31.

  The power supply brush 52 is connected to a high voltage power source (not shown) that generates a predetermined high voltage.

  As shown in FIGS. 1, 6, and 7, the conveying roller 32 and the driving roller 34 are rotatably attached to the platen 30.

  The pressure roller 35 is rotatably attached to the other end of an arm 50 that is swingably attached to the platen 30. When the arm 50 is pressed by a spring 51, tension (2 0.0 kgf: 19.6 N).

  The platen 30 is positioned below the conveyor belt 31 and serves to regulate the downward displacement of the conveyor belt 31.

  A pinch roller 33 driven by the conveyance belt 31 is provided in contact with the conveyance roller 32 at a position facing it.

  The pinch roller 33 is pressed against the conveyance belt 31 by a spring (not shown), and guides the recording paper P to the recording unit 7 by rotating together with the conveyance belt 31.

  Further, the pinch roller 33 is electrically connected to a main body frame (not shown), and removes charges accumulated on the surface layer 36d of the conveyor belt 31.

  Further, an upper guide 27 and a lower guide 28 for guiding the recording paper P are provided at the entrance of the transport unit 3 to which the recording paper P is transported.

  The upper guide 27 is provided with a PE sensor lever 23 for detecting the leading edge and the trailing edge of the recording paper P.

  A pair of cleaning rollers 38 is provided so as to apply pressure across the conveyor belt 31.

  The cleaning roller pair 38 can absorb ink in order to remove dirt such as ink adhering to the conveyor belt 31 and has a small pore diameter (10 μm to 30 μm to prevent deterioration in durability). (Preferably) formed of open-cell sponge.

  In addition, a neutralizing brush 37 is provided as a neutralizing unit for neutralizing the transport belt 31 after being cleaned by the cleaning roller pair 38.

  A recording unit 7 that forms an image based on image information is provided on the downstream side of the conveyance roller 32 of the conveyance unit 3 in the recording sheet conveyance direction.

  The recording unit 7 includes an inkjet recording head that is a line type image forming apparatus in which a plurality of nozzles are arranged in a direction orthogonal to the conveyance direction of the recording paper P, and the black recording is performed from the upstream side in the conveyance direction of the recording paper P. A head 7K, a cyan recording head 7C, a magenta recording head 7M, and a yellow recording head 7Y are arranged at predetermined intervals in this order, and each recording head 7K, 7C, 7M, 7Y is attached to a head holder 7A. ing.

  Each of the recording heads 7K, 7C, 7M, and 7Y heats the ink by a built-in heater or the like to cause the ink to boil, and ejects ink from a nozzle (not shown) due to pressure changes caused by the growth or contraction of bubbles due to the film boiling. It is something to be made.

  A head holder 7A to which the recording heads 7K, 7C, 7M, and 7Y are attached is fixed at one end to a shaft 71 so as to be swingable, and a protrusion 7B formed at the other end engages with a rail 72. In addition, the distance between the nozzle surface and the recording paper P (inter-paper distance) is defined.

  The paper discharge unit 4 includes a paper discharge roller 41 and a spur 42 and discharges the recording paper P on which an image has been formed by the recording unit 7 to a paper discharge tray 43.

  The paper discharge roller 41 is driven by the rotational force of the drive roller 34 being transmitted via a transmission means (not shown). Since the spur 42 rolls on the recording surface after recording, the contact area with the recording paper P is small, and the recording image of the recording paper P is not disturbed as much as possible even if it contacts the recording surface after recording. ing.

  The double-sided conveyance unit 6 has a plurality of feed rollers in the double-sided conveyance path for performing double-sided printing, and reverses when the recording paper P conveyed to the paper discharge side is introduced after printing on one side is completed. Thus, the recording paper P is placed on the conveying belt 31 again between the conveying roller 32 and the pinch roller 33.

  A recording method by the ink jet recording apparatus 1 having such a configuration will be briefly described.

  First, in a standby state before recording, the release cam of the paper feeding unit 2 pushes the pressure plate 21 down to a predetermined position, and the contact between the pressure plate 21 and the feeding rotating body 22 is released.

  In this state, when the conveying roller 32 is operated and the driving force is transmitted to the feed rotating body 22 and the release cam by a gear or the like, the release cam is separated from the pressure plate 21 and the pressure plate 21 is lifted, and the feed rotating body. 22 and the recording paper P on the pressure plate 21 abut. Therefore, the recording paper P is picked up with the rotation of the feeding rotating body 22, separated one by one by the separation claw 26, and fed to the transport unit 3. The feeding rotator 22 rotates until the recording paper P is fed into the transport unit 3, and again enters a standby state in which the contact between the recording paper P and the feeding rotator 22 is released. Is cut off.

  The recording paper P sent to the transport unit 3 in this manner is guided by the upper guide 27 and the lower guide 28 and sent between the transport roller 32 and the pinch roller 33.

  At this time, the PE sensor lever 23 detects the leading edge of the conveyed recording paper P, and the recording position of the recording paper P is obtained based on the detected result.

  Further, the recording paper P is conveyed by the conveyance belt 31 rotating via the conveyance roller 32 by a paper feed motor.

  When the recording paper P is conveyed to the recording unit 7, the recording heads 7K, 7C, 7M, and 7Y discharge ink of each color.

  While the recording paper P is conveyed at an appropriate timing, it receives ink of each color ejected from the recording heads 7K, 7C, 7M, and 7Y, and thereby a desired image (including characters and patterns) is provided on one side of the recording paper P. ) Is formed.

  When recording on one side of the recording paper P is completed and conveyed to the paper discharge side, and the trailing end of the recording paper P arrives between the paper discharge roller 41 and the spur roller 42, the paper discharge roller 41 reverses and the recording paper P is conveyed in the reverse direction and introduced into the double-sided conveyance unit 6.

  The recording paper P is transported by a plurality of feed rollers in the double-side transport path, and is placed on the transport belt 31 again through the space between the transport roller 32 and the pinch roller 33 in an inverted state.

  Then, the recording heads 7K, 7C, 7M, and 7Y again eject ink of each color, and a desired image (including characters and patterns) is formed on the back surface of the recording paper P.

  When the recording on both sides is completed in this manner, the paper discharge roller 41 is rotated forward by being driven by the drive roller 34, and the recording paper P passes between the paper discharge roller 41 and the spur 42 and is discharged to the paper discharge tray 43.

  Next, the structure of the conveyance part 3 which is the main feature of this invention is demonstrated in more detail mainly with reference to FIGS. FIG. 6 is a perspective view showing the overall structure of the transport unit 3, and FIG. 7 is a schematic sectional view thereof.

  First, the platen 30 that is the frame of the transport unit 3 will be described. As shown in FIGS. 6 to 8, the platen 30 has a nozzle surface in a nozzle row direction (a direction perpendicular to the conveying direction of the conveying belt 31) at a position facing each recording head 7 </ b> K, 7 </ b> C, 7 </ b> M, 7 </ b> Y. A convex portion 30a is provided in parallel with the (face surface).

  The front end surface 30b of each convex portion 30a, that is, the surface facing each recording head 7K, 7C, 7M, 7Y has a predetermined width in the transport direction of the transport belt 31, and is located in the same plane. is doing. The convex portion 30a is made of a material having conductivity in order to obtain a sufficient suction force, and a low friction layer such as a Teflon (registered trademark) film or a high molecular weight polyethylene film is formed on the leading end surface 30b on which the conveying belt 31 slides. 30c (thickness: 100 μm, friction coefficient 0.2) is formed on the entire surface, reducing friction during conveyance of the conveyor belt 31 and stabilizing rotational load during rotation, ensuring high conveyance accuracy. Yes.

On the other hand, as shown in FIGS. 3, 4, and 8, the conveyor belt 31 is added with an ionic conductor (electrolyte: a substance through which ions serve as carriers) on the surface layer (surface that adsorbs the recording paper P). A laminated structure including a medium resistance layer (surface layer) 36d and an insulating layer (base layer) 36c having the above-described configuration, and an electrostatic force is generated by applying an electric charge to the electrode plate 36a located in the intermediate layer, thereby producing a recording medium. The surface layer is controlled to have a resistance value of about 10 ¹¹ Ω · cm.

  The intermediate layer is also provided with a ground plate 36b that is grounded.

In general, an object is classified into an insulator, a semiconductor, and a conductor according to a surface resistance value. Paper that is a recording medium (recording paper P) belongs to an insulator, and generally has a resistance value of about 10 ¹¹ to 10 ¹² Ω · cm. is there.

When the surface resistance value of the paper as the recording medium and the resistance value of the surface layer 36d of the conveying belt 31 are substantially the same (for example, 10 ¹¹ Ω · cm), the adsorption force is sufficiently exerted.

  However, if the resistance value of the recording paper surface layer is large, it is difficult for current to flow, and the attractive force is reduced.

  On the other hand, when moisture is condensed on the surface layer of the recording paper, current flows through the condensed layer and the adsorption force is reduced.

  In a state where moisture is not exposed on the surface layer of the recording paper (in the wet state, but the moisture does not adhere to the hand when touched by hand), the surface resistance value of the recording paper is reduced and the adsorption force is not reduced.

  The result obtained by the inventor's experiment is a graph showing the relationship between the resistance value of the recording paper surface layer and the humidity in FIG.

  The vertical axis represents the surface layer resistance value of the recording paper, and the horizontal axis represents the environmental humidity where the recording paper is placed.

The moisture content in the recording paper at normal humidity (50 to 60%) is about 5 to 7%, the resistance is about 10 ¹¹ to 10 ¹² Ω · cm, and the resistance is about 3% at low humidity (20%). The resistance value was about 10 ⁹ Ω · cm at about 10 ¹⁴ Ω · cm, about 10% at high humidity.

  As indicated by the broken line, the resistance value of the surface layer changes depending on the humidity, and the resistance value increases particularly at low temperatures, and the difference in the resistance value of the surface layer 36d of the conveyor belt 31 is large. I couldn't get power.

  This is because the moisture content in the recording paper changes depending on the environment as described above.

Accordingly, the present inventor has determined the humidity of the paper feeding unit 2 including the pressure plate 21 on which the recording paper P, which is a recording medium in the recording apparatus 1, and the feeding rotating body 22 for feeding the recording paper P, as a humidity detector. (Detection sensor not shown) When the detection sensor detects a change in humidity, the control unit (not shown) responds to the change in humidity by a small amount (recording on the back side of the recording belt). The surface layer of the recording paper has a resistance value of 10 ¹¹ to 10 at the same level as normal humidity (50 to 60%). By setting it to about ¹² Ω · cm, it was possible to reliably adsorb even under low humidity conditions (see the solid line in FIG. 9).

  With reference to FIG. 5, the schematic configuration of the moisture applying means on the back side of the recording paper will be described.

  The moisture applying means is located below the recording paper transport guide rollers 10 and 11 disposed on the upstream side of the pinch roller 33.

  The purpose of the conveyance guide roller is not only the conveyance of the recording sheet but also a conveyance guide roller that normally guides the recording sheet. Therefore, the driven guide roller is rotated in contact with the drive guide roller with its own light weight.

  The drive guide roller 11 is an elastic roller in which the surface of a foam of a small cell having a small pore diameter (preferably 10 μm to 30 μm) is formed of a film in order to prevent deterioration in durability.

  The application roller 12 located immediately below is configured to be swingable, and is usually located in the moisture supply tray 13 located away from the drive roller 11.

  When the humidity detector detects a change in humidity of the paper feeding unit 2 on which the recording paper P, which is a recording medium in the recording apparatus 1, is loaded, the information is transmitted to the control unit, and a timer is provided for the distance from the feed rotating body 22 to the drive guide roller 11. The application roller 12 is raised at a delay after the application roller 12 is raised to supply a minute amount of uniform moisture 14 to the surface of the driving roller, and this is applied to the back side of the recording paper (conveying belt suction side). .

  As long as the application member has good water absorption, the material may be paper, cloth, rubber or the like.

  Although the embodiment has been described with a roller, the effect is the same with a plate-like object instead of the roller.

  By oscillating the application roller 12 according to humidity, the surface resistance value of the recording paper can always be kept constant without applying extra moisture to the back side of the recording paper except when the humidity is low.

  Also, for example, when printing on both sides under low humidity conditions, the surface resistance of the recording paper is lower than the resistance value at normal low humidity (normal humidity), so there is no need for coating and stable adsorption power is obtained. It is done.

  In the present embodiment, it is not necessary to adopt a device for keeping the humidity in the device mounted on the conventional large device constant or a configuration for shielding the conveyance path from the outside air, and from a general business machine to a large printing device. Can be achieved with a simple configuration.

[Other Embodiments]
In the above-described embodiment, the case of an ink jet recording apparatus for color recording using a plurality of recording heads 7K, 7C, 7M, and 7Y that records with different color inks has been described as an example. For example, an ink jet recording apparatus using one recording head, or an ink jet recording apparatus for gradation recording using a plurality of recording heads that record with a plurality of inks having the same color and different densities, is not limited. The present invention can be similarly applied regardless of the number of heads, and can achieve the same effects as described above.

  As the image forming apparatus (recording head), a cartridge type in which the recording head and the ink tank are integrated, or a structure in which the recording head and the ink tank are formed separately and connected by an ink supply tube, etc. The present invention can be similarly applied regardless of the configuration of the recording head and the ink tank, and the same effect as described above can be achieved.

  Furthermore, the present invention can be effectively applied to a so-called serial type recording apparatus that performs recording while moving the recording head in a direction orthogonal to the conveyance direction of the recording medium.

  Alternatively, even if the recording head is a full-line type recording apparatus having a length corresponding to the maximum width of the recordable recording medium, a configuration that satisfies the length by a combination of a plurality of recording heads, Any of the structures as one formed recording head may be used.

  In addition, even in the serial type configuration described above, the recording head fixed to the main body of the recording apparatus 1 or attached to the main body of the recording apparatus 1 can be electrically connected to the main body of the recording apparatus 1 or from the main body of the recording apparatus 1. The present invention is also effective in the case of using a replaceable chip type recording head that can supply ink, or a cartridge type recording head in which an ink tank is integrally provided in the recording head itself.

  In addition, when the present invention is applied to an ink jet recording apparatus, for example, it can be applied to an apparatus using an image forming apparatus using an electromechanical transducer such as a piezo element. This is an excellent effect in an ink jet recording apparatus using an image forming apparatus of a discharge type.

  This is because such a system can achieve higher recording density and higher definition.

  Further, as the form of the above-described ink jet recording apparatus, in addition to those used as image output terminal devices of information processing devices such as computers, ink jet input / output apparatuses and readers that can mount a scanner other than the recording head on the carriage Or a facsimile machine having a transmission / reception function.

  The transport carrier for transporting the recording medium does not necessarily have to have a belt shape as in the above-described embodiment, and may have a rigid drum shape.

1 is a cross-sectional view illustrating an overall configuration of a recording apparatus according to a first embodiment of the present invention. FIG. 2 is a plan view of a conveyance unit of the recording apparatus in FIG. 1. It is the sectional view on the aa line of FIG. It is the bb sectional view taken on the line of FIG. It is a schematic block diagram of a moisture application means. FIG. 2 is a perspective view illustrating an overall configuration of a conveyance unit of the recording apparatus in FIG. 1. It is a schematic sectional drawing of the conveyance part shown in FIG. It is a principal part enlarged view of FIG. It is a graph which shows the relationship between the resistance value of a recording paper surface layer, and humidity. It is sectional drawing which shows the structure of the conveyance part of the conventional recording device. It is a top view of the conveyance part of the recording device of FIG. It is the sectional view on the aa line of FIG. It is the bb sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording device 2 Paper feed part 3 Conveyance part (conveyance apparatus)
4 Paper discharge unit 6 Double-sided conveyance unit 7 Recording unit (image forming apparatus)
7A Head holder 7B Protrusion 7K, 7C, 7M, 7Y Recording head 10 Driven guide roller 11 Drive guide roller 12 Application roller 13 Moisture supply tray 14 Moisture 20 Base 21 Pressure plate 22 Feed rotating body 23 PE sensor lever 24 Pressure plate spring 25 Separation Pad 26 Separation claw 27 Upper guide 28 Lower guide 30 Platen 30a Protruding portion 30b Tip surface 30c Low friction layer 31 Conveying belt 32 Conveying roller 33 Pinch roller 34 Driving roller 35 Pressure roller 36 Adsorption force generating device 36a Electrode plate 36b Ground plate 36c Base Layer 36d Surface layer 37 Static elimination brush 38 Cleaning roller pair 41 Paper discharge roller 42 Spur 43 Paper discharge tray 50 Arm 51 Spring 52 Power supply brush 54 Controller 55 Temperature detector (detection sensor)
71 Shaft 72 Rail 90 Feeding Rotator 91 Manual Tray 103 Conveying Sections 107K, 107C, 107M, 107Y Recording Head 131 Conveying Belt 132 Conveying Roller 133 Pinch Roller 134 Driving Roller 135 Pressure Roller 136 Adsorption Force Generating Device 136a Electrode Plate 136b Ground Plate 136c Base layer 136d Surface layer 136a ', 136b' Terminal 137 Static elimination brush 138 Cleaning roller pair 139 Support member 140 Paper pressing roller 152 Power supply brush 160 Paper feed motor a Rotating shaft P Recording paper

Claims (6)

In a transport apparatus having a transport carrier for transporting a recording medium,
A transport apparatus having a function of controlling a surface resistance value of the recording medium on the transport carrier adsorbing surface side to 10 ¹² Ω · cm or less upstream of the transport carrier. Having humidity detecting means for detecting the humidity in the conveying device;
The moisture is uniformly supplied to the entire surface of the recording medium adsorbing surface by the application unit based on the humidity detected by the humidity detection unit, and the application unit can be retracted from the recording medium conveyance guide unit. Item 2. The transfer device according to Item 1.   The transport apparatus according to claim 1, wherein the transport carrier is an endless transport belt having no joints.   The conveying device according to claim 1, wherein the electrode has a comb-like electrode structure in which different polarities are alternately arranged.   5. The conveyance device according to claim 1, and an image forming apparatus that records an image on the recording medium, wherein the conveyance carrier conveys the recording medium below the image forming apparatus. A recording apparatus.   The recording apparatus according to claim 5, wherein the image forming apparatus includes an ink jet recording head that ejects ink onto the recording medium.

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